Altered hemolysis in single radial hemolysis from a single serum sample as an indicator of recent primary rubella virus infection

Abstract

The quality of hemolysis in the single radial hemolysis (SRH) test was observed to be altered in a small proportion (5.7%) of sera (N = 9628) studied for rubella rubella antibodies. Three different types of altered hemolysis were identified. Two of these types, the "soft margin" (SM) or the "soft zone" (SZ), occurred singly or in combination in 97% of paired sera (N = 321) taken 3-30 days after primary rubella infection (diagnostic seroconversion). For comparison, diagnostic increases of rubella antibodies (N = 77), including both primary and reinfections, contained these types of altered hemolysis in 80% of the cases. Of the remaining 20% of the samples (N = 15), rubella antibodies of IgM class were looked for in seven cases but not found. After primary rubella, SZ was always present in the first serum sample and disappeared rapidly within 20 days while SM persisted longer. The predictive value of the different types of hemolysis was estimated from 96 primary sera, which had altered hemolysis. In this material, SZ was followed by a diagnostic increase of antibodies in 87% of the cases; the prognostic value of the SM was significant but lower. These data show that the appearance of SM or SZ in a single serum sample is a useful marker of recent primary rubella. On the other hand, a normal hemolysis in SRH can be used to exclude recent primary rubella, but not reinfection, with a high degree of probability.

Maturation of immunoglobulin G avidity after rubella vaccination studied by an enzyme linked immunosorbent assay (Avidity‐ELISA) and by haemolysis typing

“…In the semiquantitative (haemolysis typing) assay, sera were categorized in three groups according to the sharpness of the outer edge of the haemolytic zone in RH, as described earlier [Hedman et al, 1984[Hedman et al, , 1986Hedman and Seppala, 19881. Briefly, the "soft" zone has a characteristically diffuse outer margin.…”

Togaviridae: Rubella Virus

“…Such interference with lysis in SRH may be caused by a "blocking factor" (Champsaur, 1983;Kangro et al, 1983). Hazy zones of hemolysis may also be indicative of recent rubella infection (Hedman et al, 1984;Morgan-Capner et aI., 1982). The sensitivity of the SRH can be increased by enlarging the size of the serum well, double-filling the well, and reducing the concentration of RBCs employed (Morgan-Capner, 1983).…”

Standardization of Assays That Detect Anti-Rubella Virus IgG Antibodies

“…Like HAI, CFT was labor intensive and imprecise and detected both IgG and IgM. Radial hemolysis (RH), which detects the ability of the antibody-antigen reaction to lyse erythrocytes immobilized in agar, was used to detect and semiquantify rubella virus antibodies (43)(44)(45)(46)(47). In contrast to HAI and CFT, RH detects only IgG, in particular, subclasses 1 and 3.…”