RESUMEN
Thallium poisoning is usually accidental. We present a case of a 51-year-old woman who was evaluated in June 2018 for myalgia, vertigo, asthenia, and abdominal pain. Physical examination revealed temporal-spatial disorientation, jaundice, and asterixis. The laboratory reported the following: bilirubin, 10.3 mg/dL; aspartate transaminase, 78 U/L; alanine transaminase, 194 U/L; albumin, 2.3 g/dL; prothrombin time, 40%; and platelet count, 60,000/mm3. Serology performed for hepatitis A, B, and C; Epstein-Barr virus; cytomegalovirus; and human immunodeficiency virus was negative, and a collagenogram was negative. Physical reevaluation revealed alopecia on the scalp, armpits, and eyebrows; macules on the face; plantar hyperkeratosis; and ulcers on the lower limbs. Tests for lead, arsenic, copper, and mercury were carried out, which were normal; however, elevated urinary thallium (540 µg/g; range, 0.4-10 µg/g) was observed. The patient was treated with á´ -penicillamine 1,000 mg/day and recovered her urinary thallium levels were within normal range at annual follow-up. Thallium poisoning is extremely rare and can be fatal in small doses. An adequate clinical approach can facilitate early diagnosis.