Flowchart for predicting achieving the target area under the concentration-time curve of vancomycin in critically ill Japanese patients: A multicenter retrospective study

INTRODUCTION

In therapeutic drug monitoring (TDM) of vancomycin (VCM), the area under the concentration-time curve (AUC) is related to the clinical efficacy and toxicity. Therefore, herein, we examined the factors associated with achieving the target AUC at follow-up and developed a decision flowchart for achieving the target AUC in critically ill patients.

METHODS

This multicenter retrospective observational study was conducted at eight hospitals. We retrospectively analyzed data from patients who had received VCM in the intensive care unit from January 2020 to December 2022. Decision-tree (DT) analysis was performed using factors with p < 0.1 in univariate analysis as the independent variables. Case data were split up to two times, and four subgroups were included. The primary endpoint was achieving the target AUC at the follow-up TDM (AUCfollow-up) and target AUCfollow-up achievement was defined as an AUC of 400-600 μg‧h/mL. The initial AUC values were calculated with the 2-point concentrations (peak and trough) using the Bayesian estimation software Practical AUC-guided TDM (PAT).

RESULTS

Among 70 patients (median age [interquartile range], 66 [56, 79] years; 50 % women), the AUCfollow-up was achieved in 70 % (49/70). Three factors were selected for the decision flow chart: predicted AUCfollow-up of 400-600 μg‧h/mL, dosing at 12-h intervals, and CCr of 130 mL/min/1.73 m2 or higher; the accuracy was adequate (92 %, R2 0.52).

CONCLUSION

We successfully identified the factors associated with achieving the target AUC of VCM at follow-up TDM and developed a simple-to-use DT model. However, the validity of the findings needs to be evaluated.

Model-informed precision dosing of vancomycin for rapid achievement of target area under the concentration-time curve: A simulation study

In this study, we aimed to evaluate limited sampling strategies for achieving the therapeutic ranges of the area under the concentration-time curve (AUC) of vancomycin on the first and second day (AUC0-24 , AUC24-48 , respectively) of therapy. A virtual population of 1000 individuals was created using a population pharmacokinetic (PopPK) model, which was validated and incorporated into our model-informed precision dosing tool. The results were evaluated using six additional PopPK models selected based on a study design of prospective or retrospective data collection with sufficient concentrations. Bayesian forecasting was performed to evaluate the probability of achieving the therapeutic range of AUC, defined as a ratio of estimated/reference AUC within 0.8-1.2. The Bayesian posterior probability of achieving the AUC24-48 range increased from 51.3% (a priori probability) to 77.5% after using two-point sampling at the trough and peak on the first day. Sampling on the first day also yielded a higher Bayesian posterior probability (86.1%) of achieving the AUC0-24 range compared to the a priori probability of 60.1%. The Bayesian posterior probability of achieving the AUC at steady-state (AUCSS ) range by sampling on the first or second day decreased with decreased kidney function. We demonstrated that second-day trough and peak sampling provided accurate AUC24-48 , and first-day sampling may assist in rapidly achieving therapeutic AUC24-48 , although the AUCSS should be re-estimated in patients with reduced kidney function owing to its unreliable predictive performance.

Comparison of the efficacy and safety of standard- and high-dose daptomycin: A systematic review and meta-analysis

AIMS

Standard doses of daptomycin at 4 and 6 mg/kg were used for the treatment of skin and soft tissue for infections and bacteraemia, respectively. However, increased doses of daptomycin are recommended for complicated infections by Gram-positive organisms.

METHODS

A systematic review was conducted using 4 databases. We compared treatment success between standard-dose (SD, 4-6 mg/kg) and high-dose (HD, >6 mg/kg) daptomycin in patients with all-cause bacteraemia, complicated bacteraemia, infective endocarditis, osteomyelitis and foreign body/prosthetic infection as the primary outcome. We also compared the success between SD and HD2 (≥8 mg/kg) daptomycin treatments in patients with these diseases as the secondary outcome. The incidence of creatine phosphokinase (CPK) elevation was evaluated as safety.

RESULTS

In patients with complicated bacteraemia and infective endocarditis, the treatment success was significantly lower in the SD group than in the HD group (odds ratio [OR] 0.48, 95% confidence interval [CI] 0.30-0.76 and OR 0.50, 95% CI 0.30-0.82) and HD2 group (OR 0.38, 95% CI 0.21-0.69 and OR 0.30, 95% CI 0.15-0.60), respectively. A significant difference was demonstrated only in the HD2 group in patients with bacteraemia, including simple infection. SD did not decrease the success rate for the treatment of osteomyelitis and foreign body/prosthetic infection. The incidence of elevated CPK was significantly lower in SD group than in HD group.

