Thanks for the query.
Red blistering bumps on knuckles and patch on wrist
Along with photosensitivity
is suggestive of a collagen
can be considered as a diagnosis.
Please get your ANA profile done.
This may be helpful in diagnosing your condition.
Please meet a dermatologist
for exact diagnosis and treatment.
Let me know if you have any other doubt.
you can ask a direct question to me on this forum, following the below link.
Wishing you a good health.