Constitutional delay and familial short stature — branching viva

Opening question

A fourteen-year-old boy has no signs of puberty, a bone age of eleven years, and a father who shaved late. His height is appropriate for his bone age. What is the most likely diagnosis, and what single comparison at the bedside confirms it? [3] [4]

Branch 1 — distinguishing the variants and the mimic

How do you distinguish constitutional delay from familial short stature, and what is the discriminator? Then, how would the presentation differ if this were growth hormone deficiency rather than a normal variant? [1] [2]

Branch 2 — the short girl and Turner syndrome

Now consider a twelve-year-old girl with short stature, no breast development, and a delayed bone age. Why must Turner syndrome stay on the differential even without classic stigmata, and what investigation secures the distinction before the short stature is labelled constitutional? [1]

Branch 3 — the distressed adolescent and the offer of therapy

The boy is distressed by his prepubertal appearance among his peers. What is the role of a short course of testosterone, what is a representative dose and duration, and what are its goals and its limits? Why is growth hormone not indicated? [3] [4]

Closing — the principle

In one sentence, what is the single most testable principle that governs the management of the normal variants of short stature? [1] [2]