1
|
Archampong TN, Asmah RH, Richards CJ, Martin VJ, Bayliss CD, Botão E, David L, Beleza S, Carrilho C. Gastro-duodenal disease in Africa: Literature review and clinical data from Accra, Ghana. World J Gastroenterol 2019; 25:3344-3358. [PMID: 31341360 PMCID: PMC6639557 DOI: 10.3748/wjg.v25.i26.3344] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2019] [Revised: 05/14/2019] [Accepted: 05/31/2019] [Indexed: 02/06/2023] Open
Abstract
Gastroduodenal disease (GDD) was initially thought to be uncommon in Africa. Amongst others, lack of access to optimal health infrastructure and suspicion of conventional medicine resulted in the reported prevalence of GDD being significantly lower than that in other areas of the world. Following the increasing availability of flexible upper gastro-intestinal endoscopy, it has now become apparent that GDD, especially peptic ulcer disease (PUD), is prevalent across the continent of Africa. Recognised risk factors for gastric cancer (GCA) include Helicobater pylori (H. pylori), diet, Epstein-Barr virus infection and industrial chemical exposure, while those for PUD are H. pylori, non-steroidal anti-inflammatory drug (NSAID)-use, smoking and alcohol consumption. Of these, H. pylori is generally accepted to be causally related to the development of atrophic gastritis (AG), intestinal metaplasia (IM), PUD and distal GCA. Here, we perform a systematic review of the patterns of GDD across Africa obtained with endoscopy, and complement the analysis with new data obtained on pre-malignant gastric his-topathological lesions in Accra, Ghana which was compared with previous data from Maputo, Mozambique. As there is a general lack of structured cohort studies in Africa, we also considered endoscopy-based hospital or tertiary centre studies of symptomatic individuals. In Africa, there is considerable heterogeneity in the prevalence of PUD with no clear geographical patterns. Furthermore, there are differences in PUD within-country despite universally endemic H. pylori infection. PUD is not uncommon in Africa. Most of the African tertiary-centre studies had higher prevalence of PUD when compared with similar studies in western countries. An additional intriguing observation is a recent, ongoing decline in PUD in some African countries where H. pylori infection is still high. One possible reason for the high, sustained prevalence of PUD may be the significant use of NSAIDs in local or over-the-counter preparations. The prevalence of AG and IM, were similar or modestly higher over rates in western countries but lower than those seen in Asia. . In our new data, sampling of 136 patients in Accra detected evidence of pre-malignant lesions (AG and/or IM) in 20 individuals (14.7%). Likewise, the prevalence of pre-malignant lesions, in a sample of 109 patients from Maputo, were 8.3% AG and 8.3% IM. While H. pylori is endemic in Africa, the observed prevalence for GCA is rather low. However, cancer data is drawn from country cancer registries that are not comprehensive due to considerable variation in the availability of efficient local cancer reporting systems, diagnostic health facilities and expertise. Validation of cases and their source as well as specificity of outcome definitions are not explicit in most studies further contributing to uncertainty about the precise incidence rates of GCA on the continent. We conclude that evidence is still lacking to support (or not) the African enigma theory due to inconsistencies in the data that indicate a particularly low incidence of GDD in African countries.
Collapse
Affiliation(s)
- Timothy N Archampong
- Department of Medicine and Therapeutics, School of Medicine and Dentistry, University of Ghana, Accra Box 4236, Ghana
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, United Kingdom
| | - Richard H Asmah
- Department of Medical Laboratory Sciences, School of Biomedical and Allied Health Sciences, University of Ghana, Accra Box 4236, Ghana
| | - Cathy J Richards
- Department of Histopathology, Leicester Royal Infirmary, Leicester LE1 5WW, United Kingdom
| | - Vicki J Martin
- Department of Histopathology, Leicester Royal Infirmary, Leicester LE1 5WW, United Kingdom
| | - Christopher D Bayliss
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, United Kingdom
| | - Edília Botão
- Department of Pathology, Maputo Central Hospital, Maputo POBox 1164, Mozambique
| | - Leonor David
- Department of Pathology, Medical Faculty of the University of Porto, Porto 4200-465, Portugal
- Institute of Molecular Pathology and Immunology at the University of Porto (Ipatimup), Porto 4200-465, Portugal
- Instituto de Investigação e Inovação em Saúde (i3S), University of Porto, Porto 4200-465, Portugal
| | - Sandra Beleza
- Department of Genetics and Genome Biology, University of Leicester, Leicester LE1 7RH, United Kingdom
| | - Carla Carrilho
- Department of Pathology, Faculty of Medicine, Eduardo Mondlane University, Maputo POBox 257, Mozambique
- Department of Pathology, Maputo Central Hospital, Maputo POBox 1164, Mozambique
| |
Collapse
|