Mast cell tryptase in anaesthetic anaphylactoid reactions

Anaphylaxis: A 2023 practice parameter update

This practice parameter update focuses on 7 areas in which there are new evidence and new recommendations. Diagnostic criteria for anaphylaxis have been revised, and patterns of anaphylaxis are defined. Measurement of serum tryptase is important for diagnosis of anaphylaxis and to identify underlying mast cell disorders. In infants and toddlers, age-specific symptoms may differ from older children and adults, patient age is not correlated with reaction severity, and anaphylaxis is unlikely to be the initial reaction to an allergen on first exposure. Different community settings for anaphylaxis require specific measures for prevention and treatment of anaphylaxis. Optimal prescribing and use of epinephrine autoinjector devices require specific counseling and training of patients and caregivers, including when and how to administer the epinephrine autoinjector and whether and when to call 911. If epinephrine is used promptly, immediate activation of emergency medical services may not be required if the patient experiences a prompt, complete, and durable response. For most medical indications, the risk of stopping or changing beta-blocker or angiotensin-converting enzyme inhibitor medication may exceed the risk of more severe anaphylaxis if the medication is continued, especially in patients with insect sting anaphylaxis. Evaluation for mastocytosis, including a bone marrow biopsy, should be considered for adult patients with severe insect sting anaphylaxis or recurrent idiopathic anaphylaxis. After perioperative anaphylaxis, repeat anesthesia may proceed in the context of shared decision-making and based on the history and results of diagnostic evaluation with skin tests or in vitro tests when available, and supervised challenge when necessary.

Ghrelin Expression in Mast Cells of Infant Lung with Respiratory Distress Syndrome

This article sheds light on some features of ghrelin (GHR)- and tryptase (Try)-positive mast cells (MCs) distribution in human lung of preterm newborns with respiratory distress syndrome (RDS). GHR possessed anti-inflammatory activity and reliable therapeutic properties in some lung diseases. So far, GHR expression has been defined predominantly in neuroendocrine cells of bronchial mucosa in fetal and infant lungs. Lung tissue from 8 dead newborns with RDS were investigated immunohistochemically with anti-GHR and anti-Try antibodies. The number of GHR+ and Try+ MCs was determined in three locations –bronchi, bronchiole and in alveolar septa. MCs were more numerous around main bronchi with diminishing numbers around bronchiole and in alveolar septa. The number of MCs in the latter was increased in newborns with pneumonia. The number of GHR+ MCs in alveolar septa was lower in newborns with RDS as compared to newborns with RDS combined with pneumonia (2.83 ± 1.13 vs 4.81 ± 2.6, p < 0.001). The amount of Try+ MCs along bronchial wall was significantly more than GHR+ MCs in RDS newborns (6.97 ± 4.53 vs 3.85 ± 4.30, p = 0.001). It could be supposed that pulmonary MCs increased in newborn lungs in inflammatory process. MCs in human lung contained GHR peptide that had immunomodulatory function and participated in hormone regulation of inflammation.

Anaphylaxis with Associated Fibrinolysis, Reversed with Tranexamic Acid and Demonstrated by Thrombelastography

In the surgical setting, fibrinolysis can be a serious complication of anaphylaxis. We present four cases of anaphylaxis that were associated with fibrinolysis during anaesthesia, and the use of the thrombelastograph to demonstrate this haemostatic defect and its correction using tranexamic acid.

Pseudoanaphylaxis

Profound hypotension and cardiac arrest after commencement of combined spinal and general anaesthesia in a patient for knee replacement surgery raised the suspicion of anaphylaxis. This seemed to be confirmed when a mast cell tryptase test taken about 90 minutes after the onset of the hypotension was elevated. However, subsequent intradermal skin testing twelve weeks later did not identify a causal drug. Repeat mast cell tryptase at the time showed the same elevation, which led to the correct diagnosis of mastocytosis and a secondary diagnosis that the patient's hypotension and cardiac arrest were the result of her spinal anaesthesia.

If the serum tryptase is elevated during the event but no allergic agent can be identified, a further serum tryptase should be taken several weeks later to exclude a persistent elevation due to mastocytosis.

