Expanded phenotypic spectrum of neurodevelopmental and neurodegenerative disorder Bryant-Li-Bhoj syndrome with 38 additional individuals

Bryant-Li-Bhoj syndrome (BLBS), which became OMIM-classified in 2022 (OMIM: 619720, 619721), is caused by germline variants in the two genes that encode histone H3.3 (H3-3A/H3F3A and H3-3B/H3F3B) [1-4]. This syndrome is characterized by developmental delay/intellectual disability, craniofacial anomalies, hyper/hypotonia, and abnormal neuroimaging [1, 5]. BLBS was initially categorized as a progressive neurodegenerative syndrome caused by de novo heterozygous variants in either H3-3A or H3-3B [1-4]. Here, we analyze the data of the 58 previously published individuals along 38 unpublished, unrelated individuals. In this larger cohort of 96 people, we identify causative missense, synonymous, and stop-loss variants. We also expand upon the phenotypic characterization by elaborating on the neurodevelopmental component of BLBS. Notably, phenotypic heterogeneity was present even amongst individuals harboring the same variant. To explore the complex phenotypic variation in this expanded cohort, the relationships between syndromic phenotypes with three variables of interest were interrogated: sex, gene containing the causative variant, and variant location in the H3.3 protein. While specific genotype-phenotype correlations have not been conclusively delineated, the results presented here suggest that the location of the variants within the H3.3 protein and the affected gene (H3-3A or H3-3B) contribute more to the severity of distinct phenotypes than sex. Since these variables do not account for all BLBS phenotypic variability, these findings suggest that additional factors may play a role in modifying the phenotypes of affected individuals. Histones are poised at the interface of genetics and epigenetics, highlighting the potential role for gene-environment interactions and the importance of future research.

A girl with bilateral temporomandibular joint pain, generalized arthralgias, and inability to walk

The authors present the case of a 6.5-year-old girl with bilateral temporomandibular joint (TMJ) pain, generalized arthralgias, inability to walk, and absence of deep tendon reflexes in the context of Guillain-Barrè syndrome. TMJ pain was the sole manifestation for 3 days, before other typical symptoms appeared, an issue that initially led to an improper diagnosis. A thorough clinical examination along with laboratory and radiographic evaluation excluded other possible causes of TMJ pain. To the best of the authors' knowledge, this is the first case of Guillain-Barrè syndrome in the pediatric population initially presenting with bilateral TMJ pain. Guillain-Barrè syndrome may be quite atypical in its expression, especially in young children, with pain being a common presenting symptom, and pediatricians should be alert to avoid misdiagnosis.

Transient decrease in serum albumin concentrations in epileptic children treated with sodium valproate monotherapy

OBJECTIVE

Hypoalbuminemia has been reported in patients with severe disability and epilepsy and in patients with epilepsy treated with short-term sodium valproate (VPA) therapy; however, serum albumin concentrations have not previously been determined in otherwise healthy patients with epilepsy and receiving long-term VPA monotherapy.

METHODS

Serum albumin concentrations were determined in 26 ambulatory children with epilepsy before and at 6, 12, and 24 months of VPA monotherapy. Serum total protein concentrations and serum concentrations of other biochemical markers of liver and renal function such as alanine aminotransferase, aspartate aminotransferase, gamma-glutamyltransferase, and creatinine concentration were also measured in the study participants before and at 6, 12, and 24 months of treatment.

RESULTS

Serum albumin concentrations were reduced at 6 months of treatment (P = 0.007). Serum alanine aminotransferase concentrations were significantly increased at 6 (P = 0.034) and 12 months of treatment (P = 0.046), whereas serum aspartate aminotransferase concentrations were significantly increased at 6 (P = 0.002) and 12 months of treatment (P = 0.002). There were no significant correlations between serum albumin and the other parameters at 6 months of treatment.

CONCLUSIONS

Ambulatory children who receive VPA monotherapy may have early but transient decrease in serum albumin concentrations. Further studies are needed to address this issue and to determine the possible clinical implications and the mechanisms involved in VPA-mediated decrease in serum albumin concentrations.

