Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 28
Filter
Add more filters

Country/Region as subject
Publication year range
1.
Hum Genet ; 140(8): 1143-1156, 2021 Aug.
Article in English | MEDLINE | ID: mdl-33974130

ABSTRACT

Biallelic STX3 variants were previously reported in five individuals with the severe congenital enteropathy, microvillus inclusion disease (MVID). Here, we provide a significant extension of the phenotypic spectrum caused by STX3 variants. We report ten individuals of diverse geographic origin with biallelic STX3 loss-of-function variants, identified through exome sequencing, single-nucleotide polymorphism array-based homozygosity mapping, and international collaboration. The evaluated individuals all presented with MVID. Eight individuals also displayed early-onset severe retinal dystrophy, i.e., syndromic-intestinal and retinal-disease. These individuals harbored STX3 variants that affected both the retinal and intestinal STX3 transcripts, whereas STX3 variants affected only the intestinal transcript in individuals with solitary MVID. That STX3 is essential for retinal photoreceptor survival was confirmed by the creation of a rod photoreceptor-specific STX3 knockout mouse model which revealed a time-dependent reduction in the number of rod photoreceptors, thinning of the outer nuclear layer, and the eventual loss of both rod and cone photoreceptors. Together, our results provide a link between STX3 loss-of-function variants and a human retinal dystrophy. Depending on the genomic site of a human loss-of-function STX3 variant, it can cause MVID, the novel intestinal-retinal syndrome reported here or, hypothetically, an isolated retinal dystrophy.


Subject(s)
Eye Diseases, Hereditary/genetics , Intestinal Mucosa/metabolism , Malabsorption Syndromes/genetics , Microvilli/pathology , Mucolipidoses/genetics , Polymorphism, Single Nucleotide , Qa-SNARE Proteins/genetics , Retinal Cone Photoreceptor Cells/metabolism , Retinal Dystrophies/genetics , Aged , Aged, 80 and over , Alcohol Oxidoreductases/genetics , Alcohol Oxidoreductases/metabolism , Animals , Autopsy , Co-Repressor Proteins/genetics , Co-Repressor Proteins/metabolism , Eye Diseases, Hereditary/metabolism , Eye Diseases, Hereditary/pathology , Female , Gene Expression Regulation , Homozygote , Humans , Intestinal Mucosa/pathology , Malabsorption Syndromes/metabolism , Malabsorption Syndromes/pathology , Mice , Mice, Knockout , Microvilli/genetics , Microvilli/metabolism , Mucolipidoses/metabolism , Mucolipidoses/pathology , Phenotype , Qa-SNARE Proteins/deficiency , RNA, Messenger/genetics , RNA, Messenger/metabolism , Retinal Cone Photoreceptor Cells/pathology , Retinal Dystrophies/metabolism , Retinal Dystrophies/pathology , Sensory Rhodopsins/genetics , Sensory Rhodopsins/metabolism , Exome Sequencing
2.
Helicobacter ; 19(4): 306-11, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24799138

ABSTRACT

BACKGROUND: Helicobacter pylori (H. pylori) infection is the most common chronic bacterial infection in humans. Its prevalence in Omani adults and children is not known. OBJECTIVE: To report histology-based H. pylori infection prevalence in Omani children. METHODS: A retrospective study of biopsy proven H. pylori infection in children over a 3 year period in a single center. Age, gender, indication for endoscopy, history of recurrent abdominal pain, and anemia were compared between H. pylori-positive and negative children. RESULTS: Of 143 patients who underwent endoscopy, gastric biopsies were available on 112. The overall prevalence of biopsy proven H. pylori infection was 25%. The prevalence in children with recurrent abdominal pain was 30% compared to 22% in children who underwent endoscopy for other indications (p = .382). The prevalence increased from 7% in children aged <5 years, to 33% in those aged between 5 and 10 years (p = .010). There was no significant difference in the prevalence between the 5-10 years age group (33%) and older age group (29%) (p = .814). There was no significant difference in gender or anemia between the two groups. CONCLUSIONS: This study represents the first reported study on the prevalence of biopsy proven H. pylori infection in Omani children. H. pylori infection prevalence is 25%, is lower than regional and many Arab countries. The prevalence appears to increase till age of 5 years. There was no significant association between H. pylori and recurrent abdominal pain, gender, or anemia.