Sugammadex hypersensitivity and underlying mechanisms: a randomised study of healthy non-anaesthetised volunteers

BACKGROUND

We investigated potential for hypersensitivity reactions after repeated sugammadex administration and explored the mechanism of hypersensitivity.

METHODS

In this double-blind, placebo-controlled study (NCT00988065), 448 healthy volunteers were randomised to one of three arms to receive three repeat i.v. administrations of either sugammadex 4 mg kg^-1, 16 mg kg^-1, or placebo. Primary endpoint was percentage of subjects with hypersensitivity (assessed by an independent adjudication committee). Secondary endpoint of anaphylaxis was classified per Sampson and Brighton criteria. Exploratory endpoints included skin testing, serum tryptase, anti-sugammadex antibodies [immunoglobulin (Ig) E/IgG], and other immunologic parameters.

RESULTS

Hypersensitivity was adjudicated for 1/148 (0.7%), 7/150 (4.7%), and 0/150 (0.0%) subjects after sugammadex 4 mg kg^-1, 16 mg kg^-1, and placebo, respectively. After sugammadex 16 mg kg^-1, one subject met Sampson criterion 1 and Brighton level 1 (highest certainty) anaphylaxis criteria; two met Brighton level 2 criteria. After database lock it was determined that certain protocol deviations could have introduced bias in the reporting of hypersensitivity signs/symptoms in a subject subset. Objective laboratory investigations indicated that potential underlying hypersensitivity mechanisms were unlikely to have been activated; the results suggest that most of the observed hypersensitivity reactions were unlikely IgE/IgG-mediated.

CONCLUSION

Dose-dependent hypersensitivity or anaphylaxis reactions to sugammadex were observed when administered without prior neuromuscular blocking agent. Laboratory investigations do not suggest prevalent allergen-specific IgE/IgG-mediated immunologic hypersensitivity. Because it could not be fully excluded that estimates of hypersensitivity/anaphylaxis incidence were unbiased, an additional study was conducted to characterise the potential for hypersensitivity reactions and is described in a companion report.

CLINICAL TRIAL REGISTRATION

http://www.clinicaltrials.gov NCT00988065; Protocol number P06042.

Immediate Hypersensitivity to Contrast Agents: The French 5-year CIRTACI Study

BACKGROUND

Iodinated and gadolinium-based contrast media (ICM; GBCM) induce immediate hypersensitivity (IH) reactions. Differentiating allergic from non-allergic IH is crucial; allergy contraindicates the culprit agent for life. We studied frequency of allergic IH among ICM or GBCM reactors.

METHODS

Patients were recruited in 31 hospitals between 2005 and 2009. Clinical symptoms, plasma histamine and tryptase concentrations and skin tests were recorded. Allergic IH was diagnosed by intradermal tests (IDT) with the culprit CM diluted 1:10, "potentially allergic" IH by positive IDT with pure CM, and non-allergic IH by negative IDT.

FINDINGS

Among 245 skin-tested patients (ICM = 209; GBCM = 36), allergic IH to ICM was identified in 41 (19.6%) and to GBCM in 10 (27.8%). Skin cross-reactivity was observed in 11 patients with ICM (26.8%) and 5 with GBCM (50%). Allergy frequency increased with clinical severity and histamine and tryptase concentrations (p < 0.0001). Cardiovascular signs were strongly associated with allergy. Non-allergic IH was observed in 152 patients (62%) (ICM:134; GBCM:18). Severity grade was lower (p < 0.0001) and reaction delay longer (11.6 vs 5.6 min; p < 0.001). Potentially allergic IH was diagnosed in 42 patients (17.1%) (ICM:34; GBCM:8). The delay, severity grade, and mediator release were intermediate between the two other groups.

INTERPRETATION

Allergic IH accounted for < 10% of cutaneous reactions, and > 50% of life-threatening ones. GBCM and ICM triggered comparable IH reactions in frequency and severity. Cross-reactivity was frequent, especially for GBCM. We propose considering skin testing with pure contrast agent, as it is more sensitive than the usual 1:10 dilution criteria.

