Cephalosporins In Patients Research Articles

Antimicrobial resistance in surgical infections: experience from open tibia fracture-related infection intraoperative tissue specimens

Background Antimicrobial resistance in surgical infections is known to have significant morbidity and mortality in extreme cases on top of increased costs in medical expenditure. This study aimed to analyze antimicrobial resistance patterns of microbes in open tibia fracture-related infection (FRI) using intraoperative tissue samples. Methods Between January and June 2022, a descriptive cross-sectional observational study was conducted involving patients aged 18 and above with open tibial shaft fractures. Microbiological culture and sensitivity of three intraoperative deep tissue and bone samples taken by sterile techniques using separate instruments in patients with infection. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disk diffusion method along with biomechanical tests for microbial identification. Results Fifty-seven deep tissue samples were taken from 19 patients with FRI who underwent surgery during the study period were analyzed. Almost all (96.5%) intraoperative tissue samples were culture-positive identifying 73 bacterial isolates out of which 57.9% were polymicrobial. The most frequent isolated bacteria were Gram-negative bacteria 56 (76.7%) with a predominance of Proteus spp 13 (17.8%). Methicilin Resistance Staphyaureus comprised 12 (16.4%) of the isolates whereas Inducible Clindamycin resistance was identified in 8 (57.1%) of Staphyloccus aureus isolates. More than half of the isolates 30 (53.6%) comprised of Extended Spectrum Beta Lactamase producing bacteria. There was high resistance to Cephalosporins and Amoxyclavulanic acid as the efficacy was low ranging from 28.2, 27.8, and 30.0% for cefotaxime, ceftazidime and amoxicillin/clavulanic acid, respectively. Almost all Gram-negative bacteria 47 (83.9%) had multidrug resistance pattern except for Pseudomonas aureginosa that had 77.8 to 88.9% susceptibility to all tested antibiotics. Conclusion High resistance to cephalosporins in patients with delayed or late infection in open tibia FRI is alarming and further studies to establish causes are indicated.

Evaluation of Cross-Reactivity Between Penicillins and Cephalosporins in Children with a History of Cephalosporin Allergy.

The cross-reactivity problem between cephalosporins and penicillins has mainly been evaluated in the context of patients allergic to penicillins. However, we have little data regarding the opposite aspect of the problem, i.e. the cross-reactivity in subjects primarily sensitized to cephalosporins. This prospective study aims to evaluate the cross-reactivity to penicillins and some other cephalosporins in patients with immediate allergic reactions to cephalosporins. The study included 21 children with immediate allergic reactions to at least one cephalosporin. Skin testing was performed with a panel of minor and major determinant mixtures of penicillins and three commonly used cephalosporins (cephazoline, cefuroxime and ceftriaxone). The children had used 5.14±4.91 (1-15) times any beta-lactam antibiotic in the previous year and the most common cephalosporins accused were ceftriaxone (42.92%), and cefuroxime, cefazolin, cefixime, cefprozil and cefotaxime (9.5% each). Skin tests were positive for any cephalosporin in 14 (66.7%) subjects and penicillin allergens in 15 (71.4%) subjects. Totally, 85.7% of children with a positive allergy history to cephalosporins were found to be sensitive to either penicillin or any one of three cephalosporins. There seems to be a high risk of adverse reactions to penicillins and other cephalosporins in children with a history of type I hypersensitivity reaction to cephalosporins. Therefore, skin testing with both cephalosporins and penicillins should be performed in patients with a history of cephalosporin allergy.

Surgical prophylaxis in pediatric orthopedic patients with penicillin allergy: a multicentered retrospective prognostic study.

