A study finds that several factors, including admission to the ICU and use of systemic corticosteroids, can increase the likelihood of a negative histamine response.
UCLA researchers used a retrospective case-and-control design study and obtained data from UCLA inpatient penicillin skin testing records from 2010 to 2013. Histamine control showed a negative reaction among 52 patients in the cohort. An additional 125 patients with normal histamine response served as controls.
The researchers sought to determine if any factors were associated with a negative histamine test response.
Being admitted to the ICU (OR = 8.18; 95% CI, 3.22-20.76) was associated with a significant difference between patients with negative histamine response (73.1%) and controls (33.6%). Systemic corticosteroid use also was more likely to result in a negative histamine response (OR = 3.76; 95% CI, 1.3-10.92), and each 1-year increase in a patient’s age also correlated with greater odds of a negative response (OR = 1.04; 95% CI, 1.01-1.07).