Syphilis presenting as optic neuritis and subdural haematoma with complicating neuro Jarisch-Herxheimer reaction.

A man in his 50s presented with a 3-week history of painless blurry vision. The ocular examination showed decreased visual acuity and 3+ bilateral papilloedema. A CT of the brain without contrast revealed a 5 mm left subdural haematoma. Anti-treponemal IgG antibodies were positive, and a reflex rapid plasma regain (RPR) was >1:64. HIV serology was negative. Ophthalmology and infectious diseases agreed that the presentation was consistent with ocular syphilis. Cerebrospinal fluid (CSF) examination revealed an elevated CSF protein of 52 mg/dL and CSF Venereal Disease Research Laboratory (VDRL) of 1:1. Penicillin was started. The patient developed a Jarisch-Herxheimer reaction soon after. He had a fever, rash and worsening headaches due to the enlargement of subdural haematoma for which he underwent a burr hole drainage. Vision improved after completing penicillin therapy but did not recover fully. The CSF VDRL became non-reactive and serum RPR titre decreased to 1:8 3 months later.

Analysis of dissolved organic matter characteristics in pharmaceutical wastewater via spectroscopy combined with Fourier-transform ion cyclotron resonance mass spectrometry.

Studying the changes in organic matter and characteristic pollutants during the treatment of penicillin-containing pharmaceutical wastewater, which can be reflected by changes in dissolved organic matter (DOM), is crucial for improving the effectiveness of wastewater treatment units and systems. Herein, water quality indicators, spectroscopic methods, and Fourier-transform ion cyclotron resonance mass spectrometry were utilized to characterize the general molecular compositions and specific molecular changes in DOM during the treatment of typical penicillin-containing pharmaceutical wastewater, including in each of the influent, physicochemical treatment, biological treatment, oxidation treatment, and effluent stages. The influent exhibited a high organic matter content (concentration of dissolved organic carbon >10,000 mg·L-1), its DOM mainly contained protein- and lignin-like substances composed of CHON and CHONS molecules, and the relative intensity (RI) of penicillin was extremely high (RI = 0.220). Compared with the influent, the abundance of CHON and CHONS molecules detected after physicochemical treatment decreased by 70.3 % and 62.5 %, respectively, and the RI of penicillin decreased by 85.5 %. Biological treatment caused substantial changes in DOM components through oxidation, dealkylation, and denitrification reactions, accounting for 36.8 %, 28.9 %, and 14.8 % of the total identified reactions, respectively. Additionally, lignin-like substances were generated in large quantities, the overall humification level significantly increased, and the RI value increased for the penicillin intermediate, 6-aminopenicillanic acid (6-APA). Oxidation treatment effectively removed phosphorus-containing substances and some lignin-like substances produced by biological treatment; however, it was not effective in removing characteristic pollutants such as 6-APA. Such characteristic substances continued to be present in the effluent, and the DOM mainly contained protein- and humus-like substances, accounting for 30.8 % and 47.3 %, respectively. The study findings reveal the changes in organic matter and characteristic pollutants during the treatment of penicillin-containing wastewater from the perspective of the general molecular composition and specific molecular changes in DOM, providing support for further exploration of wastewater treatment mechanisms and improvements in treatment unit efficiency.

Antibiotic susceptibility of orofacial infections in Bratislava: a 10-year retrospective study.

OBJECTIVES: Aim of this study was to analyse causal microbiological agents and their bacterial resistance in orofacial infections requiring hospital admission. MATERIALS AND METHODS: Presented is a 10-year retrospective study of patients hospitalised at a single department in 2014-2023. 744 patients were involved. In the statistical analysis, following data was evaluated: causal microbes and their resistance to Penicillin, Amoxicillin-Clavulanate, Clindamycin and Metronidazole. RESULTS: Most frequent aetiology was odontogenic with causal tooth in socket (n = 468; 62,9%), followed by odontogenic - post extraction (n = 152; 20.4%), jaw fracture (n = 41; 5.5%), sialadenitis n = 31 (4.2%), osteonecrosis n = 22 (3.0%), oncological diagnosis in head and neck (n = 17; 2.3%), unknown (n = 10; 1.3%) and multiple factors (n = 3; 0.4%). 408 patients (54.8%) underwent extraoral abscess revision, 336 patients (45.2%) patients were treated locally without extraoral revision. In odontogenic group with tooth still present, superior CRP (m = 145.8 mg/l; SD = 117.7) and leukocyte values (m = 13.6*109l; SD = 6.6) were observed in comparison to other groups. There were 698 cultivated bacteria in 362 patients. Most frequent bacteria were Streptococci (n = 162; 23.2%), Prevotella (n = 83; 11.2%) and Parvimonas (n = 65; 9.3%). Clindamycin resistance was highest (n = 180 resistant bacteria; 25.8%), followed by Metronidazole (n = 178; 25.5%), Penicillin (n = 107; 15.3%) and Amoxicillin-Clavulanate (n = 34; 4.9%). CONCLUSIONS: Orofacial infections in head and neck region are mostly of odontogenic origin with causal tooth still in socket. Causal bacteria show a high antibiotic resistance rate, especially to Clindamycin and Metronidazole. CLINICAL RELEVANCE: Acquired data will be used to determine guidelines for empirical antibiotic prescription in cases of orofacial infections.

