Bullous diseases and blistering1) Which pair is incorrect?

A. Lichen planus : linear C3 Correct Choice

B. Bullous pemphigoid : linear C3

C. IgA pemphigus: intercellular IgA

D. Dermatitis herpetiformis : granular IgA

E. Systemic lupus erythematosus : linear IgG

The colloid bodies in lichen planus can trap IgM and C3; this can be seen on DIF as “globs.” There is no linear pattern

2) In penicillamine-induced pemphigus, the split is most often:

A. Subcorneal Correct Choice

B. Subepidermal

C. Suprabasal

D. Intraepidermal and subepidermal

E. Intraspinous

Penicillamine is the most common cause of drug-induced pemphigus, and the split is more often subcorneal (pemphigus foliaceus-like) than suprabasal (pemphigus vulgaris-like).

3) Herpes gestationis is exacerbated by:

A. Postpartum state

B. Oral contraceptives

C. All of these answers are correctCorrect Choice

D. Third trimester

E. Menstruation

Herpes gestationis has also been associated with choriocarcinoma in several case reports

4) Common drugs causing SJS/TEN include all except:

A. Carbamazepime

1

B. Allopurinol

C. Sulfonamides

D. Oxicam

E. Colchicine Correct Choice

NSAIDs, anticonvulsants, allopurinol, and sulfa drugs are common inciting agents of SJS/TEN

5) This is derived from Myroxylon pereirae:

A. Aniline dyes

B. Thimerosol

C. Thiuram

D. Colophony

E. Balsam of Peru Correct Choice

Balsam of Peru is derived from the Myroxylon pereriae tree. Thimerosal is a questionable cause of allergic contact dermatitis; it is found in vaccines and contact lens solutions

6) In Brunsting-Perry pemphigoid, the recrurrent crops of blisters are most likely to appear on:

A. Head and neckCorrect Choice

B. Umbilicus

C. Genitals

D. Buttocks

E. Palms and soles

Brunsting-Perry pemphigoid is a variant of cicatricial pemphigoid in which there are no mucosal lesions. The most common site of blisters is the head and neck, resulting in scarring alopecia. The antigens in cicatricial pemphigoid include BPAg2 and epiligrin

7) The croton plant is irritating secondary to:

A. Thiocyanate

B. Capsaicin

C. Protoanemonin

2

D. Calcium oxalate

E. Phorbol esters Correct Choice

Irritant contact dermatitis secondary to the croton plant is due to phorbol esters. Calcium oxalate is also an irritant; it is found in the “dumb caine” plant, a common house plant (Dieffenbachia) as well as in daffodils. Thiocyanates are irritants found in garlic. Protoanemonins are irritants found in buttercups

8) Circulating autoantibodies to type XVII collagen are most characteristic of which disease?

A. Epidermolysis bullosa accquisita

B. Paraneoplastic pemphigus

C. Pemphigus vulgaris

D. Pemphigus foliacious

E. Herpes gestationisCorrect Choice

Type XVII collagen or BPAG2 is a transmembrane protein found in the hemidesmosome. Autoantibodies to type XVII collagen are important in the pathogenesis of cicatricial pemphigoid, bullous pemphigoid, and herpes gestationis

9) What is the enzyme defect in Gunther's disease?

A. Protoporphyrinogen oxidase

B. Uroporphyrinogen synthetase IIICorrect Choice

C. Uroporphyrinogen decarboxylase

D. Ferrochetalase

E. Porphobilinogen deaminase

Gunther's disease (also known as congenital erythropoietic porphyhria) is caused by a defect in uroporphyrinogen synthetase II, the enzyme which responsible for the conversion of hydroxymethylbilane to uroporphyriogen III. Patients present with red teeth and immediate photosensitivy during infancy. There is severe photophobia and late skin manifestations include mutilating scarswith scarring alopecia, and sclerodermoid changes

10) Which form of epidermolysis bullosa presents with generalized bullae, absent nails, dysplastic teeth (due to enamel defects), nonhealing granulation tissue periorally, and is often fatal by age 3-4?

A. Hyperplastic cockayne-touraine

B. Albapapuloid Pasini variant

3

C. HerlitzCorrect Choice

D. Weber-cockayne

E. Non-Herlitz

Junctional EB is an autosomal recessive disorder with a defect in the lamina lujcida; uncein is absent in all forms. The Herlitz variant is due to mutations in laminin 5 and clinically presents as generalized bullae (which are non-scarring), nonhealing granulation tissue periorally, absent nails, dysplastic teeth and enamel defects, anemia, growth retardation and is often fatal by age 3-4 due to low protein, anemia and infection. The non-Herlitz variant of Junctional EB presents with bullae especially on the extremities which heal with atrophic scarring; pts improve with age and typically have a normal life span. Weber-cockayne is a type of EB simplex and presents with palmoplantar bullae and hyperhidrosis. Hyperplastic cockayne-touraine is a form of dominant dystrophic EB which presents with bullae localized to extremities. Albapapuloid Pasini variant of dystropohic EB presents with widespread bullae, atrophy, hypopigmented scar-like white papules on trunk, no miliaar or scarring, and mild oral involvement

11) Pemphigus erythematosus:

A. Is often in a malar/seborrheic distribution Correct Choice

B. Is also called Hallopeau syndrome

C. All of these answers are correct

D. Does not have linear IgG and C3 at the basement membrane zone

E. May be an abortive form of subcorneal pustulosis

Pemphigus erythematosus, or Senear Usher syndrome, presents like pemphigus foliaceus and lupus erythematosus with very superficial erosions and erythematous/hyperkeratotic facial/chest lesions. DIF reveals intercellular IgG and linear IgG at the dermoepidermal junction

12) Patients with this disorder may develop exaggerated reactions to insect bites:

A. Bullous pemphigoid

B. Atopic dermatitis

C. Chronic lymphocytic leukemia Correct Choice

D. Incontinentia pigmenti

E. Lupus erythematosus

Patients with chronic lymphocytic leukemia may develop exaggerated reactions to insect bites, including bullous reactions

13) In staphylococcal scalded skin syndrome, the exfoliative toxin cleaves:

4

A. Desmocollin 3

B. Desmoglein 3

C. Desmoglein 1Correct Choice

D. Desmocollin 1

E. BpAg2

Staphylococcal scalded skin syndrome is caused by Staphylococci group 2, phage typ 71, which produces an exofliative toxin that cleaves desmoglein 1. Clinically, this results in a subcorneal separation of keratinocytes, leading to skin tenderness, erythema, and superficial desquamatioin of skin

14) Epidermolysis bullosa simplex is caused by mutations in:

A. Keratins 1&10

B. Keratins 5&14Correct Choice

C. Keratins K2e&10

D. Keratins 1&9

E. Keratins 6a &16

EB Simplex is caused by mutations in keratins 5 &14. Mutations in Keratins 1&10 are associated with epidermolytic hyperkeratosis ande Unna-thost. Mutations in keratins 1&9 are associated with epidermolytic palmoplantar keratoderma. Mutations in Keratins 6a and 16 are associated with Pachyonychia congenital. Mutations in K2e and 10 are associated with Icthyosis bullosa of Siemens

15) The agent most likely to cause pseudoporphyria is:

A. Ace-inhibitors

B. Vancomycin

C. Penicillin

D. Beta-blockers

E. NSAID'sCorrect Choice

NSAIDS,especially naprosyn, are the most common group of drugs implicated in pseudoporphyria. Other common offenders include lasix, tetracycline, accutane, amiodarone and tanning beds

16) Which pair is incorrect?