Moya moya syndrome in a child with pyruvate kinase deficiency and combined prothrombotic factors

A 13-year-old Greek girl with pyruvate kinase deficiency and moya moya angiographic pattern is reported. She also had raised serum lipoprotein (a) concentration and was homozygous for the C677T mutation of the methylenetetrahydrofolate reductase gene. She presented with neonatal onset of anemia, hemolytic and aplastic crises, especially during infections, stroke, and also progressive motor and mental deterioration. A digital cranial angiography at 13 years revealed the typical angiographic findings of moya moya angiopathy. This is likely the first patient with pyruvate kinase deficiency and moya moya syndrome and also the combination of elevated serum lipoprotein (a) concentration and the C677T mutation of the methylenetetrahydrofolate reductase gene to be reported. In patients with pyruvate kinase deficiency and moya moya syndrome, a search for raised serum lipoprotein (a) concentrations and the C677T mutation of the methylenetetrahydrofolate reductase gene should be considered.

Different additional risk factors for cerebral infarctions associated with the factor V Leiden mutation in a family

Several cases with cerebral infarctions associated with the factor V Leiden mutation have been reported. However, bearing in mind the large number of asymptomatic individuals with the factor V Leiden mutation, additional risk factors for cerebral infarctions should be considered. In this report, two siblings with cerebral infarctions associated with a combination of heterozygous factor V Leiden mutation and different additional exogenous and endogenous thrombogenic risk factors are described. Respiratory problems in the perinatal period and increased lipoprotein (a) concentrations in the first patient and an episode of gastroenteritis from Shigella infection and persistent high titers of serum anticardiolipin and beta(2)-glycoprotein I antibodies in the second patient were recorded as additional thrombogenic risk factors. Furthermore, both patients were found to be heterozygous for the methylenetetrahydrofolate reductase gene C677T mutation. These findings suggest that even in the same family, different additional thrombogenic risk factors can be present in infants with cerebral infarctions associated with the factor V Leiden mutation. An extensive search of additional circumstantial and genetic thrombogenic risk factors should be useful for prophylaxis and prognosis of these infants with cerebral infarctions associated with the factor V Leiden mutation and of their related family members. To our knowledge, the second patient in this study is the first patient reported to have cerebral infarctions associated with the combination of the factor V Leiden mutation and persistent high titers of serum beta(2)-glycoprotein I antibodies.

Effect of sodium valproate monotherapy on serum uric acid concentrations in ambulatory epileptic children: a prospective long-term study

PURPOSE

Hyperuricemia has been shown to be related to cardiovascular morbidity and mortality. There is controversial data about the effect of sodium valproate (VPA) monotherapy on serum uric acid concentrations. The purpose of this study was to investigate by a long-term, prospective method, whether treatment with VPA monotherapy may alter serum uric acid concentrations and liver function tests in ambulatory epileptic children.

MATERIAL AND METHODS

Serum uric acid concentrations were determined in 28 ambulatory epileptic children before and at 6, 12 and 24 months of VPA monotherapy. Serum concentrations of biochemical markers of liver and renal function, such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), gamma-glutamyltransferase (gamma-GT) and creatinine (Cr) were also measured before and at 6, 12 and 24 months of VPA monotherapy. Serum VPA concentrations remained within the therapeutic range (50-100 mg/L) during the period of study.

RESULTS

No statistically significant changes in serum uric acid concentrations were found at 6, 12 or 24 months of treatment. Serum ALT concentrations were significantly increased at 6 and 12 months of treatment, AST concentrations at 6 and 12 months of treatment and LDH concentrations at 12 months of treatment.

CONCLUSIONS

VPA monotherapy does not have a significant effect on serum uric acid concentrations in ambulatory epileptic children. Further studies are needed to definitively address whether it would be useful for physicians to routinely check for elevated serum uric acid levels in children treated with VPA.

Early and persistent increase in serum lipoprotein (a) concentrations in epileptic children treated with carbamazepine and sodium valproate monotherapy

PURPOSE

The aim of this study was to investigate by a prospective, self-controlled method, whether treatment with carbamazepine (CBZ) and sodium valproate (VPA) monotherapy may alter serum lipoprotein (a) [Lp(a)] concentrations in epileptic children.