Up to 20% of orthopedic surgeons still avoid the use of cephalosporins in patients with penicillin allergies despite its reported safety in the adult and general surgery pediatric population. The primary objective is to determine the incidence of adverse effects and allergic reactions when using cephalosporins in pediatric orthopedic patients labeled as penicillin-allergic as compared to those without previously reported penicillin allergy. A multicenter retrospective chart review was performed across three level 1 trauma centers from January 2013 to February 2020 to identify penicillin-allergic as well as non-penicillin-allergic pediatric patients treated for orthopedic injuries. Data were collected regarding patient demographics, antibiotic administered, timing of antibiotic administration, reported drug allergy, and described allergic reaction. Postoperative or intraoperative allergic reactions to antibiotics, surgical site infections, and complications were recorded. A total of 2289 surgeries performed by four fellowship-trained surgeons were evaluated. Eighty-five patients diagnosed with penicillin allergy were identified and underwent 95 surgeries and 95 patients without previously reported penicillin allergy underwent 95 surgeries. One patient, with a documented history of anaphylaxis to cefazolin, sustained an anaphylactic reaction intraoperatively to cefazolin. There were no other reported reactions, surgical site infections, or complications. There was no statistically significant difference in rate of allergic reaction in patients with previously reported penicillin allergy treated with cefazolin and those with no previous reported reaction ( P > 0.05). Prophylaxis with cephalosporins is not associated with increased risk for allergic reaction. Cephalosporins can be safely administered to pediatric patients with penicillin allergy undergoing orthopedic intervention. Level of evidence: Level II, Multicenter Retrospective Prognostic Study.

O03 Penicillin and cephalosporin cross-reactivity: a single-centre UK study

Abstract Background Penicillin allergy (PenA) labels limit antimicrobial options, and concerns about cross-reactivity between penicillin and cephalosporins can further restrict prescribing. Alternative therapies are associated with reduced efficacy, poorer safety profiles and increased healthcare costs. Emerging literature suggests the incidence of cross-reactivity between penicillins and cephalosporins may be lower than historically reported rates of 2–10%. Furthermore, there is a lack of real-time data evaluating the percentage of patients with PenA who tolerate a cephalosporin. Objectives To determine the percentage of patients with a PenA label who tolerated cephalosporins in a secondary care setting. Methods Patients prescribed a cephalosporin from 01 January 2016 to 31 December 2020 at Leeds Teaching Hospitals NHS Trust (LTHT) were identified using the inpatient electronic prescribing system. 1613 with a PenA label were extracted for analysis. The team reviewed and clarified whether each patient (i) had a PenA label that was a potential hypersensitivity reaction, intolerance, or unknown/undocumented label and (ii) tolerated a cephalosporin. Tolerance was defined as receiving ≥1 dose without adverse effects or subsequent cephalosporin allergy label. We recorded if allergy or intolerance was a documented reason for stopping the cephalosporin. Results There were 1279 patients with a PenA label that received a cephalosporin. 555 (43%) had documentation in-keeping with a potential IgE-mediated allergic reaction to penicillins, 177 (14%) were deemed to have an intolerance and 547 (43%) had an unknown or undocumented label. 1263 (98.7%) patients tolerated a cephalosporin. Six (0.5%) patients stopped due to intolerance. One patient asked to stop therapy due to ‘changes’ in the skin. Nine (0.7%) patients developed possible allergic symptoms to cephalosporin; 4 patients developed a rash, 2 patients developed facial or lip swelling (without airway compromise), 1 patient developed hypotension, 1 patient developed difficulty breathing and 1 patient developed chest pain, breathlessness and itching. Of the 9 patients that had reactions; 5 had documented PenA labels that were classified as potential hypersensitivity reactions. Four patients had unknown or undocumented reactions to penicillins. Eight patients received a 2nd-generation cephalosporin (cefuroxime) and 1 received a 3rd generation (cefotaxime). Conclusions The rate of potential hypersensitivity reaction following administration of a cephalosporin in patients with any PenA label at LTHT was 0.7%. The incidence of cephalosporin allergy is estimated to be 1–3% of the general population (with/without PenA label). We conclude that, for patients with a history of unverified, non-anaphylactic PenA label, any cephalosporin could be administered without an increased risk of hypersensitivity reaction.

