Major criteria:
(1) anasarca (pleural effusion, ascites, general edema)
(2) platelet count <= 100,000 per µL, excluding myelosuppressive therapy
(3) systemic inflammation (FUO > 37.5°C and/or serum CRP >= 2 mg/dL)
Minor criteria:
(1) Castleman disease-like features on lymph node biopsy
(2) reticulin myelofibrosis and/or increased megakaryocytes in the bone marrow
(3) mild organomegaly (liver, spleen, lymph nodes)
(4) progressive renal insufficiency
Criteria for diagnosis - all of the following:
(1) all 3 of the major criteria
(2) >= 2 of the minor criteria
(3) exclusion of malignancy, autoimmune disease, infection, POEMS syndrome, cirrhosis, TTP and HUS
Additional findings:
(1) serum IgG concentration should be < 3,000 mg/dL
(2) there should not be an obvious monoclonal protein
(3) serum LDH should not be elevated
(4) serum ALP will usually be elevated
(5) hepatosplenomegaly should be mild
(6) lymph nodes are usually less than 1.5 cm in diameter
Conditions that may be difficult to exclude:
(1) Castleman disease
(2) immune thrombocytopenia (ITP)