A. Type XVII collagen: 180 kDa

5

B. Type VII collagen : 290 kDa

C. Desmoplakin I : 250 kDa

D. Desmoglein 1 : 160 kDa

E. Envoplakin : 190 kDa Correct Choice

Envoplakin is 210 kDa. Periplakin is 190 kDa

17) Each of the following is true about anti-p200 pemphigoid except:

A. Responsive to dapsone

B. Subepidermal bullae

C. 200-kd antigen

D. features of linear IgA disease

E. mucosal involvementCorrect Choice

Anti-p200 pemphigoid is an autoimmune blistering disorder. These autoantibodies bind to a 200-kD antigen found at the lamina lucida-lamina densa interface, thereby causing a subepidermal bullae. Clinical features of this disease are similar to bullous pemphigoid, dermatitis herpetiformis and linear IgA disease. In the case reported by Egan, et.al., the patient responded well to steroids and dapsone and did not have mucosal lesions

18) Common cause(s) of drug-induced pemphigus foliaceus:

A. Methotrexate

B. Dilantin

C. Penicillamine

D. Captopril

E. Captopril and penicillamine Correct Choice

Penicillamine and captopril are common causes of drug-induced pemphigus

19) Chloracne may be secondary to exposure to:

A. Dioxin Correct Choice

B. Methylchloroisothiazolinone

C. Chloroacetophenone

6

D. Hydrocarbons

E. Hydrochloric acid

Chlorinated compounds can cause irritant dermatitis and sometimes chloracne. Chlorinated compounds include chloronaphthalene, chlorodiphenyl, dichlorobenzonitrile, tetrachloroazooxybenzene; dioxin (exposure in the Vietnam war); and cutting oils. Chloroacetophenone is an irritant in tear gas

20) Which association is incorrect?

A. Porphyria cutanea tarda : hemochromatosis

B. Epidermolysis bullosa acquisita : inflammatory bowel disease

C. Paraneoplastic pemphigus : Castleman’s

D. Herpes gestationis : menopause Correct Choice

E. Dermatitis herpetiformis : small bowel lymphoma

NEEDS EXPLANATIONS

21) Which autoantibodies would most likely be found in an individual with these eye findings without any cutaneous involvement?

A. Alpha 6 beta 4 integrinCorrect Choice

B. Laminin 5

C. Bullous pemphigoid antigen 2

D. Desmocollin

E. Bullous pemphigoid antigen 1

Cicatricial pemphigoid is a rare, heterogeneous group of blistering diseases with predilection for mucous membranes. It may involve the eyes, oral mucosa, genital/anal mucosa, and skin. The ocular form of cicatricial pemphigoid without cutaneous findings is usually associated with circulating autoantibodes to alpha 6 beta 4 integrin

22) Which of the following is the most common photoallergen?

A. glyceryl thioglycolate

B. Dihydroxyacetone

C. octyl dimethyl PABA

D. Benzophenone

7

E. OxybenzoneCorrect Choice

Oxybenzone is a UVA sunscreen and is the most common photoallergen. Octyle dimethyl PABA (Padimate O) and benzophenone are also sunscreen agents, and both can also cause contact dermatitis. Dihydroxyacetone is a sunless-tanning agent and glyceryl thioglycolate is found in permanent wave solutions

23) Oriental" tiger balm cross-reacts with:

A. Lanolin

B. Neomycin

C. Balsam of PeruCorrect Choice

D. Rosin

E. Ylang-Ylang oil

"Oriental" tiger balm is a popular Chinese proprietary ointment used to relieve aches and pains. Patients who develop allergic contact dermatitis to this agent have also been shown to have cross-reactions with balsam of Peru. A similar substance known as "Bavarian" tiger balm has been reported to cross react with rosin

24) Patients with Duhring's disease are most likely to have:

A. Antibodies to BPAg2

B. Mutations in transglutaminase I

C. Antibodies to transglutaminase 3Correct Choice

D. Mutations in laminin 5

E. Mutations in plectin

Duhring's disease is also known as dermatitis herpetiformis. Antibodies are found to transglutaminase 3, and the direct immunofluorescent studies show granular IgA and C3 in the dermal papillae. Mutations in plectin are found in EBS with muscular dystrophy. Mutations in laminin 5 are found in patients with JEB,Herlitz type. Mutations in transglutaminase I are found in pateints with lamellar ichthyosis and non bullous congenital ichthyosiform erythroderma

25) Cleavage of this adhesion molecule is seen in Staphylococcal Scalded Skin Syndrome:

A. Desmoglein 1 Correct Choice

B. Desmoplakin 2

C. Desmoplakin 1

8

D. Desmoglein 3

E. Desmoplakin 1 and desmoplakin 2

Desmoglein 1 is cleaved by exfoliative toxin in Staphylococcal scalded skin syndrome

26) Gallstones are associated with:

A. Harderoporphyria

B. Coproporphyria

C. Variegate porphyria

D. Hepatoerythropoietic porphyria

E. Erythropoietic protoporphyria Correct Choice

Gallstones and liver failure can complicate erythropoietic protoporphyria

27) What is the antigen associated with dermatitis herpetiformis?

A. Tissue transglutaminaseCorrect Choice

B. Desmocollin

C. Epilegrin

D. Desmoglein 3

E. Periplakin

Dermatitis herpetiformis is an autoimmune blistering disease associated with intense pruritus. Classically, it involves the extensor aspects of the body. Antibodies to tissue transglutaminase (anti-endomesial, anti-gliadin, anti-reticulin) can be found. It is associated with celiac sprue. 50% have thyroid disease

28) Which of the following chemicals is the most common cause of shoe contact dermatitis?

A. Carba mix

B. Mixed dialkyl thioureas

C. Thiuram mix

D. 2-MercaptobenzothiazoleCorrect Choice

E. Formaldehyde

9

2-Mercaptobenzothiazole is found in the soles of shoes, and is the #1 cause of shoe contact dermatitis. It is also found in rubber accelerators, adhesives/tape, coolants, rubber, flea/tick powder, and support hose. Thiuram mix, carba mix, and mixed dialkyl thioureas are also rubber sensitizers. Thiuram is the second most frequent source of shoe contact dermatitis. Formaldehyde is a preservative and not found in shoes

29) Which of the following is true of a phototoxic reaction?