Subject(s)
Helicobacter Infections/epidemiology , Helicobacter pylori/isolation & purification , Adolescent , Biopsy , Child , Child, Preschool , Female , Humans , Infant , Male , Oman/epidemiology , Prevalence , Retrospective Studies , Stomach/microbiology , Stomach/pathology
3.
Vaccines (Basel) ; 12(1)2024 Jan 20.
Article in English | MEDLINE | ID: mdl-38276676

ABSTRACT

Vaccination provides the best protection against the increasing infections of SARS-CoV-2. The magnitude and type of anti-SARS-CoV-2 vaccine side effects (SEs) depend on parameters that are not fully understood. In this cross-sectional study, the associations between different anti-SARS-CoV-2 vaccine SEs and age, sex, the presence of chronic diseases, medication intake, history of allergies, and infections with SARS-CoV-2 were investigated. Our survey used the Google platform and had 866 participants, contacted through e-mails, social media and chain referral sampling (margin of error ≈ 4.38%, 99% confidence). More than 99% of the participants received the BNT162b2 and ChAdOx1-S vaccines. Being female, having chronic diseases, taking medicines routinely and the presence of a SARS-CoV-2 infection (p < 0.05) were associated with strong SEs after the BNT162b2 vaccine second dose. Having a history of allergies and a female sex (p < 0.01) were associated with strong SEs after the ChAdOx1-S vaccine second dose. Furthermore, the results reveal, for the first time, the associations between having a history of allergies, chronic diseases, medication usage, and SEs of a strong magnitude for the BNT162b2 and ChAdOx1-S vaccines. Additionally, this study supports the association of the female sex and infection with SARS-CoV-2 with an increased potential of developing stronger SEs with certain anti-SARS-CoV-2 vaccines.

5.
Oman Med J ; 37(3): e384, 2022 May.
Article in English | MEDLINE | ID: mdl-35814040

ABSTRACT

Objectives: An estimated 887 000 deaths were due to chronic hepatitis B (CHB) related complications in 2015 worldwide. Most of these deaths were related to decompensated liver cirrhosis and hepatocellular carcinoma (HCC). Oman is a country with an intermediate prevalence of CHB. The Hepatitis B vaccine was introduced in Oman in 1990, with a vaccine coverage rate of > 95% reported in 2005. Despite the association between CHB and liver cirrhosis and HCC, no available data from Oman demonstrates CHB-related liver cirrhosis. We sought to estimate the prevalence of CHB among patients with liver cirrhosis from Oman. Methods: We conducted a retrospective chart review of patients diagnosed with liver cirrhosis at Sultan Qaboos University Hospital and Armed Forces Hospital between January 2006 and April 2013. All pediatric and adult patients with liver cirrhosis were included. We collected demographic data and liver cirrhosis investigations. Results: A total of 419 patients were included. Two-thirds of the patients were males. The median age was 59 years. Omani patients represented the majority (97.1%) of patients with cirrhosis. Diabetes mellitus was present in almost half of the patients, and 22.2% indicated alcohol consumption. Evidence of previous or current hepatitis B virus (HBV) infection was found in about half of the cohort (51.3%). Only 3.3% of CHB patients were positive for hepatitis B e-Antigen. HBV DNA was detected in 47 patients (21.9%), of which 20 patients had a high viral load > 2000 IU/ml. More than a third (36.7%) had positive hepatitis B surface antibody (anti-HBs), indicating immunity to HBV, and 27.1% was due to previous HBV infection, 5.2% was immune due to vaccination, and 3.7% had positive anti-HBs and unknown anti-HBc status. Negative anti-HBs was found in 34.1% of the cohort and 29.9% had unknown immunity status. HBV coinfection with HCV was found in 24.7% of HBV patients with cirrhosis. Conclusions: Serological markers of CHB are common among liver cirrhosis patients in Oman. CHB related cirrhosis was more common in old age males than females (70.7% vs. 29.3%, respectively; p < 0.010). Evidence of past or present HBV infection was found in > 50% of the patients.