Prevalence of enterococcal groin colonization in patients undergoing cardiac interventions: challenging antimicrobial prophylaxis with cephalosporins in patients undergoing transcatheter aortic valve replacement

Cephalosporins are recommended for prophylaxis before transcatheter aortic valve replacement (TAVR). Infective endocarditis (IE) after TAVR is caused by enterococci in up to 30% of cases, particularly early after TAVR. Enterococcal colonization in the groin has been postulated as a source of infection, not only because prophylaxis does not cover enterococci but also because most TAVR procedures are performed by transfemoral access. There are few data analysing the groin microbiome to demonstrate the presence of enterococci. To assess the prevalence of enterococci in the groins of cardiological patients receiving transfemoral interventions. This prospective cohort study was undertaken at University Hospital Basel, Switzerland between February and August 2020. Two skin swabs were taken from the groins of consecutive patients undergoing transfemoral cardiac interventions before the administration of antibiotic prophylaxis; for each patient, swabs were taken before and after groin disinfection. Swabs were analysed in the local microbiological laboratory following validated culture methods. Of 290 included patients, 245 (84.5%) underwent coronary angiography, 31 (10.7%) underwent TAVR, eight (2.8%) underwent right heart catheterization, five (1.7%) underwent closure of patent foramen ovale, and one (0.3%) underwent a MitraClip procedure. Enterococci were detected before disinfection in 48 patients, enterococci were still cultured after disinfection in three patients, and enterococci were detected after disinfection alone (i.e. not detected before disinfection) in one patient. The prevalence of enterococci was 16.6% before disinfection and 1.4% after disinfection. Patients colonized with enterococci had a significantly higher body mass index and were more likely to be diabetic than uncolonized patients. Common enterococcal colonization of the groin, coupled with frequent isolation of enterococci from patients with TAVR-associated IE, provides strong evidence that the current recommendation of antimicrobial prophylaxis with cephalosporins before TAVR should be changed to antimicrobial prophylaxis with a compound that is active against enterococci.

