Prevalence of germline mutations in the TSH receptor gene as a cause of juvenile thyrotoxicosis.

AIM: To ascertain the prevalence of germline mutations in the TSH receptor gene as a cause of juvenile thyrotoxicosis (JT) in non-autoimmune patients. TSH receptor gene mutations are not seen in autoimmune-active patients. METHODS: In a nationwide study on JT, 123 patients were re-examined 10 y (range 4 to 21 y) after diagnosis. Two patients with toxic adenoma were excluded. In 25 patients, no TPO, TG or TSH-R antibodies were found. In 17 patients, DNA material was available for TSH receptor gene analysis. The entire TSH receptor gene was sequenced in five patients. TSH receptor "hot spots" for mutations in exon 9 and 10 were sequenced in the remaining 12 patients. RESULTS: A TSH receptor gene germline mutation was identified in only one patient of a total number of 121 patients with JT, of which 17 patients were presumed to have non-autoimmune JT by the lack of thyroid autoantibodies. CONCLUSION: In Denmark the prevalence of germline mutations in the TSH receptor gene is one in 121 patients with JT (0.8%; 95% CI: 0.02-4.6%) and one in 17 patients with presumed non-autoimmune JT (6%; 95% CI: 5.88% (0.15-28.69)).

Prevalence of thyroid peroxidase, thyroglobulin and thyrotropin receptor antibodies in a long-term follow-up of juvenile Graves disease.

OBJECTIVE: To relate the presence of thyroid peroxidase antibodies (TPO ab), thyroglobulin antibodies (Tg ab) and thyrotropin receptor antibodies (TSH-R ab) to the clinical course in a long-term follow-up of patients with juvenile Graves' disease (JGD). DESIGN: Patients with JGD were drawn from a Danish retrospective study and reexamined. RESULTS: A number of 105 patients were reexamined 4-21 years (median 10 years) after diagnosis. Three groups were formed: Gr.1: euthyroid patients with anti-thyroid drug (ATD) cessation more than 12 months before reexamination (n=41). Gr.2: patients still on ATD (n=24). Gr.3: subtotally thyroidectomized patients (n=40). Positive TPO ab titers were found in 75% of the patients. In 13% of the patients the titers were very high: >10,000 U/ml. Positive Tg ab were found in 51%. The prevalence of TPO ab and Tg ab was the lowest in group 3. Stimulating TSH-R ab titers were found in 13%. No patients had blocking TSH-R ab. The prevalence of TSH-R ab was 3% in the euthyroid patients, without surgery performed. 15% in the surgical patients, and 25% in the patients still on ATD. CONCLUSIONS: Many JGD patients were euthyroid at the long-term follow-up in spite of high TPO ab and Tg ab titers. Stimulating TSH-R ab were rare (13%). According to this presence of TPO ab, Tg ab or TSH-R ab does not predict the final outcome of JGD. Further studies are needed.

Long-term follow-Up of an infant with thyrotoxicosis due to germline mutation of the TSH receptor gene (Met453Thr).

UNLABELLED: A 18-year clinical follow-up period in a male patient with a germline TSH-R gene mutation (Met453Thr) is described. Nonautoimmune thyrotoxicosis was diagnosed at the age of 7 months. The patient had exophthalmus, failure to thrive, advanced bone age and no goiter. Long-term antithyroid drug treatment (ATD) was necessary during childhood. At the age of 7 years he developed a goiter. Subtotal thyroidectomy was performed at the age of 9 years, followed by repeated ablative radiotherapy at the age of 9.5-13 years due to a toxic multinodular goiter. After 13 years ATD could be discontinued and the patient was euthyroid until 16 years of age, where L-thyroxine substitution had to be started. The exophthalmus diminished, and had disappeared at the age of 18 years, when CT scan of the orbit was performed. CONCLUSION: TSH-R mutation must be considered in early nonautoimmune thyrotoxicosis. A very aggressive treatment strategy is necessary.

Clinical aspects and treatment of juvenile Graves' disease.

Thyrotoxicosis in childhood and adolescence is a rare disease most frequently due to Graves' disease, but non-autoimmune adenomatous goiters are also found. A strong correlation to HLA class II DRB1*0301 and a protective role of DRB1*0701 has been established in juvenile Graves' disease. The natural course of the disease seem to be remission in many, if enough observation time is allowed. Apart from goiter size and the severity of disease at onset, no certain prognostic factors has yet been identified. The treatment modality chosen is not evidence based, but rather tradition, personal experience and pragmatic handling of cases. Prospective, multicenter studies are still in need to answer the questions asked to ensure rational guidelines and consensus. Such studies should also address the essential problem of compliance, one of the important issues in longterm medical treatment.

