title: Retinitis pigmentosa and bilateral cystoid macular oedema in a patient heterozygous for the RIM1 mutation previously associated with cone-rod dystrophy 7.
abstract: Autosomal dominant cone-rod dystrophy 7 (CORD7) has been previously associated with the RIM1 c.2459G>A (Arg820His) mutation. Cystoid macular oedema (CMO) is a rare feature of CORD and has not been described in CORD7. We report a patient who was heterozygous for the RIM1 mutation with bilateral CMO and who manifested a retinitis pigmentosa phenotype.
  
  
  
  The patient's medical notes were retrospectively reviewed over an 18-month period. Genetic testing was performed by next generation sequencing for a panel of 176 genes associated with retinal dystrophy.
  
  
  
  A 34-year-old man presented with a 5-year history of bilateral floaters and blurred vision. Visual acuity was 20/23 and 20/33 in the right and left eyes, respectively. Optical coherence tomography scans revealed bilateral CMO. Goldmann visual field tests detected mid-peripheral ring scotomas. Electrodiagnostic testing was overall consistent with a primary photoreceptor abnormality involving both rods and cones. Subsequent genetic testing identified heterozygosity for the RIM1 c.2459G>A (Arg820His) mutation. Various treatments for CMO were trialled unsuccessfully. However, at his latest clinic appointment the CMO had partially improved following topical brinzolamide therapy. Most recent visual acuity was 20/25 in the right eye and 20/24 in the left eye.
  
  
  
  This is the first reported case of bilateral CMO in association with the RIM1 mutation. Overall, our findings were more consistent with a phenotype of retinitis pigmentosa. This could imply that the RIM1 mutation causes diverse retinal dystrophies, or that the previously described CORD7 phenotype resulted from a different variant on the same haplotype.
authors.affiliation: a Clinical Neurosciences Research Group, Clinical and Experimental Sciences, Faculty of Medicine , University of Southampton , Southampton , UK.|b Eye Unit, University Hospital Southampton NHS Foundation Trust , Southampton , UK.
authors.forename: Alasdair N
authors.initials: AN
authors.lastname: Warwick
authors.affiliation: b Eye Unit, University Hospital Southampton NHS Foundation Trust , Southampton , UK.
authors.forename: Fatima
authors.initials: F
authors.lastname: Shawkat
authors.affiliation: a Clinical Neurosciences Research Group, Clinical and Experimental Sciences, Faculty of Medicine , University of Southampton , Southampton , UK.|b Eye Unit, University Hospital Southampton NHS Foundation Trust , Southampton , UK.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Lotery
mesh_terms: D000328:Adult; D002257:Carbonic Anhydrase Inhibitors / Q000627:therapeutic use; D000071700:Cone-Rod Dystrophies / Q000235:genetics*; D004596:Electroretinography; D019204:GTP-Binding Proteins / Q000235:genetics*; D006579:Heterozygote; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D008269:Macular Edema / Q000175:diagnosis / Q000188:drug therapy / Q000235:genetics*; D008297:Male; D009154:Mutation; D012174:Retinitis Pigmentosa / Q000175:diagnosis / Q000235:genetics*; D012189:Retrospective Studies; D013449:Sulfonamides / Q000627:therapeutic use; D013843:Thiazines / Q000627:therapeutic use; D041623:Tomography, Optical Coherence; D014792:Visual Acuity; D058609:Visual Field Tests; D009419:Nerve Tissue Proteins
chemical_list: D002257:Carbonic Anhydrase Inhibitors; D019204:GTP-Binding Proteins; D013449:Sulfonamides; D013843:Thiazines; C111827:brinzolamide; C491492:RIMS1 protein, human; D009419:Nerve Tissue Proteins
keywords: CORD7; Cone-rod dystrophy 7; RAB3A-interacting molecule 1; RIM1; cystoid macular oedema; retinitis pigmentosa