Association of thyroid disease with retinitis pigmentosa and gyrate atrophy

Gyrate Atrophy of the Choroid and Retina: A Review

Gyrate atrophy (GA) of the choroid and retina is a rare autosomal recessive genetic condition characterized by elevation of the plasma level of the amino acid ornithine due to deficiency of the enzyme ornithine ketoacid aminotransferase. Accumulation of ornithine occurs in various body tissues but leads primarily to characteristic ophthalmic manifestations including myopia, cataract, progressive chorioretinal atrophy, and macular changes. Patients usually present with night blindness that starts in the first decade of life followed by visual field constriction and eventually diminution of the central visual acuity and blindness. The condition has been reported worldwide and its differential diagnosis is broad and includes choroideremia and retinitis pigmentosa. Treatment currently depends on life-long dietary modifications including restriction of the amino acid arginine in diet. This article describes in detail the pathogenesis, clinical features, multimodal imaging findings, and treatment options for GA of the choroid and retina and its complications.

Hashimoto's encephalopathy in association with retinitis pigmentosa - First reported case

Hashimoto's Encephalopathy (HE), also known as steroid responsive encephalopathy associated with autoimmune thyroiditis (SREAT), is a proteiform disorder known for its wide spectrum of presentations from subtle neuropsychiatric manifestations, movement disorders, seizures, stroke-like episodes to coma. Here, we report a case of HE which initially masqueraded as bipolar affective disorder (BPAD) and ultimately progressed to generalized tonic clonic seizures and coma. Although SREAT is characterized by exquisite responsive to steroid, in our case it was unresponsive to pulse methylprednisolone therapy. Rapid recovery was noted with intravenous immunoglobulin (IVIG) therapy. This case was also peculiar for its association with non-sydnromic retinitis pigmetosa (RP). To the best of our knowledge, this was the first reported case of HE which was associated with RP.

A review of the immunologic findings observed in retinitis pigmentosa

Most patients suffering from retinitis pigmentosa (RP) inherit the disorder; however, the immune-pathologic features associated with this disease have yet to be extensively studied. Six reports correlate antiretinal immune activity with vision deterioration in RP patients. Some of these patients have sporadic RP that occurs in excess of expected gene segregation during inheritance. The hypothesis that a primary immune-mediated disease process occurs in this sporadic group is supported by significant associations of RP with autoimmune endocrinopathies and other immune-related conditions or factors; however, no immunologic difference regarding RP family history is reported in the peripheral blood studies of RP patients. Twenty-one percent to 51% of RP patients display antiretinal antibodies, whereas 19-58% have antiretinal lymphocyte reactivity to retinal extract, and 60-85% have activated T cells. Mutations in animal models of RP have been shown to cause endoplasmic reticulum stress that may initiate immunopathology for genetic RP, but oxidative stress also encourages immune cytotoxicity. In addition, necrotic cell death is evident, which promotes inflammatory conditions. We review mechanisms and evidence for an occult inflammation in genetic RP and examine reports of efficacy in retarding RP progression with anti-inflammatory agents in clinical trials.

Identification by array screening of altered nm23-M2/PuF mRNA expression in mouse retinal degeneration

In the rd/rd mouse model of inherited retinal degeneration, the majority of photoreceptors die apoptotically between postnatal age (P)10 and 20 days, during which period the inner retina appears morphologically unaffected. To examine mRNA changes associated with the degeneration, we performed differential screening of 588 arrayed murine cDNAs using probes reverse-transcribed from P8 predegenerative and control mouse retinal RNAs. We detected altered expression of the gene encoding nm23-M2, a member of the family of nucleoside diphosphate kinases implicated in diverse processes including metastasis suppression and transcriptional regulation. Retinal nm23 mRNA levels increased during degeneration while control levels decreased over age-matched time-points. In situ hybridization showed the high level of expression at P20 in rd/rd was concentrated in the retinal ganglion cells. Previous studies have indicated upregulation of the stress-response related gene alphaB-crystallin in the rd/rd inner retina, and increased nm23 levels may be a component of this response to photoreceptor loss and altered retinal architecture.