Estimated glomerular filtration rate as a tool for early identification of patients with insufficient exposure to beta-lactam antibiotics in intensive care units

BACKGROUND

Only about 50% of intensive care unit (ICU) patients reach a free trough concentration above MIC (100% fT > MIC) of beta-lactam antibiotics. Although dose adjustments based on therapeutic drug monitoring (TDM) could be beneficial, TDM is not widely available. We investigated serum creatinine-based estimated GFR (eGFR) as a rapid screening tool to identify ICU patients at risk of insufficient exposure.

METHOD

Ninety-three adult patients admitted to four ICUs in southeast Sweden treated with piperacillin/tazobactam, meropenem, or cefotaxime were included. Beta-lactam trough concentrations were measured. The concentration target was set to 100% fT > MICECOFF (2, 4, and 16 mg/L based on calculated free levels for meropenem, cefotaxime, and piperacillin, respectively). eGFR was primarily determined via Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) and compared to three other eGFR equations. Data was analysed using logistic regression and receiver operative characteristic (ROC) curves.

RESULTS

With intermittent standard dosing, insufficient exposure was common in patients with a relative eGFR ≥48mL/min/1.73m2 [85%, (45/53)], particularly when treated with cefotaxime [96%, (24/25)]. This eGFR cut-off had a sensitivity of 92% and specificity of 82% (AUC 0.871, p < 0.001) in identifying insufficient exposure. In contrast, patients with eGFR <48mL/min/1.73m2 had high target attainment [90%, (36/40)] with a wide variability in drug exposure. There was no difference between the four eGFR equations (AUC 0.866-0.872, cut-offs 44-51 ml/min/1.73m2).

CONCLUSION

Serum creatinine-based eGFR is a simple and widely available surrogate marker with potential for early identification of ICU patients at risk of insufficient exposure to piperacillin, meropenem, and cefotaxime.

Introduction of a penicillin allergy de-labelling program with direct oral challenge and its effects on utilization of beta-lactam antimicrobials: a multicenter retrospective parallel cohort study

BACKGROUND

Self-reported penicillin allergy labels are common and often inaccurate after assessment. These labels can lead to reduced use of first-line beta-lactam antibiotics and worse outcomes. We measured the impact of a previously performed inpatient proactive systematic penicillin allergy de-labelling program on subsequent antibiotic use. This prior program included assessment, risk-stratification, and low risk direct oral amoxicillin challenge.

METHODS

We performed a retrospective comparison of parallel cohorts from two separate tertiary care hospital campuses in Ottawa, Canada across two penicillin de-labelling intervention periods across April 15th to April 30th, 2021, and February 15th to March 8th, 2022. Outcomes, including penicillin allergy labelling and antibiotic use, were collected for the index admission and the subsequent 6-month period. Descriptive statistics and multivariate regression analyses were performed.

RESULTS

A total of 368 patients with penicillin allergy label were included across two campuses and study periods. 24 (13.8%) patients in the intervention groups had sustained penicillin allergy label removal at 30 days from admission vs. 3 (1.5%) in the non-intervention group (p < 0.001). In the 6-months following admission, beta-lactams were prescribed more frequently in the intervention groups vs. the non-intervention groups for all patients (28 [16.1%] vs.15 [7.7%], p = 0.04) and were prescribed more frequently amongst those who received at least one antibiotic (28/46 [60.9%] vs.15/40 [37.5%], p = 0.097). In a multivariate regression analysis, the intervention groups were found to be associated with an increased odds of beta-lactam prescribing in all patients (OR 2.49, 95%CI 1.29-5.02) and in those prescribed at least one antibiotic (OR 2.44, 95%CI 1.00-6.15). No drug-related adverse events were reported.

CONCLUSIONS

Proactive penicillin allergy de-labelling for inpatients was associated with a reduction in penicillin allergy labels and increased utilization of beta-lactams in the subsequent 6-months.

Assessment of antibacterial drug utilization patterns and antibiogram in infectious diseases: a prospective cross-sectional study

BACKGROUND

Antibacterial drugs are successful in combating most types of infections. Irrational use and higher consumption of these drugs can give rise to the antibiotic resistance globally.

OBJECTIVE

To evaluate antibacterial drug prescribing patterns and antibiogram in infectious disease cases admitted to the hospital.

METHODS

A cross-sectional, observational study was conducted from September 2019 to February 2020 among inpatients ward at the hospital after ethical approval. All the data was analysed by the mean and percentage values using Microsoft excel.

