Hepatosplenic morbidity due to Schistosoma mansoni in schoolchildren on Ukerewe Island, Tanzania
- 164 Downloads
The study was conducted to assess infection intensity and morbidity due to Schistosoma mansoni in schoolchildren on Ukerewe Island in Lake Victoria, Tanzania, East Africa. Three hundred and sixty pupils who have never been treated previously were enrolled (180 males/180 females, age 6–17 years [median 10 years]) in three different schools of the island. Double stool samples were collected from each pupil and egg excretion was classified according to WHO recommendations. Ultrasound investigations were performed in accordance with the WHO Niamey-Belo-Horizonte protocol. Male (112/180, 62.2%) and female (104/180; 57.7%) pupils were infected (difference, not significant [n.s.]). In the positive 216 cases, egg excretion varied from 1 to 2,440 eggs per gramme stool (epg) [median 165 epg]. There were 69/216 (31.9%) who had a low grade, 105/216 (53.2%) had a moderate and 42/216 (14.8%) had a heavy infection. There was no significant difference between male and female sex nor with regard to age groups. There were 354/360 children who underwent sonography: 321 (90.7%) had splenomegaly, 316 (89.3%) showed a left lobe and 109 (30.9%) had a right lobe hepatomegaly. Overt signs of portal fibrosis (PF) were present in 19 children (5.4%) out of whom 11 presented with echogenic thickening of peripheral portal and 8 with thickening of central portal branches. Non-specific portal wall changes were seen in 6 children (1.7%). Association of PF to quantitative egg excretion was not seen (median in PF, 172 epg vs. median in non PF, 168 epg; difference, n.s.). Portal vein dilatation was seen in 101/354 (28.5%) cases. In Ukerewe, the prevalence of S. mansoni infection and infection intensity in children is high, yet overt hepatic morbidity is low as compared to other endemic foci. Non-specific ultrasonographic abnormalities including hepatosplenomegaly and portal vein dilatation were seen frequently but the fraction attributable to schistosomiasis is difficult to assess.
KeywordsSchistosomiasis Esophageal Varix Gallbladder Wall Infection Intensity Schistosoma Mansoni
First and foremost, we thank the children for their kindness and cooperation, as well as for their curiosity which made this trip more than a study. Furthermore, we thank all members of the NIMR field team and the local representatives for their invaluable help. We were overwhelmed by the hospitality and cooperation of the three participating schools in Gallu, Mahande and Hamkoko. The study was funded by the Section of Tropical Medicine of Heinrich Heine University Düsseldorf, Germany and Friedrich-Ebert-Stiftung, Bonn and Berlin, Germany. Special thanks to Mr. Laban Aggrey founder and director of the Non-Governmental Organization for “Development of Free Education Services Centers for Orphans” (DEFESCO) in Mwanza, Tanzania, for his critical review of the manuscript
- Blanton RE, Salam EA, Ehsan A, King CH, Goddard KA (2005) Schistosomal hepatic fibrosis and the interferon gamma receptor: a linkage analysis using single-nucleotide polymorphic markers. Eur J Hum Genet 13(5):660–668Google Scholar
- Cohen HL, Sivit CJ (2000) Fetal and pediatric ultrasound: a casebook approach, 1st edn. McGraw Hill, Philadelphia U.S.A, p 224, ISBN-10: 0838588646, ISBN-13: 978-0838588642Google Scholar
- Dessein AJ, Hillaire D, Elwali NE, Marquet S, Mohamed-Ali Q, Mirghani A, Henri S, Abdelhameed AA, Saeed OK, Magzoub MM, Abel L (1999) Severe hepatic fibrosis in Schistosoma mansoni infection is controlled by a major locus that is closely linked to the interferon-gamma receptor gene. Am J Hum Genet 65:709–721PubMedCrossRefGoogle Scholar
- Doehring-Schwerdtfeger E, Mohamed Ali Q, Abdel-Rahim IM, Kardorff R, Franke D, Kaiser C, Elsheikh M, Ehrich JHH (1989) Sonomorphological abnormalities in Sudanese children with Schistosoma mansoni infection: a proposed staging-system for field diagnosis of periportal fibrosis. Am J Trop Med Hyg 41:63–69PubMedGoogle Scholar
