Methods: From 2008-2016, 27-51% of AAAAI/ACAAI members completed an annual survey of SCIT/SLIT-related SRs of varying severity (WAO Grades 1-4). Cutaneous and systemic infections were queried for 2014-2016. For 2015-2016, questions included timing of onset of SRs, waiting times, and prescription/use of epinephrine auto-injectors.
Results: Data were gathered on 54.4 million injection visits (2008-2016). Three confirmed fatalities from SCIT occurred between 2008-2016. An additional 4 confirmed fatalities occurred between 2016-2017. No infections occurred in 17.3 million injection visits (2014-2016). 25% (68/278 practices) reported waiting times of < 30 minutes. 30% (1118/3711) of SRs occurred at 20-29 minutes. 35% (1311/3711) of SRs were reported to have begun after 30 minutes, including 90 Grade 3/4 SRs; only 7 patients self-administered epinephrine. Practices always prescribing an epinephrine auto-injector (29%) did not have lower rates of Grade 3/4 SRs. There were 7 SRs among 2994 patients on non-commercial SLIT; none self-administered epinephrine. There were 26 SRs among 1761 patients on commercial SLIT; 31 patients on commercial tablets self-administered epinephrine.
Conclusions: There has been a marked, unexplained increase in SCIT-related fatalities from 2016-2017; investigation is ongoing. Concerns about SCIT-related infections have not been supported by surveillance data. Despite a high number of delayed SRs, it is not clear that prescription of epinephrine auto-injectors for SCIT improves outcomes, in part because of low rates of self-administration. SRs to commercial and non-commercial SLIT were reported.