Role of mast cells, basophils and their mediators in adverse reactions to general anesthetics and radiocontrast media

Mast cell conditions and drug allergy: when to suspect and how to manage

PURPOSE OF REVIEW

Patients with mast cell disorders frequently experience symptoms from excessive mediator release like histamine and tryptase, ranging from mild flushing to severe anaphylactic responses. Hypersensitivity reactions (HRs) to drugs are a major cause of anaphylaxis in these patients, who often worry about triggering mast cell degranulation when taking medications. The aim of this review is to explore the complex interactions between mast cell disorders and drug HRs, focusing on the clinical challenges of managing these conditions effectively to enhance understanding and guide safer clinical practices.

RECENT FINDINGS

Among the drugs most commonly associated with hypersensitivity reactions in patients with mast cell disorders are non-steroidal anti-inflammatory drugs, antibiotics, and perioperative agents. Recent studies have highlighted the role of Mas-related G-protein coupled receptor member X2 (MRGPRX2) - a receptor involved in non-immunoglobulin E mediated mast cell degranulation - in exacerbating HRs. Investigations reveal varied drug tolerance among patients, underscoring the need for individual risk assessments.

SUMMARY

Tailored diagnostic approaches are crucial for confirming drug allergies and assessing tolerance in patients with mastocytosis, preventing unnecessary medication avoidance and ensuring safety before acute situations arise.

Case Report: Isosulfan Blue-Related Anaphylaxis

Anaphylaxis is an acute multisystem syndrome typically resulting from the sudden release of mast cell and basophil-derived mediators into the circulatory system. Isosulfan blue dye is a rare, but known, mediator of anaphylaxis with an incidence between 0.16% and 2% of cases. We report two cases of anaphylaxis attributed to the use of isosulfan blue dye in the intraoperative setting. Both of the patients we report had grade 3 anaphylactic reactions requiring vasopressors to correct significant hypotension. Both patients required overnight monitoring in the intensive care unit with the second patient also requiring continued vasopressor support.

Effect of brimonidine tartrate on basophil activation in glaucoma patients

AIM

To evaluate the mechanism of which brimonidine tartrate 0.15% causes clinical hypersensitivity.

METHODS

A prospective case-control study comparing 8 glaucoma patients with clinical hypersensitivity to brimonidine to a control group consisting 13 healthy volunteers. Blood samples were stimulated with brimonidine 0.15%, timolol 0.5% or brimonidine tartrate/timolol maleate 0.2%/0.5%. Premixed antibodies (CD63/FITC and aIgE/PE) were added for direct staining and whole-blood samples were lysed, fixed and analyzed by a flow cytometer. The basophil population was defined by high IgE cell expression. Degranulation was identified by the expression of the activation molecule CD63.

RESULTS

Basophil activation was not significant when comparing percent of activated basophils of patients and healthy controls after exposure to brimonidine (2.58%, 2.45%, respectively, P=0.72). There was a significant suppression of basophil activation when a combination of brimonidine-timolol (0.87%) was compared to timolol (2.27%; P=0.012) and to brimonidine alone (2.58%; P=0.017).

CONCLUSION

The results of our study do not support the hypothesis that brimonidine induces an immediate allergic reaction. Basophil activation was suppressed by the presence of β-blockers in patients hypersensitive to brimonidine and in healthy individuals. This finding indicates that timolol suppress brimonidine drug reaction by a different mechanism.

The Role of KIT Mutations in Anaphylaxis

PURPOSE OF REVIEW

Gain of function KIT mutations are detected in clonal mast cell diseases, namely mastocytosis and monoclonal mast cell activation syndrome. Timely diagnosis and treatment of these disorders are crucial because of their association with severe and life-threatening anaphylaxis. KIT mutations also have implications for targeted therapies of mast cell disorders. This review article strives to serve as an overview of the role of clonal mast cell disorders in anaphylaxis while elucidating current and future therapies.