Factors influencing implementation and adoption of direct oral penicillin challenge for allergy delabelling: a qualitative evaluation.

BACKGROUND: Over 95% of penicillin allergy labels are inaccurate and may be addressed in low-risk patients using direct oral penicillin challenge (DPC). This study explored the behaviour, attitudes and acceptability of patients, healthcare professionals (HCPs) and managers of using DPC in low-risk patients. METHODS: Mixed-method, investigation involving patient interviews and staff focus groups at three NHS acute hospitals. Transcripts were coded using inductive and deductive thematic analysis informed by the Theoretical Domains Framework. FINDINGS: Analysis of 43 patient interviews and three focus groups (28 HCPs: clinicians and managers) highlighted themes of 'knowledge', 'beliefs about capabilities and consequences', 'environmental context', 'resources', 'social influences', 'professional role and identity', 'behavioural regulation and reinforcement' and a cross-cutting theme of digital systems. Overall, study participants supported the DPC intervention. Patients expressed reassurance about being in a monitored, hospital setting. HCPs acknowledged the need for robust governance structures for ensuring clarity of roles and responsibilities and confidence. CONCLUSION: There were high levels of acceptability among patients and HCPs. HCPs recognised the importance of DPC. Complexities of penicillin allergy (de)labelling were highlighted, and issues of knowledge, risk, governance and workforce were identified as key determinants. These should be considered in future planning and adoption strategies for DPC.

Long-term antibiotic prophylaxis for prevention of rheumatic fever recurrence and progression to rheumatic heart disease.