In Vivo Cysteinyl Leukotriene Release in Allergic and Nonallergic Immediate Hypersensitivity Reactions during Anesthesia

BACKGROUND

Immediate hypersensitivity reactions occurring during anesthesia are classified as allergic when skin tests and mast cell tryptase are positive and as nonallergic when negative results are obtained. Cysteinyl leukotrienes (cysLTs) are potent mediators synthesized by mast cell and eosinophil that induce bronchial constriction. They could play a role in hypersensitivity reactions.

METHODS

cysLT C4, D4, and E4 concentrations were measured by a competition immunoassay in serial plasma samples obtained prospectively from 21 anesthetized controls and retrospectively from 34 patients who reacted at induction of anesthesia (24 with allergic and 10 with nonallergic reactions).

RESULTS

In controls, the median (interquartile range) cysLT concentration was 0.83 (0.69 to 1.02) μg/l before anesthesia and was unchanged 30 min, 6 h, and 24 h afterward. In the patients with allergic reactions, the values were highly increased 30 to 60 min after the reaction (17.9 [7.8 to 36.0] μg/l), while the patients with nonallergic reactions had less increased values (7.3 [3.0 to 11.5] μg/l). The difference between the three groups was significant (P < 0.0001). Increased values persisted during the 24 h of observation. Concentrations were significantly higher in patients with bronchospasm (P = 0.016).

CONCLUSIONS

cysLTs appear to be an important mediator of allergic and nonallergic immediate hypersensitivity reactions. These findings might open a new field for management of patients with hypersensitivity reactions, especially nonallergic ones.

Xylometazoline nasal drops induced anaphylaxis: An atypical perioperative complication

Xylometazoline nasal drops used for nasal decongestion can have side-effect in the form of palpitation, hypertension, headache, and tremors. Anaphylaxis to xylometazoline nasal drops is a relatively unrecognized complication. We encountered a patient posted for tonsillectomy who developed serious anaphylaxis upon administration of a commercially available preparation of xylometazoline nasal drops and required aggressive management for stabilization. Further evaluation and literature search indicated toward the preservative (benzylalkonium chloride) as the cause of this adverse event.

Mechanisms of anaphylaxis in human low-affinity IgG receptor locus knock-in mice

BACKGROUND

Anaphylaxis can proceed through distinct IgE- or IgG-dependent pathways, which have been investigated in various mouse models. We developed a novel mouse strain in which the human low-affinity IgG receptor locus, comprising both activating (hFcγRIIA, hFcγRIIIA, and hFcγRIIIB) and inhibitory (hFcγRIIB) hFcγR genes, has been inserted into the equivalent murine locus, corresponding to a locus swap.

OBJECTIVE

We sought to determine the capabilities of hFcγRs to induce systemic anaphylaxis and identify the cell types and mediators involved.

METHODS

hFcγR expression on mouse and human cells was compared to validate the model. Passive systemic anaphylaxis was induced by injection of heat-aggregated human intravenous immunoglobulin and active systemic anaphylaxis after immunization and challenge. Anaphylaxis severity was evaluated based on hypothermia and mortality. The contribution of receptors, mediators, or cell types was assessed based on receptor blockade or depletion.

RESULTS

The human-to-mouse low-affinity FcγR locus swap engendered hFcγRIIA/IIB/IIIA/IIIB expression in mice comparable with that seen in human subjects. Knock-in mice were susceptible to passive and active anaphylaxis, accompanied by downregulation of both activating and inhibitory hFcγR expression on specific myeloid cells. The contribution of hFcγRIIA was predominant. Depletion of neutrophils protected against hypothermia and mortality. Basophils contributed to a lesser extent. Anaphylaxis was inhibited by platelet-activating factor receptor or histamine receptor 1 blockade.

CONCLUSION

Low-affinity FcγR locus-switched mice represent an unprecedented model of cognate hFcγR expression. Importantly, IgG-related anaphylaxis proceeds within a native context of activating and inhibitory hFcγRs, indicating that, despite robust hFcγRIIB expression, activating signals can dominate to initiate a severe anaphylactic reaction.

Diagnostic value of histamine and tryptase concentrations in severe anaphylaxis with shock or cardiac arrest during anesthesia

BACKGROUND

The diagnosis of acute life-threatening allergic reactions during anesthesia relies on clinical signs, histamine and/or tryptase measurements, and allergic testing. In patients who die after the reaction, skin tests cannot be performed, and the effect of resuscitation manoeuvres on mediator concentrations is unknown. The authors compared plasma histamine and tryptase concentrations in patients with severe allergic reactions during anesthesia with those measured in patients with shock due to other causes.