RECENT FINDINGS

Clonal mast cell disease has been increasingly diagnosed in patients with severe hymenoptera allergy and those with recurrent unexplained anaphylaxis. The current state of knowledge of the epidemiology, pathophysiology, diagnosis, and treatment of mastocytosis with a particular focus on anaphylaxis and its triggers which are described in this context. Novel and forthcoming treatments are discussed including the relevance of KIT mutation status. This review provides an overview of the role of KIT mutations in mastocytosis and anaphylaxis, and highlights emerging therapies for mastocytosis, targeting these mutations.

Vancomycin-induced red man syndrome presentation in a preterm infant

A male infant born at 32 weeks' gestation with a birthweight of 1030 g was started on intravenous vancomycin for a femoral osteomyelitis. On day 7 of treatment, he developed an erythematous flushed rash, rapidly spreading from the head to trunk and extremities, and became markedly irritable; vancomycin infusion was promptly stopped, with subsequent skin clearance. Given the wide use of vancomycin for the treatment of neonatal infections, a good awareness of red man syndrome signs and symptoms in the neonatal population is fundamental to recognize this adverse drug reaction and manage its rare but possible life-threatening complications.

The clinical utility of basophil activation testing in diagnosis and monitoring of allergic disease

The basophil activation test (BAT) has become a pervasive test for allergic response through the development of flow cytometry, discovery of activation markers such as CD63 and unique markers identifying basophil granulocytes. Basophil activation test measures basophil response to allergen cross-linking IgE on between 150 and 2000 basophil granulocytes in <0.1 ml fresh blood. Dichotomous activation is assessed as the fraction of reacting basophils. In addition to clinical history, skin prick test, and specific IgE determination, BAT can be a part of the diagnostic evaluation of patients with food-, insect venom-, and drug allergy and chronic urticaria. It may be helpful in determining the clinically relevant allergen. Basophil sensitivity may be used to monitor patients on allergen immunotherapy, anti-IgE treatment or in the natural resolution of allergy. Basophil activation test may use fewer resources and be more reproducible than challenge testing. As it is less stressful for the patient and avoids severe allergic reactions, BAT ought to precede challenge testing. An important next step is to standardize BAT and make it available in diagnostic laboratories. The nature of basophil activation as an ex vivo challenge makes it a multifaceted and promising tool for the allergist. In this EAACI task force position paper, we provide an overview of the practical and technical details as well as the clinical utility of BAT in diagnosis and management of allergic diseases.

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.

New method of screening allergenic components from Shuanghuanglian injection: with RBL-2H3/CMC model online HPLC/MS system

Shuanghuanglian (SHL) injection is a traditional Chinese medicine (TCM) injection widely used in China to treat influenza, tonsillitis, bronchitis, and faucitis. Adverse drug reactions (ADR) of SHL injection, majorly manifested as allergic reactions, were among the leading causes of death from TCM injection. In this study, an RBL-2H3/CMC online LC/MS system was established to screen and identify allergenic components in SHL injection, by which Baicalin was identified as a potential allergenic component. Allergenic activities of baicalin were investigated in RBL-2H3 cell degranulation and β-hexosaminidase release tests in vitro. Our results showed that baicalin dose-dependently induced RBL-2H3 cell degranulation and β-hexosaminidase release in the range of 0-50μg/ml. The RBL-2H3/CMC online LC/MS system developed in this study may potentially be used to screen allergenic components in other TCM injections.

Use of imaging agent to determine postoperative indwelling epidural catheter position

Background

Epidural anesthesia is widely used to provide pain relief, whether for surgical anesthesia, postoperative analgesia, treatment of chronic pain, or to facilitate painless childbirth. In many cases, however, the epidural catheter is inserted blindly and the indwelling catheter position is almost always uncertain.

Methods

In this study, the loss-of-resistance technique was used and an imaging agent was injected through the indwelling epidural anesthesia catheter to confirm the position of its tip and examine the migration rate. Study subjects were patients scheduled to undergo surgery using general anesthesia combined with epidural anesthesia. Placement of the epidural catheter was confirmed postoperatively by injection of an imaging agent and X-ray imaging.