6.
Sultan Qaboos Univ Med J ; 20(3): e316-e322, 2020 Aug.
Article in English | MEDLINE | ID: mdl-33110647

ABSTRACT

OBJECTIVES: Hepatocellular carcinoma (HCC) is the most common type of primary liver tumour worldwide and is increasing in incidence. This study aimed to describe the clinical characteristics of HCC among Omani patients, along with its major risk factors, outcomes and the role of surveillance. METHODS: This retrospective case-series study was conducted between January 2008 and December 2015 at the three main tertiary care hospitals in Oman. All adult Omani patients diagnosed with HCC and visited these hospitals during the study period were included. Relevant data were collected from the patients' electronic medical records. RESULTS: A total of 284 HCC patients were included in the analysis. The mean age was 61.02 ± 11.41 years and 67.6% were male. The majority had liver cirrhosis (79.9%), with the most common aetiologies being chronic hepatitis C (46.5%) and B (43.2%). Only 13.7% of cases were detected by the HCC surveillance programme. Approximately half of the patients (48.5%) had a single liver lesion and 31.9% had a liver tumour of >5 cm in size. Approximately half (49.2%) had alpha-fetoprotein levels of ≥200 ng/mL. The majority (72.5%) were diagnosed using multiphase computed tomography alone. Less than half of the patients (48.9%) were offered one or more HCC treatment modalities. CONCLUSION: The majority of Omani HCC patients were male and had cirrhosis due to viral hepatitis. In addition, few patients were identified by the national surveillance programme and presented with advanced disease precluding therapeutic or even palliative treatment.


Subject(s)
Carcinoma, Hepatocellular/classification , Adult , Aged , Aged, 80 and over , Carcinoma, Hepatocellular/epidemiology , Case-Control Studies , Female , Humans , Incidence , Liver Cirrhosis/diagnosis , Liver Cirrhosis/epidemiology , Liver Neoplasms/classification , Liver Neoplasms/diagnosis , Liver Neoplasms/epidemiology , Male , Middle Aged , Oman/epidemiology , Retrospective Studies , Risk Factors
7.
Pediatr Transplant ; 13(2): 160-70, 2009 Mar.
Article in English | MEDLINE | ID: mdl-19037913

ABSTRACT

The theoretical risks of early SW, <3 months post-LT, and complete elimination (steroid-free LT) lie in mainly three areas, namely the risks of AGR, CGR, and the development of d-AIH that has been described in SW post-LT in children. These should be balanced against the benefits of early SW mainly manifested as effects on growth post-LT. In this paper, we focused on the clinical trials that included CS therapy risks and benefits in pediatric LT. Focusing mainly on CGR and d-AIH as risks, and the beneficial effects on growth post-LT with either low-dose CS, SW, or steroid-free regimens. Main conclusions from comparing a large number of studies are: early SW or elimination from immunosuppression protocols was neither harmful to the patient nor to the graft survival rate in the short term, the overall impression is that steroids negatively affect growth in LT recipients when used in high doses and prolonged course, and that development of d-AIH is not associated with CS therapy with evidence that chronic low dose steroids post-LT have no preventative role against d-AIH.


Subject(s)
Adrenal Cortex Hormones/therapeutic use , Immunosuppressive Agents/pharmacology , Liver Transplantation/methods , Child , Graft Rejection , Graft Survival , Growth/immunology , Growth Disorders/etiology , Growth Disorders/immunology , Hepatitis, Autoimmune , Humans , Liver Transplantation/adverse effects , Lymphoproliferative Disorders/etiology , Steroids/therapeutic use , Time Factors , Treatment Outcome
8.
Oman Med J ; 34(6): 482-489, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31745411

