It is unclear whether bacterial colonization in hidradenitis suppurativa/acne inversa (HS) comprises a primary cause, triggering factor or secondary phenomenon of the disease pathogenesis. Furthermore, the connection between certain bacterial species, the disease severity and its localization is unknown. Bacterial species were isolated from HS lesions to reveal a potential correlation with localization and disease severity. Ninety swab tests were prospectively obtained from 90 HS lesions of 50 consecutive patients. The material was cultured under aerobic and anaerobic conditions. The identified species were statistically correlated with Hurley stage and localization of the lesions. The most prevalent isolates were reported. Hurley stage significantly correlated with disease localization. Particular bacterial species were associated with "extended" disease and Hurley III stage with the detection of both aerobic and anaerobic bacteria and with a higher number of species. The presence of bacterial species is dependent on the local milieu, which correlates with the localization of the disease, its clinical manifestations and its extension.