นพ. อินทนนท์ อ่ิมสุวรรณ โครงการจัดต้ังภาควิชาเวชศาสตร์ฉุกเฉิน

คณะแพทยศาสตร์ มหาวิทยาลัยธรรมศาสตร์

Ä On October 2, 20010 a 63-year-old Caucasian photo editor

working for a Florida newspaper o awoke early with nausea, vomiting, and

confusion and was taken to a local emergency room for evaluation

P His illness, which started on September 27 during a trip to North Carolina

characterized by malaise, fatigue, fever, chills, anorexia, and sweats

, No history of headache, cough, chest pain, myalgias, dyspnea, abdominal pain, diarrhea, or skin lesions

� Patient was alert and interactive but spoke nonsensically

l He was not oriented to person, place, or time

t BT 39.2°C HR 109/min BP 110/80 RR 14/min

0 Initial pulmonary, heart, and abdominal examinations were normal

e No nuchal rigidity

ü CBC: Hct 45.7 WBC 9400 N 76% L15% Plt 109,000

C Na 132 K 3.5 Cl 110 HCO3 241 UA :no RBC,WBC

l prominent superior mediastinum and small left pleural effusion

0 WBC count 4,750/µL (81% neutrophils)µ RBC count 1,375/µLµ glucose 57 mg/dL (serum glucose 174

mg/dL) protein 666 mg/dL

ü Microscopy examination of the CSF showed many gram-positive bacilli

ü Shortly after admissionm He had generalized seizures and was

intubated for airway protection

ü The patient died on October 5 Autopsy findings

hemorrhagic mediastinal lymphadenitis immunohistochemical staining showed

disseminated B. anthracis in multiple organs

l a 59-year-old Caucasian man, contract employee at a U.S. State Department mail sorting facility that received mail from the District of Columbia postal facility became ill

ü He had drenching sweats 2 days of fever with chills,severe

myalgias w cough with scant white sputum substernal chest pain nausea, vomiting, abdominal pain

ü BT 38.2°C HR 116/min BP 120/70 RR 16/min

/ oxygen saturation 94% (room air)n He appeared ill and had decreased

breath sounds at the right base The rest of the examination was

unremarkable

ì Hematocrit 48.1%ì WBC count 9,500/mm3 ( 81% N, 9% L

9% M)m Platelet count 196,000/ mm3

9 Normal electrolytes and creatinine

� Widening mediastinum

Mediastinal adenopathy with evidence of hemorrhage

Normal lung parenchymaSmall bilateral pleural effusionsSuspected small pericardial effusion

° Intravenous penicillin c Rifampin c Ciprofloxacinc Vancomycin

Features that should alert possibility of bioterrorism-related outbreak

r A rapidly increasing disease incidence

(e.g., within hours or days) in a normally

healthy population

o An epidemic curve that rises and falls

during a short period of time

t especially with fever, respiratory, or

gastrointestinal complaints

Ä An endemic disease rapidly emerging at an uncharacteristic time or in an unusual pattern

Lower attack rates among people who had been indoorsespecially in areas with filtered air or closed

ventilation systems compared with people who had been outdoors

s Clusters of patients arriving from a single locale

Features that should alert possibility of bioterrorism-related outbreak

ü Large numbers of rapidly fatal casess Any patient presenting with uncommon

disease and has bioterrorism potential Pulmonary anthraxTularemiaPlague

Features that should alert possibility of bioterrorism-related outbreak

Ä The U.S. Public health system and primary healthcare providers must be prepared to address various biological agents

b pathogens that are rarely seen in the united states

r High-priority agents include organisms that pose a risk to national security

P Category A agentsCan be easily disseminated or transmitted

from person to personResult in high mortality rates and have the

potential for major public health impactMight cause public panic and social

disruptionRequire special action for public health

preparedness

� Anthrax (bacillus anthracis) i Botulism (clostridium botulinum toxin) 1 Plague (yersinia pestis) H Smallpox (variola major) a Tularemia (francisella tularensis) r Viral hemorrhagic fever

filoviruses [Ebola, marburg] arenaviruses [Lassa, machupo]

