"What if the patient has a severe reaction, and it is my fault?" A qualitative study exploring factors for sustainable implementation of penicillin allergy delabelling.

BACKGROUND: Penicillin allergy delabelling (PAD), the process of evaluating penicillin allergy labels, is a key target in antibiotic stewardship, but uptake of the procedure outside clinical studies is limited. We aimed to explore factors that need to be addressed to sustainably implement a clinical pathway for PAD. METHODS: We conducted a qualitative study based on semi-structured interviews with focus groups consisting of a purposive sample of twenty-five nurses and physicians working in four different hospitals in Western Norway. Systematic text condensation was applied for analysis. RESULTS: Psychological safety was reported as crucial for clinicians to perform PAD. A narrative of uncertainty and anticipated negative outcomes were negatively associated with PAD performance. Education, guidelines, and colleague- and leadership support could together create psychological safety and empower health personnel to perform PAD. Key factors for sustainable implementation of PAD were facilitating the informant's profound motivation for providing optimal health care and for reducing antimicrobial resistance. Informants were motivated by the prospect of a simplified PAD procedure. We identified three main needs for implementation of PAD: (1) creating psychological safety; (2) utilising clinicians' inherent motivation and (3) optimal organisational structures. CONCLUSION: A planned implementation of PAD must acknowledge clinicians' need for psychological safety and aid reassurance through training, leadership, and guidelines. To implement PAD as an everyday practice it must be minimally disruptive and provide a contextually adaptive logistic chain. Also, the clinician's motivation for providing the best possible healthcare should be utilised to aid implementation. The results of this study will aid sustainable implementation of PAD in Norway. ETHICS: The study was approved by the Western Norway Regional Committee for Medical Research Ethics (Study No:199210).

Diagnostic uncertainties in congenital syphilis: A case report.

Congenital syphilis is a forgotten disease, and often misdiagnosed. It can present with a myriad of clinical features, mimicking various other conditions therefore posing difficulty in diagnosis. Patient may be born preterm with low birth weight, failure to thrive with hemolytic anemia, thrombocytopenia, and leukocytosis. It is a treatable condition, commonly treated with penicillin or ceftriaxone.

Antepartum versus postpartum amoxicillin oral challenge in pregnant patients with a reported penicillin allergy: A two-center prospective cohort study.

INTRODUCTION: While 10% of pregnant individuals report a penicillin allergy, there is no established best practice for penicillin allergy delabeling in pregnancy. To better understand options for penicillin delabeling, we aimed to evaluate two penicillin allergy delabeling protocols in pregnancy regarding efficacy, adverse events, and patient satisfaction. MATERIAL AND METHODS: From July 2019 to December 2022, we completed a two-center prospective cohort study, where each site recruited pregnant patients over 24 weeks gestational age with a reported penicillin allergy. One center offered antepartum amoxicillin oral challenges, either directly or after negative skin testing (i.e., antepartum oral challenge site). Our other centers completed a two-step approach with antepartum penicillin skin testing only and deferred oral challenges to the postpartum period (i.e., postpartum oral challenge site). Our primary outcome was the rate of penicillin allergy delabeling, defined as tolerating an antibiotic challenge with penicillin or amoxicillin. Univariate analyses were completed using chi-squared, Fisher's exact, and Wilcoxon rank tests. RESULTS: During the study period, 276 pregnant patients were assessed, with 207 in the antepartum oral challenge site and 69 in the postpartum oral challenge site. Among the 204 patients who completed antepartum oral challenges, 201 (98%) passed without reactions. Deferring oral challenges to the postpartum period led to a loss of follow-up for 37/53 (70%) of eligible individuals. Overall, 97% (201/207) of patients at the antepartum oral challenge site were delabeled from their penicillin allergy-compared to 38% (26/69) of patients referred to the postpartum oral challenge site (p < 0.0001). Three antepartum oral challenge reactions were noted, including two mild cutaneous reactions and a case of transient abdominal discomfort. CONCLUSIONS: Antepartum amoxicillin oral challenge is a more effective method to delabel pregnant patients from their penicillin allergy. Deferral of oral challenges to the postpartum period introduces a significant barrier for penicillin allergy delabeling.

