Transactions of the Royal Society of Tropical Medicine and Hygiene (2004) 98, 193—194 Case report: unusual presentation of Fasciolopsis buski in a Viet Namese child Thanh Hoa Le a , Van De Nguyen b , Ba Uoc Phan c , David Blair d , Donald P McManus e,* a Institute of Biotechnology (IBT), Hanoi, Viet Nam National Institute for Malariology, Parasitology and Entomology (NIMPE), Hanoi, Viet Nam c Centre for Control of Malaria and Parasites, Nghe an Province, Viet Nam d School of Tropical Biology, James Cook University, Townsville, Queensland, Australia e Molecular Parasitology Laboratory, Australian Centre for International and Tropical Health and Nutrition, Queensland Institute of Medical Research and University of Queensland, 300 Herston Road, Q4029, Brisbane, Queensland, Australia b Received May 2003 ; received in revised form 23 June 2003; accepted 24 June 2003 KEYWORDS Fasciolopsis buski; DNA analysis; Praziquantel; Viet Nam Summary A Viet Namese child presented with a history of abdominal pain Shortly afterwards, he vomited eight live trematode flukes that were collected and morphologically identified as Fasciolopsis buski The identification was confirmed by DNA analysis Adult worms of F buski from humans are very rarely seen except at autopsy, and this is the first such report from Viet Nam © 2003 Royal Society of Tropical Medicine and Hygiene Published by Elsevier Ltd All rights reserved Introduction Fasciolopsis buski is a duodenal digenetic trematode (Family: Fasciolidae) parasite occurring in humans but also in pigs, equines, bovines, caprines and ovines that act as reservoir hosts for infection (Chandra, 1984; Segal et al., 1968) Its general morphology is similar to that of the common liver fluke, Fasciola hepatica, but it lacks the thickened anterior cone and its intestinal caeca are unbranched (Smyth, 1994) It is widespread in Asia, occurring in Taiwan, Thailand, Laos, Bangladesh, India and Viet Nam (Chandra, 1984) The intermediate hosts are freshwater planorbid snails that feed on water *Corresponding author Tel.: +61-7-3362-0401; fax: +61-7-3362-0104 E-mail address: donm@qimr.edu.au (D.P McManus) plants such as lotus (Nelumo nucifera), water caltrop (Trapa bicornis), water chestnut (T natana) and other species, much cultivated for food and fertilized with human faeces (night soil) Larval stages (cercariae), periodically released from snails, anchor themselves to water plants where they transform into metacercariae which become enclosed in cysts secreted by the metacercariae The metacercariae-laden water plants are eaten raw and the metacercariae excyst in the small intestine where they develop into adult flukes Case report A two and a half-year-old boy from Vinh City, Nghe an Province, Viet Nam, presented at a local clinic in October 2001, with a prolonged history 0035-9203/$ — see front matter © 2003 Royal Society of Tropical Medicine and Hygiene Published by Elsevier Ltd All rights reserved doi:10.1016/S0035-9203(03)00022-1 194 of abdominal pain Shortly afterwards, he vomited eight live trematode flukes that were collected and forwarded to the Centre for Control of Malaria and Parasites, Nghe an Province for identification The child was treated with praziquantel (25 mg/kg bodyweight/d for d) and completely recovered In association with the National Institute for Malariology, Parasitology and Entomology (NIMPE), Hanoi, Viet Nam, the parasites were fixed, mounted, stained and examined microscopically They were provisionally identified as the giant intestinal fluke, F buski The flukes had the following morphological features: length, 41 mm; width, 13 mm; thickness, mm; and mouth, 0.4 mm; characteristics that were identical to adult specimens of F buski, routinely collected from the intestines of pigs in Viet Nam The provisional identification was confirmed by molecular analysis at The Institute of Biotechnology, Hanoi, Viet Nam Total genomic DNA was extracted from one of the adult flukes using a DNeasy Tissue Kit (Qiagen, Hilden, Germany) A 1.9 kbp fragment of 18S rDNA was amplified by polymerase chain reaction (PCR) using conserved oligonucleotide primers After purification, PCR products were cloned using a TA cloning kit (Invitrogen) and plasmids were extracted using QIAprep Spin Miniprep Kits (Qiagen, Hilden, Germany) DNA inserts were subsequently sequenced using T7 and M-13 reverse primers and an ABI 377 automated DNA sequencer and BigDye sequencing chemistry (ABI, Foster City, CA, USA) The sequences were aligned with a sequence for F buski 18S rDNA deposited in the GenBank database (Accession No T.H Le et al L06668) The sequences were almost identical, with only two nucleotide substitutions evident (2/1900 = 0.1%) between the Viet Namese samples and the sequence deposited in GenBank, indicating that the flukes obtained from the child were indeed F buski Although human cases of F buski infection have been recorded previously in Vietnam, this was by identification of the egg stage in faeces Adult worms of F buski from humans are very rarely seen except at autopsy, and this is the first such report from Viet Nam The combination of morphological and molecular methods provided a very elegant approach to the formal and definitive identification of this important species of flukes Formal consent to undertake the study and for publication of this article was obtained from the parents of the child Acknowledgements This work was supported in part by Wellcome Trust (Ref: 068762) and by the National Health and Medical Research Council of Australia References Chandra, S.S., 1984 Epidemiology of Fasciolopsis buski in Uttar Pradesh Indian J Med Res 78, 55—59 Segal, D.B., Humphrey, J.M., Edwards, S.J., Kirby, M.D., 1968 Parasites of man and domestic animals in Vietnam, Thailand, Laos, and Cambodia Exp Parasitol 23, 412—464 Smyth, J.D., 1994 Introduction to Animal Parasitology Cambridge University Press, Cambridge ... deposited in GenBank, indicating that the flukes obtained from the child were indeed F buski Although human cases of F buski infection have been recorded previously in Vietnam, this was by identification...194 of abdominal pain Shortly afterwards, he vomited eight live trematode flukes that were collected and forwarded to the Centre for Control of Malaria and Parasites, Nghe an Province for... was obtained from the parents of the child Acknowledgements This work was supported in part by Wellcome Trust (Ref: 068762) and by the National Health and Medical Research Council of Australia