0521779407-B01 CUNY1086/Karliner 0 521 77940 7 June 4, 2007 20:52
244 Blastomyces Dermatitidis■Acute infection:
➣Acute pulmonary infection often unrecognized
➣1/2 develop symptomatic disease, incubation 30–45 d
➣Nonspecific symptoms, mimic influenza
■Chronic/recurrent infection – most common course:
➣Pulmonary: chronic pneumonia, productive cough, hemoptysis,
weight loss, pleuritic chest pain
➣Skin: most common extrapulmonary manifestation (40–80%
cases), verrucous lesions (similar to squamous cell ca) or
ulcerative-type; occur mucosa of nose/mouth/larynx
➣Subcutaneous nodules: cold abscesses in conjunction with pulm
and other extrapulm disease, often with acutely ill patient
➣Bone/Joint: long bones, vertebrae, ribs most common with well-
circumscribed osteolytic lesion
➣Genitourinary tract: 10–30% of cases in men, prostate and epi-
didymis
➣CNS: Uncommon in normal host (<5% cases)
➣AIDS: more common complications, usually as abscess or
meningitistests
Laboratory
■Microbiology – culture
➣Standard fungal media
■Serology
➣Serum comp fix neither specific nor sensitive, as are the other
antibody-dependent modalities
■Skin testing
➣No reagent currently available
■Histopathology
➣Direct examination of sputum/pus/secretions with or without
KOH, bronchoscopy only for patients not producing sputum
➣Pyogranuloma on tissue section (GMS stain)Imaging
■CXR
➣Acute pulmonary: nonspecific, lobar or segmented consolida-
tion
➣Chronic pulmonary: lobar or segmental infiltrates, with or with-
out cavitation; intermediate-sized nodules, solitary cavities,
fibronodular infiltrates