The growth hormone-insulin-like growth factor axis in glycogen storage disease type 1: evidence of different growth patterns and insulin-like growth factor levels in patients with glycogen storage disease type 1a and 1b.
OBJECTIVE
To investigate the growth hormone (GH)-insulin-like growth factor (IGF) system in patients with glycogen storage disease type 1 (GSD1).


METHODS
This was a prospective, case-control study. Ten patients with GSD1a and 7 patients with GSD1b who were given dietary treatment and 34 sex-, age-, body mass index-, and pubertal stage-matched control subjects entered the study. Auxological parameters were correlated with circulating GH, either at basal or after growth hormone releasing hormone plus arginine test, insulin-like growth factors (IGF-I and IGF-II), and anti-pituitary antibodies (APA).


RESULTS
Short stature was detected in 10.0% of patients with GSD1a, 42.9% of patients with GSD1b (P = .02), and none of the control subjects. Serum IGF-I levels were lower in patients with GSD1b (P = .0001). An impaired GH secretion was found in 40% of patients with GSD1a (P = .008), 57.1% of patients with GSD1b (P = .006), and none of the control subjects. Short stature was demonstrated in 3 of 4 patients with GSD1b and GH deficiency. The prevalence of APA was significantly higher in patients with GSD1b than in patients with GSD1a (P = .02) and control subjects (P = .03). The GH response to the provocative test inversely correlated with the presence of APA (P = .003). Compared with levels in control subjects, serum IGF-II and insulin levels were higher in both groups of patients, in whom IGF-II levels directly correlated with height SD scores (P = .003).


CONCLUSIONS
Patients with GSD1a have an impaired GH secretion associated with reference range serum IGF-I levels and normal stature, whereas in patients with GSD1b, the impaired GH secretion, probably because of the presence of APA, was associated with reduced IGF-I levels and increased prevalence of short stature. The increased IGF-II levels, probably caused by increased insulin levels, in patients with GSD1 are presumably responsible for the improved growth pattern observed in patients receiving strict dietary treatment.
Melis
Daniela
D
Department of Pediatrics, Federico II University, Naples, Italy.
Pivonello
Rosario
R
Parenti
Giancarlo
G
Della Casa
Roberto
R
Salerno
Mariacarolina
M
Balivo
Francesca
F
Piccolo
Pasquale
P
Di Somma
Carolina
C
Colao
Annamaria
A
Andria
Generoso
G
D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D001827:Body Height / Q000502:physiology*; D015992:Body Mass Index; D016022:Case-Control Studies; D002648:Child; D003430:Cross-Sectional Studies; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005500:Follow-Up Studies; D005953:Glycogen Storage Disease Type I / Q000097:blood* / Q000150:complications / Q000503:physiopathology; D006130:Growth Disorders / Q000453:epidemiology / Q000209:etiology* / Q000503:physiopathology; D013006:Growth Hormone / Q000097:blood*; D006801:Humans; D015592:Immunoradiometric Assay; D007558:Italy / Q000453:epidemiology; D008297:Male; D015995:Prevalence; D011379:Prognosis; D011446:Prospective Studies; D012307:Risk Factors; D013002:Somatomedins / Q000378:metabolism*; D013997:Time Factors; D055815:Young Adult
D015415:Biomarkers; D013002:Somatomedins; D013006:Growth Hormone