Harnweginfektionen – Aktuelle Neuerungen in der Urindiagnostik

Zusammenfassung

Goldstandard in der Diagnostik einer Harnwegsinfektion (HWI) ist die Urinkultur. Diese dient neben der Erregeridentifikation, der Quantifizierung und ist die Grundlage der Resistenzprüfung. Nachteilig ist jedoch, dass bis zu 80% der eingesandten Urinproben negativ sind. Die aktuell zur Resistenzprüfung zugelassenen Techniken sind alle kulturbasiert und haben den Nachteil, sehr langsam zu sein. In Bezug auf das urologische Fachgebiet erschwert die Resistenzentwicklung uropathogener Erreger die optimale Gabe von antimikrobiellen Substanzen nicht nur in der Therapie von Harnwegsinfektionen sondern auch in der Prophylaxe vor endourologischen und offenen Eingriffen. In diesem Zusammenhang ist eine schnelle mikrobiologische Erregeridentifikation inklusive zeitnahem Eingang der Resistenzprüfung erstrebenswert. In dieser Übersicht werden alternative Techniken (Flowzytometrie, PCR-basierte Techniken, MALDI-TOF MS und Mikrokalorimetrie) zur Urinkultur vorgestellt und ihre Vor- und Nachteile diskutiert.

Abstract

Urine culture (UC) confirms the diagnosis of urinary tract infection (UTI) and is still considered the diagnostic ‘gold standard’ for pathogen identification, quantification and resistance testing. However, up to 80% of samples will not yield bacterial growth. Different techniques are currently approved for resistance testing. However, all of them are culture based and have the disadvantage of being very slow. In the field of urology, the development of drug resistance of uropathogens complicates the optimal administration of antimicrobial agents not only in the treatment, but also in the prevention of UTI before endourological and open surgical procedures. In this context, rapid identification of microbiological agents, including timely antimicrobial resistance testing (ART) is desirable. This overview presents alternative techniques (flow cytometry, PCR-based techniques, MALDI-TOF MS and microcalorimetry) to urine culture and discusses their advantages and disadvantages.

Schlüsselwörter

Harnwegsinfektion - Urinkultur - MALDI-TOF MS - Mikrokalorimetrie - Antibiogramm

Key words

urinary tract infection - urine culture - MALDI-TOF MS - microcalorimetry - antibiogram

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