Risk factors for recurrent healthcare-facility associated Clostridioides difficile infection in a Swedish setting.

OBJECTIVE: The objectives were to determine the risk factors for recurrent healthcare facility-associated Clostridioides difficile infection (HCF-CDI) in a high CDI incidence, low antibiotic use setting and to determine if length of cefotaxime exposure is a risk factor for recurrent HCF-CDI. METHODS: The risk factors for recurrent HCF-CDI were evaluated with a retrospective nested case control study based on chart reading. The risk factors were evaluated univariately and multivariately. Length of risk antibiotic exposure was evaluated further in a subanalysis. RESULTS: Risk factors for recurrent HCF-CDI were renal insufficiency (25.4% of cases compared to 15.4% of controls p = 0.006) and metronidazole treatment of initial CDI episode (88.4% compared to 71.7% p = 0.01). Exposure to cefotaxime and risk for recurrent CDI showed a dose-dependent relationship (linear by linear p = 0.028). CONCLUSIONS: Renal insufficiency and metronidazole treatment were independent risk factors for recurrent HCF-CDI in our setting. The relationship between cefotaxime exposure and risk for recurrent HCF-CDI, dose-dependent, could be evaluated further in a setting with high cefotaxime use.

Environmental Contamination by Chlamydia trachomatis RNA Can Cause False-Positive Test Results in Clinical Samples.

ABSTRACT: An investigation of unexpected positive test results for Chlamydia trachomatis at a women's health clinic in Sweden revealed that samples were contaminated by RNA in the clinic. The risk for RNA contamination at a clinic has been postulated previously. We are, however, not aware that this has actually been demonstrated in practice.

Clostridioides difficile incidence related to in-hospital cephalosporin use: a tale of two highly comparable hospitals.

Background: Antibiotic treatment is a well-known risk factor for healthcare facility-associated Clostridioides (Clostridium) difficile infection (HCF-CDI). Antibiotic stewardship programmes (ASPs) targeting high-risk antibiotics have been shown to decrease HCF-CDI incidence. HCF-CDI incidence is high in Nordic countries despite relatively low antibiotic use in hospital. Objectives: To determine if HCF-CDI incidence was modified by a hospital ASP that restricted cephalosporin use. Methods: The effects of an ASP on HCF-CDI incidence were evaluated in a two-centre setting using a retrospective design. We exploited a strategy of both individual case ascertainment based on chart reviews and aggregated data from the hospitals. Cases were attributed to the antibiotics given prior to disease onset, in proportion to the number of DDDs used. Three periods were studied: 2007 (before the ASP), 2012 and 2015. Results: At the ASP hospital, cephalosporin use decreased by 87% and the number of HCF-CDI/1000 hospital admissions decreased significantly from 2.25 (2007) to 1.16 (2015) (P = 0.0014). The corresponding results at the non-ASP hospital showed a non-significant increase from 2.09 to 2.38. A high number of cases could be attributed to cephalosporins at both hospitals. The increased use of other broad-spectrum antibiotics, e.g. piperacillin/tazobactam, at the ASP hospital was not associated with offsetting increases in attributable HCF-CDI cases. Conclusions: Decreased use of cephalosporins is an effective strategy to decrease HCF-CDI incidence over time in a setting with high incidence and low antibiotic use.

National Surveillance for Clostridioides difficile Infection, Sweden, 2009-2016.

We report results from a national surveillance program for Clostridioides difficile infection (CDI) in Sweden, where CDI incidence decreased by 22% and the proportion of multidrug-resistant isolates decreased by 80% during 2012-2016. Variation in incidence between counties also diminished during this period, which might be attributable to implementation of nucleic acid amplification testing as the primary diagnostic tool for most laboratories. In contrast to other studies, our study did not indicate increased CDI incidence attributable the introduction of nucleic acid amplification testing. Our results also suggest that successful implementation of hygiene measures is the major cause of the observed incidence decrease. Despite substantial reductions in CDI incidence and prevalence of multidrug-resistant isolates, Sweden still has one of the highest CDI incidence levels in Europe. This finding is unexpected and warrants further investigation, given that Sweden has among the lowest levels of antimicrobial drug use.

Epidemiology of fungaemia in Sweden: A nationwide retrospective observational survey.

OBJECTIVES: To identify the epidemiology and antifungal susceptibilities of Candida spp. among blood culture isolates to identify the epidemiology and antifungal susceptibilities of Candida spp. among blood culture isolates in Sweden. METHODS: The study was a retrospective, observational nationwide laboratory-based surveillance for fungaemia and fungal meningitis and was conducted from September 2015 to August 2016. RESULTS: In total, 488 Candida blood culture isolates were obtained from 471 patients (58% males). Compared to our previous study, the incidence of candidaemia has increased from 4.2/100 000 (2005-2006) to 4.7/100 000 population/year (2015-2016). The three most common Candida spp. isolated from blood cultures were Candida albicans (54.7%), Candida glabrata (19.7%) and species in the Candida parapsilosis complex (9.4%). Candida resistance to fluconazole was 2% in C. albicans and between 0% and 100%, in non-albicans species other than C. glabrata and C. krusei. Resistance to voriconazole was rare, except for C. glabrata, C. krusei and C. tropicalis. Resistance to anidulafungin was 3.8% while no Candida isolate was resistant to amphotericin B. CONCLUSIONS: We report an overall increase in candidaemia but a minor decrease of C. albicans while C. glabrata and C. parapsilosis remain constant over this 10-year period.

