磺胺类药物过敏和交叉过敏的研究进展

磺胺类药物是指含有-SO2NH2结构的药物。磺胺类药物的交叉过敏仍是困扰临床的一个用药难题。有磺胺类抗菌药过敏史的患者在临床上并不罕见,这些患者是否可以使用其他磺胺类药物,相关药品说明书的描述并不一致,也无标准的操作流程或指南。本文回顾了磺胺类抗菌药发生超敏反应的机制,发现其发生主要与磺胺类抗菌药N4位的芳香胺取代基和N1位的杂环取代基有关,而多数磺胺类非抗菌药(如呋塞米、噻嗪类利尿剂、塞来昔布等)并不含有这两个取代基,因此磺胺类抗菌药和非抗菌药之间发生交叉过敏的可能性较低。此外,本文也对磺胺类药物交叉过敏的相关临床研究进行了回顾。一个大规模的回顾性研究提示,有磺胺类抗菌药过敏史者使用磺胺类非抗菌药过敏反应的发生率较无磺胺过敏史者高,但并非与磺胺基团有关,而是和患者本身过敏反应易感性高有关。磺胺类抗菌药和非抗菌药之间发生交叉过敏的理论和循证依据尚不充分,但鉴于有磺胺类抗菌药过敏史的患者对药物过敏的易感性较高,这些患者是否可使用其他磺胺类药物,取决于相关药品说明书的规定、既往发生过敏反应的严重程度以及是否有其他替代药物。     

Should celecoxib be contraindicated in patients who are allergic to sulfonamides? Revisiting the meaning of 'sulfa' allergy.

Celecoxib, a selective cyclo-oxygenase-2 inhibitor, is a diaryl-substituted pyrazole derivative containing a sulfonamide substituent. Because of this structural component, celecoxib is contraindicated for use in patients who have demonstrated allergic reactions to sulfonamides. However, there is a lack of data demonstrating cross-reactivity among sulfonamide medications. A sulfonamide is any compound with an SO2NH2 moiety. The major difference between sulfonamide antimicrobials and other sulfonamide-containing medications such as furosemide, thiazide diuretics and celecoxib, is that sulfonamide antimicrobials contain an aromatic amine group at the N4 position. This allows for division of the sulfonamides into 2 groups: aromatic amines (i.e., sulfonamide antimicrobials) and nonaromatic amines. In addition, sulfonamide antimicrobials contain a substituted ring at the N1-position; this group is not found with nonaromatic amine-containing sulfonamides. Adverse reactions to sulfonamide antimicrobials include type I, or immunoglobulin (Ig) E-mediated reactions, hypersensitivity syndrome reactions, and severe skin reactions such as toxic epidermal necrolysis. The aromatic amine portion of the sulfonamide antimicrobial is considered to be critical in the development of latter 2 reactions. In susceptible individuals, the hydroxylamine metabolite is unable to be detoxified leading to a cascade of cytotoxic and immunological events that eventually results in the adverse reaction. Since celecoxib does not contain the aromatic amine, adverse reactions such as hypersensitivity syndrome reactions and toxic epidermal necrolysis would not be expected to occur at the same frequency as they do with sulfonamide antimicrobials. Similarly, for IgE-mediated reactions, the N1-substituent and not the sulphonamide moiety is important in determining specificity to antibodies. Celecoxib and other nonaromatic amine-containing sulfonamide medications do not contain the N1-substituent. Cross-reactivity among the various sulfonamide-containing medications has also not been substantiated by published case reports. In fact, conflicting information exists in the literature. Reports showing lack of cross-reactivity balance the few case reports suggesting cross-reactivity. Cross-reactivity between sulfonamide medications should be based on scientific data, including chemistry, metabolism, immune responses and clinical data. Based on the current information, there is no documentation for cross-reactivity between sulfonamide antimicrobials and other sulfonamide medications, such as celecoxib.     

