Diagnosis and treatment of Pneumocystis jirovecii pneumonia in HIV-infected or non-HIV-infected patients-difficulties in diagnosis and adverse effects of trimethoprim-sulfamethoxazole.

The clinical characteristics of Pneumocystis jirovecii pneumonia (PCP) in patients with immunodeficiency virus (HIV) infection (HIV-PCP) differ from those in patients without HIV infection (non-HIV-PCP). We analyzed 31 adult HIV-PCP cases and 44 non-HIV-PCP cases between 2008 and 2018. The symptomatic period before the diagnosis was shorter in non-HIV-PCP (5 [3-8] days vs. 29 [14-55] days, P < 0.001) and the overall survival rate was lower in the non-HIV-PCP group (P = 0.022). Serum β-D glucan positivity (72.7% vs. 93.5%, P = 0.034) and Grocott stain positivity for Pneumocystis jirovecii in the bronchoalveolar lavage fluid (4.3% vs. 73.3%, P < 0.001) were significantly lower in the non-HIV-PCP group. This difficulty in laboratory diagnosis possibly resulted in the administration of concurrent antibiotics such as quinolones and macrolides (56.8% vs. 19.4% P = 0.002) in the non-HIV-PCP group. The adverse effects due to trimethoprim-sulfamethoxazole were more frequently observed in HIV-PCP (86.2% vs. 35.3%, P < 0.001). The duration of discontinuation of trimethoprim-sulfamethoxazole was 11 [8-14.5] days in HIV-PCP cases. Co-administration of adjunctive corticosteroid therapy did not mitigate hypersensitivity to trimethoprim-sulfamethoxazole. Our analysis indicated that the characteristics of PCP in patients with or without HIV was quite different. HIV-positive patients with PCP should be monitored closely to avoid adverse effects due to trimethoprim-sulfamethoxazole. Because positivity polymerase chain reaction test for P. jirovecii remained high (91.7%), it is suggested that bronchofiberscopy is warranted for diagnosis of PCP in HIV-negative patients.