C. Zecchino

Transient neonatal diabetes mellitus is associated with a recurrent (R201H) KCNJ11 (KIR6.2) mutation.

To the Editor: Neonatal diabetes mellitus (NDM) is a rare, monogenic form of diabetes currently defined as insulinrequiring hyperglycaemia within the first 3 months of life [1]. Neonatal diabetes can be either permanent (PNDM), requiring life-long insulin treatment, or transient (TNDM), the latter usually subsiding within 12 months of onset. In some patients with TNDM a relapse of diabetes can occur during adolescence. Recently, activating mutations of KCNJ11 (previously known as KIR6.2), encoded by the KCNJ11 gene, have been found to result in the permanent form of this condition [2]. In addition, KCNJ11 mutations with a milder effect can also give rise to remitting, relapsing, or transient neonatal diabetes [3]. In this study, the genetic basis of a case of neonatal diabetes with an atypical clinical course was investigated. The proband (referred to as nd-BA/2) is now 20 years old, and is the only child born to healthy, unrelated parents. She was delivered at term with a weight of 2,300 g (10th centile). Her random plasma glucose was found to be elevated during the 2nd day of life, with values ranging from 10.0 to 16.6 mmol/l without ketonuria. During the first 5 weeks of life the child was in good general health and showed a regular increase of body weight despite high plasma glucose levels. Fasting C-peptide was detectable (149 pmol/l, reference values: 178–680) and tests for anti-beta-cell autoantibodies were negative. Insulin therapy was not begun until the age of 37 days, when due to severe hyperglycaemia (32 mmol/l), ketonuria and a failure to thrive, a daily dose of 1.1 U kg day was administered. After stabilisation, insulin treatment was progressively reduced and stopped at the age of 29 months because of good metabolic control and episodes of hypoglycaemia. Two OGTTs performed 5 and 17 months after insulin withdrawal showed that the patient had progressed from IGT to normal glucose tolerance (Table 1). HbA1c, determined once a year during the following 4 years, was always below 7% (4.1–6.3%). An OGTT performed at the age of 7 years and 7 months showed a recurrence of diabetes (Table 1), and 6 months later insulin therapy was re-established (0.8 U kg day) because of persistently high HbA1c values (11.5%). At around the same age anti-gliadin autoantibodies were detected in the absence of clinical symptoms. Coeliac disease was confirmed by biopsy and the child was put on a glutenfree diet. In November 2004, informed consent for genetic analysis was obtained from the proband. The intronless KCNJ11 gene was amplified in three overlapping fragments (B, C and D), with a primer pair previously described for B and C fragments [4] and modified for the D fragment (D forward: 5′ ccg ctg atc atc tac cat gtc 3′; D reverse: 5′ tac cac atg gtc cgt gtg tac 3′). We identified a heterozygous R201H mutation (c.602 G→A) that arose de novo in the patient. C. Colombo . F. Barbetti Laboratory of Molecular Endocrinology and Metabolism, Bambino Gesù Children’s Hospital, Scientific Institute (IRCCS), Rome, Italy

Growth deficiency in polytransfused β-thalassaemia patients is not growth hormone dependent

Growth deficiency is commonly seen in polytransfused β‐thalassaemia patients, especially in adolescence. It is not completely dependent on the lack of their pubertal growth spurt. GH impairment at different levels (hypothalamic or pituitary) and/or a reduced IGF‐1 synthesis have been suggested the main causes of stunted growth in these patients. We evaluated the relationship between GH reserve and growth in short β‐thalassaemia patients.

Longitudinal Assessment of Levo-Thyroxine Therapy for Congenital Hypothyroidism: Relationship with Aetiology, Bone Maturation and Biochemical Features

Aims: To evaluate therapy and dose adjustments in patients with congenital hypothyroidism (CH), longitudinally followed up until 16 years old, according to aetiology, Beclard’s nuclei presence, and thyroxine (T4) level at diagnosis. Methods:L-T4/kg/day and dose change ratio (CR) were assessed in 74 CH patients. Results: The dose was statistically larger in athyreosis than in dyshormonogenesis (1–10 and beyond 14 years) and in ectopy (2, 15, 16 years). The ectopic children required statistically larger L-T4/kg than the dyshormonogenetic ones (3–7 years). The L-T4/kg/day was increased, not statistically, in patients or with T4 <30 nmol/l or without Beclard’s nuclei at diagnosis. The CR progressively dropped after the 6th month at each attendance, without any difference in terms of aetiology, T4 level at diagnosis, or Beclard’s nuclei. The total CR was greater (significantly) in patients without Beclard’s nuclei, and (not significantly) in those with T4 <30 nmol/l at diagnosis or with agenesia. Conclusion: The L-T4 dose in CH is highly affected by the aetiology. The CR is higher in patients with delayed bone maturation at diagnosis. We suggest that these latter patients need blood tests more frequently to obtain a proper titration of the therapy.

