Accuracy of Therapeutic Drug Monitoring of Teicoplanin at the Onset of Febrile Neutropenia.

Background and Objectives: Teicoplanin (TEIC) is an effective drug for patients with febrile neutropenia (FN); however, it has been reported that these patients may have increased TEIC clearance compared with patients who do not have FN. The purpose of this study was to study therapeutic drug monitoring in patients with FN when the TEIC dosing design was based on the population mean method. Materials and Methods: Thirty-nine FN patients with hematological malignancy were included in the study. To calculate the predicted blood concentration of TEIC, we used the two population pharmacokinetic (population PK) parameters (parameters 1 and 2) reported by Nakayama et al. and parameter 3, which is a modification of the population PK of Nakayama et al. We calculated the mean prediction error (ME), an indicator of prediction bias, and the mean absolute prediction error (MAE), an indicator of accuracy. Furthermore, the percentage of predicted TEIC blood concentration within 25% and 50% of the measured TEIC blood concentration was calculated. Results: The ME values were -0.54, -0.25, and -0.30 and the MAE values were 2.29, 2.19, and 2.22 for parameters 1, 2, and 3, respectively. For all of the three parameters, the ME values were calculated as minus values, and the predicted concentrations tended to be biased toward smaller values relative to the measured concentrations. Patients with serum creatinine (Scr) < 0.6 mg/dL and neutrophil counts < 100/µL had greater ME and MAE values and a smaller percentage of predicted TEIC blood concentration within 25% of measured TEIC blood concentrations compared with other patients. Conclusions: In patients with FN, the accuracy of predicting TEIC blood concentrations was good, with no significant differences between each parameter. However, patients with a Scr < 0.6 mg/dL and a neutrophil count < 100/µL showed slightly inferior prediction accuracy.

Sibling visits and viral infection in the neonatal intensive care unit.

BACKGROUND: Sibling visits to the neonatal intensive care unit (NICU) are a part of family-centered care, which is now being increasingly endorsed as a positive development in patient care. Sibling visits, however, pose a risk of viral infection, and hence many NICU in Japan impose strict limits on the practice. The aim of this study was therefore to assess whether sibling visits to the NICU are related to an increase in the nosocomial viral infection rate. METHODS: This retrospective study was conducted between April 2012 and March 2017 at Tokyo Metropolitan Children's Medical Center in Japan. Sibling visits were implemented after screening for symptoms of viral illness. Symptomatic patients in the NICU were tested for common viruses on rapid antigen test and polymerase chain reaction. The number of sibling visits and the rate of nosocomial viral infections were examined on Spearman's correlation test. RESULTS: The total number of sibling visits and rate of nosocomial viral infection in the NICU was 102 and 0.068 per 1,000 patient-days during the study period, respectively. The number of enterovirus, respiratory syncytial virus, human metapneumovirus, influenza virus A, and Herpes simplex virus infections was 3, 2, 1, 1, 1, and 1, respectively. No infections were identified after sibling visits. The number of sibling visits and the rate of nosocomial viral infections were not correlated (correlation coefficient, -0.1; P = 0.873). CONCLUSION: Sibling visits to the NICU did not result in an increase in the nosocomial viral infection rate.

Impact of computerized pre-authorization of broad spectrum antibiotics in Pseudomonas aeruginosa at a children's hospital in Japan.

BACKGROUND: The spread of antimicrobial-resistant organisms is a global concern. To stem this tide, an antimicrobial stewardship program at hospitals is essential to optimize the prescription of broad spectrum antibiotics. In this study we examined the impact of computerized pre-authorization for broad spectrum antibiotics for Pseudomonas aeruginosa at a children's hospital. METHODS: An antimicrobial stewardship program at Tokyo Metropolitan Children's Medical Center was assessed between March 2010 and March 2015. A paper-based post-prescription audit was switched to computerized pre-authorization for broad antipseudomonal agents in October 2011. The prescriber was required to obtain approval from physicians in the pediatric infectious diseases division before prescribing restricted antimicrobial agents. Approved prescriptions were processed and logged electronically. We evaluated days of therapy per 1000 patient-days, the cost of antibiotics, and the susceptibility of P. aeruginosa to piperacillin, ceftazidime, cefepime, piperacillin/tazobactam, carbapenems, and ciprofloxacin. Also, the average length of admission and infection-related mortality at 30 days were compared pre- and post-intervention. RESULTS: Administration of carbapenems, piperacillin/tazobactam, and ceftazidime decreased significantly after the introduction of computerized pre-authorization. Antibiotic costs were reduced by JPY2.86 million (USD 26,000) annually. None of the antipseudomonal agents showed decreased sensitivity. The average length of admission was shorter in post-intervention. Infection-related mortality at 30 days showed no difference between the pre- and post-intervention periods. CONCLUSION: An antimicrobial stewardship program using computerized pre-authorization decreased the use and cost of broad spectrum antibiotics without significant difference in infection-related mortality at 30 days, although our study did not improve susceptibilities of P. aeruginosa.

