Yeah I guess I need to talk to the dermo.
I first saw something on my big toenails before DS -- less striped and more blotchy and powdery. I Googled and found the fungus you did
@DianaCox . My manicurist for 12 years insisted I did not have fungus and was upset that I might be suggesting that her shop was anything less than clean. (She is a CRAZY clean germaphobe. She says if she sees fungus on a client's nails she makes them leave.) Never the less I tried the People's Pharmacy remedy of dipping my toenails in Listerine and rubbing in Vick's Vaporub but noticed no difference after several months. (I keep polish on them so I don't have to look at it.) It has never progressed beyond the big toes or turned yellow. They do not look anywhere as icky as the Google photo.
The fingernails are completely different: not powdery, just white lines. Everything I find on vertical white stripes says it's just (gag) AGE related. But it came on almost overnight on all fingernails so "age" doesn't make sense to me. I keep my nails polished so, like toes, don't have to look at them. (They're not ridged even though it may look like that in the photo. My mother's finger and toe nails were very ridged, thick and yellow. Glad I don't have that.)
Another pill to take...