Brief Answer:
Looks like infection of the lymphatic vessels.

Detailed Answer:
Hello Mr. XXXXXXX


Thank you for posting your question her eon healthcaremagic.com

I have gone through your query and understand your concern.

From your description, it appears to me that the infection in the finger has spread through the lymphatic vessels.

It would help me to get a better idea if you could click some photographs of the same and upload them along with this query.

I wouldn't be too worried if the streak is not very painful and remains as a streak or if it has started to get better with the antibiotics you have been prescribed.

Please continue the antibiotics and also apply the mupirocin ointment on the finger as well.

Please go to the emergency if you notice any of the following symptoms....

1. The streak becomes progressively wider and redder
2. The whole arm swells up and becomes painful and red
3. Fever
4. Cough, burning while passing urine, altered sensorium etc.,
5. Giddiness, blurred vision or any difficulty breathing

I hope this answers your query for now, I might be able to help you further if you upload the pictures of the area.

Wishing you speedy recovery.

Best regards

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