Characteristics of Intestinal Volvulus and Risk of Mortality in Malawi.

backgroundIntestinal volvulus is a common cause of mechanical intestinal obstruction (MIO) in Africa. Sigmoid volvulus has been well characterized in both high-income and low-income countries, but there is also a predilection for small bowel volvulus in sub-Saharan Africa.

methodsAn analysis was performed of the Kamuzu Central Hospital Acute Care Surgery Registry from 2013 to 2019 on patients presenting with intestinal volvulus. Bivariate analysis was performed for covariates based on the intestinal volvulus type. Multivariate Poisson regression models estimated the relative risk of volvulus and mortality.

resultsA total of 4352 patients were captured in the registry. Overall, 1037 patients (23.8%) were diagnosed with MIO. Intestinal volvulus accounted for 499 (48.1%) of patients with MIO. Sigmoid volvulus, midgut volvulus, ileosigmoid knotting, and cecal volvulus accounted for 57.7% (n = 288), 19.8% (n = 99), 20.8% (n = 104), and 1.6% (n = 8), respectively. Mean age was 46.8 years (SD 17.2) with a male preponderance (n = 429, 86.0%) and 14.8% (n = 74) mortality. Overall, the most common operations performed were large bowel (n = 326, 74.4%) and small bowel (n = 76, 16.7%) resections with 18.0% (n = 90) ostomy formation. Upon regression modeling, the relative risk for volvulus was 2.7 times higher in men than women after controlling for season and age. There was no statistically significant difference in the relative risk of mortality based on the type of volvulus.

conclusionVolvulus is a significant cause of primary bowel obstruction in sub-Saharan Africa. Type of intestinal volvulus is not associated increased risk of mortality. Reasons for increases in the incidence of small bowel volvulus are still largely undetermined.