A. Develops after repeated exposures

B. Results in direct tissue injuryCorrect Choice

C. Requires prior sensitization of photoallergen in susceptible individuals

D. Photoallergen must bind to carrier protein

E. Produces an eczematous reaction

Phototoxic reactions result in direct tissue injury when the phototoxic agent interacts with light energy to form reactive oxygen species. It is characterized by an eruption similar to a sunburn

30) This is found in both desmosomes and adherens junctions:

A. Lamin

B. Desmoglein 1

C. Plakoglobin Correct Choice

D. Desmoglein 3

E. Alpha-catenin

Plakoglobin is a plaque protein of the armadillo family that is found in desmosomes; it can also substitute for beta-catenin in adherens junctions. Plakoglobin co-precipitates with desmogleins. It is 85 kDa

31) Epidermolysis bullosa simplex with muscular dystrophy is associated with a mutation in:

A. collagen VII

B. PlectinCorrect Choice

C. alpha 6 beta integrin

D. Laminin 5

E. uncein

EB Simplex is an autosomal dominant disorder caused by mutations in keratins 5 &14, leading to intraepidermal bullae. A subtype of EBS patients have muscular dystrophy due to a defect in plectin.

10

Laminin 5 mutations are associated with junctional EB. Collagen VII mutations are associated with dystrophic EB. Uncein is a protein in the lamina lucida which is found to be absent in junctional EB. Mutations in alpha6-beta4 integrins are associated with JEB with pyloric atresia

32) Perioral exuberant granulation tissue is sometimes seen in:

A. Duhring’s

B. Weber-Cockayne

C. Cicatricial pemphigoid

D. Herlitz Correct Choice

E. Weber-Cockayne

The Herlitz form of junctional EB sometimes presents with excessive granulation tissue periorally, in the axillary/neck area

33) Irritation of the hand produced by capsaicin can be relieved by application of

A. Sodium chloride

B. Alkali

C. Acetic acid 5% Correct Choice

D. Water

E. Talcum powder

Burning secondary to capsaicin can be relieved by vinegar (acetic acid 5%) as the capsaicin is soluble in vinegar (but not water).

34) Which of the following can be responsible for contact dermatitis to K-Y Jelly?

A. Alpha tocopherol

B. Budesonide

C. Lanolin alcohol

D. Triclosan

E. Propylene glycolCorrect Choice

Propylene glycol is a widely used solvent and humectant found in a variety of products such as cosmetics, lotions, corticosteroids, antiperspirants, and K-Y jelly. Lanolin is an emollient which comes from wool wax and is found in adhesives, cosmetics, and topical emollients such as Aquaphor. Budesonide is a steroid, alpha tocopherol is topical Vitamin E, and Triclosan is a topical antibiotic

11

35) What is the most common allergen causing allergic contact dermatitis?

A. Quaternium-15

B. Bacitracin

C. Formaldehyde

D. Nickel Correct Choice

E. Neomycin

Nickel is the most common contact allergen, found in “costume” jewelry, alloys, pigments orthopedic appliances, scissors, razors and many other metal coated objects. Bacitracin and neomycin are commonly used topical antibiotic agents that many are allergic to. Neomycin is the most common topical antibiotic allergen found in testing. Quaternium-15 is a formaldehyde-releasing preservative found in many topical products. It can cross react with formaldehyde, but not all patients will react to formaldehyde on testing. While it is a common allergen, it is not the most common cause of ACD

36) The primary autoantigen in pemphigoid gestationis is

A. Plakoglobin

B. Desmoplakin

C. BPAG1

D. Anchoring fibrils

E. BPAG2Correct Choice

Herpes gestationsis is an autoimmune blistering disorder of pregnancy. It is characterized by urticarial plaques and tense bullae. Antibodies to BPAG2 are thought to form as a result of an aberreant response to MHC antigens on the placenta. The maternal health is generally not affected, but infants are more commonly born premature. Remission is common following delivery, but it may recur with OCP's, menstruation, and subsequent pregnancies

37) Which of the following proteins is typically NOT found to be antigenic in paraneoplastic pemphigus?

A. Periplakin

B. BPAg2Correct Choice

C. Envoplakin

D. BPAg1

E. Desmoplakin

12

BPAg2, a 180kDa protein, is typically not found to be antigenic in paraneoplastic pemphigus. The proteins typically involved are: desmplakin 1 (250kDa) BPAg1 (230 kDa) Envoplakin (210kDa) Desmoplakin 2(210kDa) Periplakin (190 kDa) Unknown protein (170 kDa) Desmogleins 1& 3 (160 and 130 kDa

38) The epidermolysis bullosa acquisita antigen is:

A. Located in the lamina lucida

B. A desmosomal protein

C. A transmembrane protein

D. An intracellular protein

E. An anchoring fibrilCorrect Choice

Epidermolysis bullosa acquisita is a rare autoimmune disorder with an estimated incidence of 0.25 per million. In the classic form, it is characterized by non-inflammatory bulla with a prediliction for traumatized sites. The autoantigen is type VII collagen, which is an anchoring fibril located in the sublamina densa. Following salt split skin, the type VII collagen can be localized at the base

39) The most common malignancy associated with paraneoplastic pemphigus is:

A. Chronic lymphocytic leukemia

B. Acute myelocytic leukemia

C. Non-Hodgkin’s lymphoma Correct Choice

D. Multiple myeloma

E. Hodgkin’s lymphoma

Paraneoplastic pemphigus is associated with various benign as well as malignant internal tumors, with the most common being non-Hodgkin’s lymphoma

40) What is the antigen in penicillamine induced pemphigus?

A. Desmoglein 1

B. Plakoglobin

C. DesmocollinCorrect Choice

D. Desmoglein 3

13

E. Tissue transglutaminase

Penicillamine is chelating agent that is used in the treatment of Wilson's disease and rheumatoid arthritis. It has implicated in many drug reactions including drug induced pemphigus and elastosis perforans serpiginosa. In penicillamine induced pemphigus, desmocollin is the autoantigen

41) What percentage of dermatitis herpetiformis patients are asymptomatic but have findings consistent with celiac sprue on gastrointestinal biopsy?

A. 15%

B. 95% Correct Choice

C. 40%

D. 70%

E. 5%

Most patients with dermatitis herpetiformis have findings consistent with celiac disease on biopsy, but not all of them are symptomatic

42) Which neoplasm is the most common cause of paraneoplastic pemphigus?

