This thesis is an investigation of the binary toxin of Clostridium difficile. The aim was to improve the understanding of the role of the binary toxin in pathogenesis. Quantitative real-time PCR (qPCR) was used to study expression of cdtA encoding the binary toxin enzymatic domain, cdtR encoding the binary toxin regulator and tcdB encoding toxin B, in response to growth phase and antimicrobial treatments in 2 C. difficile strains. Validation of a set of stable reference genes was required prior to qPCR analysis of gene expression. A universal set of genes could not be identified and reference genes should be validated on a strain-specific basis. Significant increases or decreases in expression were observed in response to levofloxacin and enrofloxacin exposure. The 2 strains selected were from different ribotypes and did not always share expression patterns. Binary toxin loci were sequenced in and compared between 10 C. difficile strains. A non-sense mutation in the cdtR gene of a ribotype 078 strain was identified and found to be restricted to toxinotype V isolates. This mutation is predicted to result in a truncated, non-functional protein. Despite the mutation, cdtA expression was still detected by qPCR. Finally, an evaluation of commercial nucleic acid extraction kits was performed. All kits produced RNA of adequate quality and yield, however, RNA isolated using the the Roche MagNA Pure LC RNA Isolation Kit could not be analyzed using the Agilent Bioanalyzer. It could not properly assign RNA integrity numbers due to a failure to remove small RNAs which were interpreted as degradation. All kits were suitable for DNA extraction with the exception of the MagNA Pure LC DNA Isolation Kit III which produced sheared DNA. In conclusion, this study demonstrated that the binary toxin regulator isn’t necessary for toxin expression and suggests other regulators of expression exist. Binary toxin gene expression did not necessarily correlate with expression of tcdB and expression levels vary between strains. This study also highlighted how the heterogeneity of C. difficile complicates gene expression experiments and the need for assessment of nucleic acid extraction methods due to critical variations between established commercial systems.

Clostridium difficile is an important hospital-acquired pathogen causing C. difficile-associated diarrhoea (CDAD) in patients exposed to antibiotics. The lack of information on bacteriophages of C. difficile, and the potential of phages as therapeutic agents for the treatment of CDAD, prompted the isolation and characterisation of phages active against clinical isolates of C. difficile in order to determine the prevalence and significance of phages of this anaerobe. Three (5.4 %) of 56 clinical C. difficile isolates induced by mitomycin C yielded dsDNA phages C2, C5, C6 and C8. The four phages differed from previously described C. difficile phages in particle morphology, burst size and host range. C2, C5 and C8 particles were members of the family Myoviridae, while C6 belonged to Siphoviridae. The burst sizes were 5 for C2, 7 for C5, 19 for C6 and 33 for C8. C8 had the broadest host range, lysing 27 out of 56 (48 %) C. difficile isolates, followed by C6 (43 %), C5 (20 %) and C2 (20 %). Superinfection experiments, restriction enzyme analysis and Southern hybridisation showed C2 and C5 to be closely related with C8 somewhat related to them, however, C6 was distantly related to the other three phages. C2 was further characterised as a representative phage. Its genome did not possess cohesive ends, and was shown to integrate chromosomally via an attP site identified within a 1.9 kb HindIII fragment. However, an integrase gene, which is typically close to the attP region, was not located. Nine of 16 HindIII fragments of C2, including the 1.9 kb fragment, were cloned into pUC18. Approximately 9 kb of the estimated 43 kb genome of C2 was sequenced and analysed. Seven of the nine translated sequences were homologous to phage structural proteins, two sequences were not homologous to any relevant protein in the Genbank and EMBL databases, and one was homologous to proteins of Clostridium species. Nucleotide homology between the C2 sequences and the recently sequenced C. difficile strain CD630 was found in three regions within CD630 genome. Seven of the nine sequences, including the 1.9 kb fragment, were clustered in