Microbial etiology, susceptibility profile of postradiation nasopharyngeal necrosis patients with nasopharyngeal carcinoma.

Abstract Objective Postradiation nasopharyngeal necrosis (PRNN) is a notorious complication after radiotherapy that affects prognosis in patients with nasopharyngeal carcinoma (NPC). It is important for clinical doctors to realize this problem in order to cope with this severe clinical situation. The aim of our study was to assess the bacteriology of PRNN and to demonstrate the antimicrobial susceptibility pattern that should guide the clinicians towards more appropriate antibiotic use. Methods Sixty-nine NPC patients with PRNN in our department between March 2013 and December 2017 were retrospectively enrolled. Pathogenic culture and drug sensitivity test were performed in these 69 NPC patients with PRNN. The infection rate of Pathogens and the sensitivity of the drugs were analyzed based on these results. Results Sixty-nine NPC patients with PRNN were enrolled in our study. Pathogens were identified in 58 (84%) patients. Of the 58 patients, Staphylococcus aureus was isolated in 34 (58.6%) patients. And the second most common group of bacterial isolates was Pseudomonas aeruginosa. Antibiotic sensitivity showed that Levofloxacin was the highest (88.5%), followed by Ciprofloxacin (85.2%) and Gentamicin (80.3%). The only pathologic fungus was Candida albicans, about 6.8%. The positive rates of bacterial and fungal culture in PRNN patients were not significantly different from the patients’ gender, age, stage, number of radiotherapy courses (P > 0.05), but the cure rate was statistically higher in culture-negative patients in comparison with culture-positive patients (63.6% vs 20.7%, P = 0.011). Conclusion Our results provide an overall picture of the microbiology and drug susceptibility patterns for NPC patients with PRNN and could help implement guidelines for more rational treatment and improve therapeutic outcome.