A multi-centered study of Pneumocystis jirovecii colonization in patients with respiratory disorders: Is there a colonization trend in the elderly?

BACKGROUND AND PURPOSE: Pneumocystis jirovecii colonization plays a key role in the progression of pulmonary infection. However, there are limited data regarding the colonization of these fungi in the patients residing in different regions of Iran. Regarding this, the present study was conducted to evaluate the prevalence of P. jirovecii colonization in non-HIV-infected patients with respiratory failure introduced by physicians using nested polymerase chain reaction (PCR). MATERIALS AND METHODS: This study was conducted on 136 samples obtained from 136 patients with respiratory disorders referring to different hospitals in the capital and north of Iran during 2013-2015. The samples were collected using bronchoalveolar lavage (BAL; n=121) and sputum induction (n=15). Nested PCR method targeting mtLSU rRNA gene was used for the detection of P. jirovecii DNA in the specimens. RESULTS: The nested PCR analysis resulted in the detection of P. jirovecii DNA in 32 (23.5%) patients. The mean age of the participants was 49.04±11.94 years (age range: 14-90 years). The results revealed no correlation between Pneumocystis colonization and gender. The studied patients were divided into two groups of immunocompromised and immunocompetent patients. In the regard, 25.4% of the patients with detectable P. jirovecii DNA were immunocompromised and had cancer, organ transplantation, asthma, sarcoidosis, dermatomyositis, chronic obstructive pulmonary disease, bronchiectasis, and pulmonary vasculitis. On the other hand, Pneumocystis DNA was detected in 21.8% of the immunocompetent patients. Frequencies of P. jirovecii DNA detection in the patients with tuberculosis, hydatid cyst, and unknown underlying diseases were obtained as 20.8%, 25%, and 22%, respectively. The prevalence of Pneumocystis colonization varied based on age. In this regard, P. jirovecii colonization was more prevalent in patients aged above 70 years. CONCLUSION: As the findings indicated, non-HIV-infected patients, especially the elderly, had a high prevalence of P. jirovecii colonization. Therefore, these patients are probably a potential source of infection for others. Regarding this, it is of paramount importance to adopt monitoring and prophylactic measures to reduce this infection.

Co-infection of Mycobacterium tuberculosis and Pneumocystis jirovecii in the Iranian Patients With Human Immunodeficiency Virus.

BACKGROUND: Based on the authors' knowledge, there is no study on the co-infection of opportunistic agents such as Mycobacterium tuberculosis and Pneumocystis jirovecii in the lungs of Iranian patients with immunosuppression. OBJECTIVES: The current study aimed to show the rate of co-infection of M. tuberculosis and P. jirovecii in patients with Human Immunodeficiency Virus (HIV). PATIENTS AND METHODS: Forty-five pulmonary samples were collected from 30 patients with HIV who also infected with Tuberculosis and Pneumonia. All of the patients were admitted to two university hospitals of Mycobacteriology and the Iranian HIV/AIDS research centers. DNA of P. jirovecii was detected using nested-Polymerase Chain Reaction (nested-PCR) assay. RESULTS: All of the patients were male with the mean age of 32.95 ± 7.15 years. The mean of CD4 cell count was 109.25 cell/mm(3). Of 30 patients with HIV, three (10%) were co-infected with M. tuberculosis and P. jirovecii. No other causes of pneumonia were found in those three patients and CD4 cell counts less than 50 cell/mm(3) was reported. CONCLUSIONS: The results of the current study showed a high rate of co-infection of M. tuberculosis and P. jirovecii in the Iranian patients with HIV. As the immune system condition worsened, the probability of occurrence of Pneumocystis Pneumonia (PCP) increased. Therefore, more specific, most rapid and sensitive tests should be utilized for diagnosis of PCP in this group of patients.

Dihydropteroate synthase gene mutation rates in Pneumocystis jirovecii strains obtained from Iranian HIV-positive and non-HIV-positive patients.

