Mountain cedar pollinosis: can it occur in non-atopics?

Abstract

In 1984 Ramirez postulated the existance of two subgroups of patients with Mountain Cedar (MC) pollinosis. One subgroup had a single positive skin test (SPST) to MC only, lacked other atopic diseases, and required prolonged MC exposure to develop the disease. The second subgroup had multiple positive skin tests (MPST) in addition to MC, had other atopic diseases, and developed clinical symptoms after a shorter period of MC exposure. To validate these findings, and to explore the clinical and immunologic differences between these two subgroups, 13 SPST and nine MPST patients underwent immunotherapy with MC pollen extract. Six SPST and ten non-allergic controls did not receive immunotherapy. MC specific IgE (sIgE), MC sIgG, and MC sIgG subclasses were measured by ELISA pre and intra season. Symptom Medication Score (SMS) were measured during the MC season. SPST patients had a significantly lower baseline sIgE than MPST patients, 2.1 IU/ml versus 22.3 IU/ml, p = 0.023, and were also older than MPST patients, 52.4 versus 32.2 years, p less than 0.001. Baseline MC sIgG and MC sIgG subclass antibody levels were similar in both patient groups. SMS were lower in treated SPST patients compared to treated MPST patients, p less than 0.01, but in vitro responses to immunotherapy were not significantly different between the two groups. MC sIgE, MC sIgG, MC sIgG1 and MC sIgG4 rose in both treated groups. MC sIgG1 (but not MC sIgG4) rose during the MC season in both non-immunotherapy groups.(ABSTRACT TRUNCATED AT 250 WORDS)