Early transition to avacopan from glucocorticoids applied during induction therapy for microscopic polyangiitis with rapidly progressive glomerulonephritis.

Antineutrophil cytoplasmic antibody-associated vasculitis (AAV) is a systemic autoimmune disease characterized by necrotizing inflammation of small blood vessels. Glucocorticoids (GC) in combination with rituximab or cyclophosphamide can reduce AAV-related mortality and rescue renal function. However, several side effects associated with these agents, including GC toxicity, are concerning. Avacopan, an inhibitor of the C5a receptor, is now available for AAV treatment and is expected to mitigate GC toxicity. We present a case of myeloperoxidase-antineutrophil cytoplasmic antibody (MPO-ANCA)-positive microscopic polyangiitis (MPA) with rapidly progressive glomerulonephritis treated with an early switch from GC to avacopan in combination with rituximab during induction therapy. Over a 6-month treatment period, clinical remission was achieved and maintained without infection or elevated liver enzyme levels. Efficacy and safety data regarding avacopan for AAV induction therapy remain limited. Therefore, more case reports are required to clarify the role of avacopan in AAV induction and maintenance therapy. Since the MPO-ANCA titer remained elevated despite the clinical remission of AAV in this case, the ANCA titer may not necessarily be a reliable biomarker for predicting AAV relapse when avacopan is applied as an induction therapy for AAV.

Pancreatitis with pancreatic tail swelling associated with incretin-based therapies detected radiologically in two cases of diabetic patients with end-stage renal disease.

We herein report two cases of pancreatitis associated with incretin-based therapies in end-stage renal disease (ESRD) patients undergoing dialysis. A 75-year-old woman with a history of liraglutide use and a 68-year-old man with a history of vildagliptin use both presented with nausea. They showed elevated levels of pancreatic enzymes and pancreatic tail swelling on CT. Their symptoms improved after discontinuing the drugs. In the absence of any obvious secondary causes of pancreatitis, we believe that the pancreatitis observed in these cases was associated with the incretin-based therapies. Few reports have been published on the safety and efficacy of incretin-based therapies in ESRD patients, and it remains uncertain whether the changes in the pancreas observed in the present cases are characteristic of ESRD patients.

Determination of hydroxyl radical photoproduction rates in natural waters.

The photochemical formation rates of hydroxyl radicals (OH radicals) in river water and seawater were determined by a simple, rapid and sensitive benzene probe method, in which phenol formed by the reaction between benzene and photochemically-generated OH radicals was analyzed by on-line preconcentration HPLC. The OH radical formation rates from well-known OH radical sources, such as nitrate, nitrite and hydrogen peroxide, were in good agreement with those reported previously. River water samples containing high concentrations of nitrate and nitrite were found to show high OH radical formation rates. Ten to 80% of the OH radical formation in river water and seawater was due to the photolysis of nitrate and nitrite, but OH radical formation from hydrogen peroxide was negligible. The OH radical formation from unknown sources other than nitrate, nitrite and hydrogen peroxide was strongly correlated to the amount of fluorescent matter.