Clinical and laboratory features of brucellosis in a university hospital in Tunisia

The increase in the number of brucellosis cases between 2014 and 2017 (14 and 90 cases respectively) led us to study the biological and clinical-epidemiologic characteristics patients hospitalized in Rabta hospital of Tunis.

This retrospective study was conducted in Rabta Hospital in Tunis between 2016 and 2017. It includes 131 patients who had a positive bacteriological diagnosis of Brucella between 2016 and 2017. Diagnosis of brucellosis was made in blood culture by using Bactalert (Biomerieux®). Identification of Brucella was realized by Gram staining, catalase, oxydase. Serological diagnosis was made by testing sera for brucellosis agglutinins with Rose Bengale and the standard agglutination test. The collected data were analyzed by SPSS softcare version 24.

The prevalence of Brucellosis in Rabta hospital increases from 14 cases in 2014 to 90 cases in 2017. The mean age was 45 years and ages range from 16 to 84 years. Rural origin was found in 75 cases (68%). Ninety-seven patients (89%) were hospitalized in the infectious diseases department. The average length of hospitalization was 17.25 days. Fifty-seven patients (52%) had a history of consuming unpasteurized dairy products and 45 (41%) were farmers. Fever was the predominant symptom in 104 cases (95%). Osteoarticular involvement is the most common complication of brucellosis and it occurred in 28% of patients. Blood cultures were 73 cases and 42 (57%) were positive for Brucella spp. Rose Bengale was positive in 100% of cases. High titles of the standard agglutination test (superior to 1/1280) were noted in 24 cases (22%).

Brucellosis is still endemic In Tunisia. Contact with domestic animals and consumption of raw milk and milk products seems to be the major mode of transmission. Control of animal infection by vaccination, occupational and personal hygiene, farm sanitation and preventive measures can reduce disease incidence.