Modified Crosslinking Protocole For Rebellious Keratitis : A Review Through 2 Cases

Infectious keratitis is one of the most common causes of ocular morbidity and blindness worldwide. They can have a bacterial, fungal, amoebic or viral origin. The visual prognosis depends on the initiation of antimicrobial treatment without delay Faced with the emergence of multi-resistant bacteria and the difficulty in treating other germs, other alternatives are needed. Corneal collagen cross-linking (CXL) is first indicated as a treatment for progressive keratoconus. With hindsight, modifications to the protocol allow the broadening of its field of interest to include resistant corneal infections.We report here two serious corneal abscesses with good evolution after crosslinking.

Department of ophthalmology, Mohammed VI university Hospital , Oujda , Morocco

Here we report 2 cases of resistant keratitis , treated with a modified CxL keratitis protocole, with good evolution.

- 35-year-old patient, followed for keratoconus, adapted by contact lenses, with visually impaired left eye. Examination VA at HM in RE, total abscess of the cornea. 1st line treatement :  fortified eyedrops: ceftazidime and vancomycin, corneal prelevement:  Klebsiella spp, sensitive to chloramphenicol. topical chloramphenicol didn't lead to significant improvement. CxL with marked improvement with BVCA to 2/10.
-20-year-old patient,  keratoconus , scleral lenses, VA of 10/10, with painful redeye. VA 1/10 , abscessed central ulcer . Put on : ceftazidime and vancomycin. Then, CF fluconazole with partial improvement. patient then benefited from a CxL l, with healing of her abscess and recovery of her BCVA.

1. CXL has been shown to be an effective treatment for early bacterial infectious keratitis over a 10-year period with a very good cure rate against bacteria (average 88%) as reported in a meta. -recent analysis and most clinical trials report successful treatment rate when using PACK-CXL in combination with standard antibiotic therapy.
2. The combined effect of UV-A light and riboflavin was found to be greater than their separate effect, with a 10-fold increase in cytotoxicity compared to UV-A alone. 
3. In a systematic review in 2018 by Atia et al, a modification of the protocol of PACK-CXL could increase its effectiveness.
   
4. This procedure would be an intermediate step before keratoplasty, difficult in settings with a lack of corneal grafts.