Hi,
Noted your history of a sore at the nostril, oozing fluid that crusts later, now spreading and painful.
The commonest cause I can think about is one of the following:
Erysipelas is a
cutaneous infection.
Collumellitis if infection of skin and mucus lining.
Eczema.
Rhinosporidiosis.
This can be perfectly diagnosed only by the ENT Surgeon and may be by
second opinion of a
Dermatologist.
Hence consult your ENT and a Dermatologist.
Investigations as would advised for.
It is possible that you will be given a course of an antibiotic and anti-allergic for some time to see the results, if positive then continue on.
If no effect then a biopsy and further management as per the cause will be done.
Sometimes
autoimmune disease may need to be ruled out.
Hope I have answered your query. Let me know if I can assist you further.
Regards,
Dr. T. Chandrakant, ENT and General Surgeon