Pneumocystis jirovecii previously known Pneumocystis carinii is the cause of opportunistic infections in the lower respiratory tract of immunocompromised hosts mainly among patients with HIV infected, hematologic malignancies, congenital immunodeficiency, organ transplant recipients, and patients receiving immunosuppressive drugs [1]. The organism was considered as one of the most leading cause...

Pneumocystis fungi represent a highly diversified biological group with numerous species, which display a strong host-specificity suggesting a long co-speciation process. In the present study, the presence and genetic diversity of Pneumocystis organisms was investigated in 203 lung samples from woodmice (Apodemus sylvaticus) collected on western continental Europe and Mediterranean islands. The...

B cells play a critical role in the clearance of Pneumocystis. In addition to production of Pneumocystis-specific Abs, B cells are required during the priming phase for CD4(+) T cells to expand normally and generate memory. Clearance of Pneumocystis was found to be dependent on Ag specific B cells and on the ability of B cells to secrete Pneumocystis-specific Ab, as mice with B cells defective ...

Pneumocystis pneumonia (PcP) remains a significant cause of morbidity and mortality in immunocompromised persons, especially those with human immunodeficiency virus (HIV) infection. Pneumocystis colonization is described increasingly in a wide range of immunocompromised and immunocompetent populations and associations between Pneumocystis colonization and significant pulmonary diseases such as ...

The primary infection by Pneumocystis of normal, healthy infants is asymptomatic and goes undiagnosed. Microscopy diagnosis of Pneumocystis was sought in lung impression smears (LIS) from two ~3-month-old infants dying unexpectedly in the community. Pneumocystis nuclei and cysts were identified using Hema-Gurr with subsequent Gomori-Grocott staining in the same spot documenting that these stain...

Leukemia is the most common malignancy in children which leads to immunosuppression and predisposes patients to opportunistic infections. We report a 12-year-old girl with acute lymphoblastic leukemia (ALL) who developed simultaneous infection with pneumocystis Jirovecii pneumonia and aspergillosis in the induction phase of chemotherapy. The patient developed pulmonary cavitation and pneumothor...

Pneumocystis was first described in 1909 as an evolutionary phase in the life cycle of Trypanosoma cruzi by Chagas [1]. Later it was defined as a different organism [2]. Pneumocystis pathogenesis in humans was shown in 1951 for the fist time [3]. Recently, a species of Pneumocystis which afflicts humans was named Pneumocystis jiroveci [4]. Pneumocystis pneumonia (PCP) has remained as one of the...

BACKGROUND AND PURPOSE Pneumocystis pneumonia, caused by Pneumocystis jirovecii, is a fatal disease threatening patients with AIDS or immunosuppression. Assessment of colonization in these patients is of great significance, since it can lead to severe pulmonary disorders. Considering the scarcity of published reports on Pneumocystis jirovecii isolates from patients in Mashhad, Iran, we aimed to...

Pulmonary colonization by the opportunistic pathogen Pneumocystis jiroveci is common in HIV(+) subjects and has been associated with development of chronic obstructive pulmonary disease (COPD). Host and environmental factors associated with colonization susceptibility are undefined. Using a simian-human immunodeficiency virus (SHIV) model of HIV infection, the immunologic parameters associated ...

Diagnosis of pneumocystis pneumonia is based on identifying Pneumocystis carinii cytochemically in material from the lung. The silver methenamine staining methods most commonly used are technically difficult and lack specificity. The diagnostic value of immunocytological identification of the parasite was evaluated by using mouse monoclonal antibody 3F6, specific for human pneumocystis, to iden...