143. Use of First-Generation Cephalosporins in Patients with Serious Penicillin Allergies

BackgroundPenicillin allergies have a negative impact on patient outcomes due to utilization of second-line agents. Newer data suggests cephalosporins are well tolerated in penicillin allergies; however, none have solely evaluated anaphylactic penicillin allergies with first-generation cephalosporins. The purpose of this study was to evaluate the risk of any allergic reaction to first-generation cephalosporins compared to aztreonam in patients reporting anaphylaxis to an agent in the penicillin class.MethodsThis was a retrospective cohort study with patients who reported “anaphylaxis” to a penicillin agent and received cefazolin, cephalexin, or aztreonam. The final analysis included 220 patients: aztreonam (n=81), cefazolin (n=81), and cephalexin (n=58) (Figure 1). IgE-mediated reactions (within six hours of antibiotic administration) were defined as any one of the following: anaphylaxis, angioedema, urticarial rash, hypotension, immediate airway compromise, or receipt of epinephrine, hydrocortisone, or diphenhydramine. Non-IgE mediated reactions (within thirty days of antibiotic administration) included delayed hypersensitivity reactions and other dermatologic reactions.Figure 1: Patient Enrollment Patients admitted between January 1, 2013 to September 1, 2020 with a reported allergy of “anaphylaxis” to an agent in the penicillin class who received at least one dose of cefazolin, cephalexin, or aztreonam were screened for inclusion. Patients were excluded if the allergy was deleted from the electronic health record prior to antibiotic administration. All first-generation cephalosporin patients were included. Aztreonam patients were included in chronological order and limited to the number of included cefazolin patients.ResultsThere were less allergic reactions in the first-generation cephalosporin group compared to the aztreonam group, but this was not statistically significant (7% vs. 14%, p=0.077). There were fewer IgE-mediated reactions in the cephalosporin group (6% vs. 14%, p=0.046). No difference in allergic reactions was observed when comparing those who received a single antibiotic dose versus multiple doses within the cephalosporin and aztreonam groups, respectively (3% vs. 11%, p=0.082, 20% vs. 12%, p=0.451). Because cephalexin has a similar R1 side chain to aminopenicillins, five patients with an aminopenicillin allergy who received cephalexin were evaluated separately; none had an allergic reaction (Table 1, Table 2, Figure 2).Table 1: Baseline Characteristics The median age was higher in the aztreonam group, and the majority of patients were female and Caucasian. There were significantly more pregnant females in the cephalosporin group, and the majority of patients reported a natural penicillin allergy.Table 2: Outcomes There were less allergic reactions (IgE or non-IgE mediated) in the first-generation cephalosporin group compared to the aztreonam group, but this was not statistically significant. Also, there were fewer IgE-mediated reactions in the cephalosporin group. There was no difference in allergic reactions in patients with two or more reported drug allergies compared to less than two drug allergies. No difference in allergic reactions was observed when comparing those who received a single antibiotic dose versus multiple doses within the cephalosporin and aztreonam groups. Of the five patients who received cephalexin and reported an aminopenicillin anaphylactic allergy, none had an allergic reaction. Additionally, there were not any patients readmitted within 30 days for delayed hypersensitivity reactions and no antibiotics were discontinued due to other documented adverse reactions.Figure 2: Occurrence of Allergic Reactions Of the patients who had allergic reactions in the cephalosporin and aztreonam groups, these included immediate airway compromise, hypotension with one patient in the aztreonam group receiving vasopressors within the pre-defined time frame, receipt of the non-standing rescue medication of diphenhydramine, and drug rash.ConclusionThere was no difference in the incidence of allergic reactions between the aztreonam and first-generation cephalosporin group, and fewer serious allergic reactions occurred in the cephalosporin group. This study suggests that cefazolin and cephalexin can safely be used in patients who report anaphylaxis to an agent in the penicillin class.Disclosures Janessa Smith, PharmD, Merck & Co. (Employee)

Pielonefritis en el anciano hospitalizado: uso de un antibiótico habitual y la adecuación a las guías

IntroductionPyelonephritis in the elderly present high incidence and morbidity-mortality. The increase in resistance makes good empirical handling essential. MethodsRetrospective observational study in people over 65 years old admitted during 2012-2017 to Palencia and Salamanca hospitals with a diagnosis of pyelonephritis. Inadequate empirical antibiotic treatment was defined if it conformed to the indications of the SEIMC Guide (2016). Results292 episodes, mean age 82±10 years, 48.3% male. Escherichia coli 53.8% and Klebsiella spp 8. 9% were the most frequently microbiological isolation found. 180 episodes (61.6%) received inadequate empirical treatment. The two most frequent causes were the use of antibiotics not included in the guidelines 107 (59.5%) and the use of 2nd-3rd generation cephalosporins in patients with risk factors for Extended spectrum betalactamases 63 (35%). Absence of identification of risk factors of extended-spectrum betalactamases was found associated to inadequate empirical antibiotic treatment (p<0,05). Inadequate treatment did not increase mortality (p>0.05). ConclusionsThe adequacy of antibiotic use in the elderly admitted for pyelonephritis according to the SEIMC Guidelines is low. The lack of identification of risk factors for betalactamases-producing Enterobacteriacea was the main factor involved. Inadequate empirical treatment was not associated with increased mortality.

