Is shorter also better in the treatment of Clostridioides difficile infection?

OBJECTIVES: To assess the effectiveness of shortened regimens of vancomycin or fidaxomicin in the treatment of Clostridioides difficile infection (CDI). METHODS: Adult patients with CDI hospitalized from January 2022 to May 2023 were included in this observational study. In patients with CDI treated with vancomycin or fidaxomicin, antibiotic treatment was discontinued after either 5 or 7 days of vancomycin or 5 days of fidaxomicin if there was a clinical response and improvement in laboratory parameters. The control cohort was treated with the standard 10 day regimen of either vancomycin or fidaxomicin. The follow-up was 60 days. Causative C. difficile strains were characterized by ribotyping and toxin gene detection when available. RESULTS: Twenty-five patients (median age 76 years) received shortened treatment with vancomycin (n = 21), or fidaxomicin (n = 4). Five cases fulfilled the criteria for severe CDI. Twenty-three patients completed follow-up; two died from causes other than CDI, and two developed recurrent CDI (8.0%). Ribotypes (RTs) 001 and 014 were the most prevalent with 20% each. In two C. difficile isolates, binary toxin genes were detected (RTs 078 and 023). In the control group of 22 patients recurrent CDI developed in 5 patients (22.7%). No statistically significant differences were found between the groups. CONCLUSIONS: Shortened treatment regimens for CDI with vancomycin and fidaxomicin were shown to be effective in our cohort of patients compared with 10 days of treatment. The recurrence rate was lower in the study group. A larger, prospective, double-blind, randomized, multicentre study is needed to support our findings.

To screen or not to screen medical students for carriage of multidrug-resistant pathogens?

BACKGROUND: The carriage of multidrug-resistant (MDR) pathogens in medical students has not been studied extensively, despite the fact that they are in contact with patients and exposed to a hospital environment. AIM: To investigate the intestinal and nasal carriage of MDR pathogens among medical students and its association with their lifestyle and demographic data. METHODS: In 2021, first- and final-year medical students were invited to the study. Two rectal swabs were used for detection of extended-spectrum ß-lactamase (ESBL)-producing, colistin-, tigecycline- or carbapenem-resistant Gram-negative bacteria and vancomycin-resistant enterococci. Nasal swab was used for Staphylococcus aureus culture. S. aureus isolates were characterized by spa typing; Gram-negative resistant isolates and meticillin-resistant S. aureus (MRSA) were subjected to whole-genome short and/or long sequencing. FINDINGS: From 178 students, 80 (44.9%) showed nasal carriage of S. aureus; two isolates were MRSA. In rectal swabs, seven ESBL-producing strains were detected. Sixteen students were colonized by colistin-resistant bacteria, three isolates carried the mcr-1 gene (1.7%). The mcr-9 (10.7%, 19/178) and mcr-10 (2.2%, 4/178) genes were detected by quantitative polymerase chain reaction, but only two colistin-susceptible mcr-10-positive isolates were cultured. The S. aureus nasal carriage was negatively associated with antibiotic and probiotic consumption. S. aureus and colistin-resistant bacteria were detected more frequently among students in contact with livestock. CONCLUSION: Medical students can be colonized by (multi)drug-resistant bacteria with no difference between first- and final-year students. The participation of students in self-screening increases their awareness of possible colonization by resistant strains and their potential transmission due to poor hand hygiene.

Updated Czech guidelines for the laboratory diagnosis of Clostridium difficile infections.

