Small Bowel Resection.

Dear Sir,
My Son now almost 19 years old had undergone an small bowel resection when he was 15 years old. Only 60 cm of Small bowel is remaining as informed by doctor. He has not gained significant weight after that and he was on intermittent dose of supplement vitamin and iron pills. He was leading almost normal life. Since last fortnight he is complaining of abdominal pain and breathlessness. After CT scan, dilation of small bowel and elongated villi is observed which is normal as informed. He is also having intermittent high fever. Tests for malaria, jaundice are normal. Lever is reported to be inflammated slightly. Doctor has started anti malarial pills. Please advise probable causes. We reside in India. Waiting eagerly for a reply.  Yours Sincerely - Rajesh.