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.     

Asthma and IgE levels in rural and urban communities of The Gambia

Two hundred and thirty-one randomly selected schoolchildren and adults from rural Gambian villages showed no evidence of asthma, nor could any case of asthma be found in three rural villages with a total population of over 1200. In contrast, asthmatic patients were identified without difficulty in the capital town. The geometric mean serum IgE level of 131 rural schoolchildren was 962 u/ml, whereas that of sixty age-matched urban schoolchildren was 368 u/ml (P<0.001). Forty-four asthmatics, all from the capital town, had a mean serum IgE level of 405 u/ml, not significantly different from that of urban schoolchildren. Twenty-one asthmatics showed skin sensitivity to house dust mite antigen, but their IgE levels were not significantly higher than asthmatics without skin sensitivity. The incidence of positive skin tests to mite antigen amongst normal Gambians, both rural and urban, was around 1%. The findings are discussed in relation to the hypothesis that parasite-induced IgE may prevent the development of atopic illness.