Background: In the 1970s, there were 2 reports of a late-onset adverse reaction during bolus infusions of benzyl penicillin, characterized by short-lived symptoms, most commonly abdominal pain. The mechanism is not known. We set out to further characterize this reaction.
Methods: We conducted a prospective observational study of all adult patients receiving bolus intravenous (IV) beta-lactam antibiotics under the care of our Outpatient IV Antibiotic Service from 1 August 2007 to 31 January 2010, focusing on those who developed infusion-related symptoms.
Results: During the 30-month study, 11 of the 163 patients (7%) treated with bolus IV beta-lactam antibiotics developed a late-onset infusion-related adverse reaction. Six of 30 patients (20%) treated with benzyl penicillin developed this adverse reaction compared to 5 of 133 (4%) treated with any other beta-lactam antibiotic (p = 0.006). The median duration of beta-lactam antibiotic before reaction onset was 25 days. Abdominal pain occurred in 9 patients (82%), fever in 3 (27%), and rash in 5 (45%). Seven patients (64%) developed a combination of thrombocytopenia, neutropenia, and/or lymphopenia and 6 (55%), elevated liver enzymes.
Conclusions: This adverse reaction, occurring late during prolonged IV bolus beta-lactam treatment, is most often characterized by short-lived abdominal pain occurring at the time of infusion and is more common in patients receiving benzyl penicillin. It is frequently associated with cytopenias and elevated liver enzymes. It may have both immunological and non-immunological mechanisms.