No abstract

Maternal hyperthyroidism implies the risk of thyroid abnormalities in the newborn. We describe retrospectively the clinical presentation, treatment and follow up of 28 children born of hyperthyroid mothers. Patients were subdivided as follows: Group A (neonatal hyperthyroidism) (n=9): born from eight hyperthyroid mothers and one thyroidectomized mother. Children born from untreated mothers consulted between 1 and 7 days of life, while those born from treated mothers consulted between 8 and 17 days. Eight needed treatment. All remitted completely. Group B (primary hypothyroidism) (n=14): born from treated mothers, detected by neonatal screening. Eleven had transient hypothyroidism and three needed treatment. Group C (hypothalamic-pituitary hypothyroidism) (n=5): born from uncontrolled hyperthyroid mothers and found during follow up (age 9-28 days). The infants were treated with thyroid hormone, and recovered before 8 months of life. Every child born from a mother with autoimmune thyroid disease needs paediatric endocrinological assessment for detection of possible thyroid disorders.

Introduction: We retrospectively assessed the incidence of congenital hypothyroidism (CH) detected through our neonatal screening program between 1997 and 2010. We describe the diagnostic characteristics of the detected population and verify the impact of a TSH cutoff (CO) change. Patients and Methods: Screening was based on TSH determination on dried blood spot on filter paper samples (IFMA) using a 15 mU/l blood CO until 12/2002 (P1) and 10 mU/l thereafter (P2). Patients were classified as having transient or permanent CH (athyreotic, ectopic, eutopic, with goiter and unknown etiology). Global and diagnostic-related incidences were calculated for the whole studied period with the same CO, and P1 and P2 were compared. Results: Incidences of permanent CH were 1:3,108 (P1) and 1:2,367 (P2). The lower CO detected 22 extra CH, 13 of them definitive (70% with eutopic glands). Only a significant increase (p < 0.05) in eutopic CH was found, partially related to the lower CO applied. A statistically significant association with time was seen for total definitive and ectopic cases (p < 0.05). Conclusion: Our findings revealed some changes in the detected population partially related to the CO applied, with only eutopic dysfunctional disorders being more prevalent in the later years. Total permanent CH and ectopic thyroid disorders showed a trend toward higher detection over time, but their prevalence has not changed significantly in our screening program.

Objective: To evaluate the influence of gestational age (GA) and birth weight (BW) on 17α-OH-progesterone (17-OHP) levels with respect to their impact on the recall rate of neonatal screening programs for congenital adrenal hyperplasia (CAH). Patients and Methods: In June 1997 we began a pilot screening program for CAH measuring 17-OHP using a fluoroimmunoassay method (DELFIA) on dried blood spots. Until September 1999, 24,153 babies were screened. Among them, we analyzed the levels of 17-OHP in 1,313 samples from healthy preterm babies (23–36 weeks) and 1,500 term babies (>37 weeks), grouped according to GA and BW. All preterm babies underwent another sampling in their 2nd week of life. Results: 5 CAHs were detected. The 30-nmol/l cutoff limit for 17-OHP in blood corresponded to the calculated 99th percentile in term newborns, while in preterm babies higher levels were found. GA and BW correlated inversely with 17-OHP levels. Conclusion: GA and BW were useful tools to adjust cutoff levels, obtaining a significant reduction in follow-up testing and psychological stress for families. The high false-positive recall rate in preterm babies can be substantially lowered with adjusted GA and/or BW criteria.

