PTU-079 Non-invasive testing is diagnostic and prognostic in intestinal graft versus host disease

Abstract

Introduction Intestinal graft versus host disease (iGVHD) is a debilitating and sometimes fatal consequence of bone marrow transplantation 1 . Malnutrition and profuse diarrhoea are common. The diagnosis is often based on clinical criteria alone and intestinal biopsies are frequently negative. 1,2 Even after successful treatment, iGVHD can relapse and reliable disease monitoring is unavailable. We conducted this prospective study to evaluate the diagnostic accuracy of the xylose/rhamnose/lactulose small bowel permeability test (SBPT) and faecal calprotectin (FC) in the work-up of patients with suspected iGVHD. Method Prospective data was collected on all patients referred for endoscopic investigation of suspected iGVHD at KCH, from Jan–Dec 2014. All patients underwent OGD and colonoscopy to at least the caecum, with serial intestinal biopsies taken. Samples were collected for SBPT and FC. Infection and other pathologies were excluded with extensive testing. SBPT and FC results were compared to biopsy results. Results 15 patients had positive intestinal biopsies (PB) with 9 negative (NB). SBPT was unavailable in 2, and FC in 1 patient in each group. SBPT was abnormal in 1/7 NB and in 11/13 PB. The sensitivity (Sn) and specificity (Sp) for SBPT in the diagnosis of iGVHD was 84.6% and 85.7% respectively; PPV 91.7%. FC was high in 2/8 NB and 9/14 PB, returning Sn 64.2% and Sp 75%. Addition of the two tests reduced sensitivity and specificity further. Mortality was high in the PB group (6/14, 43% – exclusively from gram-negative sepsis +/- multi-organ failure). FC was elevated >300 mcg/g in 5/6 deaths and 2/8 survivors. Conclusion SBPT appears to be a highly sensitive and specific marker of iGVHD. A high FC does not appear to be related to iGVHD itself, but may predict severe disease and mortality. These non-invasive tests are simple and cheap and may serve to assist clinicians in the investigation and management of this debilitating condition. Disclosure of interest None Declared. References Ferrara JL, et al . Lancet 2009;373:1550–1561 Ross WA, Couriel D. Curr Opin Gastroenterol . 2005; 21 :64–69