Severe Allergic Reaction to Hydrochlorothiazide Mimicking Septic Shock

Hydrochlorothiazide (HCTZ) is a sulfonamide-containing drug with commonly reported adverse effects that include electrolyte abnormalities, orthostatic hypotension, hyperglycemia, and photosensitivity. A few reports have described rare but serious drug complications such as interstitial pneumonitis, angioedema, and aplastic anemia. We describe a patient who experienced a serious HCTZ-induced adverse event that, to our knowledge, has not yet been reported in the literature. A 78-year-old woman came to the emergency department with dyspnea and severe fatigue; her signs and symptoms were suggestive of septic shock from pneumonia. She was treated accordingly, her condition improved, and she was discharged home. During the next 2 months, the patient returned to the emergency department 2 more times and was hospitalized each time with the same diagnosis. During her third admission, it was discovered that the patient's primary care physician had restarted her HCTZ for hypertension after it had been discontinued during each of the first two hospitalizations. The patient's symptoms began within hours of the first and second hospitalizations and almost immediately after taking a dose of HCTZ on the day of the third hospitalization. Her medical history revealed documented allergic reactions to sulfonamide drugs and penicillin; thus a hypersensitivity reaction to HCTZ was suspected. Use of the Naranjo adverse drug reaction probability scale indicated a probable relationship between the patient's hypersensitivity reactions and HCTZ therapy. Because of a lack of evidence showing cross-reactivity among the different classes of sulfonamides, the mechanism of the allergic reaction to HCTZ was unlikely to be cross-sensitivity between sulfonamide antibio tics and sulfo namide nonantibiotic drugs. Although the mechanism is not clear, evidence shows that the allergy to the HCTZ (sulfonamide nonantibiotic) may be due to a predisposition to drug allergies rather than sulfonamide cross-sensitivity. Clinicians should be aware of the potential for these types of allergic reactions.     

Knowledge and attitudes of American pharmacists concerning sulfonamide allergy cross-reactivity

Objective Pharmacists are commonly confronted with patients with a history of sulfonamide allergy. Basic immunologic and clinical data suggest a low likelihood of a patient with a history of sulfonamide hypersensitivity developing an allergic reaction to a non-antimicrobial sulfonamide drug. We conducted a survey to describe the knowledge and attitudes of licensed pharmacists concerning sulfonamide allergy cross-reactivity. Methods A survey instrument was developed and sent to all licensed pharmacists in the state of Iowa. The survey recorded demographic information and included six patient scenarios designed to elicit responses concerning sulfonamide allergy cross-reactivity with a number of non-antimicrobial sulfonamides. Results A total of 421 surveys were returned for a 39% response rate. There was a wide discrepancy in approaches to patients with a history of sulfonamide allergy prescribed a sulfonamide containing non-antibiotic. Differences depended on previous history of tolerating the medication in question, the degree of cautionary statements in product literature, and the familiarity the pharmacist had with the product. Conclusion Our survey suggests a significant diversity in knowledge and attitudes of pharmacists concerning cross-reactivity of sulfonamide antimicrobials and other drugs with a sulfonamide moiety. Depth of training in this area may be an associative factor.     

Safety of celecoxib in individuals allergic to sulfonamide: a pilot study.

OBJECTIVE: To evaluate cross reactivity between sulfonamide antimicrobials and celecoxib in patients with histories of allergies to sulfonamide antimicrobials. METHODS: Immunocompetent patients with a history of sulfonamide antimicrobial allergy who were being considered for therapy with celecoxib were prospectively enrolled. Sulfamethoxazole and trimethoprim skin prick and intradermal testing and/or an in vitro lymphocyte toxicity assay were performed. If skin testing was negative, an oral challenge with sulfamethoxazole and trimethoprim was performed. Oral challenges with celecoxib were administered to all patients. RESULTS: Twenty-eight immunocompetent patients (26 female; mean age 60 years) were evaluated. History of sulfonamide antimicrobial allergy included urticaria (n = 7), cutaneous eruptions (n = 9), and other (n = 12). Four of the 28 patients who were skin prick tested were positive to sulfamethoxazole and two of the ten patients who underwent in vitro testing were positive to sulfamethoxazole. All 28 patients were administered celecoxib and tolerated the medication. Phone call follow up in 25 patients disclosed that 15 patients continued to take celecoxib, while five patients did not take celecoxib following the oral challenge, and five discontinued celecoxib due to adverse effects, lack of drug efficacy or physician preference. CONCLUSIONS: Confusion exists regarding the potential for cross reactivity between sulfonamide antimicrobials and other sulfonamide-containing compounds. The six sulfonamide-allergic patients tolerated celecoxib uneventfully. This pilot study supports the hypothesis that the potential for cross-reactivity between celecoxib and sulfonamide antimicrobials appears to be low. However, further investigations are required to confirm this.     

