Methamphetamine Keratitis as a Variant of Neurotrophic Ocular Surface Disease

Abstract

Abstract: : Purpose:Methamphetamine keratitis (MAK) represents a pernicious corneal disease characterized by repeated attacks of bilateral inferiorly located virulent if not polymicrobial corneal ulcers. These infections often prove resistant to even the most aggressive medical therapy, progressing to stromal lysis, perforation, and ultimate loss of the eye. Multiple theories have been advanced to explain the highly–destructive nature of MAK, including neurotrophic keratitis (NTK), but no theories have been proven to date. The purpose of this report is to document for the first time, through quantitated corneal sensation, coexistent NTK in a case of MAK. Methods:Observational case report. Results:A 36–year–old homeless male with an admitted recent history of methamphetamine abuse was admitted for treatment of a severe pseudomonas corneal ulcer OS. His past ocular history was significant for 20 years of soft contact lens wear OU, and recent hospital admission for treatment of bilateral pseudomonas keratitis. Slit–lamp exam revealed multiple paracentral corneal scars OD, and an approximate 6 mm x 6 mm inferocentral full–thickness stromal infiltrate OS with impending descemetocele. Quantitated corneal sensation (Cochet–Bonnet esthesiometer) tested at noninvolved central and paracentral sites was 22.5 mm OD and 0.0 mm OS (normal 45 mm+). Conclusions:This patient, in quantitated fashion, for the first time clearly identifies NTK as an associated condition in an active MAK case. This observation provides a ready explanation for the highly–destructive nature of this desease, whereby secondary opportunistic microbial infections complicate a systemic and therefore bilateral drug–generated neurotrophic ocular surface disease process.

Keywords: keratitis • cornea: clinical science • drug toxicity/drug effects