Whole exome sequencing identifies a novel variant causing cockayne syndrome type I in a consanguineous Pakistani family

BACKGROUND

Cockayne syndrome (CS) is a rare neurodegenerative disorder characterized by impaired neurological functions, cachectic dwarfism, microcephaly and photosensitivity. Complementation assays identify two groups of this disorder, CS type I (CSA) and CS type II (CSB), caused by mutations in ERCC8 and ERCC6, respectively.

OBJECTIVES

This study aimed to investigate the genetic basis of a consanguineous Pakistani family with three affected individuals presenting with typical clinical symptoms of CS.

METHODS

We employed whole exome sequencing of the proband and then Sanger sequenced all the family members to confirm its segregation in the family. Different bioinformatics tools were used to predict pathogenicity of this variant.

RESULTS

Variants were filtered according to the pedigree structure. We identified a novel homozygous variant (c.202A>T; p.Ile68Phe) in ERCC8 gene in the proband. The variant was found to segregate in the family.

CONCLUSIONS

These findings add to the genetic heterogeneity of ERCC8 and expands the mutation spectrum. Also, identification of this variant can facilitate prenatal diagnosis/genetic counselling set ups in Pakistan where this disease largely remains undiagnosed.

Real-world comparison of terlipressin vs. octreotide as an adjuvant treatment in the management of variceal bleeding

Variceal bleeding is a major complication and the leading cause of death in patients with cirrhosis and portal hypertension. This study aims to compare the efficacy and safety of terlipressin vs octreotide as an adjuvant to endoscopic management of patients with esophageal variceal bleeding in a real-time scenario. We reviewed the medical records of patients with esophageal variceal bleeding from January 2005 to December 2020 at our tertiary care Aga Khan University Hospital. Mortality was assessed after 6 weeks. A total of 842 patients with variceal bleed were evaluated. 624 patients (74.1%) and 218 patients (25.9%) received Terlipressin and Octreotide respectively. On multiple regression analysis, cardiac events during hospital stay (OR: 11.22), presence of Porto-systemic encephalopathy (OR: 3.79), and elevated bilirubin levels at the time of presentation were found to be independent risk factors for increased six weeks mortality. Moreover, cardiac events during hospital stay (OR: 3.26), Porto-systemic encephalopathy at presentation (OR: 3.06), and octreotide administration (OR: 1.80) were identified as independent risk factors for increased length of hospital stay. Terlipressin and Octreotide have similar outcomes in terms of control of bleeding, hospital stay, mortality, and side effects when used as adjuvant therapy for the management of variceal bleeding.

New record of Philometra species from the marine edible fish Terapon jarbua collected from the Sindh, Arabian Sea, Pakistan

Diseases in fish due to helminth parasites, especially Philometra species, are the primary worry in aquaculture. Philometra are responsible for health problem in fishes they directly affect fish growth and population parameters. A comprehensive survey was conducted involving the examination of the marine fish species Terapon jarbua, gathered from the coastal waters of Sindh, Pakistan In this research different Philometra species from marine fish Terapon jarbua during 2021 and 2022. Philometra nematodes, belonging to the family Philometridae, are common parasitic organisms inhabiting both marine and freshwater environments. Their prevalence, particularly when existing in high numbers within host organisms, can lead to severe and potentially lethal consequences. Employing light microscopy techniques, diverse species of Philometra were identified, including Philometra teraponi, P. jarbuai, P. arabiai, P. karachii, and P. awarii, localized primarily within the ovaries of the host fish. A total of 140 fish samples were examined and 76 were infected. The intensity of infected fish was 54.28%. The identification process encompassed meticulous analysis of crucial parameters, such as body size, esophagus length, positioning of the nerve ring, dimensions of the ventriculus, and ligament size. Intriguingly, the parasites were found in varying contexts; while some were free within the ovaries, others were embedded within tissues, inducing severe muscular dystrophy. This research presents novel findings of Philometra nematodes in the marine waters of Pakistan, extending their host and geographical distribution records. Future studies are needed to better evaluate and describe the dynamics and the epidemiology of Philometra infection in wild and cultured fish species.

Identification of a novel variant in GPR56/ADGRG1 gene through whole exome sequencing in a consanguineous Pakistani family

GPR56 gene is best known for its pivotal role in cerebral cortical development. Mutations inGPR56give rise to cobblestone-like brain malformation, white matter changes and cerebellar dysplasia. This study aimed to identify causative variant in a consanguineous family having five individuals affected with developmental delay, mild to severe intellectual disability, speech impairment, strabismus and seizures. Whole exome sequencing was performed to identify mutation in affected individuals. Variants were filtered and further validated by Sanger sequencing and segregation analysis. A novel frameshift variant c.1601dupT leading to p.Ala535GlyfsTer17) was identified in GPR56 gene by whole exome sequencing and subsequent filtering. All five affected individuals were homozygous for the mutant allele while four asymptomatic individuals carried the variant in heterozygous state. Radiological findings of a representative patient presented features of GPR56-associated cobblestone like brain malformation. MRI findings suggested paucity of sulci, dilated ventricular system and brainstem atrophy. The microgyria were observed in a simplified gyral pattern (cobblestone). This single bp insertion, and the consequent frameshift, results in the truncation of GPR56 protein. This could result in a malformed cortex giving the brain a cobblestone like shape. Our study identified a 7^th novel frameshift variant from Pakistani population in GPR56 gene, thus broadening mutation spectrum.