1531. Antibiotic Selection for Neisseria gonorrhoeae among Penicillin Allergic Patients in the Emergency Department

BackgroundWhile penicillin (PCN) allergies are commonly reported, their cross-reactivity with beta-lactam antibiotics is minimal. First line treatment of gonorrheal infections includes a cephalosporin (CPH). In an emergency department (ED) environment, physicians must consider potential allergies when selecting antibiotics for a patient with symptoms concerning for sexually transmitted infection (STI).MethodsA retrospective chart review on adult patients with symptoms concerning for STI presenting to an urban ED from January 2014 through June 2019 was performed. Chart discovery was performed using search terms of “STI”, “STD”, “urethritis”, “vaginitis”, and “gonorrhea”. Information abstracted included patient symptoms, type of care provider, and antibiotics prescribed or administered in the ED. The primary outcome was prevalence of allergy to PCN and CPH in patients evaluated for STI symptoms and secondary outcomes included prescribed antibiotic treatments. Chi-square and Fischer-exact tests were utilized to examine for statistical significance, with p values < 0.05 as statistically significant.ResultsA total of 603 patients met the inclusion criteria, of which 31 reported allergies to PCN, and another 3 reported allergies to CPH. Patients reporting PCN allergy were found to be less likely to receive a CPH antibiotic (p=0.0035). Patients reporting a non-anaphylactic allergy to PCN received a CPH at a rate of 92.3%. Attending physicians in particular were less likely to prescribe a CPH antibiotic to a patient reporting allergy compared with both resident physicians and PAs (p=0.00019). Patients reporting a PCN allergy were more likely to receive alternative antibiotics beyond CPH or azithromycin (p=0.046); the most frequently given antibiotics were metronidazole, doxycycline, and levofloxacin.Demographic Data Antibiotic Prescriptions by Type of Penicillin Allergy Antibiotic Prescriptions for Penicillin Allergy vs. No Allergy ConclusionPatients with PCN allergies represent a recurring challenge for ED physicians when faced with antibiotic selection for STI symptoms concerning for gonorrheal infection. Those with PCN allergies are significantly less likely to receive a CPH antibiotic, though these remain the only universal treatment for gonorrheal infections. These findings highlight the significant need for further physician education on allergies and antibiotic selection.Disclosures All Authors: No reported disclosures

Is it safe to use cephalosporins in patients who are allergic to penicillin?

Is it safe to use cephalosporins in patients who are allergic to penicillin?

Cephalosporins: A Focus on Side Chains and β-Lactam Cross-Reactivity.

Cephalosporins are among the most commonly prescribed antibiotic classes due to their wide clinical utility and general tolerability, with approximately 1–3% of the population reporting a cephalosporin allergy. However, clinicians may avoid the use of cephalosporins in patients with reported penicillin allergies despite the low potential for cross-reactivity. The misdiagnosis of β-lactam allergies and misunderstanding of cross-reactivity among β-lactams, including within the cephalosporin class, often leads to use of broader spectrum antibiotics with poor safety and efficacy profiles and represents a serious obstacle for antimicrobial stewardship. Risk factors for cephalosporin allergies are broad and include female sex, advanced age, and a history of another antibiotic or penicillin allergy; however, cephalosporins are readily tolerated even among individuals with true immediate-type allergies to penicillins. Cephalosporin cross-reactivity potential is related to the structural R1 side chain, and clinicians should be cognizant of R1 side chain similarities when prescribing alternate β-lactams in allergic individuals or when new cephalosporins are brought to market. Clinicians should consider the low likelihood of true cephalosporin allergy when clinically indicated. The purpose of this review is to provide an overview of the role of cephalosporins in clinical practice, and to highlight the incidence of, risk factors for, and cross-reactivity of cephalosporins with other antibiotics.

Fatal Vitamin K-Dependent Coagulopathy Associated with Cefoperazone/Sulbactam: A Case Report.