BACKGROUND: Rheumatic fever is a non-suppurative, inflammatory sequela of group A Streptococcus pharyngitis that can occur at two to four weeks after infection. Following an episode of rheumatic fever, there is a risk of developing rheumatic heart disease (RHD) later in life that carries significant risk of morbidity and mortality. RHD remains the largest global cause of cardiovascular disease in the young (age < 25 years). The historical literature provides inconclusive evidence that antibiotic prophylaxis is beneficial in reducing the risk of recurrence of rheumatic fever and development of RHD. Antibiotics are thought to work by reducing the carriage of group A Streptococcus and thus reducing the risk of infection. This review was commissioned by the World Health Organization (WHO) for an upcoming guideline. OBJECTIVES: 1. To assess the effects of long-term antibiotics versus no antibiotics (control) for secondary prevention of rheumatic fever recurrence and associated sequelae in people with previous rheumatic fever or RHD. 2. To assess the effects of long-term intramuscular penicillin versus long-term oral antibiotics for secondary prevention of rheumatic fever recurrence and associated sequelae in people with previous rheumatic fever or RHD. SEARCH METHODS: We systematically searched CENTRAL, MEDLINE, Embase, Conference Proceedings Citation Index-Science, clinical trial registers, ISRCTN.com and reference lists without restrictions on language or date up to 10 March 2024. SELECTION CRITERIA: We sought randomised controlled trials or quasi-randomised trials, described in any language, including participants with previous rheumatic fever and/or RHD of any age, based in community or hospital settings. Studies were included if they compared firstly antibiotic prophylaxis with no antibiotic prophylaxis, and, secondly, intramuscular penicillin prophylaxis versus oral antibiotic prophylaxis. DATA COLLECTION AND ANALYSIS: We used standardised methodological, Cochrane-endorsed procedures and performed meta-analyses with risk ratios (RR) and Peto odds ratios (Peto OR). Our primary outcomes were recurrence of rheumatic fever, progression or severity of RHD and cardiac complications. Our secondary outcomes were obstetric complications (maternal and foetal events), mortality, treatment adherence, adverse events and acceptability to participants. We performed comprehensive assessments of risk of bias and certainty of evidence, applying the GRADE methodology. MAIN RESULTS: We included 11 studies (seven RCTs and four quasi-randomised trials) including 3951 participants. The majority of the included studies were conducted in the USA, UK and Canada during the 1950s to 1960s. Most participants with previous rheumatic fever had been diagnosed using the modified Jones criteria (mJC) (four studies), were an average of 12.3 years of age and 50.6% male. We assessed the majority of the included studies to be at high risk of bias, predominantly relating to blinding and attrition bias. Comparison one: antibiotics versus no antibiotics Pooled meta-analysis of six RCTs provides moderate-certainty evidence that antibiotics overall (oral or intramuscular) probably reduce the risk of recurrence of rheumatic fever substantially (0.7% versus 1.7%, respectively) (risk ratio (RR) 0.39, 95% confidence interval (CI) 0.22 to 0.69; 1721 participants). People with early or mild RHD likely have the greatest capacity to benefit from intramuscular antibiotic prophylaxis (8.1%) compared to no antibiotics (0.7%) (RR 0.09, 95% CI 0.03 to 0.29; 1 study, 818 participants; moderate-certainty evidence). Antibiotics may not affect mortality in people with late-stage RHD (RR 1.23, 95% CI 0.78 to 1.94; 1 study, 994 participants; low-certainty evidence). Antibiotics may not affect the risk of anaphylaxis (Peto odds ratio (OR) 7.39, 95% CI 0.15 to 372; 1 study, 818 participants; low-certainty evidence) or sciatic nerve injury (Peto OR 7.39, 95% CI 0.15 to 372; 1 study, 818 participants; low-certainty evidence) compared with no antibiotics, but probably have an increased risk of hypersensitivity reactions (RR 137, 8.51 to 2210; 2 studies, 894 participants; moderate-certainty evidence) and local reactions (RR 29, 1.74 to 485; 1 study, 818 participants; moderate-certainty evidence). Comparison two: intramuscular antibiotics versus oral antibiotics Pooled analysis of two RCTs showed that prophylactic intramuscular benzathine benzylpenicillin likely reduces recurrence of rheumatic fever substantially when compared to oral antibiotics (0.1% versus 1%, respectively) (RR 0.07, 95% CI 0.02 to 0.26; 395 participants; moderate-certainty evidence). Furthermore, it is unclear whether intramuscular benzyl penicillin is superior to oral antibiotics in reducing the risk of mortality in the context of RHD (Peto OR 0.22, 95% CI 0.01 to 4.12; 1 study, 431 participants; very low-certainty evidence). There were no data available on progression of latent RHD or adverse events including anaphylaxis, sciatic nerve injury, delayed hypersensitivity/allergic reactions and local reactions to injection. AUTHORS' CONCLUSIONS: This review provides evidence that antibiotic prophylaxis likely reduces the risk of recurrence of rheumatic fever compared to no antibiotics, and that intramuscular benzathine benzylpenicillin is probably superior to oral antibiotics (approximately 10 times better). Moreover, intramuscular benzathine benzylpenicillin likely reduces the risk of progression of latent RHD. Evidence is scarce, but antibiotics compared with no antibiotics may not affect the risk of anaphylaxis or sciatic nerve injury, but probably carry an increased risk of hypersensitivity reactions and local reactions. Antibiotics may not affect all-cause mortality in late-stage RHD compared to no antibiotics. There is no evidence available to comment on the effect of intramuscular penicillin over oral antibiotics for progression of latent RHD and adverse events, and little evidence for all-cause mortality. It is important to interpret these findings in the context of major limitations, including the following: the vast majority of the included studies were conducted more than 50 years ago, many before contemporary echocardiographic studies; methodology was often at high risk of bias; outdated treatments were used; only one study was in latent RHD; and there are concerns regarding generalisability to low socioeconomic regions. This underlines the need for ongoing research to understand who benefits most from prophylaxis.

"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).

Genomic analysis of two penicillin- and rifampin-resistant Corynebacterium rouxii strains isolated from cutaneous infections in dogs.