CONCLUSION

SD daptomycin was associated with significantly lower treatment success than HD in patients with complicated bacteraemia/infective endocarditis. The CPK elevation should be considered in patients treated with high daptomycin doses.

Optimal therapeutic recommendation for Clostridioides difficile infection in pediatric and adolescent populations: a systematic review and meta-analysis

We conducted a systematic review and meta-analysis to examine the efficacy profiles of metronidazole (MNZ) and vancomycin (VCM) in pediatric and adolescent patients with Clostridioides difficile infection (CDI). A systematic review and meta-analysis was conducted using four electronic databases (PubMed, Cochrane Library, Web of Science, and Clinicaltrials.gov) through July 6, 2022. We analyzed the clinical cure and recurrence rates to determine the efficacy of MNZ and VCM. The clinical cure rates in all included studies were not significantly different between MNZ and VCM (OR = 0.63; 95% CI = 0.36-1.10; I² = 0%; P = 0.10). Subgroup analyses were performed separately for each region to account for regional differences in the CDI. MNZ treatment achieved significantly lower clinical cure rates than did VCM in the United States of America (USA) and Europe (OR = 0.42, 95% CI = 0.19-0.93, I² = 0%, P = 0.03). Recurrence rates were not significantly different between MNZ and VCM (OR = 1.48, 95% CI = 0.62-3.53, I² = 28%, P = 0.38).    Conclusion: MNZ exhibited significantly lower clinical cure rates than did VCM in the US and Europe; therefore, it is not recommended for the management of CDI in pediatric and adolescent populations. What is Known: • The unavailability of robust data on recommendations of therapeutic agents for the management of Clostridioides difficile infections in children precludes effective antibiotic choice. What is New: • Metronidazole exhibited significantly lower clinical cure rates than did vancomycin in the United States of America and Europe and recurrence rate was not significantly different between metronidazole and vancomycin; therefore, it is not recommended for the management of Clostridioides difficile infection in children.

Model-informed precision dosing of teicoplanin for the rapid achievement of the target area under the concentration-time curve: A simulation study

Teicoplanin, a glycopeptide antimicrobial, is recommended for therapeutic drug monitoring, but it remains unclear how to target the area under the concentration-time curve (AUC). This simulation study purposed to demonstrate the potential of the Bayesian forecasting approach for the rapid achievement of the target AUC for teicoplanin. We generated concordant and discordant virtual populations against a Japanese population pharmacokinetic model. The predictive performance of the Bayesian posterior AUC in limited sampling on the first day against the reference AUC was evaluated as an acceptable target AUC ratio within the range of 0.8-1.2. In the concordant population, the probability for the maximum a priori or Bayesian posterior AUC on the first day (AUC_0-24 ) was 61.3% or more than 77.0%, respectively. The Bayesian posterior AUC on the second day (AUC_24-48 ) was more than 75.1%. In the discordant population, the probability for the maximum a priori or Bayesian posterior AUC_0-24 was 15.5% or 11.7-80.7%, respectively. The probability for the maximum a priori or Bayesian posterior AUC_24-48 was 23.4%, 30.2-82.1%. The AUC at steady-state (AUC_SS ) was correlated with trough concentration at steady-state, with a coefficient of determination of 0.930; the coefficients on days 7 and 4 were 0.442 and 0.125, respectively. In conclusion, this study demonstrated that early sampling could improve the probability of AUC_0-24 and AUC_24-48 but did not adequately predict AUC_SS . Further studies are necessary to apply early sampling-based model-informed precision dosing in the clinical settings.

Target Therapeutic Ranges of Anti-MRSA Drugs, Linezolid, Tedizolid and Daptomycin, and the Necessity of TDM

The target therapeutic ranges of vancomycin, teicoplanin, and arbekacin have been determined, and therapeutic drug monitoring (TDM) is performed in clinical practice. However, TDM is not obligatory for daptomycin, linezolid, or tedizolid. In this study, we examined whether TDM will be necessary for these 3 drugs in the future. There was no significant difference in therapeutic effects on acute bacterial skin and skin structure infection between linezolid and tedizolid by meta-analysis. Concerning the therapeutic effects on pneumonia, the rate of effectiveness after treatment with tedizolid was significantly lower than with linezolid. With respect to safety, the incidences of gastrointestinal adverse events and blood/lymphatic system disorders related to tedizolid were significantly lower than those related to linezolid. Linezolid exhibits potent therapeutic effects on pneumonia, but the appearance of adverse reactions is indicated as a problem. There was a dose-dependent decrease in the platelet count, and the target trough concentration (C_trough) was estimated to be 4-6 or 2-7 µg/mL in accordance with the patient's condition. The efficacy of linezolid may be obtained while minimizing the appearance of adverse reactions by performing TDM. The target therapeutic range of tedizolid cannot be achieved in immunocompromised or severe patients. Therefore, we concluded that TDM was unnecessary, considering step-down therapy with oral drugs, use in non-severe patients, and high-level safety. Concerning daptomycin, high-dose administration is necessary to achieve an area under the curve (AUC) of ≥666 as an index of efficacy. To secure its safety, C_trough (<20 µg/mL) monitoring is important. Therefore, TDM is necessary.

