Use of drugs in patients with renal insufficiency. Workshop report

Calculated parenteral initial treatment of bacterial infections: Infections of the kidneys and the genito-urinary tract

This is the eighth chapter of the guideline "Calculated initial parenteral treatment of bacterial infections in adults - update 2018" in the 2nd updated version. The German guideline by the Paul-Ehrlich-Gesellschaft für Chemotherapie e.V. (PEG) has been translated to address an international audience. The chapter deals with the treatment of more severe infections of the kidney and the urogenital tract, including urosepsis. Recommendations for empiric and targeted antibacterial treatment are given.

Dose adjustment guidelines for medications in patients with renal impairment: how consistent are drug information sources?

BACKGROUND

It is known that patients with renal disease are often administered inappropriate dosages of drugs. A lack of quantitative data in the available drug information sources and inconsistency in dosing information may augment the problem of dosing error.

AIMS

To determine the concordance among five drug information sources regarding the dosing recommendations provided for drugs considered problematic in patients with renal impairment and to determine the consistency among the sources regarding the definition of renal impairment and categorisation of chronic kidney disease.

METHODS

Five standard drug information sources were reviewed for 61 drugs recommended to be used with caution in renal impairment. Information on recommendations for dosage adjustment in renal impairment was extracted and analysed. Further, the definition and classification of renal impairment were recorded. The recommendation for each drug was coded into six different categories and the intersource reliability was calculated.

RESULTS

Only slight agreement was observed among the sources (Fleiss Kappa: 0.3). Qualitative data were not well defined, and there was a lack of consistency in quantitative values. Some drugs marked as contraindicated in one source were not mentioned as such in others. Also, drugs considered as not requiring dosage adjustment in one source had explicit recommendations in other sources. The definition and classification of renal impairment differed among the five information sources.

CONCLUSIONS

There should be an evidence-based approach to drug dosage adjustment in order to bring uniformity to the recommendations. Regular updating of the content of the drug information sources is also important.

Drug dosing in chronic kidney disease

Patients with chronic kidney disease (CKD) are at high risk for adverse drug reactions and drug-drug interactions. Drug dosing in these patients often proves to be a difficult task. Renal dysfunction-induced changes in human pathophysiology regularly results may alter medication pharmacodynamics and handling. Several pharmacokinetic parameters are adversely affected by CKD, secondary to a reduced oral absorption and glomerular filtration; altered tubular secretion; and reabsorption and changes in intestinal, hepatic, and renal metabolism. In general, drug dosing can be accomplished by multiple methods; however, the most common recommendations are often to reduce the dose or expand the dosing interval, or use both methods simultaneously. Some medications need to be avoided all together in CKD either because of lack of efficacy or increased risk of toxicity. Nevertheless, specific recommendations are available for dosing of certain medications and are an important resource, because most are based on clinical or pharmacokinetic trials.