METHODS

Patients with life-threatening allergic reactions were retrieved from a previous database (Group ALLERGY). All had positive allergy tests to administered agents. Patients with severe septic/cardiogenic shock or cardiac arrest (Group CONTROL) had histamine and tryptase measurements during resuscitation manoeuvres. Receiver operating characteristics curves were built to calculate the optimal mediator thresholds differentiating allergic reactions from others.

RESULTS

One hundred patients were included, 75 in Group ALLERGY (cardiovascular collapse, 67; cardiac arrest, 8) and 25 in Group CONTROL (shock, 11; cardiac arrest, 14). Mean histamine and tryptase concentrations remained unchanged throughout resuscitation in Group CONTROL and were significantly higher in Group ALLERGY. The optimal thresholds indicating an allergic mechanism were determined as 6.35 nmol/l for histamine (sensitivity: 90.7% [95% CI, 81.7 to 96.1]; specificity: 91.7% [73.0 to 98.9]) and 7.35 μg/l for tryptase (sensitivity: 92% [83.4 to 97.0]; specificity: 92% [73.9 to 99.0]).

CONCLUSIONS

Resuscitation manoeuvres by themselves did not modify mediator concentrations. Virtually all life-threatening reactions during anesthesia associated with mediator concentrations exceeding the thresholds were allergic events. These findings have potential forensic interest when a patient dies during anesthesia.

Perioperative anaphylaxis

Perioperative anaphylaxis is a life-threatening condition with an estimated prevalence of 1:3,500 to 1:20,000 procedures and a mortality rate of up to 9 %. Clinical presentation involves signs such as skin rash, urticaria, angioedema, bronchospasm, tachycardia, bradycardia, and hypotension. Prompt recognition and treatment is of utmost importance to the patient's prognosis, since clinical deterioration can develop rapidly. Epinephrine is the main treatment drug, and its use should not be postponed, since delayed administration is associated with increased mortality. Elevated levels of serum tryptase help to confirm the diagnosis. The main agents involved in IgE-mediated perioperative anaphylaxis are neuromuscular blocking agents, latex, antibiotics, hypnotics, opioids, and colloids. Specific investigation should be conducted 4 to 6 weeks after the reaction and relies on skin tests, serum-specific IgE, and challenge procedures. This review aims to discuss the main aspects of perioperative anaphylaxis: risk factors, diagnosis, treatment, culprit agents, specific investigation, and preventive measures.

Severity of cutaneous findings predict the presence of systemic symptoms in pediatric maculopapular cutaneous mastocytosis

Although the prognosis of maculopapular cutaneous mastocytosis (MPCM), also referred to as urticaria pigmentosa, is often benign, clinicians lack evidence to reliably predict those at risk of associated systemic manifestations. We sought to elucidate clinical markers of disease severity to provide better treatment and prognostic information for individuals with MPCM. A retrospective chart review querying characteristics of children diagnosed with MPCM in the Emory Dermatology Clinic was performed. Follow-up was obtained through a clinical encounter or telephone interview. Linear regression was used to determine predictors of the number of MPCM-related systemic symptoms. Of 67 subjects, 57% were male, and the mean age of onset was 4.5 months. The maximum number of MPCM lesions was 1 to 10 in 16%, 11 to 30 in 33%, 31 to 50 in 25%, 51 to 100 in 6%, and more than 100 in 20% of subjects. For their MPCM lesions, 46% of subjects reported itching, 34% flushing, and 25% blistering. Reported systemic symptoms included diarrhea (22%), abdominal pain (15%), wheezing or dyspnea (13%), vomiting (10%), bone pain (10%), headaches (8%), cough (10%), rhinorrhea (8%), irritability (6%), and anaphylaxis (1.5%). In a multivariate linear regression analysis, the maximum number of MPCM lesions (p = 0.02) and the number of skin symptoms (p < 0.01) were statistically significant predictors of the number of systemic symptoms, controlling for age of onset, body sites involved, and sex. The correlation between cutaneous findings and symptomatology could aid clinicians in identifying individuals with MPCM who might warrant systemic evaluation and therapy.

