Typing of Pneumocystis jirovecii isolates from Iranian immunosuppressed patients based on the Internal Transcribed Spacer (ITS) region of the rRNA gene

Abstract

Since there have been no published molecular studies of Pneumocystis jirovecii isolates from Iranian patients, we investigated the genotypes of such isolates recovered from HIV-infected patients, those undergoing cancer chemotherapy and patients with chronic obstructive pulmonary disease (COPD). P. jirovecii typing, based on ITS1 and ITS2 sequence analysis, was performed on 34 isolates from Iranian immunosuppressed patients. In total, 44 genotypes were detected of which relative to ITS1, eight known genotypes (A, B, C, E, G, H, N and O) and one novel sequence were noted. Eight known genotypes (b, c, e, g, h, i, j and n) were also found with ITS2. The most frequent ITS1 and ITS2 genotypes were E (21/44, 47.7%) and g (22/44, 50%), respectively. From determined haplotypes, the four most frequent ones were Eg (11/44, 25%), Gg (5/44, 11.3%), Gi (4/44, 9.1%), Ei (3/44, 6.8%), and Hg (3/44, 6.8%). Two novel haplotypes (Hb and Hi) were also identified, along with mixed infections as seven (20.5%) patients were found to have more than one haplotype. It is suggested that novel haplotypes in Iranian patients may be generated through sexual recombination within the host.

Keywords:

• Pneumocystis jirovecii
• immunosuppressed patients
• genotyping
• Internal Transcribed Spacer 1 (ITS1)
• Internal Transcribed Spacer 2 (ITS2)
• ribosomal DNA
• DNA sequencing

Acknowledgments

The authors thank Dr Payam Tabarsi (Mycobacteriology Research Center) for presenting HIV-positive patients, and also Dr AliReza Nadji (Virology Research Center) for providing DNA from AECOPD patients and Dr Majid Pirestani (Tarbiat Modares University) for identifying cancer patients, Mrs Leila Moazami (Head nurse of HIV/AIDS Research Center) for collecting samples from HIV-positive patients, and also Mr Kasra Vahidi and Akbar Nikzad Farokhi for editing the text. This work was supported in part by the Iranian HIV/AIDS Research Center, Mycobacteriology Research Center/National Research Institute of Tuberculosis and Lung Disease, and Tarbiat Modares University.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and the writing of the paper.

This paper was first published online on Early Online on 17 July 2013.