Thanks for the query to H.C.M.. forum.
Since within 2 years he got 25 kg weight ,really pretty high.
You mentioned that there was dilation for achalasia .
There develops difficulty in swallowing esophagus
due to achalasia.
It might happened that he was under weight before dilation.
Now weight may be slight high but not as think , so please mention the weight and height , age of your husband.
2 nd possibility may be fluid retention due to one kidney
, so please get in blood for serum creatinine
and blood urea .
If kidney function normal need not to worry.
So deal accordingly.
Good luck for your husband.