METHODS

Serum Lp(a) concentrations have been determined in 18 epileptic children before and at 6, 12 and 24 months of treatment with CBZ monotherapy and in 30 epileptic children before and at 6, 12 and 24 months of treatment with VPA monotherapy. Serum total cholesterol, triglycerides, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, apolipoproteins A-I and B concentrations and serum concentrations of biochemical markers of liver and renal function were also measured in the study participants.

RESULTS

Serum Lp(a) concentrations were significantly increased at 6, 12 and 24 months of CBZ and VPA monotherapy. There were no significant correlations between serum Lp(a) and serum lipids, lipoproteins, apolipoproteins, concentrations of biochemical markers of liver and renal function or antiepileptic-drugs concentrations.

CONCLUSIONS

Children who receive CBZ or VPA monotherapy may have significant and persistent increase in serum lipoprotein (a) concentrations, occuring early in the course of therapy. It may be useful to measure serum Lp(a) concentrations routinely in epileptic children taking these antiepileptic drugs, especially in those that are already at higher atherosclerotic risk.

Homozygous MTHFR C677T gene mutation and recurrent stroke in an infant

The role of homozygosity for the C677T mutation in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene as an independent risk factor for primary and recurrent stroke has been questioned, although recent data appear to be supportive. However, the association of homozygous C677T MTHFR mutation with silent brain infarctions in infancy has not been reported. The authors describe an 11-month-old male who had suffered a silent brain infarction followed by a symptomatic arterial stroke. The evaluation revealed mildly elevated homocysteine levels secondary to homozygous C677T alleles for MTHFR and iron deficiency anemia. An extensive evaluation for other causes of infarction was negative. We suggest that the mother's homozygous MTHFR status played a role in the early onset of stroke and that iron deficiency anemia may have contributed to the recurrence. The patient was treated with anticoagulation therapy, folic acid, and iron supplementation and has not had a recurrent event during 3 years of follow-up. This case provides further evidence that homozygous MTHFR mutation is a predisposing factor for early and recurrent pediatric stroke, including silent infarcts, especially in the presence of other risk factors.

Early alteration in bone metabolism in epileptic children receiving carbamazepine monotherapy owing to the induction of hepatic drug-metabolizing enzymes

The purpose of this study was to investigate, by a prospective, self-controlled method, whether early treatment with carbamazepine monotherapy can alter bone metabolism in ambulatory epileptic children with adequate sun exposure, based on the determination of total serum alkaline phosphatase and its bone isoenzyme activities. Serum total alkaline phosphatase and its bone, liver, and intestinal isoenzyme activities were evaluated in 22 epileptic ambulatory children (13 males and 9 females, aged from 5 to 12 years) before and at 3, 6, and 12 months of carbamazepine monotherapy. Serum concentrations of other biochemical markers of bone and liver metabolism, such as calcium, phosphorus, magnesium, gamma-glutamyltransferase, alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase, were also measured in the study participants before and at 6 and 12 months of treatment. Carbamazepine was prescribed at normal dosages (16.4-20 mg/kg/day). Serum total alkaline phosphatase activities were significantly increased at 3 (P = .000), 6 (P = .024), and 12 (P = .037) months of treatment; serum bone alkaline phosphatase activities at 3 (P = .000), 6 (P = .008), and 12 (P = .017) months of treatment; and serum liver alkaline phosphatase activities at 3 (P = .000), 6 (P = .049), and 12 (P = .008) months of treatment, whereas serum intestinal alkaline phosphatase isoenzyme activity was significantly increased only at 3 months of treatment (P = .035). Serum gamma-glutamyltransferase activities were also significantly increased at 6 (P = .000) and 12 (P = .000) months of treatment. No significant changes in the concentrations of serum calcium, phosphorus, magnesium, alanine aminotransferase, aspartate aminotransferase, and lactate dehydrogenase were noted at 6 and 12 months of treatment. There was a significant correlation between serum gamma-glutamyltransferase activities and serum total alkaline phosphatase activities (r = .689, P = .000 at 6 months; r = .493, P = .020 at 12 months), bone alkaline phosphatase activities (r = .700, P = .000 at 6 months; r = .466, P = .029 at 12 months), and liver alkaline phosphatase activities (r = .427, P = .047 at 6 months; r = .425, P = .048 at 12 months). These findings indicate that ambulatory children who receive carbamazepine monotherapy, even when residing in a country with adequate sunlight, can have their bone metabolism altered early in the course of treatment, as indicated by the elevated activities of serum bone alkaline phosphatase isoenzyme. This early alteration in bone metabolism is probably due to the hepatic enzyme-inducing character of carbamazepine.