Results

The indwelling epidural catheter was placed between upper thoracic vertebrae (n = 83; incorrect placement, n = 5), lower thoracic vertebrae (n = 123; incorrect placement, n = 5), and lower thoracic vertebra-lumbar vertebra (n = 46; incorrect placement, n = 7). In this study, a relatively high frequency of incorrectly placed epidural catheters using the loss-of-resistance technique was observed, and it was found that incorrect catheter placement resulted in inadequate analgesia during surgery.

Conclusions

Although the loss-of-resistance technique is easy and convenient as a method for epidural catheter placement, it frequently results in inadequate placement of epidural catheters. Care should be taken when performing this procedure.

[Immediate and delayed hypersensitivity reactions to iodinated radiographic contrast agents: an update]

Diagnostic and interventional radiology of patients is nowadays crucial with increasing requirement for iodinated contrast agents infusion. Besides adverse reactions after administration of the iodinated contrast agents due to their toxicity, immediate hypersensitivity reactions and reactions resembling delayed hypersensitivity appearing from 1 hour to several days later, have been reported. Patients at high risk to develop such adverse events have to be detected on the basis of their risk factors in order to prevent or limit serious outcomes. Previous reactions to contrast media, asthma, atopy and cardiovascular disorders are risk factors for anaphylactic or anaphylactoid reactions. Female gender, age and beta-blockers increase the severity. This article aims to summarize the risk of allergic reactions related to the use of iodinated contrast agents and to suggest a way for diagnosis, treatment and prevention according to each clinical situation.

Control of asthma for reducing the risk of bronchospasm in asthmatics undergoing general anesthesia and/or intravascular administration of radiographic contrast media

BACKGROUND

It is well known that patients suffering from bronchial asthma undergoing surgical procedures requiring general anesthesia (GA) or the administration of water soluble radiographic contrast media (RCM) have an increased risk of potentially severe bronchospasm. Nevertheless, little attention has been devoted to the possible preventive measures to reduce the occurrence of this potentially life-threatening event. It has been shown that the most important risk factor for bronchospasm during GA induction and/or the use of RCM is represented by a high degree of bronchial hyperreactivity with airway instability not adequately controlled by long-term anti-inflammatory treatment.

AIMS

The aim of this commentary is to underline the need for an accurate clinical and functional evaluation of asthmatics undergoing surgical procedures requiring GA or radiological procedures requiring the administration of RCM, as well as to suggest a stepwise preventive pharmacological approach for reducing the risk of bronchospasm.

METHODS

The authors' suggestions represent clinical experience of the respiratory section of an internal hospital-based working group whose aim is the prevention of asthmatic/anaphylactic/anaphylactoid reactions during the administration of anesthetics and/or RCM. The MEDLINE database was searched with a combination of keywords: general anesthesia, radio contrast media [and] bronchial asthma. The main limitation of this commentary is the scarcity of available literature on this topic.

FINDINGS

The authors suggest a therapeutic approach before surgical procedures requiring GA and/or RCM administration based on the degree of asthma control as assessed by clinical/functional criteria. In this setting, in addition to the necessity of obtaining the best control of airway reactivity, the authors suggest that an optimal control of asthma symptoms in 'real life' conditions might likely constitute a safety issue in asthmatic patients in the case of emergency procedures.

Adverse drug reactions in patients with phaeochromocytoma: incidence, prevention and management

