Reciprocal relationships between undernutrition and the parasitic disease visceral leishmaniasis.

Little is known about the interrelationship between undernutrition and parasitic infections in areas of the world where both are prevalent. The associations between undernutrition and visceral leishmaniasis, an important protozoal disease, were assessed in a study of residents of an area in Brazil with endemic leishmaniasis. Mid-arm anthropometry was used to assess fat and muscle area. Children with visceral leishmaniasis came from large families (9.6 +/- 1.1 members vs. 6.8 +/- 0.7 members in neighborhood control families), and patient housemates had fat areas that were 78% (P less than .05) those of age- and sex-matched neighborhood controls. The children with visceral leishmaniasis who were studied four months or less after diagnosis had fat areas that were 66% (P less than .05) those of age- and sex-matched household controls or 41% (P less than .01) those of neighborhood controls and muscle areas that were 81% (P less than .025) those of household controls or 75% (P less than .05) those of of neighborhood controls. It is hypothesized, on the basis of these data and other findings, that undernutrition is associated with the development of clinically apparent visceral leishmaniasis and that the disease itself has a profound effect on nutritional status, resulting in loss of both muscle and fat, effects that possibly are mediated by interleukin-1 and/or other factors produced by Leishmania donovani-infected macrophages.