Characterization of Pneumocystis jirovecii pneumonia at three tertiary comprehensive hospitals in southern China

Abstract

Due to the increasing use of immunosuppressant therapy, Pneumocystis jirovecii pneumonia (PJP) has become an emerging concern in human immunodeficiency virus (HIV)-negative patients. In this study, we conducted a retrospective study of 96 hospitalized patients with PJP from January 2015 to June 2019 at three tertiary comprehensive hospitals in Southern China. Information was collected regarding patient demographics, clinical manifestations, risk factors, laboratory analyses, radiological images, and treatment outcomes. PJP infection was most commonly found in middle-aged men. Kidney diseases (35.5%) and connective tissue diseases (38.7%) were the predominant risk factors for PJP. About half of the patients (48.4%) received glucocorticoid, immunosuppressant, and/or chemotherapy in a low dose or in a short-term (< 3 months). None of the patients had previously received trimethoprim-sulfamethoxazole (TMP-SMX) for PJP prophylaxis. All patients had two or more clinical manifestations (cough, dyspnea, fever, and chest pain). Biochemical investigations of CRP, ESR, PaO₂, LDH, and KL-6 showed that over 90% of the patients exceeded the reference range of indicators. Our analyses revealed the dominant risk factors (HIV, kidney diseases, and connective tissue diseases) and the most consistent biochemical indicators (LDH, BG, and KL-6) for PJP. Moreover, early prophylaxis, diagnosis, and treatment should contribute to improve the survival of these PJP patients.

Keywords: HIV; Non-HIV-immunocompromised patients; Pneumocystis jirovecii; Pneumonia; Serologic biomarkers.

Fig. 1

P. jirovecii cysts show crowding in foamy alveolar casts in bronchoalveolar lavage fluid (GMS, × 1000). The cysts are thick-walled, round, and approximately 5–8 μm in size. Thin-walled cysts also exist but are less prominent. Cysts contain up to eight intracystic bodies. Precysts have also been described for this organism. The precysts are spherical, 4–7 μm in diameter, and do not contain intracystic bodies, but may contain one or more nuclei

Fig. 2

a Chest computed tomography showing bilateral diffuse ground-glass opacity (red arrow) in a 19-year-old male patient with systemic lupus erythematosus. b Chest computed tomography showing bilateral diffuse ground-glass opacity and patchy consolidations (blue arrow) in a 68-year-old male patient with nephrotic syndrome. c Chest computed tomography showing bilateral pulmonary consolidations (green arrow) in a 53-year-old male patient after renal transplantation

Fig. 3

Annual number of PJP cases in three tertiary comprehensive hospitals in Nanchang, Jiangxi, China. The percentages of HIV (red line) and non-HIV PJP patients (blue line) per year are shown between January 2015 and June 2019