0913 Guidelines for administration of Growth Hormone (GH) in South Africa

A useful guideline, produced on behalf of the Paediatric and Adolescent Endocrine and Diabetes Society of South Africa (PAEDS-SA), was published recently in the South African Medical Journal. The article is useful because it covers in some detail the conditions currently regarded internationally as being responsive to intervention with recombinant GH. However, included in the list are several conditions which, while demonstrating poor growth, do not actually have GH deficiency, so one is left a little confused by one of the comments in the ‘Proviso’ section that states that the group advocates the use of GH for managing short stature in children with proven GH deficiency, whatever the cause, where there is expected benefit. Be that as it may, the guideline covers the currently-recognised indications, starting with true GH deficiency. This covers abnormalities within the GH and GH-IGF axis (IGF = insulin-like growth factor) i.e. actual GH deficiency, inert GH, GH receptor abnormalities or defects in GH signal transduction and IGF production defects. Testing is complex and results often difficult to interpret, so referral to a sub-specialist in the field is appropriate. Treatment not only improves growth (to final heights of 165-172cm) but also has beneficial physiological effects through actions on adipose tissue, muscle and bone metabolism. A case is also made for treatment of neonatal GH deficiency (GH <20ng/ml associated with hypoglycaemia). Although Turner’s syndrome patients are not GH deficient there is considerable evidence that final height can be increased from the untreated average of 142cm to 149cm with GH. Benefits have also been shown in the Prader-Willi syndrome, not only in terms of growth but also for body composition, functional muscle mass and neurodevelopment. Growth failure may also be corrected to some extent in children with chronic renal insufficiency; however concomitant problems such as acidosis, malnutrition and renal osteodystrophy will impact of the efficacy of GH, and catch-up growth is poor during dialysis and after transplant. Growth failure in children born SGA (small for gestational age) may also respond to GH, but one has to wonder how a greater body mass interacts with evidence that SGA infants are constitutionally metabolically stressed, and improved growth may lead to impaired metabolism in adulthood. Idiopathic short stature is also covered, but the comment is made that further data on final height are awaited to clarify the use of GH in this situation.

Read more:
S Afr Med J 2009; 99: 185-95
Pediatrics 2005; 115: e458-462
Cochrane Database Syst Rev 2007; (3): CD004440