Novel CRLF1 gene mutation in a newborn infant diagnosed with Crisponi syndrome

Accelerating the genetic diagnosis of neurological disorders presenting with episodic apnoea in infancy

Unexplained episodic apnoea in infants (aged ≤1 year), including recurrent brief (<1 min) resolved unexplained events (known as BRUE), can be a diagnostic challenge. Recurrent unexplained apnoea might suggest a persistent, debilitating, and potentially fatal disorder. Genetic diseases are prevalent among this group, particularly in those who present with paroxysmal or episodic neurological symptoms. These disorders are individually rare and challenging for a general paediatrician to recognise, and there is often a delayed or even posthumous diagnosis (sometimes only made in retrospect when a second sibling becomes unwell). The disorders can be debilitating if untreated but pharmacotherapies are available for the vast majority. That any child should suffer from unnecessary morbidity or die from one of these disorders without a diagnosis or treatment having been offered is a tragedy; therefore, there is an urgent need to simplify and expedite the diagnostic journey. We propose an apnoea gene panel for hospital specialists caring for any infant who has recurrent apnoea without an obvious cause. This approach could remove the need to identify individual rare conditions, speed up diagnosis, and improve access to therapy, with the ultimate aim of reducing morbidity and mortality.

Clinical and molecular genetic findings of Crisponi / cold-induced sweating syndrome (CS/CISS) spectrum in patients from Turkey

Crisponi / cold-induced sweating syndrome (CS/CISS) is a rare autosomal recessive disorder characterized by episodic hyperthermia, arthrogryposis, impaired feeding ability, and respiratory distress. The classic CS/CISS is mainly associated with CRLF1 and, rarely, CLCF1. PERCHING syndrome, previously known as CS/CISS type-3 associated with biallelic pathogenic variants in KLHL7, is notable for its few overlapping manifestations. This study presents genotype-phenotype relationships in CS/CISS-like spectrum associated with CRLF1 and KLHL7. Clinical findings of 19 patients from 14 families and four patients from three families were found in association with six different CRLF1 and three different KLHL7 variants, respectively. c.167 T > C and c.713delC of the CRLF1 gene and the c.642G > C of the KLHL7 were novel. The c.708_709delCCinsT allele of CRLF1 was identified in 10 families from the Mardin province of Turkey, underlining that an ancestral haplotype has become widespread. CRLF1-associated phenotypes revealed novel manifestations such as prenatal oligohydramnios, benign external hydrocephalus, previously unreported dysmorphic features emerging with advancing age, severe palmoplantar keratoderma and facial erythema, hypopigmented macules and streaks, and recurrent cardiac arrests. KLHL7 variants presented with glabellar nevus flammeus, blepharophimosis, microcephaly, thin corpus callosum, and cleft palate. Abnormalities of sweating, observed in one patient reported herein, is known to be very rare among KLHL7-related phenotypes. This article is protected by copyright. All rights reserved.

Congenital Trismus From Brainstem Dysgenesis: Case Report and Review of Literature

Trismus refers to any condition inducing limited mouth opening and may present as a result of acquired or congenital pathology. We present the case of a newborn who presented with severe, congenital trismus due to brainstem dysgenesis. We describe the course of his investigations, and a multidisciplinary approach to the management of his care and follow-up. To our knowledge, this is one of the earliest reported cases of congenital trismus attributable to brainstem dysgenesis. A literature review was conducted to provide an overview of the differential pathogenesis as it presents in congenital cases and discuss the complexity of managing congenital trismus due to brainstem dysgenesis in a neonate and infant.

A new Turkish infant with clinical features of CS/CISS1 syndrome and homozygous CRLF1 mutation

Cold-induced sweating syndrome (CISS) is a rare autosomal recessive disorder characterized by profuse sweating at cold environmental temperatures, facial dysmorphism and skeletal features. The infantile presentation of CISS, referred to as Crisponi syndrome (CS), is characterized by facial muscular contractures in response to slight tactile stimuli or during crying, by life-threatening feeding difficulties caused by suck and swallow inabilities, and by intermittent hyperthermia. High febrile crises can lead to death within the first months of life. In preadolescence, surviving patients develop kyphoscoliosis and abnormal sweating. CISS is a genetically heterogeneous disorder caused by mutations in CRLF1 in more than 90 percent of patients (CISS1) and by mutations in CLCF1 in the remaining patients (CISS2). It is now well demonstrated that all patients with an infantile-onset CS will develop CISS, confirming that CS and CISS are not "allelic disorders" but the same clinical entity described at different ages of affected patients. Here we report on a Turkish patient with a phenotype consistent with CS/CISS1 and a nonsense homozygous mutation (c.829C>T, p.R277X) in the CRLF1 gene. This mutation has already been reported in another Turkish patient with CS/CISS1.

Cold induced sweating syndrome with urinary system anomaly association

Mutation in the cytokine receptor-like factor 1 and the cardiotrophin-like cytokine (CRLF1 or CLCF1 genes) phenotypically presents as cold induced sweating syndrome (CISS), which is a rare autosomal recessive disorder. The syndrome is characterized by paradoxical sweating in cold weather, dysmorphic facial features, musculoskeletal deformities, difficulty in feeding, and unexplained recurrent episodes of high-grade fever. We are presenting the first case of CISS with urinary system anomaly, which might relate to CRLF1/CLCF1 complex role in the embryonal nephrogenesis.