ABSTRACT

Cystic fibrosis (CF) is a multisystem disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. CFTR is expressed in the apical surface of cholangiocytes. Homozygous CFTR gene mutation results in viscous and acidic bile secretions secondary to deficient surface fluid and bicarbonate efflux. Viscous, inspissated bile causes ductular obstruction and hepatotoxicity from retained bile components, leading to fibrosis and ultimately cirrhosis, known as CF liver disease (CFLD). CFLD is the third leading cause of death in CF patients. CFLD manifestations can take many forms. They range from asymptomatic elevation of transaminases to cirrhosis and end-stage liver disease. CFLD is diagnosed after excluding other causes of chronic liver disease. To date, there is no effective therapy to prevent or treat CFLD. Management of CFLD emphasizes on optimizing nutritional status. Ursodeoxycholic acid is the only available treatment that may prevent progression of CFLD at present. All CF patients with CFLD need annual investigations and follow-up for early detection of the disease. Liver transplantation should be considered in patients with decompensated cirrhosis and portal hypertension, with acceptable long-term outcomes. Novel therapies of CFLD are promising. This review article aims to summarize the published literature on CFLD, its pathophysiology, clinical features and complications, and management including new therapeutic options.

9.
J Grad Med Educ ; 11(4 Suppl): 104-109, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31428266

ABSTRACT

BACKGROUND: Research during residency is associated with better clinical performance, improved critical thinking, and increased interest in an academic career. OBJECTIVE: We examined the rate, characteristics, and factors associated with research publications by residents in Oman Medical Specialty Board (OMSB) programs. METHODS: We included residents enrolled in 18 OMSB residency programs between 2011 and 2016. Resident characteristics were obtained from the OMSB Training Affairs Department. In April 2018, MEDLINE and Google Scholar databases were searched independently by 2 authors for resident publications in peer-reviewed journals using standardized criteria. RESULTS: Over the study period, 552 residents trained in OMSB programs; 64% (351 of 552) were female, and the mean age at matriculation was 29.4 ± 2.2 years. Most residents (71%, 393 of 552) were in the early stages of specialty training (R ≤ 3) and 49% (268 of 552) completed a designated research block as part of their training. Between 2011 and 2016, 43 residents published 42 research articles (range, 1-5 resident authors per article), for an overall publication rate of 8%. Residents were the first authors in 20 (48%) publications. Male residents (odds ratio [OR] = 2.07; P = .025, 95% CI 1.1-3.91) and residents who completed a research block (OR = 2.57; P = .017, 95% CI 1.19-5.57) were significantly more likely to publish. CONCLUSIONS: Research training during residency can result in tangible research output. Future studies should explore barriers to publication for resident research and identify interventions to promote formal scholarly activity during residency.


Subject(s)
Biomedical Research , Internship and Residency , Publications/trends , Adult , Bibliometrics , Education, Medical, Graduate , Female , Humans , Male , Oman , Specialty Boards
11.
Oman Med J ; 36(3): e260, 2021 May.
Article in English | MEDLINE | ID: mdl-34026280
14.
Oman Med J ; 30(2): 138-41, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25960841

ABSTRACT

Wolcott-Rallison syndrome (WRS) is an autosomal recessive disease, characterized by neonatal or early-onset non-autoimmune insulin-dependent diabetes. WRS, although rare, is recognized to be the most frequent cause of neonatal-onset diabetes. The majority of reported patients are from consanguineous families. Several mutations with variable expression of the syndrome are reported. Here we describe a six-year-old boy with WRS who was evaluated at Sultan Qaboos University Hospital and was found to have a novel homozygous nonsense mutation in the EIF2AK3 gene. His younger sister also had WRS but with milder expression. The mutation exhibited different clinical characteristics in the siblings proving that WRS patients phenotypic variability correlates poorly to genotype. This is the first case report of two Omani children with WRS and a report of a novel mutation.

