case 11. a baby is born with a rash identical to that...
TRANSCRIPT
Case 11. A baby is born with a rash identical to that seen in
the baby. Questioning reveals that the mother had a febrile
illness during the second trimester of pregnancy. Examination
reveals diffuse raised purple skin lesions.
There is no pallor, jaundice, or cyanosis. The eyes are normal
externally, the heart has a 3/6 systolic murmur, and there is
enlargement of both the liver and the spleen. There is no LAP.
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What is your differential diagnosis?What would you like to know?
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CHEAP TORCHES:CHEAP TORCHES:C: ChickenpoxH: Hepatitis B/C/EE E t iE: EnterovirusA: AIDS (HIV)P: Parvovirus B19T: ToxoplasmosisO: other (GBS, Listeria, Candida,T.B, LCMV)R: RubellaR: RubellaC: CMVH: HSVE E thi l STD ( h Chl di l HPV)E: Everything else STD (gonorrhea, Chlamydia, ureaplasma, HPV)S: Syphilis
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In this case the rash was caused by rubella. The CRS may be associated with abnormalities affecting many organs: Ocular: cataract, microphthalmia, corneal opacityEar: deafnessH t CHDHeart: CHDBrain:MicrocephalyLiver: HepatitisLiver: HepatitisB.M: Anemia/ ThrombocytopeniaBone: Linear Lucencies in long bones (“celery stalk”appearance)
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The usual methods used to diagnose intrauterine infectionThe usual methods used to diagnose intrauterine infection
infection MethodRubella serologyCMV PCR on blood, urine viral cultureHIV DNA PCRLCMV SerologyS philis serolog (PCR)Syphilis serology(PCR)Toxo Serology
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CASE 12. A 6 y/0 girl complains of weakness and muscle pain and
tightness in her thighs and legs. About 1WK earlier she had a fever,
sore throat, and cough. On examination she can’t stand nor walk due
to weakness. Her thighs and calves are tender. Sensation and DTR
are NL. Examination of the back and upper limbs is N.L.
What might be wrong with her?
What would you like to know?
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The DDX is one of generalized weakness but preserved higher
function. This suggests a lower motor neuron lesion affecting her
lower limbs. The possible levels of disease should be considered
anatomically. It is useful to consider possible etiologies of disease
for each of these sites. The DDX should include the infectious and
noninfectious disease.
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Causes of acute flaccid weakness :Causes of acute flaccid weakness :
(A) Spinal cord : spinal shock/ transverse myelitis(A) Spinal cord : spinal shock/ transverse myelitis
(B) Ant. Horn cell: polio/ other enterovirus/ WNV(C) Peripheral nerve: GBS/ Diphtheria/ toxins/ Acute intermittent porphyria(C) Peripheral nerve: GBS/ Diphtheria/ toxins/ Acute intermittent porphyria
(D) Neuromuscular junction: botulism/ snake bites
(E) Muscle: myositis/ electrolyte disturbance (E) Muscle: myositis/ electrolyte disturbance
(F) Pseudo paresis (localized) : skeletal disease/ trauma/ osteomyelitis/ septic arthritis/ congenital syphilis
(G) Unknown mechanism: tick paralysis
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Th i d l d i hi i i di l The pain and muscle tenderness in this patient indicate muscle inflammation (myositis) as the cause of the weakness.
Acute muscle disease may be due to injury, inflammation (myositis), or a b li di d f l h k A i i i ll metabolic disorder, for example, heat stroke. Acute myositis is usually
caused by a viral infection such as influenza, enterovirus, HIV. This is referred to as benign acute childhood myositis, which is to be distinguished from the myositis accuring with dermatomyositis or distinguished from the myositis accuring with dermatomyositis or polymyositis, which have a prolonged course and can result in significant long‐term disability. Patient with benign acute myositispresent with acute onset of weakness and muscle pain and tenderness, present with acute onset of weakness and muscle pain and tenderness, must frequently affecting the calf muscles. The muscles may be swollen and the weakness may be profound. The dangers of myositis are respiratory failure and rhabdomyolysis.p y y y
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The diagnosis of myositis can be confirmed by the demonstration of The diagnosis of myositis can be confirmed by the demonstration of
elevated CPK activity in the serum. Myoglobinuria manifests as red,
clear urine (like rose wine) as opposed to red cloudy urine that clear urine (like rose wine) as opposed to red, cloudy urine that
occurs with hematuria. In this circumstance a urine dipstick test
that is positive for blood in the absence red cells on microscopy is that is positive for blood in the absence red cells on microscopy is
highly suggestive of myoglobinuria. A microbiological diagnosis of
the cause of myositis is not usually helpful, unless HIV infection is y y p
suspected. Treatment is primarily supportive, entailing analgesia
and a very high fluid intake. If myoglobinuria is present the urine
should be alkalinized to prevent injury to the renal tubules.