- Homeida M, Ahmed S, Dafalla A, Suliman S, Eltom I, Nash T, Bennett JL (1988) Morbidity associated with Schistosoma mansoni infection as determined by ultrasound: a study in Gezira, Sudan. Am J Trop Med Hyg 39:196–201Google Scholar
- Høost U, Kelbaek H, Rasmusen H, Court-Payen M, Christensen NJ, Pedersen-Bjergaard U, Lorenzen T (1996) Haemodynamic effects of eating: the role of meal composition. Clin Sci (Lond) 90(4):269–276Google Scholar
- Kabatereine NB (2000) Discussion. Schistosoma mansoni in a fishing community on the shores of Lake Albert at Butiaba, Uganda: epidemiology, morbidity, re-infection patterns and impact of treatment with praziquantel. PhD Thesis, Vector Control Division, Ministry of Health Uganda, Faculty of Science, University of Copenhagen and Danish Bilharziasis Laboratory, Copenhagen Denmark, pp. 73–75.Google Scholar
- Kabatereine NB, Kemijumbi J, Ouma JH, Sturrock RF, Butterworth AE, Madsen H, Ornbjerg N, Dunne DW, Vennnervald BJ (2003) Efficacy and side effects of praziquantel treatment in a highly endemic Schistosoma mansoni focus at Lake Albert, Uganda. Trans R Soc Trop Med Hyg 97:599–603PubMedCrossRefGoogle Scholar
- Kardorff R, Gabone RM, Mugashe C, Obiga D, Ramarokoto CE, Mahlert C, Spannbrucker N, Lang A, Gunzler V, Gryseels B, Ehrich JH, Doehring E (1997) Schistosoma mansoni-related morbidity on Ukerewe Island, Tanzania: clinical, ultrasonographical and biochemical parameters. Trop Med Int Health 2:230–239PubMedCrossRefGoogle Scholar
- Katz N, Chaves A, Pellegrino J (1972) A simple device for quantitative thick smear technique in Schistosomiasis mansoni. Rev Inst Med Trop São Paulo 14:97–100Google Scholar
- King CH, Magak P, Salam EA, Ouma JH, Kariuki HC, Blanton RE (2003) Measuring morbidity in Schistosomiasis mansoni: relationship between image pattern, portal vein diameter and portal branch thickness in large-scale surveys using new WHO coding guidelines for ultrasound in schistosomiasis. Trop Med Int Health 8(2):109–117PubMedCrossRefGoogle Scholar
- Mohamed Ali Q, Doehring-Schwerdtfeger E, Abdel-Rahim IM, Schlake J, Kardorff R, Franke D, Kaiser C, Elsheikh M, Ehrich JHH (1991) Ultrasonographical investigation of periportal fibrosis in children with Schistosoma mansoni infection: reversibility of morbidity seven months after treatment with praziquantel. Am J Trop Med Hyg 44:444–451PubMedGoogle Scholar
- Niamey Working Group. Richter J, Hatz C, Campagne G, Jenkins J edts. (2000) Ultrasound in Schistosomiasis. A practical guide to the standardized use of ultrasonography for the assessment of schistosomiasis-related morbidity. WHO, www.who.int/tdr.
- Richter J, Zwingenberger K, Mohamed-Ali Q, Moura Lima W, Dacal ARC, Vergetti Siqueira G, Doehring-Schwerdtfeger E, Feldmeier H (1992a) Hepatosplenic schistosomiasis: comparison of sonographic findings in Brazilian and Sudanese Patients—correlation of sonographic findings with clinical symptoms. Radiology 184:711–716PubMedGoogle Scholar
- Richter J, Silva Monteiro E, Moreira Braz R, Abdalla M, Abdel-Rahim IM, Fano U, Huntgeburth U, Feldmeier H (1992b) Sonographic organometry in Brazilian and Sudanese patients with hepatosplenic Schistosomiasis mansoni and its relation to the risk of bleeding from oesophageal varices. Acta Trop 51:281–290PubMedCrossRefGoogle Scholar
- World Health Organization (2001) Report of the WHO informal consultation on schistosomiasis in low transmission areas: control strategies and criteria for elimination. London 10–13 April 2000. WHO/CDS/CPE/SIP/SIP2001.1; www.who.int/ctd.
- Yazdanpanah Y, Thomas AK, Kardorff R, Talla I, Sow S, Niang M, Stelma FF, Decam C, Rogerie F, Gryseels B, Capron A, Doehring E (1997) Organometric investigations of the spleen and liver by ultrasound in Schistosoma mansoni endemic and nonendemic villages in Senegal. Am J Trop Med Hyg 57:245–249PubMedGoogle Scholar