Ma JG, et al. - Researchers compared epidemiology, clinical features, and microbiology of 3 types of deep sternal wound infection (DSWI), a known severe complication following cardiac surgery. Also, they examined the antibiotic resistance in DSWI patients. They noted that epidemiology and clinical features varied between 3 types of DSWI. The most common pathogens in DSWI patients were P. aeruginosa and S. aureus. Antibiotic resistance was recognized as a serious concern. Therefore, prevention and treatment of DSWI should be closely tailored to clinical features, local microbiological characteristics, and resistance patterns of commonly encountered pathogens.

• For this study, a total of 170 adult post-cardiac surgery DSWI patients were recruited from 2011 to 2015.
• These patients underwent the pectoralis major muscle ap transposition in researchers' department.

• Type II DSWI was detected in the majority (99 patients, 58.2%) of patients out of a total of 170 adult patients with DSWI (mean age of 54 years).
• Signicant differences were noted between the 3 types of DSWI patients in terms of gender, smoking history, chronic obstructive pulmonary disease (COPD), length of intensive care unit (ICU) stay, and hospitalization cost (P<0.05).
• Fever and wound dehiscence accompanied by purulent secretions were documented as the most common symptoms of DSWI patients.
• More frequent association of types I and II DSWI with hypoproteinemia and high leucocyte count (P<0.05) was reported.
• Microbiological diagnosis was available for 77 of 170 patients (45.3%).
• A total of 157 pathogens were detected; of these, 87 (55.4%) species of gram negative bacilli were identified and most commonly were Pseudomonas aeruginosa (25.5%) and methicillin-susceptible Staphylococcus aureus (20.4%).
• However, researchers found no statistically significant microbiological differences among the 3 DSWI types (P>0.05).
• Notably, 100% resistance to cefazolin and cefuroxime was shown by P. aeruginosa isolates.
• Meanwhile, it was noted that the resistance rate of Acinetobacter baumannii isolates to commonly used antibiotics was greater than 70%, while resistance rates of staphylococcus to penicillin-G were 100% and to clindamycin were over 70%.
• Findings demonstrated that no isolates were resistant to vancomycin, linezolid, and tigecycline.