Penicillin susceptibility among Staphylococcus aureus skin and soft tissue infections at a children's hospital.

Shortly after its introduction into clinical practice, Staphylococcus aureus isolates gained resistance to penicillin via the acquisition of ß-lactamases. A number of centers have recently described an increase in the proportion of invasive methicillin-susceptible S. aureus (MSSA), which are also susceptible to penicillin (PSSA). Little data are available regarding the prevalence or impact of PSSA in skin and soft tissue infections (SSTI). Community-acquired MSSA SSTI isolates were obtained through a surveillance study at Texas Children's Hospital from January 2017 to December 2021. A total of 200 random isolates underwent PCR for blaZ ß-lactamase; blaZ-negative isolates then underwent penicillin susceptibility testing using macrobroth dilution. Isolates which were blaZ negative and had a penicillin MIC ≤0.125 µg/mL were regarded as PSSA with the remainder regarded as penicillin-resistant MSSA (PR-MSSA). All PSSA underwent multilocus sequence typing. Medical records were reviewed. The median age of subjects was 4.2 years (IQR: 1.6-10.5). PSSA accounted for 9% of isolates during the study period. PSSA and PR-MSSA cases were similar with respect to age, demographics, and rates of prior antibiotic exposure. PSSA isolates less often had vancomycin MIC ≥1.5 µg/mL. Furthermore, 39% of PSSA were variants of sequence type 1. In multivariable analyses, penicillin susceptibility was independently associated with both hospital admission and surgical intervention. PSSA account for a small but significant proportion of MSSA SSTI in children. Clinically distinguishing patients with PSSA and PR-MSSA SSTI is challenging. However, PSSA SSTI were independently associated with higher rates of hospital admission as well as the need for surgical intervention suggesting a significant clinical impact.IMPORTANCEThe vast majority of Staphylococcus aureus in the US are penicillin resistant with most clinical labs no longer reporting penicillin susceptibility for this organism. A number of centers, however, have reported increasing penicillin susceptibility among invasive S. aureus infections. Skin and soft tissue infections (SSTI) are far more common than invasive infections, yet the frequency and impact of penicillin-susceptible S. aureus (PSSA) in this population are uncertain. Through active surveillance at a children's hospital, we found that 9% of methicillin-susceptible S. aureus SSTI isolates were PSSA. PSSA were independently associated with hospital admission for the management of SSTI as well as the need for debridement in the operating room. Given that most SSTI are managed in the outpatient setting, these findings suggest a clinical impact of this phenotype and the need for a reassessment of the value in susceptibility testing and potentially even treatment with penicillin.

Soft sensing modeling of penicillin fermentation process based on local selection ensemble learning.

In the process of penicillin fermentation, there is a strong nonlinear relationship between the input eigenvector and multiple output vectors, which makes the prediction accuracy of the existing model difficult to meet the requirements of chemical production. Therefore, a local selective ensemble learning multi-objective soft sensing modeling strategy is proposed in this study. Firstly, a localization method based on transfer entropy and k-means is proposed to reconstruct the sample set. Then, based on the reconstructed local samples, the local soft sensing model is established by the multi-objective support vector regression method, and the selective ensemble of sub-models and the adaptive calculation of prediction weights are realized. At the same time, to reduce the adverse effects caused by improper selection of model parameters, the sparrow search algorithm is used to realize the tuning of the mentioned model parameters. Finally, the proposed modeling strategy is simulated. The results show that, compared with other methods, the proposed local selective ensemble learning multi-objective soft sensing modeling strategy has better prediction performance.

Penicillin binding proteins-based immunoassay for the selective and quantitative determination of beta-lactam antibiotics.