Hypersensitivity to aromatic anticonvulsants: in vivo and in vitro cross-reactivity studies

Aromatic antiepileptic drugs (phenytoin, carbamazepine, oxcarbazepine, and phenobarbital) are frequently associated with cutaneous eruptions. A cell-mediated pathogenic mechanism has been demonstrated in most of such reactions on the basis of positive responses to patch tests and/or lymphocyte transformation tests. Therefore, such tests are useful tools for evaluating anticonvulsant hypersensitivity reactions. Moreover, an in vitro lymphocyte toxicity assay, which exposes the patient's lymphocytes to arene oxides, has detected lymphocyte susceptibility to toxic metabolites in a large percentage of patients with hypersensitivity reactions to aromatic anticonvulsants. Although several hypersensitivity reactions to sequential exposure to more than one aromatic anticonvulsant (i.e., clinical cross-reactivity) have been reported, there are few studies performed with patch tests and/or lymphocyte transformation tests assessing immunologic cross-reactivity, and their data are contradictory. In any case, considering studies performed in samples of at least 10 patients, the immunologic cross-reactivity rate among aromatic anticonvulsants appears to be low. On the other hand, the reported rate of the toxic cross-reactivity (i.e., assessed by lymphocyte toxicity assays) is high. Further in vivo and in vitro studies in large samples of subjects are needed to evaluate cross-reactivity among aromatic anticonvulsants.     

The sulfonamide group as a structural alert: A distorted story?

The sulfonamide group is widely used in medicinal chemistry and appears in many marketed drugs in a variety of forms. One class of drugs that contain this group has been termed the 'sulfonamide antibacterials'. These compounds are inhibitors of tetrahydropteroic acid synthetase. Sulfonamide antibacterials are derivatives of 4-aminobenzenesulfonamide, in which the sulfonamide moiety acts as an isostere of the carboxylic acid group of the natural substrate 4-aminobenzoic acid. The 4-amino group is essential for activity in this class of compounds. These drugs, however, can cause hypersensitivity and severe skin rash, toxicities which are now associated with the presence of the aniline structure (4-amino), although, historically, the class affect was referred to as 'sulfa allergy'. This class effect has also been wrongly associated with other sulfonamide-containing drugs in a number of cases, and has led to warnings and labels that are not scientifically correct. This review explains how this confusion arose and illustrates the scientific evidence indicating that the sulfonamide group is an essential and safe part of the medicinal chemist's arsenal.     

Haptenation of sulfonamide reactive metabolites to cellular proteins

Adverse drug reactions are a major problem complicating medical therapy. The pathogenesis of many severe adverse drug reactions, notably hypersensitivity reactions, is poorly understood. The sulfonamides are associated with severe hypersensitivity reactions. The initial pathogenesis seems to be caused by bioactivation of the parent drug to a reactive intermediate and subsequent propagation by the immune system. The determinants of the immune response are not known. We explored the formation of sulfonamide haptens in Molt-3 and HEPA 1C1C7 cells after incubation with sulfamethoxazole (SMX), the hydroxylamine of sulfamethoxazole (SMX-HA), or the nitroso of sulfamethoxazole (SMX-NO). Haptenation was demonstrated with SMX-HA and SMX-NO but not SMX; this occurred at concentrations below that associated with toxicity (significant haptenation was seen at 25 to 50 microM). Thus, haptenation occurred presumably onto viable cells. Haptenation occurred rapidly; haptenation of cell surface proteins was demonstrated within 5 min. This did not occur indiscriminately; confocal microscopy demonstrated haptenation onto specific sites on the cell membrane. We found that haptenation was significantly inhibited by thiols and other antioxidants (p < 0.05). Sulfonamide-specific haptens were rapidly internalized by what seemed to be a caveolae-dependent process. It seems that sulfonamide reactive metabolites haptenated specific cell surface proteins that are rapidly internalized. Understanding the specific protein target(s) for haptenation and how these haptens are processed will be important in understanding the immune mediation of sulfonamide hypersensitivity adverse drug reactions.     