[Suppurative Thrombophlebitis of the Posterior Neck Caused by Streptococcus constellatus: A Case Report and Literature Review]

We report a rare case of suppurative thrombophlebitis of the posterior neck caused by Streptococcus constellatus. A 69-year-old female patient was admitted to the hospital with neck pain and fever, which had persisted for 16 days prior to hospitalization. On day 1 (day of admission), blood cultures (later identifying S. constellatus) were performed, and ceftriaxone (CTRX) IV (2 g SID) was started. On day 3, suppurative thrombophlebitis of the posterior neck was diagnosed by CT scan. The antimicrobials were changed from CTRX to ampicillin/sulbactam IV (12 g QID) to guard against the possibility of complicated infection with Fusobacterium spp. or Prevotella spp. On day 17, a CT scan revealed that the thrombus remained. Therefore, oral edoxaban (30 mg SID) was started. On day 27, the patient was discharged after her medication was changed to oral amoxicillin/clavulanate (1500 mg/375 mg TID). On day 33, the amoxicillin/clavulanate was changed to oral cefaclor (1500 mg TID) and edoxaban was discontinued due to itching. On day 45, the course of cefaclor was completed. The patient went on to follow an uneventful course with no relapses or complications for two years since the conclusion of treatment. These results suggest that when a patient presents with persistent neck pain accompanied by fever, suppurative thrombophlebitis of the posterior neck should be considered. In antimicrobial therapy, the treatment could be switched from intravenous to oral. In addition, direct-acting oral anticoagulants may be an alternative to other forms of anticoagulants.

Incidence of elevated creatine phosphokinase between daptomycin alone and concomitant daptomycin and statins: a systematic review and meta-analysis

AIM

The present systematic review and meta-analysis evaluated the incidence of elevated creatine phosphokinase (CPK) levels between daptomycin alone and concomitant daptomycin and statin use.

METHODS

We searched the PubMed, Web of Sciences, Cochrane Library, and ClinicalTrials.gov databases. We analysed the incidence of elevated CPK between daptomycin alone and concomitant daptomycin and statins among studies defining CPK elevation as levels ≥ the upper limit of normal (ULN) or ≥ 5 times ULN. We also analysed the incidence of rhabdomyolysis between the groups. We then calculated the odds ratios (ORs) and 95% confidence intervals (CIs) based on the included studies.

RESULTS

Comparing CPK elevation defined as CPK levels ≥ ULN, a significantly higher incidence of CPK elevation was observed with concomitant daptomycin and statin use than with daptomycin alone (OR=2.55, 95% CI 1.78-3.64, p<0.00001, I² =0%). Likewise, when CPK elevation was defined as CPK levels ≥ 5 times ULN, a significantly higher incidence of CPK elevation was detected with concomitant daptomycin and statin use than with daptomycin alone (OR = 1.89, 95% CI 1.06-3.35, p=0.03, I² =48%). The incidence of rhabdomyolysis was significantly higher following concomitant daptomycin and statin use than with daptomycin alone (OR = 11.60, 95% CI 1.81-74.37, p=0.01, I² =0%).

CONCLUSIONS

The combined use of daptomycin and statins were significant risk factors for the incidence of CPK elevation defined as levels ≥ ULN or ≥ 5 times ULN and rhabdomyolysis.

Identification of Risk Factors for Daptomycin-Associated Creatine Phosphokinase Elevation and Development of a Risk Prediction Model for Incidence Probability

BACKGROUND

In this study, we investigated the risk factors for daptomycin-associated creatine phosphokinase (CPK) elevation and established a risk score for CPK elevation.

METHODS

Patients who received daptomycin at our hospital were classified into the non-elevated or elevated CPK group based on their peak CPK levels during daptomycin therapy. Univariable and multivariable analyses were performed, and a risk score and prediction model for the incidence probability of CPK elevation were calculated based on logistic regression analysis.

