Methyl Ethyl Ketone-Related Loss of Matrix With Nail Onycholysis and Pterygium (ME KLMNOP): Case Report of a New Etiology for Onycholysis and Pterygium.

Methyl ethyl ketone is an organic solvent commonly used in adhesives and paints. Overexposure to methyl ethyl ketone can irritate the central nervous system, eyes, and respiratory system. When in direct contact with skin, methyl ethyl ketone can lead to dryness and cracking of the skin. Forty years ago, methyl ethyl ketone was used in the Navy to degrease and remove paint from planes and naval equipment. A 57-year-old Navy veteran presented with an absence of all fingernails and thumbnails as well as pterygium formation on his digits; however, his toenails were normal. Additional history revealed that his unprotected hands were regularly exposed to methyl ethyl ketone for three years. His nails shed and stopped growing after one year of this work; subsequently, pterygiums developed. We postulate that exposure to methyl ethyl ketone may result in chemical destruction of the nail matrix in a similar manner to phenol or sodium hydroxide. We introduce the following acronym that describes not only the etiology but also the manifestations of Methyl Ethyl Ketone-related Loss of Matrix with Nail Onycholysis and Pterygium (ME KLMNOP).