Trends in the publication of infantile hypertrophic pyloric stenosis in Africa: A systematic review

Abstract
There are still global variations in the epidemiology of infantile hypertrophic pyloric stenosis, although the clinical presentations may be similar. Outcome of management, however, may depend on the degree of evolution of management of the anomaly. This review aimed at evaluating the trends of reporting of infantile hypertrophic pyloric stenosis from Africa. An evaluation of all publications from Africa on infantile hypertrophic pyloric stenosis focusing on epidemiology, evolution of management of the anomaly was carried out. Literature search of all publications from Africa on Infantile hypertrophic pyloric stenosis was conducted from January 1, 1951, to December 31, 2018. The articles were sourced from the databases of African Index Medicus, OvidSP, PubMed, African Journal Online, and Google Scholar. Extracted from these publications were information on the type of article, trend of reporting, the country of publication, demographic details of the patients, number of cases, clinical presentation, pre-operative management, type of surgical approach, and the outcome of management. Overall, 40 articles were published from 11 countries. Of these, 16 (40.0%) were published in the first 35 years (Group A, 1951–1985) and 24 (60.0%) published in the later 33 years (Group B, 1986– 2018). Case reports 8 (20.0%) and case series 5 (12.5%) were predominant in Group A, whereas retrospective studies 12 (30.0%) predominated in Group B. The countries of publication included Nigeria (27.5%), South Africa (15.0%), Egypt (12.5%), Tanzania (10.0%), and Zimbabwe (10.0%). A total of 811 patients diagnosed and managed for infantile hypertrophic pyloric stenosis (IHPS) were reported. Their ages ranged from 1 day to 1 year with an incidence that ranged from 1 in 550 to 12.9 in 1000. There were 621 boys and 114 girls (M:F – 5.5:1). All the patients were breastfed with an average birth rank incidence of 42.4% among firstborns, 19.5% in second borns, 15.2% in third borns, 13.2% among fourth borns, and 10.0% among fifth borns and beyond. Associated congenital anomalies were reported in 5 (12.5%) studies with an incidence of 6.9–20% occurring in a total of 28 patients. All but 3 (7.5%) studies reported that open surgery was adopted to perform Ramstedt’s pyloromyotomy on the patients. Reported post-operative complications include mucosal perforation in 8 (20.0%) studies, surgical site infection in 7 (17.5%), gastroduodenal tear 2 (5.0%), and hemorrhage and incisional hernia in 1 (2.5%) study each. Mortality was reported in 26 (65.0%) studies with a range of 1.8–50% and a mean mortality rate of 5.2%. There has been a change in the trend of reporting IHPS in Africa over the years, with increasing comparative studies on the modalities of management compared to case reports and series. Still very limited work has been done in the aspect of genetics and etiology of IHPS among Africans. There is a need to increase funding in this regard and to encourage multi-center collaborations in the study of this relatively rare condition.