RESULTS

Out of 250 admitted patients, males and females were 156 (62%) and 94 (38%) respectively. The majority of patients 79 (32%) belonged to the age group of 20-40 years. The majority of prescriptions reported were for viral fever 48 (19%), lower respiratory tract infections 40 (16%) and dengue 33 (13%). Antibacterial drugs administered through the intravenous route and the oral route were 301 (83%) and 63 (17%) respectively. The most frequently utilized antibacterial drugs were beta-lactam class ceftriaxone 149 (60%) and the fixed-dose combination, amoxicillin plus clavulanic acid 65 (26%). Further highly prescribed antibacterial drugs were metronidazole 52 (21%), azithromycin 36 (15%), and levofloxacin 24 (10%). In Gram-negative bacteria, Escherichia coli 6 (30%) contributed majorly, while in Gram-positive coagulase-negative, Staphylococci 6 (30%) contributed the highest growth of bacteria for the specific infections in the admitted cases.

CONCLUSION

Ceftriaxone and the amoxicillin-clavulanic acid combination were highly prescribed among all antibacterial drugs, followed by metronidazole and azithromycin. The current study showed that in the antibiogram pattern, Escherichia coli and coagulase-negative Staphylococci contributed significantly as causative organisms for infectious disease cases. The present study highlighted demographic distribution, infectious diseases with their antibacterial drug utilization patterns and antibiogram assessment in the admitted patients.

Relationship of Reaction History to Positive Penicillin Skin Tests

BACKGROUND

Previous data suggest that up to one-third of patients classified as allergic based on positive penicillin skin tests have a vague reaction history. Direct oral challenge (DOC) has been recommended for patients with a low-risk reaction history. A variety of published models stratify reaction risk to guide the use of DOC.

OBJECTIVE

To reassess the proportion of penicillin skin test-positive patients with vague or low-risk reaction histories and evaluate the relationship between the reaction risk history and the likelihood of positive skin test results.

METHODS

We identified patients who underwent penicillin allergy evaluation over a 5-year period. We recorded drug reaction history, demographic variables, skin testing, and challenge results. Matched controls whose skin tests were negative were identified for skin test-positive patients. Drug reaction histories were assigned a risk category based on 2 previously published risk stratification models. We used logistic regression to investigate whether reaction history risk was associated with positive skin test results.

RESULTS

Penicillin skin testing was performed in 3382 patients; 207 (6.1%) were positive. Positive skin tests were more frequent in outpatients (P < .001), younger patients (P < .001), and female patients (P < .001). Percentages of each risk category in each model were similar in cases versus matched controls. The likelihood for positive skin tests increased with a high-risk reaction history in one stratification model.

CONCLUSION

Our data confirm that a substantial proportion of patients who self-report penicillin allergy and have positive skin test results have a low-risk history and imply that penicillin skin testing is associated with a poor positive predictive value.

The clinical and paraclinical effectiveness of four-hour infusion vs. half-hour infusion of high-dose ampicillin-sulbactam in treatment of critically ill patients with sepsis or septic shock: An assessor-blinded randomized clinical trial

PURPOSE

This study was conducted to determine whether critically ill patients admitted to the intensive care unit (ICU) with sepsis and septic shock may benefit from extended infusion of ampicillin/sulbactam compared with those receiving intermittent infusion.

MATERIAL AND METHODS

This randomized assessor-blinded clinical trial was conducted in the ICUs of Nemazee and Shahid Rajaee hospital, Shiraz, Iran, from August 2019 to August 2021. The participants randomly received 9 g Ampicillin/Sulbactam every 8 h by either extended (infused over 4 h) or intermittent (infused over 30 min) intravenous infusion if their estimated glomerular filtration rate based on Cockrorft-Gault formula was higher than 60 ml/min.

RESULTS

Totally, 136 patients were enrolled and allocated to the intervention and control groups, each with 68 patients. Clinical cure was significantly higher in the extended group (P = 0.039), but ICU and hospital length of stay did not differ between the groups (P = 0.87 and 0.83, respectively). The ICU (P = 0.031) and hospital (P = 0.037) mortality rates in the extended infusion group were significantly lower than those in the intermittent infusion group.

CONCLUSION

These data should be replicated in larger clinical trials before providing any recommendation in favor of this method of administration in clinical practice.