The dangers of phaeochromocytomas are mainly due to the capability of these neuroendocrine tumours to secrete large quantities of vasoactive catecholamines, thereby increasing blood pressure and causing other related adverse events or complications. Phaeochromocytomas are often missed, sometimes only becoming apparent during therapeutic interventions that provoke release or interfere with the disposition of catecholamines produced by the tumours. Because phaeochromocytomas are rare, evidence contraindicating use of specific drugs is largely anecdotal or based on case reports. The heterogeneous nature of the tumours also makes adverse reactions highly variable among patients. Some drugs, such as dopamine D(2) receptor antagonists (e.g. metoclopramide, veralipride) and beta-adrenergic receptor antagonists (beta-blockers) clearly carry high potential for adverse reactions, while others such as tricyclic antidepressants seem more inconsistent in producing complications. Other drugs capable of causing adverse reactions include monoamine oxidase inhibitors, sympathomimetics (e.g. ephedrine) and certain peptide and corticosteroid hormones (e.g. corticotropin, glucagon and glucocorticoids). Risks associated with contraindicated medications are easily minimised by adoption of appropriate safeguards (e.g. adrenoceptor blockade). Without such precautions, the state of cardiovascular vulnerability makes some drugs and manipulations employed during surgical anaesthesia particularly dangerous. Problems arise most often when drugs or therapeutic procedures are employed in patients in whom the tumour is not suspected. In such cases, it is extremely important for the clinician to recognise the possibility of an underlying catecholamine-producing tumour and to take the most appropriate steps to manage and treat adverse events and clinical complications.

Peri-anesthetic Anaphylaxis

General anesthesia and anaphylaxis cause profound physiologic changes. When both occur simultaneously, it is often difficult to recognize and identify the medication or product responsible for the latter. Following such an event, the proper assessment, diagnosis, and recommendations are essential to prevent future reactions. This article reviews the more common causes of anaphylaxis during anesthesia.

Anaphylaxis: clinical concepts and research priorities

Anaphylaxis is a severe immediate-type hypersensitivity reaction characterized by life-threatening upper airway obstruction bronchospasm and hypotension. Although many episodes are easy to diagnose by the combination of characteristic skin features with other organ effects, this is not always the case and a workable clinical definition of anaphylaxis and useful biomarkers of the condition have been elusive. A recently proposed consensus definition is ready for prospective validation. The cornerstones of management are the supine position, adrenaline and volume resuscitation. An intramuscular dose of adrenaline is generally recommended to initiate treatment. If additional adrenaline is required, then a controlled intravenous infusion might be more efficacious and safer than intravenous bolus administration. Additional bronchodilator treatment with continuous salbutamol and corticosteroids are used for severe and/or refractory bronchospasm. Aggressive volume resuscitation, selective vasopressors, atropine (for bradycardia), inotropes that bypass the beta-adrenoreceptor and bedside echocardiographic assessment should be considered for hypotension that is refractory to treatment. Management guidelines continue to be opinion- and consensus-based, with retrospective studies accounting for the vast majority of clinical research papers on the topic. The clinical spectrum of anaphylaxis including major disease subgroups requires clarification, and validated scoring systems and outcome measures are needed to enable good-quality prospective observational studies and randomized controlled trials. A systematic approach with multicentre collaboration is required to improve our understanding and management of this disease.

Current understanding of contrast media reactions and implications for clinical management

Iodinated contrast media (CM) are an integral part of modern diagnostic medicine. Although these agents are considered to be relatively safe, adverse effects in the form of allergy-like reactions occur in a significant number of exposed patients. These reactions may be divided into immediate and delayed responses. Immediate (within 1 hour of administration) anaphylactic reactions range from urticaria and angioedema to laryngeal oedema, hypotension and even death. Delayed reactions to CM occur from 1 hour to 1 week after administration and usually have mostly cutaneous manifestations. History of prior CM reactions and atopy predispose patients to CM reactions. Despite intense research into the pathogenesis of the immediate anaphylactoid responses, new evidence shows that true IgE type I hypersensitivity mediation occurs only in rare, severe cases. The aetiology appears to be multifactorial in most individuals. There is strong evidence to conclude that type IV hypersensitivity is responsible for the delayed reactions to CM. Although switching to non-ionic agents significantly reduces the incidence of immediate reactions to CM, there is little consensus regarding corticosteroid prophylaxis in high-risk individuals. Skin testing and provocative challenges also provide little security. Therefore, physicians must be better prepared to treat immediate anaphylactoid responses. Preventing delayed CM reactions is best performed with patch and delayed intradermal testing in those with a history of prior reactions, although false-negative results have been reported. Corticosteroids and antihistamines may be required for treatment. Until newer agents are developed that negate these issues, healthcare providers must strive to better understand the risk factors associated with CM reactions, as well as the available prophylactic and treatment options.

