Congenital Hypertrophy of the Retinal Pigment Epithelium (CHRPE)

Congenital Hypertrophy of the Retinal Pigment Epithelium (CHRPE)
SYMPTOMS Typically asymptomatic
May sometimes be associated with visual field defects especially if the CHRPE is located in the posterior pole and lacunae is present
SIGNS There are three types of CHRPE
Solitary CHRPE: Typically unilateral. Ranges from 0.2-13mm in size (can be very large). Appears as a black-gray, flat, well-demarcated lesion with a distinct non-pigmented or pigmented halo and possible lacunae (areas of chorioretinal atrophy within the CHRPE due to choriocapillaris damage)
Grouped CHRPE ("Bear tracking"): Typically unilateral. Found in groups of 3 to 30 CHRPE that ranges in size from 0.1-2mm. These CHRPE are found in a sectoral orientation in one or more quadrants usually in the mid-peripheral retina or nasal to the optic nerve. Appears as black-gray, flat, well-demarcated lesions without a distinct non-pigmented or pigmented halo and without lacunae
Multiple CHRPE ("Bear tracking"): Typically bilateral with about 6 CHRPE per eye (on average) that are scattered throughout the retina and are not consistent in size and shape. Appears as black-gray, flat, well-demarcated lesions with irregular borders. The presence of a depigmented tail is commonly associated with these type of CHRPE. Lacunae and a non-pigmented or pigmented halo may also be associated with these type of CHRPE
WORK-UP Full eye exam with dilated retinal exam, Visual field, OCT, Fluorescein Angiography, Fundus Autofluorescence, Fundus photos, Infrared photos, B-scan ultrasound
TREATMENT Solitary CHRPE: No treatment is needed and the CHRPE needs to be monitored
Grouped CHRPE: No treatment is needed and the CHRPE needs to be monitored
Multiple CHRPE: No treatment is needed and the CHRPE needs to be monitored. Refer patient to PCP in order to rule out Familial Adenomatous Polyposis
FOLLOW-UP See patient back in 12 months
ADDITIONAL LAB | TESTS Solitary CHRPE: None
Grouped CHRPE: None
Multiple CHRPE: Genetic testing, Sigmoidoscopy, Colonoscopy (testing will most likely be ordered by the patient's PCP in order to rule out Familial Adenomatous Polyposis)
ETIOLOGY RPE cells are taller and more densely packed with melanosomes
DIFFERENTIAL DX Choroidal nevus, Chorioretinal scar, Chorioretinal atrophy, RPE hyperplasia
NOTES CHRPE are most commonly found in the peripheral retina but can also be found in the posterior pole and equator
When examining CHRPE with photos or fundus lens, they should still be visible when using a red-free filter
Multiple CHRPE in combination with the diagnosis of Familial Adenomatous Polyposis is called Gardner syndrome
Congenital Hypertrophy of the Retinal Pigment Epithelium (CHRPE): Retinal photo demonstrating a solitary CHRPE with almost complete lacunae https://webeye.ophth.uiowa.edu/eyeforum/atlas/pages/CHRPE-lesions.html
Posted in Ocular Conditions, Retina-Periphery