5 research outputs found
A nonsense mutation in S-antigen (p.Glu306*) causes Oguchi disease
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110974.pdf (publisher's version ) (Open Access)PURPOSE: Genetic studies were performed to identify the causative mutation in a 15-year-old girl diagnosed with congenital stationary night blindness (CSNB) presenting Mizuo-Nakamura phenomenon, a typical Oguchi disease symptom. The patient also had dural sinus thrombosis (DST), thrombocytopenia, and systemic lupus erythematosus (SLE). METHODS: Mutation analysis was done by sequencing two candidate genes, S-antigen (SAG; arrestin 1), associated with Oguchi type 1, and rhodopsin kinase (GRK1), associated with Oguchi type 2. In addition, the C677T variation in the methylenetetrahydrofolate reductase (MTHFR) gene was also screened in the family, to determine its probable association with hyperhomocysteinemia in the patient. RESULTS: Sequencing of the SAG and GRK1 resulted in identifying a novel homozygous nonsense mutation (c.916G>T; p.Glu306*) in SAG, which in unaffected siblings either was present in a heterozygous state or absent. The C677T heterozygous allele in the MTHFR gene was found to be associated with hyperhomocysteinemia in the patient and other family members. CONCLUSIONS: This is the first report of Oguchi type 1 in a Pakistani patient due to a nonsense mutation (c.916G>T; p.Glu306*) in SAG. The neurologic and hematological abnormalities likely are not associated with the SAG variant
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Serial Magnetic Resonance Imaging in Creutzfeldt-Jakob Disease: a Case Report and Literature Review
Creutzfeldt-Jakob disease (CJD) is a rare, degenerative, invariably fatal brain disorder. CJD usually appears in later life and runs a rapid course. Typically, the onset of symptoms occurs about age 60 and about 90% of individuals die within one year. We report a case of 67-year-old male presented with progressive aphasia, confusion, dysphagia and inability to carry out activities of daily life (ADLs) over a period of three to four weeks. The patient had past medical history of chronic atrial fibrillation and hypertension. Prior to admission, the patient was treated for ischemic stroke of left basal ganglia but continued to have worsening encephalopathy. The spinal tap revealed a 14-3-3 protein level of thirteen times the upper limit of normal; electroencephalogram (EEG) showed a diffuse slowing of the background and periodic sharp waves with greater involvement of the left hemisphere. Diffusion-weighted imaging (DWI) magnetic resonance imaging (MRI) at the time of admission showed extensive signal abnormality in the basal ganglia bilaterally and in the cerebral cortex bilaterally, particularly over the left cerebral hemisphere. The persistence of the MRI findings over several weeks was concerning for spongiform encephalopathy. The probable diagnosis of Creutzfeldt-Jakob disease was made based on these imaging findings taken together with the patient’s clinical signs and symptoms of a rapidly progressive encephalopathy. The patient was able to have some quality time with his family as the diagnosis was made earlier than perhaps otherwise and expired peacefully after comfort care measures were chosen. Serial MRI may serve as a clue to the early diagnosis of CJD and potentially provide a better quality of life for the patients