Épidémiologie des affections rhumatologiques en Afrique subsaharienne

Systemic lupus erythematosus in Native sub-Saharan Africans: A systematic review and meta-analysis

BACKGROUND

The prevalence and phenotype of systemic lupus erythematosus (SLE) have not been thoroughly investigated in Native sub-Saharan Africans despite knowledge that the highest burden of SLE occurs in people with an African trait. Through this systematic review of literature and meta-analysis, we wished to fill this gap.

METHODS

PubMed, EMBASE, Web of Science, African Journals Online, and Global Index Medicus as well as references of retrieved papers were searched to select studies addressing SLE in Native sub-Saharan Africans and published between January 1, 2008 and October 7, 2018. The prevalence of SLE and its characteristics were pooled through narrative review and random-effects model. Heterogeneity (I²) was assessed via the χ² test. Pooled estimates are expressed with 95% confidence intervals. This study is registered with PROSPERO: registration number CRD42019139226.

RESULTS

Out of 1502 papers, 15 hospital-based studies were included. The pooled prevalence of SLE among 28,575 participants was 1.7% (0.8-2.9), with substantial heterogeneity between studies (I² = 96.9% [94.8%; 98.1%], τ2 = 0.0020, p < 0.0001). The mean age at diagnosis ranged from 28.8 to 39.2 years. The female proportion varied from 88% to 100%. Rheumatological (5.1%-99.9%), dermatological (4.3%-100%) and hematological (1.4-86.9%) manifestations were the commonest clinical features of SLE. Patients had a high seroprevalence for anti-ribonucleoprotein 57.9% (36.4-77.9), anti-Smith 53.5% (40.4-66.2), anti-Sjogren syndrome antigen A 45.6% (19.2-73.4) and anti-Sjogren syndrome antigen B 33.7% (13.6-57.6) autoantibodies. The most used treatments were corticosteroids 99% (94.9-100) and antimalarials 62. 8% (23.3-94.1). The pooled mortality rate was 10.3% (3.3-20.6) and death was mainly due to infections, kidney disease and neurological involvement.

CONCLUSION

Over the last 30 years, SLE was not rare among Native sub-Saharan Africans and its featured characteristics were earlier onset, female predominance, and high seropositivity for extractable nuclear antigen autoantibodies. Corticosteroids and antimalarials were the standard treatments. The mortality rate was high. Population prevalence and incidence as well as full description of SLE characteristics in Native sub-Saharan Africans are needed.

Hyper-Uricemia and Gouty Access in the Adult Population of the Southeast of Gabon: Biochemical Aspects

Gout is caused by a chronic hyperuricemia whose complications are not currently well evaluated in Africa. The aim of this study was to determine the prevalence and risk factors of hyperuricemia and gout in 85 patients recruited. A total of 26 cases of hyperuricemia, i.e., 30.6% of the study population, with 12 cases of gout and seven cases of gouty access. In this population, hyperuricemia was proportional to age (p-value < 10^-4, OR = 2.6), but it was more prevalent in men, 23.5% versus 7.1% for women (p-value = 0.0047). In addition, none of these women showed signs of a gouty affection. Consumption of alcohol (OR = 13) and nucleoprotein-rich foods, obesity (BMI 30 kg/m²; OR = 6), family history of gout (OR = 6.8), as well as diseases such as high blood pressure (associated with taking diuretics; OR = 1.7), renal insufficiency (OR = 4.4) and diabetes (p < 0.049) were the main factors of the diseases associated with gout and hyperuricemia in this population. The biochemical role of these factors may increase and/or decrease the processes of synthesis and/or elimination of uric acid by acting on metabolites involved in the regulation of urate production.

Is inflammatory joint disease in HIV-infected patients a form of spondyloarthropathy?

In Congo-Brazzaville, the seroprevalence of HIV infection is in the range 7-8%, and AIDS is the leading cause of aseptic arthritis (60% of cases).

PATIENTS, MATERIAL AND METHODS

The ESSG and Amor's criteria for spondyloarthropathy were evaluated in 83 patients with HIV infection admitted for aseptic arthritis to the rheumatology department of the Brazzaville teaching hospital, over an 8-year period.

RESULTS

All 83 patients were CDC stage IV; 66 (80%) had polyarthritis and 17 (20%) oligoarthritis. A single patient met ESSG and Amor's criteria, with six points; one patient had five points and 15 had three points. The joint involvement was asymmetrical and nonerosive. Nonsteroidal antiinflammatory therapy ensured resolution of the manifestations within 4-8 weeks. The most common sites of involvement were the knees (84%), ankles (59%), and great toes (23%) at the lower limbs and the wrists (41%), elbows (29%), and metacarpophalangeal and interphalangeal joints (25%) at the upper limbs.

CONCLUSION

Inflammatory arthritis in HIV patients does not meet ESSG or Amor's criteria for spondyloarthropathy.