This case report describes a suspected and fatal adverse reaction involving vitamin K-dependent coagulopathy that might be associated with cefoperazone/sulbactam (CPZ/SAM), a combined antimicrobial formulation. We reported a patient diagnosed with acute cerebral infarction and secondary pulmonary infection who was treated with an intravenous infusion of CPZ/SAM at 3 g twice daily. After receiving treatment with CPZ/SAM, the patient developed a fatal adverse reaction of CPZ-induced hemorrhage. The Naranjo assessment score in this report was 5, suggesting that the patient’s coagulation function disorder was potentially associated with the use of CPZ/SAM. To prevent vitamin K-dependent coagulopathy caused by CPZ/SAM, it is suggested to avoid cephalosporins in patients with a high risk of bleeding unless the need for cephalosporins is compelling.

Clinical impact of routine somatostatin analogues administration after pancreatoduodenectomy: a case-matched comparison according to fistula risk score, ASA and surgical technique

The aim of the present study was to investigate whether the incidence of surgical site infection after pancreatoduodenectomy decreased after changing the prophylactic antibiotic to a third-generation cephalosporin in patients with unknown preoperative bile culture results after biliary drainage.In a retrospective study of 138 pancreatoduodenectomy patients who underwent endoscopic biliary stenting and for whom recent preoperative bile culture results were unavailable, cefazolin sodium hydrate was administered as perioperative prophylactic antibiotic therapy from 2010 to 2014 (n = 69); whereas ceftriaxone was administered from 2014 to 2017 (n = 69) based on the results of institutional culture surveillance. The incidence of surgical site infection was compared between the two groups and the risk factor of surgical site infection was also evaluated.The incidence of overall surgical site infection in the ceftriaxone group was significantly lower than that in the cefazolin sodium hydrate group for both Clavien-Dindo grade ≥II (28% versus 52%, P = .005) and Clavien-Dindo grade ≥IIIa (20% vs 41%, P = .016). A multivariate analysis revealed that the prophylactic administration of cefazolin sodium hydrate was associated with a higher incidence of overall surgical site infection in both Clavien-Dindo grade ≥II and Clavien-Dindo grade ≥IIIa (odds ratio 2.56, P = .019; odds ratio 3.03, P = .020, respectively). In the cefazolin sodium hydrate group, most of the patients with positive perioperative cultures had Enterobacteriaceae, which were intrinsically resistant to cefazolin sodium hydrate, and most were susceptible to ceftriaxone.The prophylactic administration of third-generation cephalosporin reduced the incidence of surgical site infection after pancreatoduodenectomy in patients who underwent preoperative endoscopic biliary stenting.

Third-generation cephalosporin for antimicrobial prophylaxis in pancreatoduodenectomy in patients with internal preoperative biliary drainage

The aim of the present study was to investigate whether the incidence of surgical site infection after pancreatoduodenectomy decreased after changing the prophylactic antibiotic to a third-generation cephalosporin in patients with unknown preoperative bile culture results after biliary drainage. In a retrospective study of 138 pancreatoduodenectomy patients who underwent endoscopic biliary stenting and for whom recent preoperative bile culture results were unavailable, cefazolin sodium hydrate was administered as perioperative prophylactic antibiotic therapy from 2010 to 2014 (n = 69); whereas ceftriaxone was administered from 2014 to 2017 (n = 69) based on the results of institutional culture surveillance. The incidence of surgical site infection was compared between the two groups and the risk factor of surgical site infection was also evaluated. The incidence of overall surgical site infection in the ceftriaxone group was significantly lower than that in the cefazolin sodium hydrate group for both Clavien-Dindo grade ≥II (28% versus 52%, P = .005) and Clavien-Dindo grade ≥IIIa (20% vs 41%, P = .016). A multivariate analysis revealed that the prophylactic administration of cefazolin sodium hydrate was associated with a higher incidence of overall surgical site infection in both Clavien-Dindo grade ≥II and Clavien-Dindo grade ≥IIIa (odds ratio 2.56, P = .019; odds ratio 3.03, P = .020, respectively). In the cefazolin sodium hydrate group, most of the patients with positive perioperative cultures had Enterobacteriaceae, which were intrinsically resistant to cefazolin sodium hydrate, and most were susceptible to ceftriaxone. The prophylactic administration of third-generation cephalosporin reduced the incidence of surgical site infection after pancreatoduodenectomy in patients who underwent preoperative endoscopic biliary stenting.