Clostridium difficile, a causative agent of intestinal infections (CDI) of varying severity, is an important nosocomial pathogen. Microbiological diagnosis, including an appropriate test algorithm and the corresponding interpretation of the results, is crucial for CDI confirmation. This update is based on the European guidance document for CDI laboratory diagnosis, taking into account the current CDI epidemiology and laboratory diagnostic approaches in the Czech Republic. Any diarrhoeal patient should be tested for CDI. The rectal swabs can only be used for testing in patients with paralytic ileus. Currently, a two-step test algorithm is recommended for CDI diagnosis. Due to a low positive predictive value, a single commercial test is not recommended as a stand-alone test for diagnosing CDI. Samples with a positive screening test (glutamate dehydrogenase or toxigenic strain nucleic acid) and a subsequent negative EIA (enzyme immunoassay) test for the presence of free toxins are diagnostically inconclusive. An option is to use a third confirmatory test; however, the current clinical status of the patient along with other laboratory findings should be considered in order to differentiate between ongoing CDI, carriage of a toxigenic strain of C. difficile, and other causes of diarrhoea. In general, when implementing a new diagnostic test, its sensitivity and specificity should be compared against the reference method. Diagnostic tests should refer to the data from published comparative studies and should not rely solely on information provided by the manufacturer. Currently, there is no commercial test available for detection of free C. difficile toxins in stool samples with 100 % sensitivity. Moreover, the pre-analytical conditions (storage and transport temperature of stool samples) and/or the initiation of an empirical therapy prior to the sampling may decrease the sensitivity of the assay.

How to: Surveillance of Clostridium difficile infections.

BACKGROUND: The increasing incidence of Clostridium difficile infections (CDI) in healthcare settings in Europe since 2003 has affected both patients and healthcare systems. The implementation of effective CDI surveillance is key to enable monitoring of the occurrence and spread of C. difficile in healthcare and the timely detection of outbreaks. AIMS: The aim of this review is to provide a summary of key components of effective CDI surveillance and to provide some practical recommendations. We also summarize the recent and current national CDI surveillance activities, to illustrate strengths and weaknesses of CDI surveillance in Europe. SOURCES: For the definition of key components of CDI surveillance, we consulted the current European Society of Clinical Microbiology and Infectious Diseases (ESCMID) CDI-related guidance documents and the European Centre for Disease Prevention and Control (ECDC) protocol for CDI surveillance in acute care hospitals. To summarize the recent and current national CDI surveillance activities, we discussed international multicentre CDI surveillance studies performed in 2005-13. In 2017, we also performed a new survey of existing CDI surveillance systems in 33 European countries. CONTENT: Key components for CDI surveillance are appropriate case definitions of CDI, standardized CDI diagnostics, agreement on CDI case origin definition, and the presentation of CDI rates with well-defined numerators and denominators. Incorporation of microbiological data is required to provide information on prevailing PCR ribotypes and antimicrobial susceptibility to first-line CDI treatment drugs. In 2017, 20 European countries had a national CDI surveillance system and 21 countries participated in ECDC-coordinated CDI surveillance. Since 2014, the number of centres with capacity for C. difficile typing has increased to 35 reference or central laboratories in 26 European countries. IMPLICATIONS: Incidence rates of CDI, obtained from a standardized CDI surveillance system, can be used as an important quality indicator of healthcare at hospital as well as country level.

Increasing incidence of Clostridium difficile ribotype 001 associated with severe course of the infection and previous fluoroquinolone use in the Czech Republic, 2015.

The aim of the study was to provide an update on the epidemiology of C. difficile infection (CDI) in a representative number of hospitals within the Czech Republic in 2015. In 2015, twenty-eight Czech hospitals were invited to participate in a CDI study. Laboratories sent the first 20 consecutive C. difficile isolates for characterization by capillary-electrophoresis (CE) ribotyping and the presence of toxin genes and collected patient data on previous hospitalization, antibiotic treatment, the number of CDI episodes and the course of CDI. The mean incidence of CDI was 5.2 [95% CI 4.2-6.2] cases per 10,000 patient-bed days in 27 hospitals in 2015. Of 490 C. difficile isolates, the prevalent PCR ribotypes (RTs) were 001 (n = 164, 33.5%) and 176 (n = 125, 25.5%) followed by 014 (n = 37, 7.6%), 012 (n = 17, 3.5%), 020 (n = 16, 3.3%), 017 (n = 14, 2.9%) and 002 (n = 11, 2.2%). A severe course of CDI was reported in 104 cases (21.2%) with significant association with RT001 infection (p = 0.03). CDI recurrence was 10.8% (n = 53). The previous use of fluoroquinolones was associated with RTs 001 and 176 CDIs (p = 0.046 and p = 0.041). We observed a persistence of RTs 001 and 176 CDIs in the Czech Republic that was associated with the previous use of fluoroquinolones. This highlights the need for a reduction in fluoroquinolone use in Czech hospital settings.