Although diphtheria is a vaccine-preventable disease, numerous cases are still reported around the world, as well as outbreaks in countries, including European ones. Species of the Corynebacterium diphtheriae complex are potentially toxigenic and, therefore, must be considered given the possible consequences, such as the circulation of clones and transmission of antimicrobial resistance and virulence genes. Recently, Corynebacterium rouxii was characterized and included among the valid species of the complex. Therefore, two cases of C. rouxii infection arising from infections in domestic animals are presented here. We provide molecular characterization, phylogenetic analyses, genome sequencing, and CRISPR-Cas analyses to contribute to a better understanding of the molecular bases, pathogenesis, and epidemiological monitoring of this species, which is still little studied. We confirmed its taxonomic position with genome sequencing and in silico analysis and identified the ST-918 for both strains. The clinical isolates were sensitive resistance to benzylpenicillin and rifampin. Antimicrobial resistance genes, including tetB, rpoB2, and rbpA genes, were predicted. The bla and ampC genes were not found. Several virulence factors were also detected, including adhesion, iron uptake systems, gene regulation (dtxR), and post-translational modification (MdbA). Finally, one prophage and the Type I-E CRISPR-Cas system were identified.

Oral Antibiotics and Risk of Serious Cutaneous Adverse Drug Reactions.

Importance: Serious cutaneous adverse drug reactions (cADRs) are potentially life-threatening drug hypersensitivity reactions involving the skin and internal organs. Antibiotics are a recognized cause of these reactions, but no studies have compared relative risks across antibiotic classes. Objectives: To explore the risk of serious cADRs associated with commonly prescribed oral antibiotics, and to characterize outcomes of patients hospitalized for them. Design, Setting, and Participants: Nested case-control study using population-based linked administrative datasets among adults aged 66 years or older who received at least 1 oral antibiotic between 2002 and 2022 in Ontario, Canada. Cases were those who had an emergency department (ED) visit or hospitalization for serious cADRs within 60 days of the prescription, and each case was matched with up to 4 controls who did not. Exposure: Various classes of oral antibiotics. Main Outcomes and Measures: Conditional logistic regression estimate of the association between different classes of oral antibiotics and serious cADRs, using macrolides as the reference group. Results: During the 20-year study period, we identified 21 758 older adults (median age, 75 years; 64.1% female) who had an ED visit or hospitalization for serious cADRs following antibiotic therapy and 87 025 matched controls who did not. In the primary analysis, sulfonamide antibiotics (adjusted odds ratio [aOR], 2.9; 95% CI, 2.7-3.1) and cephalosporins (aOR, 2.6; 95% CI, 2.5-2.8) were most strongly associated with serious cADRs relative to macrolides. Additional associations were evident with nitrofurantoin (aOR, 2.2; 95% CI, 2.1-2.4), penicillins (aOR, 1.4; 95% CI, 1.3-1.5), and fluoroquinolones (aOR, 1.3; 95% CI, 1.2-1.4). The crude rate of ED visits or hospitalization for cADRs was highest for cephalosporins (4.92 per 1000 prescriptions; 95% CI, 4.86-4.99) and sulfonamide antibiotics (3.22 per 1000 prescriptions; 95% CI, 3.15-3.28). Among the 2852 case patients hospitalized for cADRs, the median length of stay was 6 days (IQR, 3-13 days), 9.6% required transfer to a critical care unit, and 5.3% died in the hospital. Conclusion and Relevance: Commonly prescribed oral antibiotics are associated with an increased risk of serious cADRs compared with macrolides, with sulfonamides and cephalosporins carrying the highest risk. Prescribers should preferentially use lower-risk antibiotics when clinically appropriate.

[The Soviet-Chinese cooperation in production of penicillin in the 1950s].

The article considers, on the basis of analysis of archival documents, issue of Soviet-Chinese cooperation in field of production of penicillin in the 1950s. The main attention is paid to history of construction of penicillin plant in Shijiazhuang. It is demonstrated that it was carried out on preferential terms for China and it was under special control of the USSR government. The building of plant was bound by great difficulties conditioned by range of project, specifics of production conditions in China, special requests of customer, necessity to manufacture non-standard equipment. The implementation of this project of enormous humanitarian significance was at the same time manifestation of concurrence between the USSR and the USA for geopolitical and ideological influence in East Asia.

Covalent penicillin-protein conjugates elicit anti-drug antibodies that are clonally and functionally restricted.

