Hi,
Noted the history about a 86 year old female having the symptoms of severe pressure in abdomen and more so under left
rib cage, she possibly has IBS and has Parkinsonism.
First of all it is important to look for the cause of her symptoms.
Hence I would advise her the following:
Consult a General Surgeon and a Gastroenterologist as an examination by a Specialists helps to find the cause clinically as you have mentioned that every possible tests have already been done.
Review Contrast enhanced CT scan of the whole abdomen and MRI of the back to see if spinal problems like slipped discs are causing secondary symptoms.
Colonoscopy as you have mentioned about possible IBS.
Avoiding stress and
anxiety may help a lot.
Intermittent
intestinal obstruction, cancer of large bowel must be ruled out considering the age of the patient.
Tests of stool for three consecutive days can find out if there is any infection or infestations and be treated as per the diagnosis found out.
Relevant tests of blood and urine.
All these will help to know the cause and thus get treated accordingly.
Hope I have answered your query. Let me know if I can assist you further.
Regards,
Dr. T. Chandrakant, General Surgeon