Abstract
Neglected Tropical Diseases (NTDs) affect over 2 billion people worldwide, and there is limited information on the association between nutrition and NTDs. This study aimed to determine the role of diet in the pathogenesis of NTDs, particularly in Buruli ulcer (BU), a subcutaneous skin infection caused by Mycobacterium ulcerans.
I conducted a systematic review with meta-analysis to summarize existing knowledge on the association between nutrition and NTDs. I also conducted a case-control study of 40 BU patients and controls using a food frequency and multi-pass 24-hour recall questionnaires to determine their dietary patterns and nutrition status. Based on the outcome of the diet survey, I quantified the serum levels of selected micronutrients and inflammatory biomarkers using ELISA, cytometric bead array and colorimetric assays in 80 BU patients and controls.
The systematic review revealed that, of the 20 NTDs, the links between diet and disease have been explored only for a very few with a paucity of data from low and middle-income countries and least developed countries where the NTD burden is high. In the dietary survey, the diets of the participants were found to be inadequate for their daily needs and many of them had an inadequate intake of macro- and micronutrients (excepting dietary carbohydrate). We found significantly reduced intake of several dietary micronutrients intake among BU cases compared to controls [zinc 5.57 vs. 6.90mg/day (p=0.011), selenium 52.14 vs. 77.32 mg/day (p=0.005) and vitamin B12 0.89 vs. 2.332 µg/day (p=0.002), respectively]. The biomarker study revealed that BU patients had significantly lower levels of serum zinc and vitamin C than controls [zinc 47.63 vs. 63.08 µg/dL (p=0.0001) and vitamin C 0.199 vs. 0.254 mg/dL (p=0.0365), respectively]. There was some evidence for systemic inflammation in a minority of the study population, but these did not differ between patients and controls and IL-6 levels did not correlate with either zinc or vitamin C in the study cohort.
More research into nutrition and infection is recommended, especially for BU since my research showed that micronutrient deficiency is a contributing factor for disease susceptibility. Excitingly, nutritional interventions may have prospects for an adjunct to BU antibiotic treatment.