Need diagnosis.Elementary school aged female.  3 weeks of epigastric abdominal

Need diagnosis.
Elementary school aged female.  3 weeks of epigastric abdominal pain, seen by PCP and at urgent care. Has undergone ultra sound showing no findings.  KUB, no findings.  She has been treated with Pepcid, Protonix, Metamucil, Maalox and Simethicone.  No help.  the pain is sharp, nonradiating and waxes and wanes with no specific exacerbating or relieving factors. Minor nausea only. No vomiting, diarrhea, dysuria, hematuria, fevers, chest pain, cough, cold or SOB.  Last bowel movement was today,  soft formed stool.  Patient does not yet menstruate.
When the pain comes on the child is driven to tears.  Mother feels helpless.  Full workup initiated including CT Abdomen Pelvis with contrast performed- noted to be negative for any acute findings.  (no evidence of constipation either).  EKG is normal sinus rhythm without arrhythmia.  All laboratory studies are negative (normal electrolytes, LFTs, kidney function tests, unremarkable CBC, negative lipase) EXCEPT for elevated troponin.  Repeat troponin and ekg performed.  EKG remains unremarkable.  Second troponin 4 hours later is still high.