If the individuals on L-DOPA did develop AMD, the age of occurrence of the disease was about eight years later than for those without L-DOPA treatment, and for wet AMD, it was about five years later. At least two further reviews summarize a small “proof of concept” clinical research study by Figueroa et al. in 2021 that evaluated whether individuals who already had wet AMD could receive improvement if they took oral L-DOPA. The summary given by both reviews indicates that oral L-DOPA could cause retinal fluid to decrease by almost 30% even without standard anti-VEGF treatment, and this was accompanied by improvement in visual acuity. In addition, there was about a 50% reduction in the need for anti-VEGF injections. RPE and L-DOPA in amelioration of wet AMD
The retinal pigment epithelium (RPE) (see diagram) has an essential role in the eye. It secretes a large variety of factors including at least 22 proteins important in maintaining the structure, function and micro-environments on the two sides of the RPE. (The two sides of the RPE include the choroid side, where blood vessels form and bring nourishment to the eye, and the photoreceptor side, with rods and cones that receive light signals.) In particular, the RPE secretes vascular endothelial growth factor (VEGF) at its basement membrane, with the VEGF reaching the choriocapillaris to maintain proper blood vessel formation in the choroid region. Many factors, including genetic factors, hypoxia, oxidative stress and inflammatory stressors, may cause pathologic over-production of VEGF by the RPE.
A low level of neutrophils (a specific type of white blood cell) may also be found in some individuals with Waldenström macroglobulinemia.Chemistry tests include lactate dehydrogenase (LDH) levels, uric acid levels, erythrocyte sedimentation rate (ESR), kidney and liver function, total protein levels, and an albumin-to-globulin ratio. The ESR and uric acid level may be elevated. Creatinine is occasionally elevated and electrolytes are occasionally abnormal. A high blood calcium level is noted in approximately 4% of patients. The LDH level is frequently elevated, indicating the extent of Waldenström macroglobulinemia–related tissue involvement. Rheumatoid factor, cryoglobulins, direct antiglobulin test and cold agglutinin titre results can be positive. Beta-2 microglobulin and C-reactive protein test results are not specific for Waldenström macroglobulinemia. Beta-2 microglobulin is elevated in proportion to tumor mass. Coagulation abnormalities may be present. Prothrombin time, activated partial thromboplastin time, thrombin time, and fibrinogen tests should be performed. Platelet aggregation studies are optional. Serum protein electrophoresis results indicate evidence of a monoclonal spike but cannot establish the spike as IgM. An M component with beta-to-gamma mobility is highly suggestive of Waldenström macroglobulinemia. Immunoelectrophoresis and immunofixation studies help identify the type of immunoglobulin, the clonality of the light chain, and the monoclonality and quantitation of the paraprotein. High-resolution electrophoresis and serum and urine immunofixation are recommended to help identify and characterize the monoclonal IgM paraprotein. The light chain of the monoclonal protein is usually the kappa light chain. At times, patients with Waldenström macroglobulinemia may exhibit more than one M protein. Plasma viscosity must be measured.