Cicatricial pemphigoid: serial titres of circulating IgG and IgA antibasement membrane antibodies correlate with disease activity

We have recently shown in a cohort of patients (n = 67) with mucous membran e pemphigoid, 63 of whom had cicatricial pemphigoid (CP), that the presence of both IgG and IgA circulating antibasement membrane zone antibodies was associated with a more severe and persistent disease. In this study we soug ht to ascertain whether in CP, serial titres of IgG and IgA might provide a reliable marker of disease activity, Serum titres for IgG and IgA antibodi es were assayed at 6- to 12-monthly intervals in 56 patients over 32.2 +/- 20.3 (mean +/- SD) months. Antibody titres were correlated with the clinica l score recorded at each follow-up visit. Sequential titres for both IgG (P < 0.001) and IgA (P = 0.015) were significantly associated with variations in disease activity, Greatest improvement was seen in patients with the gr eatest change in either IgG or IgA antibody titre. We suggest that serial a ntibody titres may therefore be useful in the assessment and management of CP.