Serum immunoglobulins in psoriatic erythroderma.

The cause of psoriatic erythroderma (PE) is still unknown. Elevation of serum IgE has been reported in erythroderma, and as serum hyper-IgE is Th2 cell dominated it is of interest to investigate the serum IgE level in PE. In this study, the level of immunoglobulins in the sera of PE patients was analysed by a retrospective case-control study using psoriasis vulgaris (PV) patients as controls. The PE and PV patients were matched in a 1:3 pattern: the first three age and sex matched PV inpatients were selected. All of the subjects were nonatopic and without allergic history. The serum IgE level was found to be elevated in 81.3% of the PE group, which is much higher than that (6.3%) of the controls (odds ratio, 65.0; 95% CI, 11.7-361.2; P < 0.001; chi2 test). The mean level of serum IgE was much higher in the PE group (272.38 +/- 207.63 IU/mL vs. 53.20 +/- 86.05 IU/mL, P < 0.001, Student's t-test). No differences were found for other immunoglobulins. These results suggest that in PE the Th1/Th2 cell imbalance may be switched from Th1 dominant to Th2 dominant. The exact role of serum IgE in PE should be investigated further.