Hereditary hypomagnesemia with secondary hypocalcemia caused by a novel mutation in TRPM6 gene

OBJECTIVES

Hereditary hypomagnesemia with secondary hypocalcemia (HSH), which results from variations in the transient receptor potential melastatin 6 (TRPM6) genes, is a rare hereditary cause of extremely low serum magnesium levels. We describe an infant with triggered seizures due to hypomagnesemia and a novel mutation in TRPM6 gene was identified.

CASE PRESENTATION

A 10-month-old boy presented with multidrug resistant seizures, and axial hypotonia due to severe hypomagnesemia. Electroencephalography and neuroimaging of the patient was normal. He had a favorable outcome with magnesium supplement. In this study, the patient underwent clinical exome sequencing (CES) which detected a novel homozygous variant in the TRPM6 gene: NM_017662.5: c.5571-3C>G. After replacing his magnesium orally, he was free from seizures and had an encouraging outcome at the twelfth-month follow-up.

CONCLUSIONS

HSH often presents with developmental issues, treatment-resistant seizures, and increased neuromuscular excitability. Untreated hypomagnesemia can potentially be fatal and severely impair cognitive function. Clinical suspicion is essential for early diagnosis and treatment.

Optic neuritis in Turkish children and adolescents: A multicenter retrospective study

BACKGROUND

Various etiologies may underlie optic neuritis, including autoantibody-mediated disorders described in the last decade. We re-examined demographic, clinical, laboratory features and prognostic factors in pediatric patients with autoimmune optic neuritis according to current knowledge.

METHODS

Cases of pediatric ON from 27 centers in Türkiye diagnosed between 2009 and 2022 were included for retrospective evaluation.

RESULTS

The study included 279 patients, 174 females and 105 males, with a female-to-male ratio of 1.65. The average age at onset was 12.8 ± 3.4 years, and mean follow-up, 2.1 years (range: 1-12.1 years). Patients <10 years old were grouped as "prepubertal" and those ≥10 years old as "others". The diagnoses made at the end of follow-up were multiple sclerosis associated optic neuritis (n = 90, 32.3 %), single isolated optic neuritis (n = 86, 31 %), clinically isolated syndrome (n = 41, 14.7 %), myelin oligodendrocyte glycoprotein antibody associated optic neuritis (n = 22, 7.9 %), and relapsing isolated optic neuritis (n = 18, 6.5 %). Predominant diagnoses were myelin oligodendrocyte glycoprotein antibody associated optic neuritis and acute disseminated encephalomyelitis associated optic neuritis in the prepubertal group and multiple sclerosis associated optic neuritis in the older group. Recurrences were observed in 67 (24 %) patients, including 28 with multiple sclerosis associated optic neuritis, 18 with relapsing isolated optic neuritis, 11 with myelin oligodendrocyte glycoprotein antibody associated optic neuritis, 8 with aquaporin-4 antibody related optic neuritis, and 2 with chronic relapsing inflammatory optic neuropathy. Recurrences were more common among female patients. Findings supporting the diagnosis of multiple sclerosis included age of onset ≥ 10 years (OR=1.24, p = 0.027), the presence of cranial MRI lesions (OR=26.92, p<0.001), and oligoclonal bands (OR=9.7, p = 0.001). Treatment in the acute phase consisted of intravenous pulse methylprednisolone (n = 46, 16.5 %), pulse methylprednisolone with an oral taper (n = 212, 76 %), and combinations of pulse methylprednisolone, plasmapheresis, or intravenous immunoglobulin (n = 21, 7.5 %). Outcome at 12 months was satisfactory, with 247 out of 279 patients (88.5 %) demonstrating complete recovery. Thirty-two patients exhibited incomplete recovery and further combination treatments were applied. Specifically, patients with relapsing isolated optic neuritis and aquaporin-4 antibody related optic neuritis displayed a less favorable prognosis.

CONCLUSION

Our results suggest optic neuritis is frequently bilateral in prepubertal and unilateral in peri‑ or postpubertal patients. Age of onset 10 or older, presence of oligoclonal bands, and brain MRI findings reliably predict the development of multiple sclerosis. The risk of developing multiple sclerosis increases mostly during the second and third years of follow-up. Relapsing isolated optic neuritis remains a separate group where the pathogenesis and outcome remain unclear. Investigation of predisposing and diagnostic biomarkers and long follow-up could help to define this group.

Shared Biological Pathways and Processes in Patients with Intellectual Disability: A Multicenter Study

BACKGROUND

 Although the underlying genetic causes of intellectual disability (ID) continue to be rapidly identified, the biological pathways and processes that could be targets for a potential molecular therapy are not yet known. This study aimed to identify ID-related shared pathways and processes utilizing enrichment analyses.

