Transcript Psittacosis
Psittacosis GLOBAL HEALTH ELECTIVE LEON, NICARAGUA JUNE 8, 2010 DAVID MING, MD Case Presentation HPI: 7 year old male p/w dry cough + fevers + fatigue x 2 weeks and been persistent (+) decreased appetite but no chills/NS/wt loss Multiple sick contacts – 11 yo brother, father, and 3 other siblings all with similar acute febrile respiratory illness with onset around the same time Was in usual state of health before presentation 11 yo brother had been admitted with 8-10 days of similar sx but also developed SOB/DOE and difficulty with performing regular activities Was admitted 3 days earlier and developed fever + hypoxic respiratory failure in setting of ARDS Case Presentation HPI (continued): Father (40 yo) admitted 5 days earlier with similar illness but much milder than 11 yo brother – treated for CAP on ward PMHx: unremarkable Medications: none Immunizations: UTD (including BCG as infant) SHx: very rural community outside Leon (El Sauce) – lives with 6 siblings and parents in small 2 room home without running water or electricity; multiple animals in close proximity including chicken, birds, pigs, dogs, cattle, and rats; no recent disease outbreaks in the community and no recent travel Case Presentation VS – T 38.5 / P 100 / R 28 / Sat 95-97% RA / 21 kg Gen – AxOx3; NAD; comfortable and interactive young boy in NAD HEENT – no jaundice or pallor; MMM; OP clear Neck – supple; no LAD Lungs – coarse BS bilat; no signs of focal consolidation; no accessory muscle use CV – normal Abd – normal; no HSM; no ascites Skin – no rash and no jaundice Ext – 2+ pulses; no edema; nl CR <2 sec Neuro – non-focal Case Presentation 12.3 6 >--------< 517 38.5 Malaria smear neg Cl 106 / Cr 0.9 / Glu 90 INR 1.9 LDH 1053 Ucx/Bcx neg PPD neg AFB neg x 3 AST/ALT: 79 / 70 HIV Ab neg Leptospirosis IgM neg Dengue IgM neg Admission CXR Admission CXR – Older Brother Follow-Up – Comparing the Brothers Hospital Course Persistently febrile 39-40C without any significant increased WOB, HD changes, or clinical worsening – overall clinical appearance out of proportion to CXR findings Completed 7 days of empiric IV PCN G for possible leptospirosis without resolution of fever PPD for admitted 1 1 yo brother and both parents were negative Unable to obtain bronch/BAL 11 yo brother who was initially critically ill, eventually responded with complete resolution of CXR findings ~45 days after receiving ampho B + steroids Continues to improve but then develops relative bradycardia Hospital Course With patient remaining persistently febrile with atypical PNA clinical pattern (CXR out of proportion to essentially normal exam) + older brother with new relative bradycardia + no other identifiable cause attention turned to zoonotic atypical PNA given animal exposures Empically started on clarithromycin for possible psittacosis + continued on oral fluconazole for possible histoplasmosis Seen in ID clinic 2 weeks post-discharge – both afebrile on outpatient course of macrolide + fluconazole Presumed diagnosis: psittacosis Our Differential Diagnosis “Outbreak” Illnesses MTB Histoplasmosis Leptospirosis with pulmonary hemorrhage Hypersensitivity pneumonitis H1N1 Hantavirus Cryptococcus Atypical Pneumonias Psittacosis Q Fever Legionella Overview Introduction/Epidemiology Microbiology Clinical Features Lab Features Differentiation from other Atypical Pneumonias Diagnostic testing Treatment Prognosis Introduction/Epidemiology AKA Ornithosis or Parrot Fever Birds are major reservoir – any type can be infected Infected birds usually asymptomatic but could be sick Transmission to humans via inhalation of dried feces or respiratory secretions or direct bird contact History of exposure to birds key to raise suspicion Can be sporadic cases or outbreak situations Middle-age adults most commonly affected Children less commonly develop clinical illness Microbiology Chlamydia psittaci Gram negative intracellular bacteria Ability to operate intracellularly allows it to evade host defenses and is rationale for using antibiotics like tetracyclines and macrolides Clinical Features Symptoms develop over weeks after exposure Almost any organ system may be involved Pulmonary symptoms tend to be mild initially Headache typically a prominent feature Other common sx include cough, myalgias, fever Relative bradycardia may be present Disease severity variable - typically mild illness but can cause fulminant sepsis with multiorgan failure Presence/absence of these features neither confirms nor excludes dx Differentiation from other Atypical Pneumonias Atypical PNA account for ~15% of cases of CAP Atypical PNA Pulmonary + Extrapulmonary findings (hepatic/GI, CNS, renal, etc) Zoonotic vs Non-zoonotic infections History key for identifying zoonotic infections – these do not occur randomly…look for an exposure Relative bradycardia classic for Legionella but also may suggest certain zoonotic atypical PNAs Differentiation from other Atypical PNAs Cunha BA, Clin Microbiol Infect 2006;12(S3:12-24) Lab Features Abnormal CXR in up to 80% of patients Lobar consolidation common but no pathognomonic findings CXR findings may be more dramatic than exam findings Liver function test abnormalities common No characteristic hematologic pattern described Diagnostic Testing Serology 4-fold rise in acute and convalescent titers Elevated IgM titer Culture – very difficult to isolate organism Treatment Doxycycline Macrolides (kids, pregnant women) Treat for 10-21 days Contact a vet and treat the birds No need to eliminate birds from the home if they get treated Prognosis Most defervesce within 48 hours after doxycycline Capable of causing severe disease with high mortality if left untreated References Cunha BA. “The Atypical Pneumonias: Clinical Diagnosis and Importance,” Clin Microbiol Infect, 2006;12(S3):1224. Fischer GB, et al. “Histoplasmosis in Children,” Paed Resp Reviews 2009; 10: 172-177. Stewardson AJ. “Psittacosis,” Infect Dis Clin N Am 2010; 24:7-25. Vinetz J, et al. “Chlamydia psittaci,” Hopkins On-Line Abx Guide; www.hopkins-abxguide.org