Retinitis Pigmentosa 25

Background and History: 

Retinitis pigmentosa (RP) consists of a large group of disorders resulting from a progressive loss of the rods and cones in the retina.  These are the cells that respond to light and send signals to the brain that enable us to see.  More than 100 mutant genes have been identified as responsible for these hereditary disorders and there is considerable variation in onset and progression of symptoms.  The disease usually is present as an isolated eye disease but syndromal forms also occur in which there is a similar disease of the retina in association with other problems elsewhere in the body.

Clinical Correlations: 

The first symptoms consist of difficulty seeing at night followed by constriction of side vision and these typically appear in young adults but they are often detectable in the first decade of life.  Often patients complain of sensitivity to light together with color vision difficulties.  About this time fine vision is lost as well and some patients are legally blind by the 6th decade.  Eye examinations usually show clumps of black pigment in the retina while the optic nerve that connects the retina to the brain often shows damage as well.  Cataracts occur in some adult patients. 


This type of retinitis pigmentosa is inherited in an autosomal recessive pattern.  Parents who carry one copy of a specific mutation are usually clinically normal but when both pass the same mutant gene to their offspring, they will have this form of retinitis pigmentosa.  Each such child has a 1 in 4 chance of inheriting the condition.

Other forms of retinitis pigmentosa are caused by genes on the X chromosome and appear primarily in males.

Diagnosis and Prognosis: 

The disease is usually diagnosed by an ophthalmologist based on the symptoms and the appearance of the retina.  An electrical test called an ERG is often used to confirm the diagnosis.  There are no signs of disease outside of the eye in most cases.  Lifespan is not impacted.

Low vision aids and mobility training can be great benefit.  Cataract surgery is indicated in patients when the lens opacities interfere with vision.

Additional Information