Vol. 11, Issue 12 (2022)

Author(s):
Dr. Pruthvishree BS, Dr. Bhoj Raj Singh, Dr. Ravikant Agrawal and Dr. Dharmendra Kumar Sinha

Abstract:
NSAIDs and steroids are non-antibiotic drugs which may exhibit antibacterial activity when used in combination with antibiotics. The present study was designed to assess thein-vitro interaction of ketoprofen, meloxicam (NSAIDs) and betamethasone (steroid)with enrofloxacin and doxycycline in E. coli and S. aureus. Methods-The minimum inhibitory concentration (MIC) of ketoprofen, meloxicam, betamethasone, enrofloxacin and doxycyclinewas determined forE. coli and S. aureus isolates by micro-broth dilution method. The combination effect was estimated by calculating the fractional inhibitory concentration index (FICI). Results-The minimum inhibitory concentration (MIC)of enrofloxacin for E. coliranged from 2 µg/ml to 32 µg/ml,and of doxycycline 32 µg/ml to 64 µg/ml. The MICof enrofloxacin and doxycycline resistant E. coli isolates stood constant at128 µg/ml for ketoprofen, 125 µg/ml of meloxicam,125 µg/mlof betamethasone, respectively. The MIC of enrofloxacinfor S. aureus ranged from 1 µg/ml to 128 µg/ml, and of doxycycline 0.25 µg/ml to 128 µg/ml. The MIC of ketoprofen, meloxicam and betamethasone for S. aureus ranged from 128 µg/ml to 512 µg/ml, 125 µg/ml to 500 µg /ml,and 125 µg/ml to 500 µg/ml, respectively. The enrofloxacin resistant E. coli isolates showed partial synergy (33%), additive (56.6%) and indifferent effect (10%) when enrofloxacin was used in combination with any of the three chosen non-antibiotics (ketoprofen, meloxicam and betamethasone). The combination effect of enrofloxacin with ketoprofen, meloxicam, and betamethasone were either indifferent (87%) or partial synergy (13%) for enrofloxacin resistant S. aureus isolates. About 96% of the doxycycline resistant E. coli and S. aureus isolates showed indifferent effect and 4% of the doxycycline resistant E. coli and S. aureus isolates showed partial synergy when doxycycline was used in combination with any of the chosen non-antibiotics (ketoprofen, meloxicam and betamethasone).The difference in interaction of NSAIDs and steroid with enrofloxacin and doxycycline among two bacteria indicated that mechanism of interaction may be bacteria specific and needs more elaborate studies.