Background/Aim: Congenital hypothyroidism (CH) is a heterogeneous entity. Neonatal screening programs based on thyrotropin (TSH) determination allow primary CH diagnosis but miss central CH (CCH). CCH causes morbidity, alerts to other pituitary deficiencies, and is more prevalent than previously thought. We aimed at developing a pilot neonatal screening program for CCH detection. Patients and Methods: A prospective 2-year pilot neonatal screening study based on simultaneous dried blood specimen TSH and thyroxine (T₄) measurements was implemented in term newborns aged 2–7 days. Those with T₄ ≤4.5 µg/dL (–2.3 SDS) and TSH <10 mIU/L were recalled (suspicious of CCH) and underwent clinical and biochemical assessment performed by expert pediatric endocrinologists. Results: A total of 67,719 newborns were screened. Primary CH was confirmed in 24 (1: 2,821). Forty-four newborns with potential CCH were recalled (recall rate 0.07%) at a mean age of 12.6 ± 4.8 days. In this group, permanent CCH was confirmed in 3 (1: 22,573), starting L-T₄ treatment at a mean age of 12.3 ± 6.6 days; 14 boys showed T₄-binding globulin deficiency (1: 4,837); 24 had transient hypothyroxinemia (21 non-thyroidal illness and 3 healthy); and 3 died before the confirmation stage. According to initial free T₄ measurements, CCH patients had moderate hypothyroidism. Conclusions: Adding T₄ to TSH measurements enabled the identification of CCH as a prevalent condition and contributed to improving the care of newborns with congenital hypopituitarism and recognizing other thyroidal disorders.

PAE was found to be a minimally invasive, highly successful and safe technique for the management of PPH. It should be considered in PPH refractory to initial treatment.

Background: Congenital isolated thyrotropin (TSH) deficiency is an unusual condition characterized by low levels of thyroid hormones and TSH, usually presenting early typical signs of severe hypothyroidism. Five different β-TSH mutations have been described so far. While 4 of them affect only consanguineous families, a frameshift mutation in exon 3 (C105fs114X) has been found also in nonconsanguineous families. Objective: The aim of the present study was to characterize β-TSH mutations in Argentinean patients with congenital central hypothyroidism (CCH) and to emphasize the importance of early biochemical and molecular diagnosis of this disorder. Patients and Methods: We investigated 8 Argentinean children (3 boys, 5 girls) from 7 unrelated families with CCH based upon low levels of T₄ and T₃, and low basal and stimulated TSH levels. Mutation characterizations for the β-TSH gene were performed by PCR amplification followed by sequence and restriction enzyme analysis with SnaBI in the patients, 9 parents and in 100 newborn children. Results: All patients presented the same homozygous mutation in exon 3 of the β-TSH gene (C105fs114X), the 9 studied parents were heterozygous for the same mutation and 1 carrier was found in the 100 studied newborns. Conclusion: Our findings show that the C105fs114X mutation is prevalent in our population and may constitute a hot spot at codon 105 in the β-TSH gene. Since this mutation is easily demonstrable by a SnaBI digestion in DNA amplified from dried blood spots, its investigation would be indicated in patients in our milieu with clinical and biochemical features of CCH, allowing early L-thyroxine (LT₄) replacement and genetic counseling of the family.

Introduction: Current WHO guidelines consider that under adequate iodine intake <3% of newborns should have neonatal TSH levels of >5 mU/l blood when screening is performed in cord blood or at 3 days to 3 weeks of age. Objective: To estimate whether this absolute criterion when applied to newborns older than 48 h of age and native to Buenos Aires coincides with the traditional ones (goiter and urinary iodine in school-age children (SAC)), and if the evaluation varies with either the methodology used for TSH measurements and/or the time of specimen sampling. Population and Methods: TSH was measured by an immunofluorometric assay (IFMA) on filter paper blood spots of 186 cord blood samples, 112 babies <48 h of age and 1,500 newborns >48 h of age, and by immunoradiometric assay (IRMA) in 238 newborns. The WHO ICCIDD absolute criteria were applied to each population. Thyroid volume was assessed by direct palpation in 500 SAC, and in 100 of them urinary iodine levels were measured. Results: TSH levels were >5 mU/l blood in 11.3% of the cord blood samples and in 3.6% of the samples from babies <48 h of age, suggesting mild iodine deficiency. TSH was >5 mU/l in 2.7% of newborns >48 h of age tested by IFMA (iodine sufficient) and in 30% measured by IRMA (moderate iodine insufficiency). Median urinary iodine and goiter prevalence in SAC were 143 µg/l and 4.5%, respectively, as expected in an iodine-sufficient area. Conclusion: The TSH levels in Buenos Aires conform with the WHO criterion that defines iodine sufficiency. Application of this criterion, however, to cord blood samples or samples from babies <48 h old and the use of different methodologies may lead to erroneous conclusions.