Why this case matters
Retinitis pigmentosa (RP) is commonly recognized by symptoms such as night blindness, sensitivity to light, and progressive loss of peripheral vision. However, similar symptoms and retinal test results can sometimes arise alongside unusual structural changes in the eye. A 2026 case report in Cureus describes one such situation: a man with generalized rod-cone dysfunction resembling RP who also had numerous fluid-filled elevations beneath the retinal pigment epithelium (RPE) in both eyes.
For people living with RP, families seeking answers, and researchers studying inherited retinal disease, this report is an important reminder that diagnosis depends on more than one test or symptom. Careful imaging, visual-field testing, and electroretinography (ERG) can reveal a more complete picture of retinal health—and may identify features that do not fit a typical RP presentation.
An unusual combination of findings
The report describes a 55-year-old man referred because of abnormalities seen in both eyes during a retinal examination. He reported a paracentral scotoma, meaning an area of reduced or missing vision near the center of his visual field. He also experienced photophobia, or light sensitivity, and nyctalopia, difficulty seeing in dim light or darkness.
Despite these symptoms, his central visual acuity was excellent: 20/16 in the right eye and 20/13 in the left eye. This contrast is clinically meaningful. A person can retain sharp central vision while having substantial difficulty with low-light vision, peripheral vision, or sensitivity to bright light.
Fundus examination showed many round, transparent serous retinal pigment epithelial detachments (PEDs) in both eyes. The RPE is a vital layer of cells that supports the light-sensing photoreceptors—the rods and cones. In a serous PED, fluid collects beneath the RPE, creating a localized elevation. In this case, the PEDs extended from the posterior pole, the central back portion of the eye, toward the equator of the retina.
The clinicians also observed RPE atrophy near the major retinal blood-vessel arcades. Atrophy refers to areas where tissue has thinned or been lost. Together, the widespread PEDs and areas of RPE atrophy created a retinal appearance that was not typical of classic RP alone.
What the retinal tests revealed
Multimodal imaging helped characterize both the structural and functional aspects of the condition. Optical coherence tomography (OCT), a noninvasive scan that provides cross-sectional views of the retina, showed multiple PEDs with dark, low-reflectivity spaces inside them. OCT also showed outer retinal atrophy while sparing the fovea, the small central region responsible for the sharpest detailed vision. Foveal sparing may help explain why the patient’s visual acuity remained so strong.
Fundus autofluorescence imaging added further information about the health of the RPE. The margins of the PEDs were hyperautofluorescent, meaning they appeared brighter than surrounding tissue. Areas of atrophy were hypoautofluorescent, or darker. These patterns provided a map of where the RPE was structurally altered.
Functional testing showed widespread retinal impairment. Full-field ERG measures electrical responses generated by the retina after flashes of light. The patient had severely reduced to non-recordable rod and combined rod-cone responses. Cone responses and 30-Hz flicker responses were also markedly reduced and delayed. In accessible terms, both major photoreceptor systems were affected, with especially severe rod dysfunction.
Goldmann perimetry, a visual-field test, demonstrated ring scotomas in both eyes. A ring scotoma is a circular region of missing or reduced vision surrounding the center of the visual field. This pattern, together with night blindness and the ERG findings, supported generalized rod-cone dysfunction resembling RP.
Why the distinction is important
The authors did not identify a specific cause for the combined PEDs and rod-cone dysfunction. An extensive workup for infectious and inflammatory causes was unremarkable. The case was therefore described as generalized rod-cone dysfunction resembling RP rather than as a confirmed inherited RP diagnosis.
That distinction matters. RP is a group of inherited retinal disorders, often associated with disease-causing variants in specific genes. This report does not provide genetic findings or establish that the patient had an inherited retinal disease. Instead, it documents a rare clinical coexistence: bilateral multifocal serous PEDs alongside retinal dysfunction that produced an RP-like functional pattern.
For patients and families, the broader lesson is that similar symptoms do not always point to one underlying cause. Night blindness, ring-shaped visual-field loss, and abnormal ERG responses are highly informative, but they are interpreted alongside retinal imaging, clinical history, and testing for other possible explanations.
Implications for management and future research
The patient was monitored conservatively and remained stable during two years of observation. No treatment approach was reported because no underlying cause was identified and the condition did not show progression during follow-up.
The case highlights the value of repeated monitoring with complementary tools. OCT can follow PED structure and outer retinal integrity; autofluorescence can track RPE-related changes; ERG can assess generalized rod and cone function; and visual-field testing can document how functional vision changes over time.
For the research community, reports like this help define the full range of retinal disorders that can resemble RP. Future studies may clarify whether some unusual combinations of RPE abnormalities and rod-cone dysfunction have shared biological pathways, distinct genetic contributors, or currently unrecognized causes. As retinal imaging and functional testing become increasingly precise, clinicians and researchers will be better positioned to separate similar-looking conditions and guide care according to each person’s retinal profile.