An immunoassay method based on penicillin-binding protein (PBP) was developed for the quantitative determination of 10 kinds of beta-lactam antibiotics (BLAs). First, two kinds of PBPs, which are named PBP1a and PBP2x, were expressed and purified, and they were characterized by SDS-PAGE and western blotting analysis. Then, the binding activity of PBP1a and PBP2x to template BLAs, cefquinome (CEFQ) and ampicillin (AMP), was determined. The effect of the buffer solution system, e.g., pH, ion concentration, and organic solvent, on the immune interaction efficiency between PBPs and BLAs was also evaluated. In the end, the PBP-based immunoassay method was developed and validated for the detection of 10 kinds of BLAs. Under optimal conditions, PBPs exhibited high binding affinity to BLAs. In addition, this method showed a high sensitivity for the detection of 10 kinds of BLAs with the limits of detection from 0.21 to 9.12 ng/mL, which are much lower than their corresponding maximum residual limit of European Union (4-100 ng/mL). Moreover, the developed PBP-immunoassay was employed for BLA detection from milk samples, and satisfactory recoveries (68.9-101.3 %) were obtained.

Rash decisions: Unmasking a risk phenotype in adults with persistent delayed penicillin allergy sensitized during historic infection with Epstein-Barr virus.

Background: Penicillin-associated exanthems in the setting of infectious mononucleosis caused by Epstein-Barr virus (EBV) are often viewed as a transient event, not a true allergy. Recent evidence challenges this and suggests that a notable subset of patients retain penicillin hypersensitivity. Objective: We investigated the occurrence and predictors of persistent adulthood hypersensitivity in those with penicillin-associated rash occurring in the setting of EBV infection. Methods: Retrospective analysis of data of patients referred for penicillin allergy testing to an Australian tertiary-care hospital captured from 2015 to 2023 was carried out. Results: Of 2066 patients, 23 (1%) had penicillin-associated rash during an historic EBV infection; 16 (70%) were female; and median (interquartile range) age was 18 (16-20) years at index reaction and 38 (33.5-57) years at allergy testing. Skin prick testing and delayed intradermal testing to a penicillin panel were performed, followed by oral provocation challenge in those testing negative. Persistent sensitization was shown in 6 (26%) of 23; 4 (67%) of 6 positive delayed intradermal testing; and 3 (50%) of 6 had positive oral challenge test. Notably, 5 (83%) of 6 had a severe maculopapular exanthem with facial swelling, including 2 (33%) of 6 with probable drug reaction with eosinophilia and systemic symptoms (aka DRESS) during the index reaction, compared to 0 of 17 in patients tolerating penicillin on reexposure. Conclusion: This study highlights the requirement of allergy testing in adult patients reporting a penicillin-associated severe maculopapular exanthem in the setting of EBV, even if it occurred during childhood or adolescence.

Synthesis and biochemical evaluation of new 3-amido-4-substituted monocyclic ß-lactams as inhibitors of penicillin-binding protein(s).

In the final phases of bacterial cell wall synthesis, penicillin-binding proteins (PBPs) catalyze the cross-linking of peptidoglycan. For many decades, effective and non-toxic ß-lactam antibiotics have been successfully used as mimetics of the d-Ala-d-Ala moiety of the natural substrate and employed as irreversible inhibitors of PBPs. In the years following their discovery, the emergence of resistant bacteria led to a decline in their clinical efficacy. Using Staudinger cycloaddition, we synthesized a focused library of novel monocyclic ß-lactams in which different substituents were introduced at the C4 position of the ß-lactam ring, at the C3 amino position, and at the N1 lactam nitrogen. In biochemical assays, the compounds were evaluated for their inhibitory effect on the model enzyme PBP1b from Streptococcus pneumoniae. Upon investigation of the antibacterial activity of the newly prepared compounds against ESKAPE pathogens, some compounds showed moderate inhibition. We also examined their reactivity and selectivity in a biochemical assay with other enzymes that have a catalytic serine in the active site, such as human cholinesterases, where they also showed no inhibitory activity, highlighting their specificity for bacterial targets. These compounds form the basis for further work on new monocyclic ß-lactams with improved antibacterial activity.

