Fig. 2.

The follicles of psoriasis tonsils are smaller and have smaller germinal centres than hypertrophic and recurrently infected tonsils. Hypertrophic tonsils (HT, a) are tightly packed with enlarged follicles with noticeably large germinal centres. The recurrently infected tonsils (RT, b) and the psoriasis tonsils (PST, c) contain follicles of various sizes. Measurements of the follicular circumference revealed that PST follicles were smaller than the HT (d, P < 0·0001) and RT follicles (d, P = 0·008). The germinal centres were also significantly smaller in comparison to the other groups (e, HT, P < 0·001; RT, P = 0·0014), while the mantle zone of both RT (f, P = 0·02) and PST (f, P = 0·009) tonsils was smaller than in the HT group. All measurements were made in mm² at ×25 magnification in two to four visual fields per tonsil. Statistical significance calculated with Student's t-test or Mann–Whitney U-test, as appropriate; n.s.: not significant.