D. (1946–2008) died suddenly in April, 2008.”
“Introduction After the recognition of autoimmune pancreatitis (AIP) as an IgG4-related disease [1], similar lesions in other organs have attracted much attention. IgG4-related kidney disease (IgG4-RKD) was first reported as a complication or an extrapancreatic manifestation of AIP in 2004 [2, 3]. In the early reported cases, Protein Tyrosine Kinase inhibitor the development of renal dysfunction and/or proteinuria during the clinical course of AIP was the clue to the presence of renal involvement,

and renal biopsy revealed tubulointerstitial nephritis (TIN) and fibrosis with dense infiltration of IgG4-positive plasma cells [2–4]. Thereafter, incidentally-detected Eltanexor purchase IgG4-RKD cases in the course of close examination of AIP [5–7] or chronic sclerosing sialadenitis and dacryoadenitis [8] using enhanced computed tomography (CT) have been additionally accumulated. Recently, IgG4-RKD without AIP or

chronic sclerosing sialadenitis and dacryoadenitis has also been reported [9–11]. Against this background of detection of IgG4-RKD with the kidney being the first recognized organ of IgG4-related buy PD0332991 disease [9–11], demand for practical diagnostic criteria for IgG4-RKD has been growing. To meet this demand and spread recognition of IgG4-RKD among nephrologists and other clinical practitioners, we organized a working group in the Japanese Society of Nephrology (JSN) consisting of specialists in clinical nephrology, renal pathology, clinical immunology and rheumatology. This report describes our proposal for a diagnostic algorithm and the diagnostic criteria for IgG4-RKD prepared by this working group. Methods Patients Between 2004 and 2011, we identified 41 patients with IgG4-RKD in Kanazawa University Hospital, Nagaoka Red Cross Hospital, Niigata University Hospital,

Sapporo Medical University Hospital, and Fukuoka Oxymatrine University Hospital. Nine patients [3 Churg–Strauss syndrome; 2 IgG4-RKD without TIN with decreased renal function; 1 Sjögren’s syndrome (SS) with TIN; 1 minimal change nephrotic syndrome; 1 allergic disease with hypocomplementemia; 1 relapsing polychondritis] were selected as a negative control. Written informed consent for all data and samples was obtained from each patient. The diagnosis of IgG4-RKD was made principally based on the histologic and immunohistochemical findings of the kidney or other organs with the support of a comprehensive analysis of the clinical picture including elevated serum IgG4 levels, and final clinical judgment was left to the observers at each hospital who had sufficient experience in IgG4-related disease and clinical nephrology.