Transfection of drug-specific T-cell receptors into hybridoma cells: tools to monitor drug interaction with T-cell receptors and evaluate cross-reactivity to related compounds

In the context of drug hypersensitivity, our group has recently proposed a new model based on the structural features of drugs (pharmacological interaction with immune receptors; p-i concept) to explain their recognition by T cells. According to this concept, even chemically inert drugs can stimulate T cells because certain drugs interact in a direct way with T-cell receptors (TCR) and possibly major histocompatibility complex molecules without the need for metabolism and covalent binding to a carrier. In this study, we investigated whether mouse T-cell hybridomas transfected with drug-specific human TCR can be used as an alternative to drug-specific T-cell clones (TCC). Indeed, they behaved like TCC and, in accordance with the p-i concept, the TCR recognize their specific drugs in a direct, processing-independent, and dose-dependent way. The presence of antigen-presenting cells was a prerequisite for interleukin-2 production by the TCR-transfected cells. The analysis of cross-reactivity confirmed the fine specificity of the TCR and also showed that TCR transfectants might provide a tool to evaluate the potential of new drugs to cause hypersensitivity due to cross-reactivity. Recombining the alpha- and beta-chains of sulfanilamide- and quinolone-specific TCR abrogated drug reactivity, suggesting that both original alpha- and beta-chains were involved in drug binding. The TCR-transfected hybridoma system showed that the recognition of two important classes of drugs (sulfanilamides and quinolones) by TCR occurred according to the p-i concept and provides an interesting tool to study drug-TCR interactions and their biological consequences and to evaluate the cross-reactivity potential of new drugs of the same class.     

Cross-reactivity among drugs: clinical problems

Cross-reactivity among drugs is either mediated by immunologic mechanisms or not. The former kind is usually explained by the presence of common antigenic determinants in the cross-reacting drugs. In the case of compounds provoking non-allergic hypersensitivity reactions, cross-reactivity is explained by a common pharmacological characteristic, such as the inhibitory effect of non-steroidal anti-inflammatory drugs on cyclooxygenase-1 and the capability of muscle relaxants or contrast media to release histamine through a non-immunologic mechanism. The main clinical problem deriving from cross-reactivity among drugs is the compelling need to choose a potentially cross-reactive compound and, therefore, to assess cross-reactivity by diagnostic tests. In choosing alternative compounds, skin testing has been used in evaluating IgE-mediated cross-reactivity between penicillins and cephalosporins, as well as among muscle relaxants. In assessing T cell-mediated cross-reactivity among contrast media, corticosteroids, anticonvulsants and heparins, delayed-reading intradermal tests and patch tests, together with lymphocyte transformation tests, can be performed. Because of the limited sensitivity of in vivo and in vitro testing, the most prudent way of establishing the tolerability of a compound of the same group in patients who especially require one is a graded challenge when other allergologic tests are negative.     

Clinical importance of carbapenem hypersensitivity in patients with self-reported and documented penicillin allergy

The risk of carbapenem hypersensitivity in patients with self-reported or documented penicillin allergy needs to be determined so that practitioners can make better-informed decisions regarding antibiotic therapy for this patient population. The risk of cross-reactivity between penicillin and carbapenem antibiotics initially was reported to approach 50%. Recent retrospective studies have suggested that the clinical risk of cross-hypersensitivity between these two drug classes is 9.2-11%, which is significantly lower than initially reported. Patients whose history of penicillin allergy is self-reported and is not type 1 may be at moderate risk for hypersensitivity when treated with a carbapenem antibiotic. The risk of hypersensitivity appears to be higher in patients whose penicillin allergy was documented by a health care provider, those with several antibiotic allergies, and those with a positive penicillin skin test result or a history of type 1 penicillin hypersensitivity.     

