infection should be considered Breast development in prepubertal girls, without other signs of puberty, particularly in those younger than years of age, is likely due to the common and benign condition of premature thelarche Since this may be the first sign of precocious puberty, urgent follow-up with the primary care physician and/or an endocrinologist for additional testing is recommended Among prepubertal children, isolated lesions underneath the nipple also may be noted and are usually benign cysts Pubertal/Postpubertal Male The adolescent male ( Fig 16.2 ) may complain of breast pain without evidence of clearly palpable breast enlargement This sensation may be caused by minor chest trauma in a boy with early pubertal gynecomastia or may represent underlying chest pain (see Chapter 55 Pain: Chest ) Most often, adolescent males will present for bilateral (sometimes asymmetric) enlargement diffusely throughout the breast tissue, which usually represents (physiologic) pubertal gynecomastia, in the setting of normal sexual development Unilateral, discrete masses or bilateral, diffuse enlargement with abnormal sexual development require subspecialty referral and additional diagnostic evaluation Pubertal/Postpubertal Female The initial step in evaluating the adolescent girl ( Fig 16.3 ) is to obtain a pregnancy test, which, when positive, points to a number of conditions that are specific to the gravid state (see earlier discussion) Both pregnant and nonpregnant girls may experience a myriad of disorders related to the breast The emergency physician’s primary goal is to distinguish underlying disorders that are causing chest rather than breast pain (see Chapter 55 Pain: Chest ) and to assess for a few relatively minor problems, including cellulitis, abscess, hematoma, and traumatic erosions In cases where there is concern for deeper infection or an irregular or large breast mass, breast ultrasonography can be used to rule out severe, life-threatening etiologies Less severe causes of breast enlargement, masses, and discharge require outpatient follow-up and evaluation by an appropriate specialist