How Safe is It to Prescribe Cephalosporins in Patients with Infectious Mononucleosis? Implications for Clinical ENT Practice.

How Safe is It to Prescribe Cephalosporins in Patients with Infectious Mononucleosis? Implications for Clinical ENT Practice.

Cross-Reactivity and Tolerability of Cephalosporins in Patients with IgE-Mediated Hypersensitivity to Penicillins

Studies performed since 1990 on samples of at least 30 subjects with a documented IgE-mediated hypersensitivity to penicillins have found a rate of positive responses to allergy tests with cephalosporins ranging from 0% to 27%. We sought to assess the cross-reactivity with cephalosporins and evaluate the possibility of using cephalosporins in penicillin-allergic subjects. We conducted a prospective study of 252 consecutive subjects who had suffered 319 immediate reactions (mostly anaphylaxis) to penicillins and had positive skin tests to at least 1 penicillin reagent. All patients underwent serum specific IgE assays for cefaclor, as well as skin tests with 3 aminocephalosporins (cephalexin, cefaclor, and cefadroxil), cefamandole, cefuroxime, ceftazidime, ceftriaxone, cefotaxime, and cefepime. Patients with negative results for the last 5 cephalosporins were challenged with cefuroxime axetil and ceftriaxone; those with negative results for aminocephalosporins were also challenged with cefaclor and cefadroxil. Ninety-nine participants (39.3%) had positive allergy tests for cephalosporins. Specifically, 95 (37.7%) were positive to aminocephalosporins and/or cefamandole, which share similar or identical side chains with penicillins. All 244 subjects who underwent challenges with cefuroxime axetil and ceftriaxone tolerated them. Of the 170 patients who underwent aminocephalosporin challenges, 3 reacted to cefaclor and 4 to cefadroxil. Cross-reactivity between penicillins and cephalosporins seems to be mainly related to side chain similarity or identity. Subjects with an IgE-mediated hypersensitivity to penicillins could be treated with cephalosporins such as cefuroxime and ceftriaxone that have side-chain determinants different from those of penicillins and are negative in pretreatment skin testing.

Cross-reactivity in β-Lactam Allergy

β-Lactam drugs (penicillins, amoxicillin, and cephalosporins) account for 42.6% of all severe drug-induced anaphylaxis. In this review, we focus on clinically significant immunologic cross-reactivity in patients with confirmed penicillin allergy to cephalosporins, and the structural involvement of the R1 and R2 chemical side chains of the cephalosporins causing IgE-mediated cross-reactivity with penicillin and other cephalosporins. Skin tests predict IgE-mediated reactions and showed cross-reactivity between penicillins and early generation cephalosporins that shared side chains, but confirmatory challenge data are lacking. Later-generation cephalosporins, which have distinct side chains, do not have any skin test cross-reactivity with penicillin/amoxicillin. There is debate as to the involvement of R2 side chains as the antigenic determinants that cause IgE-mediated hypersensitivity with various cephalosporins. Avoidance of cephalosporins, when they are the drug of choice in a penicillin-allergic individual, results in significant morbidity that outweighs the low risk of anaphylaxis. We conclude that there is ample evidence to allow the safe use of cephalosporins in patients with isolated confirmed penicillin or amoxicillin allergy.