ü Biological weaponIn year 2001, USAnthrax was deliberately spread through the

postal system by sending letters with powder containing anthrax

22 cases of anthrax infection

P Bacillus anthracisi a gram-positive spore-forming

bacteriums “woolsorters'disease”a a disease of sheep, cattle, and horses

ü The spores are extremely hardy and can survive for years

s The disease is caused by exposure to the spores, not the bacilli in their vegetative state

ü The spores germinate into bacilli inside macrophages

n Releasing toxins protective antigenedema factorlethal factor

O cause edema and cell death

� Skin : cutaneous anthraxx Lung : inhalation anthrax

Breathing in anthrax spores from infected animal products like wool

l GI tract : gastrointestinal anthraxEating undercooked meat from infected

animals

ü Incubation periodd ranges from 1day to 8 weeks (average

5days) depending on the exposure route and dose 2-60 days following pulmonary exposure 1-7 days following cutaneous exposure 1-7 days following ingestion

0 the most lethal form of the disease f caused by inhaling spores into the lungsn the spores germinate and are

transported to the tracheobronchial lymph nodes

Initial phaseð flulike illness with malaisew nonproductive cough, chest discomfortu initial phase can be delayed for more

than a month in some patientss 50% of patients develop hemorrhagic

meningitis

ü Within 24 to 48 hoursh abrupt deterioration

Overwhelming sepsisDyspnea, stridorShockHemorrhagic mediastinitis

� Chest radiograph show a widened mediastinum and hilar adenopathy

Mediastinal widening and pleural effusion

ü CT chest is more sensitiveBloody pleural effusions consolidation of the lung fields

H Clinical diagnosisFlulike or septic illness

c A reason to consider anthrax in the first place Current outbreak, warning from authorities

, Sputum culture, gram stain, and blood cultures are not helpful until late in the course of the disease

ü Tests to confirm the diagnosis PCR for identification of anthrax markers

in pleural fluidi serologic detection of immunoglobulin to

protective antigene Immunohistochemical testing of biopsy

specimens

l Influenza

� spores are introduced into the skin through open wounds or abrasions

n After I.P. 1 to 5 days5 Begins as a papule usually on an

exposed areathe head, neck, or an upper extremity

o The papule may resemble an insect or spider bite and may itch

ü a papule progressing to form a large vesicle over the next several days

e Severe edema occurs around the lesion with regional lymphadenitis

m The lesions are not tenderm patient may or may not be febrile

Day 2 Day 4

Day 4 : edema Day 4 : Eschar formation

ü After about 1 weekü the lesion ruptures, forming a black

eschar r surrounding erythema and edema

increaseh The necrotic ulcer is usually painless

Ulcer and vesicle ringblack eschar

� Forearm lesion on day 7n vesiculation and ulceration of initial macular or

papular anthrax skin lesion

h Eschar of the neck on day 15, typical of the last day of lesion

ü In the next 2 to 3 weeksü the eschar sloughs off f the organism disseminates and the

patient dies

ü The mortality rate 20% without treatment 1% with treatment

t Antibiotics do not affect the course of local disease

e but are used to prevent dissemination and death

H Clinical diagnosis.i Confirmation

Culturing of the lesion, punch biopsy,or serologic testing

l Rare manifestations o The ingestion of insufficiently cooked,

contaminated meatt the spores are transported to regional

lymphatic tissuer I.P 2- 5 dayr The mortality rate is 50%

0 Present with sore throat and neck swelling from cervical and submandibular lymphadenitis

m The tonsils are frequently involvedi Fever and toxicityt Dysphagia t Respiratory distress

� Begins with nausea, vomiting, and fever e Hematemesise Ascitese Bloody diarrhea e Mesenteric lymphadenitisa Present with an acute abdomen

Rosen's Emergency Medicine: Concepts and Clinical Practice, 6th Ed

, Death usually results within 3 dayss The mortality rate was thought to

exceed 90%

� Inactivated, cell-free anthrax vaccinel There is a vaccine to prevent anthrax, but it

is not yet available for the general publica Anyone who may be exposed to anthrax

