Metabolic and other morbid complications in congenital generalized lipodystrophy type 4.

Morbidity and mortality rates in patients with autosomal recessive, congenital generalized lipodystrophy type 4 (CGL4), an ultra-rare disorder, remain unclear. We report on 30 females and 16 males from 10 countries with biallelic null variants in CAVIN1 gene (mean age, 12 years; range, 2 months to 41 years). Hypertriglyceridemia was seen in 79% (34/43), hepatic steatosis in 82% (27/33) but diabetes mellitus in only 21% (8/44). Myopathy with elevated serum creatine kinase levels (346-3325 IU/L) affected all of them (38/38). 39% had scoliosis (10/26) and 57% had atlantoaxial instability (8/14). Cardiac arrhythmias were detected in 57% (20/35) and 46% had ventricular tachycardia (16/35). Congenital pyloric stenosis was diagnosed in 39% (18/46), 9 had esophageal dysmotility and 19 had intestinal dysmotility. Four patients suffered from intestinal perforations. Seven patients died at mean age of 17 years (range: 2 months to 39 years). The cause of death in four patients was cardiac arrhythmia and sudden death, while others died of prematurity, gastrointestinal perforation, and infected foot ulcers leading to sepsis. Our study highlights high prevalence of myopathy, metabolic abnormalities, cardiac, and gastrointestinal problems in patients with CGL4. CGL4 patients are at high risk of early death mainly caused by cardiac arrhythmias.

Distal Arthrogryposis with Impaired Proprioception and Touch: A Novel Variant in PIEZO2 Gene in Omani Patients and a Genotype-Phenotype Review from a Single-Center Experience.

Distal arthrogryposis with impaired proprioception and touch (DAIPT) is an autosomal recessive neurogenetic disorder caused by homozygous pathogenic variants in the PIEZO2 gene. Here we present four Omani families with multiple affected members with DAIPT. The genetic diagnosis was established by whole exome sequencing and we identified a previously unreported homozygous missense variant PIEZO2 : c.1591T > C, P.(Trp531Arg) in one family with two affected members. All patients showed clinical manifestation shortly after birth including transient respiratory insufficiency, significant hypotonia, and gross motor developmental delay with preserved cognitive function. The skeletal manifestation including arthrogryposis is more pronounced with age as we saw in our older patient. This case report will be of importance for physicians and genetic counsellors for faster diagnosis and for offering carrier testing for at-risk family members as part of the premarital testing program, which could help in reducing the burden of this disorder.

Spondylo-ocular Syndrome Due to a Novel Variant in XYLT2 in an Omani Patient.

Spondylo-ocular syndrome (SOS) is a rare autosomal recessive disorder and affects primarily ocular and spinal tissues. This case report presented an Omani child with a novel homozygous variant, c.2070 G > A (p.Trp690Ter) in XYLT2 associated with SOS for the first time. Oman and other Middle East countries have a high consanguine marriage rate. Our case report will increase knowledge of SOS syndrome to be able to provide genetic diagnosis and counseling for other family members and families as well as prenatal diagnostics for the future pregnancies.