Skip to main content Accessibility help

Molecular characterization of Cystoisospora belli and unizoite tissue cyst in patients with Acquired Immunodeficiency Syndrome



Cystoisospora belli is a coccidian protozoan that can cause chronic diarrhoea, acalculous cholecystitis and cholangiopathy in AIDS patients. We applied molecular methods to identify Cystoisospora at species level in AIDS patients presenting with and without the presence of unizoites in lamina propria. Coprological and histological analyses were performed in stool and/or biopsy samples from 8 Cystoisospora-infected patients. DNA from the same samples was used to amplify 2 fragments of the SSU-rRNA gene and the ITS-1 region. Sequencing of the resulting amplicons identified C. belli infections in all cases, independent of the presence or absence of unizoite tissue cysts. Further work should be considered in order to find molecular targets related to strain variations in C. belli.


Corresponding author

*Corresponding author: Av. Vélez Sarsfield 563, (CP 1281) Ciudad de Buenos Aires, Argentina. Tel: +54 11 4301 7437. E-mail:


Hide All
Benator, D. A., French, A. L., Beauder, L. M., Levy, C. S. and Orenstein, J. M. (1994). Isospora belli infection associated with acalculous cholecystitis in a patient with AIDS. Annals of Internal Medicine 121, 663664.
Carreno, R. A., Schnitzler, B. E., Jeffries, A. C., Tenter, A. M., Johnson, A. M. and Barta, J. R. (1998). Phylogenetic analysis of coccidia based on 18S rDNA sequence comparison indicates that Isospora is most closely related to Toxoplasma and Neospora. Journal of Eukaryotic Microbiology 45, 184188.
Comin, C. E. and Santucci, M. (1994). Submicroscopic profile of Isospora belli enteritis in a patient with acquired immune deficiency syndrome. Ultrastructural Pathology 18, 473482.
Costa, P. S. and Lopes, C. W. G. (1998). Avaliacação do parasitismo por Cystoisospora felis (Wenyon, 1923) Frenkel, 1977. (Apicomplexa: Cystoisosporinae) em coelhos do tipo carne. Revista Brasileira de Parasitologia Veterinária 7, 1519.
Dubey, J. P. and Frenkel, J. K. (1972). Extra-intestinal stages of Isospora felis and Isospora rivolta (protozoa: eimeriidae) in cats. Journal of Protozoology 19, 8992.
Dubey, J. P. and Mehlhorn, H. (1978). Extraintestinal stages of Isospora ohioensis from dogs in mice. Journal of Parasitology 64, 689695.
Franzen, C., Müller, A., Bialek, R., Diehl, V., Salzberger, B. and Fätkenheuer, G. (2000). Taxonomic position of the human intestinal protozoan parasite Isospora belli as based on ribosomal RNA sequences. Parasitological Research 86, 669676.
Frenkel, J. K., Oliveira Silva, M. B., Saldanha, J. C., De Silva Vergara, M. L., Correia, D., Barata, C. H., Lages Silva, E., Ramirez, L. E. and Prata, A. (2003). Presença extra-intestinal de cistos unizoicos de Isospora belli em paciente com SIDA. Revista da Sociedade Brasileira de Medicina Tropical 36, 409412.
Jongwutiwes, S., Putaporntip, C., Charoenkorn, M., Iwasaki, T. and Endo, T. (2007). Morphologic and molecular characterization of Isospora belli oocysts from patients in Thailand. American Journal of Tropical Medicine and Hygiene 77, 107112.
Lindsay, D. S., Dubey, J. P. and Blagburn, B. L. (1997 a). Biology of Isospora spp. from humans, nonhuman primates, and domestic animals. Clinical Microbiology Reviews 10, 1934.
Lindsay, D. S., Dubey, J. P., Toivio-Kinnucan, M. A., Michiels, J. F. and Blagburn, B. L. (1997 b). Examination of extraintestinal tissue cysts of Isospora belli. Journal of Parasitology 83, 620625.
Maniatis, T., Fritsch, E. F. and Sambrook, J. (1989). Molecular Cloning: A Laboratory Manual. Cold Spring Harbor Laboratory Press, Cold Spring Harbor, NY, USA.
Massad, F. V., Oliveira, F. C. R., Albuquerque, G. R. and Lopes, C. W. G. (2003). Hypnozoítas de Cystoisospora ohioensis (Dubey, 1975) Frenkel, 1977 (Apicomplexa: Cystoisosporinae) em frangos. Revista Brasileira de Ciência Veterinária 10, 5758.
Melo, P., De Carvalho Filho, P. R., Lopes, C. W. G., Flausino, W. and De Oliveira, F. C. R. (2003). Hypnozoítas de Cystoisospora felis (Wenyon, 1923) Frenkel, 1977 (Apicomplexa: Cystoisosporinae) isolated from piglets experimentally infected. Revista Brasileira de Ciência Veterinária 12, 8284.
Michiels, J. F., Hofman, P., Bernard, E., Saint Paul, M. C., Boissy, C., Mondain, V., LeFichoux, Y. and Loubiere, R. (1994). Intestinal and extraintestinal Isospora belli infection in an AIDS patient. Pathology, Research and Practice 190, 10891093.
Mitchell, S. M., Zajac, A. M. and Lindsay, D. S. (2009). Development and ultrastructure of Cystoisospora canis Nemeséri, 1959 (syn. Isospora canis) monozoic cysts in two cell lines. Journal of Parasitology 95, 793798.
Müller, A., Bialek, R., Fätkenheuer, G., Salzberger, B., Diehl, V. and Franzen, C. (2000). Detection of Isospora belli by polymerase chain reaction using primers based on small-subunit ribosomal RNA. European Journal of Clinical Microbiology & Infectious Diseases 19, 631634.
Restrepo, C., Macher, A. M. and Radany, E. H. (1987). Disseminated extraintestinal isosporiasis in a patient with acquired immune deficiency syndrome. American Journal of Clinical Pathology 87, 536542.
Samarasinghe, B., Johnson, J. and Ryan, U. (2008). Phylogenetic analysis of Cystoisospora species at the rRNA ITS1 locus and development of a PCR-RFLP assay. Experimental Parasitology 118, 592595.
Velasquez, J. N., Carnevale, S., Mariano, M., Kuo, L. H., Caballero, A., Chertcoff, A., Ibañez, C. and Bozzini, J. P. (2001). Isosporosis and unizoite tissue cyst in patient with acquired immunodeficiency síndrome. Human Pathology 32, 500505.
Zenta, W. and Topazian, M. D. (2009). Isospora belli cholangiopathy: case study with histologic characterization and molecular confirmation. Human Pathology 40, 13421346.


Related content

Powered by UNSILO

Molecular characterization of Cystoisospora belli and unizoite tissue cyst in patients with Acquired Immunodeficiency Syndrome



Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed.