Osama Muthaffar

Dr. Osama Muthaffar

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Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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27 January 2023 in Genes
Verified
Journal Article
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QZQaiser ZAMAN
Qaiser ZAMAN
MKMuhammad Abbas Khan
Muhammad Abbas Khan
KSKalsoom Sahar
Kalsoom Sahar
GRGauhar Rehman
Gauhar Rehman
HKHamza Khan
Hamza Khan
Musharraf JelaniMusharraf Jelani
Musharraf Jelani
Charcot–Marie–Tooth disease (CMT) and autosomal recessive spastic ataxia of Charlevoix–Saguenay type (ARSACS) are large heterogeneous groups of sensory, neurological genetic disorders characterized by sensory neuropathies, muscular atrophies, abnormal sensory conduction velocities, and ataxia. CMT2EE (OMIM: 618400) is caused by mutations in MPV17 (OMIM: 137960), CMT4F (OMIM: 614895) is caused by PRX (OMIM: 605725), CMTX1 (OMIM: 302800) is caused by mutations in GJB1 (OMIM: 304040), and ARSACS (OMIM: 270550) is caused by mutations in SACS (OMIM: 604490). In this study, we enrolled four families: DG-01, BD-06, MR-01, and ICP-RD11, with 16 affected individuals, for clinical and molecular diagnoses. One patient from each family was analyzed for whole exome sequencing and Sanger sequencing was done for the rest of the family members. Affected individuals of families BD-06 and MR-01 show complete CMT phenotypes and family ICP-RD11 shows ARSACS type. Family DG-01 shows complete phenotypes for both CMT and ARSACS types. The affected individuals have walking difficulties, ataxia, distal limb weakness, axonal sensorimotor neuropathies, delayed motor development, pes cavus, and speech articulations with minor variations. The WES analysis in an indexed patient of family DG-01 identified two novel variants: c.83G>T (p.Gly28Val) in MPV17 and c.4934G>C (p.Arg1645Pro) in SACS. In family ICP-RD11, a recurrent mutation that causes ARSACS, c.262C>T (p.Arg88Ter) in SACS, was identified. Another novel variant, c.231C>A (p.Arg77Ter) in PRX, which causes CMT4F, was identified in family BD-06. In family MR-01, a hemizygous missense variant c.61G>C (p.Gly21Arg) in GJB1 was identified in the indexed patient. To the best of our knowledge, there are very few reports on MPV17, SACS, PRX, and GJB1 causing CMT and ARSACS phenotypes in the Pakistani population. Our study cohort suggests that whole exome sequencing can be a useful tool in diagnosing complex multigenic and phenotypically overlapping genetic disorders such as Charcot–Marie–Tooth disease (CMT) and spastic ataxia of Charlevoix–Saguenay type.

5 January 2023 in Genes
Verified
Journal Article
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QZQaiser ZAMAN
Qaiser ZAMAN
SASadeeda
Sadeeda
MAMuhammad Anas
Muhammad Anas
GRGauhar Rehman
Gauhar Rehman
QKQadeem Khan
Qadeem Khan
MNMuhammad Imran Naseer
Muhammad Imran Naseer
Background: Hermansky–Pudlak syndrome (HSP) was first reported in 1959 as oculocutaneous albinism with bleeding abnormalities, and now consists of 11 distinct heterogenic genetic disorders that are caused by mutations in four protein complexes: AP-3, BLOC1, BLOC2, and BLOC3. Most of the patients show albinism and a bleeding diathesis; additional features may present depending on the nature of a defective protein complex. The subtypes 3 and 4 have been known for mutations in HSP3 and HSP4 genes, respectively. Methods: In this study, two Pakhtun consanguineous families, ALB-09 and ALB-10, were enrolled for clinical and molecular diagnoses. Whole-exome sequencing (WES) of the index patient in each family followed by Sanger sequencing of all available samples was performed using 3Billion. Inc South Korea rare disease diagnostics services. Results: The affected individuals of families ALB-09 and ALB-10 showed typical phenotypes of HPS such as oculocutaneous albinism, poor vision, nystagmus, nystagmus-induced involuntary head nodding, bleeding diathesis, and enterocolitis; however, immune system weakness was not recorded. WES analyses of one index patient revealed a novel nonsense variant (NM_032383.4: HSP3; c.2766T > G) in family ALB-09 and a five bp deletion (NM_001349900.2: HSP4; c.1180_1184delGTTCC) variant in family ALB-10. Sanger sequencing confirmed homozygous segregation of the disease alleles in all affected individuals of the respective family. Conclusions: The substitution c.2766T > G creates a premature protein termination at codon 922 in HPS3, replacing tyrosine amino acid with a stop codon (p.Tyr922Ter), while the deletion mutation c.1180_1184delGTTCC leads to a reading frameshift and a premature termination codon adding 23 abnormal amino acids to HSP4 protein (p:Val394Pro395fsTer23). To the best of our knowledge, the two novel variants identified in HPS3 and HPS4 genes causing Hermansky–Pudlak syndrome are the first report from the Pakhtun Pakistani population. Our work expands the pathogenic spectrum of HPS3 and HPS4 genes, provides successful molecular diagnostics, and helps the families in genetic counselling and reducing the disease burden in their future generations.

18 October 2021 in Neurosciences
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Journal Article
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OMOsama Muthaffar
Osama Muthaffar
SASalha M. Almahmudi
Salha M. Almahmudi
MAMuna O. Alrabghi
Muna O. Alrabghi
MMMaria M. Bin Mahfouz
Maria M. Bin Mahfouz
NANuha S. Alfawaz
Nuha S. Alfawaz
Objectives: To evaluate the efficacy of valproic acid (VPA) in a cohort of children below 2 years of age. We also aim to review the characteristics of such patients and the role and safety of VPA for this age group. Methods: A retrospective chart review conducted at King Abdulaziz University Hospital, Jeddah, Kingdome of Saudi Arabia, for children below 2 years of age diagnosed with epilepsy and treated with valproic acid from January 2016 to January 2020. Results: The cohort for this study includes 50 children below the age of 2 years (25 males, 25 females). Aged 3 months to 23 months at commencing valproic acid. The mean age of seizure onset was 9 months and the mean age of starting valproic acid was 16 months. Thirty-two patients (64%) had more than 50% seizure improvement after valproic acid. Eleven patients (22%) were seizure-free. No statistical significance abnormalities in blood count indices and ammonia were seen during the treatment period. Two patients had dose-related lethargy that improved after decreasing their dosage. Asymptomatic mild elevation in glutamate dehydrogenase was noticed in 18% of patients. Conclusion: Using valproic acid in infants and children below the age of 2 years can be considered as a safe and effective treatment option for epilepsy in this age group.

1 November 2020 in Balkan Journal of Medical Genetics
Verified
Journal Article
Open access
OMOsama Muthaffar
Osama Muthaffar
Pediatric neurological disorders have a wide spectrum of clinical presentations and can be challenging to diagnose. Whole exome sequencing (WES) is increasingly becoming an integral diagnostic tool in medicine. It is cost-effective and has high diagnostic yield, especially in consanguineous populations. This study aims to review WES results and its value in diagnosing neurological disorders. A retrospective chart review was performed for WES results between the period of January 2018 to November 2019. Whole exome sequencing was requested for children with unexplained neurological signs and symptoms such as epilepsy, developmental delay, visual impairment, spasticity, hypotonia and magnetic resonance imaging (MRI) brain changes. It was conducted for children in a pediatric neurology clinic of a tertiary center at Jeddah, Saudi Arabia. Twenty-six children with undiagnosed neurological conditions were identified and underwent WES diagnosis. Nineteen patients (73.0%) of the cohort were diagnosed with pathogenic variants, likely pathogenic variants or variants of unknown significance (VUS). Consanguinity was positive in 18 families of the cohort (69.0%). Seven patients showed homozygous mutations. Five patients had heterozygous mutations. There were six patients with VUS and six patients had negative WES results. Whole exome sequencing showed a high diagnostic rate in this group of children with variable neurological disorders.

7 October 2022 in Cureus
Verified
Journal Article
Open access
AAAnas Alyazidi
Anas Alyazidi
OMOsama Muthaffar
Osama Muthaffar
FAFahad A Alotibi
Fahad A Alotibi
AAAlbatool Almubarak
Albatool Almubarak
LTLuca Tamai
Luca Tamai
YAYara K. Alraddadi
Yara K. Alraddadi
The social acceptance of patients with epilepsy is largely determined by society's opinion of epilepsy; therefore, individuals with epilepsy could face prejudice and stigma as a result of negative impressions. Religious beliefs and mystical notions have been shown to influence attitudes toward epilepsy. Health fatalism could also be detrimental to society's and caregivers' approach toward such patients. In extreme settings, this could hinder them from obtaining an adequate treatment process. A cross-sectional exploratory study was conducted from February 2022 to May 2022 in Saudi Arabia, Spain, Scotland, and Italy using an online questionnaire consisting of 33 questions concerning the Health Fatalism Scale (HFS), the Epilepsy Knowledge Scale (EKS), and the Epilepsy Attitude Scale (EAS). A total of 735 health science students (HSS) participated in the present study. The majority of participants were females (64.1%) while male participants represented 34.6% of the study. Health science students currently studying in Saudi Arabia represented the majority of participants with a percentage of 58.5%. Among the four countries, students in Saudi Arabia presented with the highest knowledge mean score. Students in Spain had the highest mean attitude score. Muslim students had the highest mean fatalism scores followed by Christian students. In general, a high level of knowledge was observed among the participants, most notably, among Saudis who presented with the highest level of knowledge across the four countries. Regarding attitude, Spanish students presented the best attitude towards patients with epilepsy. Low fatalism scores were commonly observed across all countries regardless of their different demographic characteristics. Fatalism perception should be further detailed to ensure optimal services are delivered without prejudgment by future healthcare workers.

23 February 2024 in Seizure: European Journal of Epilepsy
Verified
Journal Article
Open access
FBFahad A. Bashiri
Fahad A. Bashiri
KHKhalid Hundallah
Khalid Hundallah
RARaidah Al-Baradie
Raidah Al-Baradie
AAAli Al-Otaibi
Ali Al-Otaibi
OIOmar Ismayl
Omar Ismayl
AAAbdullah Aldakhil
Abdullah Aldakhil
Despite the availability of international recommendations for the management of Infantile Epileptic Spasms Syndrome (IESS), there is a lack of recommendations adapted to the local context of clinical practice of pediatric neurology in the Gulf Cooperation Council (GCC) countries. By an initiative from the Saudi Pediatric Neurology Society (SPNS), a literature review was performed and an expert panel comprised of 13 pediatric neurologists from all GCC countries (Saudi Arabia, Kuwait, Bahrain, Oman, Qatar, and the United Arab Emirates) was subsequently convened to discuss all issues related to the management and diagnosis practices of IESS in the GCC. The overall aim of this consensus document was to develop practical recommendations to support the care of patients with IESS in the GCC and to reflect on how clinical management approaches compare with those adopted internationally.