[Early biological markers of anaphylactoid reactions occurring during anesthesia]

[Anaphylactic and anaphylactoid reactions occurring during anaesthesia in France. Seventh epidemiologic survey (January 2001-December 2002)]

OBJECTIVES

Hypersensitivity reactions IgE-mediated (anaphylaxis) or non-IgE-mediated (anaphylactoid) reactions occurring during anaesthesia remain a major cause of concern for anaesthesiologists, since these reactions remain usually unpredictable, may be potentially life-threatening even when appropriately treated. The authors report the results of the last 2-year survey (2001, 2002) of such reactions conducted in France by the GERAP (groupe d'etude des reactions anaphylactoides peranesthesiques), and compare these results with their previous published surveys.

METHODS

Between January 1, 2001 to December 31, 2002, 712 patients who experienced immune-mediated (anaphylaxis) or non-immune-mediated (anaphylactoid) reactions were referred to one of the 40 allergo-anaesthesia centres members of the GERAP. Anaphylaxis was diagnosed on the basis of clinical history, tryptase measurements during the adverse reaction, and skin tests and/or specific IgE assay.

RESULTS

Anaphylactic and anaphylactoid reactions were diagnosed in 491 cases (69%) and 221 cases (31%), respectively. The most common causes of anaphylaxis were neuromuscular blocking agents (NMBA) (n=271, 55%), latex (n=112, 22.3%), and antibiotics (n=74, 14.7%). Succinylcholine (n=102, 37.6%) and rocuronium (n=71, 26.2%) were the most frequently incriminated NMBAs. Cross-reactivity between NMBAs was observed in 63.4 % of cases of anaphylaxis to a NMBA. No difference was observed between anaphylactoid and anaphylactic reactions when the incidences of atopy, food, or drug intolerance were compared. However atopy, asthma and food allergy were significantly more frequent in case of latex allergy, when compared with NMBA allergy. Clinical manifestations were more severe in anaphylaxis. The positive predictive value of tryptase measurement for the diagnosis of anaphylaxis was 95.3%, the negative predictive value 49%. The diagnostic value of specific neuromuscular blocking agent IgE assays was confirmed.

CONCLUSION

Our results further corroborate the need for systematic screening in case of immediate hypersensitivity reaction during anaesthesia and for the constitution of allergo-anaesthesia centres to provide expert advice to anaesthesiologists and allergologists.

Histamine and tryptase levels in patients with acute allergic reactions: An emergency department-based study

BACKGROUND

Emergency department visits for acute allergic reactions are common. Although the diagnosis and classification of these allergic reactions is primarily empiric, it is not always clear whether certain signs and symptoms constitute systemic mediator release syndromes, such as anaphylaxis, and thus may warrant more aggressive therapy or follow-up.

OBJECTIVE

We sought to determine associations between various clinical signs and symptoms with both plasma histamine levels and serum tryptase levels in adult patients presenting to an emergency department with acute allergic syndromes. The clinical correlates of raised beta-tryptase levels were also investigated.

METHODS

Ninety-seven adult emergency department patients were prospectively studied by using a questionnaire, physical examination, and serum-plasma sampling. Plasma histamine and serum total and beta-tryptase levels were determined. Clinical groupings were compared for mediator levels by using simple and multivariate analysis.

RESULTS

Elevated levels of plasma histamine (>10 nmol/L) and serum total tryptase (>15 ng/mL) were observed in 42 and 20 patients, respectively. Detectable beta-tryptase (>/=1 ng/mL) was observed in 23 patients, including 15 of the patients with elevated total tryptase levels. Suspected food allergy incidences and the duration of reaction were similar in patients with increased histamine levels and in patients with increased tryptase levels. Increased total tryptase levels, histamine levels, or both were observed in some patients who did not have airway, cardiovascular, or abdominal signs. Histamine levels correlated better with clinical signs than tryptase levels. Histamine elevations (>10 nmol/L) were observed more frequently in patients characterized by the following clinical signs in univariate analysis: the presence of urticaria, more extensive erythema, abnormal abdominal findings, and wheezing. Total tryptase increases were observed more frequently only in patients with urticaria. Histamine levels correlated with initial heart rates. In multivariate analysis the extent of urticaria was the best single predictor of plasma histamine levels and of either an elevated histamine or tryptase level. Detectable beta-tryptase levels were observed in some patients who had neither elevated total tryptase nor elevated histamine levels. Unlike patients without detectable beta-tryptase levels, patients who had detectable beta-tryptase levels had a significant correlation between total tryptase and histamine levels (P <.05).

CONCLUSIONS

Raised histamine and, less commonly, raised tryptase levels are observed in almost 50% of patients presenting to emergency departments with acute allergic reactions. Some cases associated with systemic mediator release do not have classical features of severe anaphylaxis, such as hypotension or tachycardia. The lack of total tryptase elevations in many patients with elevated plasma histamine levels suggests basophil involvement. The clinical utility of beta-tryptase determinations in the evaluation of acute allergic reactions needs further study.

[Anaphylactic shock during the use of high doses of aprotinin in cardiac surgery]

A 77-year-old man was admitted for mitral valve replacement, 46 days after a failed conservative mitral surgery where he received high-dose aprotinin. Twenty minutes after induction of anaesthesia, 250 UPh E of aprotinin were infused intravenously; before the end of this infusion, bronchospasm, systemic hypotension and generalized rash were noted. Immediate treatment included intravenous adrenaline and methylprednisolone; cardiovascular stability was restored after 10 minutes. Immediate histamine liberation was confirmed by the analysis of the time course of the clinical events, a previous contact and positive skin tests. Aprotinin has the antigenic molecular structure of natural proteins. Since 1987, it is used in cardiac surgery to reduce postoperative blood loss: to prevent serious allergic reactions to aprotinin, it is necessary, in patients known to have had previous aprotinin therapy, to perform skin testing with diluted aprotinin before infusion.