Question 1 of 4

A 40-year-old homeless alcoholic man presents to the ED complaining of foot numbness. He has been sleeping in a drainage culvert to stay out of the wind. Nighttime temperatures have been well above freezing, but it has rained steadily for the past 5 days. His feet are pale and numb. They develop severe burning pain on rewarming. What is the most likely diagnosis?


Cold urticaria


Trench foot


Trench foot occurs when feet are exposed to cold and wet conditions, but not freezing. It is most often seen in military situations. Frostbite is an injury due to freezing that could superficially resemble trench foot. Chilblains are inflammatory lesions that typically occur on the hands of women after cold exposure. Cold urticaria is a hypersensitivity reaction to cold temperatures. Panniculitis involves necrosis of subcutaneous fat due to prolonged cold, but not freezing temperatures, and occurs mainly in children and the thighs and buttocks of women horseback riders.