Source: may never be identified due to the ubiquitous nature of the organism
Route of infection: inhalation, across the olfactory epithelium in the nose, possibly inoculation
Time course: may fulminant, acute or chronic
Patients at risk:
(1) AIDS with depressed CD4-positive lymphocytes
(2) severe immunosuppression
Clinical findings - involvement of 2 or more organs:
(1) pneumonia
(2) sinusitis or rhinits
(3) meningoencephalitis
(4) hepatitis
(5) nephritis
(6) tracheitis
(7) adrenals
(8) osteomyelitis
(9) skin nodules and/or ulcers
(10) otitis
(11) muscle abscess
Diagnosis - demonstration of trophozoites or cysts:
(1) brain biopsy
(2) examination of CSF
(3) culture (NNA seeded with E. coli, supplemented PYG, mammalian cell culture)
(4) indirect immunofluorescence
(5) PCR