Serum amylase, pancreatic amylase and lipase concentrations in epileptic children treated with carbamazepine monotherapy

BACKGROUND

Serum total amylase and lipase activities have been determined in epileptic patients treated with polytherapy using enzyme-inducing anticonvulsant drugs; however, to our knowledge, serum total amylase, pancreatic amylase and lipase activities have not previously been determined in patients receiving carbamazepine monotherapy. The purpose of this study was to investigate by a prospective, self-controlled method, whether early treatment with carbamazepine monotherapy may alter serum total amylase, pancreatic amylase and lipase concentrations of epileptic children.

METHODS

Serum total amylase, pancreatic amylase and lipase activities have been determined in 18 epileptic children before and at 6 and 12 months of treatment with carbamazepine monotherapy. Serum gamma-glutamyltransferase activities were also determined.

RESULTS

Serum total amylase concentrations were significantly increased at 6 months of treatment (p=0.034), and serum nonpancreatic amylase concentrations were significantly increased at 6 (p=0.016) and 12 months of treatment (p=0.039), whereas serum pancreatic amylase and lipase concentrations did not significantly change at 6 or 12 months of treatment with carbamazepine monotherapy. Furthermore, serum gamma-glutamyltransferase concentrations were significantly increased at 6 (p=0.000) and 12 months of treatment (p=0.000) with carbamazepine monotherapy. There was no significant correlation between serum nonpancreatic amylase concentrations and serum gamma-glutamyltransferase or carbamazepine concentrations at 6 and 12 months of treatment with carbamazepine monotherapy.

CONCLUSIONS

These findings indicate that nonpancreatic amylase concentrations may be increased in patients treated with carbamazepine monotherapy. Therefore, measurement of serum pancreatic amylase and lipase concentrations is suggested in epileptic patients receiving carbamazepine monotherapy with symptoms suggesting pancreatic dysfunction, so that unnecessary discontinuing of treatment with carbamazepine should be avoided.

Non-convulsive status epilepticus associated with tiagabine therapy in children

A case of a 7-year-old male with epilepsy who developed non-convulsive status epilepticus (NCSE) with electroclinical features consistent with those of atypical absence seizures after adjunctive antiepileptic therapy of tiagabine (TGB) is reported. The patient had frequent generalised and rare partial seizures with generalised epileptic discharges on prior electroencephalogram (EEG) recordings. NCSE was developed when rapid dosage increase and high dose of TGB was given. This case emphasises the need for close monitoring of children with epilepsy taking TGB for exacerbation of seizures or development of NCSE.

Acute necrotizing encephalopathy associated with parainfluenza virus in a Caucasian child

Acute necrotizing encephalopathy is a severe parainfectious disorder with a clear racial predilection for Oriental children living in the Far East. The prognosis was originally reported as grave; however, a mild form of the disease has recently been described. A case of parainfluenza virus-associated acute necrotizing encephalopathy in a Caucasian child with a mild clinical course and excellent prognosis is presented. In this patient, the initial clinical picture was not very impressive, and the diagnosis was delayed until the third week of the illness, when neuroimaging was performed. Two months later, clinical and neuroimaging findings had almost completely resolved. Suggested criteria for a benign prognosis, such as normal liver function and cerebrospinal fluid protein levels, asymmetric thalamic lesions, and no brainstem involvement, were relevant in the present case. An extended diagnostic work-up for metabolic, vascular, coagulation, and infectious diseases was negative apart from a seroconversion for parainfluenza virus. To our knowledge, this is the first reported case of acute necrotizing encephalopathy associated with parainfluenza virus infection. Acute necrotizing encephalopathy, especially in the mild form, might not be fully recognized and could be underdiagnosed in Europe, where the reported incidence of the syndrome is very low.