A. CLL

B. Thymoma

C. Castleman's disease

D. Non-Hodgkin's lymphomaCorrect Choice

E. Retroperitoneal sarcoma

All of the above have been associated with paraneoplastic pemphigus with non-Hodgkin's lymphoma being the most common. Castlemans's disease is most common in children with paraneoplastic pemphigus

43) The defect in junctional epidermolysis bullosa occurs at the:

A. Lamina densa

B. Lamina lucidaCorrect Choice

C. Granular layer

D. Sublamina densa

E. Spinous layer

14

Junctional epidermolysis bullosa is an autosomal recessive disorder characterized by a defect in the lamina lucida. The protein uncein, a molecule which binds the gamma chain of laminin and a6b4/BPAg1, is absent in all forms of junctional EB. Uncein is normally found in the lamina lucida, along with lamin 1, laminin 5, laminin 6m, heparan sulfate proteoglycan, and fibronectin

44) Antibodies in chronic disease of childhood disease map to the:

A. Lamina densa

B. Lamina lucida and sublamina densaCorrect Choice

C. Sublamina densa

D. Lamina lucida

E. Basal layer

Immunoelectron mapping of chronic disease of childhood has shown binding within the lamina lucida as well as in the sublamina densa. This correlates with the finding of the 97-kDa antigen that is homologous to a portion of the BPAg2 molecule as well as a 280-290 kDa antigen in this disease. Some have suggested that the 280-290 kDa antigen is type VII collagen, but the former does not co-migrate with type VII collagen on Western blots

45) Th2-related cytokines include:

A. All of these answers are correct

B. IL10 Correct Choice

C. IFNgamma

D. IL10 and IFNgamma

E. IFNalpha

Atopic dermatitis is considered a disease in which a Th2 pattern predominates, especially early on. Th2 cytokines are IL4, IL5, IL6, IL10, IL13

46) An elderly gentleman with a history of hypertension and a thymoma, presents to the Emergency Room with oral and conjunctival erosions and hemorrhagic bullae on his hands and feet. These finds are seen in:

A. Toxic epidermal necrolysis

B. Sweet’s syndrome

C. Cicatricial pemphigoid

D. Erythema multiforme

15

E. Paraneoplastic pemphigusCorrect Choice

Paraneoplastic pemphigus is usually associated with cancers of lymphoid origin, including lymphoma, leukemia, thymomas, Castleman’s tumor. Clinically, this condition may present with intractable staomatitis, severe painful oral and conjunctival erosions

47) Herpes gestationis is most commonly associated with:

A. Hashimoto’s

B. Lupus

C. Rheumatoid arthritis

D. Diabetes

E. Grave’s Correct Choice

Autoimmune diseases are associated with herpes gestationis; Grave’s disease is the most common association

48) Which of the following adhesion molecules are important for maintaining adhesion between keratinocytes?

A. Immunoglobulin superfamily

B. Selectins

C. Integrins

D. Glycans

E. CadherinsCorrect Choice

Cadherins mediate cell adhesion and play a fundamental role in normal development. Calicum is required for the normal function of these adhesion molecules. There are two main subclasses, classic (E-, P-, N-) and desmosomal (desmoglein and desmocollin).

49) The dimethylglyoxime test is used to detect the presence of:

A. NickelCorrect Choice

B. Gold

C. Mercury

D. Silver

E. Latex

16

1% dimethylglyoxime is added to to the metal. If a red precipitate forms, there is >1:10000 nickel content

50) A one-day old infant presens with papules and pustules on the face, trunk, and proximal extremities. Palms and soles are spared. The patient is otherwise doing well. A biopsy shows numerous eosinophils. The diagnosis is:

A. Transient neonatal pustular melanosis

B. Herpes infection

C. Scabies

D. Erythema toxicum neanotorumCorrect Choice

E. Acropustulosis of infancy

Papule and pustules on an erythematous base appear on a healthy infant within 48 hours, and typically last 2-3 days in erythema toxicum neanotorum. The lesions may occur anywhere, but usually spare the palms and soles. Gram stain reveals numerous eosinophils. A 1 day-old infant would not have had a chance to acquire a scabies infestation. Acropustulosis of infancy typically presents at 3-4 months and the pathology shows vesicles with many neutrophils. A herpes infection would not show eosinophils. Transient neonatal pustular melanosis showsw sterile subcorneal pustules

51) Which type of porphyria manifests with peripheral neuropathy, colicky abdominal pain, but NO cutaneous symptoms?

A. Erythropoietic protopophyria

B. Variegate porphyria

C. Gunther's disease

D. Acute Intermittent PorphyriaCorrect Choice

E. Hereditary Copropophyria

Acute intermittent pophyria is caused by a defect in the enzyme porphobilinogen deaminase. Patients present with peripheral neuropathy and occasionally seizures, abdominal pain, and tachycardia. There are no skin changes as no dermal porphyrins are found

52) Gap junctions consist of:

A. Plectin

B. Filagrin

C. ConnexinsCorrect Choice

D. Laminin

17

E. Uncein

Gap junctions are protein channels that allow for communcation between cells. A connexon of one cell is joined to that of an adjacent cell to form an intercellular channel consisting of 12 connexin subunits. Each intercellular channel provides a channel that interconnects the cytoplasm of the apposed cell directly and permits the passage of ion and other small molecules between adjacent cells.

These protein channels that make up the gap junctions consist of two “hemi-channels” or connexons. One connexon resides in the membrane of one cell and it aligns and joins the connexon of the neighboring cell, forming a continous aquaeous pathway by which these ions and small molecules can freely pass from one cell to the other. Each hemi-channel or connexon consist of six proteins ( hexamer) called connexins

53) Which steriod screening agent should be used when an allergic contact dermaititis is suspected to hydrocortisone?

A. Glutaral

B. Budesonide

C. Hydrocortisone-17-butyrate

D. Tixocortol-21-pivalateCorrect Choice

E. Benzalkonium chloride

Tixocortol-21-pivalate is a group A steroid and screens for allergies to hydrocortisone, prednisone, and methylprednisolone. Budesonide screens for groups B and D steroids, and hydrocortisone-17-butyrate screens for group D steroids

54) Paraneoplastic pemphigus:

A. Is most often seen in association with lung cancer

B. Does not remit even if the cancer is excised completely

C. Is characterized by a pathognomonic 250 kDa antigen

D. All of these answers are correct

E. May be caused by a benign neoplasm Correct Choice

Paraneoplastic pemphigus can be caused by lymphoma as well as other malignancies. It can also be secondary to benign thymomas and Castleman’s disease. Numerous antigens have been found, including desmoplakin I and II. Desmoplakin I and II may be antigenic in Stevens-Johnson syndrome

55) Direct immunofluorescent studies in a patient with bullous pemphigoid is most likely to show:

A. Linear C3 at the basemement membraneCorrect Choice

B. C3 in the dermal papillae

18

C. Granular IgA in dermal papillae

D. Intercellular IgG4 throughout the epidermis

E. Linear IgA at the basement membrane

In bullous pemphigoid, the antigenic targets are believed to be BPAg1 and BPAg2-NC16A domain. These proteins are located in the hemidesmosome. Direct immunofluorescent studies reveal linear basement membrane C3in approximately 95% of patients, and IgG4 in approximately 80%. Linear IgA is found in linear IgA and chronic bullous deiseasaeof childhood. Granular IgA and C3 in the dermal papillae is found in dermatitits herpetiformis. Intercellular IgG4 throughout the epidermis is found in pemphigus vulgaris

56) Bullous lesions are seen in:

A. Tertiary syphilis

B. Primary syphilis

C. Secondary syphilis

D. Congenital syphilis Correct Choice

E. All of these answers are correct

Congenital syphilis, but not other forms of syphilis, can occasionally present with bullae

