Retrospective audit of antibiotic use in a university general pediatrics department using hospital pharmacy dispensing data.

Antibiotics are among the most frequently prescribed drugs in children's hospitals, which is why regular monitoring of antibiotic use in hospitals is of great importance. This retrospective audit (60 months, January 2014 - December 2018) analyzes the antibiotic consumption at a university inpatient department of general pediatrics including neonatal and pediatric intensive care based on pharmacy dispensing data in units of grams per 100 patient days and in Defined Daily Doses per 100 patient days. The results provide potential targets for Antibiotic Stewardship interventions. Conversely, this audit elicits methodological limitations of the method of antibiotic surveillance in pediatrics recommended by the Robert Koch Institute, Berlin.

Meropenem Use in Pediatric Oncology - Audit on Indication, Appropriateness and Consumption Comparing Patient Derived and Pharmacy Dispensing Data.

BACKGROUND: Meropenem is an important second- or third-line antibiotic in pediatric cancer patients with febrile neutropenia (FN). Concise utilization data of meropenem in this setting is limited. It remains unclear how drug dispensing data from the hospital pharmacy correlate with data derived from patients' files. METHODS: Retrospective audit of meropenem-consumption in a University-affiliated pediatric oncology center in days of therapy (DOT)/100 inpatient days. The individual indication for meropenem was critically reviewed. The real consumption (in g/100 inpatient days) was compared with the drug amounts dispensed by the hospital pharmacy (in gram and in defined daily doses (DDD)/100 inpatient days). All patients receiving at least one dose of meropenem from 1st of April 2016 until the 30th of June 2018 were included. RESULT: Of 235 consecutive patients, 45 (19%) received meropenem, comprising 57 FN events. The probability of receiving at least one dose of meropenem was significantly higher in patients with ALL, AML, NHL and certain CNS tumors. Preceding the use of meropenem, only 5% of patients were known to be colonized with multidrug-resistant Gram-negative pathogens. Meropenem was administered as first-line treatment in 26% of all meropenem cycles, in 74% of all FN events with meropenem, Piperacillin-Tazobactam was used for initial treatment. In 5 of 57 FN events (8.8%), initial blood cultures yielded a Gram-negative pathogen. Concerning definite treatment, appropriate alternatives to meropenem with a smaller spectrum of activity would have been available in 4 cases, but a de-escalation was not performed. The median length of therapy in the meropenem group was 6 days, the corresponding median for days of therapy (DOT) was 12 days. This corresponds with combination therapy in 56% of all meropenem treatments, mostly with teicoplanin. On average, drug dispensing data from the hospital pharmacy were 1.53 times higher than real use (relying on patients' data) without a significant correlation. A higher Case-mix Index positively correlated with meropenem-consumption. CONCLUSION: The use of meropenem should become a target of antibiotic stewardship programs in order to restrict its use to certain indications and preserve its outstanding role as second- or third-line antibiotic in this vulnerable population. Irrespective of the metrics used (g or DDD/100 inpatient days), pharmacy dispensing data do not accurately depict real patient-derived data concerning meropenem use in pediatric cancer patients.

68 Ga-PSMA-PET for radiation treatment planning in prostate cancer recurrences after surgery: Individualized medicine or new standard in salvage treatment.