one region. These data suggest that the genes constitute a phage structural gene module. The presence of C2-like sequences in CD630, and Southern hybridisation of C. difficile strains using phage probes, suggested related prophage sequences may be commonly present in this bacterial species. An investigation was carried out to determine the presence of toxin genes tcdA and tcdB, and PaLoc-associated gene tcdE, in phage DNA. In addition, the effect of phage infection on toxin production of toxigenic C. difficile strains was studied. Of the three genes, tcdE only was detected in phages C2, C5 and C8, but not in C6. Strains that maintained phages in a stable manner (lysogens) were isolated and used in toxin studies. The amount of toxin B produced was measured by cytotoxic assays using Vero cells, and toxin A production was measured by ELISA. Although phages did not encode toxin A or B genes, there was a significant increase in toxin B production in some lysogens. There was no increase in toxin A production. Transcriptional analyses of tcdA and tcdB in lysogens and parental strains was performed by real-time RT-PCR and Northern hybridisation to determine whether phage was affecting regulation of toxin transcription. Phage did not appear to affect toxin gene transcription, although results from real-time RT-PCR and Northern hybridisation were conflicting. A phage induced from the highly toxigenic reference strain VPI 10463 was also briefly characterised and investigated for its effect on toxin production in VPI 10463. The phage, ΦCV, had similar particle morphology to C2, C5 and C8, and had some HindIII bands in common with C2 and C5. Two cured variant strains produced significantly less toxin B compared to VPI 10463. In conclusion, several important properties of C. difficile phages were characterised. It appears these temperate phages may play a role in toxin production making them unsuitable as therapeutic agents for the treatment of CDAD. However, C2 phage may have potential as the basis for an integrative vector that will add to the genetic tools available for clostridia.

Thesis (Ph.D.)--University of Western Australia, 2004.

SANTOS, Ana Angélica Queiroz Assunção. Estudo das alterações morfológicas induzidas pela Toxina A, do Clostridium difficile em células epiteliais intestinais e do efeito protetor da Glutamina e Alanil-glutamina. 2011. 120 f. Dissertação (Mestrado em Ciências Médicas) - Universidade Federal do Ceará. Faculdade de Medicina, Fortaleza, 2010. / Submitted by denise santos (denise.santos@ufc.br) on 2013-12-06T13:02:50Z No. of bitstreams: 1 2011_dis_aaqasantos.pdf: 6513486 bytes, checksum: b4873c52295127b43af4843d288a42bf (MD5) / Approved for entry into archive by denise santos(denise.santos@ufc.br) on 2013-12-06T13:03:35Z (GMT) No. of bitstreams: 1 2011_dis_aaqasantos.pdf: 6513486 bytes, checksum: b4873c52295127b43af4843d288a42bf (MD5) / Made available in DSpace on 2013-12-06T13:03:35Z (GMT). No. of bitstreams: 1 2011_dis_aaqasantos.pdf: 6513486 bytes, checksum: b4873c52295127b43af4843d288a42bf (MD5) Previous issue date: 2011 / Clostridium difficile is the major cause of antibiotic-associated colitis, a disease with significant morbidity and mortality. Glutamine (Gln), a non-essential aminoacid, is a major fuel for the dynamic intestinal cell population. Alanyl-glutamine (Ala-Gln) is a dipeptide that is highly soluble and well tolerated. The aim of this study was to analyze the changes induced by Clostridium difficile toxin A (TcdA) in intestinal epithelial cell morphology and cytoskeletal element and the effect of Gln and Ala-Gln treatment, using advanced microscopic techniques. Twelve well cell culture plates, with 13 mm diameter glass coverlids, were seeded with 5x105 IEC-6 cells and grown for 24h in DMEM media. Afterwards, the wells were incubated for 24h as follow: control, TcdA (10 ng/mL), TcdA + Gln (10 mM) and TcdA + Ala-Gln (10 mM). The cells were than fixed in 4% formaldehyde for 14 h and afterwards they were examined by atomic force microscopy (AFM), scanning electronic microscopy (SEM) and Fluorescent microscopy. For the SEM the samples were fixed to samples holders with carbon adhesive tape and covered with a 15 mm gold film for conductivity by sputter. To fluorescent microscopy the cells were permeabilizided with PBS/Triton after that they were marked with stained with FITC-RhoA, Rodhamine-phallodin and DAPI