Recruitment of immature neutrophils in peripheral blood following leukocytapheresis therapy for rheumatoid arthritis.

The objective of this study is to evaluate the cellular mechanism underlying filtration leukocytapheresis (LCAP) therapy for the treatment of rheumatoid arthritis (RA). Thirteen patients with refractory RA each underwent three sessions of LCAP. Before (pre-) and after (post-) the completion of the first LCAP session, peripheral blood was sampled and analyzed for neutrophil surface markers using flow cytometry. The surface antigens of peripheral blood mononuclear cells (PBMCs) and neutrophils obtained at pre- and post-LCAP were then analyzed using a fluorescence-activated cell sorter. The American College of Rheumatology's criterion of a 20% improvement was achieved in six patients, but not in the other seven patients, after LCAP therapy. The post-LCAP number of blood band form neutrophils with a bone marrow phenotype (CD49d(dim+), low density) was higher among the responders than among the nonresponders, suggesting an association between the clinical response and the recruitment of bone-marrow-derived neutrophils. After the nonspecific absorption of WBCs during a 1-h Cellsorba procedure, the number of PBMCs was consistently decreased, although the number of neutrophils that were affected by removal plus recruitment varied in a manner that was independent of efficacy. In contrast, the emergence of immature neutrophils in the peripheral blood was characteristic of the effective therapies. These cells were found after the 1st session of responders and also found following sessions of LCAPs. Immature neutrophils, which may be recruited from the bone marrow in the peripheral blood after the first session of LCAP, can predict the clinical efficacy of subsequent LCAP sessions.

[A case report of segmental arterial mediolysis].

We report a case of 58-year-old woman with a ruptured dissecting aneurysm of the middle colic artery (MCA). Her initial manifestation was sudden and severe right-sided abdominal pain, followed by hemorrhagic shock and acute anemia. Abdominal CT showed a right retroperitoneal hemorrhage. Emergency catheter angiography and therapeutic coil embolization of the middle colic artery were performed and micro aneurysms were enhanced in the jejunal branch. Immunological tests showed nothing abnormal. Follow-up angiography after 3 months showed that the micro aneurysms had disappeared. The patient was diagnosed as having segmental arterial mediolysis (SAM), because no definitive evidence of atherosclerosis and polyarteritis nodosa were observed. SAM is a rare disease of unknown etiology. The arterial lesions developing in elderly patients are characterized by segmental lysis of the abdominal splanchnic arteries resulting in aneurysms, and acute bleeding in a skip pattern. Multiple aneurysms and abdominal pain due to the rupture of these lesions in SAM resemble the clinical findings in polyarteritis nodosa. Differential diagnosis of the two diseases is important because steroid therapy is not beneficial for SAM.