Influence of environmental temperature on the occurrence of non-necrotizing cellulitis of the leg SIR, Non-necrotizing cellulitis of the leg is a common cutaneous bacterial infection whose risk factors include venous insufficiency, lymphoedema and toe-web intertrigo. The role of environmental temperature remains controversial. 1 To study the relationship between environmental temperature and the frequency of non-necrotizing cellulitis of the leg, we reviewed all patients hospitalized with nonnecrotizing cellulitis of the leg in a university hospital in a temperate region of France during a 4-year period, and correlated findings with the local environmental temperature during the same period.Patients included in this study were consecutive patients referred for non-necrotizing cellulitis of the leg from January 1995 to December 1998 in the Departments of Dermatology, Internal Medicine and Infectious Diseases of the Rouen University Hospital. The diagnosis of cellulitis of the leg was retrospectively identified using the database of the Medical Information System. The mean and maximum temperatures of each the 8 days prior to the date of hospital admission were obtained from the local meteorological unit for each case. Correlations between the mean and maximum daily temperature of each day from day ) 8 to the admission day (lag 0-8 days) and the daily number of patients hospitalized for cellulitis of the leg were studied using a nonparametric Poisson regression model to adjust for time trends and days of the week (generalized additive model). 2 Eight hundred and ninety-eight patients with cellulitis of the leg [342 men (38%) and 556 women (62%)] were