The dihydropteroate sulfate (DHPS) gene is associated with resistance to sulfa/sulfone drugs in Pneumocystis jirovecii. We investigated the DHPS mutation rate in three groups of Iranian HIV-positive and HIV-negative patients by polymerase chain reaction-restricted fragment length polymorphism analysis. Furthermore, an association between P. jirovecii DHPS mutations and strain typing was investigated based on direct sequencing of internal transcribed spacer region 1 (ITS1) and ITS2. The overall P. jirovecii DHPS mutation rate was (5/34; 14.7%), the lowest rate identified was in HIV-positive patients (1/16; 6.25%) and the highest rate was in malignancies patients (3/11; 27.3%). A moderate rate of mutation was detected in chronic obstructive pulmonary disease (COPD) patients (1/7; 14.3%). Most of the isolates were wild type (29/34; 85.3%). Double mutations in DHPS were detected in patients with malignancies, whereas single mutations at codons 55 and 57 were identified in the HIV-positive and COPD patients, respectively. In this study, two new and rare haplotypes were identified with DHPS mutations. Additionally, a positive relationship between P. jirovecii strain genotypes and DHPS mutations was identified. In contrast, no DHPS mutations were detected in the predominant (Eg) haplotype. This should be regarded as a warning of an increasing incidence of drug-resistant P. jirovecii strains.

High prevelance of rifampin-monoresistant tuberculosis: a retrospective analysis among Iranian pulmonary tuberculosis patients.

We determined the prevalence of rifampin-monoresistant tuberculosis (RMR-TB) in Iran. Because development of RMR-TB is not common, we also identified the major risk factors associated with RMR-TB reported from different provinces of Iran. Data for 3,020 TB patients who remained or became smear positive after two, four, six, and nine months of standard first-line chemotherapy were retrospectively analyzed. Of 3,020 patients, 1,242 patients (41.1%) were culture and DNA positive for Mycobacterium tuberculosis. Of these patients, 73 (7.4%) patients had monoresistant isolates to rifampin, which was significantly higher than that for multidrug-resistant TB (5.8%). The average rate of RMR-TB in the studied population ranged from 5% to 10%. Classical investigation showed that 33.6% of patients had either a previous or family history of TB. Molecular epidemiology methods (i.e., spoligotyping and Mycobacterium interspersed repetitive unit-variable number tandem repeat), defined transmission link in three clusters (13%). These results outline the urgent need for a comprehensive plan for detection and treatment of RMR-TB cases.

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

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.

Colonization of Pneumocystis jirovecii in Chronic Obstructive Pulmonary Disease (COPD) patients and the rate of Pneumocystis pneumonia in Iranian non-HIV(+) immunocompromised patients.

BACKGROUND AND OBJECTIVES: With increasing rate of immunodeficiency diseases in the world, opportunistic micro-organism such as Pneumocystis jirovecii (P. jirovecii) become more important. Little information is available on prevalence of this life-threatening microorganism in Iran. This study was designed to determine the colonization and the rate of active disease caused by P. jirovecii in two groups of Iranian immunosuppressed patients. MATERIALS AND METHODS: Two hundred and fifty five pulmonary samples were collected from two groups of immunosuppressed patients to detect a 260bp fragment of mt LSU rRNA gene of P. jirovecii by nested PCR. The first group was COPD patients consumed oral, inhaled or injectable corticosteroid and the second group was patients with malignancies under chemotherapy. Both groups were referred to National Research Institute of Tuberculosis and Lung Disease and Imam Khomeini hospital because of pulmonary symptoms. All patients introduced to this project were confirmed HIV sera-negative by ELISA and western blot test. RESULTS: The mean age of COPD patients was 66.5 ± 11 (41-88) years and all of them were men. The mean age of patients with malignancy (PMs) was 43 ± 11 (23-65) years and 51.6% were men. The P. jirovecii was colonized in 7 of 89 COPD patients (7.9%) and its DNA was isolated from 11 of 153 PMs (7.2%). The microorganism could cause active disease in 7 of 67 (10.5%) PMs who suffered from pneumonia. CONCLUSION: The study showed that P. jirovecii was one of colonizing agents in the COPD patients, but it could cause active disease in PMs. Generally, the microorganism can exist in the lung of non-HIV(+) immunosuppressed patients. Therefore, it should be considered as a potential infective agent in non-HIV(+) immunocompromised patients.