Evaluation of the Patients with the Diagnosis of Pontocerebellar Hypoplasia: A Multicenter National Study

Pontocerebellar hypoplasia (PCH) is a heterogeneous group of neurodegenerative disorders characterized by hypoplasia and degeneration of the cerebellum and pons. We aimed to identify the clinical, laboratory, and imaging findings of the patients with diagnosed PCH with confirmed genetic analysis. We collected available clinical data, laboratory, and imaging findings in our retrospective multicenter national study of 64 patients with PCH in Turkey. The genetic analysis included the whole-exome sequencing (WES), targeted next-generation sequencing (NGS), or single gene analysis. Sixty-four patients with PCH were 28 female (43.8%) and 36 (56.3%) male. The patients revealed homozygous mutation in 89.1%, consanguinity in 79.7%, pregnancy at term in 85.2%, microcephaly in 91.3%, psychomotor retardation in 98.4%, abnormal neurological findings in 100%, seizure in 63.8%, normal biochemistry and metabolic investigations in 92.2%, and dysmorphic findings in 51.2%. The missense mutation was found to be the most common variant type in all patients with PCH. It was detected as CLP1 (n = 17) was the most common PCH related gene. The homozygous missense variant c.419G > A (p.Arg140His) was identified in all patients with CLP1. Moreover, all patients showed the same homozygous missense variant c.919G > T (p.A307S) in TSEN54 group (n = 6). In Turkey, CLP1 was identified as the most common causative gene with the identical variant c.419G > A; p.Arg140His. The current study supports that genotype data on PCH leads to phenotypic variability over a wide phenotypic spectrum.

Bi-allelic truncating variants in CASP2 underlie a neurodevelopmental disorder with lissencephaly

Lissencephaly (LIS) is a malformation of cortical development due to deficient neuronal migration and abnormal formation of cerebral convolutions or gyri. Thirty-one LIS-associated genes have been previously described. Recently, biallelic pathogenic variants in CRADD and PIDD1, have associated with LIS impacting the previously established role of the PIDDosome in activating caspase-2. In this report, we describe biallelic truncating variants in CASP2, another subunit of PIDDosome complex. Seven patients from five independent families presenting with a neurodevelopmental phenotype were identified through GeneMatcher-facilitated international collaborations. Exome sequencing analysis was carried out and revealed two distinct novel homozygous (NM_032982.4:c.1156delT (p.Tyr386ThrfsTer25), and c.1174 C > T (p.Gln392Ter)) and compound heterozygous variants (c.[130 C > T];[876 + 1 G > T] p.[Arg44Ter];[?]) in CASP2 segregating within the families in a manner compatible with an autosomal recessive pattern. RNA studies of the c.876 + 1 G > T variant indicated usage of two cryptic splice donor sites, each introducing a premature stop codon. All patients from whom brain MRIs were available had a typical fronto-temporal LIS and pachygyria, remarkably resembling the CRADD and PIDD1-related neuroimaging findings. Other findings included developmental delay, attention deficit hyperactivity disorder, hypotonia, seizure, poor social skills, and autistic traits. In summary, we present patients with CASP2-related ID, anterior-predominant LIS, and pachygyria similar to previously reported patients with CRADD and PIDD1-related disorders, expanding the genetic spectrum of LIS and lending support that each component of the PIDDosome complex is critical for normal development of the human cerebral cortex and brain function.

Pediatric headache and neuroimaging: experience of two tertiary centers

INTRODUCTION

Headache is a frequent complaint in children and adolescents. Decision-making for neuroimaging should take into account the cost and the need for sedation in young children.

AIM

To evaluate the yield of MRI in pediatric headache patients seen in two large tertiary hospitals.

METHODS

Data were retrospectively collected from patient records (n = 613) and neuroimaging reports. Headache was classified according to International Headache Society guidelines.

RESULTS

There were 346 children with imaging studies (MRI n = 281, CT n = 65). Of patients who had at least one MRI study, 29% demonstrated an abnormal finding. Findings altering the management were obtained in 21 (7%) patients: the majority (n = 17, 80%) had headache for less than 3 months. On the other hand, four patients with headache longer than 3 months (19%) and 12 patients with normal neurological examination (57%) had significant MRI results affecting management. None of the children in whom the diagnosis of migraine could be made on clinical grounds (n = 40) had a significant MRI finding.

CONCLUSION

Neuroimaging should be performed selectively in children with headache seen in pediatric neurology clinics, especially in headache of short duration (< 3 months) and features atypical for migraine. A normal neurological examination should not reassure the clinician.

TWO CASES WITH DIFFERENT EPILEPSY TYPE AND DYSMORPHIC FEATURES ASSOCIATED WITH 17q21.31 MICRODELETION SYNDROME

The 17q21.31 microdeletion syndrome is characterized by intellectual disability, epilepsy, facial dysmorphism and friendly behavior. Recently, KANSLJ gene has been considered as a major causal gene for this phenotype. Here we report on two Turkish patients with different seizure types and additional dysmorphic features associated with 17q21.31 microdeletion syndrome. A 4 year-old female patient with generalized tonic-clonic seizures, mild mental retardation, dysmorphic features and friendly behavior and a 14 years-old female with intractable epilepsy, different dysmorphic features, severe mental and motor retardation and self-mutilation were evaluated by array-based comparative genomic hybridization (microarray CGH). Array CGH identified 17q21.31 microdeletion that contains MAP7 CRHR1, KANSLI, PLEKHMI genes in case I and CRHR1, PLEKHM but not KANSLJgenes in case 2. To the best of our knowledge this is the first report of a patient with the 17q21.31 microdeletion which does not encompass KANSLI gene. These data imply another gene or genes causing similar phenotype in this patient.

