Abstract | BACKGROUND: We describe the case of a 47-year-old man referred to a retinal clinic and diagnosed with late-onset retinitis pigmentosa. Surprisingly, genetic testing revealed compound heterozygous pathogenic variants in GNPTG, leading to the diagnosis of the autosomal recessive lysosomal storage disorder mucolipidosis type III gamma. Mucolipidosis type III gamma is typically diagnosed during childhood due to symptoms relating to skeletal dysplasia. Retinal dystrophy is not a common phenotypic feature. CASE PRESENTATION: Ophthalmologic examination was consistent with a mild form of retinitis pigmentosa and included fundus photography, measurement of best-corrected visual acuity, optical coherence tomography, electroretinogram and visual field testing. Extraocular findings included joint restriction and pains from an early age leading to bilateral hip replacement by age 30, aortic insufficiency, and hypertension. Genetic analysis was performed by whole genome sequencing filtered for a gene panel of 325 genes associated with retinal disease. Two compound heterozygous pathogenic variants were identified in GNPTG, c.347_349del and c.607dup. The diagnosis of mucolipidosis type III gamma was confirmed biochemically by measurement of increased activities of specific lysosomal enzymes in plasma. CONCLUSION:
|
Authors | Karl De Geer, Katarzyna Mascianica, Karin Naess, Eliane Sardh, Anna Lindstrand, Erik Björck |
Journal | BMC ophthalmology
(BMC Ophthalmol)
Vol. 23
Issue 1
Pg. 394
(Sep 26 2023)
ISSN: 1471-2415 [Electronic] England |
PMID | 37752499
(Publication Type: Case Reports, Journal Article)
|
Copyright | © 2023. The Author(s). |
Chemical References |
- GNPTG protein, human
- Transferases (Other Substituted Phosphate Groups)
|
Topics |
- Male
- Humans
- Adult
- Middle Aged
- Mucolipidoses
(diagnosis, genetics)
- Whole Genome Sequencing
- Electroretinography
- Retinal Dystrophies
- Transferases (Other Substituted Phosphate Groups)
|