Penicillin allergy delabeling has a significant impact on subsequent antibiotic use in primary care.

Efforts to delabel penicillin allergic patients are important as the majority of suspected penicillin allergy can be ruled out by relevant allergy testing. The aim is to change the antibiotic pattern in delabeled patients to minimize use of unnecessary broad-spectrum antibiotics, reducing the risk of antimicrobial resistance and making treatment more cost effective. However, published information on subsequent antibiotic use is scarce. To evaluate the effect of delabeling on subsequent antibiotic use in primary care, a cohort of 2911 patients tested for penicillin allergy was compared to a matched control group of 14,522 individuals from the background population. In total 86.4% of the tested patients were delabeled. For delabeled patients, penicillin use increased from 0.07 prescriptions per patient year before allergy investigation, to 0.53 prescriptions per patient year post investigation (p < 0.001). The use of fluoroquinolones and macrolides was reduced and reached a level comparable to the background population. This study shows that penicillin allergy delabeling has significant positive impact on subsequent antibiotic use in primary care, and that penicillin use increases to levels similar to the background population. Penicillin allergy delabeling should be prioritized as an important and efficient element in antimicrobial stewardship initiatives.

Phenotypic and genotypic characterization of methicillin resistant Staphylococcus aureus associated with pyogenic infections.

Background and Objectives: Staphylococcal infections are one of the major infectious diseases affecting globally in spite of advances in development of antimicrobial agents. Knowledge and awareness about the local pattern and prevalence of MRSA infections plays a key role in treatment. The aim of this study was to identify MRSA strains by phenotypic and genotypic methods and to analyze the antibiotic susceptibility pattern of MRSA strains from patients attending a tertiary care hospital. Materials and Methods: This study was conducted over a period of 1 year, where 296 isolates of Staphylococcus aureus were isolated from various clinical specimens. The isolated strains were examined for antibiotic susceptibility by the modified Kirby Bauer disc diffusion method. Methicillin resistance was detected by cefoxitin disk diffusion test. Results: A total of 104 isolates were found to be MRSA and 192 were found to be MSSA. Among the 104 MRSA isolates, 10 strains that were multidrug resistant were subjected to 16S rRNA gene sequencing analysis. All the 10 strains had a 99% match with S. aureus strains that were responsible for causing some serious biofilm mediated clinical manifestations like cystic fibrosis and device mediated infections. The biofilms were quantified using crystal violet staining and their ability to produce biofilms was analyzed using scanning electron microscopy and matched with the Genbank. Conclusion: Hence these phylogenetic analysis aid in treating the patients and combating resistance to antibiotics.

Peptidoglycan Endopeptidase PBP7 Facilitates the Recruitment of FtsN to the Divisome and Promotes Peptidoglycan Synthesis in Escherichia coli.

Escherichia coli has many periplasmic hydrolases to degrade and modify peptidoglycan (PG). However, the redundancy of eight PG endopeptidases makes it challenging to define specific roles to individual enzymes. Therefore, the cellular role of PBP7 (encoded by pbpG) is not clearly defined. In this work, we show that PBP7 localizes in the lateral cell envelope and at midcell. The C-terminal α-helix of PBP7 is crucial for midcell localization but not for its activity, which is dispensable for this localization. Additionally, midcell localization of PBP7 relies on the assembly of FtsZ up to FtsN in the divisome, and on the activity of PBP3. PBP7 was found to affect the assembly timing of FtsZ and FtsN in the divisome. The absence of PBP7 slows down the assembly of FtsN at midcell. The ΔpbpG mutant exhibited a weaker incorporation of the fluorescent D-amino acid HADA, reporting on transpeptidase activity, compared to wild-type cells. This could indicate reduced PG synthesis at the septum of the ΔpbpG strain, explaining the slower accumulation of FtsN and suggesting that endopeptidase-mediated PG cleavage may be a rate-limiting step for septal PG synthesis.

