Title : Aetiology of hospital-acquired gram negative bacteraemias over the COVID-19 pandemic, a single NHS trust experience, UK
Abstract:
Gram negative bacteria (GNB) are the most common cause of healthcare-associated bacteraemias, most commonly caused by Escherichia coli, Klebsiella and Pseudomonas. GNB carry significant mortality and morbidity, therefore prompt and appropriate antibiotic therapy is important. However, there are also high rates of GNB resistance, posing a significant public health concern. Nationally, all NHS trusts are mandated to report their rates of GNB to the UK Health Security Agency as part of their plan to reduce incidence by 2025. The COVID-19 pandemic disrupted healthcare delivery from March 2020, with higher rates of GNB being recorded nationally.
We retrospectively analysed three years of GNB data, using a five month sample of April to August each year, from University Sussex Hospital NHS Foundation Trust east hospitals. Looking at hospital-acquired data (defined as blood culture taking on or after day 3 of admission), we analysed the demographics, incidence and resistance patterns of GNB using online medical and microbiology records. Data collection and analysis took place on Microsoft Excel.
From 2019 to 2021, there were 29, 27 and 19 cases in each time five month sample respectively. The median age of patients was 78, 64 and 73 years. Positive blood cultures were taken later into admission during 2020 (14 vs 8 and 9 days) with an increased length of median hospital stay (33 vs 23 and 24 days). The source of each GNB can be seen in table 1 (created as per national record keeping guidelines), with 2020 attributing a higher proportion of cases to ‘other’, which includes iatrogenic procedures and surgical operations. Mortality rates were highest in 2020 (26.9 vs 21.4 and 21.1%), although not significantly, with transmission in neonates a risk factor. 2020 also carried the highest rate of multi-drug resistant GNB (22%), both within and outside of an intensive care setting.
Our data shows an increase in the mortality rate and antibiotic resistance in GNB during the height of the COVID-19 pandemic that returned to baseline the following year. Likely due to a reduction in elective activity and fewer bed days. Ongoing evaluation of GNB aetiology, particularly resistance patterns, is vital to improve health outcomes.
Table 1: incidence and likely source of GNB over a five month period across three years.
|
Overall GNBs |
Gastrointestinal |
Hepatobiliary |
Urine |
Chest |
Other |
Unknown |
|
N (%) |
N (%) |
N (%) |
N (%) |
N (%) |
N (%) |
|
|
2019 |
3 (10.3) |
4 (13.8) |
5 (17.2) |
7 (24.1) |
1 (3.4) |
9 (31.0) |
|
2020 |
1 (3.7) |
4 (14.8) |
4 (14.8) |
1 (3.7) |
9 (33.3) |
5 (18.5) |
|
2021 |
0 (0.0) |
4 (21.0) |
2 (10.5) |
2 (10.5) |
3 (15.8) |
8 (42.1) |
Audience take away:
- Reducing incidence of GNB must remain a healthcare research and education priority.
- The COVID pandemic led to an increase in mortality and antibiotic resistance from GNB.
- Resistance pattern monitoring and antimicrobial stewardship is essential for all healthcare workers.
