[Langerhans cell histiocytosis presenting as isolated adenitis in an infant: case report].

Langerhans cell histiocytosis in infants is a rare condition, and presentation as an isolated cervical adenitis is exceptional at this age. We describe the case of a 3-month-old female infant presenting with a neck mass in the right mandibular angle with poor response to antibiotic treatment. Fine needle aspiration was performed and confirmed the diagnosis of Langerhans cell histiocytosis with complementary tests showing no features of systemic involvement. Langerhans cell histiocytosis should be considered in the differential diagnosis of subacute neck masses with poor outcome in infants and physicians should consider performing a fine needle aspiration to establish the diagnosis.