Introduction: Langerhans cell histiocytosis (LCH) is characterized
by clonal proliferation of immature dendritic cell precursors that
infiltrate several organs. The median age of diagnosis in childhood is
three years old and can simulate common childhood dermatoses. We
present a case report of LCH with initial cutaneous manifestation and
subsequent severe multisystemic presentation. Case report: Male, one
year and seven months old, previously healthy, had erythematous, scaly
and itchy lesions in the scalp, eyebrow and cervical region, in addition
to inguinal erythema. The patient was treated as seborrheic dermatitis
and diaper eczema, without improvement. Subsequently new signs
appeared: subungual hyperkeratosis, petechiae in palms and plants, fever,
jaundice and otorrhagia. HCL hypothesis was confirmed by histological
analysis. Propaedeutic extension showed otorhinolaryngological
involvement, affected bones, hematopoietic abnormalities, pulmonary
and hepatobiliary involvement. Despite chemotherapy treatment, there
was progression to liver failure, infection and death. Discussion: The
cutaneous manifestations in LCH include pruritic papules, plaques
and erythematous nodules on the scalp, diaper area and armpits. They
can mimic common early childhood dermatoses such as seborrheic
dermatitis, diaper dermatitis, herpetiform dermatitis and scabies, and
skin biopsy with immunohistochemistry are essential in cases with
progression despite of optimized therapy. Conclusion: Isolated skin
involvement in LCH generally indicates a better prognosis, however, the
possibility of severe systemic involvement justifies rigorous monitoring.
Early recognition and treatment are essential for a better prognosis,
and should be remembered as a differential diagnosis in childhood
dermatoses
