Cryoglobulinemia in the various real diseases.

Cold precipitable proteins have been reported in clinical diseases since 1933 and termed as cryoglobulins (Cg) by Lerner and Watson in 1947. Our work was designed in this paper on the frequency, nature, incidence and clinical immunopathologic significance of cryoglobulins in the various renal diseases, including lupus glomerulonephritis (SLE) ;16 cases, membranouss nephropathy (MN) m 10, IgA glomerulonephritis 16, minimal change (MC) ; 6, post-inf ec-tious glomerulonephritis ; 6, chronic glomerulonephritis a 5, membrano-proliferative glomerulonephritis ; 2, focal glomerulosclerosis (FGS) ; 2, toxemia ; 3 and normal adults ; 10.<BR> Among these kidney diseases, Cg were frequently detected in SLE (63%) MN (60%) and MC (67%) R The nature of Cg was studied by means of immunofluorescence for presence of anti-nuclear factor (ANF) . ANF from SLE patients was found in the cryoprecipitate and showed peripheral pattern in most of the cases. ANF in Cg was also found in MN patients in 10%, but was not in the other diseases.<BR> The concentrations of immunoglobulins [IgG, IgA, IgM] in Cg were measured by lasernephelometer and showed higher amount in the following order, IgG> IgA> IgM.<BR> In SLE, the degree of Cg precipitate showed the reversed correlation with the amount of serum CH₅₀, C₃, C₄ and the positive correlation with circulating immune complexes (IC) [P<0.01] <BR> No significant correlation was observed between the quantity of the immunoglobulin in Cg and the severity of the light microscopical renal findings. However the immunopathology in kidney from SLE patients who were detected Cg in their sera showed severe deposits in the mesangial area.<BR> These results suggest that the Cg seems to be of some interactions with the amount of circulating IC and the levels of complements. Moreover, the Cg have some influences in the clinical course and therapy in various kidney diseases, particularly in SLE.