57) Papillary dermal deposits of IgA and a papillary dermal infiltrate of neutrophils is diagnostic of:

A. Bullous pemphigoid

B. Linear IgA dermatosis

C. Sweet's syndrome

D. Leukocytoclastic vasculitis

E. Dermatitis herpetiformisCorrect Choice

Dermatitis herpetiformis is an uncommon chronic, pruritic papulovesicular dermatitis occurring most commonly in young to middle-aged adults. Common sites of predilection include the buttocks, elbows, knees, scapula and scalp. Typical histologic features include accumulation of neutrophils at the tips of dermal papillae, sometimes admixed with eosinophils. Direct immunoflorescence (DIF) reveals granular deposits of IgA within the dermal papillae.As the name implies, linear IgA disease is characterized by linear IgA deposition along the basement membrane zone with DIF in 100% of cases. The pattern of direct immunoflorescence in bullous pemphigoid is linear C3 deposition at the dermoepidermal junction in nearly 100% of cases and IgG in 65-95% of cases. Sweet's syndrome is not characterized by a pattern with DIF. Under light microscopy, a dense perivascular infiltrate of neutrophils is seen assuming a bandlike pattern throughout the papillary dermis associated with prominent dermal edema. Leukocytoclastic vasculitides are characterized by a perivascular neutrophilic infiltration with karyorrhexis, leukocytoclasis, fibrinoid degeneration, and endothelial swelling

19

58) Which type of porphyria disease is most likely to be associated with cholelithiasis?

A. Acute intermittent porphyria

B. Hereditary coproporphyria

C. Congenital erythropoeitic porphyria

D. Variegate porphyria

E. Erythropoetic protoporphyriaCorrect Choice

Erythropoeitic protoporphyria is caused by a defect in the enzyme ferrrochetalase. Patients present with immediate photosensitivity and subsequently develop waxy scarring on the face, hands and knuckles. In addition to abdominal pain, cholelithiasis and liver disease may also occur. The porphyria diseases associated with abdominal pain are acute intermittent porphyria, hereditary coproporphyria and variegate porphyria. Congenital erythropoeitc porphyria is associated with splenomegaly

59) Atopic dermatitis is associated with all except:

A. Lchthyosis hystrix Correct Choice

B. Central facial pallor

C. Pityriasis alba

D. Hyperlinear palms

E. Nipple eczema

Icthyosis vulgaris (not hystrix) is associated with atopic dermatitis as one of the minor criteria of Hanifin

60) Antibodies against type VII collagen are seen in:

A. Epidermolysis bullosa acquisitaCorrect Choice

B. Cicatricial pemphigoid

C. Pemphigus erythematosus

D. Epidermolysis bullosa simplex

E. Bullous pemphigoid

Type VII collagen is present in the basement membrane of stratified squamous epithelia in the anchoring fibrils. It is the target antigen in several blistering disease including epidermolysis bullosa acquista, bullous lupus erythematosus, dominant and recessive dystrophic epidermolysis bullosa

61) This is associated with deafness:

20

A. Cadherin

B. Desmoplakin

C. Claudin

D. Desmin

E. Connexin Correct Choice

Connexin 26 is associated with PPK and deafness. Mutations in this same connexin is associated with Vohwinkel’s and KID syndromes

62) Patients with Senear-Usher syndrome are most likely to present with:

A. Erythematous crusts and hyperkeratotic lesions on the nose, ears, cheeks, scalp, and chestCorrect Choice

B. Transient vesicles on the oral mucosa

C. Erythematous papules and plaques around the umbilicus

D. Erythema multiforme-like oral ulcerations which are severe

E. Severely pruritic grouped vesicles symmetrically distributed primarily on extensor surfaces

Senear-Usher syndrome, also known as pemphigus erythematosus, is thought to be an overlap between lupus erythematosus and pemphigus foliaceous. The histology resembles that of pemphigus foliaceous with linear IgG at the dermoepidermal junction. 80% of patiens have a positive lupus band

63) The vector of fogo selvagem may be:

A. Triatoma

B. Mus

C. Simulium Correct Choice

D. Ornithodorus

E. Cimex

Fogo selvagem is considered to be an endemic form of pemphigus foliaceus, first described in Brazil, in rural areas where Simulium (black fly) is often found. Subsequently, other rural South American areas have had clusters of affected patients

64) Formaldehyde releasers include all except:

A. Methylchoroisothiazolinone Correct Choice

21

B. DMDM hydantoin

C. Germall

D. Dowicil

E. Quaternium – 15

Methylchloroisothiazolinone is also known as Kathon CG and it is a preservative. Germall, quaternium 15 (dowicil 200), DMDM hydantoin, and others are formaldehyde-releasing preservatives

65) Which of the following immunosuppressive agents has been most effective in cicatricial pemphigoid?

A. Azathioprine

B. Cyclophosphamide Correct Choice

C. Cyclosporine

D. Methotrexate

E. Mycophenolate mofetil

Cicatricial pemphigoid is a heterogeneous group of subepithelial blistering diseases involving the mucous membranes and skin. The treatment of cictracial pemphigoid is predicated upon the extent, severity, and location of disease. Most regimens used are empiric and are based on clinical experience. With severe ocular involvement, most experts recommend aggressive treatment with the combination of cyclophosphamide and steroids

66) Bullous lupus erythematosus is most commonly associated with antibodies to:

A. Plectin

B. Desmoglein I

C. Type VII collagenCorrect Choice

D. Laminin 5

E. Type XII collagen

Type VII collagen is found in the sublamina densa and patients with bullous lupus erythematosus have been found to have antibodies to this protein. The histology can resemble that of dermatitis herpetiformis and DIF shows linear IgG, IgM, IgA and C3.

67) What is the most common site of involvement of this autoimmune blistering disease?

A. Nasopharyngeal mucosa

22

B. Eyes

C. Genitalia

D. Skin

E. Oral mucosaCorrect Choice

Cicatricial pemphigoid is a heterogeneous group of diseases with characteristic involvement of the oral mucosa, eyes, skin. Rarely, it can also involve the nasopharyngeal mucosa, external genitalia, esophagus, and anus. The oral mucosa is the most common site of involvement

68) What is the primary irritant found in garlic and onions?

