Risk factors for Pneumocystis jirovecii Pneumonia (PCP)
It is estimated that up to 20% of adults might carry this fungus at any given time, without any symptoms, resulting in continuous interindividual circulation responsible for transmission to immunocompromised individuals who are at high risk of developing PCP. ⁽²⁾ A

mongst them, around 30-40% of PCP infections occur in individuals with human immunodeficiency virus (HIV) infection/acquired immune deficiency syndrome (AIDS). In addition to HIV coinfection, other risk factors include chronic lung diseases, cancer, inflammatory or autoimmune diseases and solid organ or stem cell transplant. ⁽²⁾

Pneumocystis jirovecii pneumonia (PCP) and COVID-19

Patients with coronavirus disease 19 (COVID-19) in the intensive care unit (ICU) frequently develop respiratory fungal infections. The most frequent diseases are COVID-19 associated pulmonary aspergillosis (CAPA), COVID-19 associated pulmonary mucormycosis (CAPM) and the Pneumocystis jirovecii pneumonia (PCP), with the latter being more common in patients with both COVID-19 and underlying HIV infection. ^(3,4) However, a recent review reported a similar mortality rate between the HIV and non-HIV group in COVID-19 patients with Pneumocystis jirovecii coinfection, with an overall mortality rate of 41.6%. ⁽⁵⁾

<sup>References
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5. Chong, W.H., Saha, B.K. & Chopra, A. Narrative review of the relationship between COVID-19 and PJP: does it represent coinfection or colonization?. Infection 49, 1079–1090 (2021). https://doi.org/10.1007/s15010-021-01630-9
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7. Mercier T, Guldentops E, Patteet S, Beuselinck K, Lagrou K, Maertens J. Beta-d-Glucan for Diagnosing Pneumocystis Pneumonia: a Direct Comparison between the Wako β-Glucan Assay and the Fungitell Assay. J Clin Microbiol. 2019 May 24;57(6):e00322-19. doi: 10.1128/JCM.00322-19. PMID: 30918045; PMCID: PMC6535610.</sup>