First Place Award: Can cefazolin be used in orthopaedic surgery for patients with a self-reported non-IgE mediated penicillin allergy? A prospective case series

Background: Cefazolin is the current recommendation for antibiotic prophylaxis in orthopaedic surgery. However, reported cross-reactivity to first generation cephalosporins in patients with a penicillin allergy ranges from 4% to 18%. In their reports on the rates of cross-reactivity, previous authors have not distinguished IgE from non-IgE reactions. The purpose of this study was to determine the various reactions that are reported as a penicillin allergy and the rate of cefazolin cross-reactivity in patients having only non-IgE reactions to penicillin. Methods: This is a prospective case study of consecutive patients undergoing orthopaedic surgery that had indications for prophylactic antibiotics over a 4-year period. The patients’ self-reported specific allergic reactions to penicillin were noted. The reactions were characterized as either IgE or non-IgE mediated. Non-IgE mediated penicillin allergic patients were given cefazolin in the operating room under a controlled setting. Any adverse reaction after the administration of cefazolin was recorded. Results: There were 801 patients. The prevalence of a reported penicillin allergy was 14.1%. Non-IgE mediated reactions accounted for 73.5% of patients reporting a penicillin allergy. Of the 81 non-IgE mediated penicillin allergic patients who received cefazolin, no adverse reactions were reported. Conclusions: It is important to obtain the specific reaction in patients reporting that they are allergic to penicillin to guide the choice of antibiotics. In patients who report a non-IgE reaction to penicillin, it is safe to administer cefazolin.

Drug-Induced Hemolytic Anemia: A Fatal Complication Further Under-Recognized in Sickle Cell Disease

Drug-induced immune hemolytic anemia (DIIHA) is commonly attributed to cephalosporins. Ceftriaxone is the most frequently administered cephalosporin in patients with sickle cell disease. We present a pediatric patient with severe DIIHA (hemoglobin

Frequency of Multidrug-Resistant Organisms Cultured From Urine of Children Undergoing Clean Intermittent Catheterization.

Children undergoing CIC frequently have positive urine culture results and receive many antimicrobial agents. Subsequently, this population is at high risk for infections caused by antimicrobial-resistant bacteria. Resistant pathogens, such as vancomycin-resistant Enterococcus (VRE), carbapenem-resistant Enterobacteriaceae (CRE), and organisms that produce extended-spectrum β-lactamases (ESBLs), which are third-generation cephalosporin resistant (3GCR), are of particular concern. In this retrospective study, all urine culture results and antimicrobial-susceptibility testing results were obtained between January 2008 and December 2014 from the electronic health record of children ≤18 years of age who were undergoing CIC (n = 14 832). Isolates were identified as VRE, CRE, or 3GCR. Organisms of the same type that were obtained in the same year and with identical antibiotic susceptibilities from the same patient were excluded. Simple linear regression was used to determine the association between year and rates of resistance. A total of 3997 positive culture results were included in this analysis. Of all Enterococcus isolates for which susceptibility results were available, 4.6% were VRE, 11.1% of all isolates that belonged to the Enterobacteriaceae family were 3GCR, and 0.4% of eligible isolates were CRE. There were significantly higher rates of resistance to third-generation cephalosporins and CRE in 2014 than in 2008 (P < .01). Simple linear regression revealed a significant association between year and rate for resistance to third-generation cephalosporins but not for CRE or VRE. The rate of increase in resistance to third-generation cephalosporins in patients who required CIC was higher than that in patients who did not need CIC. The rate of resistance to third-generation cephalosporins has increased significantly in the past 7 years in children undergoing CIC, which indicates that careful monitoring is warranted for continued increases in antimicrobial-resistant organisms in this unique patient population.

Allergic rhinitis, anaphylaxis, allergic reactions: Key papers

G on treatment of allergic rhinitis and strategies to manage anaphylaxis were among several key practice parameters released in 2015. In addition, a few key papers commented on the cross-reactivity and tolerability of cephalosporins in patients who have experienced hypersensitivity reactions to these agents in the past, and on the use of live attenuated in uenza vaccine (LAIV) in those with an egg allergy. These key papers are reviewed here; for additional information, clinicians are encouraged to access the full citations.