bone spicula pigmentation

Retinitis Pigmentosa 80

Clinical Characteristics
Ocular Features: 

Night blindness is an early symptom which may be noted in early childhood.  Vision loss can be documented in early childhood and progressively worsens to hand motions or light perception by the 3rd to 5th generation.  The fundus appearance has been described as normal in 1-year old patients but retinal pigmentary changes and arteriolar changes are evident in some children by the age of 2 years.  Typical bone spicule pigmentary changes have been described in some older patients.  Staring at lights (photophilia) has been noted in children under 1 year of age while eye-rubbing (oculodigital sign) may be seen soon thereafter.  Nystagmus is often present.

ERG responses are greatly diminished or nonrecordable.  Rods are more severely affected than cones.  OCT shows loss of inner and outer segments of photoreceptors.

Systemic Features: 

Systemic signs seem variable but full evaluations have not been done in all patients.  Mild developmental delay has been reported in some individuals and significant childhood onset hearing loss has been documented in at least one person.  Radiography of the hands revealed cone-shaped phalangeal epiphyses in 5 probands and one proband had short fingers in one study.


Homozygous or compound heterozygous mutations in the IFT140 gene (16p13.3) segregates with the phenotype as expected for an autosomal recessive disorder.

The same gene is mutated in Short-Rib Thoracic Dysplasia 9 (266920) in which similar digital and retinal changes are seen.  However, renal, hepatic, and additional skeletal disease are also present.  These may be the same conditions pending further elucidation of the phenotypes.

Autosomal recessive
Treatment Options: 

No treatment has been reported for the general disorder.  However, low vision aids should be offered to young people, especially during school years.

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