Monitoring of respiratory function is essential.
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Case 13. A 6 month – old boy presents with watery diarrhea and a tem. : 38.5 ْ◌ /c
Wh t i th t i t t t f th li i l l ti ? What is the most important aspect of the clinical evaluation?
What is the likely clinical diagnosis, and what are its possible causes?
What do you want to do?
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The most important question addresses the physiologic diagnosis, namely: what is his hydration status? The sign of dehydration are:
Decreased urine output Decreased urine output Sticky oral mucosa Decreased skin turgorS k Sunken eyes Tachycardia Poor peripheral perfusion and L.O.C. (shock)
what is the likely diagnosis? This is most likely a case of acute infectious diarrhea (acute GE). The possible causes are listed in next slide.
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Causes of acute infectious diarrhea
Virus: Rota Adeno Noro Astro Virus: Rota, Adeno., Noro., Astro.
Bacteria: salmonella, shigella, campylobacter, E. coli, yersinia, vibrio cholera vibrio parahaemolyticus clostridium difficile vibrio cholera, vibrio parahaemolyticus, clostridium difficile, clostridium perfringens
Parasites: giardia C Parvum cyclospora I belli E Histolytica B Parasites: giardia, C. Parvum, cyclospora, I. belli, E. Histolytica, B. coli
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lComplications:
1. Dehydration y
2. Metabolic and electrolyte disturbances
3. Bacteremia
4. HUS
5. Toxic encephalopathy
6. Chronic diarrhea
7. Colonic perforation
8. Reactive arthritis
9. GBS
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Causes of altered mental status in children who have or have had diarrhea Shock from dehydration Shock from dehydration Metabolic and electrolyte disturbance
Hypoglycemia H l i Hyperglycemia HyponatremiaHypernatremia
VascularStroke HUS
Iatrogenic (rapid correction of hypo/ hyper natremia)Complication of bacteremia (meningitis)shigellosisshigellosis
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Differential diagnosis of intestinal symptoms and signs Vomiting, no diarrhea
Gastritis Food poisoning Raised ICP Intestinal obstruction (intussusception)Parental infection
Hematochezia, no diarrheaMeckel’s diverticulumIntussusceptionPolypProfound upper intestinal bleeding
Bloody diarrheaMilk protein allergy IBD
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Epidemiological, clinical, and stool features associated with different Epidemiological, clinical, and stool features associated with different enteric infection, and tests used for their confirmation
Microorganism epidemiology clinical stool testMicroorganism epidemiology clinical stool testRotavirus winter acute no blood Ag Adenovirus ___ acute no blood tissue cultureNorovirus outbreak acute, vomiting no blood RT‐ PCRSalmonella animals, eggs, meat acute, fever ± blood, PUS culture Shigella day care, human acute, fever ± blood, PUS culture Campylobacter poultry acute ± blood, PUS culture
i i k bl d l yersinia pork acute ± blood culture Giardia daycare, water acute, chronic no blood micro./ Agcryptosporidium water, outbreak acute, chronic no blood micro./ AgCyclospora outbreak acute chronic no blood microCyclospora outbreak acute, chronic no blood microE. Histolytica travel acute, chronic blood micro. /Ag
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A ti i bi l th f t i i f ti Antimicrobial therapy of enteric infections
Microorganism antimicrobial agents Salmonella none unless bacteremia suspected Salmonella none, unless bacteremia suspected
ceftriaxone, TMP/SShigella ampicillin, TMP/S, ceftriaxone
azithromycin, fluoroquinoloneC l b j j i i h i fl i lCampylobacter jejuni azithromycin, fluoroquinolone
gentamicin, imipenemYersinia enterocolitica none, unless bacteremia suspected
ceftriaxone, TMP/S, gentamicince t a o e, /S, ge ta cE. Coli TMP/S, Flouroquinolone, rifaximinC. Difficile metronidazole, oral vancomycinGiardia metronidazole, nitazoxanideC P it idC. Parvum nitazoxanideCyclospora TMP/SI. Belli TMP/SE. Histolytica metronidazole, tinidazoley
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Case 14. A premature infant in the NICU being ventilated for HMD is noted to have temperature instability, dark red spots on the skin, and a swollen red ankle. Further examination reveals a 3/6 ejection systolic heart murmur, heard loudest at the upper sternal border. She has a venous and arterial vascular catheter in place The abdominal venous and arterial vascular catheter in place. The abdominal examination is NL.
