[Etiology of oligoarthritis in equatorial Africa. A retrospective study of 80 cases in Brazzaville, Congo].

Purpose: The objective was to determine causes of oligoarthritis in patients hospitalized in a Central Africa teaching hospital.

Methods: We collected case reports of patients presenting with arthritis located in two or three joints. Analysis included the disease frequency, age, gender, and etiology. Etiology was defined according to common criteria used for the diagnosis of rheumatic diseases.

Results: Eighty patients (60 males and 20 females; age range: 7-80 years; mean age: 35.6 years) were included in the study. Altogether they represented 5.8% of in-patients and 14.3% of the patients suffering from arthritis. The following causes were observed: HIV-related arthritis, 21 cases (12 males and nine females; mean age: 32.2 years). Arthritis was asymmetrical, acute and non-erosive. Recovery was observed after administration of a non steroidal anti-inflammatory drug for 4-6-weeks. Gout: 17 patients (15 males and two females; mean age: 51.1 years). Gout was related with one or more of the following: alcoholism (16 cases), hypertension (nine cases), and obesity (three cases), and was chronic in 12 patients. Infection-related arthritis: 17 cases (five males and 12 females; mean age 25.3 years). Portal of entry was either cutaneous (five cases) or obstetrical (seven cases). Most of the time, the causative microorganism was Staphylococcus. Rheumatic fever: five patients (four males and one female; mean age 18 years). Juvenile chronic arthritis: three cases (one male and two females; mean age 12.6 years). Reactive arthritis: three cases (three males; mean age: 32). Etiology is still unknown for 14 cases.

Conclusion: Oligoarthritis appears to be secondary to HIV or bacterial infection in young adults, while gout affects more often the elderly. This study confirms that spondylarthropathy is unusual in Sub-Saharan Africa. Furthermore, it emphasizes the existence of numerous cases in whom etiology of the diseases is unknown.