Struggling with stomach problems

[Taylor1042]

My 16 year old daughter has been suffering since April 2015 with constant nausea (but not  being sick), acid reflux, dizziness, fatigue and slow weight loss (appetite was okay) it came on all of a sudden.

She was admitted with suspected appendicitis in the September 2015 as she was having bad stomach pains/cramps sickness with a high temperature but it was diagnosed as mesenteric adenitis on a ultrasound scan. She has had a couple more episodes a few months later but never went to hospital.

Roughly from April 2016 she has had irregular bowel habits  i.e. bouts of diarrhea, loose stools to not going regularly (but not constipated) all with lots of mucus, her periods have  also stopped.

From the summer in 2016 along with the constant nausea (etc..) she has had constant stomach discomfort/cramps the irregular bowel habits (bouts of diarrhea, loose stools, mucus and not going regular) now contain blood, the stomach cramps get really bad before a bowel movement. She has slowly lost weight at the beginning even despite the fact that she was eating fine but since the stomach pains have been constant (summer 2016) her appetite has gone so the weight has significantly dropped. She also has discomfort when she eats.

She has had two endoscopy (January 2015 and January 2016) in which neither showed anything abnormal. A recent colonoscopy (February 2017) showed Melanosis Coli she has never taken any laxatives apart from the prep. She has also had a mri of her small bowel which came back clear (February 2017)She has done numerous stool tests, one of which showed raised levels of Calprotein at 113 (in December 2016). She has also been tested for Hpylori and treated for it even though it came back negative (in September 2015).

The blood test in July 2015 results showed she was very low in folic acid. The blood test in July 2016 showed she very low in vitamin D, both of which have been treated and the recent blood test came back with everything within normal range.She is currently taking a multi vitamin, 2x20mg omeprazole a day and a probiotic. She has also tried mebeverine, domperidone,pizotifen,prochlorperazine, propranolol, alimemazine none of them have helped.

Family history; my father died from bowel cancer and my brother had coeliac and ulcerative colitis (passed away).

Her total weight loss was 21kg, her bmi went down to 13 but it is slowly raising due to nourishment drinks (Fortisip Compact). She has been assessed for any eating disorders and any psychological cause that may be responsible, all came back negative which is what we expected/predicted.

This has been affecting her for coming up to 2 years now. She has not attended school since April/May 2015 and has had to withdraw from GCSEs due to of all these health issues.

She was 8lb born, normal delivery she was bottle fed and fed great no problems and was completely healthy. She had never suffered from any health issues until this began