Prognostic analysis of Pneumocystis jirovecii pneumonia in interstitial lung disease patients: a retrospective clinical study

Abstract

Background Pre-exiting chronic lung disease was a poor prognostic factor for pneumocystis jiroveci pneumonia (PJP). However, the clinical characteristics and the prognostic factors of HIV negative PJP patients (non-HIV-PJP) with interstitial lung disease (ILD) remains unclear. Methods This was a retrospective study of hospitalized patients with confirmed PJP and ILD at Peking Union Medical College Hospital between January 2014 and December 2020. The enrolled patients were stratified based on the presence or absence of ILD and the presence of fibrotic ILD (FILD) or nonfibrotic ILD (non-FILD). The log-rank test and Cox regression models were used to analyze the prognostic factors for PJP patients with different pre-existing statuses. Results Among 836 hospitalized individuals with PJP, there were 378 non-HIV-PJP with complete clinical-radiological-follow-up data. Among them, there were 133cases (35.2%) with non-HIV-ILD-PJP, and 70 patients were classified as fibrotic ILD-PJP. The all-cause mortality rate for ILD-PJP group was higher than that of non-ILD-PJP group (57.9% vs 38.4%, Log-rank = 12.2, p < 0.001, However, the all-cause mortality was similar between FILD-PJP and non-FILD-PJP (Log-rank = 0.03, p > 0.05). Co-infection with aspergillosis(HR = 2.89, χ2 = 5.0, p = 0.02, 95%CI:1.14–7.28), honeycomb in the chest HRCT(HR = 16.3, χ2 = 16.8, p < 0.001, 95%CI:4.3–62), invasive ventilation(HR = 3.02, χ2 = 7.1, p < 0.01, 95%CI:1.34–6.82) and non- invasive ventilation(HR = 6.2, χ2 = 16.7, p < 0.001, 95%CI:2.58–14.9 ) were independent survival risk factors for non-HIV-ILD-PJP. Non-invasive ventilation support (HR = 928.56, χ2 = 7.3, p < 0.01, 95%CI:6.6-130796.5) and the serum D-dimer (HR = 1.2, χ2 = 10.9, p < 0.001, 95%CI:1.01–1.34) were independent survival risk factors for fibrotic ILD-PJP patients. Conclusions Pre-exiting ILD is independently associated with poor survival of PJP patients. Co-infection with aspergillosis, honeycomb in the chest HRCT, invasive ventilation and non- invasive ventilation were independent survival risk factors for ILD patients complicated with PJP.