Hypersensitivity reactions to non beta-lactam antimicrobial agents, a statement of the WAO special committee on drug allergy

Antibiotics are used extensively in the treatment of various infections. Consequently, they can be considered among the most important agents involved in adverse reactions to drugs, including both allergic and non-allergic drug hypersensitivity [J Allergy Clin Immunol 113:832–836, 2004]. Most studies published to date deal mainly with reactions to the beta-lactam group, and information on hypersensitivity to each of the other antimicrobial agents is scarce. The present document has been produced by the Special Committee on Drug Allergy of the World Allergy Organization to present the most relevant information on the incidence, clinical manifestations, diagnosis, possible mechanisms, and management of hypersensitivity reactions to non beta-lactam antimicrobials for use by practitioners worldwide.

Circulatory collapse after topical application of vancomycin powder during spine surgery

A hypersensitivity reaction, either anaphylactic or anaphylactoid, is a well-known adverse effect following intravenous and oral administration of vancomycin. The authors report a case of circulatory collapse and its management after the topical application of vancomycin powder during spinal instrumentation surgery. A 52-year-old woman with breast cancer and metastasis to her spine underwent a vertebrectomy of the T-10 vertebra with instrumented reconstruction from T-8 to T-12. The patient was hemodynamically stable during most of the procedure despite a 2-L blood loss requiring administration of crystalloids, colloids, packed red blood cells, and fresh-frozen plasma. During closure of the subcutaneous layer, there was a sudden drop in blood pressure from 120/60 to 30/15 mm Hg and an increase in heart rate from 95 to 105 bpm. No skin erythema or rash was visible, and there was no bronchospasm or increase in airway pressure. The patient was treated with fluids, boluses of ephedrine, phenylephrine, and adrenaline. The operation was completed and the patient woke up neurologically intact but did require blood pressure support with a norepinephrine infusion for the next 4 hours. She was discharged from hospital in a good clinical state on the 4th postoperative day. It was speculated that the rapid absorption of vancomycin powder applied on the surgical wound caused an anaphylactoid reaction and the circulatory collapse. With an increase in the use of topical vancomycin in surgical wounds, communication and awareness among all intraoperative team members is important for rapid diagnosis of an adverse reaction and for appropriate management.

Systemic mastocytosis presenting as intraoperative anaphylaxis with atypical features: a report of two cases

Two cases of perioperative cardiovascular collapse are presented that were associated with markedly elevated mast cell tryptase levels shortly after the event, leading to the assumption that an immunoglobin E-mediated, drug-induced anaphylaxis had occurred. However, the clinical picture in both cases was atypical and subsequent skin testing failed to identify a triggering drug. Further blood tests, some weeks later, revealed persistently elevated baseline levels of mast cell tryptase. In both cases bone marrow biopsy and genetic testing confirmed the diagnosis of mastocytosis. We present evidence and speculate that mast cell degranulation was triggered by tourniquet release in the first case and by exposure to peanuts in the second. An atypical presentation of anaphylaxis should alert the anaesthetist to the possibility of previously undiagnosed mastocytosis.

Severe anaphylactoid reaction to thymoglobulin in a pediatric renal transplant recipient

Intraoperative administration of thymoglobulin is an integral part of the anti-rejection regimen during organ transplantation. However, its administration may be associated with complications. An anaphylactoid reaction that occurred in a pediatric recipient of a living-related renal transplant, on initiating an intravenous infusion of thymoglobulin, is presented.

Anaphylaxis related to fentanyl citrate

Anaphylaxis is a fulminant, unexpected, immunoglobulin E-mediated allergic reaction that can be triggered by multiple agents. Common causative agents include neuromuscular blocking drugs, latex, antibiotics, colloids, hypnotics, and opioids. Fentanyl citrate, however, is an extremely unusual cause of anaphylaxis. Pulmonary edema, although uncommon in anaphylaxis, can be a prominent feature, as was in one of the patient. An adverse drug reaction is a noxious or unintended reaction to a drug that is administered in standard doses by the proper route for the purpose of prophylaxis, diagnosis, or treatment. Reactions are classified into two major subtypes: type A, which are dose dependent and predictable; and type B, which are not dose dependent and unpredictable. Unpredictable reactions include immune (allergic) or no immune drug hypersensitivity reactions and are related to genetic susceptibilities or undefined mechanisms (formally called idiosyncratic and intolerance reactions). A drug allergy is always associated with an immune mechanism for which evidence of drug-specific antibodies or activated T lymphocytes can be shown. In the last few years, many novel drugs have entered clinical practice (i.e., biologic agents) generating novel patterns of drug hypersensitivity reactions. As old drugs continue to be used, new clinical and biologic techniques enable improvement in the diagnosis of these reactions.