performed using an inverted fluorescence microscope. An immunoblotting was realized with the same groups. The PVDF membrane was incubated with RhoA antibody overnight and afterwards activated by Amershan kit. The proteic control was made by α- tubulin. Also performed experiments of cellular proliferation and oxidative stress. As observed by AFM, SEM and Fluorescent microscopy TcdA caused intense cell shrinkage with multiple extensions. This change in shape was associated with collapse of the F-actin cytoskeleton demonstrated by fluorescent microscopy. An increase of RhoA production was detected in the groups treated with Gln e Ala-Gln. We demonstrated that TcdA dramatically altered the intestinal cell morphology and cytoskeleton organization and that Ala-Gln and Gln supplementation consistently prevented the intestinal epithelial cell damage induced by TcdA probably by increasing RhoA expression. The TcdA induced a reduction of 8.4% in cell proliferation while the Ala-Gln and Gln increased by 13.2% and 12.7%, respectively. The TcdA induced cells to oxidative damage, which was reversed by the use of Gln and Ala-Gln.. Our findings provide rationale for the potential use of Ala-Gln and Gln as adjuvant therapy in Clostridium difficile disease. Investigation of morphological and cytoskeleton changes using advanced microscopic techniques may aid in the evaluation of the protective or therapeutic activity of drugs against TcdA effects. / Clostridium difficile é a maior causa de colite associada ao uso de antibióticos, com significante morbidade e mortalidade. Glutamina (Gln), um aminoácido não-essencial, é a maior fonte combustível para a dinâmica das células intestinais. Alanil-glutamina (Ala-Gln) é um dipeptídeo, altamente solúvel e bem tolerado. O objetivo deste estudo foi analisar as alterações induzidas pela toxina A (TcdA) do Clostridium difficile na morfologia e elementos do citoesqueleto das células epiteliais intestinais e o efeito do tratamento com Gln e Ala-Gln, utilizando técnicas avançadas de microscopia. Placas de cultura de células com doze poços, previamente acrescidas de lamínulas de vidro, com diâmetro de 13mm, IEC-6, 5x105 foram semeadas e cultivadas por 24 horas em meio DMEM. Depois, as células foram incubadas por 24h de acordo com os seguintes grupos: Controle, TcdA (10 ng / mL), TcdA + Gln (10 mM) e TcdA + Ala-Gln (10 mM). As células foram fixados em formol a 4% por 14h, depois foram examinados na microscopia de força atômica (AFM), microscopia eletrônica de varredura (SEM), microscopia confocal e fluorescente. Para o SEM as amostras foram fixadas em porta amostras fita adesiva de carbono e cobertos com uma película de ouro 15 mm para adquirir condutividade por pulverização catódica. Para microscopia de fluorescência e o confocal, as células foram permeabilizadas com PBS/Triton depois foram marcados com RhoA- FITC, Faloidina –Rodamina e DAPI e as imagens capturadas através de um microscópio invertido de fluorescência ou confocal. Um immunoblotting foi realizado com os mesmos grupos. A membrana PVDF foi incubada com o anticorpo RhoA overnight, em seguida ativado pelo kit Amershan. O controle protéico foi feito por α-tubulina. Também realizarmos experimentos de proliferação celular e estresse oxidativo. Observou-se que a TcdA causa intenso encolhimento celular restando múltiplas extensões filamentosas. Esta alteração na forma foi associada ao colapso do citoesqueleto de F-actina demonstrada na microscopia de fluorescência. Um aumento da produção RhoA foi detectada no grupo tratado com Gln e Ala-Gln. Demonstramos que a morfologia das células intestinais e organização do citoesqueleto foram dramaticamente alteradas pela TcdA e que a suplementação com Ala-Gln e Gln impediu o dano celular epitelial intestinal induzida pela TcdA provavelmente por aumentar a expressão RhoA. A TcdA induziu uma redução de 8,4% na proliferação celular, enquanto o Ala-Gln e Gln aumentou 13,2% e 12,7%, respectivamente. A TcdA induziu as células ao dano oxidativo, que foi revertido com o uso de Gln e Ala-Gln. Nossos resultados fornecem justificativa para o uso potencial de Ala-Gln e Gln como terapia adjuvante na doença causada pelo Clostridium difficile. Investigação de alterações morfológicas e citoesqueleto usando avançadas técnicas de microscopia pode auxiliar na avaliação da atividade de proteção ou terapêutica de drogas contra os efeitos TcdA.