BACKGROUND: 68 Ga-PSMA-PET imaging is a novel promising diagnostic tool to locate early biochemical failure after radical prostatectomy (RP) in prostate cancer (PC) patients. Exact knowledge of the relapse location may result in changes of the therapy concept aside from changes to the TNM stage. To gain data for this approach, we evaluated PC patients receiving 68 Ga-PSMA-PET imaging before salvage radiotherapy (RT). METHODS AND MATERIALS: In this study, 100 patients with biochemical failure after RP± prior RT who underwent 68 Ga-PSMA PET/CT or PET/MRI were evaluated undergoing salvage RT in our department. We analyzed TNM staging changes due to 68 Ga-PSMA-PET imaging and its influence on RT planning and treatment. RESULTS: Uptake indicative for tumor recurrence in 68 Ga-PSMA-PET was found in 76% of the patients with biochemical recurrent PC. Median PSA level was 1.0 ng/mL (range 0.12-14.7 ng/mL). Of these, 80% showed no morphological correlate in the corresponding CT or MRI. A 43% of all patients experienced a change in TNM stage due to 68 Ga-PSMA-PET imaging. Patients had changes from Tx to rcT+ (28%), 12% from pN0 to rcN1, 1% from pN0/cM0 to rcM1a, and 8% from cM0 to rcM1b. Due to the additional knowledge of 68 Ga-PSMA-PET imaging, initial planned RT planning was adapted in 59% of all cases. An additional simultaneous integrated boost (SIB) to the prostate bed or lymph nodes was given to 32% and 63%, respectively. Ten patients received stereotactic body RT (SBRT) to single bone metastases. CONCLUSION: 68 Ga-PSMA-PET imaging showed a high clinical impact on staging and RT management in patients with biochemically recurrent PC, even at low serum PSA levels. With 43% changes in staging and 59% in radiotherapy planning 68 Ga-PSMA-PET could lead to an indispensable tool in guiding radiation treatment in recurrent PC.

Integration of (68)Ga-PSMA-PET imaging in planning of primary definitive radiotherapy in prostate cancer: a retrospective study.

BACKGROUND: Prostate cancer (PC) is one of the most commonly treated cancer entities with radiation therapy (RT). Risk group-adapted treatment and avoidance of unnecessary toxicities relies primarily on accurate tumor staging. Thus, the introduction of prostate-specific membrane antigen (PSMA) in diagnosis and treatment of PC is a highly interesting development in radiation oncology of urologic tumors. The present work is to evaluate the integration of (68)Ga-PSMA-PET imaging into standard radiation planning of primary definitive treatment of PC and to determine the impact of PSMA imaging on tumor staging. METHODS: The data of 15 patients treated for PC between August 2013 and April 2015 were evaluated. Treatment planning included (68)Ga-PSMA-PET imaging. We analyzed whether the use of PSMA-imaging led to a change of the TNM stage and if it influenced the RT treatment approach or the target volume, due to changes in the gross tumor volume (GTV) or clinical target volume (CTV), in the final treatment plan. RESULTS: In 53.3 % of the analyzed patients a change occurred in the TNM stage based on (68)Ga-PSMA-PET examination. The RT concept changed in 33.3 % of all patients, leading to relevant changes in the planning target volume. Among these, an additional irradiation of the pelvic lymph drainage due to tracer uptake in lymph nodes was performed in 25 %. Furthermore, boost volumes of PET-positive lymph nodes were added in 80 % of these cases. A down staging due to the (68)Ga-PSMA-PET examination occurred in 13.3 % of all cases. CONCLUSIONS: The integration of (68)Ga-PSMA-PET-imaging into the RT treatment planning process can be useful for detailed target volume planning. The performance of a (68)Ga-PSMA-PET frequently leads to changes in the TNM stage, altering the RT treatment regimen and the target volume. A prospective trial is underway to evaluate the impact of (68)Ga-PSMA-PET based treatment planning on outcome.

Chemical biology of DNA polymerases: from selectivity to new functions.

DNA polymerases are involved in all DNA synthesis occurring in nature. Furthermore, DNA polymerases are the workhorses in numerous important molecular biological core technologies like the ubiquitous polymerase chain reaction (PCR), cDNA cloning, genome sequencing and nucleic acids based diagnostics. In order to identify DNA polymerase mutants with altered properties, we set up an efficient high through put setup to rapidly screen libraries of DNA polymerase mutants in automated parallel fashion and identified entities with significantly increased selectivity. Furthermore, our results indicate a rational to generally increase DNA polymerase selectivity as we demonstrate for several enzymes from different DNA polymerase families. Additionally, we show that the generation of a new DNA polymerase function is achievable through iterative screening of small libraries of DNA polymerase derived by randomization of the respective genes. We demonstrate that the identified mutants find immediate applications and provide the basis for the development of new means for diagnostic technologies.