HLA class II associations in juvenile Graves' disease: indication of a strong protective role of the DRB1*0701,DQA1*0201 haplotype.

Previous studies have shown that HLA-DRB1*0301 and DQA1*0501 are associated with susceptibility to Graves' disease. Ninety Danish patients with early onset of Graves' disease and 102-192 controls were analyzed for HLA-DR and -DQ to investigate if the same associations exist in the juvenile form of Graves' disease. Both DRB1*0301 and DQA1*0501 were highly significantly increased in the patients with relative risks of 8.0 and 4.6, which are higher than those seen in adults. Stratification showed that DRB1*0301 is more strongly associated than DQA1*0501. Surprisingly, the DRB1*0701,DQA1*0201 haplotype was completely absent from this group of patients, indicating a strong protective role of this haplotype in juvenile Graves' disease.

[Study of children with urinary tract infections. Does intravenous urography play any role?]. / Udredning af børn med urinvejsinfektion. Spiller intravenøs urografi stadig en rolle?

Ninety children referred to hospital with urinary tract infections (UTI) were investigated by intravenous urography (IVU), ultrasonography (US) and 99m-Tc dimercaptosuccinic acid scan (DMSA). Fifty-eight children also had a micturition cystourethrography performed. In 36 (40%) of the children at least one result was abnormal. In 29 children IVU was abnormal, 10 had abnormal US and 16 had abnormal DMSA. Six of the 58 children had vesicoureteric reflux in eight kidneys. In 16 children IVU was the only examination with an abnormal result, and in ten of these the findings were considered important for treatment or prognosis. In conclusion, IVU is an important supplement to US and DMSA in investigation programs for children with UTI. IVU should be performed in cases of renal scarring or dilatation and in children with recurrent infections.

Diagnostic imaging in children with urinary tract infection: the role of intravenous urography.

Ninety children referred to hospital with urinary tract infection (UTI) were investigated by iv urography (IVU), ultrasonography (US) and 99mTc dimercaptosuccinic acid scan (DMSA). Fifty-eight children also underwent micturating cystourethrography (MCUG). In 36 (40%) of the children, at least one result was abnormal. Abnormal findings were found in 29 children with IVU, in 10 with US and in 16 with DMSA. Six of the 58 children had vesicoureteric reflux (VUR) in 8 kidneys. In 16 children, IVU was the only examination with an abnormal result, and in 10 of these the findings were considered important for treatment or prognosis. IVU is an important supplement to US and DMSA in investigation programs for children with UTI. IVU should be performed in cases of renal scars, dilatations or in children with recurrent infections.

Incidence of juvenile thyrotoxicosis in Denmark, 1982-1988. A nationwide study.

The objective of this study was to ascertain the annual incidence density of thyrotoxicosis in children under the age of 15 years in Denmark in 1982-1988. The design was based on computerized hospital registration of patient admittances in all departments of paediatrics and internal medicine of Denmark (Faroe Islands and Greenland excluded). Fifty-six children (48 girls and 8 boys) had a confirmed diagnosis of thyrotoxicosis, giving a national incidence density of 0.79/100,000 person-years. In children aged 0-4 years the incidence was very low (0.1/100,000), with no sex difference. In boys aged 5-9 years a similar low incidence was found, while in boys aged 10-14 years the incidence increased to 0.48/100,000. In girls aged 5-9 years the incidence increased to 0.96/100,000, reaching a maximum of 3.01 in the 10-14-year-old girls. In children of > 4 years of age a female preponderance of 6.7:1 was significant. It is concluded that thyrotoxicosis is a rare disorder in Danish children under the age of 15 years, and the incidence increases with age. Female preponderance is significant from early childhood.

Primary hyperoxaluria type 1: clinical manifestations in infancy and prenatal diagnosis.

A 9-month-old Pakistani boy of consanguineous parents presented with uraemia preceded by pyuria from 5 weeks of age. He had no history of renal calculi or macroscopic haematuria. Renal biopsy revealed severe calcium oxalate deposition in the tubuli and fibrosis of the interstitial tissue. Liver biopsy demonstrated complete absence of alanine: glyoxylate aminotransferase catalytic activity and immunoreactive protein compatible with a diagnosis of primary hyperoxaluria type 1. He died at the age of 11 months, just before liver transplantation was made possible. Fetal liver biopsy in the mother's subsequent pregnancy showed normal enzymatic activity. Early detection and early replacement of the missing enzyme by liver transplantation are considered to be crucial for the survival of severely affected infants with the acute neonatal form of primary hyperoxaluria type 1. Persistent pyuria could be an early sign of renal damage secondary to accumulation of oxalate crystals.