Effects of sugammadex and rocuronium mast cell number and degranulation in rat liver

We investigated the effect of rocuronium- and sugammadex-induced mast cell increase and degranulation in rat portal triads. Forty-two rats, in six groups, received either rocuronium 1 mg.kg(-1); sugammadex 15 mg.kg(-1); sugammadex 100 mg.kg(-1); rocuronium 1 mg.kg(-1) and 5 min later, sugammadex 15 mg.kg(-1); rocuronium 1 mg.kg(-1) and 5 min later, sugammadex 100 mg.kg(-1); or isotonic saline. Total mast cell numbers were significantly higher with rocuronium only, than in all other groups (p<0.003), although in all active groups, the number was greater than the control. Total mast cell number was significantly higher with rocuronium and low-dose sugammadex compared with low-dose sugammadex only. The number of tryptase-positive mast cells with rocuronium only was significantly higher than in all other groups (p<0.003). Tryptase-positive mast cell numbers in both groups receiving both rocuronium and sugammadex were significantly higher compared with both groups receiving sugammadex only. Rocuronium increased mast cell numbers, and degranulation was mitigated by sugammadex. These results suggest that sugammadex may be beneficial in treatment of rocuronium-induced anaphylaxis.

Histamine-releasing and allergenic properties of opioid analgesic drugs: resolving the two

Opioid analgesics are amongst the most commonly administered drugs in hospitals. Whether natural or synthetic, they show some common structural features, morphine-like pharmacological action and binding specificity for complementary opioid receptors. Tramadol differs from the other opioid analgesics in possessing monoaminergic activity in addition to its affinity for the µ opioid receptor. Many opioids are potent histamine releasers producing a variety of haemodynamic changes and anaphylactoid reactions, but the relationship of the appearance of these effects to the histamine plasma concentration is complex and there is no direct and invariable relationship between the two. Studies of the histamine-releasing effects, chiefly centred on morphine, reveal variable findings and conclusions often due to a range of factors including differences in technical measurements, dose, mode of administration, site of injection, the anatomical distribution of histamine receptors and heterogeneity of patient responses. Morphine itself has multiple direct effects on the vasculature and other haemodynamically-active mediators released along with histamine contribute to the variable responses to opioid drug administration. Despite their heavy use and occasional apparent anaphylactic-like side-effects, immunoglobulin E antibody-mediated immediate hypersensitivity reactions to the drugs are not often encountered. Uncertainties associated with skin testing with these known histamine-releasers, and the general unavailability of opioid drug-specific immunoglobulin E antibody tests contribute to the frequent failure to adequately investigate and establish underlying mechanisms of reactions by distinguishing anaphylactoid from true anaphylactic reactions. Clinical implications for diagnosis of reactions and some speculations on the rarity of true Type 1 allergies to these drugs are presented.

Diagnosis and treatment of cutaneous mastocytosis in children: practical recommendations

Cutaneous mastocytosis in children is a generally benign disease that can present at birth and is often associated with mast cell mediator-related symptoms including pruritus, flushing, and abdominal pain with diarrhea. The most common form of presentation is urticaria pigmentosa, also referred to as maculopapular mastocytosis. Flares of lesions are induced by triggers such as physical stimuli, changes in temperature, anxiety, medications, and exercise. The skin lesions are typically present on the extremities. Symptoms respond to topical and systemic anti-mediator therapy including antihistamines and cromolyn sodium. Remission at puberty is seen in a majority of cases. Progression to systemic mastocytosis with involvement of extracutaneous organs is not common. The cause of cutaneous mastocytosis is unknown and familial cases are rare. Mutations of c-kit have been observed in the skin of those affected. The diagnosis is established on clinical grounds and the findings on skin biopsy. Bone marrow studies are recommended if there is suspicion of progression of disease to an adult form, if cytoreductive therapy is contemplated, or if skin lesions remain present and/or tryptase levels remain elevated after puberty. The use of chemotherapy, including kinase inhibitors, is strongly discouraged unless severe hematologic disease is present, since malignant evolution is extremely rare.

