BACKGROUND During COVID‐19 pandemic, the early diagnosis of patients is a priority. Serological assays, in particular IgM and IgG anti‐SARS‐CoV‐2, have today several applications but the interpretation of their results remain an open challenge. Given the emerging role of the IgA isotype in the COVID‐19 diagnostics, we aimed to identify the SARS‐CoV‐2 IgA antibodies in a COVID‐19 population seronegative for IgM. METHODS A total of 30 patients hospitalized in San Giovanni di Dio Hospital (Florence, Italy) for COVID‐19, seronegative for IgM antibodies, have been studied for anti‐SARS‐CoV‐2 antibodies. They all had a positive oro/nasopharyngeal swab reverse transcription polymerase chain reaction result. Assays used were a chemiluminescent assay measuring SARS‐CoV‐2 specific IgM and IgG (S+N) and an ELISA, measuring specific IgG (S1) and IgA antibodies against SARS‐CoV‐2. RESULTS Among the 30 patients, eight were positive for IgA, seven were positive for IgG (N+S) and two for IgG (S1), at first point (5‐7 days from the onset of symptoms). The IgA antibodies mean values at the second (9‐13 days) and third (21‐25 days) time points were even more than twice as high as IgG assays. The agreement between the two IgG assays was moderate (Cohen's K = 0.59; SE = 0.13). CONCLUSIONS The inclusion of the IgA antibodies determination among serological tests of the COVID‐19 diagnostic is recommended. IgA antibodies may help to close the serological gap of the COVID‐19. Variations among anti‐SARS‐CoV‐2 IgG assays should be considered in the interpretation of results. This article is protected by copyright. All rights reserved.

Adequate iodine intake is necessary for normal thyroid function. Iodine deficiency is associated with serious complications, but also iodine excess can lead to thyroid dysfunction, and iodine supplementation aimed to prevent iodine deficiency disorders has been associated with development of thyroid autoimmunity. The epidemiology of thyroid diseases has undergone profound changes since the implementation of iodoprophylaxis, notably by means of iodine-enriched salt, specifically resulting in decreased prevalence of goiter and neonatal hypothyroidism, improved cognitive function development in infancy, and reduced incidence of more aggressive forms of thyroid cancer. The main question we address with this review is the clinical relevance of the possible effect on autoimmunity exerted by the use of iodine-enriched salt to correct iodine deficiency. In animal models, exogenous iodine is able to trigger or exacerbate thyroid autoimmunity, but it is still not clear whether the observed immunological changes are due to a direct effect of iodine on immune response, or whether they represent a secondary response to a toxic effect of iodine on thyroid tissue. Previous iodine status of a population seems to influence the functional thyroid response to increased iodine intake and possibly the development of thyroid autoimmunity. Moreover, the prevalence of thyroid antibodies, regarded as hallmark of autoimmune thyroid disease, varies between populations under the influence of genetic and environmental factors, and the presence of thyroid antibodies does not always coincide with the presence of thyroid disease or its future development. In addition, the incidence of autoimmune diseases shows a general increasing trend in the last decades. For all these reasons, available data are quite heterogeneous and difficult to analyze and compare. In conclusion, available data from long-term population surveys show that a higher than adequate population iodine intake due to a poorly controlled program of iodine prophylaxis could induce thyroid dysfunction, including thyroid autoimmunity mostly represented by euthyroid or subclinical hypothyroid autoimmune thyroiditis. Close monitoring iodine prophylaxis is therefore advised to ensure that effects of both iodine deficiency and iodine excess are avoided.

We identified nine patients from four unrelated families harboring three biallelic variants in SCN1B (NM_001037.5: c.136C>T; p.[Arg46Cys], c.178C>T; p.[Arg60Cys], and c.472G>A; p.[Val158Met]). All subjects presented with early infantile epileptic encephalopathy 52 (EIEE52), a rare, severe developmental and epileptic encephalopathy featuring infantile onset refractory seizures followed by developmental stagnation or regression. Because SCN1B influences neuronal excitability through modulation of voltage‐gated sodium (NaV) channel function, we examined the effects of human SCN1BR46C (β1R46C), SCN1BR60C (β1R60C), and SCN1BV158M (β1V158M) on the three predominant brain NaV channel subtypes NaV1.1 (SCN1A), NaV1.2 (SCN2A), and NaV1.6 (SCN8A). We observed a shift toward more depolarizing potentials of conductance–voltage relationships (NaV1.2/β1R46C, NaV1.2/β1R60C, NaV1.6/β1R46C, NaV1.6/β1R60C, and NaV1.6/β1V158M) and channel availability (NaV1.1/β1R46C, NaV1.1/β1V158M, NaV1.2/β1R46C, NaV1.2/β1R60C, and NaV1.6/β1V158M), and detected a slower recovery from fast inactivation for NaV1.1/β1V158M. Combined with modeling data indicating perturbation‐induced structural changes in β1, these results suggest that the SCN1B variants reported here can disrupt normal NaV channel function in the brain, which may contribute to EIEE52.

Atypical teratoid/rhabdoid tumors (AT/RTs) in the rhabdoid tumor predisposition syndromes are most often caused by germline mutations of the SMARCB1 gene located in chromosome 22q11.2. Although rarely, it can also result from the constitutional ring chromosome 22 (r22): during mitosis the ring chromosome may lead to an increased rate of somatic mutations, resulting in rhabdoid tumor predispositions when the tumor-suppressor gene SMARCB1 is involved. Individuals with r22 may present similar features as those with Phelan-McDermid syndrome (PMDS) due to 22q13.3 deletion, including the SHANK3 gene. Despite several reports on AT/RT in children with r22 and/or PMDS have been published, the role of constitutional r22 as new oncogenic mechanism for AT/RT is still under investigation. There is not a lot of data available on therapeutic and prognostic implications of r22 in AT/RT and PMDS. Herein, we present the first case of a child with constitutional r22, PMDS and AT/RT of the brain, who is a long term survivor and is been treated with growth hormone. We also describe an unexpected adverse reaction to midazolam.

BRAF inhibitors, in recent years, have played a central role in the disease control of unresectable BRAF-mutated pediatric low-grade gliomas (LGGs). The aim of the study was to investigate the acute and long-term effects of vemurafenib on the lipid metabolism in children treated for an LGG. In our cohort, children treated with vemurafenib (n = 6) exhibited alterations in lipid metabolism a few weeks after starting, as was demonstrated after 1 month (n = 4) by the high plasma levels of the total cholesterol (TC = 221.5 ± 42.1 mg/dL), triglycerides (TG = 107.8 ± 44.4 mg/dL), and low-density lipoprotein (LDL = 139.5 ± 51.5 mg/dL). Despite dietary recommendations, the dyslipidemia persisted over time. The mean lipid levels of the TC (222.3 ± 34.7 mg/dL), TG (134.8 ± 83.6 mg/dL), and LDL (139.8 ± 46.9 mg/dL) were confirmed abnormal at the last follow-up (45 ± 27 months, n = 6). Vemurafenib could be associated with an increased risk of dyslipidemia. An accurate screening strategy in new clinical trials, and a multidisciplinary team, are required for the optimal management of unexpected adverse events, including dyslipidemia.