Secretion of radioactivity in breast milk after Tc-99m DTPA aerosol and Tc-99m MAA lung imaging.

Abstract

Fifteen days after giving birth, a 30-year-old woman had the sudden onset of shortness of breath, cough, and paroxysmal nocturnal dyspnea. She underwent Tc-99m DTPA aerosol ventilation and Tc-99m MAA perfusion lung studies within a 24-hour interval. The patient had bilateral venous enlargement of the lower extremities, a history of recurrent pulmonary embolism, and had smoked cigarettes for 12 years until 1 year earlier. Despite its rare occurrence during pregnancy and the post-partum period, deep vein thrombosis complicated with pulmonary embolism remains the leading source of maternal death and complications. Both perfusion and ventilation scans revealed considerable activity in the breasts as a result of radioactivity in breast milk after the administration of Tc-99m-labeled radiopharmaceuticals. The total effective dose to the infant was less than 1 mSv because breast-feeding had been interrupted for 24 hours and 4 hours after the administration of Tc-99m MAA and DTPA, respectively.