Internal Medicine

0521779407-15 CUNY1086/Karliner 0 521 77940 7 June 7, 2007 18:43

1052 Nocardiosis

■Definitive diagnosis made by culturing organism from sputum, aspi-

rate of lung nodule, lung abscess, brain abscess or cutaneous lesion

■Although Nocardia spp grow on most routine media, the laboratory

should be notified to look for the organism since it can take 3–5 days

to grow and colonies may be difficult to detect if mixed with other

respiratory flora.

PCR not yet widely clinically available

differential diagnosis

■Other causes of pneumonia – in the immunocompromised patient

Cryptococcus neoformans, Aspergillus spp, other fungi,M. tubercu-

losis, atypical mycobacteria, aspiration, other bacteria; other causes

of brain abscess – bacterial and fungal; cutaneous lesions – fungal

and mycobacterial

management

■Nocardiosis should be considered in any immunocompromised

patient with pulmonary, cutaneous and/or CNS disease.

specific therapy

■Sensitivities of various species of Nocardia vary (N. farcinicais most

resistant) and sensitivity testing should be performed on all clinical

isolates.

■Trimethoprim-sulfamethoxazole (TMP-SMX) at a dose of TMP 5–10

mg/kg per day, in 2 or 3 divided doses, is the drug of choice

with the most clinical experience; alternatives include imipenem,

third-generation cephalosporins (cefotaxime and ceftriaxone), ami-

kacin, amoxicillin-clavulanate, minocycline and fluoroquinolones

(ciprofloxacin and levofloxacin)

■Combination therapy with TMP-SMX and amikacin or imipenem

or a third-generation cephalosporin has been advocated as initial

therapy for patients who are immunocompromised with systemic

disease

■Duration of therapy depends on site of infection and the immune

status of the host; cutaneous disease treated for 1–3 months; in the

non-immunosuppressed patient, pulmonary and non-CNS dissem-

inated disease treated for at least 6 months and CNS disease treated

at least 12 months; immunocompromised patients treated at least

12 months

■Immunosuppressive medications should be decreased or discontin-

ued, if possible