Acromegaly in an infant.
Serial hormonal studies were carried out in a girl with a growth hormone-secreting pituitary adenoma and hyperprolactinemia diagnosed at 21 months of age, the youngest verified case of acromegaly. The child had progressive macrocephaly, noted at 6 months of age, which preceded the rapid acceleration of linear growth by nearly 1 year. At 21 months of age, the girl's head circumference measured 55 cm (+5.5 SD) and her height was 97.6 cm (+4.4 SD). Preoperative serum growth hormone level was 135 ng/mL, somatomedin C was 1,540 ng/mL (normal for bone age 18 to 97 ng/mL), and prolactin was 370 ng/mL (normal less than 20 ng/mL). Following total resection of a large adenoma, immunohistochemical staining of the tumor showed growth hormone but not prolactin. With longitudinal monitoring of the child for 2 years postoperatively, persistently low growth hormone levels were demonstrated and normal growth velocity (6 cm/yr). Peak serum growth hormone levels ranged from 2.8 to 4.1 ng/mL after stimulation tests with insulin, arginine, and L-dopa. Maximum sleep-entrained growth hormone level was 3.4 ng/mL. At the same time, serum somatomedin C levels measured serially were normal (29 to 111 ng/mL), whereas simultaneous prolactin levels were moderately increased (30 to 147 ng/mL). The data support the hypothesis that hyperprolactinemia may have contributed to stimulating somatomedin C and sustaining the normal growth rate in this child.
Blumberg
D L
DL
Department of Pediatrics, New York University Medical Center, NY 10016.
Sklar
C A
CA
David
R
R
Rothenberg
S
S
Bell
J
J
D000172:Acromegaly / Q000097:blood / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D000236:Adenoma / Q000150:complications / Q000175:diagnosis / Q000378:metabolism / Q000601:surgery; D005260:Female; D005500:Follow-Up Studies; D006128:Growth; D013006:Growth Hormone / Q000097:blood / Q000378:metabolism; D006801:Humans; D006966:Hyperprolactinemia / Q000150:complications / Q000175:diagnosis / Q000601:surgery; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D007223:Infant; D007334:Insulin-Like Growth Factor I / Q000097:blood; D010911:Pituitary Neoplasms / Q000150:complications / Q000175:diagnosis / Q000378:metabolism / Q000601:surgery; D011388:Prolactin / Q000097:blood
D007334:Insulin-Like Growth Factor I; D011388:Prolactin; D013006:Growth Hormone