Hi

Thanks for asking.

Fever after six months of surgery is probably not related to the gall bladder surgery.Most of the times a major complication of the surgery is the infection leading on to fever and general ill health,but six months is a long time for this.

There are many other causes of the fever with chills like:

Urinary tract infections
Undiagnosed malaria
Stones in common bile- in this case there can be jaundice and pain as well.
Pus in the abdomen
Lung infections

I will suggest you to see a doctor as soon as possible as your father needs good investigations and proper diagnosis.

He will require blood tests, urine test, usg of abdomen, blood or urine culture and some other investigations.

Thanks.

Please let me know if you need further information.

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