Many archetypal and emerging classes of small-molecule therapeutics form covalent protein adducts. In vivo, both the resulting conjugates and their off-target side-conjugates have the potential to elicit antibodies, with implications for allergy and drug sequestration. Although ß-lactam antibiotics are a drug class long associated with these immunological phenomena, the molecular underpinnings of off-target drug-protein conjugation and consequent drug-specific immune responses remain incomplete. Here, using the classical ß-lactam penicillin G (PenG), we probe the B and T cell determinants of drug-specific IgG responses to such conjugates in mice. Deep B cell clonotyping reveals a dominant murine clonal antibody class encompassing phylogenetically-related IGHV1, IGHV5 and IGHV10 subgroup gene segments. Protein NMR and x-ray structural analyses reveal that these drive structurally convergent binding modes in adduct-specific antibody clones. Their common primary recognition mechanisms of the penicillin side-chain moiety (phenylacetamide in PenG)-regardless of CDRH3 length-limits cross-reactivity against other ß-lactam antibiotics. This immunogenetics-guided discovery of the limited binding solutions available to antibodies against side products of an archetypal covalent inhibitor now suggests future potential strategies for the 'germline-guided reverse engineering' of such drugs away from unwanted immune responses.

Risk of Self-Reported Penicillin Allergy Despite Removal of Penicillin Allergy Label: Secondary Analysis of the PALACE Randomized Clinical Trial.

This secondary analysis of adult patients in the Penicillin Allergy Clinical Decision Rule (PALACE) Study investigates the risk of self-reported penicillin allergy despite removal of penicillin allergy label.

Leveraging implementation science theories to develop and expand the use of a penicillin allergy de-labeling intervention.

BACKGROUND: Penicillin allergy is the most frequently reported drug allergy, yet most patients can tolerate the drug if challenged. Despite this discrepancy, large scale penicillin allergy de-labeling interventions have not been widely implemented in many health care systems. The application of a multi-method implementation science approach can provide key tools to study this evidence to practice gap and provide insight to successfully operationalize penicillin allergy evaluation in real-world clinical settings. METHODS: We followed a four-step process that leverages qualitative analysis to design evidence-based, actionable strategies to develop an intervention. First, we specified the clinician-perceived barriers to penicillin allergy de-labeling (intervention targets). We then mapped intervention targets onto Theoretical Domains Framework (domains and constructs) and found the root causes of behavior. Next, we linked root causes of behavior with intervention functions (BCW). In the final step, we synthesized participants' suggestions for process improvement with implementation strategies aligning with the intervention functions. RESULTS: Evidence-based strategies such as focused education and training in penicillin allergy evaluation can address knowledge and confidence barriers reported by frontline clinicians. Other key strategies involve developing a system of champions, improving communications systems, and restructuring the healthcare team. Implementation mapping can provide a powerful multi-method framework to study, design, and customize intervention strategies. CONCLUSION: Empowering clinicians beyond allergy specialists to conduct penicillin allergy assessments requires designing new workflows and systems and providing additional knowledge to those clinicians.

Primary somatosensory cortex CB1 and 5­HT1A receptors interaction in the penicillin model of epilepsy.

Cannabinoid and serotonin systems regulate many biological processes. The aim of the present study was to investigate the functional interaction between the cannabinoid and serotonergic systems of the primary somatosensory region (S1) of the brain in epileptiform activity caused by penicillin. The ACEA (an agonist of CB1 receptor), AM­251 (an antagonist of CB1 receptor), 8­OH­DPAT (an agonist of 5­HT1A receptor) and WAY­100635 (an antagonist of 5­HT1A receptor) were administered into the S1 after the same site administration of penicillin in urethane­anesthetized rats. Electrocorticographic recording was done for a 90­min period. The spike waves number and amplitude were recorded in 15­min intervals. Areas under the curve (AUC) of the above­mentioned spike alterations was calculated in 90 min. Spike waves with frequency of 30/min and amplitude of 1.3 mV were appeared after penicillin microinjection. The ACEA (50 ng), 8­OH­DPAT (500 ng) and ACEA (10 ng) plus 8­OH­DPAT (100 ng) reduced epileptiform activity. The AM­251 (50 ng) and WAY­100365 (500 ng) prevented the reducing effects of ACEA (50 ng) and 8­OH­DPAT (500 ng). The AM­251 alone increased spike waves frequency. The AUC results supported the effects of the above­mentioned treatments. The results showed that activating CB1 and 5­HT1A receptors in the S1 may reduce the epileptiform activity caused by penicillin. Therefore, alone and together activation of central CB1 and 5­HT1A receptors might be considered in the management of epilepsy treatment.

Penicillin concentrations in oropharyngeal and frontal sinus tissue following enteral and intravenous administration measured by microdialysis in a porcine model.

