I have this condition on my upper arms that started around the time of PATM.
https://www.mayoclinic.org/diseases-conditions/keratosis-pilaris/symptoms-causes/syc-20351149
Some people say that it is related to celiac disease, but there is no empirical evidence to show that its true.
Upper chest upper arm
Sometimes torso lower lateral abdominal
Mostly upper chest
Only after I binged on a sweet or a carb