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BACKGROUND: Schistosoma mansoni related hepatic fibrosis is usually associated with hemodynamic alteration with increased mortality due to bleeding varices. The diagnosis of varices before bleeding imposes a big challenge in resource-limited countries using endoscopy. Published evidence on the utility of non-invasive clinical tools in predicting the presence of varices among patients with S. mansoni related periportal fibrosis is still inadequate including Aspartate to platelet ratio index (APRI) and Platelet to splenic diameter ratio (PSDR) levels. This study describes the determinants of portal varices and assesses the potential utility of the APRI and PSDR level in the discrimination of portal varices among patients with S. mansoni related periportal fibrosis (PPF). METHODS: A case-control study using cross-sectional data was done among patients with Schistosoma mansoni related periportal fibrosis at Bugando Medical Centre, in Mwanza Tanzania. The derivation cohort included patients enrolled between 2015 and 2019 and the validation cohort included patients enrolled from 2019 till March 2021. Socio-demographic, laboratory, ultrasound, and upper digestive endoscopic information were analyzed using STATA 13. The prevalence and determinants of varices were determined by logistic regression. The sensitivity and specificity of independent factors were determined to assess their utility in discriminating the presence of portal varices in patients with PPF. RESULTS: In total, 250 patients were included in the derivation cohort, 109 (43.6%; 95% CI 37.3-49.9) of them had varices. The odds of having varices were independently increased among patients with higher APRI levels than 1.51, (AOR: 5.8; 95% CI 3.1-11.1; p < 0.001) and PSDR levels that were lower than 5700 (AOR: 5.9; 95% CI 3.2-11.2; p < 0.001). Both APRI and PSDR levels had significantly high sensitivity and specificity in predicting the presence of esophageal varices. However, the combined values of APRI and PSDR had higher specificity than any of the two markers. Of the 200 patients in the validation cohort 94 (47.0%; 95% CI 40.0-54.2) had varices, the discriminative power of the final model and the predictive ability of both APRI, PSDR, and APRI-PSDR combined levels were highly maintained. CONCLUSIONS: This study indicates that varices are a common encounter among patients with S. mansoni related periportal fibrosis and it is independently associated with higher APRI and lower PSDR levels suggesting that these tools are potential discriminators of varices in this subgroup of patients. The reproducibility of these results should further be assessed longitudinally as potential non-invasive tools in selecting patients at high risk of having esophageal varices who could benefit from the targeted endoscopic intervention in a resource-limited setting like ours.

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BACKGROUND: Schistosoma mansoni is highly endemic in the Lake Zone part of Tanzania and most people are chronically infected. Periportal fibrosis (PPF) is the commonest complication of chronic S. mansoni infection documented in up to 42% of studied participants in the community-based studies. These patients are at high risk of mortality since most of them are diagnosed late with bleeding varices. At Bugando, Schistosoma-related varices contributed to 70% of patients admitted due to vomiting blood with a two months' mortality of over 10%. Earlier studies had reported higher mortality of up to 29% among patients with PPF even with the best in-hospital care. Understanding factors that increased the risk of mortality is important clinically in devising ways that can improve the outcome of this subgroup of patients. METHODS: A retrospective analysis of patients with PPF from 2015 through 2018 was done. Their sociodemographic, clinical, laboratory, ultrasonographic, endoscopic, and survival status data were collected for analysis. STATA 13 was used for analysis, the prevalence of varices, active schistosomiasis, and hepatitis B coinfection was determined. Cumulative mortality as a major outcome was also determined, and factors associated with increased risk of mortality were assessed by a logistic regression model. RESULTS: In total, 250 participants were included in this analysis. Majority, 222 (88.8%; 95% CI: 84.2-92.4) had active S. mansoni infection, and 40 (16.0%; 95% CI: 11.6-21.1) had S. mansoni-HBV coinfection. Cumulatively, 39 (15.6%; 95% CI: 11.3-20.7) patients died, with most deaths, 31 (79.5%; 95% CI: 63.5-90.7) occurring within two years following the diagnosis of PPF (chi2 = 6.3; p = 0.012). The odds of mortality were independently associated with fishing (OR: 10.8; 95% CI: 2.2-52; p = 0.003), upper gastro intestinal bleeding (OR: 2.4; 95% CI: 1.1-5.4; p = 0.037), HBV coinfection (OR: 3.3; 95% CI: 1.2-91; p = 0.019), and ascites (OR: 3.3; 95% CI: 1.3-8.2; p = 0.010). CONCLUSIONS: In this, S. mansoni endemic area, varices, actives schistosomiasis, hepatitis B coinfection, and mortality are highly common. Screening for varices and initiation of prophylaxis, administration of praziquantel, and screening for hepatitis B should be part and parcel of care of these patients. The first two years of diagnosis, patients are at high risk of mortality; risk factors in this study should assist planning a closer follow-up of patients at risk of mortality to improve their long-term outcome.