Hello,

Thanks for posting your query.

Recurrent canker sores per se don't cause a rise in the ESR. However, canker sores can be a part of the systemic illness which is causing both the ESR to rise as well as the canker sores. Systemic diseases like rheumatoid arthritis or SLE can result in a high ESR, canker sores and joint pains.
XXXXXXX is a blood test which should be done as these diseases are autoimmune diseases and XXXXXXX is usually positive. RA factor and ds-DNA are other tests which need to be done to rule out these diseases.

Multiple myeloma is another disease which needs to be ruled out. A serum protein electrophoresis should be done which is the diagnostic test of choice and shows an abnormal protein in the blood.

Please do consult a rheumatologist for the same.

Hope this answers your query. If you have additional questions or follow up queries then please do not hesitate in writing to us. I will be happy to answer your queries.
Wishing you good health.

Regards.

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