[Clostridium difficile remains a medical challenge]. / Clostridium difficile stále aktuální.

Intestinal infections caused by the Clostridium difficile (CDI) bacterium currently represent a serious medical problem. They belong to the most frequent nosocomial infections and, in some countries, a community-acquired disease with a significantly increased incidence of community associated CDI is reported. The infection can manifest as mind diarrhea, but also as a life-threatening illness accompanied by paralytic ileus and painful distension of the colon, developing into secondary sepsis. Recurrent forms difficult to manage are a relatively common complication of the disease. Severity of infection may be influenced by the virulence of the causative strain. Severe course of the disease is associated with ribotypes 027, 078, 001. In the Czech Republic, ribotypes 001 and 176 have predominated over the last years. Laboratory diagnosis is based on the detection of C. difficile glutamate dehydrogenase and free clostridium toxins (A,B) in a diarrheal stool sample or culture of C. difficile in anaerobic conditions. Metronidazole, vancomycin and fidaxomicin are the drugs of choice in the treatment of aC. difficile with administration according to the actual treatment guidelines. Fecal bacteriotherapy is recommended in treatment and prevention of recurrent CDI. Surgery is indicated in progressive complicated forms when no response to medication is achieved and the patient is in a critical condition.Key words: Clostridium difficile intestinal infection epidemic ribotypes clostridium colitis treatment.

Molecular characterisation of Czech Clostridium difficile isolates collected in 2013-2015.

Clostridium difficile is a leading nosocomial pathogen and molecular typing is a crucial part of monitoring its occurrence and spread. Over a three-year period (2013-2015), clinical C. difficile isolates from 32 Czech hospitals were collected for molecular characterisation. Of 2201 C. difficile isolates, 177 (8%) were non-toxigenic, 2024 (92%) were toxigenic (tcdA and tcdB) and of these, 677 (33.5%) carried genes for binary toxin production (cdtA, cdtB). Capillary-electrophoresis (CE) ribotyping of the 2201 isolates yielded 166 different CE-ribotyping profiles, of which 53 were represented by at least two isolates for each profile. Of these, 29 CE-ribotyping patterns were common to the Leeds-Leiden C. difficile reference strain library and the WEBRIBO database (83.7% isolates), and 24 patterns were recognized only by the WEBRIBO database (11.2% isolates). Isolates belonging to these 53 CE-ribotyping profiles comprised 94.9% of all isolates. The ten most frequent CE-ribotyping profiles were 176 (n=588, 26.7%), 001 (n=456, 20.7%), 014 (n=176, 8%), 012 (n=127, 5.8%), 017 (n=85, 3.9%), 020 (n=68, 3.1%), 596 (n=55, 2.5%), 002-like (n=45, 2.1%), 010 (n=35, 1.6%) and 078 (n=34, 1.6%). Multi-locus sequence typing (MLST) of seven housekeeping genes performed in one isolate of each of 53 different CE-ribotyping profiles revealed 40 different sequence types (STs). We conclude that molecular characterisation of Czech C. difficile isolates revealed a high diversity of CE-ribotyping profiles; the prevailing RTs were 001 (20.7%) and 176 (027-like, 26.7%).

[Diagnosis of infections caused by Clostridium difficile in the Czech Republic: availability, possibilities, and interpretation of laboratory results]. / Diagnostika infekcí vyvolaných Clostridium difficile v Ceské republice--dostupnost, moznosti, interpretace laboratorních nálezu.

