Etiological analysis of two necrotizing pneumonia cases

Abstract

Objective To analyze the clinical features and etiology characteristics of two cases of necrotizing pneumonia. Methods The clinical features, diagnosis and treatment process of the two patients were summarized. Drug sensitivity test of the Staphyloccocus aureus separated from the blood culture was performed. RT-PCR and next-generation sequencing were used to analyze lower respiratory tract secretion samples to identify the pathogens causing respiratory infections in the two patients. Results The two patients showed acute onset, rapid deterioration and severe lung damage. Both patients died within a short time despite active treatment. Methicillin sensitive S. aureus (MSSA) was identified from one patient by blood culture, sputum culture and drug sensitivity test. For both patients, the influenza B virus nucleic acids in lower respiratory tract secretion samples were positive and the results of next-generation sequencing indicated MSSA positive. Virulence gene test showed that the strains were carrying the gene of Panton-Valentine leukocidin (PVL). Conclusions Both patients with necrotizing pneumonia were co-infected with PVL-positive MSSA and influenza B virus. Necrotizing pneumonia caused by PVL-positive MSSA should be cautioned during influenza season. Key words: Influenza B; Staphylococcus aureus; Necrotizing pneumonia; Panton-Valentine leukocidin