Spondyloarthritis in Sub-Saharan Africa

Abstract

Spondyloarthritis (SpA) is generally uncommon in sub-Saharan Africa, in part because of the rarity of HLA-B27 in this region. However, the relationship between HLA-B27 and SpA, particularly ankylosing spondylitis (AS), is complex. Despite the HLA-B 27:05 risk allele occurring in some West African populations, associated AS is not seen. In fact, most patients with AS are HLA-B27-negative, although there is emerging evidence that another class I HLA molecule, HLA-B 14:03, is associated with AS in black Africans. The Assessment of SpondyloArthritis International Society criteria for detecting early axial disease are of limited value in sub-Saharan Africa, because of both the rarity of HLA-B27 and very limited access to magnetic resonance imaging. Reactive arthritis (ReA), psoriatic arthritis, and undifferentiated SpA are seen mainly in the context of HIV infection, although the exact effect of the virus in the pathogenesis of arthritis is unclear. In Zambia, ReA is associated with the HLA-B*57:03 allele, which is paradoxically also associated with slow progression of HIV infection. HIV-associated ReA has a more protracted and aggressive course than standard ReA. Enthesitis-related arthritis is more common in children infected with HIV by vertical mother-to child transmission. Use of TNF inhibitors for axial disease is problematic, mainly because of cost, but also because of potential safety problems, especially reactivation of tuberculosis.

Spondyloarthritis in African Blacks

“…This was first noted in a cross-sectional survey of 1352 South African blacks in a study in 1975 5 . In more recent reviews of the subject, similar findings were found from other parts of Africa 6,7 .…”

Ankylosing Spondylitis in Sub-Saharan Africa: A Series of 48 Cases Reported in Burkina Faso (West Africa)

“…The clinical presentation of the disease is similar to that of the Caucasian subject [5]; however, extra-articular manifestations seem rare [10]. There was no statistically significant difference by gender.…”

“…The rarity of AS in sub-Saharan Africa seems to be related to the scarcity of HLA B27 antigen. HLA-B 14:03 is evoked as possibly associated with the black African SA [5]. Indeed, this allele was found in 4 among the 8 SA patients seen in Togo and among any control and in 2 of the 3 SA patients seen in Zambia [2] [9].…”

“…Ankylosing spondylitis does not seem so rare in Burkina Faso, unlike some neighboring countries (Côte d'Ivoire, Togo, Benin); unpublished series are reported in Mali and Niger, mainland countries like Burkina Faso with common ethnic groups. The clinical feature of AS in black African patients seems to be the rarity of extra-articular manifestations [5].…”

Poncet’s disease in human immunodeficiency virus: a case report

“…HLA B 27 studies were however not done in our patient. Studies in African patients document absence of HLA B27, and possible HLA B14 association to reactive arthritis [17]. …”