Successful use of intravitreal and systemic colistin in treating multidrug resistant Pseudomonas aeruginosa post-operative endophthalmitis

We report a case series of post-operative endophthalmitis due to Pseudomonas aeruginosa. A total of 8 patients operated for cataract, were referred to our facility with acute onset of decreased vision 1-2 days following surgery. All patients had clinical evidence of acute exogenous endophthalmitis with severe anterior chamber exudative reaction. Ocular samples (aqueous aspirate and vitreous tap) for microbiology were taken from all eyes. Microbiology from all revealed P. aeruginosa which was resistant to all antibiotics except colistin. With prompt and accurate microbiological support it was possible to control the infection in all the eyes with the use of colistin intravitreally and intravenously which to the best of our knowledge, has been never reported. Intravitreal injection of colistin could be an option effective in the management of multi-drug-resistant endophthalmitis caused by Gram-negative bacteria.