title: Presence of the Panton-Valentine Leukocidin Genes in Methicillin-Resistant Staphylococcus aureus Is Associated with Severity and Clinical Outcome of Hospital-Acquired Pneumonia in a Single Center Study in China.
abstract: The Panton-Valentine leukocidin (PVL) genes of methicillin-resistant Staphylococcus aureus (MRSA) have previously been associated with severe infections. Here, the impact of the PVL genes on severity of disease and clinical outcome of patients with hospital-acquired pneumonia (HAP) or ventilator-associated pneumonia (VAP) due to MRSA was investigated in a single center observational study in a hospital in China. HAP due to MRSA was diagnosed in 100 patients and 13 of the patients were PVL positive, while VAP was diagnosed in 5 patients and 2 were PVL positive. The PVL positive patient group showed a significantly higher Acute Physiology and Chronic Health Evaluation (APACHE) II score (14.3 ±7.8 vs. 10.1 ±4.7, P = 0.005) and significantly more patients with CRP levels >80 mg/L (8/15 vs. 12/90, P = 0.006) or WBC counts >15x109/L (7/15 vs. 12/90, P = 0.006), indicating that the severity of disease is affected by the presence of the PVL genes. The outcome of the study was defined by 30-day mortality. Four (27%) of the PVL positive patients and four (4%) of the PVL negative patients died within 30 days (P = 0.01, Fisher exact test). Kaplan-Meier survival curves were generated for the PVL positive and PVL negative patient groups, which differed significantly (P = 0.003). Among the patients that died, the mean interval between diagnosis and death was shorter for the PVL positive patients (9.3 ±5.6 vs. 40.8 ±6.6 days, P = 0.013). Further analysis within the HAP and VAP patient groups showed that the presence of PVL in MRSA impacted the severity of disease and clinical outcome of HAP, but for VAP the number of patients included in the study was too low. In conclusion, in this single center study in a Chinese hospital the presence of the PVL genes in MRSA impacted the severity of disease and clinical outcome in patients with HAP due to MRSA.
authors.affiliation: Clinical Laboratory, Zhejiang Xiaoshan Hospital, Hangzhou, China.
authors.forename: Chuanling
authors.initials: C
authors.lastname: Zhang
authors.affiliation: Intensive Care Unit, Zhejiang Xiaoshan Hospital, Hangzhou, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Guo
authors.affiliation: Clinical Laboratory, Zhejiang Xiaoshan Hospital, Hangzhou, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Chu
authors.affiliation: Clinical Laboratory, Zhejiang Xiaoshan Hospital, Hangzhou, China.
authors.forename: Limeng
authors.initials: L
authors.lastname: Shen
authors.affiliation: Clinical Laboratory, Zhejiang Xiaoshan Hospital, Hangzhou, China.
authors.forename: Yuanyu
authors.initials: Y
authors.lastname: Guo
authors.affiliation: Clinical Laboratory, Zhejiang Xiaoshan Hospital, Hangzhou, China.
authors.forename: Huali
authors.initials: H
authors.lastname: Dong
authors.affiliation: Clinical Laboratory, Zhejiang Xiaoshan Hospital, Hangzhou, China.
authors.forename: Jianfeng
authors.initials: J
authors.lastname: Mao
authors.affiliation: Department of Microbiology and Parasitology, Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases, School of Medicine, Zhejiang University, Hangzhou, China.
authors.forename: Stijn
authors.initials: S
authors.lastname: van der Veen
mesh_terms: D000368:Aged; D001427:Bacterial Toxins / Q000235:genetics*; D002681:China; D003428:Cross Infection / Q000382:microbiology* / Q000473:pathology; D005098:Exotoxins / Q000235:genetics*; D005260:Female; D005798:Genes, Bacterial; D006801:Humans; D007956:Leukocidins / Q000235:genetics*; D008297:Male; D055624:Methicillin-Resistant Staphylococcus aureus / Q000235:genetics*; D008875:Middle Aged; D017720:Molecular Epidemiology; D012720:Severity of Illness Index
chemical_list: D001427:Bacterial Toxins; D005098:Exotoxins; D007956:Leukocidins; C078284:Panton-Valentine leukocidin