Patient 1

A boy who was 4 years 5 months old presented with gynecomastia of apparently 2 to 3 weeks' duration. He had no exposure to any known exogenous form of estrogens (ingestants, salves, or ointments). His height and weight were at the 97th percentile and between the 75th and 90th percentiles, respectively. He had bilateral gynecomastia with firm, nontender breast tissue measuring 2 cm by 2 cm in diameter. His testes were 3 ml in volume and of normal consistency. His genitalia were prepubertal (Tanner stage 1). Laboratory investigation showed normal thyroid function; the follicle-stimulating hormone (FSH) concentration was 1.04 IU per liter (reference range, 0.25 to 1.92), luteinizing hormone 0.47 IU per liter (reference range, 0.02 to 1.03), testosterone 0.08 ng per milliliter (0.27 nmol per liter) (reference range, 0.02 to 0.25 ng per milliliter), estradiol less than 20 pg per milliliter (73 pmol per liter) (normal value, <20), dehydroepiandrosterone (DHEA) sulfate less than 5.0 μg per deciliter (0.14 μmol per liter) (reference range, 1 to 40), 17-alpha-hydroxyprogesterone 0.32 μg per liter (0.97 nmol per liter) (reference range, 0.2 to 0.8), and prolactin 8.0 μg per liter per liter (reference range, 2 to 29); the serum biochemistry values, including liver-function tests, were normal. On evaluation 3 months later, the breast buds were tender to palpation and had increased to 2.5 cm by 2.5 cm in diameter with an increased breast mound. The patient's mother reported applying a compounded “healing balm” containing lavender oil to his skin starting shortly before the initial presentation. The gynecomastia partially resolved within 4 months after application of the healing balm was discontinued, at which time the breast buds measured 1.5 cm by 1.5 cm in diameter and were soft in consistency. Several months later, his pediatrician stated that the gynecomastia had resolved completely.

Patient 2

A boy who was 10 years 1 month old presented with a 5-month history of gynecomastia. He and his mother reported that the condition seemed more prominent in the evening and a little less so in the morning. His medical history and family history were unremarkable. His height and weight were above the 97th percentile, and his body-mass index (the weight in kilograms divided by the square of the height in meters) was 21.1. He had firm, tender breast buds, measuring 3.5 cm by 4.0 cm in length and width and approximately 3.5 cm in depth, with stretching of the areolae. His testes were 3 ml in volume and of normal consistency. His pubic hair was Tanner stage 2 (a small amount of long hair at the base of the scrotum), and his genitalia were Tanner stage 1. Laboratory testing showed a testosterone concentration of 0.36 ng per milliliter (1.25 nmol per liter) (normal value, <0.25), free testosterone 0.0066 ng per milliliter (0.0229 nmol per liter) (reference range, 0.0006 to 0.0057), and DHEA sulfate 278 μg per deciliter (7.6 μmol per liter) (normal value, <75). On questioning, it was determined that the patient was not currently using drugs, herbal supplements, or herbal lotions but was applying a styling gel to his hair and scalp every morning and regularly using a shampoo. The labels of both the gel and the shampoo listed Lavandula angustifolia (lavender) oil and Melaleuca alternifolia (tea tree) oil as ingredients. Reevaluation 9 months after use of these products was discontinued showed that his areolar mounds had decreased in depth to approximately 1 cm with almost no palpable glandular tissue.

Patient 3

A boy who was 7 years 10 months old presented with a 1-month history of gynecomastia that had appeared gradually. His height was between the 75th and 90th percentiles, and his weight was at the 50th percentile. He had bilateral gynecomastia with firm, nontender breast tissue that corresponded to Tanner stage 2. His testes were 3 ml in volume and of normal consistency. His genitalia were Tanner stage 1, and there was no pubic hair present. Laboratory testing showed normal thyroid function, FSH 0.49 IU per liter (reference range, 0.25 to 1.92), luteinizing hormone 0.16 IU per liter (reference range, 0.02 to 1.03), estradiol 5 pg per milliliter (18 pmol per liter) (normal value, <10), estriol less than 0.1 ng per milliliter (0.3 nmol per liter) (normal value, <0.1), estrone less than 13 pg per milliliter (48 pmol per liter) (normal value, <13), total estrogens 61 pg per milliliter (225 pmol per liter) (normal value, <130 in adult men), DHEA sulfate 22 μg per deciliter (0.6 μmol per liter) (reference range, 2.5 to 145), 17-alpha-hydroxyprogesterone 0.13 μg per liter (0.39 nmol per liter) (reference range, 15 to 65), and free beta subunit of human chorionic gonadotropin less than 2 mIU per milliliter (normal value, <5); the serum biochemistry values, including liver-function tests, were normal. His history was positive for the use of lavender-scented soap and intermittent use of lavender-scented commercial skin lotions. The gynecomastia resolved completely a few months after use of scented soap and skin lotions was discontinued (personal communication from the patient's family). His fraternal twin used the same skin lotions, but not the lavender-scented soap, and did not have any gynecomastia.