From a neutrophilic synovial tissue infiltrate to a challenging case of rheumatoid arthritis.

The herein report illustrates how a synovial tissue heavily infiltrated by neutrophils in the first weeks of arthritis, can evolve in few months to a synovial infiltration by lymphocytes with a characteristic pattern of rheumatoid arthritis (RA). This observation suggests a critical initial role of neutrophils in RA onset, which is eventually surpassed by the activation of the adaptive immune system. In addition, this patient, despite the absence of rheumatoid factors and anti-cyclic citrullinated peptide antibodies, progressed to a highly destructive and disabling disease, that was only controlled adequately with rituximab, due to the lack of response to methotrexate and serious adverse effects with TNF blockers therapy.