Leopard spot retinal pigmentation in infancy indicating a peroxisomal disorder

Leopard-like retinopathy and severe early-onset portal hypertension expand the phenotype of KARS1-related syndrome: a case report

BACKGROUND

Mutations in lysyl-tRNA synthetase (KARS1), an enzyme that charges tRNA with the amino acid lysine in both the cytoplasm and mitochondria, have been associated thus far with autosomal recessive Charcot-Marie-Tooth type CMTRIB, hearing loss type DFNB89, and mitochondrial encephalohepatopathy (MEH) featuring neurodevelopmental disorders with microcephaly, white matter changes, and cardiac and hepatic failure in less than 30 patients.

CASE PRESENTATION

We report the clinical, biochemical and molecular findings of a 14-month-old girl with severe MEH compatible clinical features, profound sensorineural hearing loss, leopard spot retinopathy, pancytopenia, and advanced liver disease with portal hypertension leading to death at the age of 30 months.

CONCLUSIONS

Whole exome sequencing identified two rare variants in KARS1 gene. Our report expands the allelic and clinical features of tRNA synthase disorders. Moreover, with our report we confirm the usefulness of WES as first tier diagnostic method in infants with complex multisystem phenotypes.

Ophthalmic manifestations of Heimler syndrome due to PEX6 mutations

BACKGROUND/AIMS

Pigmentary retinal dystrophy and macular dystrophy have been previously reported in Heimler syndrome due to mutations in PEX1. Here we reported the ocular manifestations in Heimler syndrome due to mutations in PEX6.

MATERIALS AND METHODS

Medical records were reviewed to identify patient demographics, ophthalmic and systemic findings, and results of diagnostic testing including whole genome sequencing.

RESULTS

Patient 1 is 12-year-old boy with a novel mutation c.275T>G (p.Val92Gly) and known mutation c.1802G>A (p.Arg601Gln) in PEX6. Patient 2 is a 7-year-old girl with the same known c.1802G>A (p.Arg601Gln) mutation and another novel missense mutation c.296G>T (p.Arg99Leu). Both patients exhibited a pigmentary retinopathy. Visual acuity in patient 1 was 20/80 and 20/25 following treatment of intraretinal cystoid spaces with carbonic anhydrase inhibitors, while patient 2 had visual acuity of 20/20 in both eyes without intraretinal cysts. Fundus autofluorescence showed a multitude of hyperfluorescent deposits in the paramacular area of both eyes. OCTs revealed significant depletion of photoreceptors in both patients and macular intraretinal cystoid spaces in one patient. Full field electroretinograms showed normal or abnormal photopic but normal scotopic responses. Multifocal electroretinograms were abnormal.

CONCLUSIONS

Heimler syndrome due to biallelic PEX6 mutations demonstrates a macular dystrophy with characteristic fundus autofluorescence and may be complicated by intraretinal cystoid spaces.

Giraffe or leopard spot chorioretinopathy as an outstanding finding: case report and literature review

PURPOSE

Presentation of two typical cases with characteristic leopard retinopathy secondary to bilateral diffuse uveal melanocytic proliferation (BDUMP) and idiopathic uveal effusion syndrome (IUES) and brief review of the literature about leopard spot retinopathy.

CASE REPORT

A 43-year-old women, who was a known case of ovarian carcinoma, referred with gradual bilateral visual loss. In ophthalmic examination, subretinal fluid, multiple patchy subretinal hyperpigmented lesions and leopard spot chorioretinopathy were evident in her both eyes. Fluorescein angiography showed multiple nummular hyperfluorescent lesions surrounded by zones of hypofluorescence. Spectral domain optical coherence tomography revealed increased retinal thickness, subretinal fluid and RPE irregularities in both eyes. Enhanced depth imaging OCT (EDI-OCT) showed bilateral subfoveal choroidal thickening. During next 2-year follow-up, she underwent cataract surgery and later on developed neovascular glaucoma in her both eyes. The second case was a 45-year-old man who had developed decreased visual acuity in his left eye for 3 years. Anterior segment examination was unremarkable, and both eyes had normal intraocular pressure. No vitreous inflammation was observed. Fundoscopy revealed diffuse exudative retinal detachment in his left eye. Fluorescein angiography showed leopard spot retinopathy of posterior pole, and EDI-OCT disclosed subfoveal choroidal thickening. After exclusion of other causes of exudative retinal detachment and with diagnosis of IUES, he underwent intravitreal triamcinolone injection (2 mg) which improved his final vision to 20/40.