What is the differential diagnosis?
What would you do? What would you do?
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Dark red spots on the skin suggest the possibility of hemorrhage or p gg p y ginfarctions of the skin. The red, swollen ankle suggests a septic arthritis or osteomyelitis. Tem. Instability suggests a systemic infection. A unifying diagnosis would be a systemic (bloodstream) bacterial or unifying diagnosis would be a systemic (bloodstream) bacterial or fungal infection associated with skeletal infection, and causing (a) a hemorrhagic tendency through the mechanisms of thrombocytopenia or DIC or (b) emboli due to IE. Nosocomial infection is important. The potential routes of infection are through:
Vascular access sites Vascular access sites
Lungs (intubation)
Intestine
U.T.I
*** Staph./ enterococci/ candida/ gram‐neg. bacilli
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Specific clinical evaluation
Examination of the optic fundi
Examination of all vascular access sites
U/A
B/C , CBC
Aspiration of ankle / skin lesions (gram stain/ culture)
Echo.
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Antimicrobial treatment
(a) Gram positive cocci (staph.): vancomycin+nafcillin+gentamicin. The reason for using both vancomycin and nafcillin is that for susceptible organisms, nafcillin is superior to vancomycin. However, the g , p y ,vancomycin is necessary in case the organism is resistant to β‐lactamAB (MRSA). Gentamicin accelerates the clearance of the staph. from the blood.
(b) Gram negative rods (enteric bacilli or p. aeruginosa): ceftazidime + amikacin/ gentamicin
(c) Yeasts: amphotericin B (in less severly ill patients with intravascular –(c) Yeasts: amphotericin B (in less severly ill patients with intravascular line – associated fungemia, and without endocarditis, and in whom the vascular line can be removed, fluconazole would be appropriate.
(d) If the gram stain does not reveal an ogranism initial treatment (d) If the gram stain does not reveal an ogranism, initial treatment should be directed at staph. and gram negative rods with vancomycin, nafcillin, gentamicin, or amikacin and a 3rd – generation cephalosporin cephalosporin.
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The gram stain from a skin aspirate of this patient shows gram positive
i i l h i l f h l i h ki cocci in clusters, the typical appearance of staphylococci. The skin,
B/C, ankle joint fluid grew out staph. aureus susceptible to methicillin.
Further evaluation revealed an aortic vegetation providing additional Further evaluation revealed an aortic vegetation, providing additional
evidence of IE. She was treated successfully with nafcillin.
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CASE 15. A 3 Y/O boy who broke out with chickenpox 5 days ago seems to be getting worse after initial improvement. He has a high fever, his skin
is red all over and he seems a little confused is red all over, and he seems a little confused.
Wh t i ht b th bl ? What might be the problem?
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The most likely problem is that this boy has developed a complication of y p y p pchikenpox. The most common complication is secondary bacterial infection of skin lesions with s. pyogenes or S. aureus. The child’s
illness is characterized by fever, confusion, and diffuse erythroderma. Given the apparent severity of the child’s condition and the
combination of clinical abnormalities, he probably has streptococcal/ combination of clinical abnormalities, he probably has streptococcal/ staphylococcal TSS.
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Further clinical evaluation should be directed at determining the adequacy of his perfusion and at finding a septic focus that might be drained. This is very important in TSS. Management should entail the drained. This is very important in TSS. Management should entail the following:
(a) Ensuring adequate perfusion with IV fluid and vasopressors, if necessary.
(b) Draining any focus of pus and sending specimens for gram stain and culture; a B/C should also be performed culture; a B/C should also be performed
(c) Antimicrobial therapy: vancomycin (MRSA) + oxacillin/ nafcillin/ cephazolin (strep. Pyogenes/ MSSA) + Clindamycin (halt toxin p ( p y g ) y (production)
(d) I.V.I.G
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