Inflammatory bowel disease in sub-Saharan Africa: epidemiology, risk factors, and challenges in diagnosis.

Over the past century, the incidence of inflammatory bowel disease (IBD) in high-income countries has shown a sharp rise that then plateaued, and a similar trend has been observed in newly industrialised countries. IBD has long been considered uncommon in sub-Saharan Africa, possibly reflecting low exposure to environmental risk factors described in high-income populations. Alternatively, individuals living in sub-Saharan Africa might have a different genetic disposition. However, some cases of IBD might remain undetected in sub-Saharan Africa because of a lack of awareness, deficiencies in diagnostic and clinical capacity, and a substantial rate of misdiagnosis due to the high burden of infectious diseases. There are few published data describing the natural history of IBD in sub-Saharan Africa, and the true burden of the disease remains largely unknown, although there is some evidence that the incidence of IBD is rising in this region. This Series paper summarises the present understanding of IBD and challenges facing clinicians when diagnosing this disease in sub-Saharan Africa.