Factors predicting final height in early treated congenital hypothyroid patients

Objective  To evaluate pubertal development and final height (FH) in early treated patients with congenital hypothyroidism (CH) and to identify the main factors predicting FH.

Growth hormone release during insulin tolerance, Clonidine, arginine and growth hormone releasing hormone tests in short normal children and adolescents

This study was retrospectively performed in 574 short normal children and adolescents [328 underwent insulin tolerance test (ITT), 34 Clonidine test (CLON), 64 arginine test (ARG), 19 GHRH test, 52 ITT+CLON, 30 GHRH+CLON, and 47 ITT+CLON+GHRH) in order to evaluate the effect of pubertal stage on G H response to different tests and to identify the most likely mechanism of action of different stimuli. GH peak was higher during GHRH than in all other tests. Sex or start of pubertal development did not cause any GH peak difference. Low-responder (GH peak <10ng/ml) percentages were similar (ITT = 13.5%, CLON = 13.4%, ARG = 13.2%, GHRH = 10.6%) also when the subjects were divided according to sex and pubertal development. ITT+CLON showed discordant results in 42/99 subjects (30/42 = 71.4% were low-responders to ITT and 12/42 = 28.6% to CLON). GH peak appeared earlier during GHRH (85% <45 min) and later during CLON (78%: 60–120 min) than during all other tests; GH peak during ITT showed a wide variability of time. Negative correlations were found between GH peak during GHRH and chronological age, height and bone age and during CLON and chronological age. In conclusion our data show that these tests have similar GH secretagogue reliability.

Final height in short polytransfused thalassemia major patients treated with recombinant growth hormone

We measured the final height (FH) of 25 short polytransfused thalassemia major (Th) patients (18 males) with a reduced GH reserve treated for 3.3±1.2 yr with recombinant GH (rhGH), 0.2 mg/kg/week sc. At baseline, all patients were clinically prepubertal; their chronological (CA) and bone ages (BA) were 13.6±2.0 and 11.4±1.6 yr, respectively. In 9 out of 18 males and 5 out of 7 females, the onset of puberty occurred spontaneously during the treatment. At the end of the rhGH administration, the height of the enrolled children was not significantly increased when calculated for CA (HxCA), while it was significantly decreased (p=0.004) when calculated for BA (HxBA); the BA increase (3.29±1.65 yr) was significantly higher (p<0.001 ) than the height age increase (2.16±0.98 yr). The FHxCA showed a significant increase (p=0.001) compared to both baseline and the end of therapy, while the FHxBA was significantly decreased (p<0.001) compared with the corresponding value at baseline. At the end of therapy, both HxCA and HxBA resulted positively related to the BA at baseline (r=0.50 and 0.42, p=0.012 and 0.034, respectively). FH was positively correlated with CA (r=0.63, p=0.001), BA (r=0.68, p<0.001) and HxBA (r=0.59, p=0.002) evaluated at baseline, and with both HxCA and HxBA (r=0.82 and 0.74, respectively, p<0.001), evaluated at the end of treatment. A negative correlation was found between FH and the length of treatment (r=−0.56, p=0.004). Our data seem to exclude that prolonged rhGH therapy could improve FH in Th patients; on the contrary, a negative effect may be hypothesized.

Effects of moderate-severe exercise on blood glucose in Type 1 diabetic adolescents treated with insulin pump or glargine insulin.

Background: Few papers focus on exercise-related blood glucose (BG) in patients on continuous sc insulin infusion (CSII) or multiple daily injections (MDI) with glargine. Aim: The main objective was to evaluate the degree of glycemic control in Type 1 diabetes mellitus adolescents on CSII doing physical activity with pump switched on or off. These findings were also compared with a small group of patients on MDI with glargine. Subjects and methods: Eight patients on CSII (basal rate continued or turned off in alternating sessions) and 5 on MDI joined 4 sessions of moderate-severe exercise. Results: Post-exercise BG significantly increased with the pump off and was unchanged/decreased with the pump on and MDI groups vs baseline. The hypoglycemia rate was not different among the 3 groups at any time. Pump on: hypoglycemias more frequent both at bed-time (p=0.031) and at awakening (p<0.001) than before dinner and at awakening than at bed-time (p=0.044). Pump off: hypoglycemias more frequent both at bed-time (p=0.010) and at awakening (p=0.031) than before dinner. MDI: no differences. Conclusions: Glargine is safe and reducing the prelunch insulin is unnecessary. Subjects on insulin pump should not stop the basal rate. If they stop the pump, some actions are advisable: pre-exercise insulin bolus, pre-sleeping snack rich in carbohydrates, slight reduction of the overnight basal rate. On the other hand, if the basal rate is unmodified, the ingestion of sugary drinks during the exercise, the reduction of the overnight basal rate, a reduction of the pre-dinner insulin bolus and/or a pre-sleeping snack should be considered.

