Hepatosplenomegaly associated with chronic malaria exposure: evidence for a pro‐inflammatory mechanism exacerbated by schistosomiasis
Open Access
- 12 January 2009
- journal article
- Published by Wiley in Parasite Immunology
- Vol. 31 (2), 64-71
- https://doi.org/10.1111/j.1365-3024.2008.01078.x
Abstract
In sub-Saharan Africa, chronic hepatosplenomegaly, with palpable firm/hard organ consistency, is common, particularly among school-aged children. This morbidity can be caused by long-term exposure to malaria, or by Schistosoma mansoni, and it is exacerbated when these two occur together. Although immunological mechanisms probably underlie the pathogenic process, these mechanisms have not been identified, nor is it known whether the two parasites augment the same mechanisms or induce unrelated processes that nonetheless have additive or synergistic effects. Kenyan primary schoolchildren, living in a malaria/schistosomiasis co-transmission area, participated in cross-sectional parasitological and clinical studies in which circulating immune modulator levels were also measured. Plasma IL-12p70, sTNF-RII, IL-10 and IL-13 levels correlated with relative exposure to malaria, and with hepatosplenomegaly. Soluble-TNF-RII and IL-10 were higher in children infected with S. mansoni. Hepatosplenomegaly caused by chronic exposure to malaria was clearly associated with increased circulating levels of pro-inflammatory mediators, with higher levels of regulatory modulators, and with tissue repair cytokines, perhaps being required to control the inflammatory response. The higher levels of regulatory modulators amongst S. mansoni infected children, compared to those without detectable S. mansoni and malarial infections, but exposed to malaria, suggest that S. mansoni infection may augment the underlying inflammatory reaction.Keywords
This publication has 44 references indexed in Scilit:
- Age-adjusted Plasmodium falciparum antibody levels in school-aged children are a stable marker of microgeographical variations in exposure to PlasmodiuminfectionBMC Infectious Diseases, 2007
- Toll-like receptor control of the adaptive immune responsesNature Immunology, 2004
- Detailed clinical and ultrasound examination of children and adolescents in a Schistosoma mansoni endemic area in Kenya: hepatosplenic disease in the absence of portal fibrosisTropical Medicine & International Health, 2004
- Alternative activation of macrophagesNature Reviews Immunology, 2003
- Clinical characteristics and disposition kinetics of the hepatomegaly associated with acute, uncomplicated, Plasmodium falciparum malaria in childrenPathogens and Global Health, 2001
- Hepatomegaly in acute falciparum malaria in childrenTransactions of the Royal Society of Tropical Medicine and Hygiene, 1996
- Nutritional status of children with schistosomiasis mansoni in two different areas of Machakos District, KenyaTransactions of the Royal Society of Tropical Medicine and Hygiene, 1992
- Differences in the rate of hepatosplenomegaly due to Schistosoma mansoni infection between two areas in Machakos District, KenyaTransactions of the Royal Society of Tropical Medicine and Hygiene, 1991
- Asymptomatic malaria infections — Do they matter?Parasitology Today, 1987
- The epidemiology and consequences of Schistosoma mansoni infection in West Nile, Uganda: I. Field studies of a community at PanyagoroTransactions of the Royal Society of Tropical Medicine and Hygiene, 1972