Kunio Wataki

Association of HLA-DR, DQ genotype with different beta-cell functions at IDDM diagnosis in Japanese children.

Japanese IDDM patients have been demonstrated to have unique and different HLA associations from white patients. To elucidate the effect of HLA-associated genetic factors on the clinical heterogeneity of IDDM in Japanese people, HLA-DRB1, DQA1, and DQB1 genotypes in 88 childhood-onset Japanese IDDM patients were examined by polymerase chain reaction-sequence-specific oligonucleotide (PCR-SSO) or sequence-specific primers (SSP). Of the 88 IDDM patients, 26 (29.5%) had DRB1*0405-DQA1*0302-DQB1*0401/X (DR4-DQ4/X), 38 (43.2%) had DRB1*0901-DQA1*0302-DQB1*0303/X (DR9-DQ9/X), and 9 (10.2%) were DR4/9-DQ4/9 heterozygous in the present study (X does not contain protective alleles). Clinical heterogeneity such as age distribution at onset, prevalence and serum level of anti-GAD antibodies (GADAb), and residual pancreatic β-cell function after diagnosis were compared between patients with HLA-DR4-DQ4 and DR9-DQ9. The frequency of DR9-DQ9 genotype was significantly higher in the younger (0–10 years) than in the older (11–16 years) age-group of onset, but the frequency of DR4-DQ4 was higher in the older (11–16 years) age-group. Although no association of DR-DQ genotypes with the prevalence and serum level of GADAb was found among newly diagnosed patients, long-standing DR9-DQ9 patients had significantly higher levels of GADAb than those with DR4-DQ4. While no difference in time course of serum C-peptide (CPR) levels was detected between GADAb+ and GADAb− patients, a remarkable difference was demonstrated between DR9-DQ9 and DR4-DQ4 patients. The residual pancreatic β-cell function was retained more in patients with DR4-DQ4 than in those with DR9-DQ9 at diagnosis through 12–18 months after diagnosis. These results suggest that the DR9-DQ9 genotype may induce stronger autoimmune destructive response (T-helper 1 function) against target β-cells than the DR4-DQ4 genotype does. Our findings may warrant further studies on the association of diabetogenic autoimmune response with HLA class II molecules and contribute to a clarification of interracial differences in HLA-encoded susceptibility to IDDM.

Cytotoxic T lymphocyte antigen 4 gene polymorphism confers susceptibility to Type 1 diabetes in Japanese children: analysis of association with HLA genotypes and autoantibodies

OBJECTIVE Although the polymorphisms of the cytotoxic T lymphocyte antigen 4 (CTLA4) gene have been shown to be associated with Type 1 diabetes in Caucasians, some conflicting results have been reported among subjects of different ethnic backgrounds. We examined a CTLA4 polymorphism and its relationship to human leucocyte antigen (HLA) genotypes and autoantibodies for glutamic acid decarboxylase 65 (GAD65) and IA‐2 in Japanese children with Type 1 diabetes.

Attainment of normal height in severe juvenile hypothyroidism.

Prolonged juvenile hypothyroidism results in a permanent loss in height that is related to the duration of thyroxine deficiency before adequate thyroxine replacement treatment. A 13 year old girl with severe juvenile hypothyroidism was studied prospectively. She had an undetectable serum thyroxine concentration, a height SD score of -6.6 SD, and a bone age of 5.8 years. The enlarged pituitary gland involuted with thyroxine treatment to produce an empty sella. In addition to thyroxine the girl was treated with a gonadotrophin releasing hormone agonist to avoid the progression of puberty for 18 months and with growth hormone to achieve normal adult height.

Comparison of methimazole and propylthiouracil in the management of children and adolescents with Graves’ disease: efficacy and adverse reactions during initial treatment and long-term outcome

Abstract Objective: The aim of this study was to compare the efficacy and adverse reactions during initial treatment and long-term outcome between children and adolescents with Graves’ disease (GD) treated with propylthiouracil (PTU) and those treated with methimazole (MMI). Design, setting and participants: Retrospective and collaborative study. Children and adolescents with GD were divided into group M (MMI: n=64) and group P (PTU: n=69) and into four subgroups by initial dose: group M1 (<0.75 mg/kg of MMI, n=34), group M2 (≥0.75 mg/kg, n=30), group P1 (<7.5 mg/kg of PTU, n=24) and group P2 (≥7.5 mg/kg, n=45). Main outcome measures: The duration for normalization of serum T4 on initial treatment, the incidence of adverse effects for one year and outcomes at 10 years after were compared. Results: Mean durations for normalization of T4 (±SD) were 1.7±1.0 months in group M and 2.3±2.4 in group P [not significant (NS)], while the mean duration in group P1 (3.1±3.3) was significantly longer than those in the other subgroups (M1: 1.9±1.2; M2: 1.4±0.7; P2; 1.7±1.3). No major adverse reaction was observed. Minor adverse effects occurred in 25.0% of cases in group M and 31.9% in group P (NS). The incidence in group P2 (44.4%) was significantly higher than those in group M1 (20.6%) and group P1 (8.3%). Remission rates did not differ between the MMI-treated group (35.0%, n=20) and PTU-treated group (50.0%, n=40). Conclusions: PTU may not be suitable for initial use in children and adolescents with GD, even with the risk of major adverse reactions such as liver failure excluded.

