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Resident Board Review. Joseph G. Timpone Jr. MD Georgetown University Hospital. Case One.
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Resident Board Review Joseph G. Timpone Jr. MD Georgetown University Hospital
Case One • An 80 y.o. female presents to the ER with a 3 day history of fatigue, abdominal cramps and bloody diarrhea. She denies any fevers and states that 10 days ago she was at a State Fair where she ate hotdogs, baked beans, coleslaw, and drank fresh apple cider. PEX: T=37 BP=140/90 P=100 ABDON: generalized tenderness LABS: WBC 12.0 HCT 19.0 PLTS 90,000 BUN/Cr 50/3.0 LDH 400 T.Bili 4.0
The most likely causative pathogen is: • A) S. aureus • B) B. Cereus • C) Norwalk virus • D) Listeria • E) E.coli O157:H7
E. Coli 0157:H7 • 21,000 Cases/YR; 6% pts. Develop HUS; 12% Mortality • Epidemiology: Young children & elderly; undercooked ground beef, unpasteurized milk, apple cider, water/vegetables contaminated with manure. • Incubation 3-4 days; ABD. cramping; bloody diarrhea (35 - 90%); fever uncommon (30%) • HUS: MAHA, Thrombocytopenia, ARF, can also see TTP. • Diagnosis: colorless, Sorbitol non-fermenting colonies on Sorbitol-Maconkey agar; 0157 Antisera Agglutination test. • Treatment: antibiotic use may increase risk of HUS
Case Two • A 30 y.o. healthy male is brought to the ER by his co-workers after a syncopal episode at work. In the ER the pt is arousable and noted to be afebrile. BP=70/40 P=40 EKG:3° Heart block. The pt states that he had recently returned from a hiking trip in New England one month ago.
The most likely causative pathogen is: • A) S. aureus • B) B. Burgdorferi • C) S. pyogenes • D) R. rickettsii • E) Coxsackie virus
Lyme Disease • North America: Borrelia Burgdorferi; Europe: B. Afzelii; Asia: B. Garinii • Southern New England, Middle Atlantic, Wisconsin, Minnesota, California • Ixodes Scapularis (Deer Tick): Nymphal stage must be attached for > 72 Hrs. to result in transmission • Stage 1: Viral-like illness associated with erythema migrans (60 - 80%). Expanding annular lesion with central clearing (at least 5cm by CDC criteria)
Acute Disseminated Lyme Disease (Stage 2) • Neurologic (occurs in 15% of patients) • Lymphocytic meningitis • Cranial Neuritis (Bell’s Palsy) • Motor-sensory polyradiculo neuritis • Mono-neuritis multiplex; myelitis • Cardiac (occurs in 5% of patients) • Atrio-ventricular block • Myo-pericarditis • Cardiomegaly/LV dysfunction (rare)
Chronic Lyme Disease (Stage 3) • Arthritis: (60% of untreated patients) • Oligo-articular/Mono-articular (Kness) • Treatment resistant arthritis in 10% • More common in North America • Neurologic • Cognitive dysfunction/encephalopathy • Polyneuropathy • More common in Europe • Chronic Skin Lesions • Acrodermatitis chronicum atrophicans • Associated with polyneuropathy
Lyme Disease: Diagnosis • 70% - 80% pts. have (+) IgM by 2 - 4 wks. • (+) IgG @ > 4 wks. • An isolated (+) IgM in the absence of a (+) IgG after one month of symptoms is likely a false (+) IgM • IgM and IgG can remain (+) for years • False (+): endocarditis, parvovirus B19, syphilis, EBV, SLE, RA • Elisa must be confirmed by W.B. • 5% of pts. In non-endemic area can be false (+) • PCR -> CSF; C6 Ab
Lyme Disease: Treatment • Stage 1 (E.M.): Doxycycline, Amoxicillin, Cefuroxime, Erythromycin for 14 - 21 days • Neurologic/cardiac: IV Ceftriaxone, Cefotaxime, PCN • Bell’s Palsy -> ? Doxycycline • Arthritis: Doxycycline x 30 days or IV Ceftriaxone x 14 - 28 days
Lyme Disease: Prevention • Prophylaxis: Doxycycline 200 mg x 1 dose has 87% efficacy for I. scaplilaris tick bits (0.4% vs. 3.2% - Doxy vs. placedo) • Recombinant OspA vaccine is 78% effective (0, 1, 12 mos. Or 0, 1, 2 mos.) Steere NeJM vol. 345; July 12, 2001 Nadelman , et.al NeJM vol. 345; July 12, 2002
Case Three • A 75 y.o. male with a history of HTN presents with a 1 wk history of fevers and fatigue. His PCP obtains some labs which reveal WBC 5.0 HCT 20.0 PLTS 40,000 AST 100 ALT 50 T.Bili. 3.5 LDH 525. The pt recently returned from his summer home in Nantucket.
