Level of fecal neopterin and calprotectin in asymptomatic and symptomatic norovirus-infected children with malnutrition in Indonesia

Abstract

Background

Norovirus infection is the second most frequent viral agent causing gastroenteritis worldwide. Asymptomatic norovirus infection is prevalent in children and is associated with growth failure. Evaluating the intestinal inflammation of asymptomatic norovirus infection is pivotal to overcoming malnutrition, especially in resource-limited settings. The current study aimed to compare the level of fecal neopterin and calprotectin, as the well-established biomarker for intestinal inflammation, in malnourished children with symptomatic and asymptomatic norovirus infections.

Methods

In total 78 stool samples from children under five years old were analyzed in this comparative study. The 67 of the participants were malnourished children, with 24 had asymptomatic (ANV) and 18 had symptomatic norovirus infection (SNV), while 25 had no infections (Mal). We assigned 11 healthy children without any infection as control (Healthy). We assessed the fecal neopterin and calprotectin from the stools samples collected during viral diarrhea surveillance in Surabaya, East Java, Indonesia, using commercially ELISA kit from BT Lab (Zhejiang, China) for human neopterin and calprotectin. The statistical differences were tested using Kruskal-Wallis nonparametric test.

Results

The level of fecal neopterin (mean ± SD, 15.46 ± 1.75 nmol/L and 15.12 ± 2.41 nmol/L; p-value: 0.744) and calprotectin (mean ± SD, 184.35 ± 35.09 ng/ml and 177.95 ± 49.55 ng/ml; p-value: 0.457) between ANV and SNV was comparable, also between Mal and Healthy groups. Meanwhile, the level of both biomarkers was significantly different in norovirus positive group and norovirus negative group (p-value < 0.000).

Conclusions

Norovirus infection, regardless of the presence of symptoms, triggered intestinal inflammation, represented by the increased of fecal neopterin and calprotectin level.