I am now into my third month of IvIg infusions. My immunologist, on the basis of finding a SAMD9L mutation (variant of uncertain significance, but likely to be disruptive of function), recommended that I get an IvIg dosage that is "immuno-regulatory" because testing revealed I am both immunodeficient (don't raise enough antibodies to vaccines) and potentially autoimmune due to symptoms of intense burning feet, ankles and calves, and very evident inflammation (red, hot & swollen feet & ankles). So far, I am not noticing any reduction in symptoms, but I recognize that it will be months before I might begin to notice any change. In the meantime, my pain doctors won't prescribe even the lowest dose of opioid because of other meds I'm on, so I have very fragmented sleep, which only makes the pain worse. In addition to my SAMD9L mutation, I also have pathogenic mutations in my SDHB and FBXL4 gene. All three of these genes affect the function of mitochondria (the energy producing organelles found in all cells), and I have been diagnosed with mitochondrial dysfunction. Does anyone in the group have mutations in genes encoding mitochondrial proteins or been diagnosed with mitochondrial dysfunction? Has anyone been diagnosed with erythromelalgia?