AIM: To study the different epidemiological features of patients with contact lens-related microbial keratitis(CLRMK)in Tanta University Hospital in Egypt in order to assess different aspects of that problem, improve patients' awareness and in a trial to find practical solutions.

METHODS: All cases with keratitis attending the Outpatient Clinic of Ophthalmology Department at Tanta University Hospital during a period of 5y starting from the first of January 2009 to the end of December 2013 were selected and carefully examined and cases with CLRMK were further examined and investigated.

RESULTS: Out of total 108 496 attendants during this period with different complaints, there were 1463(1.3%)cases suffering from different forms of keratitis and 151(0.1%)with CLRMK. Results revealed that CLRMK is common in age group <30y, more in students(49%), families with large number and large crowding index, rural than urban residence, patients with outdoor water sources and insanitary sewage disposal. From history taking, it was found that CLRMK was more common with overnight use, insanitary storage cases or solutions and unsafe sources like shops of cosmetics and hair dressers. Cultural results were positive in 92% and negative in 8% of cases. The positive culture results were mixed infection(bacterial and fungal)in most of cases(53, 35.1%), bacterial only(43, 28.5%), fungal only(31, 20.5%)and acathamebic in 12(8%)of cases.

CONCLUSION: CLRMK is more frequent in students, rural areas, in outdoor water supply, insanitary sewage disposal. Overnight use, insanitary storage cases or solutions and unsafe sources were associated with increased incidence of CLRMK.