RESULTS

The non-elevated and elevated CPK groups included 181 and 17 patients, respectively. Logistic regression analysis revealed that concomitant statin use (odds ratio [OR], 4.45 [95% confidence interval {CI}, 1.40-14.47]; risk score 4), concomitant antihistamine use (OR, 5.66 [95% CI, 1.58-20.75]; risk score 4), and trough concentration (Cmin) between 20 and <30 µg/mL (OR, 14.48 [95% CI, 2.90-87.13]; risk score 5) and ≥30.0 µg/mL (OR, 24.64 [95% CI, 3.21-204.53]; risk score 5) were risk factors for daptomycin-associated CPK elevation. The predicted incidence probabilities of CPK elevation were <10% (low risk), 10%-<25% (moderate risk), and ≥25% (high risk) with total risk scores of ≤4, 5-6, and ≥8, respectively. The risk prediction model exhibited a good fit (area under the receiver operating characteristic curve, 0.85 [95% CI, .74-.95]).

CONCLUSIONS

These results suggested that concomitant use of statins with antihistamines and Cmin ≥20 µg/mL were risk factors for daptomycin-associated CPK elevation. Our prediction model might aid in reducing the incidence of daptomycin-associated CPK elevation.

Support for fungal infection treatment mediated by pharmacist-led antifungal stewardship activities

OBJECTIVE

At the Yokohama General Hospital, pharmacist-led antimicrobial stewardship programs (ASP) including antifungal stewardship programs (AFP) were started in 2012. To investigate the efficacy of the programs, we compared several parameters that are recommended for the measurement of ASP in Japan based on pre- and post-AFP activities.

PATIENTS AND METHODS

The subjects were inpatients who developed candidemia between April 2008 and March 2016. They were divided into two groups: pre-AFP (April 2008 until March 2012) and post-AFP (April 2012 until March 2016). The results were compared between the two groups.

RESULTS

The cumulative optimal antifungal drug usage rate, as a process parameter, significantly increased in the post-AFP group (p = 0.025). Furthermore, the days of therapy of antifungal drugs in the pre- and post-AFP groups was median 6.0 (interquartile range [IQR] 0.3-15.7) and median 3.4 (IQR 1.9-3.4) per 1,000 patient-days, respectively; there was a significant decrease in the post-AFP group (p < 0.001). Expenditure on antifungal drugs, as an outcome parameter, in the pre- and post-AFP groups was 9390.5 ± 5687.1 and 5930.8 ± 4687.0 US dollars, respectively; there was a significant decrease in the post-AFP group (p = 0.002).

CONCLUSIONS

These results suggest that pharmacist-led antifungal stewardship activities improve both outcome and process parameters.

Peculiar clinical features of cellulitis in peripheral lymphedema

Although the occurrence of cellulitis in lymphedema (LE) is believed to be an infection-related event, many findings in its clinical course seem to suggest that it is unlikely to be an infection. Therefore, we tried to clarify the specific features of cellulitis in LE. In-hospital courses of cellulitis obtained from medical charts were reviewed in the patients with leg LE (LE; 24 patients, 72admissions), chronic venous insufficiency (CVI; 28 patients, 29 admissions), and leg cellulitis secondary to wound infection without underlying disease (N; 42 patients, 42 admissions). The patients with LE complained of less local pain (peak numerical scale; LE: 1.4 ± 1.7, CVI: 4.1 ± 2.5, N: 3.2 ±2.0, p < 0.0001), showed an abnormally higher peak procalcitonin level (LE: 33.8 ± 34.8 (N = 7), CVI: 2.9 ± 5.8 (N = 8), N: 0.4 ± 0.6(N = 10), p < 0.05), and required fewer antibiotics (LE: 1.1 ± 0.3, CVI: 1.8 ± 0.9, N: 1.5 ± 0.9, p < 0.0001). These findings suggested that the occurrence of cellulitis in LE seems unlikely to be an infection-related type of cellulitis similar to that found in CVI.

Effect of three-size too large strong stocking on venous hemodynamics in normal subjects

OBJECTIVES

To study the differences in impact on venous hemodynamics between larger size strong graduated elastic compression stockings (GECS) and appropriate size strong/moderate GECS.

METHOD

In healthy legs fitted for a small (Group S; n = 8) and large (Group L; n = 8) GECS, air plethysmography was performed without GECS, with an appropriate size strong GECS (GECS1), with a three-size too large strong GECS (GECS2), and with an appropriate size moderate GECS (GECS3) in this order.

RESULTS

In Group S, interface pressure with GECS2 was equal to or higher than that with GECS3. Decreased venous volume, unchanged ejection volume, and decreased residual volume were achieved by GECS, but differences in these parameters among GECS were not observed. Although insignificant, a similar tendency was found in Group L.

