Table 1.
Current indications for use of GH therapy in PWS
| Age | Testing | GH stimulation tests | Peak GH cutoff for diagnosing GHD | Dosage |
|---|---|---|---|---|
| Childhood | No9,10 | 0.5 mg/m2/day, with subsequent adjustment toward 1.0 mg/m2/day9 | ||
| Transition phase | Yes | GHRH + arginine | <19 µg/L89,* | 0.1–0.2 mg/day |
| ITT | <5 µg/L34 | |||
| Adulthood | Yes | GHRH + arginine | BMI <25: <11.5 µg/L90 | 0.1–0.2 mg/day9 |
| BMI 25–30: <8 µg/L90 | ||||
| BMI >30: <4.2 µg/L90 | ||||
| ITT | <3 µg/L34 |
Notes:
*
Italian criteria for determining GHD in PWS during transition phase: (i) three or more pituitary hormone deficiencies, and (ii) a peak GH level <4.1 µg/L after GHRH plus arginine test after a GH wash-out period prior to retesting of at least 1 month.
Abbreviations: GH, growth hormone; PWS, Prader–Willi syndrome; GHD, GH deficiency; GHRH, GH-releasing hormone; ITT, insulin tolerance test; BMI, body mass index.