Severe pneumonia in Chinese patients with systemic lupus erythematosus

Objective This study aimed to investigate the clinical characteristics and risk factors associated with severe pneumonia in systemic lupus erythematosus (SLE) patients from China. Method We performed a retrospective study in 112 hospitalized SLE patients who had had pneumonia for 8 years. The primary outcome was severe pneumonia, followed by descriptive analysis, group comparison and bivariate analysis. Results A total of 28 SLE patients were diagnosed with severe pneumonia, with a ratio of 5:23 between men and women. The mean age at diagnosis was 44.36 +/- 12.389 years. The median disease duration was 72 months, and the median SLE Disease Activity Index 2000 (SLEDAI 2K) score was 8. The haematological system was the most affected, with an incidence of anaemia in 85.7% of cases and thrombocytopenia in 75% of cases, followed by lupus nephritis in 50% of cases and central nervous system involvement in 10.71% of cases. Cultured sputum specimens were positive in 17 (68%) SLE patients with severe pneumonia, of whom nine (36%) were cases of fungal infection, five (20%) were cases of bacterial infection and three (12%) were cases of mixed infection. Using multivariate logistic regression analysis, we concluded that a daily dosage of prednisone (>10 mg; odds ratio (OR) = 3.193, p = 0.005), a low percentage of CD4+ T lymphocytes (OR = 0.909, p = 0.000), a high SLEDAI 2K score (OR = 1.182, p = 0.001) and anaemia (OR = 1.182, p = 0.001) were all independent risk factors for pneumonia in SLE patients, while a low percentage of CD4+ T lymphocytes (OR = 0.908, p = 0.033), a daily dose of prednisone of >10 mg (OR = 35.67, p = 0.001) were independent risk factors for severe pneumonia in SLE patients. Conclusion Severe pneumonia is not rare in lupus, and is associated with high mortality and poor prognosis. Monitoring CD4+ T-cell counts and giving a small dose of glucocorticoids can reduce the occurrence of severe pneumonia and improve the prognosis of patients with lupus.