Certain members of the USArmed forcesLaboratory workersWorkers who may enter contaminated areasIn the event of an attack using anthrax as a

weapon, people exposed would get the vaccine

� Human-to-human transmission has not been reported with inhalational anthrax

t Airborne transmission does not occur, but direct contact with skin lesions may result in cutaneous infection

è Yersinia pestisà gram-negative bacterium c Zoonotic disease is transmitted to

humans by the bites of infected rodent fleas

Male Xenopsylla cheopis (oriental rat flea) engorged with blood. This flea is the primary vector of plague in most large plague epidemics in Asia, Africa, and South America

è suggestive of exposure to rodents, rodent fleas, wild rabbits, sick or dead carnivores, or patients with pneumonic plague.

a Incubation period is 1–6 days

, Specimensbubo aspirates, blood cultures, sputum

culture if pneumonic

o Microscopic identificationt culture confirmationt Serologic tests

fourfold change in antibody titer to f1 antigen between acute- and convalescent-phase sera

� Physicians should report all suspected plague cases to state or local health departments and/or consult with CDC to obtain information and access diagnostic services.

( Parenteral antibiotic therapy Streptomycin

O AlternativelyGentamicin

¤ Oral therapyDoxycycline

ì No vaccine is currently available in the united states.

i aimed at reducing contact with fleas and potentially infected rodents and other wildlife

ü Generated by the infected patient during coughing, sneezing, talking during

respiratory-care procedures

ü Healthcare providers and others should wear a surgical-type mask when within 3 feet of the infected patient

c Some healthcare facilities require a mask be worn to enter the room of a patient on droplet precautions

ü Maintained until patient has completed 72 hours of antimicrobial therapy

ü Maintaining spatial separation of at least 3 feet between infected patients and others when cohorting is not achievable.

r Avoiding placement in the same room with an immunocompromised patient.

m Special air handling is not necessary and doors may remain open

0 Prophylactic antibiotic treatment in person who exposure to bites of wild rodent fleas during an outbreaktissues of a plague-infected animalperson or animal with suspected plague

pneumonia

ü Contact precautionsWear clean gloves upon entry into patient

room.Wear gown for all patient contact and for all

contact with the patient’s environment.Require a gown be worn to enter the room of

a patient.Gown must be removed before leaving the

patient’s room.Wash hands using an antimicrobial agent

ü Healthcare facilities without patient rooms appropriate for Airborne Precautions

e should have a plan for transfer of suspected or confirmed smallpox patients to neighboring facilities with appropriate isolation rooms

Ð Fever, headache and stiff neck a sepsis and rash in meningococcemia

H N. meningitidis colonizes mucosal surfaces of nasopharynx

p direct contact with large droplet respiratory secretions from the patients or asymptomatic carriers

c Humans are the only host

H Patients with meningococcemia should be placed in respiratory isolation for at least 24 hours.

H Close contacts should receive antibiotic prophylaxis.

h Household, nursery school, and daycare center contacts

r Intimate contacts and health care workers with intimate exposure mouth-to-mouth resuscitation, intubation,suctioning

ü Rifampin, 10 mg/kg (up to 600 mg) orally every 12 hours for four doses

h The dose for infants younger than 1 month is 5 mg/kg.

. Rifampin discolors the urine r Contact lenses should be removed to

avoid permanent staining.

ü Ceftriaxone IM is effective against group A strains. 125 mg for children younger than 12 years 250 mg for those older than 12 yearsalternative for pregnant women and for

people in whom compliance cannot be ensured.

o Ciprofloxacin (500 mg orally)

È Meningococcal vaccine should be considered adjunct to prophylaxis in epidemics close contacts in sporadic cases

n The currently available vaccine is a quadrivalent vaccine containing purified capsular polysaccharides

for groups A, C, Y, W

ü No vaccine exists for group Bthe most prevalent serogroup in the United

States.

ü The quadrivalent vaccine is not recommended for routine use

r but should be administered tochildren 2 years of age older in high-risk groupsfunctional or anatomic asplenia terminal complement deficiency

ü The vaccine is currently administered to U.S. military recruits.

c Consideration in people traveling to endemic areas of the world such as sub-Saharan Africa.