Hemihyperplasia-multiple lipomatosis syndrome associated with hydrocephalus

Hemihyperplasia-multiple lipomatosis syndrome (HMLS) is characterized by subcutaneous lipomatosis and an asymmetric overgrowth (hemihyperplasia). We report an extremely rare case of HMLS associated with hydrocephalus, emphasizing the clinical features and differential diagnosis.

Multiloculated hydrocephalus of intrauterine-onset: a case report of an unexpected MTHFR A1298C positive test result

Loculated hydrocephalus is a condition in which discrete fluid-filled compartments form in association with the ventricular system of the brain. Multiloculated hydrocephalus is a subgroup of this entity involving more than one segment of the ventricular system. Abnormal descent of the cerebellar components can cause multiloculated hydrocephalus due to various pathogenesis. However, studies report no more than 10% of correlation between cerebellar herniation and hydrocephalus. We report an infant with MTHFR A1298C homozygosity, who had hydrocephalus of intrauterine-onset. Alterations in the folate metabolism might lead to congenital hydrocephalus and there is growing data on the prothrombotic effects of MTHFR polymorphisms. To the best of our knowledge, there has been no reported case of MTHFR A1298C homozygosity and intrauterine-onset multiloculated hydrocephalus as a co-existence in the literature.

Pontocerebellar hypoplasia associated with nevoid hyperpigmentation and dysmorphic findings: a new subtype?

Pontocerebellar hypoplasia consists of a rare heterogeneous group of congenital neurodevelopmental disorders characterized by hypoplasia and atrophy of the cerebellar cortex, dentate and pontine nuclei, and inferior olives. Lineer nevoid hyperpigmentation is a rare skin condition characterized by whorls and streaks of hyperpigmented macules in a reticulate pattern along Blaschko's lines. Herein we present a three year-old male patient with pontocerebellar hypoplasia associated with nevoid hyperpigmentation on the upper part of the body. Besides he has some dysmorphic features including microcephaly, triangular chin, long philtrum, long hand fingers, flexion contracture in all of the distal phalanges of both hands, and strabismus.

Ring chromosome 18 in a child with febrile seizures

Ring chromosomes are uncommon cytogenetic findings but have meanwhile been reported for nearly all human chromosomes. Among the rare observations of ring chromosomes in man, the diagnosis of ring chromosome 18 represents a prominent group. We here describe on the cytogenetic analysis results obtained for a 9 years old male patient of non-consanguineous parents. He had growth and developmental delay, mental and motor retardation, microcephaly, microphtalmia, triangle face, small dysplastic ears, strabismus, epicanthal folds on the left, short stature, cryptorchidism, spasticity, pes equinovarus, pes planus, hypothroidism, stereotypic movements and febrile seizures. Also he had hypomyelinization and multiple hyperintense focuses within the white matter on the MRI. The generalized epileptiform abnormality originated from bilateral Centroparietal region. The metabolic investigations including blood and urine amino acids and lysosomal screening tests were normal. The chromosome analysis identified [46,XY,r(18)/46,XY] in 35% of cells a ring 18 and in 65% of cells normal karyotype in peripheral blood cells examined by standard G-bands by Trypsin using Giemsa (GTG) analysis. The dysmorphic features of the presented patient are discussed to the identification of the genotype-phenotype correlation related to his karyotype.

Pitfalls of mapping a large Turkish consanguineous family with vertical monilethrix inheritance

Monilethrix, a rare autosomal dominant disease characterized by hair fragility and follicular hyperkeratosis, is caused by mutations in three type II hair cortex keratins. The human keratin family comprises 54 members, 28 type I and 26 type II. The phenotype shows variable penetrance and results in hair fragility and patchy dystrophic alopecia. In our study, Monilethrix was diagnosed on the basis of clinical characteristics and microscopic examination in a family with 11 affected members. Haplotype analysis was performed by three Simple Tandem Repeat markers (STR) and KRT86 gene was sequenced for the identification of the disease causing mutation. In the results of this, autosomal dominant mutation (E402K) in exon 7 of KRT86 gene was identified as a cause of Moniltherix in the large family from Turkey.

Henoch-Schönlein purpura in north-eastern Turkey

AIM

To evaluate the epidemiological and clinical findings in children with Henoch-Schönlein purpura (HSP) admitted during a 10-year period, 1995 to 2004, and to compare them with series from other parts of the world.

METHODS

The medical records of all children aged 17 years or less admitted with a diagnosis of HSP to the Department of Pediatrics of Karadeniz Technical University were evaluated retrospectively for epidemiological and clinical features.

RESULTS

Of 116 children, 73 (63%) were boys. The mean (SD) age at presentation was 8.9 (3.7) years and one-third of them were older than 10 years of age. Over half the cases presented between September and January. All patients had the typical skin rash. Gastro-intestinal manifestations were seen in 64 (55.1%) and joint manifestations, common during the early course of the disease, in 73 (62.9%). Two patients required laparatomy, one for acute abdomen and the other for bowel resection owing to intussusception. Renal manifestations were observed in 36 (31%), all within 3 months of initial symptoms, and one patient (0.8%) with nephritic syndrome progressed to end-stage renal disease. Five patients had hypertension without urinary findings. Symptoms recurred in eight patients (6.9%) over a period ranging from 2 to 5 months after complete resolution of symptoms. There was a history of a preceding upper respiratory tract infection in 16 (13.7%) and a streptococcal infection was confirmed by throat culture in 12 of the 42 (28.5%) children at presentation.

CONCLUSION

HSP is generally benign and self-limiting. Hypertension may be seen during the course of the disease without urinary findings. In this area, it seems to affect older children and there is a relatively lower incidence of renal manifestations.