Bilateral bloody nipple discharge in a male infant: sonographic findings and proposed diagnostic approach.

Bloody nipple discharge is an uncommon finding in the pediatric population, without clear diagnostic and therapeutic guidelines established. We noted a case of a 3-month-old male infant who presented with bilateral blood-stained nipple discharge, with unremarkable medical history. Sonographic findings revealed bilaterally dilated ducts and cysts with mixed iso- and hypoechoic intraductal content. Possible causes of this condition include hyperlaxity syndrome with decreased function of elastic fibers and fibrocystic changes in breasts, and unusual response to maternal hormones, transferred to the neonate either transplacentally or through breastfeeding. Given the most probable benign etiology and self-limiting nature of the described condition, a conservative approach is suggested. Unnecessary invasive procedures should be avoided.