X-Linked Retinitis Pigmentosa – XLRP
Retinitis pigmentosa (RP) is an inherited retinal dystrophy caused by the loss of photoreceptors and characterized by retinal pigment deposits visible on fundus examination. Affected individuals first experience night blindness, followed by reduction of the peripheral visual field and, sometimes, loss of central vision late in the course of the disease and eventually leading to blindness after several decades. Signs and symptoms often first appear in childhood, but severe visual problems do not usually develop until early adulthood. In some cases, RP is characterized by cone-rod dystrophy, in which the decrease in visual acuity predominates over the visual field loss. RP is usually nonsyndromic but there are also many syndromic forms. The main risk factor is a family history of retinitis pigmentosa.
Indications for genetic testing:
1. Confirmation of clinical diagnosis
2. Determination of female carriers
3. Genetic counseling
Genetic testing for x-linked retinitis pigmentosa is preferred in the male patients/families with nonsyndromic retinitis pigmentosa and with family history of x-linked retinitis pigmentosa.