Clinical examination
The
clinical data of each subject was collected from the hospital records.
These data included age, sex, and laboratory tests. Individual subjects
were subjected to routine laboratory tests for full blood cell counts,
C-reactive protein (CRP), erythrocyte sedimentationrate (ESR),
N-terminal pronatriuretic peptide (NT-proBNP), and the concentrations of
serum immunoglobulins (Ig)G, M, A and complement (C)3, 4 by a
biochemistry automatic analyzer (Roche Diagnostics, Branchburg, USA) and
scatterred turbidimetry on a Siemens special protein analysis instrument
(Siemens Healthcare Diagnostics Products, GmbH, Germany).