Low level of antimicrobial resistance in Escherichia coli among Swedish nursing home residents.

BACKGROUND: Screening for bacterial colonization and antimicrobial resistance (AMR) among a defined population could aid in the identification of at-risk populations and provide targets for antibiotic stewardship and infection control programmes. METHODS: Two hundred and sixty-eight participants at 11 Swedish nursing homes underwent serial screening for colonization with Escherichia coli between March 2008 and September 2010. Seventy-two of the 268 participants (27%) were male. The median age was 85 y. Samples were collected from urine, the rectal mucosa, the groin, and active skin lesions. RESULTS: Two hundred and nine of 268 participants (78%) were colonized with E. coli at any body site/fluid. The specific colonization rates were 81% (rectum), 48% (urine), 30% (groin), 59% (unknown), and 13% (skin lesion). An antibiotic-resistant E. coli isolate was identified in 18% of all participants regardless of colonization status; all together, 87 resistant isolates were detected. Only 1 participant carried isolates with resistance to third-generation cephalosporins (cefotaxime and ceftazidime). CONCLUSIONS: The presence of resistance was generally low, and the greater part of the resistant cases was connected with 3 common antibiotics: ampicillin, trimethoprim/sulfamethoxazole, and ciprofloxacin. In spite of generally increasing resistance against third-generation cephalosporins in E. coli in Sweden, this study does not implicate residence at a Swedish nursing home as a risk factor for the acquisition of expressed cephalosporin resistance.

Clostridioides difficile outbreak detection: Evaluation by ribotyping and whole-genome sequencing of a surveillance algorithm based on ward-specific cutoffs.

OBJECTIVE: We evaluated the performance of an early-warning algorithm, based on ward-specific incidence cutoffs for detecting Clostridioides difficile transmission in hospitals. We also sought to determine the frequency of intrahospital Clostridioides difficile transmission in our setting. DESIGN: Diagnostic performance of the algorithm was tested with confirmed transmission events as the comparison criterion. Transmission events were identified by a combination of high-molecular-weight typing, ward history, ribotyping, and whole-genome sequencing (WGS). SETTING: The study was conducted in 2 major and 2 minor secondary-care hospitals with adjacent catchment areas in western Sweden, comprising a total population of ∼480,000 and ∼1,000 hospital beds. PATIENTS: All patients with a positive PCR test for Clostridioides difficile toxin B during 2020 and 2021. METHODS: We conducted culturing and high-molecular-weight typing of all positive clinical samples. Ward history was determined for each patient to find possible epidemiological links between patients with the same type. Transmission events were determined by PCR ribotyping followed by WGS. RESULTS: We identified 4 clusters comprising a total of 10 patients (1.5%) among 673 positive samples that were able to be cultured and then typed by high-molecular-weight typing. The early-warning algorithm performed no better than chance; patient diagnoses were made at wards other than those where the transmission events likely occurred. CONCLUSIONS: In surveillance of potential transmission, it is insufficient to consider only the ward where diagnosis is made, especially in settings with high strain diversity. Transmission within wards occurs sporadically in our setting.

Two outbreaks of cryptosporidiosis associated with cattle spring pasture events.

Over a period of less than four weeks, 50 human cases of cryptosporidiosis were reported from a relatively small geographical area in Sweden. All cases were associated with visits to cattle spring pasture events at two farms (referred to as Farm A and B). Epidemiological and microbiological evidence show that contact with calves at the farms was the most likely source of Cryptosporidium infections. Gp60 sequences from human and calf isolates at Farm A were identical to each other, but differed from those at Farm B where, again, human and calf gp60 sequences were identical, proving that the two outbreaks had no common origin. As a direct consequence of these two outbreaks, and guided by knowledge gained from the outbreak investigations, the Swedish Board of Agriculture and all relevant farmer advisory organizations have updated their hygiene instructions for farm visits.

A large-scale study of the random variability of a coding sequence: a study on the CFTR gene.

Coding single nucleotide substitutions (cSNSs) have been studied on hundreds of genes using small samples (n(g) approximately 100-150 genes). In the present investigation, a large random European population sample (average n(g) approximately 1500) was studied for a single gene, the CFTR (Cystic Fibrosis Transmembrane conductance Regulator). The nonsynonymous (NS) substitutions exhibited, in accordance with previous reports, a mean probability of being polymorphic (q > 0.005), much lower than that of the synonymous (S) substitutions, but they showed a similar rate of subpolymorphic (q < 0.005) variability. This indicates that, in autosomal genes that may have harmful recessive alleles (nonduplicated genes with important functions), genetic drift overwhelms selection in the subpolymorphic range of variability, making disadvantageous alleles behave as neutral. These results imply that the majority of the subpolymorphic nonsynonymous alleles of these genes are selectively negative or even pathogenic.