Review article: Acute serious and fatal reactions to contrast media: our current understanding

Serious or fatal reactions to a contrast medium (CM) are unpredictable but fortunately rare. History of serious reaction to CM, bronchial asthma or multiple allergies increases the incidence of serious reactions by a factor of 5. Serious or fatal reaction to CM could be due to direct effect on basophils and mast cells or IgE mediated (type 1 hypersensitivity reaction). Activation of the kinin system leading to the formation of bradykinin could also be involved. Complement activation is unlikely to be a primary factor in initiating a serious reaction to CM. Avoiding CM administration in patients at high risk of serious reaction is advisable, but if the administration is deemed essential all precautions should be implemented and measures to treat serious reactions should be readily available. Oxygen supplementation, intravenous administration of physiological fluids and intramuscular injection of 0.5 ml adrenalin (1:1000) should be considered in the first line management of acute anaphylaxis. The ability to assess and treat serious CM reaction effectively is an essential skill that the radiologist should have and maintain.

A possible role for cysteinyl-leukotrienes in non-ionic contrast media induced adverse reactions

PURPOSE

To test whether mono- or dimeric X-ray contrast media (CM) may induce the de novo production of cysteinyl-leukotriens (cys-LT), that could contribute to allergic/allergy-like side effects.

MATERIALS AND METHODS

Leukocytes from 39 patients receiving iopromide or iotrolan for routine CT-examination were analyzed for the production of cys-LT. Histamine levels were analyzed in plasma specimens. One patient with a positive history of a previous CM-reaction did not receive CM-injection.

RESULTS

Three patients of the iopromide and five of the iotrolan group showed adverse reactions. Reactors had increased cys-LT values in samples obtained before CM-injection induced by the positive control (anti-FcepsilonRI antibodies) (6763.7 pg/ml+/-1367.3 versus 2299.8 pg/ml+/-399.2; p<0.007). Patients with versus without CM-reaction did not differ significantly with respect to their histamine values before CM-administration. In vitro iopromide (p<0.0002) and iotrolan (p<0.0008) induced significant cys-LT production as compared to IL-3 stimulation. In vivo both CM induced a significant increase 6h after CM administration (p<0.05).

CONCLUSION

Our findings suggest that both CM seem to induce cys-LT production. As to whether the observed increased values in pre-dose samples of patients with as compared to those without reactions could contribute to identify high risk patients should be investigated in larger patient groups in future.

« Allergie à l’iode » : le point sur la question

OBJECTIVE

The aim of this literature review is to suggest a diagnostic and a preventive attitude in patients having presented an immediate hypersensitivity reaction due to an iodinated drug.

DATA SOURCES

Literature review. Data were searched in the Medline database from 1967 to 2004 in English and French language. Complementary references were selected from the bibliography of selected references or from authors' personal databases. The following key-words were used separately or combined: Hypersensitivity, Immediate; Allergy; Contrast Media; Povidone-Iodine; Iodine; Iodine Compounds; Iodides; Amiodarone; Seafood, Parvalbumins; Tropomyosin.

STUDY SELECTION

Randomized studies, epidemiological studies, original articles, clinical cases, and letters to the editor were selected.

DATA SYNTHESIS

The implication of iodine has never been demonstrated during allergic hypersensitivity reactions due to iodinated drugs. However, IgE-mediated allergic hypersensitivity reactions have been published with contrast media or iodinated antiseptics and will be described in this development. In a wider sense, allergic hypersensitivity reactions due to seafood are evoked because often improperly considered as a risk factor of allergic reaction to iodinated drugs. The allergenic determinant responsible of patient sensitization is not known for iodinated contrast media, but is probably due to povidone in case of iodine povidone. In fish, the allergen is described as the protein M. There has also been strong immunological evidence that tropomyosin is a cross-reactive allergen among crustaceans and molluscs (shellfishs). In case of hypersensitivity reaction occurring with iodinated drug, an allergological assessment is required to confirm the immune mechanism, to identify the culprit drug or substance and to identify cross-reactivity especially with iodinated contrast media.

