Pneumocystis jirovecii: a peculiar fungus posing particular problems for therapy and prophylaxis

Pneumocystis jirovecii in immunocompromised patients with rheumatic diseases

Infections, including opportunistic infections, are a major and frequent cause of morbidity and mortality in patients with systemic autoimmune and rheumatic diseases. Pneumocystis jirovecii pneumonia, classically considered to be typical of HIV patients, transplanted patients or patients treated with oncological chemotherapy, is appearing increasingly frequently in these patients. Therefore, rheumatologists should know its mechanism of production, clinical manifestations, treatment and prophylaxis, all of which are addressed in this review.

Development of highly active anti-Pneumocystis bisbenzamidines: insight into the influence of selected substituents on the in vitro activity

Here we describe the potency of 21 pentamidine analogues against the fungal pathogen, Pneumocystis carinii, in an ATP bioluminescent assay with toxicity profiles in 2 mammalian cell lines. Reduction of two 5-methyl-1,2,4-oxadiazole rings was applied to the synthesis of acid-labile bisamidines. Anti-Pneumocystis activity is discussed in the context of 3 groups of compounds depending on the main structural changes of the pentamidine lead structure. The groups include: 1) 1,4-bis(methylene)piperazine derivatives 1-5; 2) alkanediamide derivatives 6-10; 3) alkane-derived bisbenzamidines 11-21. IC50 values of 18 compounds were lower than the IC50 of pentamidine. Four bisamidines were active at nanogram concentrations. Introduction of sulfur atoms in the alkane bridge, replacement of the amidino groups with imidazoline rings, or attachment of nitro or amino groups to the benzene rings is responsible for remarkable activity of the new leading structures. The vast majority of compounds, including four highly active ones, can be classified as mild or nontoxic to host cells. These compounds show promise as candidates for new anti-Pneumocystis agents.

Prevalence of Pneumocystis jirovecii among immunocompromised patients in hospitals of Tehran city, Iran

Pneumocystis jirovecii is an opportunistic organism that can cause extreme complications such as Pneumocystis pneumonia in immunocompromised individuals. There is no comprehensive study was conducted Iran to determine the prevalence of this infection in susceptible individuals. In the present study, 160 sera samples were collected from immunocompromised patients, including acquired immunodeficiency syndrome (AIDS) patients, diabetic patients, Hodgkin lymphoma patients and non-Hodgkin lymphoma patients. The specimens were collected from Imam Khomeini and army's 501 hospitals. The specimens were examined using indirect fluorescent antibody test. The results of the study showed that 39.30% specimens were found positive, with different rates in different groups, including 20, 22.50, 37.50, and 77.50% of diabetic patients, non-Hodgkin patients, Hodgkin lymphoma patients, and AIDS patients, respectively. This occurrence is relatively high and can be a potential life-threatening hazard to infected patients in studied groups, on the other hand the organism can be transmitted from infected people to other susceptible individuals.

Pneumocystis jirovecii Pneumonia in the Non–HIV-Infected Population

Objective: Summarize data on the pathophysiology, treatment, and prevention options for non–AIDS immunocompromised patients who have Pneumocystis jirovecii pneumonia (PJP); review the epidemiology of patients presenting with PJP; and discuss the first and second-line pharmacological options for treatment and prophylaxis of PJP in this population. Data Sources: MEDLINE (1989-February 2016) searched. Terms searched included combinations of Pneumocystis jirovecii, Pneumocystis carinii, non-HIV, infected, patients, prevention, prophylaxis, Bactrim, treatment, AIDS, opportunistic, immunocompromised, cancer, and pathophysiology. Study Selection and Data Extraction: Articles included had the most relevant information on PJP pathophysiology, and first-/second-line treatment and prophylactic options. Inclusion criteria were met and evaluated with 43 sources. Data Synthesis: P jirovecii has a complicated life-cycle; it seeks to find compromised immune systems in order to replicate, causing life-threatening complications. With immunosuppressive medications coming to market for immunomodulating diseases, PJP has become a prevalent opportunistic infection in the non-HIV population. CD4+ lymphocyte count <200 cells/µL is the primary risk factor for PJP presentation in these patients. With data from clinical trials, trimethoprim/sulfamethoxazole (TMP/SMX) has become the primary treatment and prophylaxis of PJP in the non-HIV population, although second-line options are available. Conclusion: PJP is a health problem that may result in an increased concern as more immunomodulating medications to treat various disease states are developed. Patients on these drugs or those with immunosuppressive diseases should have their CD4+ count monitored. Health care providers should continue to use TMP/SMX as the primary option in non-HIV, immunocompromised patients for treatment and prophylaxis of PJP.

Prevalence of Pneumocystis jirovecii pneumonia (2010-2013): the first Croatian report

Pneumocystis jirovecii is an important cause of interstitial pneumonia particularly among immunocompromised hosts. We analysed the prevalence of P. jirovecii pneumonia (PCP) among HIV-infected and HIV-uninfected patients presented with interstitial pneumonia or acute respiratory syndrome hospitalized in six Croatian tertiary care hospitals. Over four-year period (2010-2013), a total of 328 lower respiratory tract samples: 253 (77.1%) bronchoalveolar lavage fluid, 43 (13.1%) tracheal aspirates and 32 (9.8%) bronchial aspirates from 290 patients were examined by real-time polymerase chain reaction (PCR). PCP was detected in 23 (7.9%) patients. The prevalence of PCP differed significantly among tested groups (χ2 = 95.03; d.f. = 3; p < 0.001). HIV-infected patients were more often positive (56.6%, 95%CI = 37.3-72.4) compared to other groups (patients with malignant disease 7.7%, 95%CI = 2.6-20.3; transplant patients 7.7%, 95%CI = 2.2-24.1; patients with other diagnosis 1.5%, 95%CI = 0.5-4.4). Majority of HIV-positive patients (80%) were newly diagnosed cases. Our results indicate that HIV-infected patients still represents the main risk group for P. jirovecii infection. PCP is responsible for pneumonia in 56.6% HIV-positive patients in Croatia, primarily those who do not know that they are HIV infected.