The most likely causative organism is: • A) B. Burgdorferi • B) B. Microti • C) F. Tularensis • D) R. Rickettsii • E) E. Chaffeensis
Babesioses • Caused by B. microti and B . equi • Vector: Ixodes scapularis • N.E. (Cape Cod), California • Can be transmitted by transfusions • Elderly, splenectomized pts. • Fever, myalgias, H/A, hemolytic anemia, thrombocytopenia, elevated LFTs • Diagnosis: Peripheral smear, serology, PCR • Treatment: Quinine + Clindamycin; Atovaquone + Azithromycine; exchange transfusion • 20% co-infection with B. burgdorferi
Case Four • A 29 y.o. female presents to the ER with fevers, cough, and S.O.B. PEX: T 39.5 BP 110/80 P 120 O2 SAT. 88% CXR: diffuse pulmonary infiltrates LABS: WBC 25.0 HCT 55.0 PLTS 50,000 PT/PTT 16/60 The pt recently traveled to Arizona where she stayed on an Indian reservation to learn how to make jewelry.
The most likely causative organ • A) S. pyogenes • B) Listeria • C) C. Immitis • D) C. Neoformans • E) Hanta Virus
Hantavirus • Hanta virus: RNA virus; Bunyaviridae(Sin NOMBRE virus) • Hantavirus Pulmonary Syndrome • S.W. U.S. (New Mexico, Arizona, Utah, Colorado) has been reported in all States • Rodent exposure (Peromyscus maniculatus) • 4 Phages: febrile, shock, diuresis, convalescent • Clinical: fever, myalgias, cough, dyspnea, H/A, GI symptoms • Labs: leukocytosis, hemoconcentration, thrombocytopenia, prolonged PT/PTT • Rapidly progressive pulmonary edema with hypotension • Diagnosis: IFA of sputum, lung tissue • Treatment: ? Ribavirin • Case Fatality 76%
Case Five • A 32 y.o. male presents to the ER with fever and a ulcerative skin lesion on his arm. In the ER he has a T=103, and you notice ipsilateral axillary lymphadenopathy. Ten days ago he returned from a hunting trip where he killed and skinned a rabbit, fox, and deer.
The most likely causative pathogen is: A) B.burgdorferi B) B. anthracis C) Y. Pestis D) V. Vulnificus E) F. Tularensis
Tularemia: Francisella Tularensis • Gm (-) coccobacillus; requires cysteine for growth • Contact with infected animals (rabbits, squirrels, cats), inhalation, tick bite • Peak occurs with tick-borne exposure and hunting season • Southcentral and Southwestern United States- Oklahoma, Arkansas, Texas • Hunters, trappers, lab workers
Tularemia: Incidence • 1990-2000 – 1368 cases. • Approximately 124 cases/year reported to the CDC. • 56% cases were reported from Arkansas, Missouri, South Dakota, and Oklahoma. • Endemic on Martha’s vineyard. • 70% cases between May and August. (MMWR 2002 Mar 8; 51 (9) 182-184)
Francisella Tularensis • Small non-motile gm (-) cocci bacillus. • Can survive for weeks at low temperatures in water, moist soil, hay and decaying animal carcasses. • Voles, mice, rabbits, hares, squirrels are reservoirs. • Vectors: Ticks, flies, mosquitoes. • Human infection • Tick bites • Handling infected animals or animals products. • Ingestion. • Inhalation.