Ototoxicity and Nephrotoxicity With Elevated Serum Concentrations Following Vancomycin Overdose: A Retrospective Case Series.

Although a high vancomycin serum concentration is known to be associated with nephrotoxicity, its association with ototoxicity is not well known. The purpose of our study was to examine the latter association in pediatric patients, especially in cases of accidental overdose. Pediatric patients who received vancomycin at our facility between March 2010 and December 2015 with a serum trough concentration > 30 mg/L were enrolled. Age, sex, neonatal hearing screening results, estimated peak vancomycin serum concentration, duration of drug exposure, renal function, and hearing test results were collected. The estimated duration of concentrations above 30 or 80 mg/L were simulated with the Sawchuk-Zaske method. We defined a "high concentration" and "toxic concentration" of vancomycin as 30 to 80 mg/L and > 80 mg/L, respectively. Ototoxicity was assessed based on the auditory brain stem response. We identified 4 females and 2 males with normal hearing at birth. Four of the 6 patients were ≤ 3 months old. All the patients reached an estimated peak serum concentration of > 80 mg/L, and 5 exceeded 150 mg/L. The estimated duration of exposure to a high concentration and toxic concentration of vancomycin was 15 to 62 hours and 8 to 43 hours, respectively. All the patients experienced transient renal dysfunction. Although transient ototoxicity was found in 1 patient, prolonged ototoxicity was not observed in any of the patients. All the patients had received an accidental overdose of vancomycin. Prolonged hearing loss due to a high vancomycin serum concentration was not found in any of the subjects in the present report.

The North Wind and the Sun: Pediatric Antimicrobial Stewardship Program Combining Restrictive and Persuasive Approaches in Hematology-Oncology Ward and Hematopoietic Stem Cell Transplant Unit.

BACKGROUND: The Japanese government's goal for the reduction of antimicrobial consumption is two-thirds of the 2013 rate by 2020. While the antimicrobial stewardship programs (ASPs) are essential in health care facilities, ASP data on pediatric hematology-oncology and hematopoietic stem cell transplant (HSCT) patients are limited. Our aim was to evaluate the impact of restrictive and persuasive ASP on immunocompromised children. METHODS: The ASP for hematology-oncology and HSCT patients at Tokyo Metropolitan Children's Medical Center was assessed. Phase 1 was a postprescriptive review of carbapenem conducted between April 2010 and September 2011. Phase 2 consisted of the preauthorization of carbapenem, prospective audit with feedback, a weekly luncheon meeting among physicians, consensus on febrile neutropenia management, and implementation of viral molecular diagnostics between October 2011 and September 2015. Both phases were compared for day-of-therapy per 1,000 patient-days, cost of intravenous antimicrobial agents, average hospitalization duration, all-cause mortality, infection-related mortality at 30 days, and appropriateness of empirical treatment of bacteremia. RESULTS: The ASP did not differ from phase 1 to phase 2 in terms of average hospitalization length, mortality rate, or appropriateness of empirical treatment for bacteremia. Day-of-therapies of cefepime, piperacillin/tazobactam, meropenem, vancomycin, liposomal amphotericin B, and fosfluconazole decreased by 20%, 45%, 57%, 38%, 85% and 44%, respectively (P < 0.05). The total cost of antibiotic and antifungal agents decreased by 27%, for a savings of $59,905 USD annually. CONCLUSION: Restrictive and persuasive ASP in the hematology-oncology ward and the HSCT unit safely decreased the use of antibacterial and antifungal agents.

Antimicrobial Stewardship Program in a Pediatric Intensive Care Unit.