Suppression of sex steroids by a gonadotrophin‐releasing hormone agonist increases serum growth hormone‐binding protein activity in girls with central idiopathic precocious puberty

OBJECTIVE The high‐affinity growth hormone (GH)‐binding protein corresponds to the extracellular domain of GH receptor. The direct role of sex steroids in pubertal bone growth may be an increased GH receptor‐coupled GH action. We examine the GH‐binding protein (GHBP) activity before and after the suppression of female sex steroids and the relation of GHBP to pubertal growth.

A Report of Three Girls with Antithyroid Drug-Induced Agranulocytosis; Retrospective Analysis of 18 Cases Aged 15 Years or Younger Reported between 1995 and 2009

Agranulocytosis is an extremely serious, although rare, adverse effect of antithyroid drugs (ATDs), including methimazole (MMI) and propylthiouracil (PTU), in children and adolescents. There are few reports about the characteristics of ATD-induced agranulocytosis in Japanese children and adolescents. This report presents the cases of three girls with ATD-induced agranulocytosis and a retrospective analysis of 18 patients with ATD-induced agranulocytosis, whose cases had been referred to the drug manufacturer, Chugai Pharmaceutical Co., Ltd. Our 3 patients, ranging in age from 12 to 14 yr, developed ATD-induced agranulocytosis between the 15th and 57th day of ATD treatment for hyperthyroidism. Fever and sore throat were the earliest symptoms of agranulocytosis. The patients were rescued by ceasing ATD therapy and administering antibiotics, potassium iodide, glucocorticoid, immunoglobulin and granulocyte colony-stimulating factor (G-CSF). We retrospectively analyzed 18 cases of ATD-induced agranulocytosis treated with MMI in 16 cases and PTU in 2 cases. Twelve patients were treated with 20–45 mg/d MMI. Agranulocytosis developed between the 15th and 1,344th day of therapy. In conclusion, considering the risk of ATD-induced agranulocytosis, we recommend low-dose MMI therapy for treatment of Graves’ disease.

Higher dose of methimazole causes frequent adverse effects in the management of Graves' disease in children and adolescents.

Abstract Objective: Methimazole (MMI) is used as a first-line antithyroid drug in children and adolescents with Graves’ disease (GD). The aim of this study was to evaluate the correlation between the initial dose of MMI and the clinical course of GD after treatment. Design: Retrospective and collaborative study. Setting: Nine facilities in Chiba prefecture, Japan. Patients: Sixty-four children and adolescents with GD were analyzed. The subjects were divided into three groups by the initial daily dose of MMI: group A, 0.4±0.1 mg/kg (mean±SD, n=11); group B, 0.7±0.2 (n=37); group C, 0.9±0.2 (n=16). Main outcome measures: The duration of time required for normalization of serum free T4 on initial treatment and the incidence of adverse effects for 1 year after the start of MMI were compared. Outcomes were compared among patients who were followed more than 3 years (group A, n=7; group B, n=24; group C, n=12). Results: Mean duration of times for normalization of T4 was 1.9±1.5 months in group A, 1.6±0.9 in group B and 1.9±1.5 in group C (NS). No major adverse reactions were observed. Minor adverse effects occurred in 9.1% of cases in group A, 13.5% in group B and 62.0% in group C (p<0.01). Remission rates did not differ among the three groups. Conclusions: Higher doses of MMI are harmful for initial use in children and adolescents with GD.

Clinical features at diagnosis and responses to antithyroid drugs in younger children with Graves' disease compared with adolescent patients.

Abstract Objective: The aim of this study was to evaluate clinical manifestations, laboratory findings, and effects of antithyroid drugs in younger children with Graves’ disease (GD). Design: A retrospective and collaborative study. Setting: Nine facilities in Chiba prefecture, Japan. Patients: We analyzed 132 children and adolescents with GD. The subjects were divided according to the median age into a group of young children (group I, 4.1–12.4 years, n=66) and an adolescent group (group II, 12.5–15.9 years, n=66). Main outcome measures: Clinical manifestations, laboratory findings, incidence of adverse effects, and remission rates 5 years after initial therapy were assessed. Results: The mean height SD score of group I (1.0) was higher than that of group II (0.3, p<0.001). The mean BMI SD score of group I (–0.7) was lower than that of group II (–0.3, p<0.05). The most common presentations were goiter, sweating, and hyperactivity in group I, whereas the most common presentations were goiter, sweating, and easy fatigability in group II. Hyperactivity was more frequent in group I (56.7%) than in group II (37.9%, p<0.05). Liver dysfunction appeared more often in group I (14.3%) than in group II (1.9%, p<0.05). There was no difference in the appearance of adverse effects between the two groups. The remission rate was slightly lower in group I (23.1%) than in group II (31.3%), but was not significant. Conclusions: Thyrotoxicosis had more influence on the growth and liver function in younger children.