Hypergonadotropic Hypogonadism Due to Transaldolase Deficiency: Two Cases and Literature Review.

Transaldolase deficiency is a rare autosomal recessive inborn error of carbohydrate metabolism caused by pathogenic/likely pathogenic biallelic mutations in the TALDO1 gene. This disorder is characterized by multisystem involvement with variable phenotypes, including intrauterine growth restriction; dysmorphic features; abnormal skin; hepatosplenomegaly; cytopenia; and cardiac, renal, and endocrine abnormalities. Herein, we present two Emirati patients with hypergonadotropic hypogonadism due to transaldolase deficiency and variable phenotypes of systemic involvement.

Rare Coexistence of Acute Intermittent Porphyria With Systemic Lupus Erythematous: Case Report and Literature Review.

Porphyrias, particularly acute intermittent porphyria (AIP), are rare, inherited disorders of heme synthesis. On the other hand, systemic lupus erythematosus (SLE) is an uncommon autoimmune disease that affects women predominantly. The coexistence of AIP and SLE is rare. We report a case of concomitant diagnosis of AIP and SLE in a 21-year-old woman who presented with recurrent acute abdominal, chest, and back pain associated with nausea and vomiting, followed by arthralgia, multiple joint pain, and rash. Investigations revealed severe hyponatremia related to SIADH (syndrome of inappropriate antidiuretic hormone secretion) with a positive SLE antibody panel and a positive urine screen for porphobilinogen. Molecular test confirmed the diagnosis of AIP with a pathogenic mutation in the HMBS gene.

The clinical and genetic spectrum of autosomal-recessive TOR1A-related disorders.

In the field of rare diseases, progress in molecular diagnostics led to the recognition that variants linked to autosomal-dominant neurodegenerative diseases of later onset can, in the context of biallelic inheritance, cause devastating neurodevelopmental disorders and infantile or childhood-onset neurodegeneration. TOR1A-associated arthrogryposis multiplex congenita 5 (AMC5) is a rare neurodevelopmental disorder arising from biallelic variants in TOR1A, a gene that in the heterozygous state is associated with torsion dystonia-1 (DYT1 or DYT-TOR1A), an early-onset dystonia with reduced penetrance. While 15 individuals with AMC5-TOR1A have been reported (less than 10 in detail), a systematic investigation of the full disease-associated spectrum has not been conducted. Here, we assess the clinical, radiological and molecular characteristics of 57 individuals from 40 families with biallelic variants in TOR1A. Median age at last follow-up was 3 years (0-24 years). Most individuals presented with severe congenital flexion contractures (95%) and variable developmental delay (79%). Motor symptoms were reported in 79% and included lower limb spasticity and pyramidal signs, as well as gait disturbances. Facial dysmorphism was an integral part of the phenotype, with key features being a broad/full nasal tip, narrowing of the forehead and full cheeks. Analysis of disease-associated manifestations delineated a phenotypic spectrum ranging from normal cognition and mild gait disturbance to congenital arthrogryposis, global developmental delay, intellectual disability, absent speech and inability to walk. In a subset, the presentation was consistent with foetal akinesia deformation sequence with severe intrauterine abnormalities. Survival was 71%, with higher mortality in males. Death occurred at a median age of 1.2 months (1 week-9 years), due to respiratory failure, cardiac arrest or sepsis. Analysis of brain MRI studies identified non-specific neuroimaging features, including a hypoplastic corpus callosum (72%), foci of signal abnormality in the subcortical and periventricular white matter (55%), diffuse white matter volume loss (45%), mega cisterna magna (36%) and arachnoid cysts (27%). The molecular spectrum included 22 distinct variants, defining a mutational hotspot in the C-terminal domain of the Torsin-1A protein. Genotype-phenotype analysis revealed an association of missense variants in the 3-helix bundle domain to an attenuated phenotype, while missense variants near the Walker A/B motif as well as biallelic truncating variants were linked to early death. In summary, this systematic cross-sectional analysis of a large cohort of individuals with biallelic TOR1A variants across a wide age-range delineates the clinical and genetic spectrum of TOR1A-related autosomal-recessive disease and highlights potential predictors for disease severity and survival.

Severe Prolonged SGLT2i-induced Euglycemic Diabetic Ketoacidosis Refractory to Standard Therapy and Dialysis: Case Report and Literature Review.

Sodium-glucose cotransporter type 2 inhibitors (SGLT2i) are oral hypoglycemic agents that have insulin-independent glucose-lowering effects mediated by increasing the renal excretion of glucose by inhibiting the SGLT2-mediated renal glucose reabsorption. An increasingly recognized complication induced by SGLT2i is euglycemic diabetic ketoacidosis (eDKA). Here, we describe the case of a 26-year-old male patient with type 2 diabetes mellitus and morbid obesity. Prior to presentation he was on multiple oral hypoglycemic agents including SGLT2i. He developed life-threatening severe prolonged eDKA associated with SGLT2i (Canagliflozin), precipitated by adenovirus infection. The acidosis was not responding to standard DKA therapy and renal replacement therapy but was managed effectively with insulin titration based on capillary ketone measurements. After reviewing the literature on severe prolonged eDKA induced by SGLT2 and treatment modalities used, we present previously reported cases similar to ours.

Combining exome/genome sequencing with data repository analysis reveals novel gene-disease associations for a wide range of genetic disorders.

PURPOSE: Within this study, we aimed to discover novel gene-disease associations in patients with no genetic diagnosis after exome/genome sequencing (ES/GS). METHODS: We followed two approaches: (1) a patient-centered approach, which after routine diagnostic analysis systematically interrogates variants in genes not yet associated to human diseases; and (2) a gene variant centered approach. For the latter, we focused on de novo variants in patients that presented with neurodevelopmental delay (NDD) and/or intellectual disability (ID), which are the most common reasons for genetic testing referrals. Gene-disease association was assessed using our data repository that combines ES/GS data and Human Phenotype Ontology terms from over 33,000 patients. RESULTS: We propose six novel gene-disease associations based on 38 patients with variants in the BLOC1S1, IPO8, MMP15, PLK1, RAP1GDS1, and ZNF699 genes. Furthermore, our results support causality of 31 additional candidate genes that had little published evidence and no registered OMIM phenotype (56 patients). The phenotypes included syndromic/nonsyndromic NDD/ID, oral-facial-digital syndrome, cardiomyopathies, malformation syndrome, short stature, skeletal dysplasia, and ciliary dyskinesia. CONCLUSION: Our results demonstrate the value of data repositories which combine clinical and genetic data for discovering and confirming gene-disease associations. Genetic laboratories should be encouraged to pursue such analyses for the benefit of undiagnosed patients and their families.