Tularemia: Clinical • 50% of patients with ulcer node disease • Patients develop ulcerative lesion at site of exposure which is associated with ipsilateral lymphadenopathy • Bacteremia, pneumonia, oculo-glandular disease • Pneumonia in gardeners on Martha’s Vineyard
Pneumonic Tularemia: Clinical • Fever and non-productive cough • 3 -5 day incubation period (range 1- 14 days) • CXR: pneumonia, pleural effusion, and hilar lymphadenopathy
Diagnosis, Treatment and Prevention • Diagnosis: grows on media enriched with cysteine; serology • Treatment: streptomycin, gentamicin, doxycycline, ciprofloxacin • P.E.P.: doxycycline or ciprofloxacin • Live attenuated vaccine: lab workers • Respiratory isolation not needed
Case Six • A 25 y.o. male presents to the ER with fevers, myalgias, LBP, nausea, and vomiting. In the ER he has a T=39.5, BP 80/40, P=120 and you notice a rash. Labs: WBC 25,000, HCT 45, PLT 40,000, BUN/Cr 40/2.2. The patient has returned from a camping trip in North Carolina one week ago.
The most likely causative pathogen is: A) B. burgdorferi B) S. Pneumoniae C) R. Rickettsii D) B. Microti E) Leptospiria
Rocky Mountain Spotted Fever • Caused by Rickettsia rickettsii • D. andersoni & D. variabilis • South Atlantic Coastal, western and south central states (North Carolina, South Carolina, Oklahoma, and Tennessee) • > 95% cases April - September • Dogs, wooded areas, males
RMSF: Clinical • Incubation 5 - 7 days (2 to 14 days) • Fever, H/A, malaise, nausea, vomiting, abd. pain • Rash: 1 - 5 days after onset of illness; macules on wrists & ankles; spread to trunk, palms, and soles; 10% pts. without rash • Thrombocytopenia, DIC, elevated LFTS@ ARF, ARDS
RMSF: Diagnosis & Treatment • Mortality: 5 - 25% • Diagnosis: DFA of skin biopsy - Serology • Treatment: Tetracyclines & chloramphenicol
Case seven • A 50 y.o. male with a history of hemachromatosis was brought in by his friends with fevers, diarrhea, & severe weakness. They had recently returned from a boating trip on the Chesapeake bay where they ate fresh crab and other assorted shellfish. On exam T=39 BP 70/40 P130
The most likely causative pathogen is: • A) S. aureus • B) Campylobacter jejuni • C) Shigella • D) Mycobacterium marinum • E) Vibrio vulnificus
Vibrio Vulnficus • Seawater or raw seafood/shellfish (oysters) • Chesapeake bay, Gulf coast (hurricane Katrina) • Liver disease, cirrhosis, hemachromatosis, ETOH • Septicemia with metastatic skin lesions • Diarrhea • rapidly progressive cellulitis • 50% mortality • Tetracycline/doxycycline; combination therapy with doxycycline + 3rd generation sephalosporin (ceftriaxone, cefotaxime)
A Trip to the Zoo Joseph G. Timpone, M.D. Division of Infectious Diseases
A 35 year old male is brought to a NYC E.R. with fevers H/A and (R) inguinal pain. In the E.R. he is noted to have T = 40oC, P = 120, and BP = 80/40. There is a 3x3 cm tense lymph node in (R) inguinal region. WBC = 25,000, PLTs = 60,000, Bun/Cr = 40/2.0.
The patient reports that he is visiting from Colorado where he is employed as a veterinarian. He has recently cared for a few sick cats, a rabbit and assisted in the birth of a calf.
The most likely causative agent would be: • a.) Sin Nombre Virus • b.) Francisella Tularensis • c.) Coxiella Burnettii • d.) Yersinia Pestis • e.) Bacillus Anthracis