Brief Answer:
Can be due to Cirrhosis with GI bleed/ deranged Kidney function or infection

Detailed Answer:

Hi,

Noted the history, seen the reports and understood the concerns about your Uncle.
There are no reports of kidney function.
Also needed is X-ray abdomen in standing position.
The causes of stomach swelling can be as follows:
Since there is development of Hepatitis, enlarged portal vein and early cirrhosis as per the papers you have provided, this can be one reason.
Kidney disease itself can cause bloating if the urea and creatinine raise as these affect the bowel.
Gastrointestinal bleeding as has been suspected can cause bloating.
Intestinal infection and so on.
Hence it is necessary to undergo further clinical evaluation, examination and investigations for proper diagnosis and proper management.

I hope this answer helps you.
Please give further feedback about the reports and progression.
Please feel free to ask for further relevant queries if you feel that there is a gap of communication.

Wishing your Uncle a good recovery.

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