Borrelia Lymphocytoma Mimicking Butterfly Rash in a Pediatric Patient.

A 5-year-old girl presented with a facial butterfly rash that persisted for 5 months without arthralgia, fever, malaise, photosensitivity, or other symptoms. Lupus erythematosus was clinically suspected. All blood tests were negative or within normal values. Skin biopsy showed a dense nodular superficial and deep inflammatory infiltrate of lymphocytes that reaches subcutaneous tissue. The most striking histopathological finding was plasma cells with some perifollicular accentuation. Borrelia polymerase chain reaction assay of the tissue was positive, and we made the diagnoses of borrelia lymphocytoma mimicking butterfly rash of lupus erythematosus. The lesions disappeared with amoxicillin followed by cefuroxime for 28 days. In children, a variety of diseases including lupus erythematous may lead to a butterfly rash that is usually short lasting and commonly associated with systemic symptoms. Borreliosis may be related with long-lasting facial erythema in children and may mimic lupus and present high titers of antinuclear antibodies. In any case, borrelial lymphocytoma has not been previously reported as a cause of butterfly rash, thus mimicking acute lupus in a child, as in our case. From a histopathological point of view, the presence of plasma cells in a pseudolymphomatous infiltrate is a clue for the right diagnosis. Therefore, we suggest that borrelia serology should be done in children with butterfly rash lasting more than a month and empirical antibiotic treatment should be tried even in cases with negative serology.