CONCLUSION

Asking a patient if he/she is "allergic to iodine" is a question that should be avoided because its significance is null. A diagnosis of drug allergy, essentially relying on clinical symptoms, biological tests and cutaneous tests, is required to take adequate preventive measures.

Histamine H1 and H2 receptor–mediated vasoreactivity of human internal thoracic and radial arteries

BACKGROUND

Although internal thoracic arteries (ITAs) and radial arteries (RAs) have been shown to have similar patency, RAs tend to be more vasospastic postoperatively compared with ITAs. Therefore, the purpose of this study was to examine the effect of histamine subclass 1 (H1) receptors and histamine subclass 2 (H2) receptors on vasoreactivity in human ITAs and RAs.

METHODS

Vessels were obtained from coronary artery bypass grafting patients. Human arterial rings (2 mm) were mounted in tissue baths, and baseline contractility was determined. Histamine concentration response curves (10(-9)-10(-3) mol/L) were performed in the absence or presence of diphenhydramine (H1 antagonist, 10(-4) mol/L) or famotidine (H2 antagonist, 10(-4) mol/L). Comparison of curves was performed by 2-way analysis of variance with repeated measures and a Bonferroni post-t test.

RESULTS

Maximal contraction to histamine was significantly greater in RA (8.3 +/- 0.8 g, n = 6) than in ITA (2.9 +/- 0.3, n = 6), (P < .05). However, there was no difference in sensitivity. Histamine-mediated responses of both RA and ITA were blocked by pre-exposure to H1 antagonist, whereas an H2 antagonist only partially inhibited RA responses while blocking most of the ITA response to histamine.

CONCLUSION

These studies suggest that H1 receptors alone cause contraction in RA but not in ITA, which may have potential linkage to patency and vasospasm. Further studies are necessary to identify the exact role of H2 receptors in ITA.

Screening for mast cell tryptase and serum IgE antibodies in 18 patients with anaphylactic shock during general anaesthesia

BACKGROUND

In the perioperative setting multiple agents can cause anaphylaxis. Often the reactions are dramatic, and due to their lifethreatening potential it is crucial that the responsible agent is identified in order to avoid future adverse reactions. The aim of the present study was to measure the concentration of serum mast cell tryptase (MCT), to investigate the prevalence of serum IgE antibodies against ammonium groups, choline, morphine, suxamethonium, thiopentone and latex and to perform skin prick tests (SPTs) in 18 patients experiencing an anaphylactic reaction during induction of general anaesthesia.

METHODS

Serum samples from 18 patients with an anaphylactic reaction during general anaesthesia were analyzed for MCT and specific IgE against ammonium groups, choline, morphine, suxamethonium, thiopentone and latex. Skin prick tests were performed in 11 out of 18 patients.

RESULTS

Ten patients had elevated MCT levels and specific IgE against ammonium ion, morphine and (with the exception of patient nos 3, 9 and 10) suxamethonium. Seven of these patients had positive SPTs to suxamethonium. One of the patients tested positive to latex in addition to suxamethonium. Two patients showed elevated MCT, while specific IgE against the drugs tested was not detected. Three patients tested positive to ammonium ion, morphine and suxamethonium, but negative to MCT. Three patients tested negative to both MCT and specific IgE.

CONCLUSIONS

Fifteen out of 18 sera tested positive for MCT and/or specific IgE against neuromuscular blocking drugs (NMBDs). Ten of the 18 patients experienced an IgE-mediated anaphylactic reaction to NMBDs during anaesthesia, verified by detection of specific IgE and elevated levels of MCT.

Serum levels of mast cell tryptase, vascular endothelial growth factor and basic fibroblast growth factor in patients with acute pancreatitis

PURPOSE

Mast cell tryptase, vascular endothelial growth factor (VEGF), and basic fibroblast growth factor (bFGF) possibly play a role in the pathogenesis of acute pancreatitis (AP). The aim is to describe their serum levels in relation to severity of AP.