1123 An Audit of Pick-Up Rate of Random Colonic Biopsies

Aim

We aimed to evaluate optimal random biopsy criteria are being followed in our institution to increase the diagnostic yield of a subsequent histopathological examination and to reduce the number of unnecessary biopsies in which histopathology is unlikely to deliver clinically useful information and causing a burden on health resources in terms of cost and manpower.

Method

Our study was a retrospective on 419 random colonoscopy biopsies performed over 6 months. Data collection included variables such as age, gender, indications, request of urgency, and histology findings. Data analysis was done descriptively.

Results

Out of 419 random biopsies, only 10.02% had positive findings. The total number of histology results with microscopic colitis was 10. The main indication of the random colonic biopsy was a change in bowel habits (328 cases) followed by significant diarrhea greater than 50 years in 20 cases. In patients with a change in bowel habits, 2.44% of histopathology specimens revealed microscopic colitis. The percentage of random colonic biopsy histology in patients greater than 50 years with significant diarrhea showed microscopic colitis was 10%.

Conclusions

Our study revealed random biopsy during colonoscopy should only be done in selected patients otherwise it has low diagnostic yields biopsy and should only be reserved for patients with risk factors for optimum utilization of health resources and to reduce the cost burden. A scoring system may be helpful to risk-stratify patients in low and high risk for MC to determine which patients qualify for RCB.

Homozygous GRID2 missense mutation predicts a shift in the D-serine binding domain of GluD2 in a case with generalized brain atrophy and unusual clinical features

Background

Spinocerebellar ataxias comprise a large and heterogeneous group of disorders that may present with isolated ataxia, or ataxia in combination with other neurologic or non-neurologic symptoms. Monoallelic or biallelic GRID2 mutations were recently reported in rare cases with cerebellar syndrome and variable degree of ataxia, ocular symptoms, hypotonia and developmental delay.

Case presentation

We report on a consanguineous family with autosomal recessive childhood onset of slowly progressive cerebellar ataxia and delayed psychomotor development in three siblings. MRI of an adult and affected family member revealed slightly widened cerebral and cerebellar sulci, suggesting generalized brain atrophy, and mild cerebellar atrophy. Using whole exome sequencing we identified a novel homozygous missense variant [c.2128C > T, p.(Arg710Trp)] in GRID2 that segregates with the disease. The missense variant is located in a conserved region encoding the extracellular serine-binding domain of the GluD2 protein and predicts a change in conformation of the protein.

Conclusion

The widespread supratentorial brain abnormalities, absence of oculomotor symptoms, increased peripheral muscle tone and the novel missense mutation add to the clinical and genetic variability in GRID2 associated cerebellar syndrome. The neuroradiological findings in our family indicate a generalized neurodegenerative process to be taken into account in other families segregating complex clinical features and GRID2 mutations.

Treatment of advanced chemo-refractory epithelial ovarian cancer with aromatase inhibitor

e16561

Background: In advanced epithelial ovarian cancer non-steroidal antiestrogens yields clinical responses in a significant number of patients. This raises the possibility of therapeutic effectiveness of aromatase inhibitors in epithelial ovarian cancer in post menopausal women. Therefore this study was carried out to document the effectiveness of an aromatase inhibitor, in advanced epithelial ovarian cancer patients with unknown hormone receptor status. Methods: From January 2006 to April 2007, a total of 38 patients were enrolled. Patients with histopathologically confirmed advanced epithelial ovarian cancer were included. Other eligibility requirements were: postmenopausal women, failure of third-line chemotherapy, age between 50–70 years, bidimensionally measurable disease, and CA-125 of more than 100 u/mL. An adequate hematologic, hepatic, and renal profile, and ECOG performance of 0–2 was required. Tablet letrozole 2.5 mg orally once daily was given for 03 months. CA-125 and Miller criteria were used for response evaluation. Results: No patient showed the evidence of complete or partial clinical response. Four patients had stable disease for 8 weeks. All patients showed progressive disease on week 12. Conclusions: In this small series no evidence of effectiveness of aromatase inhibitor letrozole in chemo refractory epithelial ovarian cancer is documented in patients with unknown hormone receptor status. It is, therefore, recommended that further study should only be carried out in the selected patient population with documented positive ER/PR hormone receptors.

No significant financial relationships to disclose.