Diverse cutaneous manifestation of Langerhans cell histiocytosis: a 10-year retrospective cohort study.

Cutaneous manifestation is a common presentation of LCH and is usually a leading clue for the disease diagnosis. Having cutaneous lesions did not show a significantly early age onset at diagnosis compared to those without skin lesions, P value = 0.71. In the present study, cutaneous findings were found as 77.7%. Seborrheic dermatitis-like lesions were the most common cutaneous type (42.8%), followed by papules/nodules/masses (28.5%), petechiae/hemorrhagic lesions (17.8%), and eczematous lesions (10.7%). Time to diagnosis of LCH presented with seborrheic dermatitis-like lesions was significantly longer than other cutaneous presentations, P value = 0.0011.Conclusion: Patients with LCH who had the manifestations of seborrheic dermatitis-like lesions can have diagnosis delayed due to the difficulty in distinguishing these lesions from normal seborrheic dermatitis lesions. Petechiae/hemorrhagic cutaneous signs in addition to the normal seborrheic dermatitis is the clue for early detection of the disease. To improve early detection of LCH, general pediatricians should be alerted to be aware of these skin symptoms, and if they persist, a dermatologist, pediatric if available, should be immediately consulted. What is Known? • Cutaneous manifestation is a common presentation of LCH and is usually a leading clue for the disease diagnosis. What is New? • Patients with LCH who have the manifestations of seborrheic dermatitis-like lesions can have a delayed diagnosis due to the difficulty in distinguishing normal from seborrheic dermatitis lesions. • Petechiae/hemorrhagic cutaneous signs in addition to the normal seborrheic dermatitis are the clue to the early disease detection.