15.
Sultan Qaboos Univ Med J ; 15(1): e46-51, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25685385

ABSTRACT

OBJECTIVES: Regular blood transfusions are essential for patients with thalassaemia major. However, infections with hepatotropic viruses remain a major concern. The objective of this study was to evaluate the prevalence and characteristics of hepatitis C viral (HCV) infection among patients with homozygous beta thalassaemia in a single centre in Oman. METHODS: A retrospective chart review of 200 patients treated at the Thalassemia Unit of Sultan Qaboos University Hospital (SQUH) in Muscat, Oman, between August 1991 and December 2011 was performed. Relevant demographic and clinical characteristics were collected, including age, gender, HCV status and the presence of endocrinopathies. RESULTS: A total of 81 patients (41%) were found to be anti-HCV-antibody (anti-HCV)-positive. HCV ribonucleic acid tests were performed on 65 anti-HCV-positive patients and were positive among 33 (51%); the remaining 16 patients died before these tests were available. Anti-HCV-positive patients were significantly older than anti-HCV-negative patients (P <0.001) and were more likely to be diabetic than anti-HCV-negative patients (27% versus 8%; P <0.001). A total of 100 patients had been transfused before they were transferred to SQUH in 1991; of these, 70 (70%) were anti-HCV-positive. Only 11 (11.5%) of the 96 patients who were seronegative in 1991, or who were transfused later, became seropositive. CONCLUSION: It is likely that the high prevalence of HCV among multi-transfused thalassaemic patients in Oman is due to blood transfusions dating from before the implementation of HCV screening in 1991 as the risk of HCV-associated transfusions has significantly reduced since then. Additionally, results showed that anti-HCV-positive patients were more likely to be diabetic than anti-HCV-negative patients.

16.
Sultan Qaboos Univ Med J ; 15(2): e234-40, 2015 May.
Article in English | MEDLINE | ID: mdl-26052457

ABSTRACT

OBJECTIVES: Parenteral nutrition-associated cholestasis (PNAC) is one of the most challenging complications of prolonged parenteral nutrition (PN) in neonates. There is a lack of research investigating its incidence in newborn infants in Oman and the Arab region. Therefore, this study aimed to assess the incidence of PNAC and its risk factors in Omani neonates. METHODS: This retrospective study took place between January and April 2014. All neonates who received PN for ≥14 days during a four-year period (June 2009 to May 2013) at the neonatal intensive care unit (NICU) in Sultan Qaboos University Hospital, Muscat, Oman, were enrolled. RESULTS: A total of 1,857 neonates were admitted to the NICU over the study period and 135 neonates (7.3%) received PN for ≥14 days. Determining the incidence of PNAC was only possible in 97 neonates; of these, 38 (39%) had PNAC. The main risk factors associated with PNAC were duration of PN, duration of enteral starvation, gastrointestinal surgeries, blood transfusions and sepsis. Neonates with PNAC had a slightly higher incidence of necrotising enterocolitis in comparison to those without PNAC. CONCLUSION: This study found a PNAC incidence of 39% in Omani neonates. There were several significant risk factors for PNAC in Omani neonates; however, after logistic regression analysis, only total PN duration remained statistically significant. Preventive strategies should be implemented in NICUs so as to avoid future chronic liver disease in this population.

17.
Horm Res Paediatr ; 83(3): 190-7, 2015.
Article in English | MEDLINE | ID: mdl-25659842

ABSTRACT

BACKGROUND: Wolcott-Rallison syndrome (WRS) is caused by recessive EIF2AK3 mutations and characterized by early-onset diabetes and skeletal dysplasia. Hepatic dysfunction has been reported in 60% of patients. AIMS: To describe a cohort of WRS patients and discuss the pattern and management of their liver disease. METHODS: Detailed phenotyping and direct sequencing of EIF2AK3 gene were conducted in all patients. RESULTS: Twenty-eight genetically confirmed patients (67% male; mean age 4.6 years) were identified. 17 different EIF2AK3 mutations were detected, of which 2 were novel. The p.S991N mutation was associated with prolonged survival and p.I650T with delayed onset. All patients presented before 25 months with diabetes with variation in the frequency and severity of 10 other features. Liver disease, first manifested as non-autoimmune hepatitis, was the commonest extra-pancreatic feature identified in 85.7% (24/28). 22/24 had at least one episode of acute hepatic failure which was the cause of death in all deceased patients (13/28). One child was treated by liver transplantation and had no liver disease and better diabetes control for the following 6 years. CONCLUSIONS: Liver disease in WRS is more frequent than previously described and carries high mortality. The first experience with liver transplantation in WRS is encouraging.


