[Role of glucocorticoids in pneumocystis pneumonia in patients with non-HIV infection/AIDS (HIV/AIDS) and related mechanisms].

Pneumocystis pneumonia (PCP) is an opportunistic infection caused by Pneumocystis carinii and is the most common fungal infection in HIV/AIDS patients. With the routine use of antiretroviral therapy (ART), the incidence of PCP infection in HIV/AIDS patients has decreased and the prognosis has improved significantly. On the other hand, the use of chemoradiotherapy and immunotherapy in patients with cancer, post-transplantation and autoimmune diseases are increasing dramatically, which has led to a similar increase in the incidence of PCP in these non-HIV/AIDS patients. There is a global shift in research on PCP from HIV-infected co-infected PCP (HIV-PCP) to non-HIV-infected co-infected PCP. The clinical course of non-HIV-PCP is rapid and severe, and the morbidity and mortality rates are higher than those of HIV-PCP. Studies have shown that 90% of non-HIV-PCP patients have a history of glucocorticoid use prior to infection, such as in patients with hematologic malignancies, solid organ transplants, and rheumatic diseases, and that long-term high-dose glucocorticoid use is an important risk for PCP susceptibility. Clinical practice has shown that PCP often occurs during the tapering of glucocorticoids, and a higher proportion of patients develop diffuse pulmonary lesions and, in more severe cases suffer from life-threatening acute respiratory failure. The pathogenesis of non-HIV infections associated with PCP is not yet clarified, and there is a lack of effective therapeutic practices that require further investigation.肺孢子菌肺炎（PCP）是一种由肺孢子菌引起的、人类免疫缺陷病毒感染/获得性免疫缺陷综合征（HIV/AIDS）患者最常见的机会性真菌感染。随着抗逆转录病毒治疗（ART）的出现，HIV/AIDS患者罹患PCP感染的概率降低，且治疗效果明显改善。而另一方面PCP在肿瘤放化疗、免疫治疗、器官移植术后抗排异治疗和自身免疫性疾病治疗等因素所致免疫功能低下或免疫功能受损等非HIV/AIDS患者中越来越常见。全球范围内PCP的研究热点正在从HIV感染合并PCP（HIV-PCP）向非HIV-PCP转变。与HIV-PCP相比，非HIV-PCP临床进展迅速，病情严重，病死率也更高。研究显示90%的非HIV-PCP患者在感染前有糖皮质激素使用史，如在血液系统恶性肿瘤、实体器官移植和风湿病患者中，长期大剂量使用糖皮质激素是PCP易感的重要风险。临床观察发现，PCP经常发生在糖皮质激素减量过程中，发生PCP时，较高比例的患者会出现肺部弥漫性病变，严重者出现急性呼吸衰竭，危及患者生命。目前非HIV-PCP的发病机制尚未明确，也缺少有效的治疗措施，需要进一步研究。.