METHODS

Seventy patients with AP were studied. Thirty-one had mild acute pancreatitis and 39 severe AP of whom 21 developed organ dysfunction. Serum concentration of tryptase was determined with fluoroimmunoassay (UniCAP), and VEGF and bFGF with ELISA at admission and on days 1, 2, and 7 post-hospitalization.

RESULTS

The peak tryptase levels and tryptase levels at 2nd day after symptom onset, although mostly within normal range, were significantly higher in patients with organ dysfunction than in patients without organ dysfunction (6.6 microg/l (inter quartile range 4.8 to 12.6) versus 4.0 microg/l (2.7 to 6.2); P = 0.018 and 6.0 microg/l (4.4 to 7.6) versus 3.4 microg/l (2.3 to 4.8); P = 0.006, respectively). Median serum VEGF and bFGF concentrations increased during follow-up, were significantly higher on day 7 than on days 0, 1, and 2, but were not related to development of organ dysfunction.

CONCLUSIONS

Mast cell activation, as defined by serum tryptase levels, may play a role in the development of remote organ dysfunction in patients with AP. However, neither tryptase nor the factors VEGF and bFGF serve as predictors of organ dysfunction in clinical AP.

Characterization of histamine release induced by fluoroquinolone antibacterial agents in-vivo and in-vitro

Characterization of histamine release induced by fluoroquinolone antibacterial agents, levofloxacin and ciprofloxacin, was investigated in-vivo and in-vitro. Intravenous injection of levofloxacin and ciprofloxacin at 1-10 mg kg(-1) produced dose-related elevations in plasma histamine level in anaesthetized dogs. In contrast, levofloxacin was devoid of plasma histamine increment in anaesthetized rats at 100 mg kg(-1), whereas ciprofloxacin at the same dose caused endogenous histamine release. Levofloxacin and ciprofloxacin induced non-cytotoxic secretion of histamine from all mast cells tested in a concentration-dependent manner, whereas rat skin and peritoneal mast cells were thirty- to one-hundred-times less sensitive to the effect of fluoroquinolones as compared with the canine skin mast cells. These results suggest that the functional heterogeneity of mast cells from different species in histamine releasing activity of fluoroquinolones may exist, and that mast cells from the dog appear to be particularly sensitive to the effect of the fluoroquinolones.

Detection of IgE antibody to a radiocontrast medium

BACKGROUND

Very little is known about the mechanisms underlying adverse reactions to radiocontrast medium. On the basis of the clinical features of the adverse reactions, it has generally been considered that an IgE-dependent mechanism is not involved in these adverse reactions, and only a few studies have demonstrated the presence of IgE antibody to radiocontrast medium in patient sera.

METHODS

We assayed for IgE antibody to ioxaglic acid (Hexabrix), a representative radiocontrast medium, in the sera of patients who had developed adverse reactions to ioxaglic acid. A conjugate was prepared by coupling succinyl ioxaglic acid to human serum albumin. Enzyme immunoassay and radioimmunoassay for the detection of IgE antibody to ioxaglic acid in patient sera were constructed by physical adsorption or by covalent coupling of the conjugate on solid supports.

RESULTS

When the radioactivity or the absorbance exceeding the mean plus 3 SD for normal healthy subjects was regarded as positive, IgE antibody was detected in the sera of 47.1% of the patients who had a past history of adverse reactions to ioxaglic acid and 16.2% of those who had experienced adverse reactions to ioxaglic acid within 24 h before the blood collection, although the IgE antibody levels were low. On the other hand, IgE antibody to ioxaglic acid was not detected in the sera of patients with no history of adverse reactions to ioxaglic acid. Inhibition experiments revealed the presence of IgE antibody specific to ioxaglic acid in the serum defined as positive for IgE antibody to ioxaglic acid. The presence of IgE antibody to ioxaglic acid did not always correlate with the activation of mast cells due to the occurrence of adverse reactions to ioxaglic acid.

CONCLUSIONS

A small amount of IgE antibody to ioxaglic acid was detected in the sera of some patients with a history of adverse reactions to ioxaglic acid, and these adverse reactions may be partly explained by the presence of IgE antibody in the serum of at least some patients.