Cal is a heterodimer, which is composed of MRP 8 and MRP 14. It exists in neutrophils cytoplasm and expressed on mononuclear cell membranes. Cal is acute phase proteins, it has a well stable phase about one week in human faeces, it is determined to be a inflammatory bowel disease marker. The kit is a simple, visual semiqualitative test that detects cal in human faeces, it has high detection sensitivity and strong specificity. The test based on high specificit double antibodies sandwich reaction principle and gold immunochromatographic assay analysis technics, it can give a result within 15 minutes.