Fecal Occult Blood and Fecal Calprotectin as Point-of-Care Markers of Intestinal Morbidity in Ugandan Children with Schistosoma mansoni Infection

Abstract

BackgroundCalprotectin is a calcium-binding cytoplasmic protein found in neutrophils and increasingly used as a marker of bowel inflammation. Fecal occult blood (FOB) is also a dependable indicator of bowel morbidity. The objective of our study was to determine the applicability of these tests as surrogate markers of Schistosoma mansoni intestinal morbidity before and after treatment with praziquantel (PZQ).Methods216 children (ages 3–9 years old) from Buliisa District in Lake Albert, Uganda were examined and treated with PZQ at baseline in October 2012 with 211 of them re-examined 24 days later for S. mansoni and other soil transmitted helminths (STH). POC calprotectin and FOB assays were performed at both time points on a subset of children. Associations between the test results and infection were analysed by logistic regression.ResultsFecal calprotectin concentrations of 150–300 µg/g were associated with S. mansoni egg patent infection both at baseline and follow up (OR: 12.5 P = 0.05; OR: 6.8 P = 0.02). FOB had a very strong association with baseline anemia (OR: 9.2 P = 0.03) and medium and high egg intensity schistosomiasis at follow up (OR: 6.6 P = 0.03; OR: 51.3 P = 0.003). Both tests were strongly associated with heavy intensity S. mansoni infections. There was a significant decrease in FOB and calprotectin test positivity after PZQ treatment in those children who had egg patent schistosomiasis at baseline.ConclusionsBoth FOB and calprotectin rapid assays were found to correlate positively and strongly with egg patent S. mansoni infection with a positive ameloriation response after PZQ treatment indicative of short term reversion of morbidity. Both tests were appropriate for use in the field with excellent operational performance and reliability. Due to its lower-cost which makes its scale-up of use affordable, FOB could be immediately adopted as a monitoring tool for PC campaigns for efficacy evaluation before and after treatment.

An extensive burden of giardiasis associated with intestinal schistosomiasis and anaemia in school children on the shoreline of Lake Albert, Uganda

“…Triple infections of intestinal schistosomaisis, giardiasis and malaria affected just under a fifth of all sampled children. Although all were sufficiently fit to attend school, more general markers of ill-health, such as anaemia (25.7%) and faecal occult blood (11.0%), revealed an underlying morbidity, as previously seen in this area 31,32 . Along the lakeshore, access to tap water is still very poor which no doubt helps both intestinal schistosomiasis and giardiasis flourish 17,[33][34][35] .…”

New diagnostic tools in schistosomiasis

“…Although quantification of haematuria reliably indicates morbidity due to urogenital schistosomiasis, the identification of simple, fieldapplicable proxy markers for intestinal schistosomiasis is more challenging. Recently, two faecal POC assays have been shown to be strongly associated with heavy S. mansoni infection, namely (a) faecal occult blood tests and (b) faecal calprotectin (a calcium-binding protein of human neutrophils) [110]. It follows that these markers may be used to reveal bowel morbidity caused by intestinal schistosomiasis.…”

High burden of Schistosoma mansoni infection in school-aged children in Marolambo District, Madagascar

“…Schistosoma mansoni in particular results in intestinal and hepatosplenic disease causing abdominal pain, blood in stool, reduced appetite and diarrhoea [12, 13]. In chronic disease states, hepatic fibrosis can develop 5–15 years after initial infection, though earlier cases have been documented in preschool children [14, 15].…”