Drug-specific cyclodextrins with emphasis on sugammadex, the neuromuscular blocker rocuronium and perioperative anaphylaxis: implications for drug allergy

Cyclodextrins, oligosaccharides linked in a circular arrangement around a central cavity, are used extensively in the pharmaceutical industry to improve drug delivery. Their usefulness depends on their capacity to form a drug inclusion, or host-guest, complex within the cavity. In an attempt to improve the delivery of the widely used neuromuscular blocking drug (NMBD) rocuronium, a rocuronium inclusion complex was formed with a chemically modified γ-cyclodextrin. The high binding affinity and specificity of the modified carrier (named sugammadex) for rocuronium (and other aminosteroid NMBDs) led to its use in anaesthesia as an innovative and useful agent for rapid reversal of rocuronium-induced neuromuscular block by sequestering the drug as an inclusion complex. This, in turn, led to the suggestion that sugammadex might be useful to remove the NMBD from the circulation of patients experiencing rocuronium-induced anaphylaxis, a suggestion subsequently supported in case reports where traditional treatment had failed. Successful resuscitations suggested that sugammadex might be a valuable new treatment for such intractable cases but, given the inappropriateness of clinical trials, confirmation or refutation will have to await the slow accumulation of results of individual case reports. Important questions related to antibody accessibility of drug allergenic structures on the rocuronium-sugammadex inclusion complex, and the competition between sugammadex and IgE antibodies (both free and cell bound) for rocuronium, also remain and can be investigated in vitro. The sugammadex findings indicate that the use of carrier molecules such as the cyclodextrins to improve drug delivery will sometimes give rise to changed immunologic and allergenic behaviour of some drugs and this will have to be taken into account in preclinical drug safety assessments of drug-carrier complexes. The possibility of encapsulating and removing other allergenic drugs, e.g., penicillins and cephalosporins, in cases of difficult-to-reverse anaphylaxis to these drugs is discussed.

Anaphylaxis and other Adverse Reactions to Blue Dyes: A Case Series

We report three cases of anaphylaxis during anaesthesia confirmed on intradermal testing to be related to patent blue V dye (Guerbet – Chemical Abstract Service 3536-49-0). All three cases were associated with moderate to severe hypotension. Two cases had delayed onset, and two were associated with a rash. None of the cases were associated with bronchospasm. In all three patients the interference with pulse oximetry readings contributed to difficulties in management. We recommend the use of a test dose of blue dye prior to surgery, as suggested in the manufacturer's product information. We also recommend high vigilance for possible allergic reactions when patent blue dyes are used for sentinel lymph node mapping, because the presentations may be atypical and the reduced pulse oximetry readings may be a distraction.

Follow-up after anaesthetic anaphylaxis

background: the anaesthetic allergy clinic has been established at our institution for 30 years. Our practice has been to give patients a letter detailing the results of their investigations to pass on to subsequent anaesthetists. Our aims were to assess the adequacy of this letter in ensuring this vital communication, and to quantify the effectiveness of our recommendations on the safety of future anaesthesia.

METHODS

a project was undertaken to contact 606 previous clinic patients living in New South Wales by using last known addresses on our database, public telephone listing and local doctors. The review also involved collecting information, where available, about subsequent anaesthesia and the adequacy of information transfer about medications given safely or otherwise at this time.

RESULTS

of 606 patients, 246 were contactable. Of these, 183 had been anaesthetised subsequently, all safely. It was found that in only 11 cases had the patient's clinic letter been updated with the information from subsequent anaesthesia. We updated the letters of 82 patients with new information to improve the safety of drug selection for future anaesthesia.

CONCLUSIONS

although clinic testing allowed a high degree of safety in subsequent anaesthesia, it is evident that there is a need for systems to be implemented to improve the flow of patient anaesthetic allergy information after subsequent anaesthesia.

