Background & objectives:Brucellosis can lead to haematological abnormalities including cytopenia confusing with haematological malignancies. The aim of this study was to compare the main characteristics of brucellosis patients without cytopenia (Group 1) and with cytopenia (Group 2).Methods:This five-year period study which was performed in two referral hospitals in Turkey, included all adult brucellosis patients. Abnormally, low counts of leucocyte or haemoglobin or platelets in a patient were considered as cytopenia. The demographics, clinical, laboratory, treatment and outcome data were analyzed.Results:A total of 484 brucellosis patients were enrolled. Among the cases, 162 (33.5%) of them had cytopenia. One hundred and four (21.5%) had anaemia, 88 (18.8%) had thrombocytopenia, 71 (14.6%) had leucopenia and 28 (5.8%) had pancytopenia. The mean age of group 2 was 35.01±16.05 yr and it was 33.31±14.39 yr in group 1. While there was no difference between the groups in terms of duration of treatment, the median length of hospital stay (LOS) was significantly longer in group 2 (9 vs 10 days; P <0.001). The most frequently applied combination therapy consisted of doxycycline plus rifampicin and doxycycline plus streptomycin regimens. No significant difference was observed in terms of duration of treatment, LOS and restoration time of cytopenia between the patients who received either of these combinations.Interpretation & conclusions:Our findings suggested that the patients with cytopenia should be investigated for brucellosis, especially if living in, or with a history of travel to, endemic areas, in view of the increase in world travel.