Idiopathic anaphylactoid reactions. A clinical summary
S. R. Sale, P. A. Greenberger and R. Patterson
Thirty-one patients, aged 6 to 78 years, with anaphylactoid reactions of
unknown cause were retrospectively evaluated. All of the patients had
life-threatening hypotension, wheezing or upper airway obstruction, and
simultaneous angioedema or urticaria. Twenty-six patients also had episodes
of angioedema or urticaria alone. In nine patients the initial episode was
the most severe. In 16 of 18 patients, medications were effective in
controlling or reducing the severity of the symptoms. In ten patients, the
reactions were always self-limited and no medications were needed. No
deaths occurred in 210 anaphylactoid attacks during 164 patient-years.
Remissions lasting more than one year occurred in seven patients.
Laboratory studies, food diaries, and skin tests were not helpful in
establishing an etiology, although atopy was present in 12 of 15 patients
tested.