A. DiallyldisulfideCorrect Choice

B. Glycoside ranunculin

C. Capsaicin

D. Glochids

E. Calcium oxalate

Garlic is a potent irritant that can cause 2nd and 3rd degree burns on the fingertips of homemakers and chefs. The irritant responsible for this reaction is diallyldisulfide

69) The ocular form of cicatricial pemphigoid is most likely to be associated with antibodies to:

A. BPAg1

B. Beta-4-integrinCorrect Choice

C. BPAg2-NC16A

D. Laminin 5

E. Plectin

Antibodies to beta-4-integrin are associated with ocular cicatricial pemphigoid. Laminin 5 is associated a variant of cicatricial pemphigoid that is associated with malignancy. BPAg1 is the antigen in bullous pemphigoid, while BPAg2-NC16A is associated with both bullous pemphigoid and herepes gestationis. Mutations in plectin are associated with epidermolysis bullosa acquisita with muscular dystrophy

70) Transient bullous disorder of childhood has a defect in:

A. Plectin

B. Collagen VII Correct Choice

23

C. Alpha6-integrin

D. BPAg2

E. Epiligrin

Transient bullous dermolysis of the newborn may be a forme fruste/variant of dominant dystrophic EB. Mutations have been found in type VII collagen

71) Nickel can be detected in jewelry by applying:

A. Dowicil

B. Quinone

C. Thiocyanate

D. Dimethylglyoxime Correct Choice

E. Methylchloroisothiazolinone

Dimethylglyoxime application to metals containing nickel will show a pink color. Methylchloroisothiazolinone is Kathon CG, a preservative. Dowicil is a formaldehyde-releasing preservative. Primin is a type of quinone, and it is the allergen in primrose (Primula obconica). Thiocyanates are the irritating substances in garlic

72) Leiner’s disease (erythroderma desquamativum) is associated with:

A. C5-9 deficiency

B. Numerous infections

C. Numerous infections and diarrhea Correct Choice

D. All of these answers are correct

E. Diarrhea

Leiner’s disease is associated with deficient C5 and possibly C3. Babies with this disease are prone to diarrhea, infections (sepsis), anemia, and a generalized seborrheic dermatitis-like rash

73) Which of the associated antigens for this condition has been associated with colon cancer?

A. Beta-4 integrin

B. Anti-epiligrinCorrect Choice

C. 97 kD linear IgA dermatosis antigen

24

D. Desmoplakin

E. Bullous pemphigoid antigen 2

While the oral mucosa is the most common site for cicatricial pemphigoid, ocular involvement is very common. Clinical manifestations may include shortened fornices, symblephera, ankyloblephera. The majority of of ocular antigens are thought to reside in the cytoplasmic domain of beta-4 integrin

74) Which is incorrect?

A. Sesquiterpene lactones : artichokes

B. Urushiol : anacardia

C. Usnic acid : lichen

D. Diallyl disulfide : fig Correct Choice

E. Tulipalin : alstroemeria

Tulipalin A is a byproduct of tuliposide A metabolism, and it is the allergen in alstroemeria, the Peruvian lily, and tulips. Urushiol is the allergen in Toxicodendron plants as well as several other cross-reactors including cashew nut shells (Anacardium occidentale). Artichokes are in the family Asteraceae (formerly Compositae); this family is allergenic secondary to sesquiterpene lactones. Lichens contain usnic acid. The fig tree is in the family Moraceae, which is one of the plant families that can cause phytophotodermatitis

75) Clumped tonofilaments are seen on electron microscopy in:

A. Vohwinkel’s syndrome

B. Gunther’s

C. Naxos disease

D. Dowling-Meara Correct Choice

E. Weber-Cockayne

Clumped tonofilaments (keratin intermediate filaments) are seen in EB simplex subtype Dowling-Meara. Weber-Cockayne is a subtype of EB simplex with trauma-induced blistering on the soles of the feet and occasionally palms

76) The most common cause of contact dermatitis in the United States is:

A. Nickel

B. Hair dyes

25

C. Rubber

D. ToxicodendronsCorrect Choice

E. Nail lacquers

The most common cause of contact dermatitis in the USA are (in order of most to least common): toxicodendrons (poison ivy, oak, or sumac), nickel, fragrance, thimerosal, quarternium-15, neomycin, formaldehyde and the formaldehyde-releasing preservatives, bacitracin, and rubber compounds

77) The antigen in linear IgA is:

A. Laminin 5

B. 97kDa part of BPAg2Correct Choice

C. Alpha-6, beta integrin

D. Plectin

E. BPAg1

The antigen in linear IgA and its variant, chronic bullous disease of childhood, is the 97kDa part of BPAg2. BPAg1 is the antigen in bullous pemphigoid. Plectin is defective in EB simplex with muscular dystrophy. Laminin 5 is defective in junctional EB and alpha 6, beta integrin is defective in junctional

EB with pyloric atresia.

78) Bullous pemphigoid antigen 1 (BPAg1) is a member of this family:

A. Integrin

B. Selectin

C. Plakin Correct Choice

D. Intermediate filament

E. Cadherin

The plakin family includes desmoplakin I and II, BPAg1, envoplakin, periplakin

79) Which of the following is the most common cause of contact dermatitis due to a formaldehyde releasing preservative?

A. Thimerosal

B. Paraphenylenediamine

26

C. Paraben mix

D. Quaternium 15Correct Choice

E. Imidazolidinyl urea

Quaternium 15 is the primary cause of contact dermatitis among formaldehy-releasing preservatives. Other formaldehyde-releasing preservatives include imidazolidinyl urea, diazolidinyl urea, DMDM hydantoin, Bronopol, Cyanobutane, Ethyleneurea melamine formaldehy resin (found in permanent press clothing), and dimethylol dihydroxyethyleneurea. Paraben mix (#1 preservative in topicals), thimerosal (a type of mercurial antiseptic), and paraphenylenediamine (hair dye) are non-formaldehyde releasing preservatives

80) Bullous diabeticorum typically presents on the:

A. Chest

B. Groin

C. Arms

D. Face

E. LegsCorrect Choice

Bullous diabetocorum presents as tense blisters on the legs. They are typically non-inflammatory and appear suddenly

81) A 60 year old gentleman presents with a recurrent pustular eruption. Biopsy demonstrates subcorneal pustules with abundant neutrophils and a serum protein electrophoresis shows a monoclonal IgA gammopathy. The autoantigen responsible for this condition:

A. Plakoglobin

B. Desmoglein I

C. Desmocollin ICorrect Choice

D. Beta 4 integrin

E. Desmoplakin

Sneddon-Wilkenson (subcorneal pustular dermatosis) is a variant of IgA pemphigus. Clinically, patients have pustules arranged in annular and serpiginous pattern on the abdomen, axilla, and groin. The antigen is desmocollin 1 and 2. Treatment options include acitretin and dapsone

82) The anchoring plaque is composed primarily of:

A. Plectin

27

B. Connexins

C. Collagen IVCorrect Choice

D. Collagen XVII

E. Collagen VII

Collagen IV is located in the dermal matrix and forms the anchoring plaque. The anchoring plaque serves to anchor the lamina densa to the dermis via collagens 1,3 & 5.

83) Which type of epidermolysis bullosa has the greatest risk of developing squamous cell carcinomas?

