Nutritional supplements for patients who are being treated for active visceral leishmaniasis

What is the aim of this review

The aim of this Cochrane review was to find out whether oral nutritional supplements could help people who were being treated for visceral leishmaniasis (VL). We tried to collect and analyse all relevant studies that answered this question.

Key messages

We found no trials, either completed or ongoing, that answered our review question. Thus, good quality evidence on the effects of oral nutritional supplements in people who are being treated with anti-leishmanial drug therapy is needed. This evidence could be obtained if a large, well done, randomized clinical trial was undertaken.

What was studied in this review

VL, also known as kala-azar, is an infection that has a worldwide distribution. It can lead to death if untreated. Malnutrition and VL are interconnected health problems. On the one hand, malnutrition may hasten the progression of the infection, while on the other hand, VL worsens the malnutrition status of the individual. Also, if a person with VL is malnourished, she or he does not respond as well to the treatment for leishmaniasis. As VL frequently affects people living in poor countries, with limited access to optimal diets, giving additional nutrients to people receiving treatment for VL may improve their nutrition, and thus, their health.

We searched for trials that evaluated the effects of providing any oral nutritional supplement, compared with placebo, dietary advice, or no nutritional intervention, in people who were being treated for VL.

What are the main results of this review?

We found no trials, either completed or ongoing, that answered our review question. Thus, there is no high quality evidence from trials to inform healthcare professionals about the effects of oral nutritional supplements in people who are being treated for VL.

This absence of evidence should not be interpreted as evidence of no effect for nutritional supplements in people under VL treatment. It means that we did not identify any eligible research for this review, and that the effects of oral nutritional supplements have yet to be determined by rigorous studies.

How up-to-date is this review

We searched for studies that had been published up to 12 September 2017.

Authors' conclusions: 

We found no studies, either completed or ongoing, that assessed the effects of oral nutritional supplements in people with VL who were being treated with anti-leishmanial drug therapy. Thus, we could not draw any conclusions on the impact of these interventions on primary cure of VL, definitive cure of VL, treatment completion, self-reported recovery from illness or resolution of symptoms, weight gain, increased skinfold thickness, other measures of lean or total mass, or growth in children.

This absence of evidence should not be interpreted as evidence of no effect for nutritional supplements in people under VL treatment. It means that we did not identify research that fulfilled our review inclusion criteria.

The effects of oral nutritional supplements in people with VL who are being treated with anti-leishmanial drug therapy have yet to be determined by rigorous experimental studies, such as cluster-randomized trials, that focus on outcomes relevant for patients.

Read the full abstract...
Background: 

Visceral leishmaniasis (VL) is a disease caused by a parasite, which can lead to death if untreated. Poor nutritional status hastens the progression of VL infection, and VL worsens malnutrition status. Malnutrition is one of the poor prognostic factors identified for leishmaniasis. However, the effects of nutritional supplementation in people treated for VL are not known.

Objectives: 

To assess the effects of oral nutritional supplements in people being treated with anti-leishmanial drug therapy for VL.

Search strategy: 

We searched the Cochrane Infectious Diseases Group (CIDG) Specialized Register, CENTRAL, MEDLINE, Embase, LILACS, and two trial registers up to 12 September 2017. We checked conference proceedings and WHO consultative meeting reports, the reference lists of key documents and existing reviews, and contacted experts and nutritional supplement companies.

Selection criteria: 

Randomized controlled trials (RCTs), quasi-randomized controlled trials (quasi-RCTs), and non-randomized controlled trials (NRCTs) of any oral nutritional supplement, compared to no nutritional intervention, placebo, or dietary advice alone, in people being treated for VL.

Data collection and analysis: 

Two review authors independently screened the literature search results for studies that met the inclusion criteria. We had planned for two review authors to independently extract data and assess the risk of bias of the included studies. We planned to follow the Cochrane standard methodological procedures for assessing risk of bias and analysing the data.

Main results: 

We identified no eligible studies for this review, either completed or ongoing.