Hello,
Thanks for posting your query.

Tubercular cold abscesses of chest wall are not common and are known to recurr even if drained unlike bacterial abscesses.Antituberculous combination chemotherapy should be recommended as initial treatment. In your husbands case the treatment given seems appropriate however it may take a couple of months for the complete resolution of his symptoms since the anti Tb treatment .
The swelling noticed or abscess is actually a collection of immune cells of the body which react and fight against the TB organism ( bacilli),so it's not like the usual pus which is formed in other acute infections which resolve fast once drained.
In Tb many times drainage of pus is not even attempted and the abscess sometimes resolve gradually with anti tb medicines alone .
However in bone tb and especially chest wall Tb surgical procedures like drainage or rib resection might aid in faster recovery . So please do not worry . Tb being a slow and longstanding infection does take time to heal but is very much a curable disease . With appropriate treatment your husband will be absolutely fine in few months .
So do not lose hope .
Meanwhile your doctor might send the abscess material obtained by drainage or aspiration for pathological tests like microscopy and culture etc which might help in guiding the further management .
Hope this answers your query.
Wishing your husband a speedy recovery .
Regards

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