[Perianal leukemic infiltration. Case report].
BACKGROUND: Leukemic infiltration of perianal skin (leukemia cutis) is quite uncommon, and may consist of no diffuse infiltration, erythema, ulceration, fistula, and abscess. Diagnosis may be established by biopsy and adequate hematologic studies. Treatment must be conservative in patients with poorly controlled disease (sitz baths, antibiotics, radiotherapy), and surgical in patients with risk of fulminant sepsis and death. OBJECTIVE: To report a case of leukemic perianal infiltration with atypical ulcerated lesion. CASE REPORT: Female patient, 21 years of age with diagnosis of AML M7, began with perianal pain posterior to evacuation associated with bleeding; at perianal examination we found anterior atypical ulcerated lesion. We carried out a biopsy under suspicion of leukemic infiltration corroborated by histopathology. The patient received conservative treatment. CONCLUSIONS: We must suspect leukemic infiltration in patients with anal symptoms and effect close surveillance. Prognosis depends on control of hematologic disease.