Internal Medicine

0521779407-17 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 21:19

Psittacosis 1235

Signs & Symptoms

■Pneumonia most common presentation, with fevers, chills, severe

headache, myalgias and a nonproductive cough; the typhoidal

presentation includes systemic symptoms listed above and rela-

tive bradycardia, hepatosplenomegally, Horder’s spots (erythema-

tous, blanching, maculopapular rash) without respiratory sym-

ptoms.

tests

■Routine laboratory tests often abnormal, but non-diagnostic; WBC

may be low, normal or high; liver function tests mildly abnormal

in 50%; lobar consolidation most commonly seen on CXR (75%),

although other patterns described (may have extensive infiltrates

with only minimal findings on exam); sputum shows numerous poly-

morphonuclear leukocytes and no organisms

■Definitive diagnosis made serologically (fourfold or greater rise in

titer confirms diagnosis; a single titer of 1:32 or higher in a patient

with a compatible disease is a probable case)

differential diagnosis

■Symptoms nonspecific and thus differential extensive; atypical

pneumonia due to mycoplasma,C. pneumoniae, legionella, viruses;

typhoidal presentation suggests typhoid fever, bacteremia, endo-

carditis, viral illness, mononucleosis; hepatitis suggests viral causes,

brucella, Q fever, toxoplasmosis

management

■Careful epidemiologic history critical in making diagnosis

■Routine supportive care

specific therapy

■Doxycycline or tetracycline for 2–3 weeks: drugs of choice

■Erythromycin an alternative, but may be less effective

follow-up

■Clinical response very rapid with improvement in 1–2 days

■CXR abnormalities slow to resolve (6–20 weeks)

complications and prognosis

■Rare complications include cardiac involvement (myocarditis, peri-

carditis, culture-negative endocarditis) and neurologic disease

(meningitis, encephalitis)

■With therapy the mortality rate is 1%.