Perioperative anaphylaxis

The incidence of immune-mediated anaphylaxis during anesthesia ranges from 1 in 10,000 to 1 in 20,000. Neuromuscular blocking agents are most frequently incriminated, followed by latex and antibiotics, although any drug or substance used may be a culprit. Diagnosis relies on tryptase measurements at the time of the reaction and skin tests, specific immunoglobulin E, or basophil activation assays. Treatment consists of rapid volume expansion and epinephrine administration titrated to symptom severity.

[Anaphylaxis during anaesthesia]

BACKGROUND

Anaphylaxis is a serious life-threatening generalized or systemic hypersensitivity reaction. The aim of this paper is to provide knowledge on how to diagnose, treat and follow up patients with suspected anaphylaxis during general and local anaesthesia.

MATERIAL AND METHODS

The article is based on literature identified through a non-systematic search in PubMed, the Scandinavian Guidelines on anaphylaxis during anaesthesia and on own research.

RESULTS

Anaphylactic symptoms during anaesthesia vary with respect to severity. Manifestations from skin and the cardiovascular and respiratory systems are present simultaneously in approximately 70 % of patients. Early treatment with adrenaline, fluid and extra oxygen may be vital for survival without sequelae. The following patients should be assessed before anaesthesia: those with moderate or serious reactions or with reactions that raise suspicion of allergy which may cause problems in connection with future treatment. Neuromuscular blocking agents are the main cause of IgE-mediated anaphylaxis during anaesthesia in Norway. New research has shown that allergy towards neuromuscular blocking agents can develop after ingestion of cough syrup containing pholcodine (stimulates asymptomatic production of antibodies). These antibodies cause cross-sensibilisation with neuromuscular blocking agents. The cough syrup Tuxi was withdrawn from the Norwegian market during spring 2007.

INTERPRETATION

Allergic reactions during anaesthesia are rare and potentially life-threatening; patients should be followed up and treated in a standardized way.

Suspected recurrent anaphylaxis in different forms during general anesthesia

We report on a patient who presented with recurrent severe shock during general anesthesia. The patient was a man scheduled for lung surgery whose first attack was a coronary spasm, which was followed by a second shock with severe bronchospasm and hypotension 4 weeks later. An elevated serum tryptase concentration was observed, and subsequent skin testing revealed negative reactions to some drugs administered in this case. This case serves to alert anesthetists to the possibility of some different forms of allergy and highlights the importance of rigorous investigation of all the reagents and phenomena.

The investigation of bronchospasm during induction of anaesthesia

BACKGROUND

The aim of this study was to ascertain whether anaesthetic induction-related anaphylactic bronchospasm could be distinguished from other types of bronchospasm by clinical features and response to treatment. Such features could then be used to identify a group of patients in whom skin testing is indicated.

METHODS

We retrospectively studied data from 183 patients referred to an anaesthetic allergy clinic because of bronchospasm during induction. For the analysis, the patients were divided into two groups depending on whether there was evidence suggesting immunological anaphylaxis.

RESULTS

When the patients in whom intradermal tests were positive were compared with those in whom intradermal tests were negative, the skin test-positive patients had significantly more severe reactions, and they were more commonly associated with other clinical signs. Mast cell tryptase (MCT) was an excellent discriminator between reactions likely to be allergic and those unlikely to be allergic.

CONCLUSIONS

Anaphylactic bronchospasm related to induction of anaesthesia is more likely to be severe than bronchospasm due to non-immune causes. An allergic cause is more likely if there are associated features of anaphylaxis (skin changes, hypotension, angioedema) or elevated MCT. Patients with any of these features should undergo immuno-allergolical investigation.

General anesthetic allergy testing

Anaphylaxis in the setting of general anesthesia is a rare but potentially lethal event. The investigation of severe reactions is important for confirming the clinical diagnosis and identifying likely causative agents and safe agents that may be used in the future. Many comprehensive reports have described the testing protocol of individual specialized units, whereas there has been no standardization of testing techniques or formal assessment of these tests' diagnostic accuracy. We review the literature with reference to the recently published standards for reporting of diagnostic accuracy (STARD) and make recommendations for future studies of diagnostic accuracy in the field.