Use of constraint-based modeling for the prediction and validation of antimicrobial targets

The overall process of antimicrobial drug discovery and development seems simple, to cure infectious disease by identifying suitable antibiotic drugs. However, this goal has been difficult to fulfill in recent years. Despite the promise of the high-throughput innovations sparked by the genomics revolution, discovery, and development of new antibiotics has lagged in recent years exacerbating the already serious problem of evolution of antibiotic resistance. Therefore, both new antimicrobials are desperately needed as are improvements to speed up or improve nearly all steps in the process of discovering novel antibiotics and bringing these to clinical use. Another product of the genomic revolution is the modeling of metabolism using computational methodologies. Genomic-scale networks of metabolic reactions based on stoichiometry, thermodynamics and other physico-chemical constraints that emulate microbial metabolism have been developed into valuable research tools in metabolic engineering and other fields. This constraint-based modeling is predictive in identifying critical reactions, metabolites, and genes in metabolism. This is extremely useful in determining and rationalizing cellular metabolic requirements. In turn, these methods can be used to predict potential metabolic targets for antimicrobial research especially if used to increase the confidence in prioritization of metabolic targets. The many different capacities of constraint-based modeling also enable prediction of cellular response to specific inhibitors such as antibiotics and this may, ultimately find a role in drug discovery and development. Herein, we describe the principles of metabolic modeling and how they might initially be applied to antimicrobial research.     

Immediate hypersensitivity reactions to penicillins and other betalactams

Immediate hypersensitivity reactions to betalactams are IgE mediated and constitute the most frequent allergic reactions mediated by specific immunological mechanisms. IgE responses to benzyl penicillin (BP), the first antibiotic producing the benzyl penicilloyl structure (BPO), are characterized by a quick release of inflammatory mediators, resulting in anaphylactic shock, urticaria and angioedema. With the progressive appearance of other structures, comprising cephalosporins, carbapenems, monobactams and clavulanic acid, IgE selective responses and cross-reactivity reactions were observed. The diagnosis of betalactam hypersensitivity, classically based on skin testing with major and minor determinants of benzyl penicillin or in vitro IgE antibodies to BP, has been modified by the inclusion of different determinants generated from these compounds, for which amoxicillin (AX) is the most relevant, followed by cephalosporins. Some subjects develop positive responses to several betalactams, mostly within the same family, but others develop a selective response. These are relevant for the appropriate selection of antimicrobial drugs in patients who have immediate hypersensitivity to betalactams.     

抗菌药物诱发急性溶血性贫血临床特点分析

目的：探讨临床常用抗菌药物诱发溶血性贫血的特点。方法：回顾某科发生的头孢唑肟引起溶血性贫血2例患者临床资料,同时在MEDLINE光盘数据库、中国知网中国期刊全文数据库、中国科技期刊全文数据库及万方数据库检索,搜集114例抗菌药物诱发溶血性贫血病例资料,分析其临床及实验室特点。结果：共搜集116例抗菌药物引起溶血性贫血病例,儿童50例,成人66例。报道最多抗菌药物为头孢菌素,其次为青霉素及磺胺类抗菌药物,喹诺酮类及大环内酯类抗菌药物引起溶血性贫血亦有散在病例报道。溶贫发生时抗菌药物应用时间最短为5 min,最长为21 d,69.8%发生在抗菌药物应用1周内。临床症状不典型,表现多样,发热、恶心呕吐、疲劳、腰背疼痛为常见临床表现,常伴有血清白细胞及乳酸脱氢酶明显增高。最常见并发症为肾功能衰竭,其次可有肝功能异常、凝血异常、血小板减少等。42.3%患者出现初始症状及时停药,57.7%患者未及时停药,最终24例死亡。结论：抗菌药物引起溶血性贫血罕见但可致死,及时识别并停药对于改善预后至关重要,临床医师在抗菌药物应用中应随时警惕这一致命性不良反应发生的可能。     

Studies on concentrations in body fluids of 16-membered ring macrolide antibiotics upon oral administration to healthy volunteers. Effects of their metabolites on bioassay values

Plasma and urinary antibiotic concentrations measured by 3 different bioassay methods were compared to each other in vitro, after oral administrations of rokitamycin (RKM) tablet, midecamycin acetate (MOM) tablet or josamycin (JM) tablet at a dose of a potency of 600 mg to each of nine healthy volunteers. Method I (RKM bioassay method) was an agar-well method using the agar medium described in the Minimum Requirements for Antibiotic Products of Japan (MRAPJ medium, pH 6.5), method II (MOM bioassay method) was an agar-well method using mycin-assay agar (pH 8.0) and method III (JM bioassay method) was an agar-well method using nutrient agar (pH 7.8). Micrococcus luteus ATCC 9341 was used as the test organism in all the assay method. With any of the bioassay methods tested, plasma concentrations of RKM were determined to be higher than those of MOM or JM. When the three different bioassay methods were compared, method II and III gave consistently higher values than method I for plasma concentrations of any of the drugs tested. These higher values obtained by method II and III appeared to be due to their inability to correctly assay potencies of metabolites of these antibiotics. Using in vitro assay method, potencies of metabolites were found to be estimated higher than they should when method II and III were used. Method I, on the other hand, determined relative potencies of these antibiotics and their metabolites correctly, reflecting differences in MIC values of original antibiotics and their metabolites. Method I, therefore, should be used as the method of preference to determine concentrations of these drugs in body fluids.     

