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1.According to the history - the features suggestive of infective aetiology ( bacterial infection).
2.Tenderness and collection seems localised infection in first possibilities.
3.The next possible cause could be
enlarged lymph node with complicated aetiology can not be ruled out - lymph nodal enlargement is generally seen after any systemic / local infection / inflammation.
4.Finally form any gland (
thyroid,submandibular,parotid) -
ultrasound neck will help to analyse the nature of lump and its source and extensions.
5.After that by nature an FNAC - fine needle aspiration may or may not be necessary - jut a course of antibiotic might help.
Needs to examine first. Good luck.
Hope it helps you. Wish you a good health.
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