Subject(s)
Diabetes Mellitus, Type 1 , Epiphyses/abnormalities , Hepatitis , Liver Failure , Liver Transplantation , Osteochondrodysplasias , eIF-2 Kinase/genetics , Child, Preschool , Cohort Studies , Comorbidity , Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 1/mortality , Diabetes Mellitus, Type 1/surgery , Epiphyses/surgery , Female , Hepatitis/genetics , Hepatitis/mortality , Hepatitis/surgery , Humans , Liver Failure/genetics , Liver Failure/mortality , Liver Failure/surgery , Male , Mutation , Osteochondrodysplasias/genetics , Osteochondrodysplasias/mortality , Osteochondrodysplasias/surgery
19.
Oman Med J ; 28(1): 53-5, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23386947

ABSTRACT

Infantile Systemic Hyalinosis (ISH) (OMIM 236490) is a rare, progressive and fatal autosomal recessive disorder characterized by multiple subcutaneous skin nodules, gingival hypertrophy, osteopenia, joint contractures, failure to thrive, diarrhea with protein losing enteropathy, and frequent infections. There is diffuse deposition of hyaline material in the skin, gastrointestinal tract, muscle and endocrine glands. It is caused by mutations in the ANTXR2 (also known as CMG2) gene, which encodes a trans-membranous protein involved in endothelial development and basement membrane-extracellular matrix assembly. We describe a child with classical features of ISH presenting in infancy with severe chronic debilitating pain and progressive joint contractures. The diagnosis was confirmed by molecular DNA sequencing of ANTXR2 gene which revealed a novel homozygous mutation not previously reported; 79 bp deletion of the entire exon 11 (c.867_945del, p.E289DfsX22). Although this is the first reported case of ISH in Oman, we believe that the disease is under-diagnosed since children affected with this lethal disease pass away early in infancy prior to establishing a final diagnosis.

20.
Can J Gastroenterol ; 27(1): e8-12, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23378985

ABSTRACT

Chronic hepatitis C infection is a major global health problem. The WHO estimates the number of infected people worldwide to be approximately 170 million. The estimated number of hepatitis C virus (HCV)-infected people in Canada is approximately 250,000, with approximately 5000 Canadians newly infected each year. Based on the identification of genomic differences, HCV has been classified into six genotypes; genotype may influence the outcome of antiviral therapy. HCV genotypes 1, 2 and 3 are widely distributed throughout the world and have been the focus of the majority of epidemiological, natural course and treatment studies. Although HCV genotypes 5 and 6 are prevalent in certain geographical areas, they are studied less extensively. HCV genotypes 5 and 6 are uncommon in Canada and account for less than 5% of HCV-infected Canadians. However, immigration and travel can alter the epidemiology of these uncommon genotypes. The present article reviews and summarizes the available data regarding the epidemiology and treatment of HCV genotypes 5 and 6. Genotype 5 is endemic in the northern part of South Africa while genotype 6 is reported primarily in Asia. Available data show that 48 weeks of treatment with a combination of pegylated interferon and ribavirin lead to a higher sustained virological response compared with HCV genotypes 1 and 4. None of the approved direct-acting antiviral agents is currently recommended for the treatment of HCV genotypes 5 or 6.


Subject(s)
Antiviral Agents/therapeutic use , Hepacivirus/isolation & purification , Hepatitis C, Chronic/drug therapy , Canada/epidemiology , Genotype , Global Health , Hepacivirus/genetics , Hepatitis C, Chronic/epidemiology , Hepatitis C, Chronic/virology , Humans , Treatment Outcome
SELECTION OF CITATIONS
SEARCH DETAIL