Bibliometric analysis of the trends and evolution in ß-lactam allergy research.

Background: ß-Lactams remain the most reported drug allergy globally, with the volume and diversity of related drug allergy research continuing to accumulate. Recognizing evolving research trends can help inform future directions and encourage synergistic collaborations. Objective: We conducted a comprehensive bibliometric analysis of all publications relevant to ß-lactam allergy, with a focus on longitudinal publication rates, international collaborations, and key word/trend analysis. Methods: Meta-data from all original articles, letters, and reviews relevant to ß-lactam allergy on the Web of Science Core Collection up until December 31, 2023, were analyzed. Results: From 1966 to 2023, there were 4451 records (3536 articles, 631 reviews, and 284 letters) from 78 countries. There was an exponential increase in publications, especially during the past decade, with half of all publications on ß-lactam allergy published during this time (50.6% [2252 of 4452]). Overall, 18.1% of the publications (805 of 4452) involved international coauthorships, with a significant increase since the previous decade (12.7% vs 23.3% [P < .001]). The most frequent key words in the first published half of articles were skin testing (84 of 1919), IgE (57 of 1919), and anaphylaxis (49 of 1919); in contrast to the key word skin testing (137 of 3351), the key words drug provocation test (121 of 3351), antimicrobial resistance (120 of 3351), and antimicrobial stewardship (118 of 3351) were the most frequent key words in the latter half. Conclusion: There has been a surge in publications, international collaboration, and shifting paradigms in ß-lactam allergy research. The field has evolved beyond focusing on in vitro tests or desensitization toward antimicrobial stewardship. However, there still seems to be relatively fewer collaborations with non-Western countries. Further international collaborations to harmonize delabeling strategies against the threat of mislabeled ß-lactam allergy should be encouraged.

Management of Tubo-Ovarian Abscess in a Patient With Factor V Leiden Deficiency and High Body Mass Index (BMI).

This case report details the clinical course, diagnostic challenges, and management of a 53-year-old female patient with a history of factor V Leiden deficiency, hypertension, and high body mass index (BMI), presenting with an acute tubo-ovarian abscess (TOA). The patient's medical history also included penicillin allergy, premenopausal bleeding, and two previous cesarean sections, adding complexity to her management. Upon presentation, the patient exhibited symptoms of TOA, a severe complication of pelvic inflammatory disease (PID). Given her high BMI and surgical history, the risks associated with surgical intervention were significant. Consequently, a conservative approach with prolonged antibiotic therapy was chosen. The diagnosis was supported by initial and follow-up CT scans, which revealed multiple fluid collections indicative of infection but did not suggest a safe access route for percutaneous drainage. The patient's penicillin allergy required a careful selection of antibiotics to ensure efficacy and avoid adverse reactions. A multidisciplinary team comprising specialists from gynecology, microbiology, and radiology collaborated to devise and implement an effective treatment plan. This approach allowed for regular reassessment and adjustments to the therapeutic regimen. The patient received broad-spectrum antibiotics tailored to her specific needs, with the regimen prolonged due to the infection's severity and the high risk of surgical complications. The patient's inflammatory markers, including C-reactive protein (CRP) levels, were closely monitored, guiding treatment adjustments. Over time, significant clinical improvement was observed, with a gradual decrease in CRP levels and symptom resolution. This case underscores the importance of a tailored, patient-specific approach in managing complex TOA cases. It highlights the potential for conservative management with antibiotics in high-risk patients where surgical intervention poses significant risks. The successful outcome emphasizes the value of a multidisciplinary approach and individualized care in achieving favorable outcomes in TOA management.

