Gout is a disease caused by the deposition of monosodium urate monohydrate (MSU) crystals. Precise mechanisms underlying the initiation of acute gout, however, are not known. Recent investigations provided novel evidence in the pathology of acute gout. A number of studies indicated that MSU crystals can act as a "danger signal" which resembles exogenous adjuvants, and toll-like receptor(TLR)-mediated pathways and/or MyD88-dependent IL-1 receptor pathways are involved in acute gout. Up-regulation of the triggering receptor expressed on myeloid cells 1(TREM-1) in phagocytes by the stimulation with MSU crystals has been demonstrated. Furthermore, pathological significance of NALP 3 inflammasome in gout has been also demonstrated. These findings provide a new insight into the mechanisms underlying the initiation of MSU crystal-induced acute inflammation.