We conducted an antimicrobial stewardship program in a pediatric intensive care unit. An interrupted time-series analysis revealed a significant reduction in level and trend of days of therapy per 1000 patient-days for antipseudomonal agents. No increase in adverse patient outcomes was found.

Sustained pediatric antimicrobial stewardship program with consultation to infectious diseases reduced carbapenem resistance and infection-related mortality.

OBJECTIVE: The impact of pediatric antimicrobial stewardship programs (ASP) on antimicrobial resistance (AMR) remains largely unknown. This study aimed to evaluate the AMR for carbapenem of Gram-negative bacilli (GNB) and carbapenem use with infectious diseases consultation after the implementation of an ASP. METHODS: This quasi-experimental study was conducted at Tokyo Metropolitan Children's Medical Center in Japan. The pre- and post-intervention periods were April 2010 to September 2011 and October 2011 to March 2017, respectively. The pre-intervention phase consisted of consultations with the infectious diseases service alone. The ASP was implemented during the post-intervention phase. The carbapenem resistance rates of GNB were calculated. The correlation between carbapenem resistance rates and carbapenem day of therapy (DOT) was examined. The outcome metrics were compared by average length of hospitalization, all-cause mortality, and infection-related mortality. RESULTS: A positive correlation was observed between the carbapenem resistance rate in Pseudomonas aeruginosa and DOT (0.76, p=0.04). The carbapenem resistance rate in P. aeruginosa (p<0.01) and DOT (p<0.01) decreased significantly in the post-intervention period. The length of hospitalization (p<0.01) and infection-related mortality (p=0.05) decreased in the post-intervention period. CONCLUSIONS: A sustained ASP with additional consultation with the infectious disease service reduced carbapenem use and resistance in P. aeruginosa, leading to favorable outcomes in terms of length of hospitalization and infection-related mortality.

Susceptibilities to antiseptic agents and distribution of antiseptic-resistance genes qacA/B and smr of methicillin-resistant Staphylococcus aureus isolated in Asia during 1998 and 1999.

Many antiseptic agents are used in hygienic handwashes in the prevention of nosocomial infections by methicillin-resistant Staphylococcus aureus (MRSA). The plasmid-borne genes qacA/B and smr confer resistance to cationic antiseptic agents in S. aureus. In this study, the susceptibilities for dyes and antiseptic agents (e.g. acriflavine, acrinol, benzalkonium chloride, benzethonium chloride, chlorhexidine digluconate and alkyldiaminoethylglycine hydrochloride) of 894 isolates of MRSA collected from 11 Asian countries (South Korea, China, the Philippines, Singapore, Vietnam, Thailand, Indonesia, India, Sri Lanka, Saudi Arabia and Japan) between 1998 and 1999 were examined. In addition, the distributions of the antiseptic-resistance genes qacA/B and smr were studied by PCR. Among the Asian MRSA isolates 57.7% (516/894) were acriflavine-resistant. The smr gene was detected in 31.6% (12/38) of MRSA isolates from India but only in 1.9% (16/856) of all the isolates from other Asian countries. MRSA with qacA/B comprised 41.6% (372/894) of the isolates across Asia. In addition, PFGE was performed to type the MRSA and grouped the tested 30 MRSA isolates with qacA/B into 21 PFGE types. The results indicated that qacA/B is functionally the most important gene mediating antiseptic resistance in the MRSA strains of Asia and that a specific MRSA with qacA/B was not prevalent in Asia but qacA/B were widely spread among MRSA of Asia, while the geographical distribution of smr is more limited.

Molecular weight segregation on surfaces of polyethylene blended films as estimated from nanoscratch tests using scanning probe microscopy.

Nanoscratch tests using scanning probe microscopy (SPM) were performed on films prepared from two polyethylene (PE) materials polymerized by using a metallocene catalyst system with different molecular weights (MWs). Blended samples were prepared by dissolving both PE materials at various ratios in hot p-xylene. The pure and blended samples were compression molded into films at 180 degrees C for different holding times in the molten state. The results of SPM nanoscratch tests with an applied load of 30 nN indicated that the lower-MW surface could be easily plowed with wear debris but the higher-MW surface was less deformed. However, the deformation pattern of the blended film surface was similar to that of the lower-MW surface. These results suggest that MW segregation occurs during holding in the molten state as lower-MW components rise to the film surface.