Recombinant growth hormone treatment in short patients with thalassemia major: results after 24 and 36 months.

Abstract Treatment with recombinant growth hormone (rhGH), 0.6 IU/kg/week s.c., previously successfully conducted for one year, was continued in 15 (Group A) and 8 (Group B) short thalassemia major patients with reduced GH reserve, for two and three years, respectively. In Group A, height for chronological: age (Ht SDSca) increased significantly (p = 0.021) from the start of treatment, but the positive effect was only apparent because of the concomitant slight worsening of height for bone age (Ht SDSba). Median AHt SDScA/AHt SDSba was <1.0 with respect to both the start (0.87) and the end of the first year of rhGH therapy (0.89). IGF-I levels increased significantly (p = 0.043) compared with values both at the start and at the end of the first year of rhGH therapy. In Group B neither Ht SDSca : nor Ht SDSba differed statistically from starting values, the former having a positive trend and the latter a negative one. Median AHt SDScA/AHt SDSba was 0.92 with respect to the start, and 0.94 with respect to the end of the second year. IGF-I levels increased significantly (p = 0.043) with respect to starting values. Our data show that the encouraging results described from the first year of rhGH treatment did not persist during the second and third years, and we conclude that this is because increase in bone age with continued treatment is equal to, or slightly greater than the height age increase. We propose that patients with thalassemia major with short stature should receive rhGH treatment for only one year, and that more prolonged treatment should be reserved for selected adolescents who have psychological problems due to shortness; for these patients growth acceleration could represent the main goal, even if this leads to a substantially unchanged or slightly decreased final height.

Subcutaneous Growth Hormone Administration in Growth-Hormone-Deficient Children

The aim of this study, performed in 10 children, was to verify if a treatment schedule, better reproducing the growth hormone (GH) physiological pattern, could achieve a greater growth response than daily s.c. administration in previously successfully treated children with an isolated idiopathic GH deficiency. A 1-month washout period was observed between the previous regimen and this study. GH (0.6 U/kg/week, the same as given previously) was administered weekly in 6 equal doses. Three children received the daily dose by a single s.c. administration (at 20.00 h) and the other 7 through a 27-gauge infusion needle inserted s.c., using a mini infusion pump permitting a constant delivery of 50% of the daily dose (20.00-08.00 h) and the administration of the other 50% through 3 equal pulses (at 20.00, 24.00, and 04.00 h). After 6 months each child changed regimen undergoing the other one with a 1-month washout interval. During the 12 months of therapy, the mean height increased from -3.2 (SE 0.45) to -2.8 (SE 0.37) SDS. When evaluating the circulating insulin-like growth factor-I pattern as well as the growth velocity and the ratio bone age increase/height age increase, no differences were noted between the two treatment regimens.

A Multicenter Retrospective Survey regarding Diabetic Ketoacidosis Management in Italian Children with Type 1 Diabetes

We conducted a retrospective survey in pediatric centers belonging to the Italian Society for Pediatric Diabetology and Endocrinology. The following data were collected for all new-onset diabetes patients aged 0–18 years: DKA (pH < 7.30), severe DKA (pH < 7.1), DKA in preschool children, DKA treatment according to ISPAD protocol, type of rehydrating solution used, bicarbonates use, and amount of insulin infused. Records (n = 2453) of children with newly diagnosed diabetes were collected from 68/77 centers (87%), 39 of which are tertiary referral centers, the majority of whom (n = 1536, 89.4%) were diagnosed in the tertiary referral centers. DKA was observed in 38.5% and severe DKA in 10.3%. Considering preschool children, DKA was observed in 72%, and severe DKA in 16.7%. Cerebral edema following DKA treatment was observed in 5 (0.5%). DKA treatment according to ISPAD guidelines was adopted in 68% of the centers. In the first 2 hours, rehydration was started with normal saline in all centers, but with different amount. Bicarbonate was quite never been used. Insulin was infused starting from third hour at the rate of 0.05–0.1 U/kg/h in 72% of centers. Despite prevention campaign, DKA is still observed in Italian children at onset, with significant variability in DKA treatment, underlying the need to share guidelines among centers.