OBJECTIVE: To assess the availability of the laboratory diagnosis of infections caused by C. difficile in the Czech Republic (CR), including the range of tests used, possible combinations, and adequate interpretation of model results. MATERIAL AND METHODS: Data were collected through a web questionnaire survey with the participation of representatives of 61 public and private microbiological laboratories. The questionnaire addressed the use of diagnostic test kits and culture media in the diagnosis of C. difficile infection (CDI). In addition, the respondents were asked to interpret a glutamate dehydrogenase (GDH) positive and, at the same time, toxin A/B negative result, without or with laboratory confirmation if available. RESULTS: In the CR, the most commonly used test in the diagnosis of CDI is the C. DIFF Quik Chek Complete® test (Alere) for the detection of GDH and A/B toxins, as reported by 50 (82%) laboratories. Anaerobic culture is performed by 43 (70.5%) laboratories, 21 (48.8%) of which use selective agar (Oxoid). Direct detection of DNA of toxigenic C. difficile is feasible in 17 (27.9%) laboratories, with most of them (15 laboratories) using the closed system Xpert® C. difficile (Cepheid). The diagnosis based only on the detection of GDH and A/B toxins is used by 13 (21.3%) laboratories. Two (3.3%) laboratories detect A/B toxins alone and three (4.9%) laboratories carry out the detection of A/B toxins followed by anaerobic culture. A three step scheme: detection of GDH and A/B toxins with subsequent anaerobic culture is used by 26 (42.6%) laboratories. The detection of GDH and A/B toxins along with a PCR assay are provided by three (4.9%) laboratories. A complete diagnostic scheme for CDI (detection of GDH and A/B toxins, direct detection of DNA, and aerobic culture) is feasible in 14 (23%) laboratories. CONCLUSION: This questionnaire survey study identified 24 different testing algorithms to be in use within the study period (April to July 2014) in the CR. Five (8.2%) laboratories have no highly sensitive screening test such as the detection of GDH or nucleic acid amplification test (NAAT) included in their testing algorithm. Thirteen (21.3%) laboratories perform the detection of GDH and A/B toxins but have no confirmation method to be used if only one test turns out positive. In the case of GDH positivity and A/B toxin negativity, the result should be provided with a supplementary comment on further possibilities for the laboratory detection of CDI and the claimed sensitivity of the test used. If no confirmation test is available, the result should be considered as epidemiologically and clinically significant, once other possible causes of diarrhoea are ruled out.

The emergence of Clostridium difficile PCR-ribotype 001 in Slovakia.

PURPOSE: The purpose of this study was to determine the incidence of Clostridium difficile infections (CDI) and to characterise the isolates in 14 departments of ten academic hospitals in Slovakia. METHODS: During a one-month study (September 2012) all unformed stool samples were investigated using a rapid test to detect the presence of GDH and toxins A/B. Positive samples were cultured anaerobically and C. difficile isolates were characterised by ribotyping, multiple-locus variable-number tandem repeats analysis, and gyrA, rpoB and ermB investigation. RESULTS: A total of 194 unformed stool samples were investigated and 38 (19.6 %) had a positive rapid test. Of 38 samples, 27 revealed a positive result for GDH and free toxins A/B in the stool, and 11 samples only for the presence of GDH. The mean CDI incidence in 2012 was 5.2 cases per 10,000 patient bed-days. Twenty C. difficile isolates were available for molecular analysis; seventeen belonged to PCR-ribotype 001 (85 %) whereas the remaining three isolates were identified as PCR-ribotypes 017, 078 and 449. MLVA of the PCR-ribotype 001 isolates identified two clonal complexes and a close genetic relatedness between isolates from six different hospitals. Molecular analysis of antibiotic-resistance determinants revealed the presence of ermB gene encoding resistance to the MLSB group of antibiotics in 90 % of isolates, and Thr82Ile amino acid substitution in the gyrA gene associated with resistance to fluoroquinolones in 85 % of isolates. CONCLUSIONS: We conclude that C. difficile PCR-ribotype 001 is the predominant PCR-ribotype in Slovakia with a strong potential for clonal spread and development of multidrug resistance.

Mutations in HINT1 are one of the most frequent causes of hereditary neuropathy among Czech patients and neuromyotonia is rather an underdiagnosed symptom.

