Background: Diabetic retinopathy improved in three patients with renal insufficiency after a rise in hematocrit induced by administration of recombinant erythropoietin. The change involved significant resorption of hard exudates in patients who were not eligible to receive laser treatment.
Methods: Three patients with diabetic nephropathy had the associated chronic anemia of renal insufficiency. In each patient, diabetic retinopathy with foveal/parafoveal hard exudates (but no clinically significant macular edema) was initially evaluated ophthalmoscopically. Fluorescein angiography demonstrated a low-grade diffuse leakage pattern. Treatment with subcutaneous recombinant erythropoietin (4000 IU twice weekly) was initiated within 1 to 3 months of initial evaluation. The resolution of hard exudates was observed on ophthalmoscopic examination and graded fundus photography (ETDRS seven standard field).
Results: Within 6 months of initiation of erythropoietin treatment, a substantial reduction of exudate was observed in all three patients, the hematocrit having increased from a mean of 21% to a mean of 33% (a mean increase of 33% in each patient). Visual acuity improved in two patients and stabilized in the other. Follow-up fluorescein angiographic examination demonstrated no change in the leakage pattern.
Conclusion: Although no direct cause and effect relationship can be established, raising the red cell mass by treatment with recombinant erythropoietin may serve as adjunctive treatment of diabetic retinopathy in patients with diabetic renal insufficiency.