Maurice Asfour

High Prevalence of Diabetes Mellitus and Impaired Glucose Tolerance in the Sultanate of Oman: Results of the 1991 National Survey

A national survey of glucose intolerance and cardiovascular disease risk factors in Oman has demonstrated a high prevalence of diabetes (10%) and impaired glucose tolerance (IGT, 13% in females and 8% in males). Prevalence of diabetes rose with age to a maximum of over 30% in both sexes. Prevalence of total glucose intolerance (diabetes and IGT combined) exceeded 50% in the seventh (females) and eighth (males) decade of life.

Congenital adrenal hyperplasia complicated by central precocious puberty: Linear growth during infancy and treatment with gonadotropin-releasing hormone analog

Some children with congenital adrenal hyperplasia (CAH) develop true precocious puberty with early maturation of the hypothalamic-pituitary-gonadal axis. We have seen six such children who had the diagnosis of CAH with late initiation of corticosteroid treatment and/or poor compliance who developed central precocious puberty (CPP). These patients were treated with standard-dose hydrocortisone and fludrocortisone. Administration of depot leuprorelin (3.75 mg subcutaneously every 28 days) for 2 years or longer was effective in arresting the manifestations of puberty, decelerating the pretreatment growth velocity ([GV] 10.8 +/- 1.5 v3.65 +/- 0.95 cm/yr), increasing the predicted adult height ([PAHT] 147.5 +/- 7.8 v 153.4 +/- 8.3 cm), and decreasing the bone age to statural age ratio (1.26 +/- 0.13 v 1.16 +/- 0.09). Analysis of auxanological data during the first 2 years of life showed that linear growth was significantly accelerated and bone age was advanced in patients who developed CPP compared with 11 age-matched patients. It appears that proper glucocorticoid replacement to achieve adequate control of hyperandrogenemia during early life might prevent development of CPP in these patients. Gonadotropin-releasing hormone agonist (GnRHa) therapy can improve the final adult height, bringing it closer to that expected from the genetic potential.

Testosterone treatment in adolescent boys with constitutional delay of growth and development.

Administration of androgens to adolescent boys with constitutional delay in growth has been highly controversial. One hundred forty-eight adolescent boys with constitutional delay of growth and puberty with a mean age of 14.3 +/- 0.7 years were treated with testosterone enanthate 100 mg intramuscularly each month for 6 months. Growth parameters, sexual maturation, and circulating concentrations of testosterone and insulin-like growth factor-I (IGF-I) were compared with those for 50 age-matched adolescent boys with constitutional delay of growth and puberty with a mean age of 14.1 +/- 0.9 years who did not receive any treatment. The mean height growth velocity, height standard deviation score, weight gain, and IGF-I concentration were significantly greater in the treatment group after 1 year of follow-up evaluation. The advancement in bone age equaled that in chronologic age in the treatment group, with no significant change in the bone age to chronologic age ratio (BA/CA) before versus after therapy. All subjects in the treatment group had clearly entered puberty by the end of 1 year. Testicular size increased significantly in the treatment group and they had significantly higher serum testosterone concentrations 6 months after the end of testosterone therapy as compared with the control group, denoting activation of the hypothalamic-pituitary testicular axis. All subjects in the treatment group were psychologically satisfied with the enhanced growth and increased muscle mass, versus only 40% of those in the control group. In conclusion, our regimen appears to be efficacious and safe for treatment of boys with constitutional delay of growth and puberty and has no deleterious effect on skeletal age.