BACKGROUND: Penicillin may be administered enterally or intravenously for the treatment of bacterial infections within the oropharynx and the frontal sinuses. We aimed to assess and compare penicillin concentrations in oropharyngeal and frontal sinus tissues following enteral and intravenous administration in a porcine model. METHOD: Twelve pigs were randomized to receive either enteral (0.8 g Penicillin V) or intravenous (1.2 g Penicillin G) penicillin. Microdialysis was used for sampling in oropharyngeal and frontal sinus tissues during a six-hour dosing interval. In addition, plasma samples were collected. The primary endpoints were time with drug concentration above the minimal inhibitory concentration (T>MIC) for two MIC targets: 0.125 (low target) and 0.5 (high target) µg/mL (covering Group A Streptococci, Fusobactarium necrophorum, Streptococcus pneumoniae and Hemophilus influenza) and attainment of these treatment targets for ≥50 % T>MIC. RESULTS: For both the low and high MIC targets, intravenous administration resulted in higher T>MIC in oropharyngeal and frontal sinus tissues compared to enteral administration. In oropharyngeal tissue, the treatment target (≥50 % T>MIC) was achieved for both the low target (96 %) and high target (68 %) when penicillin was administrated intravenously. In frontal sinus tissue, the treatment target was reached for the low target (70 %), but not the high target (35 %) when administered intravenously. None of the two tissues reached the treatment targets when penicillin was administered enterally. CONCLUSION: Intravenous administrated penicillin in standard dosage is superior to enteral administration of penicillin in standard dosage in achieving clinically important T>MIC as the majority of targets were achieved following intravenously administration, while none of the targets were achieved following enteral administration. These results support the general notion of higher tissue concentrations following intravenous compared to enteral administration.

Geographical migration and fitness dynamics of Streptococcus pneumoniae.

Streptococcus pneumoniae is a leading cause of pneumonia and meningitis worldwide. Many different serotypes co-circulate endemically in any one location1,2. The extent and mechanisms of spread and vaccine-driven changes in fitness and antimicrobial resistance remain largely unquantified. Here using geolocated genome sequences from South Africa (n = 6,910, collected from 2000 to 2014), we developed models to reconstruct spread, pairing detailed human mobility data and genomic data. Separately, we estimated the population-level changes in fitness of strains that are included (vaccine type (VT)) and not included (non-vaccine type (NVT)) in pneumococcal conjugate vaccines, first implemented in South Africa in 2009. Differences in strain fitness between those that are and are not resistant to penicillin were also evaluated. We found that pneumococci only become homogenously mixed across South Africa after 50 years of transmission, with the slow spread driven by the focal nature of human mobility. Furthermore, in the years following vaccine implementation, the relative fitness of NVT compared with VT strains increased (relative risk of 1.68; 95% confidence interval of 1.59-1.77), with an increasing proportion of these NVT strains becoming resistant to penicillin. Our findings point to highly entrenched, slow transmission and indicate that initial vaccine-linked decreases in antimicrobial resistance may be transient.

First-line treatment with ceftriaxone for Neisseria gonorrhoeae infection less likely to be prescribed to patients with a penicillin allergy label: a retrospective audit of medical records.

Background Gonorrhoea notifications have increased substantially in Australia over the past decade. Neisseria gonorrhoeae is already highly resistant to several antibiotics and so, alternatives to first-line treatment are generally strongly discouraged. The penicillin allergy label (AL) on patient medical records has previously been shown to influence prescribing practices, to the detriment of best-practice management and antimicrobial stewardship. This study aimed to understand how the penicillin AL influences antibiotic selection for gonorrhoea treatment at Canberra Sexual Health Centre. Methods A retrospective chart audit of gonorrhoea cases treated at Canberra Sexual Health Centre between January 2020 and October 2023 (n =619 patients, n =728 cases). Antibiotic selection was assessed according to penicillin AL status. Ceftriaxone selection was assessed according to penicillin allergy severity reported in the medical records and as determined using a validated antibiotic allergy assessment tool. Results Cases with a penicillin AL were more likely to receive antibiotics other than ceftriaxone (n =7/41, 17.1%) than cases without the label (n =8/687, 1.2%, P n =28/41, 68.3%) to apply the assessment tool. Those reported as low-severity in the records were more likely to receive ceftriaxone (n =21/22, 95.5%) than those reported as moderate-high (n =7/11, 63.6%) or unreported (n =6/8, 0.75%). Conclusions Treatment of gonorrhoea in outpatient settings requires an understanding of penicillin allergy, and the ability to quickly and accurately identify penicillin-AL patients who can safely tolerate ceftriaxone. Institutionally endorsed penicillin allergy de-labelling protocols and access to easy-to-navigate prescribing advice within national sexually transmitted infection management guidelines would support this.