title: Clinical polymorphism of stargardt disease in a large consanguineous tunisian family; implications for nosology.
abstract: OBJECTIVE
  To describe the polymorphic expression of Stargardt disease in a large Tunisian family with clinical intra- and interfamilial variation of the condition.
  
  
  METHODS
  Twelve subjects from two related families with autosomal recessive Stargardt disease were enrolled. A detailed clinical examination including visual acuity and visual field measurement, fundus photography, fluorescein angiography, electroretinography (ERG) and color vision testing was performed for all subjects.
  
  
  RESULTS
  The youngest child from family A manifested typical Stargardt disease while her two brothers presented with Stargardt disease-fundus flavimaculatus (STGD-FFM) and her two sisters demonstrated a peculiar phenotype overlapping Stargardt disease and cone-rod dystrophy; their phenotypic manifestation corresponded well with ERG groups I, II and III, respectively. This uncommon occurrence of an age-related decline in ERG amplitude and worsening of fundus changes is suggestive of a grading pattern in Stargardt disease. Their two cousins in family B, displayed the STGD-FFM phenotype. Despite clinically similar STGD-FFM patterns in both families, age of onset and progression of the phenotype in family B differed from family A.
  
  
  CONCLUSIONS
  This is the first report on phenotypic variation of Stargardt disease in a large Tunisian family. Regarding phenotype and severity of visual symptoms, family A demonstrated Stargardt disease at various stages of progression. In addition, STGD-FFM appeared to be an independent clinical entity in family B. These findings imply that further parameters are required to classify Stargardt's disease.
authors.affiliation: Department of Ophthalmology, Hedi Rais Institute of Ophthalmology, Tunis, Tunisia ; Ocular Genetics Research Unit (UR17/04), Hedi Rais Institute of Ophthalmology, Tunis, Tunisia.
authors.forename: Leila
authors.initials: L
authors.lastname: El Matri
authors.affiliation: Ocular Genetics Research Unit (UR17/04), Hedi Rais Institute of Ophthalmology, Tunis, Tunisia ; Molecular Investigation of Genetic Orphan Diseases Unit, Institut Pasteur, Tunis, Tunisia.
authors.forename: Farah
authors.initials: F
authors.lastname: Ouechtati
authors.affiliation: Department of Ophthalmology, Hedi Rais Institute of Ophthalmology, Tunis, Tunisia ; Ocular Genetics Research Unit (UR17/04), Hedi Rais Institute of Ophthalmology, Tunis, Tunisia.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Chebil
authors.affiliation: Department of Ophthalmology, Hedi Rais Institute of Ophthalmology, Tunis, Tunisia ; Ocular Genetics Research Unit (UR17/04), Hedi Rais Institute of Ophthalmology, Tunis, Tunisia.
authors.forename: Leila
authors.initials: L
authors.lastname: Largueche
authors.affiliation: Molecular Investigation of Genetic Orphan Diseases Unit, Institut Pasteur, Tunis, Tunisia.
authors.forename: Sonia
authors.initials: S
authors.lastname: Abdelhak
keywords: Classification; Fundus Flavimaculatus; Interfamilial; Intrafamilial; Prognosis; Progression; Stargardt Disease