Retinitis pigmentosa and common variable immunodeficiency disease: associated or separate?
In the case presented by Starr et al, in which the sister of the proband in the second generation was diagnosed with CVID, an ophthalmic examination or an electroretinogram (ERG), (which objectively measures the electrical activity of the photoreceptor cells in the retina) might detect a very mild form of RP. If the two diseases are in fact associated or on the same gene that is being transmitted in this family, this would help elucidate the mode of transmission. Sometimes, a characteristic of a severe X-linked disease is the inability to reproduce--possibly evidenced by the diagnosis of the Sertoli-only syndrome in the proband in the case reported here. This previously unreported finding that RP and CVID could occur concomitantly may point to mechanisms that underlie the etiology of either disease. Moreover, it has been hypothesized from a study done in a small group of patients with RP that the elevated amounts of antigens observed in their sera result from the degeneration of the retina and this, in turn, might exacerbate the immune and inflammatory responses observed. (10) Identifying candidate genes and environmental factors that could be used in the development of appropriate targets may be a useful initial step for both preventative and therapeutic interventions in diseases such as retinitis pigmentosa and common variable immunodeficiency disease.
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Margaret M. DeAngelis, PhD
From the Department of Ophthalmology, Harvard Medical School, Massachusetts Eye and Ear Infirmary, Boston, MA.
Reprint requests to Margaret M. DeAngelis, PhD, Harvard Medical School, Department of Ophthalmology, Massachusetts Eye and Ear Infirmary, 243 Charles Street, Boston, MA 02114. Email: firstname.lastname@example.org
Accepted June 6, 2006.