CONCLUSION

Leopard spot retinopathy is an uncommon but clinically distinct manifestation of various disorders. BDUMP may present with leopard spot retinopathy, anterior uveal tract involvement and neovascular glaucoma. As EDI-OCT showed involvement and increased thickening of choroid in both cases of BDUMP and IUES, it may be better to consider such cases as leopard chorioretinopathy and categorize these entities as a member of pachychoroid pigment retinopathy disorders.

Novel retinal findings in peroxisomal biogenesis disorders

Peroxisomal biogenesis disorders are caused by disruption of long chain fatty acid metabolism due to mutations in PEX genes. Individuals with these disorders often have vision loss due to optic atrophy and pigmentary retinopathy. We report an unusual retinal manifestation of peroxisomal biogenesis disorder.

SD-OCT patterns of the different stages of choroidal metastases

A diagnosis of choroidal metastasis is based on the patient's clinical history, the tumor's ophthalmoscopic appearance, and instrumental imaging results such as ultrasonography, fluorescein angiography, fundus autofluorescence, indocyanine green angiography, and optical coherence tomography. Spectral-domain optical coherence tomography (SD-OCT) has provided additional useful information for clinical diagnosis: a pattern of hyperintense irregular spots in the context of the photoreceptor layer and in the retinal pigment epithelium, subretinal fluid, and marked irregularity of the retinal pigment epithelium with thickening and gross undulation. The authors describe a case of bilateral choroidal metastasis presenting peculiar SD-OCT features acquired at different stages. They emphasize the central role of SD-OCT among instrumental imaging procedures and for final successful diagnosis.

Florid polyclonal lymphoid follicular hyperplasia presenting as leopard spot retinopathy

PURPOSE

To describe a case of leopard spot retinopathy associated with a systemic polyclonal lymphoproliferative disorder. Other described causes of this clinical finding are reviewed.

METHODS

Case report. A previously healthy 50-year-old white male presented with decreased vision. Examination showed leopard spot retinopathy. He underwent ophthalmic and body imaging, laboratory workup, and biopsy of a lymph node and lacrimal gland.

RESULTS

The workup revealed a systemic polyclonal lymphoproliferative disorder which involved the orbit, lymph nodes, pancreas, kidney, and choroid.

CONCLUSION

Leopard spot retinopathy is a clinical description associated with multiple etiologies. Choroidal infiltration related to a systemic polyclonal lymphoproliferative disorder is one cause.

Plasmalogens in the retina: In situ hybridization of dihydroxyacetone phosphate acyltransferase (DHAP-AT) – the first enzyme involved in their biosynthesis – and comparative study of retinal and retinal pigment epithelial lipid composition

Plasmalogens (Pls) are phospholipids containing a vinyl-ether bond in the sn-1 position of the glycerol backbone. The physiological role of Pls is still enigmatic, especially within the eye where their deficiency leads to developmental abnormalities. In order to learn more about the functions of Pls in the posterior eye, we evaluated retinal Pl content as well as the expression of the first enzyme involved in Pls biosynthesis, dihydroxyacetone phosphate acyltransferase (DHAP-AT) in the retina. In situ hybridization of DHAP-AT mRNA was performed on rat eye sections. The Pl contents of calf retina and retinal pigment epithelium (RPE) samples were determined by high-performance liquid chromatography, thin-layer chromatography, and gas chromatography. DHAP-AT was highly expressed in the inner segment of photoreceptors and in the RPE, suggesting two distinct sites for Pl biosynthesis. Plasmenyl-ethanolamine was the prominent class of Pls in both neural retina and RPE (28-29% of the total phospho-ethanolamine-glycerides). According to the nature of the alkenyl residue linked to the sn-1 position of Pls, the most striking finding was the greater proportion of octadecanal-aldehyde in the sn-1 position of plasmenyl-ethanolamine of the neural retina compared to all the other classes of Pls in the neural retina and the RPE. These findings might be relevant to the biological functions of Pls against oxidative stress and in the formation of lipid rafts.