BACKGROUND Rhodococcus equi (formerly Corynebacterium) has been long considered an exclusively zoopathogenic microbe causing mainly granulomatous pneumonias and lung abscesses in young foals. The aim of this paper was to analyse substantial features of R, equi infections hitherto reported in man. METHODS AND RESULTS MEDLINE database was searched for relevant reports. When the original source was not obtained the data from reviews were employed. Together, 105 cases of R, equi infection in man were reported. Median age was 35 years with a range from 9 months to 83 years. The male: female ratio was 3.3. Lungs were involved in 72 cases (69%), extrapulmonary abscesses as the only symptom of infection were described in 9 cases, septic state in 7 cases. Clinical outcome was known in 98 cases, being fatal in 41 (42%). Therapy was mentioned in 70 reports, the most often used drugs being erythromycin (30 cases, 12 deaths), rifampicin (19 cases, 7 deaths) and vancomycin (18 cases, 6 deaths). R. equi was isolated from the sputum of 69% patients with the pulmonary involvement. Blood cultures were positive in 35% of cases. Out of total, 49% persons were HIV positive. Median age for HIV positive patients was 32 years with a range from 18 to 71 years, for HIV negative patients 52 years with a range from 9 months to 83 years. There were 97% males in the HIV positive group in contrast to 59% in the HIV negative group (p < 0.01). Lungs were involved in 90% of HIV positive and 48% of HIV negative cases (p < 0.01). Extrapulmonary abscesses as the only sign of infection were seen in 2% of HIV positive persons and in 15% of HIV negative ones (p < 0.05). Outcome was fatal for 60% of the HIV positive hosts and for 28% of the HIV negative individuals (p < 0.01). R. equi was isolated from the sputum of 80% pneumonic HIV positive patients and of 50% of pneumonic patients without HIV infection (p < 0.05). R. equi was detected in the blood of 67% of HIV positive patients and of 33% of HIV negative ones (p < 0.01). CONCLUSIONS The analysis of published reports shows that whereas R. equi causes mainly pneumonia in persons with HIV infection, in HIV negative individuals extrapulmonary manifestations slightly prevail, most often abscesses, sepsis, eye involvement and wound infections.