antibioticsАнтибиотики и ХимиотерапияAntibiot Khimioter = Antibiotics and Chemotherapy0235-2990ООО «Издательство ОКИ»10.37489/0235-2990-2024-69-3-4-42-50FSGBXGantibiotics-1124Research ArticleЭКСПЕРИМЕНТАЛЬНЫЕ ИССЛЕДОВАНИЯEXPERIMENTAL STUDIESПрогнозирование эффективности азтреонама в отношении Klebsiella pneumoniae по результатам оценки чувствительности бактерии к антибиотику при увеличенном инокулятеPrediction of Aztreonam Effectiveness Against Klebsiella pneumoniae Based on the Results of Antimicrobial Susceptibility Testing with Increased Inoculumhttps://orcid.org/0000-0002-2107-8259АлиеваК. Н.AlievaK. N.

Алиева Камилла Натиговна — к. б. н., научный сотрудник лаборатории фармакокинетики и фармакодинамики

Москва

ResearcherID: AAG-68692019. Scopus Author ID: 57197836617

Kamilla N. Alieva — Ph. D. in Biology, Researcher at the Laboratory of Pharmacokinetics and Pharmacodynamics

Moscow

ResearcherID: AAG-6869-2019. Scopus Author ID: 57197836617

qvimqwem@yandex.ruhttps://orcid.org/0000-0002-7588-1733ГоликоваМ. В.GolikovaM. V.

Голикова Мария Владимировна — к. б. н.

Москва

. ResearcherID: O-7873-2016. Scopus Author ID: 56497807500

Maria V. Golikova — Ph. D. in Biology

Moscow

ResearcherID: O-7873-2016. Scopus Author ID: 56497807500 

https://orcid.org/0009-0008-9953-135XКондратьеваД. А.KondratievaD. A.

Кондратьева Дарья Андреевна

Москва

Daria A. Kondratieva

Moscow

https://orcid.org/0000-0002-2092-5559КузнецоваА. А.KuznetsovaA. A.

Кузнецова Анастасия Алексеевна

Москва

Anastasiya A. Kuznetsova

Moscow

ФГБНУ «Научно-исследовательский институт по изысканию новых антибиотиков им. Г. Ф. Гаузе» (ФГБНУ «НИИНА»)РоссияGause Institute of New AntibioticsRussian Federation202421062024693-44250Copyright © Алиева К.Н., Голикова М.В., Кондратьева Д.А., Кузнецова А.А., 20242024Алиева К.Н., Голикова М.В., Кондратьева Д.А., Кузнецова А.А.Alieva K.N., Golikova M.V., Kondratieva D.A., Kuznetsova A.A.Данная работа распространяется под лицензией Creative Commons Attribution 4.0.This work is licensed under a Creative Commons Attribution 4.0 License.https://www.antibiotics-chemotherapy.ru/jour/article/view/1124Актуальность

Актуальность. Минимальная подавляющая концентрация (МПК) антибиотика не позволяет прогнозировать риск развития устойчивости бактерий под воздействием антибиотика из-за малой выборки бактерий. Минимальная подавляющая концентрация антибиотика при увеличенном инокуляте (МПКВИ) может стать подходящим для такой цели параметром за счёт увеличенной выборки и простоты определения.

Цель

Цель. Исследование направлено на оценку потенциала использования МПКВИ как параметра для прогнозирования развития устойчивости Klebsiella pneumoniae к азтреонаму.

Методы

Методы. Оценили значения МПК и МПКВИ азтреонама в отношении двух штаммов K. pneumoniae методом микроразведений (объём 0,2 мл; инокулят 5×105 и 5×107 КОЕ/мл, соответственно) и сопоставили результаты с эффектом азтреонама в динамической системе in vitro, где моделировали режим применения азтреонама 2 г каждые 8 ч в виде 2-часовой инфузии в течение 5 сут.

Результаты

Результаты. Эффективность азтреонама в отношении K. pneumoniae, наблюдаемая в динамической системе, согласовывалась со значениями МПКВИ после уточнения результатов по оценке жизнеспособности бактерий. При визуальной оценке значения МПКВИ были сильно завышены из-за избыточной мутности вследствие образования филаментных форм бактерии под действием азтреонама.

Заключение

Заключение. Параметр МПКВИ можно использовать для прогнозирования развития устойчивости K. pneumoniae к азтреонаму при оценке значений данного параметра по численности жизнеспособных клеток, но не по визуальной границе роста. 

Background

Background. The minimum inhibitory concentration (MIC) does not predict the risk of antibacterial resistance development due to a small sample of tested bacteria. Minimum inhibitory concentration at an increased inoculum (MICHI) may become a suitable parameter for this purpose as a sample of tested bacteria is larger while the method of determination remains easy.

The aim of the study was to evaluate the potential of using MICHI as a parameter for predicting the resistance development in Klebsiella pneumoniae to aztreonam.

Methods

Methods. Aztreonam MIC and MICHI values were assessed against two strains of K. pneumoniae using the microdilution method (0.2 ml volume; inoculum of 5×105 and 5×107 CFU/ml, respectively) and compared the results with the effect of aztreonam in a dynamic in vitro model, in which  aztreonam regimen of 2 grams every 8 hours as a 2-hour infusion for 5 days was simulated.

Results

Results. The efficacy of aztreonam against K. pneumoniae observed in the dynamic model was consistent with the MICHIs values assessed based on bacterial viability. During the visual assessment, the MICHIs values were greatly overestimated due to excessive turbidity caused by the formation of filamentous forms of bacteria exposed to aztreonam.

Conclusions

Conclusions. The MICHI parameter can be used to predict the development of resistance in K. pneumoniae to aztreonam when assessing the values of this parameter by the number of viable cells, but not by the visual boundary of bacterial growth.

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The authors declare that there are no conflicts of interest present.