HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in ISI Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Jongwutiwes, S. Articles by Endo, T. Search for Related Content PubMed PubMed Citation Articles by Jongwutiwes, S. Articles by Endo, T. Related Collections HIV Isosporaisis

Morphologic and Molecular Characterization of Isospora belli Oocysts from Patients in Thailand

To investigate the extent of genetic heterogeneity in the genus Isospora infecting patients in Thailand, a total of 38 fecal samples containing Isospora oocysts from human immunodeficiency virus/acquired immunodeficiency syndrome patients (n = 30), corticosteroid-treated patients (n = 3) and immunocompetent individuals (n = 5) were recruited for analysis. Remarkable variation in the maximum width and length of oocysts both within and between isolates was observed. However, the average length-width ratio of oocysts was within the range for I. belli (> 1.2). Ex vivo sporogonic development of freshly passed oocysts in feces from three of these isolates was observed longitudinally, showing that 27% of these oocysts underwent complete sporulation. Interestingly, 95% of sporulated oocysts contained two sporocysts in an oocyst with four sporozoites in each sporocyst, and Caryospora-like oocysts, characterized by eight sporozoites enclosed by a single sporocyst, were also detected (5%). The small subunit ribosomal RNA (rRNA), 5.8S rRNA, internal transcribed spacer 1 (ITS-1), and ITS-2 were highly conserved, indicating that there were no cryptic species or extensive strain variation.

Received December 29, 2006. Accepted for publication March 12, 2007.

Acknowledgments: We are grateful to all patients who participated in this study, and to Professors Hiroji Kanbara and Haruo Watanabe for valuable support.

Financial support: This study was supported by the Ministry of Labor and Welfare of Japan through The National Institute of Infectious Diseases (Tokyo); the Ratchadapiseksompotch Fund from the Faculty of Medicine, Chulalongkorn University (grant no. RA227/48); funds for devoted scholar from the Ananthamahidol Foundation to Somchai Jongwutiwes, and funds from the Faculty of Medicine, Chulalongkorn University to Somchai Jongwutiwes and Chaturong Putaporntip.

^* Address correspondence to Somchai Jongwutiwes, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand. E-mail: fmedsjw{at}md2.md.chula.ac.th

Authors’ addresses: Somchai Jongwutiwes, Chaturong Putaporntip, and Malee Charoenkorn, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Rama 4 Road, Pathumwan, Bangkok 10330, Thailand. Takuya Iwasaki, Department of Laboratory Investigation, Institute of Tropical Medicine, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 8528523, Japan; and Division of Laboratory Medicine, National Iwate Hospital, Iwate 0210056, Japan. Takuro Endo, Department of Parasitology, National Institute of Infectious Diseases, Toyama 1-23-1, Shinjuku-ku, Tokyo 162-8640, Japan.

Reprint requests: Somchai Jongwutiwes, Department of Parasitology, Faculty of Medicine, Chulalongkorn University, Bangkok 10330, Thailand, Telephone: 66-2-256-4000 extension 3685, Fax 66-2-252-4963, E-mail: fmedsjw{at}md2.md.chula.ac.th.