Detailed clinical and ultrasound examination of children and adolescents in a Schistosoma mansoni endemic area in Kenya: hepatosplenic disease in the absence of portal fibrosis Birgitte J. Vennervald 1 , LeeCarol Kenty 2 , Anthony E. Butterworth 3 , Curtis H. Kariuki 4 , Hilda Kadzo 5 , Edmund Ireri 6 , Clifford Amaganga 6 , Gachuhi Kimani 6 , Joseph Mwatha 6 , Amos Otedo 6 , Mark Booth 2 , John H. Ouma 6 and David W. Dunne 2 1 Danish Bilharziasis Laboratory, Charlottenlund, Denmark 2 Division of Microbiology and Parasitology, Department of Pathology, University of Cambridge, Cambridge, UK 3 Biomedical Research and Training Institute, Harare, Zimbabwe 4 Division of Vector Borne Diseases, Ministry of Health, Nairobi, Kenya 5 Kenyatta National Hospital, Nairobi, Kenya 6 Kenya Medical Research Institute, Nairobi, Kenya Summary Hepatosplenic schistosomiasis involving organomegaly, portal fibrosis and portal hypertension has been observed in autopsy studies. Here, we have tested the hypothesis that hepatosplenic disease including organomegaly and markers of increased portal pressure can occur in school aged children in the absence of fibrosis. A case-only study of 96 children aged 7–20 years defined by ultrasound detectable hepatomegaly was undertaken in Makueni district, Kenya. A novel method of clinical examination that involved a consensus scoring by three or four examiners was used to classify children as presenting with severe or moderate hepatosplenic disease after palpation of livers and spleens. Ultrasound examination of livers and spleens was based on the Niamey protocol. Clinical measurements included spleen enlargement along the mid-clavicular and mid-axillary lines, liver enlargement along the mid-sternal (MSL) and mid-clavicular lines, as well as organ consistency. The clinical examination indicated that 9% and 60% of the children had severe or moderate hepatosplenomegaly, respectively. Amongst egg- positive children, all clinical measurements, except MSL liver enlargement, correlated with egg count, as did portal vein diameter, spleen length and liver length measured by ultrasound. Peri-portal fibrosis was not observed in any child, whereas 28% of the children were classified as having increased portal pressure according to World Health Organization criteria. There was no effect of malaria parasitaemia or hepatitis seropositvity on any of the observed parameters. These results indicate that hepatosplenic disease in school-aged children attributable to S. mansoni infection, involving hepatosplenomegaly and increased portal vein diameter, can occur in the absence of peri-portal fibrosis. keywords Schistosoma mansoni, hepatomegaly, splenomegaly, ultrasonography, schistosomiasis Introduction Hepatosplenic schistosomiasis (HS) is a severe clinical manifestation of Schistosoma mansoni infection, charac- terized by enlargement of the liver and spleen and accompanied by increased firmness of the organs (Mackenjee et al. 1984). Schistosome eggs pass, via the portal vein, to the liver, where they give rise to vascular, inflammatory and granulomatous changes. The granulo- matous pyelophlebitis and peripyelophlebitis can lead to increased portal pressure resulting in portal hypertension (Bogliolo 1957). This may result in the development of oesophageal varices with the risk of haematemesis, which can be life threatening. In autopsy studies in Brazil (Cheever & Andrade 1967) and Egypt (Mosimann et al. 1978), hepatosplenic disease with portal hypertension was associated exclusively with Symmers’ pipestem fibrosis and was characterized by development of fibrosis along the branches of the portal tract with marked thickening of the blood vessel walls. Portal hypertension was not associated with lesser lesions such as fibrosis of small portal tracts or inflammatory infiltrates (Cheever & Andrade 1967). Despite the close association of HS, portal hypertension and Symmers’ pipestem fibrosis at autopsy, a number of observations suggest they are not highly dependent at the Tropical Medicine and International Health volume 9 no 4 pp 461–470 april 2004 ª 2004 Blackwell Publishing Ltd 461