A. Hallopeau-Siemens type of recessive dystrophic EBCorrect Choice

B. Herlitz

C. Dowling-Meara

D. Weber-Cockayne

E. EB Simplex with muscular dystrophy

Dystrophic EB is due to a defectin collagen 7, leading to decreased or absent anchoring fibrils in the sublamina densa. The three types of dominant dystrophic EB include Hyperplastic cockayne-Touraine, Albopapuloid Pasini, and Bart's. The Recessive form of dystrophic EB is also known as Hallpeau Siemens and patients present at birth owith generalized bullae which lead to erosions and atrophic scarring, mitten deformities, flexion contractures, oral and esophageal scarring and strictures and dysplastic teeth. There is an increased risk of squamous cell carcinomas

84) Fecal isocoproporphyrin is seen in:

A. Acute intermittent porphyria

B. Coproporphyria

C. Variegate porphyria

D. Harderoporphyria

E. Porphyria cutanea tarda Correct Choice

Fecal isocoproporhyrin is characteristic of porphyria cutanea tarda

85) Herpes gestationis is most commonly associated with:

A. Grave's diseaseCorrect Choice

B. Lupus

28

C. Multiparity

D. Inflammatory bowel disease

E. Lymphoma

Herpes gestationis (HG) typically occurs in the second or third trimester, and clinically presents as urticarial papules and plaques around the umbilicus which progress to involve the rest of the body. HG has been associated with Grave's disease

86) Pinus palustris is the source of:

A. Urea

B. D-limonene

C. Quinones

D. Lactones

E. Abietic acid Correct Choice

Abietic acid is the allergenic component of rosin (colophony). D-limonene is found in tea tree oil. Primin is a quinone; it is found in the primrose (Primula obconica). Abietic acid is found in rosin

87) Dermatitis herpetiformis is associated with:

A. HLA-B27

B. HLA-DQ1

C. HLA-Cw6

D. HLA-DR3 Correct Choice

E. HLA-DR4

HLA DR3 and DQ2 are associated with dermatitis herpetiformis. HLA B27 is associated with psoriasis with spondylarthropathy while HLA Cw6 is associated with psoriasis

88) Common causes of drug-induced linear IgA:

A. Penicillin

B. All of these answers are correctCorrect Choice

C. Vancomycin

D. Captopril

29

E. Cephalosporins

Linear IgA disease that is induced by drugs is most commonly secondary to vancomycin. Other implicated drugs include other antibiotics and captopril

89) Mutations in beta-catenin are most commonly associated with:

A. Bullous pemphigoid

B. Ectodermal dysplasia with skin fragility

C. PilomatricomasCorrect Choice

D. Naxos disease

E. Ocular cicatricial pemphigoid

The armadillo family of proteins constitute of group of proteins which function in cellular adhesion. These include beta catening, plakoglobin and plakophilins. Mutations in beta-catenin have been associated with some pilomatricdomas and colorectal carcinomas. Naxos disease has been linked to a mutation in plakoglobin, while ectodermal dysplasia with skin fragility has beenlinked to a mutation in plakophilin 1. Ocular cicatricial pemphigoid is associated with antibodies to beta4-integrin

90) This disease is inherited in an X-linked recessive manner:

A. Chronic granulomatous disorder Correct Choice

B. Dowling-Meara

C. Mongomery’s syndrome

D. Treacher-Collins

E. Job’s syndrome

Chronic granulomatous disorder is inherited in an X-linked recessive manner, as is Wiskott-Aldrich. Job’s syndrome is autosomal dominant. Dowling-Meara is a subtype of EB simplex, with autosomal dominant inheritance. Mongomery’s syndrome is xanthoma disseminatum. Treacher Collins syndrome is also known as mandibulo-facial-dysostosis

91) The C-terminal domain of BPAg2 is targeted in:

A. IgA pemphigus

B. Pemphigoid gestationis

C. Duhring’s disease

D. Bullous pemphigoid

30

E. Cicatricial pemphigoid Correct Choice

The C-terminal domain of BPAg2 is targeted in cicatricial pemphigoid. The NC16A domain of BPAg2 is targeted in bullous pemphigoid

92) Which pair is incorrect?

A. Antabuse : thiuram

B. Eyedrops : thimerosal

C. Ear drops : neomycin

D. Theophylline : ethylenediamine

E. Cobalamin : balsam Correct Choice

Cobalamin is Vitamin B12; cobalt is a component of Vitamin B12. Balsam of Peru is found in fragrances

93) Which pair is incorrect?

A. Glyceryl thioglycolate : acid permanent wave

B. Permethrin : chrysanthemum

C. Wrinkle-resistance : formaldehyde

D. Chewing gum : colophony

E. Parabens : artichokes Correct Choice

Wrinkle-resistant clothing is treated with formaldehyde. Chewing gum contains rosin (colophony). Parabens are preservatives. Artichokes are a member of the family Asteraceae (formerly Compositae). Glyceryl thioglycolate and methylchloroisothiazolinone are found in acid permanent wave products. Permethrins are synthetic pyrethroids that are similar to pyrethrins derived from the Asteraceae family. Permethrins can cross-react with allergy to chrysanthemums

94) Which of the following is LEAST LIKELY to cross react with Toxicodendron plant dermatitis?

A. Japanese lacquer tree

B. Mango rind

C. KiwiCorrect Choice

D. Cashew nut

E. Gingko tree

31

The Toxicodendron group of plants is the #1 cause of contact dermatitis in North America. This group of plants includes poison ivy, poison oak, and poison sumac. Because the Toxicodendron plants belong to the Anacardiaceae family, cross reactions can occur with related plants and substances such as braqzilian pepper, cashew nut, cashew oil, gingkgo tree, indian marking nut, Japanese lacquer tree, mango, and Rengas tree. Kiwi can cross react with patients who are latex-allergic

95) This medicine causes degranulation of mast cells

A. All of these answers are correctCorrect Choice

B. opiates

C. polymixin B

D. ASA

E. NSAIDs

Mast cell degranulators include NSAIDs, ASA, opiates, polymixin B, radiocontrast, tubocurarine, succinylcholine, and others

96) The rate limiting step in the porphyria pathway is mediated by the enzyme:

A. Porphobilinogen deaminase

B. ALA synthaseCorrect Choice

C. ALA dehydratase

D. Ferrochetalase

E. Uroporphyrinogen decarboxylase

ALA synthase mediates the first and rate-limiting step in the heme synthesis pathway. This step occurs in the mitochondria and allows for the conversion of Succinyl coA + glycine to delta aminolevilinic acid

97) At what level is the blister separation plane in linear IgA dermatosis?

A. Suprabasal layer

B. Lamina densa

C. Basal layer

D. Lamina lucidaCorrect Choice

E. Granular layer

32

The cleavage in linear IgA dermatosis (LAD) typically occurs in the lamina lucida as the target antigen is the 97 kD cleaved portion of bullous pemphigus antigen II (BPAgII). A variant of LAD may separate in the sublamina densa, with a target antigen of the type VII collagen in the anchoring fibrils. This condition may also be induced by ingestion of certain medications including vancomycin, lithium and diclofenac

98) Which of the following forms of epidermolysis bullosa is autosomal recessive?

