SummaryAlternating between hyper- and hypo-thyroidism may be explained by the simultaneous presence of both types of TSH receptor autoantibodies (TRAbs) – thyroid stimulating autoantibodies (TSAbs) and TSH blocking autoantibodies (TBAbs). It is a very rare condition, particulary in the pediatric age. The clinical state of these patients is determined by the balance between TSAbs and TBAbs and can change over time. Many mechanisms may be involved in fluctuating thyroid function: hormonal supplementation, antithyroid drugs and levels of TSAbs and TBAbs. Frequent dose adjustments are needed in order to achieve euthyroidism. A definitive therapy may be necessary to avoid switches in thyroid function and frequent need of therapeutic changes. We describe an immune-mediated case of oscillating thyroid function in a 13-year-old adolescent. After a short period of levothyroxine treatment, the patient switched to a hyperthyroid state that was only controlled by adding an antithyroid drug.Learning points Autoimmune alternating hypo- and hyper-thyroidism is a highly uncommon condition in the pediatric age.It may be due to the simultaneous presence of both TSAbs and TBAbs, whose activity may be estimated in vitro through bioassays.The clinical state of these patients is determined by the balance between TSAbs and TBAbs and can change over time.The management of this condition is challenging, and three therapeutic options could be considered: I-131 ablation, thyroidectomy or pharmacological treatment (single or double therapy).Therapeutic decisions should be taken according to clinical manifestations and thyroid function tests, independent of the bioassays results.A definitive treatment might be considered due to the frequent switches in thyroid function and the need for close monitoring of pharmacological treatment. A definitive treatment might be considered due to the frequent switches in thyroid function and the need for close monitoring of pharmacological treatment.

• Growth impairment in infants with unrestrictive ventricular septal defects is well documented in literature. • Surgical correction in the first months of life is the current option for most ventricular septal defects, leading to a more favourable growth pattern. • Rapid growth during infancy may be associated with the development of insulin resistance, metabolic syndrome, obesity and cardiovascular disease later in life. What is New: • Literature is inconsistent about catch-up growth velocities after ventricular correction for term infants. • Preterm infants have never been enrolled in previous studies that aimed to establish a pattern of growth after surgery. • This group of children, who underwent a rapid post-surgery catch-up growth that follows a period of failure to thrive, may be at a higher risk of insulin resistance, metabolic syndrome, obesity and cardiovascular disease.

Key Clinical MessageNeonatal diabetes is a monogenic form of diabetes. Herein, we report on a newborn presenting diabetic ketoacidosis at 17 days of life. A KCNJ11 mutation was identified. In such cases, insulin can be replaced by sulfonylurea with a successful metabolic control, as an example of how molecular diagnosis may influence the clinical management of the disorder.

Familial hypercholesterolemia (FH) is one of the most prevalent autosomal dominant inherited disorders. Mutations have been found in at least 3 genes: the low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin type 9 (PCSK9). We report on an Azorean family with FH due to a novel mutation in the LDLR gene across three generations. The index-case was first seen at our endocrinology consultation at 12 years old, because of delayed growth and development. Laboratorial investigations revealed a complete failure of the anterior hypophysis due to a congenital malformation of the sella turcica. A total cholesterol of 313 mg/dL (90 -190 mg/dL) and low-density lipoprotein cholesterol (LDL-C) of 262 mg/dL (<115 mg/dL) was found in routine blood tests. There was a paternal history of hypercholesterolemia, corneal arcus and myocardial infarction at an early age. Screening for mutations in LDLR gene was carried out. İn the affected cases, an intronic heterozygous point mutation (c.818-3C > G) causing a premature termination of transcription (stop codon) was identified.

ECMO, both of whom survived to discharge as did all babies who underwent surgical repair of the CDH. Conclusion There was an 11.1% mortality rate increase amongst the cohort studied when compared with the preceding 5 year block. A notably lower termination rate (28% vs. 50%) could possibly account for this, in addition to associated anomalies as above. Variations in management approach within the team was observed leading to the subsequent formulation of an evidence based protocol to improve care quality and future outcomes as current evidence suggests.