Introduction: Use of higher than standard doses of amikacin (AMK) has been proposed during sepsis, especially to treat less susceptible bacterial strains. However, few data are available on drug concentrations during prolonged therapy and on potential adverse events related to this strategy. Methods: Sixty-three critically ill patients who required AMK administration for the treatment of severe infection were included in this study. After a loading dose (LD, 18 to 30 mg/kg), the daily regimen was adapted using therapeutic drug monitoring (TDM) of both peak (Cpeak) and trough (Cmin) concentrations. Target concentrations had to give a ratio of at least 8 between Cpeak and the minimal inhibitory concentration (MIC) of the isolated pathogen. A Cmin >5 mg/L was considered as potentially nephrotoxic. We recorded clinical and microbiological responses, the development of acute kidney injury (AKI) during therapy and ICU mortality. Results: The median AMK LD was 1500 (750 to 2400) mg, which resulted in a Cpeak/MIC ≥8 in 40 (63%) patients. Increasing the dose in the 23 patients with a Cpeak/MIC 5mg/L after the LD, notably in the presence of altered renal function at the onset of therapy, needing prolongation of drug administration. Overall, only 11 patients (17%) required no dose or interval adjustment during AMK therapy. Clinical cure (32/37 (86%) vs. 16/23 (70%), P = 0.18)) and microbiological eradication (29/35 (83%) vs. 14/23 (61%), P = 0.07) were higher in patients with an initial optimal Cpeak/MIC than in the other patients. The proportion of patients with clinical cure significantly improved as the Cpeak/MIC increased (P = 0.006). Also, increased time to optimal Cpeak was associated with worse microbiological and clinical results. AKI was identified in 15 patients (24%) during AMK therapy; 12 of these patients already had altered renal function before drug administration. Survivors (n = 47) had similar initial Cpeak/MIC ratios but lower Cmin values compared to nonsurvivors. Conclusions: TDM resulted in adjustment of AMK therapy in most of our septic patients. Early achievement of an optimal Cpeak/MIC ratio may have an impact on clinical and microbiological responses, but not on outcome. In patients with impaired renal function prior to treatment, AMK therapy may be associated with a further decline in renal function.
Antibiotics as antibacterial drugs have saved many lives, but have also become a victim of their own success. Their widespread abuse reduces their anti-infective effectiveness and causes the development of bacterial resistance. Moreover, irrational antibiotic therapy contributes to gastrointestinal dysbiosis, that increases the risk of the development of many diseases, including neurological and psychiatric. One of the potential options for restoring homeostasis is the use of oral antibiotics that are poorly absorbed from the gastrointestinal tract (e.g., rifaximin alfa). Thus, antibiotic therapy may exert neurological or psychiatric adverse drug reactions which are often considered to be overlooked and undervalued issues. Drug-induced neurotoxicity is mostly observed after beta-lactams and quinolones. Penicillin may produce a wide range of neurological dysfunctions, including encephalopathy, behavioral changes, myoclonus or seizures. Their pathomechanism results from the disturbances of gamma-aminobutyric acid-GABA transmission (due to the molecular similarities between the structure of the β-lactam ring and GABA molecule) and impairment of the functioning of benzodiazepine receptors (BZD). However, on the other hand, antibiotics have also been studied for their neuroprotective properties in the treatment of neurodegenerative and neuroinflammatory processes (e.g., Alzheimer’s or Parkinson’s diseases). Antibiotics may, therefore, become promising elements of multi-targeted therapy for these entities.
1 February 2012 in International Journal of Antimicrobial Agents
Background. Postoperative nausea and vomiting (PONV) is a common complication after anesthesia and surgery. Ondansetron is one of the most widely used drugs in the prophylaxis of PONV and is extensively metabolized in humans. In vitro metabolism studies have shown that ondansetron is a substrate for human hepatic cytochrome P450 enzymes. The cytochrome P450 (human hepatic cytochrome [CYP]) 2D6 inhibitor quinidine reduced in vitro hydroxylation of ondansetron, which indicates the important role of CYP2D6 in ondansetron metabolism. Genotyping these alleles allows the prediction of the extensive metabolizer (EM) and poor metabolizer (PM) phenotypes with approx. 90-96% accuracy. Objectives. The aim of our study wasto evaluate whether the pharmacological prevention of PONV with ondansetron depends on the most common CYP2D6 alleles (CYP2D6*1, *3, *4, *5, and NxN [multiplication gene]). Material and methods. Genotyping for the defective CYP2D6*3, CYP2D6*4 and CYP2D6*5 alleles among 93 surgical female patients was performed by polymerase chain reaction amplification and restriction fragment length polymorphism (PCR-RFLP). Results. The genetically defined EMs and ultrarapid metabolizers (UMs) of CYP2D6 had a statistically significant (p < 0.02) higher frequency of nausea and vomiting after strumectomy (33.3%) than intermediate metabolizers (IMs) (10.3%) and PMs (0%). The relative risk (odds ratio [OR]) of PONV occurrence was 5 times higher for EMs/UMs than IMs/PMs. Conclusions. Our results suggest that PONV treatment with ondansetron could be improved by basic, widely available and inexpensive PCR-RFLP genetic tests.
The perception of acute heart failure (AHF) as a single entity is increasingly outdated, as distinct patient profiles can be discerned. Key heart failure (HF) studies have previously highlighted the difference in both the course and prognosis of de novo AHF and acute decompensated chronic HF (ADHF). Accordingly, distinct AHF profiles with differing underlying pathophysiologies of disease progression can be shown. We compared a range of selected biomarkers in order to better describe the profile of de novo AHF and ADHF, including the inter alia—serum lactate, bilirubin, matrix metallopeptidase 9 (MMP-9), follistatin, intercellular adhesion molecule 1 (ICAM-1), lipocalin and galectin-3. The study comprised 248 AHF patients (de novo = 104), who were followed up for one year. The biomarker data of the de novo AHF and ADHF profiles was then compared in order to link biomarkers to their prognosis. Our study demonstrated that, although there are similarities between each patient profile, key biomarker differences do exist—predominantly in terms of NTproBNP, serum lactate, bilirubin, ICAM-1, follistatin, ferritin and sTfR (soluble transferrin receptor). ADHF tended to have compromised organ function and higher risks of both one-year mortality and composite endpoint (one-year mortality or rehospitalization for heart failure) hazard ratios (HR) (95% CI): 3.4 (1.8–6.3) and 2.8 (1.6–4.6), respectively, both p < 0.0001. Among the biomarkers of interest: sTfR HR (95% CI): 1.4 (1.04–1.8), NGAL(log) (neutrophil gelatinase-associated lipocalin) HR (95% CI): 2.0 (1.3–3.1) and GDF-15(log) (growth/differentiation factor-15) HR (95% CI): 4.0 (1.2–13.0) significantly impacted the one-year survival, all p < 0.05.
14 November 2018 in European Journal of Clinical Pharmacology
To evaluate the relationship between total and free MPA pharmacokinetic (PK) parameters and renal outcome markers, and to verify whether conducting therapeutic drug monitoring (TDM) in lupus nephritis (LN) patients would be of value in routine clinical practice.