COSTA, Cecília Leite. Clostridium difficile : incidência da infecção e caracterização das cepas isoladas de pacientes com diarreia internados em um hospital oncológico de Fortaleza, Ceará. 2014. 80 f. Dissertação (Mestrado em Microbiologia Médica) - Universidade Federal do Ceará. Faculdade de Medicina, Fortaleza, 2014. / Submitted by denise santos (denise.santos@ufc.br) on 2014-12-15T11:58:42Z No. of bitstreams: 1 2014_dis_clcosta.pdf: 3047245 bytes, checksum: d675626e561cad2c2c02c02fa7253a65 (MD5) / Approved for entry into archive by denise santos(denise.santos@ufc.br) on 2014-12-15T11:59:51Z (GMT) No. of bitstreams: 1 2014_dis_clcosta.pdf: 3047245 bytes, checksum: d675626e561cad2c2c02c02fa7253a65 (MD5) / Made available in DSpace on 2014-12-15T11:59:51Z (GMT). No. of bitstreams: 1 2014_dis_clcosta.pdf: 3047245 bytes, checksum: d675626e561cad2c2c02c02fa7253a65 (MD5) Previous issue date: 2014 / Clostridium difficile is a strictly anaerobic, spore-forming, toxin-producing Gram positive bacillus. Currently, it is the main cause of nosocomial diarrhea associated with antibiotic use. Cancer patients are a major risk group for C. difficile infection (CDI), since the use of chemotherapeutic agents can alter the intestinal mucosa. Furthermore, these patients are often immunosuppressed and often use broad spectrum antibiotics. Considering the pathogenicity of C. difficile and the importance of this infection in hospitalized patients, this study aimed to determine the incidence and the phenotypical and genotypical characterization of strains of C. difficile isolated from cancer patients at Haroldo Juaçaba Hospital, Fortaleza, Ceará. During the 12 month period (May/2013 to May/2014) 41 diarrheic fecal samples were collected. Toxins A/B were detected from feces through a commercial ELISA detection kit. Then, the samples were cultivated on cefoxitine-cycloserine-frutose agar (CCFA) and incubated anaerobically. Isolates were submitted to several analyses, including phenotypical identification, detection of toxin genes and of a fragment of the tpi gene (definitive identification) by conventional PCR. The susceptibility of the strains to 12 antimicrobial agents was determined by E-test. Genotyping of the strains was also performed through molecular PFGE analysis. Out of 41 samples, 46.3% (19/41) were positive for either one or both of the performed tests: detection of toxin A/B and/or culture of C. difficile. C. difficile was recovered from three samples (15.8% - 3/19). The tpi, tcdA and tcdB genes were detected in all of the isolates. The binding domain of the binary toxin (cdtB) was not detected as well as no deletions were observed in the tcdC gene of the analysed isolates. All strains belonged to the same genotype, NAP4. Regarding the antimicrobial susceptibility of the strains, resistance to two or more antibiotics (azithromycin, tetracycline, ciprofloxacin, levofloxacin, ceftriaxone and cefotaxime) was observed. Out of the 19 positive patients, 57.9% (11/19) were using antibiotics and under chemotherapy. This paper describes the incidence of CDI in patients with cancer, and shows for the first time the detection of community-associated Clostridium difficile infection (CA-CDI) in those patients in Brazil, highlighting the importance of studying this bacterium for understanding the epidemiological situation of this infection and its spread among Brazilian hospitals. / Clostridium difficile é um bacilo Gram positivo, anaeróbio estrito, formador de esporos e produtor de toxinas. Atualmente, representa a principal causa de diarreia hospitalar associada ao uso de antibióticos. Pacientes oncológicos são um dos principais grupos de risco para infecção por C. difficile (CDI), visto que o uso de agentes quimioterápicos pode alterar a mucosa intestinal. Além disso, estes pacientes normalmente são imunodeprimidos e frequentemente utilizam antibióticos de largo espectro. Tendo em vista a patogenicidade do C. difficile e a importância da doença induzida por essa bactéria em ambiente hospitalar este estudo visou determinar a incidência e caracterização fenotípica e genotípica de cepas de C. difficile isoladas de pacientes oncológicos internados do