Adolescent Growth and Development

Educational Objectives

The goal of this lecture is to improve the assessment of pubertal development. After hearing and assimilating this lecture, the clinician will be better able to:

1. Assess pubertal development using the Tanner stages.
2. Recognize the signs and symptoms of precocious puberty and delayed puberty.

Summary

Background: pubertal development involves transition from immaturity to sexual maturity with fertility and development of secondary sexual characteristics; decreasing sensitivity of hypothalamic–pituitary–gonadal (HPG) axis and increasing pulsatile release of gonadotropin-releasing hormone (GnRH), luteinizing hormone (LH), and follicle-stimulating hormone (FSH); sex differences — formation of breast buds (thelarche) first sign of pubertal development in girls; significant variations in timing, onset, and tempo of puberty, and magnitude of changes; order of progression through puberty predictable; testicular growth first sign of pubertal development in boys

Normal puberty: mean age of onset 11 yr for girls and 11.5 yr for boys; progression from Tanner stage II to V requires 2 to 4 yr; girls — thelarche, followed by adrenarche, peak height velocity (≈12 yr and Tanner stage III-IV), and menarche (≈2 yr after thelarche); boys — testicular enlargement (≈11.5 yr), followed by adrenarche, penile enlargement, peak height velocity (≈14 yr and Tanner stage IV)

Normal variants in puberty: premature thelarche — early breast development without other signs of puberty; occurs <2 yr or >6 yr of age; premature adrenarche — occurs between 6 and 8 yr of age; no height acceleration or advancement in bone age; re-evaluate every 4 to 6 mo

Tanner stages: girls — stage II elevation of breast bud and sparse, long pubic hairs; stage III enlargement of breast bud and coarser pubic hair; stage IV areola and papilla form mound on top of remainder of breast and adult pubic hair distributed throughout small area; stage V mature adult with flat areola and extension of pubic hair onto inner thigh; boys — stage II testicular development, scrotal thinning, and sparse pubic hair; stage III enlargement of penis in length and width, and further testicular and scrotal growth; stage IV further enlargement of penis and testes, and adult pubic hair in distributed throughout small area; stage V mature adult (testes ≈20 cc)

Gynecomastia: affects 75% of boys during puberty (Tanner stages II-III); typically resolves within 2 yr; occurs from estrogen/androgen imbalance or increased tissue sensitivity; screen for Klinefelter syndrome, exposure to estrogens or anti-psychotic medications, and breast tumors; treatment — reassurance; surgery reserved for refractory cases, especially those associated with issues related to body image

Precocious puberty: onset of puberty <8 yr of age for girls and <9 yr of age for boys; central precocious puberty (CPP) — reactivation of HPG axis; more common in girls (mostly idiopathic); in boys, >60% of cases associated with neurologic causes; peripheral precocious puberty (PPP) — caused by late-onset congenital adrenal hyperplasia (CAH), ovarian/testicular tumors, McCune–Albright syndrome, exogenous hormones, and hypothyroidism

Evaluation: bone age — advanced with precocious puberty (not advanced with premature thelarche or adrenarche); laboratory tests — gonadotropins (not helpful); GnRH stimulation test (brisk rise in LH and FSH with CPP; no rise in LH or FSH in prepubertal children or PPP); estradiol and testosterone levels; thyrotropin and free T4; dehydroepiandrosterone sulfate (DHEA-S) and 17-hydroxyprogesterone (to rule out hypothyroidism, late-onset CAH, and adrenal tumors); pelvic ultrasonography — can be used to identify large ovarian cysts and neoplasms; assess development of uterus and ovaries; high-resolution head magnetic resonance imaging — boys with CPP or girls <5 yr of age; imaging — adrenals and gonads

Delayed puberty: lack of secondary sexual characteristics by age of 13 yr in girls or 14 yr in boys; patients generally smaller than peers; more common in boys; lack of progression through stages of puberty by 5 yr after onset of puberty; can cause psychological and social issues; etiologies — constitutional growth delay most common; hypopituitarism; Kallmann syndrome; chronic illness; malnutrition; hypothyroidism; hyperprolactinemia; Turner syndrome; Klinefelter syndrome

Evaluation: bone age — onset of puberty correlates better with bone age than chronologic age; laboratory tests — FSH and LH (may be elevated); thyroid studies; prolactin; imaging — check central nervous system for intracranial lesions; karyotype — rule out Turner and Klinefelter syndromes

Constitutional growth delay: short stature or low-normal growth velocity; delayed bone age; positive family history

Turner syndrome: affects 1 in 5000 live-born girls; typically 45 XO or 46 XX with mosaicism; skeletal growth disturbance (eg, short stature) common; cardiovascular and renal issues; gonadal failure

Readings

Carel JC et al: Precocious puberty and statural growth. Hum Reprod Update, 2004 Mar-Apr;10(2):135-47; Latronico AC et al: Causes, diagnosis, and treatment of central precocious puberty. Lancet Diabetes Endocrinol, 2016 Mar;4(3):265-74; Rosenfield RL et al: Thelarche, pubarche, and menarche attainment in children with normal and elevated body mass index. Pediatrics, 2009 Jan;123(1):84-8; Villanueva C, Argente J: Pathology or normal variant: what constitutes a delay in puberty? Horm Res Paediatr, 2014;82(4):213-21; Wei C, Crowne EC: Recent advances in the understanding and management of delayed puberty. Arch Dis Child, 2016 May;101(5):481-8.

Disclosures

For this program, members of the faculty and planning committee reported nothing to disclose.

Acknowledgements

Dr. Issac was recorded at The 22nd Annual Pediatric Board Review, held August 29-September 2, 2016, in Cleveland, OH, and sponsored by The Cleveland Clinic Foundation. For information about upcoming CME activities from The Cleveland Clinic Foundation, please visit www.ccfcme.org/GoPedReview. The Audio Digest Foundation thanks Dr. Issac and The Cleveland Clinic Foundation for their cooperation in the production of this program.

CME/CE INFO

Accreditation:

The Audio- Digest Foundation is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians.

The Audio- Digest Foundation designates this enduring material for a maximum of 0 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

Audio Digest Foundation is accredited as a provider of continuing nursing education by the American Nurses Credentialing Center's (ANCC's) Commission on Accreditation. Audio Digest Foundation designates this activity for 0 CE contact hours.

Lecture ID:

PD631602

Expiration:

This CME course qualifies for AMA PRA Category 1 Credits™ for 3 years from the date of publication.

Instructions:

To earn CME/CE credit for this course, you must complete all the following components in the order recommended: (1) Review introductory course content, including Educational Objectives and Faculty/Planner Disclosures; (2) Listen to the audio program and review accompanying learning materials; (3) Complete posttest (only after completing Step 2) and earn a passing score of at least 80%. Taking the course Pretest and completing the Evaluation Survey are strongly recommended (but not mandatory) components of completing this CME/CE course.

Estimated time to complete this CME/CE course:

Approximately 2x the length of the recorded lecture to account for time spent studying accompanying learning materials and completing tests.

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