METHOD

 In this multicenter study, causative genes of patients with ID were used as input for Disease Ontology (DO), Gene Ontology (GO), and Kyoto Encyclopedia of Genes and Genomes enrichment analysis.

RESULTS

 Genetic test results of 720 patients from 27 centers were obtained. Patients with chromosomal deletion/duplication, non-ID genes, novel genes, and results with changes in more than one gene were excluded. A total of 558 patients with 341 different causative genes were included in the study. Pathway-based enrichment analysis of the ID-related genes via ClusterProfiler revealed 18 shared pathways, with lysine degradation and nicotine addiction being the most common. The most common of the 25 overrepresented DO terms was ID. The most frequently overrepresented GO biological process, cellular component, and molecular function terms were regulation of membrane potential, ion channel complex, and voltage-gated ion channel activity/voltage-gated channel activity, respectively.

CONCLUSION

 Lysine degradation, nicotine addiction, and thyroid hormone signaling pathways are well-suited to be research areas for the discovery of new targeted therapies in ID patients.

Sleep problems in adolescents with epilepsy and their caregivers: associations with behavioural difficulties

BACKGROUND

The aim of this study was to investigate the frequency of sleep problems in adolescents with epilepsy and their caregivers. We also examined the behavioural difficulties in adolescents with epilepsy and compared these behaviors with healthy controls.

METHODS

This observational case-control study included 37 adolescents with epilepsy and their caregivers, and 43 healthy age-matched adolescents and their caregivers. The Children`s Sleep Habits Questionnaire (CSHQ), DSM-5 Level 2 Sleep Disorders Scale for Children, and Strengths & Difficulties Questionnaire (SDQ) were used to evaluate sleep habits, sleep problems, and behavioural difficulties in adolescents. The DSM-5 sleep disorder scale for adults was used to evaluate the caregivers` sleep problems.

RESULTS

Adolescents with epilepsy had higher sleep problem scores such as daytime sleepiness and overall sleep problems compared with healthy controls. The psychopathological symptoms such as conduct problems, hyperactivity/inattention, and total behavior were also more frequent in adolescents with epilepsy. There was a nonsignificant increase in DSM-5 sleep disturbance score in caregivers of adolescents with epilepsy. Sleep onset delay had a significant negative correlation with total behavioral difficulties (r = -0.44, p < 0.01), and emotional problems (r = -0.47, p < 0.05) in adolescents with epilepsy. Sleep duration was negatively correlated with conduct problems (r = -0.33, p < 0.05), but positively correlated with prosocial score (r = 0.46, p < 0.01) in adolescents with epilepsy. Night waking was positively correlated with total behavioral difficulties (r = 0.35, p < 0.05) and hyperactivity score (r = 0.38, p < 0.05) in adolescents with epilepsy.

CONCLUSIONS

Adolescents with epilepsy have more frequent sleep disturbances and maladaptive behaviors such as hyperactivity/inattention, and conduct problems compared with healthy controls, and their caregivers are more vulnerable to sleep problems. Moreover, we also demonstrated a strong association between sleep disturbances and behavioral problems in adolescents with epilepsy.

Cerebral sinovenous thrombosis in children: A single-center experience

Objective

The study aimed to evaluate the patients with a diagnosis of cerebral sinovenous thrombosis in terms of clinical findings, etiology and underlying risk factors, imaging findings, treatment, and prognosis in the long term.

Materials and Methods

Medical records of 19 patients whose ages ranged between 0 days and 17 years with clinical and radiological cerebral sinovenous thrombosis in Ege University Department of Child Neurology were retrospectively evaluated.

Results

Nine of nineteen cases were female (47.3%). The median age was 84 months (0-201 months). The most common complaint at the presentation was headache (n=12) and the most common physical examination finding was papilledema (n=11). In etiology, otitis/mastoiditis in three cases, iron deficiency anemia in three cases, sinusitis in two cases, catheter use in four cases, Behçet's disease in three cases were determined. The most common observed genetic factors causing thrombosis was methylenetetrahydrofolate reductase mutation. The transverse sinus (68.4%) is the sinus where thrombosis is most frequently observed. As a result of an average follow-up of 12 months (2-72 months), hemiparesis (n=3/19, 15.7%) and epilepsy (n=5/19, 26.3%) were recorded as sequelae findings, and no mortality was observed.

Conclusion

In cases presenting with headache, evaluation of papilledema on funduscopic examination should not be skipped. Neurological imaging should be performed in the change of consciousness of poor feeding infants and children with infections in the head and neck area or underlying chronic diseases. When cerebral sinovenous thrombosis is detected, anticoagulant therapy should be started immediately.