Congenital asymmetric crying facies and agenesis of corpus callosum

Although association of congenital asymmetric crying facies (CACF) with major congenital anomalies of central nervous system (CNS) has been described, brain magnetic resonance imaging (MRI) studies have not been reported. Two children who had CACF associated with agenesis of corpus callosum (ACC) diagnosed by MRI are described. Neurofibromatosis type 1 (NF-1) was diagnosed in one case. Both patients had developmental delay. To the best of our knowledge, only one previous case with CACF associated with ACC has been reported, but our cases are the first cases reported with the characteristic findings of ACC on MRI. Although café-au-lait spots have been described in previous cases, the coexistence of CACF and NF-1 has not previously been reported. Although these associations may be coincidental, clinicians should be aware of the potential link between these entities. Furthermore, these findings emphasize the importance of MRI studies for detecting brain anomalies in cases with CACF and suspected CNS involvement.

Congenital microcephaly in two infants with the factor V Leiden mutation

Two infants with congenital microcephaly associated with the factor V Leiden mutation are described. In both cases, brain magnetic resonance imaging (MRI) revealed cerebral atrophy and porencephalic cystic lesions, which were probably attributable to prenatal cerebral vascular events. These findings suggest that assessment for this mutation is an important part of the evaluation of infants with unexplained congenital microcephaly, especially in cases with infarcts and/or porencephalic cysts on brain MRI.

Infantile progressive bulbar palsy with deafness

A 12-month-old boy with progressive cranial nerve palsies followed by ventilatory failure demanding artificial ventilation, generalized muscle weakness, and rapid progression to death at the age of 21 months is described. The patient had normal early development and also apparently normal hearing at presentation of illness but, after 6 months of the onset of the disease, hearing loss was documented by brainstem auditory evoked potentials (BAEP). Although the initial clinical and laboratory findings of this infant could fit with the diagnosis of progressive childhood bulbar palsy or Fazio-Londe (FL) disease, the subsequent appearance of hearing loss suggests that this patient represents a case of progressive bulbar palsy with perceptive deafness or Brown-Vialetto-Van Laere (BVVL) syndrome. To our knowledge, this case of BVVL syndrome with severe clinical features and rapid deterioration leading to death is the youngest one reported in the literature. Furthermore, this case emphasizes the need for repeated auditory examinations, including the performance of BAEP in all cases, especially infants and young children with progressive bulbar palsy.

Long-term findings on brain magnetic resonance imaging in acute encephalopathy with bilateral striatal necrosis associated with measles

The long-term findings on brain magnetic resonance imaging (MRI) in a 7 10/12-year-old boy with a history of acute encephalopathy with bilateral striatal necrosis following measles at the age of 22 months are described. At the early stage of illness, brain MRI studies revealed bilateral, symmetric basal ganglia lesions, predominant on the globi pallidi, appearing as hyperintense signals on T1- and T2-weighted images. Six years later, follow-up brain MRI studies showed that the bilateral, symmetric lesions on the globi pallidi persisted with low signal on T1- and high signal on T2 weighted images. At present, the patient has some persistent neurologic signs. These findings suggest that both clinical and neuroradiologic findings may persist in children with acute encephalopathy with bilateral striatal necrosis following measles.

Acute disseminated encephalomyelitis associated with parainfluenza virus infection of childhood

Acute disseminated encephalomyelitis associated with the parainfluenza virus has rarely been reported in childhood. A 2.5-year-old girl with acute disseminated encephalomyelitis, who developed bilateral symmetrical lesions in the basal ganglion, thalamus, corpus callosum, cerebral subcortical white matter, and cerebellar medulla on brain magnetic resonance imaging is described. Serological confirmation of parainfluenza virus infection was made 2 weeks following the onset of neurological symptoms. Four months later, the patient had a full recovery. At present, 3 years later, no relapse has been reported and she is leading a normal life. Our case is of interest because of its rarity, the striking brain magnetic resonance imaging, and the good neurological outcome.

Brain MRI findings in influenza A-associated acute necrotizing encephalopathy of childhood

Acute necrotizing encephalopathy following influenza A is frequently reported from Japan and Taiwan but is very rarely seen in Western countries. We describe a 10-year-old boy with acute necrotizing encephalopathy, who developed symmetrical thalamic and brain stem lesions seen on magnetic resonance imaging (MRI). Serological confirmation of influenza A was made 2 weeks after the onset of symptoms. The child made a full recovery. This case is interesting because of its rarity in European countries, the striking brain MRI findings and the good neurological outcome.