Pneumocystis jirovecii infection in patients with acute interstitial pneumonia

Genetic Polymorphisms of Superoxide Dismutase Locus of Pneumocystis jirovecii in Spanish Population

Objective:Pneumocystis pneumonia remains a major opportunistic infection in immunocompromised patients worldwide. Colonization with Pneumocystis jirovecii has recently gained attention as an important issue for understanding the complete cycle of human Pneumocystis infection. P. jirovecii Superoxide Dismutase (SOD) gene could be a molecular target with high clinical relevance, but the epidemiological information about SOD genotypes distribution is scarce. The aim of this work was to provide information about the prevalence of genotypes of Pneumocystis SOD among Spanish patients and to describe possible differences between colonized and Pneumocystis pneumonia patients.

Methods: we developed a cross-sectional study analyzing broncho-alveolar lavage fluid samples from 30 Pneumocystis pneumonia patients, 30 colonized patients, and 20 controls using a nested PCR protocol designed to amplify the sodA gene of P. jirovecii. The diagnostic yield of SOD Nested PCR was evaluated against the routine practice of mtLSUrRNA Nested PCR, which is considered the gold standard.

Results: SOD locus was amplified in 90% of Pneumocystis pneumonia patients, 10% of colonized patients, and none of controls. Genotype SOD1 was observed in 11 cases (52.4%) and genotype SOD2 in 10 cases (47.6%). Genotype SOD2 was observed only in Pneumocystis pneumonia patients while the genotype SOD1 was observed in both colonized and Pneumocystis pneumonia patients.

Conclusions: This study provides epidemiological information about SOD genotypes distribution in Spain, showing a low genetic diversity and a predominant presence of genotype SOD1 in colonized patients. SOP Nested PCR was more sensitive and accurate assay in Pneumocystis pneumonia patients than in colonized individuals.

Pneumocystis jirovecii in Spanish Patients With Heart Failure

Objective:Pneumocystis colonization is frequent in patients with chronic obstructive pulmonary disease (COPD) producing local and systemic inflammation. Heart failure is also a common comorbidity among patients with COPD. Heart failure is a chronic, frequent, and disabling condition with high morbidity and mortality, but with a modifiable course where endothelial dysfunction and pulmonary arterial hypertension have great importance. Animal models have shown that Pneumocystis infection can cause relevant functionally changes in vascular responses in the lung, promoting the development of pulmonary hypertension. Pneumocystis colonization could be a hidden cause of worsening heart failure through it capacity to induce inflammatory response with subsequent endothelial dysfunction and pulmonary hypertension. The aim of the present study was to investigate the prevalence of Pneumocystis jirovecii colonization in heart failure patients and its possible association with reduced or preserved ejection fraction.

Methods: A cross-sectional study was carried out including 36 heart failure patients and 36 control cases. Identification of P. jirovecii colonization was performed by means of molecular techniques in oropharyngeal washing.

Results:Pneumocystis-DNA was identified in oropharyngeal washing in 1 (2.7%) of 36 heart failure patients and in 3 (8.3%) of 36 controls.

Conclusions:Pneumocystis colonization does not seem to have a role in the pathophysiology of heart failure.