The Interactions of Resveratrol and Sodium Valproate on Penicillin-Induced Epilepsy Model: Electrophysiological and Molecular Study.

Epilepsy represents the most prevalent chronic neurological disease, characterized by spontaneous recurrent seizures. In experimental epilepsy models created by different methods, resveratrol has been demonstrated to reduce epileptiform activity and exhibit neuroprotective properties. A penicillin-induced model of epileptogenesis was used to investigate the effects of resveratrol and its combination with sodium valproate on epileptiform activity. The study design was an in vivo animal experimental study. Forty Wistar-albino rats were divided into five groups, each with eight rats. The groups are categorized as the saline group, penicillin group (only penicillin), resveratrol group, sodium valproate group, and resveratrol + sodium valproate group. ECoG recording was taken for 180 min in all groups and statistically evaluated. GABAα1, mGluR1/mGluR5, NMDAR1 receptor expressions in the hippocampus, and S100B level in serum were measured. The spike frequency decreased statistically to 60th min in the sodium valproate group and 150th min in the resveratrol group. The spike frequency decreased statistically in the 20th min and later measurements of the recording in the resveratrol + sodium valproate group. GABAα1 receptor expression was increased in all groups compared to the penicillin group. mGluR1/mGluR5, NMDAR1 receptor expression was decreased in all groups compared to the penicillin group. Serum S100B level increased in all groups compared to the penicillin group. There was no statistically significant difference in epileptiform activity when resveratrol alone was administered in the penicillin-induced epilepsy model. Resveratrol co-administered with sodium valproate significantly reduced epileptiform activity. Co-administration of the sodium valproate + resveratrol group made the receptor level's highest GABAα1receptor expression at receptors.

Visible-light-driven peroxydisulfate activation by biochar-loaded Fe-Cu layered double hydroxide for penicillin G degradation: Performance, mechanism and application potential.

The biochar-loaded Fe-Cu layered double hydroxide (FeCu-LDH@BC) catalyst was synthesized via a simple hydrothermal method and used to activate peroxydisulfate (PDS) for penicillin G (PG) degradation under visible light. The physicochemical properties of FeCu-LDH@BC were characterized using SEM, XPS, UV-DRS, SEM-EDS, HRTEM, XRD, BET, PL spectrum, FT-IR, Raman spectrum, TG-DSC, TPD, and EIS, showing that biochar (BC) enhanced the optical properties of FeCu-LDH. Notably, the FeCu-LDH@BC + PDS + Light system achieved a 98.79% degradation efficiency for PG in just 10 min. Furthermore, FeCu-LDH@BC retained excellent activity after four reuse cycles. LSV results indicated enhanced electron transfer in the FeCu-LDH@BC + PDS + Light system, suggesting a synergistic effect between the photocatalytic and PDS activation systems. The interconversion of h+, SO4·â», 1O2, and ·OH species was found to play a key role in PG degradation. Density functional theory was used to identify PG sites susceptible to radical attack, and the possible degradation pathway was proposed based on liquid chromatography-mass spectrometry results. Toxicity evaluation using the TEST software confirmed that the intermediates formed were significantly less toxic than PG. Lastly, the FeCu-LDH@BC + PDS + Light system removed 37.45% of total organic carbon and 63.74% of chemical oxygen demand from real wastewater within 120 min. The type and transformation pathways of organic matter in the wastewater were analyzed using 3D Excitation Emission Matrix spectroscopy to assess the system's application potential.

Preadmission Penicillin Allergy Evaluation Before Hematopoietic Stem Cell Transplantation Optimizes Febrile Neutropenia Treatment and Inpatient Resource Utilization.

