Hi ! Your wife is possibly having some kind of chronic problem of the intestines. Does she have any low grade fever
specially in the evenings ? Does any of her family members or with whom they are friendly recieved any long term treatment of a few months for chronic cough
or any other chronic problem ? I would suggest you to talk to your family physician to investigate her in the lines of tuberculosis
of intestines which is a common extra pulmonary tubercular infection
in India. even though all the investigations may look to be normal, intestinal tuberculosis may exist, and only a therapeutic trial may prove it to be the case. However, you must take the advice of your family physician before deciding on any such treatment. A barium meal
follow through or a CECT abdomen may also be done to know the status of intestines and other organs of the abdomen. Your family physician can suggest you name of a gastroenterologist at Hyderabad. Hope this will help you out in dealing with your wife's condition. Good luck.