Specific skin signs as a cutaneous marker of diabetes mellitus and the prediabetic state - a systematic review.

INTRODUCTION: Diabetes mellitus and the prediabetic state are associated with a number of skin manifestations. This study is a systematic review of the following manifestations: acanthosis nigricans (AN), skin tags (ST), diabetic dermopathy (DD), rubeosis faciei (RF), pruritus (PR), granuloma annulare (GA), necrobiosis lipoidica (NL), scleroedema diabeticorum (SD) and bullosis diabeticorum (BD). These conditions possibly relate to underlying diabetogenic mechanisms. Our aim was to determine whether skin signs are feasible as cutaneous markers for the prediabetic or diabetic state.

METHODS: Data were collected from the databases PubMed, Embase and Cochrane. Articles were excluded if the populations presented with comorbidities or received treatment with drugs affecting the skin. Also, animal studies, studies with poor methodology and pilot studies were excluded.

RESULTS: Among the 34 included original articles, an association with diabetes was shown as follows: in eight articles with AN, five articles with ST, three articles with GA, two articles with NL, PR and SD respectively and in one article with RF. Three papers indirectly showed an association of DD with diabetes. Association between bullous skin lesions and diabetes was only documented by case reports and case series.

CONCLUSION: The results indicate a benefit of diabetes screening in individuals presenting with AN, ST or BD. Further studies are required to enlighten a possible association with RF, GA, SD or NL. Until such studies are available, it is advisable to screen individuals with the skin lesions presented by measuring their glycated haemoglobin.