Empty sellae, impaired testosterone secretion, and defective hypothalamic-pituitary growth and gonadal axes in children with Bardet-Biedl syndrome

We evaluated growth parameters and hypothalamic-pituitary-gonadal and growth functions in five children with Bardet-Biedl syndrome (BBS). Three of the five children had stature below the fifth percentile for age. Their growth hormone (GH) response to provocation was defective, and computed tomographic (CT) scanning revealed empty sellae in all of them. All the children were obese (body mass index [BMI] > 95th percentile for age). Three had hypercholesterolemia. Their basal serum testosterone concentration and testosterone response to 3-day human chorionic gonadotropin (HCG) stimulation were significantly lower than the levels in 12 age-matched obese normal children. Testosterone secretion failed to respond to HCG therapy for 4 weeks. Both basal gonadotropin levels (luteinizing hormone [LH] and follicle-stimulating hormone [FSH]) and gonadotropin responses to LH-releasing hormone (LHRH) stimulation were normal and did not differ among the two study groups. It appears that primary hypogonadism is a cardinal feature of BBS, and it may be accompanied by hypothalamic and pituitary abnormalities.

Defective growth hormone secretion in children with pycnodysostosis and improved linear growth after growth hormone treatment.

Short stature is a characteristic feature of pycnodysostosis. We report defective growth hormone secretion in response to provocation and low insulin-like growth factor-I (IGF-I) concentration in five out of six patients with pycnodysostosis. Physiological replacement with growth hormone increased IGF-I concentration and improved linear growth in these children.

Epidemiology of childhood insulin-dependent diabetes mellitus in the Sultanate of Oman

This study assessed the updated incidence of IDDM in 0 to 14‐year‐old children in the Sultanate of Oman, which is located in the souther‐eastern part of the Arabian peninsula. Incident cases were recorded prospectively from January 1993 to the end of December 1994. Incidence rates were standardized on the basis of the National Population Census. The degree of ascertainment was above 96 % from the primary source. During two full calendar years, 31 new cases of IDDM in children were diagnosed in Oman (10 health regions). The standardized incidence rates were 2.45 and 2.62/100 000 per year during 1993 and 1994, respectively. The sex‐specific rates among males and females were 3.23 and 1.99/100000, respectively, in 1993 and 2.91 and 1.95/100 000, respectively in 1994. The age‐specific incidence rates during the 2 years were higher in the 10–14 age group (3.69 and 4.22/100 000, respectively) vs those in the 5–9 age group (2.32 and 2.79/100000, respectively) and 0.4 age group (1.54 and 0.97/100 000 respectively). The number of new cases/month was markedly higher in the relatively cooler months (September through March) of the year. The incidence rate of IDDM in children under the age of 15 years in Oman was lower than the reported incidence in Kuwait (another gulf country located north‐west to Oman) which might reflect the north–south gradient reported in several previous studies. However this incidence rate was higher than those reported for many countries in Asia.

Growrth hormone secretion and circulating insulin-like growth factor-I (IGF-I) and IGF binding protein-3 concentrations in children with sickle cell disease

Abstract Impaired growth involving both height and weight accompanying sickle cell disease (SCD) poses diagnostic and therapeutic problems. We undertook this study to test the hypothesis that this impaired growth is associated with abnormalities of the growth hormone (GH)/insulin-like growth factor-I (IGF-I)/IGF binding protein-3 (IGFBP-3)axis in 21 children with SCD and that SCD is associated with GH resistance. Nine of 21 children with SCD had a defective GH response to both clonidine and glucagon provosation (peak, d -xylose. A single injection of GH produced a smaller increase in circulating IGF-I in children with SCD with or without defective GH secretion versus 10 age-matched children with idiopathic short stature (ISS) and 11 children with isolated GH deficiency (GHD), suggesting partial GH resistance in the SCD group. The presence of defective GH secretion, decreased IGF-I synthesis, and partial resistance to GH in short children with SCD suggests that treatment with IGF-I may be superior to GH therapy for improving growth.

Growth and endocrine function after near total pancreatectomy for hyperinsulinaemic hypoglycaemia.

