V Nordberg1, K Jonsson2, C G Giske3, A Iversen3, O Aspevall4, B Jonsson5, A Camporeale6, M Norman7, L Navér7. 1. Department of Neonatal Medicine, Karolinska University Hospital, Sweden; Department of Clinical Science, Intervention and Technology (CLINTEC), Division of Paediatrics, Karolinska Institutet, Sweden. Electronic address: viveka.nordberg@ki.se. 2. Department of Neonatal Medicine, Karolinska University Hospital, Sweden. 3. Department of Clinical Microbiology, Karolinska University Hospital, Sweden; Department of Laboratory Medicine, Division of Clinical Microbiology, Karolinska Institutet, Sweden. 4. The Public Health Agency of Sweden, Stockholm, Sweden. 5. Department of Neonatal Medicine, Karolinska University Hospital, Sweden; Department of Women's and Children's Health, Karolinska Institutet, Sweden. 6. Department of Laboratory Medicine, Division of Clinical Microbiology, Karolinska Institutet, Sweden. 7. Department of Neonatal Medicine, Karolinska University Hospital, Sweden; Department of Clinical Science, Intervention and Technology (CLINTEC), Division of Paediatrics, Karolinska Institutet, Sweden.
Abstract
OBJECTIVES: To analyse Klebsiella pneumoniae (KP) isolates from an outbreak of extended-spectrum β-lactamase (ESBL)-producing KP and Escherichia coli (EC) among infants admitted to neonatal intensive care units and to determine the duration of the intestinal colonization. METHODS: We performed a prospective cohort study of intestinal ESBL-KP/ESBL-EC colonized neonates after a 5-month outbreak in two neonatal intensive care units. Whole genome sequencing, multilocus sequence typing, core genome multilocus sequence typing, pulsed-field electrophoresis and PCR for blaCTX-M were performed on the first isolates. Stool cultures were performed every second month after discharge until 2 years after discharge and at 5 years of age. The last positive samples were analysed with pulsed-field gel electrophoresis and PCR for blaCTX-M. The intestinal relative dominance of ESBL-producing Enterobacteriaceae was determined. RESULTS: Thirteen of 17 patients colonized with ESBL-KP/ESBL-EC survived. Isolates from 16 of 17 patients were available for analysis and featured the same strain type of ESBL-KP: sequence type 101. The strain had capsule type K29 and harboured blaCTX-M-15. The virulence genes irp1, irp2, iutA, kfu and mrk were detected in all isolates. The median length of colonization was 12.5 months (range, 5-68 months). After 2 years, two of 13 patients were carriers of ESBL-KP and one of 13 of ESBL-EC. At 5 years of age, one neonate was colonized with ESBL-EC. No infant experienced an ESBL-KP/EC-infection during follow-up. CONCLUSIONS: Two years after discharge, almost one fourth of the study participants were ESBL/KP-EC carriers. ESBL-KP sequence type 101 persisted in two of 13 children for 23 to 26 months. One patient was colonized with ESBL-EC at age 5 years.
OBJECTIVES: To analyse Klebsiella pneumoniae (KP) isolates from an outbreak of extended-spectrum β-lactamase (ESBL)-producing KP and Escherichia coli (EC) among infants admitted to neonatal intensive care units and to determine the duration of the intestinal colonization. METHODS: We performed a prospective cohort study of intestinal ESBL-KP/ESBL-EC colonized neonates after a 5-month outbreak in two neonatal intensive care units. Whole genome sequencing, multilocus sequence typing, core genome multilocus sequence typing, pulsed-field electrophoresis and PCR for blaCTX-M were performed on the first isolates. Stool cultures were performed every second month after discharge until 2 years after discharge and at 5 years of age. The last positive samples were analysed with pulsed-field gel electrophoresis and PCR for blaCTX-M. The intestinal relative dominance of ESBL-producing Enterobacteriaceae was determined. RESULTS: Thirteen of 17 patients colonized with ESBL-KP/ESBL-EC survived. Isolates from 16 of 17 patients were available for analysis and featured the same strain type of ESBL-KP: sequence type 101. The strain had capsule type K29 and harboured blaCTX-M-15. The virulence genes irp1, irp2, iutA, kfu and mrk were detected in all isolates. The median length of colonization was 12.5 months (range, 5-68 months). After 2 years, two of 13 patients were carriers of ESBL-KP and one of 13 of ESBL-EC. At 5 years of age, one neonate was colonized with ESBL-EC. No infant experienced an ESBL-KP/EC-infection during follow-up. CONCLUSIONS: Two years after discharge, almost one fourth of the study participants were ESBL/KP-EC carriers. ESBL-KP sequence type 101 persisted in two of 13 children for 23 to 26 months. One patient was colonized with ESBL-EC at age 5 years.
Authors: Santosh K Bikkarolla; Viveka Nordberg; Fredrika Rajer; Vilhelm Müller; Muhammad Humaun Kabir; Sriram Kk; Albertas Dvirnas; Tobias Ambjörnsson; Christian G Giske; Lars Navér; Linus Sandegren; Fredrik Westerlund Journal: mBio Date: 2019-07-09 Impact factor: 7.867