Febrile neutropenia is a common complication of conditioning chemotherapy for hematopoietic stem cell transplant (HSCT), but a major barrier for optimal treatment of febrile neutropenia is historical penicillin allergies. Our group recently published a development of a clinical pipeline for delabeling penicillin allergies in adult patients planned to undergo hematopoietic stem cell transplant (HSCT). In this retrospective cohort study, we followed patients to evaluate their outcomes during inpatient admission for HSCT. We hypothesized that, among patients planned for HSCT with a self-reported penicillin allergy, completing penicillin allergy testing (amoxicillin ingestion challenge with or without concomitant penicillin skin testing) prior to HSCT admission would be associated with differences in inpatient treatment for febrile neutropenia (including antibiotic selection and timing of antibiotic administration) and improved inpatient resource utilization (including nursing and inpatient physician consults). We identified patients with a self-reported penicillin allergy who answered a penicillin allergy questionnaire and were subsequently admitted to our institution for HSCT. We divided the cohort into 2 groups: patients whose penicillin allergy was evaluated prior to admission (EPTA) and patients whose penicillin allergy was not evaluated prior to admission (NEPTA). We then performed comparison between the 2 groups for general clinical outcomes of HSCT admission (duration of admission, need for ICU transfer, readmission rate, etc.), febrile neutropenia treatment, and inpatient resource utilization. Statistics were calculated using the nonparametric 2-tailed Fisher exact test for categorical outcomes and the nonparametric 2-tailed Mann-Whitney U test for numerical outcomes. Within our cohort, 35 patients completed penicillin allergy testing prior to HSCT admission (EPTA) and 44 patients did not (NEPTA). Demographics were similar between these groups, and there was no significant difference in the rate of febrile neutropenia during HSCT admission (EPTA 64% versus NEPTA 66%, P = 1.00). EPTA patients were significantly more likely to receive standard first-line antibiotics (cefepime or ceftazidime) for febrile neutropenia (EPTA 95% versus NEPTA 65%, P = .015) and time between febrile neutropenia onset and antibiotic administration was shorter (EPTA mean 66 mins versus NEPTA mean 121 mins, P = .0058). No patients in the EPTA group experienced an immediate hypersensitivity reaction (hives, anaphylaxis, etc.) or severe cutaneous adverse reaction (SCAR) during HSCT admission. EPTA patients were also significantly less likely to require 1:1 nursing for antibiotic test doses, challenges, and desensitizations (EPTA 0% versus NEPTA 49%, P < .0001); less likely to require inpatient allergy consult (EPTA 0% versus NEPTA 12%, P = .031); and less likely to require inpatient antimicrobial stewardship consult (EPTA 0% versus NEPTA 13%, P = .013) during their HSCT admission. In summary, patients who completed penicillin allergy testing prior to HSCT admission were more likely to receive first-line antibiotics and received antibiotics more rapidly for treatment of febrile neutropenia. Furthermore, patients who completed penicillin allergy testing prior to HSCT admission were less likely to require 1:1 nursing, inpatient allergy consults, and inpatient antimicrobial stewardship consults during HSCT admission.

The effect of benzylpenicillin prohylaxis after birth on length and weight of syphilis-exposed infants in eastern China.

BACKGROUND: We conducted this study to assess the impact of an intervention to interrupt mother-to-child transmission on the height and weight of syphilis-exposed infants after receiving penicillin prophylaxis after birth and to provide a scientific basis for further elimination of mother-to-child transmission. METHODS: We recruited 419 infants born to syphilis-infected mothers from 2015 to 2020 in Changzhou, and performed 1:1 matching to infants born to syphilis-free mothers during the same period. All infants were followed up to 18 months of age. We collected height and weight data and compared them. RESULTS: At 18 months of age, the height and weight of the syphilis-exposed infants were almost greater than the WHO reference standards. However, when compared with local unexposed infants, there were almost no differences. The boys born to mothers who received two courses of treatment had longer body lengths at 18 months of age than did those born to mothers who did not receive two courses of treatment, and the girls born to mothers who did not receive treatment had lower body weights at 3 months of age than did both treated groups. CONCLUSION: The growth trajectory of infants without congenital syphilis born to syphilis-infected mothers is virtually indistinguishable from that of the general local population. Syphilis-exposed newborns can receive preventive treatment as a public health intervention.