CONCLUSIONS

A larger size strong GECS seemed to have equivalent interface pressure and impact on venous hemodynamics compared to an appropriate size moderate or strong GECS.

Study on different bandages and application techniques for achieving stiffer compression

OBJECTIVES

The objective of this study was to investigate the relationship between interface pressure and stiffness of compression achieved by various combinations of bandages and application techniques.

METHOD

There were eight healthy volunteers. One roll (4.5 m) of four types of bandages with different extensibilities (0, 90, 108 and 218%) was applied to the leg in single-layer bandage fashion with eight random tensions. Then, the leg was wrapped with one to eight rolls in multi-layer bandage fashion.

RESULTS

Each combination of bandage and application technique displayed an indigenous linear interface pressure-static stiffness index relationship. With single-layer bandage, lower extensibility was associated with higher static stiffness index at a given interface pressure. With multi-layer bandage, the static stiffness index at a given interface pressure was independent of the bandage type.

CONCLUSION

The stiffness at a given interface pressure was affected by the extensibility with single-layer bandage but not with multi-layer bandage.

Sex effects on rate of change of P300 latency with age

OBJECTIVE

Recent MRI evidence suggests that neuroanatomic structures may change more rapidly with age in males compared with females. Sex differences for P300 latency were tested to determine whether similar results might appear for P300 latency, a neurophysiological measure sensitive to age and neurodegenerative processes.

METHODS

Auditory event related potentials (ERPs) were recorded using an auditory 'oddball' to elicit the N200 and P300 components. Forty-two male and 42 female healthy normal subjects (age range 15-85 years) were entered in this study. Both linear and curvilinear correlations of N200 and P300 latency/amplitude with age were tested.

RESULTS

The slope of P300 latency on age for males was steeper than for females at Pz in subjects who were 30 years of age and older. N200 and P300 latencies were inversely correlated with age in young adult males (<30 years old).

CONCLUSIONS

Males may experience more rapid change of P300 latency, but not amplitude, than females in middle to old age. Further research is required to determine whether those change reflects neural pathophysiology, or is mediated by such factors as neuroanatomic differences, body temperature, or mild auditory deficits.

Synthetic lipid A-induced uveitis and endotoxin-induced uveitis--a comparative study

Endotoxin-induced uveitis (EIU) is an animal model of ocular inflammation induced by lipopolysaccharide (LPS). The lipid A (LA) region of the LPS chemical structure is believed to be responsible for virtually all the biological activities induced by LPS. The aim of this study was to perform a more detailed investigation of the potency of LA in reproducing EIU. Various doses of either LPS or LA were injected into the footpad of an inbred strain of Lewis rat and the inflammation patterns were compared by assessing the protein concentration, by cytological study, and by determining the inflammatory cell content in samples of aqueous humor obtained during 96-hour follow-up. Evaluation of the cell number and protein concentration ratio of both groups showed the LA-stimulated group presented a higher ratio than the LPS group (Welch's t-test, (P < 0.00001). It was noteworthy that even the injection of high doses of LPS could not reproduce the level of cellular infiltration induced by LA. Histological study confirmed the enhanced cellularity in the LA group, neutrophils being predominant in both the LPS- and the LA-stimulated groups. The divergent findings in these two models of uveitis may be valuable to further investigations of the process of inflammatory cell migration into the anterior chamber of the eye.

[Intraosseous meningioma associated with lung cancer: a case of multiple neoplasms]

Intraosseous tumor was found in a 63 year old male patient with lung cancer during metastatic work-up study. Plain skull X-ray film showed a large osteolytic lesion in the left temporo-parietal bone. Bone and Ga scintigrams revealed an increased activity in this lesion. CT scan demonstrated an isodense lentiform configuration, which was homogeneously enhanced with contrast medium. It was iso-intense in T1, and high-intense in T2 and proton weighted MR images. The tumor was removed en bloc with surrounding normal bone. The attached dura was markedly thickened, but there was no tumor infiltration. Histological diagnosis was transitional meningioma with psammoma body. Postoperatively he was transferred back to Okinawa Hospital and right lower lobectomy was performed for the lung tumor. Histological diagnosis was well-differentiated adenocarcinoma. We examined immunohistochemically p53 protein expression, but p53 immunoactivity was observed in neither tumor. Multiple neoplasms associated with brain tumor are relatively rare, but the incidence will increase in the future as the diagnostic work-up develops. Pathological diagnosis will give us the decisive opportunity for proper treatment. It is to be stressed that, in multiple neoplasms, care should be taken to avoid misdiagnosis of metastasis.