Anterolateral Leg Alopecia: Unknown Entity or Underreported?

The document reports a case of anterolateral leg alopecia, a condition characterized by well-circumscribed, symmetrical hair loss on the anterior and lateral aspects of the lower legs, with an estimated prevalence of up to 35% in males. A 35-year-old man with no family history of hair loss or autoimmune disorders, but with male pattern baldness and chronic inflammatory demyelinating polyneuropathy, presented with non-progressive hair loss on his lower legs. Examination and skin biopsy confirmed the diagnosis of anterolateral leg alopecia, showing thinned epidermis and reduced hair follicular units without any other abnormalities. The patient was informed about the benign nature of the condition and no treatment was given. The document discusses the lack of sufficient evidence for the various hypotheses regarding the cause of this condition, such as friction or autoimmune etiology, and notes that it is benign, nonprogressive, and may resolve spontaneously. The case highlights the need for more documentation and histopathological examination to differentiate anterolateral leg alopecia from other conditions like alopecia areata and to better understand its etiopathology.