Seven children, with a mean (SD) age of 4.6 (2.1) years, who as infants (21 (7.5) days) underwent near total (95-98%) pancreatectomy for persistent hyperinsulinaemic hypoglycaemia of infancy (PHHI) were studied. At birth all the infants were macrosomic. Four infants had been born after a difficult labour, of whom three had moderate birth asphyxia and respiratory distress. All had normal thyroid function. After surgery transient hyperglycaemia was manifest in six of the children and required insulin treatment for 5.8 (3.8) weeks, and transient hypoglycaemia was encountered in one child and responded well to increased carbohydrate intake and diazoxide for three weeks. Six of the children rapidly crossed down their length and weight centiles during the first year after surgery. At the end of the first year these children were at or below the 5th centile of height and weight for their age and gender. After a period of 4.6 (2.1) years, their mean (SD) height score was -2.57 (0.5), growth velocity 3.9 (0.75) cm/year, and growth velocity SD score -2.1 (0.55)l these were significantly low and denoted significant growth retardation. The growth hormone peak responses to provocation with clonidine were normal (13.5 (2.8) micrograms/l). However, the circulating insulin-like growth factor-I (IGF-I) concentrations were significantly decreased (79 (34) ng/ml). Three of the children developed diabetes at two and a half, five, and seven years after surgery, two others had impaired oral glucose tolerance and six out of the seven children had an impaired C peptide response to glucagon. Defective insulin secretion in these children might directly inhibit IGF-I synthesis in the liver. The body mass index of the pancreatectomised children was 14.9 (0.5) and was normal for age and gender; they had a normal 72 hour faecal fat content and normal serum albumin concentration. These data indicated grossly adequate exocrine pancreatic function. It appears that children requiring near total pancreatectomy for PHHI have normal developmental milestones but defective linear growth with impaired insulin secretion and low IGF-I production despite normal growth hormone response to provocation.

Growth hormone deficiency and empty sella in DIDMOAD syndrome: an endocrine study.

Two girls with DIDMOAD syndrome are presented. One also had severe megaloblastic-sideroblastic anaemia and the other several neurological manifestations. Both were short with defective growth hormone secretion. Computed tomography revealed empty sella in both girls; one had widespread atrophic cortical and cerebellar changes. High doses of thiamine improved the anaemia in the first case, increased C peptide secretion in both, but had no effect on the neurological abnormalities.

Permanent neonatal diabetes mellitus: Epidemiology, mode of presentation, pathogenesis and growth

Permanent neonatal diabetes mellitus (PNIDDM) is a rare form of IDDM with unclear etiology and pathogenesis. We determined the incidence and prevalence rates and studied the clinical and biochemical features of PNIDDM in the Sultanate of Oman. The mean incidence rate during the study period from January 1989 to December 1994 was 1.788±0.82 per 100,000 live births per year. At the end of December 1994 the prevalence rate was 2.4 per 100,000 children below the age of 5 years. They constituted 41.6% of all cases of IDDM in this age group. Diarrhoea, fever, lethargy, poor feeding and failure to thrive were the most common presenting symptoms. Dehydration and tachypnoea were the most common signs. All patients who developed IDDM during the neonatal period had intrauterine growth retardation and 4.5 presented with diabetic ketoacidosis (plasma glucose 37±9 mmol/L, pH 7.12±0.1). Hypertriglyceridemia was a constant feature (19.4±4.8 mmol/L). They were products of consanguineous marriage with significantly high prevalence of IDDM and NIDDM in their family members. None of the infants had clinical or immunological evidence of congenital viral infection. Three of the five children had HLA-DR2, the diabetes resistance alleles. C-peptide secretion was absent during and after metabolic control of hyperglycemia in all the studied infants and none had circulating islet cell antibody at presentation or during the first year after diagnosis. Despite marked growth retardation at birth, there was a significant improvement of growth after initiating insulin therapy. Four of the 5 patients had normal developmental milestones, one had mild developmental delay following a severe and prolonged attack of hypoglycemia. None of the patients had exocrine pancreatic deficiency. In summary, the very high rate of parental consanguinity, occurrence in both sexes and in two siblings in the same family, absence of islet cell antibodies and the presence of HLA-DR2 loci in 3/5 of patients suggest that PNIDDM is a different disease process to standard IDDM in childhood and an autosomal recessive mode of transmission.