A. Hyperplastic cockayne-touraine

B. Dowling-Meara

C. Weber-Cockayne

D. EB simplex with muscular dystrophy

E. Junctional EB with pyloric atresiaCorrect Choice

The forms of junctional epidermolysis bullosa are inherited in an autosomal recessive fashion. These include Herlitz, non-Herlitz, JEB wityh pyloric atresia, JEB inversa, and GABEB. recessive dystrophic EB(Hallopeau-Siemens) is also a recessive subtype of dystrophic EB. EB simplex is typically inherited in an autosomal dominant fashion. Hyperplastic cockayne-touraine is a subtype of dominant dystrophic EB

99) Allergic contact dermatitis is characterized histologically by:

A. Parakeratosis

B. Psoriasiform dermatitis

C. Lichenoid infiltrate

D. Granuloma

E. SpongiosisCorrect Choice

Spongiosis refers to the accumulation of edema fluid between keratinocytes, in some cases progressing to vesicle formation. The epidermis acquires a "spongy" appearance. This histopathologic pattern of inflammation is usually accompanied by an infiltrate of lymphocytes within the epidermis and around superficial vessels. In addition to spongiosis, allergic contact dermatitis is typically accompanied by eosinophils

100) Cicatricial pemphigoid can be induced by:

A. Aminoglycosides

B. Ciprofloxacin

C. Vancomycin

D. Clonidine Correct Choice

33

E. Benzene

Clonidine is a cause of drug-induced cicatricial pemphigoid. Other common causes includee sulfa drugs and thiol-containing drugs

101) Patients with epidermolysis bullosa acquisita have:

A. Antibodies to collagen VII Correct Choice

B. A defect in plectin

C. A defect in laminin 5

D. Antibodies to collagen XVII

E. A defect in collagen XVII

Epidermolysis bullosa acquisita (EBA) classically presents in adulthood as noninflammatory trauma-induced bullae that heal with scarring, especially on the hands and feet. Histology shows a subepidermal blister (usually pauci-inflammatory); DIF shows linear IgG at the basememt membrane; salt-split skin shows antibodies at the "floor". Patients hae antibodies to type VII collagen

102) A 35 year-old dentist presents with tingling in his fingertips. What allergen is most likely to cause this dermatitis?

A. Methyl methacrylateCorrect Choice

B. Thiuram mix

C. Ethylenediamine dihydrochloride

D. Paraphenylenediamine

E. Colophony

Methyl methacrylate is found in synthetic resins, dentures, artificial, nail adhesives, and acrylic bone cement. This allergen may penetrate through the gloves to the fingertips and most often affects the first three fingers. In addition to dermatitis, it also causes a peripheral neuropathy

103) Fiberglass dermatitis can be prevented by:

A. Water

B. Talcum powder Correct Choice

C. Alkali

D. Sodium chloride

34

E. Acetic acid 5%

Talcum powder application causes fiberglass spicules to slide off skin

104) Characteristic eosinophilic abscesses are seen in:

A. Herpes gestationis

B. Pemphigus vegetans Correct Choice

C. Incontinentia pigmenti

D. Paraneoplastic pemphigus

E. Bullous drug

Eosinophilic abscesses with minimal to no spongiosis in a hyperplastic epidermis are characteristic of pemphigus vegetans

105) Antibodies to which antigen are most likely responsible for this disease?

A. Desmoglein I

B. Keratin 5

C. Bullous pemphigoid antigen IICorrect Choice

D. Plakoglobin

E. Desmocollin

The clinical appearance of tense bullae and urticarial plaques is suggestive of bullous pemphigoid. Bullous pemphigoid antigen II is a transmembrane protein in the hemidesmosome. Antibodies to this antigen are pathogenic in bullous pemphigoid

106) Which of the following proteins is a 160kDa cadherin?

A. Envoplakin

B. Plectin

C. Desmoglein 3

D. Desmoplakin I

E. Desmoglein 1Correct Choice

Desmogleins and desmocollins belong to the cadherin family of proteins, which are calcium-dependent adhesion molecules. Desmoglein I is a 160kDa cadherin, while Desmoglein 3 is a 130 kDa cadherin. Desmoplakin, envoplakin, and plectin belong to the plakin family of adhesion proteins

35

107) Antibodies in some forms of Stevens-Johnson bind to:

A. Desmoglein 3

B. Desmoplakin I Correct Choice

C. Desmoglein 1

D. Plakoglobin

E. Desmoplakin I and desmoglein 3

Antibodies against desmoplakin I and II have been found in Stevens-Johnson

108) Which pair is not associated with allergic cross-reactivity?

A. PABA : procaine

B. Thimerosal : piroxicam

C. Thiuram : sulfa drugs Correct Choice

D. Balsam of Peru : cinnamon

E. Ethylenediamine : hydroxyzine

Thiurams may cross-react with Antabuse (disulfiram

109) Latex allergy can cross-react with all except:

A. Kiwi

B. Avocado

C. Banana

D. Chestnut

E. Artichoke Correct Choice

Latex allergy can cross-react with avocados, bananas, kiwis, chestnuts, and other foods. Artichokes are a member of the Asteraceae (formerly Compositae) family

110) Patients with latex allergy are LEAST LIKELY to develop a reaction to:

A. CashewCorrect Choice

B. Chestnut

36

C. Avocado

D. Banana

E. Kiwi

Although rare, cross-reactivity in latex-allergic patients has been demonstrated to banana, kiwi, avocado, passion fruit, and chestnut. Cross-reaction to cashew has NOT been reported

111) Which of the following is known as "prickly heat"?

A. Miliaria rubraCorrect Choice

B. Grover's disease

C. Miliaria profunda

D. Miliaria crystallina

E. Fox-Fordyce disease

Miliaria are caused by occusion of ecrine sweat glands. Miliaria crystalina are clear minute subcorneal vesicles with no inflammation. Miliaria rubra are red papules subepidermal vesicles with inflammation. Miliaria rubra is known as "prickly heat" as it presents after sweating, heat exposure, fever or occlusion. Miliaria profunda or pustulosa are red nodules or pustules with deeper inflammation. Fox-Fordyce disease is apocrine miliaria that is very pruritic and presents in axilla and anogenital area of women. Grover's disease is a papulovesicular eruption of the trunk that is pruritic and can occur after sun exposure or in bedridden patients with occluded backs. Histologically Grover's disease presents with small foci of acantholytic dyskeratotic cells in the suprabasal region

112) The best first line treatment for dermatitis herpetiformis is:

A. Prednisone

B. Colchicine

C. IVIG

D. Methotrexate

E. DapsoneCorrect Choice

The most effective drug for dermatitis herpetiformis is dapsonel. The dose varies between 50 and 300mg daily. Side effects include hemolytic anemia, leukopenia, methemoglobinemia, and rarely agranulocytosis or peripheral neuropathy. Sulfapyridine is also a very effective treatment for dermatitis herpetiformis

113) Ocular cicatricial pemphigoid has antibodies against:

A. Kalinin

37

B. Gamma-catenin

C. Beta4-integrin Correct Choice

D. Vinculin

E. Peripherin

Ocular cicatricial pemphigoid (CP) has autoantibodies against beta4-integrin. CP associated with malignancy has autoantibodies against epiligrin (laminin 5). CP with mucous membrane and skin findings often has autoantibodies against BPAg2

38