小单孢菌及其产生的次级生物活性代谢产物

原核微生物小单孢菌产生了740多个生物活性物质，化学结构类型多样，生物活性各异，主要为抗生素和一些人体酶抑制剂。小单孢菌不但能产生链霉菌产生的抗生素化学类型而且还有其独到之处。最受人重视的抗生素是庆大霉素、最主要的特征是产生氨基糖苷类抗生素和大环内酯类抗生素。福建省微生物研究所自20世纪60年代成功研发庆大霉素之后不问断地从我国各地水生环境中分离到多种抗生素、几种酶抑制剂和其他生物活性物质。本文还阐述近年来国外在小单孢菌中发现的一些有实用价值和有前途的微生物新药物，特别是烯二炔类抗肿瘤抗生素。     

A Review of the Therapeutic Efficacy of Aerosolized and Endotracheally Instilled Antibiotics

Achievement of sufficient concentrations of aerosolized antibiotic at the site of infection is limited by technical problems in antibiotic delivery and by drug inactivation. Antibiotic delivery by aerosolization is generally associated with minimal systemic absorption, whereas systemic absorption may be significant after endotracheal instillation. Methodologic problems make correlations between clinical response and sputum antibiotic concentrations difficult. Studies suggest that aerosolized antibiotics are of little value in the treatment of chronic bronchopulmonary infections. Endotracheal instillation appears to be associated with favorable clinical responses, possibly due to enhanced antibiotic delivery to the site of infection. Prophylactic aerosolized antibiotics are effective in altering sputum flora; reduction in mortality from acquired pneumonia has not been demonstrated. The development of resistant organisms may occur as a result of prophylactic treatment.     

Unexpected nanomolar inhibition of carbonic anhydrase by COX-2-selective celecoxib: new pharmacological opportunities due to related binding site recognition

By optimizing binding to a selected target protein, modern drug research strives to develop safe and efficacious agents for the treatment of disease. Selective drug action is intended to minimize undesirable side effects from scatter pharmacology. Celecoxib (Celebrex), valdecoxib (Bextra), and rofecoxib (Vioxx) are nonsteroidal antiinflammatory drugs (NSAIDs) due to selective inhibition of inducible cyclooxygenase COX-2 while sparing inhibition of constitutive COX-1. While rofecoxib contains a methyl sulfone constituent, celecoxib and valdecoxib possess an unsubstituted arylsulfonamide moiety. The latter group is common to many carbonic anhydrase (CA) inhibitors. Using enzyme kinetics and X-ray crystallography, we demonstrate an unexpected nanomolar affinity of the COX-2 specific arylsulfonamide-type celecoxib and valdecoxib for isoenzymes of the totally unrelated carbonic anhydrase (CA) family, such as CA I, II, IV, and IX, whereas the rofecoxib methyl sulfone-type has no effect. When administered orally to glaucomatous rabbits, celecoxib and valdecoxib lowered intraocular pressure, suggesting that these agents may have utility in the treatment of this disorder. The crystal structure of celecoxib in complex with CA II reveals part of this inhibition to be mediated via binding of the sulfonamide group to the catalytic zinc of CA II. To investigate the structural basis for cross-reactivity of these compounds between COX-2 and CA II, we compared the molecular recognition properties of both protein binding pockets in terms of local physicochemical similarities among binding site-exposed amino acids accommodating different portions of the drug molecules. Our approach Cavbase, implemented into Relibase, detects similarities between the sites, suggesting some potential to predict unexpected cross-reactivity of drugs among functionally unrelated target proteins. The observed cross-reactivity with CAs may also contribute to differences in the pharmacological profiles, in particular with respect to glaucoma and anticancer therapy and may suggest new opportunities of these COX-2 selective NSAIDs.