The physiological role of Acinetobacter baumannii DacC is exerted through influencing cell shape, biofilm formation, the fitness of survival and manifesting DD-carboxypeptidase and beta-lactamase dual-enzyme activities.

With the growing threat of drug-resistant Acinetobacter baumannii, there is an urgent need to comprehensively understand the physiology of this nosocomial pathogen. As penicillin-binding proteins are attractive targets for antibacterial therapy, we have tried to explore the physiological roles of two putative DD-carboxypeptidases, viz., DacC and DacD, in A. baumannii. Surprisingly, the deletion of dacC resulted in a reduced growth rate, loss of rod-shaped morphology, reduction in biofilm-forming ability, and enhanced susceptibility towards beta-lactams. In contrast, the deletion of dacD had no such effect. Interestingly, ectopic expression of dacC restored the lost phenotypes. The ∆dacCD mutant showed properties similar to the ∆dacC mutant. Conversely, in vitro enzyme kinetics assessments reveal that DacD is a stronger DD-CPase than DacC. Finally, we conclude that DacC might have DD-CPase and beta-lactamase activities, whereas DacD is a strong DD-CPase.

Not a Benign (Mis)Label: Penicillin Allergy Education for the Nonallergist.

Introduction: Up to 20% of the US population carries a penicillin allergy label; however, over 95% of those patients can safely tolerate penicillin. This discrepancy has important personal and public health consequences. There is no published curriculum for medical trainees that covers penicillin allergy history taking, risk assessment, and antibiotic prescribing. Methods: We created a 60-minute, interactive curriculum that targeted medical students during their internal medicine rotation. We employed learning strategies including didactics, case-based learning, and role-playing. We compared self-efficacy and knowledge before and after the intervention using paired t tests. Results: A total of 28 medical students participated, with 25 completing both the pre- and postworkshop surveys. There was a statistically significant improvement in student-rated preparedness to prescribe antibiotics to patients with a penicillin allergy label (p < .001) and determine whether a patient has a history of an allergic reaction that was severe or life-threatening (p < .001). There was additionally a statistically significant increase in students' perception that penicillin allergy labels carry important health consequences (p = .005), as well as increase in their total knowledge scores (p = .006). Discussion: The workshop employs adult learning techniques to improve self-efficacy and knowledge regarding penicillin allergy in medical students. Further work is needed to refine the curriculum, seek external validity, and determine the impact of this workshop on clinical outcomes.

Screening and Selection of Antibiotics for Enhanced Production of Astaxanthin by Haematococcus lacustris.

Haematococcus lacustris (Girod-Chantrans) Rostafinski (Chlorophyta) is the richest microalgal source of astaxanthin. Natural astaxanthin from H. lacustris has been widely studied and used for commercial production worldwide. In this study, we examined the effects of 11 antibiotics (dihydrostreptomycin sulphate, neomycin, chloramphenicol, penicillin, streptomycin, ampicillin, kanamycin, gentamycin, hygromycin B, tetracycline, and paromomycin) on the biomass dry weight, growth, and astaxanthin yield of H. lacustris using Jaworski's medium without a nitrogen source. Astaxanthin content in H. lacustris was improved in the presence of ampicillin (0.25 g/L, 0.5 g/L, 1 g/L), chloramphenicol (0.25 g/L), and penicillin (0.25 g/L, 0.5 g/L, 1 g/L) in comparison to the control on day 15. The greatest increase in astaxanthin content on day 15 (6.69-fold) was obtained with the addition of penicillin (0.5 g/L) in comparison to the control. Similarly, on day 15, the cell numbers were also the highest for the H. lacustris culture grown with the addition of penicillin (0.5 g/L).