Mutations in the HINT1 gene were recently discovered as being the major cause of autosomal recessive axonal neuropathy with neuromyotonia. This combination was clinically recognized and described previously in a few reports but is generally unknown. We aimed to establish the importance of HINT1 mutations as the cause of hereditary neuropathy and particularly hereditary motor neuropathy/axonal Charcot-Marie-Tooth (HMN/CMT2) among Czech patients. Overall, mutations in the HINT1 gene seem to be a surprisingly frequent cause of inherited neuropathy in our group of patients. Biallelic pathogenic mutations were found in 21 patients from 19 families. The prevalent mutation in the Czech population is the p.R37P (95% of pathogenic alleles). Clinically, all patients with biallelic mutations presented with early onset of symptoms at the end of the first decade. Foot/toe extension weakness to plegia was present in almost all patients. Neuromyotonia was present in all but two patients. However, it had been properly recognized in only three patients prior to molecular genetic diagnosis. HINT1 mutations seem to be one of the most frequent causes of inherited neuropathy and are probably the most frequent cause of HMN in Czech patients. We suggest all HMN/CMT2 patients be tested for the presence of the prevalent mutation, the p.R37P.

[Diagnosis of Clostridium difficile infections: comparative study of two immuno enzyme assays with confirmation by PCR and culture followed by PCR ribotyping]. / Diagnostika Clostridium difficile infekcí - porovnávací studie dvou imunoenzymatických metod s konfirmací pomocí PCR a kultivace s následnou ribotypizací kmene*

STUDY OBJECTIVE: Comparison of two commercially avail-able tests for the detection of Clostridium difficile Glutamate Dehydrogenase (GDH) and toxins A and B for their sensitivity and specificity. MATERIAL AND METHODS: Eighty-six stool samples from patients hospitalised in the Motol University Hospital were analysed. GDH and toxins A and B were assayed in parallel by two tests: C. difficile Quik Chek Complete® (Techlab, USA) and Liaison® C. difficile GDH and Toxins AαB (DiaSorin, USA). From the stool samples, nucleic acids were also isolated using the UltraClean® Fecal DNA kit (MoBio Laboratories, USA). The commercially available C. difficile Elite MGB® kit (Nanogen, Italy) was used for the polymerase chain reaction (PCR). Anaerobic culture on C. difficile selective medium (Oxoid) was performed for all positive samples at least in one test. Pure isolates were characterized by PCR ribotyping. RESULTS: Thirty-six (42%) samples were GDH negative and toxin A/B negative by both tests. Twenty (23%) samples were GDH positive and toxin A/B positive by both tests. Nine (10%) samples were GDH positive and toxin negative by both tests, but were positive by PCR. Eleven (13%) samples that were GDH positive and toxin negative by both tests remained negative by PCR. Six (7%) samples only were GDH positive and toxin positive by the Liaison® test alone. Four (5%) samples were GDH-positive by theLiaison® test alone. Culture failure was observed in 11 (13%) samples, of which seven were positive by PCR. PCR was inhibited in five (6%) samples. The following toxigenic ribotypes: AI-3, 001, 002, 012,014, 017, 020, 049, 054, 078, 176, 203, and 413 and non-toxigenic ribotypes: AI-34, AI-61, 010, 485, 495, and 596 were identified. CONCLUSION: The Liaison® test had seven percent higher sensitivity for the detection of toxins A/B. The two-step protocol of the tests is also cost-saving. The savings can be used e.g. for incorporating the PCR techniques into the diagnostic algorithm of the laboratory.

DFNB49 is an important cause of non-syndromic deafness in Czech Roma patients but not in the general Czech population.

Due to endogamy, the Roma have a higher risk for autosomal recessive (AR) disorders. We used homozygosity mapping on single-nucleotide polymorphism chips in one Czech Roma consanguineous family with non-syndromic hearing loss (NSHL). The second largest homozygous region in a deaf patient was mapped to the previously reported DFNB49 region. The MARVELD2 gene was recently reported as a causal gene for NSHL DFNB49. Sequencing of the MARVELD2 gene revealed a previously reported homozygous mutation c.1331+2 T>C (IVS4 + 2 T>C) in the deaf child. Subsequently, the same mutation was found in two more Roma families from an additional 19 unrelated Czech Roma patients with deafness tested for the MARVELD2 gene. To explore the importance of MARVELD2 mutations and DFNB49 for the general Czech and Central European population with early hearing loss we also tested 40 unrelated Czech patients with AR NSHL. No pathogenic mutation in the MARVELD2 gene was found in a group of 40 Czech non-Roma patients. Mutations in the MARVELD2 gene seem to be a significant cause of early NSHL in Czech Roma and this gene should be tested in this group of patients after GJB2.