Linear IgA disease of adults: association with lymphoproliferative malignancy and possible role of other triggering factors.

Seventy patients with linear IgA disease of adults were followed up for a mean of 8.5 years and all malignant diseases in this group were ascertained. There were three cases of lymphoproliferative malignancy, which constituted a significant excess over the 0.2 cases that would be expected by comparison with an age- and sex-matched population using National Cancer Registry statistics. In contrast, the non-lymphoid malignancy rate of 13% is almost identical to the expected 14%. A subgroup of 35 of the adult linear IgA disease patients were assessed with respect to the possible precipitating illnesses or drugs, as well as co-existing medical conditions. Almost one-third of patients described an event that was felt could possibly have triggered the linear IgA disease, the most frequent being non-steroidal anti-inflammatory or antibiotic drug therapy, trauma/burns and upper respiratory tract infections. However, it is difficult to determine how often the preceding event is coincidental, and how often, if at all, it is causal.