Intraoperative anaphylaxis to bacitracin during pacemaker change and laser lead extraction

Prevention of pacemaker infections with perioperative antimicrobial treatment: an in vitro study

AIMS

The antimicrobial treatment of pacemaker casings with antiseptics (povidone-iodine or octenidine dihydrochloride) or antibiotics (vancomycin, daptomycin, cefuroxime, Tazobac, or nebacetin) was analysed in vitro for its biocompatibility and efficacy in preventing the bacterial adhesion of Staphylococcus epidermidis, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli to cardiac-implantable electrophysiological devices (CIEDs).

METHODS AND RESULTS

Titan platelets (0.4 cm²) cut from pacemaker casings were impregnated with seven different antimicrobial solutions: two antiseptics and five antibiotics. Subsequently, they were challenged with bacterial contamination by four test strains over a 24 h incubation period. Bacterial adherence was quantified using the colony-forming-unit method after cell recovery with sonication and examined with confocal laser scanning electron microscopy. Simultaneously, the biocompatibility of the antimicrobial impregnation was assessed using pre-treated titan platelets in a culture of human fibroblasts, skeletal myoblasts, and microvascular endothelial cells. After a 48 h incubation, cell vitality was measured using the 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H/tetrazolium monosodium (WST-8) assay. The immersion of pacemaker casings in antiseptic or antibiotic solutions applies an antimicrobial coating that can significantly reduce bacterial adhesion. The studied impregnations differed in their antimicrobial efficacy and toxicity.

CONCLUSION

Compared with the two antiseptics and the other tested antibiotics, nebacetin showed the best ratio of efficacy to toxicity. Nebacetin showed good in vitro antibacterial activity against both Gram-positive and Gram-negative pathogens without impairing human cell vitality. It is a safe and effective candidate for CIED impregnation.

Drug allergy: an updated practice parameter

Adverse drug reactions (ADRs) result in major health problems in the United States in both the inpatient and outpatient setting. ADRs are broadly categorized into predictable (type A and unpredictable (type B) reactions. Predictable reactions are usually dose dependent, are related to the known pharmacologic actions of the drug, and occur in otherwise healthy individuals, They are estimated to comprise approximately 80% of all ADRs. Unpredictable are generally dose independent, are unrelated to the pharmacologic actions of the drug, and occur only in susceptible individuals. Unpredictable reactions are subdivided into drug intolerance, drug idiosyncrasy, drug allergy, and pseudoallergic reactions. Both type A and B reactions may be influenced by genetic predisposition of the patient

Detection of IgE antibodies to bacitracin using a commercially available streptavidin-linked solid phase in a patient with anaphylaxis to triple antibiotic ointment

BACKGROUND

Bacitracin is a commonly used topical antibiotic that has on occasion been reported to cause anaphylaxis. Evidence of the role of bacitracin specific IgE in such reactions has been demonstrated by skin testing. Because of the potential for provoking a systemic reaction by skin testing, it would be advantageous to develop an in vitro test for bacitracin specific IgE.

OBJECTIVE

To report our experience coupling bacitracin to a solid phase and using it to detect specific IgE to bacitracin by fluorescent enzyme immunoassay.

METHODS

A patient with a history of recurrent anaphylaxis that developed after application of triple antibiotic ointment to an open wound underwent skin testing with triple antibiotic ointment. Bacitracin was biotinylated and coupled to streptavidin ImmunoCAPs. IgE against bacitracin in the patient's serum was detected by fluorescent enzyme immunoassay.

RESULTS

Topical application of triple antibiotic ointment to intact skin produced a 7 X 8-mm wheal with pseudopods. IgE against bacitracin was detected using biotinylated bacitracin-streptavidin ImmunoCAPs at a level of approximately 0.6 KUA/L and confirmed with ImmunoCAPs using direct coupling of bacitracin to the solid phase.

CONCLUSIONS

We demonstrate the presence of IgE antibodies to bacitracin in a patient with anaphylaxis to triple antibiotic ointment using a recently described procedure for producing custom allergen solid phases for immunoassay.

Diagnostic Value of Tryptase in Anaphylaxis and Mastocytosis

Serum (or plasma) levels of total and mature tryptase measurements are recommended in the diagnostic evaluation of systemic anaphylaxis and systemic mastocytosis, but their interpretation must be considered in the context of a complete workup of each patient. Total tryptase levels generally reflect the increased burden of mast cells in patients with all forms of systemic mastocytosis (indolent systemic mastocytosis, smoldering systemic mastocytosis, systemic mastocytosis associated with a hematologic clonal non-mast cell disorder, aggressive systemic mastocytosis, and mast cell leukemia) and the decreased burden of mast cells associated with cytoreductive therapies in these disorders. Causes of an elevated total tryptase level other than systemic mastocytosis must be considered, however, and include systemic anaphylaxis, acute myelocytic leukemia, various myelodysplastic syndromes, hypereosinophilic syndrome associated with the FLP1L1-PDGFRA mutation, end-stage renal failure, and treatment of onchocerciasis. Mature (beta) tryptase levels generally reflect the magnitude of mast cell activation and are elevated during most cases of systemic anaphylaxis, particularly with parenteral exposure to the inciting agent.