Hospital Haroldo Juaçaba, Fortaleza, Ceará. Durante o período de 12 meses (maio/2013 a maio/2014) foram coletadas 41 amostras de fezes diarreicas. Toxinas A e/ou B foram detectadas a partir das fezes por meio de um kit de detecção comercial ELISA. Em seguida, as amostras foram cultivadas em Agar Cicloserina, Cefoxitina, Frutose (CCFA) e incubadas em anaerobiose. As cepas isoladas foram processadas e realizadas identificação fenotípica e análise de detecção dos genes das toxinas e do fragmento do gene tpi (identificação definitiva) por PCR convencional. A sensibilidade das cepas isoladas a 12 antimicrobianos foi determinada por meio de E-test. Também foi realizado a genotipagem das cepas por meio da análise molecular PFGE. 46,3% (19/41) das amostras foram positivas para presença das toxinas A/B por ELISA e/ou cultura do C. difficile. Dessas amostras, foram isolados C. difficile de três amostras (15,8% - 3/19). Em todos os isolados foram detectados os genes tpi, tcdA e tcdB. O domínio de ligação da toxina binária (cdtB) não foi detectado assim como também não foram observadas deleções no gene tcdC nos isolados. Todas as cepas apresentaram o mesmo genótipo, NAP4. Com relação à sensibilidade das cepas aos antimicrobianos foi verificado resistência a dois ou mais antimicrobianos (azitromicina, tetraciclina, ciprofloxacina, levofloxacina, ceftriaxona e cefotaxima). 57,9% (11/19) faziam uso de antibióticos e quimioterápicos. Este trabalho descreveu a incidência de CDI em pacientes oncológicos, e evidenciou pela primeira vez a presença de C.difficile em casos associados a comunidade (CA-CDI) nesses pacientes no Brasil, ressaltando a importância do estudo dessa bactéria para a compreensão da situação epidemiológica dessa infecção e de sua dispersão entre unidades hospitalares brasileiras.

FOSCHETTI, D. A. Toxinas A e B do Clostridium difficille induzem a expressão diferencial de receptor de Adenosina em células epiteliais intestinais: papel do receptor A2B. 2014. 160 f. Tese(Doutorado em Farmacologia) – Faculdade de Medicina, Universidade Federal do Ceará, Fortaleza, 2014. / Submitted by Erika Fernandes (erikaleitefernandes@gmail.com) on 2016-01-25T11:59:35Z No. of bitstreams: 1 2014_tese_dafoschetti.pdf: 5271291 bytes, checksum: 110e5955cf8edb636759d629ae0d7b60 (MD5) / Approved for entry into archive by Erika Fernandes(erikaleitefernandes@gmail.com) on 2016-01-25T11:59:46Z (GMT) No. of bitstreams: 1 2014_tese_dafoschetti.pdf: 5271291 bytes, checksum: 110e5955cf8edb636759d629ae0d7b60 (MD5) / Made available in DSpace on 2016-01-25T11:59:46Z (GMT). No. of bitstreams: 1 2014_tese_dafoschetti.pdf: 5271291 bytes, checksum: 110e5955cf8edb636759d629ae0d7b60 (MD5) Previous issue date: 2014-12-01 / Clostridium difficile is recognized to be a nosocomial pathogen that causes intense intestinal inflammation, epithelial barrier disruption and diarrhea. Adenosine production is increased under inflammatory situations. The adenosine receptor A2B is the most expressed receptor in the human and mice intestine. We investigated the effect of short- and long-term exposure to TcdA and TcdB in HCT-8 cells and isolated cecum epithelial cells. HCT-8 cells were exposed to TcdA or TcdB (10 ng/ml) for 2, 6 and 24h. We used a murine cecal loop model and murine infection model to evaluate the effects of TcdA and C. difficile infection, respectively. We demonstrated that HCT-8 and isolated intestinal cecum epithelial cells naturally express high levels of A2BR receptors. TcdA or TcdB alters the cell morphology, viability and proliferation pattern and caused gene expression increase of all AR subtypes in HCT-8. In isolated cecum epithelial cells, TcdA significantly (p<0.05) increased volume/length, weight/length, histopathology scores, neutrophil infiltration, as measured by MPO content, and induced an altered gene expression increase of all AR subtypes. PSB603 (10 nM) treatment significantly (p<0.05) reduced TcdA-induced tissue damage. Our findings support the hypothesis that Clostridium difficile toxins affect adenosine receptor expression and this action may be related to their severe inflammatory effect. We concluded that adenosine receptors may play a crucial role in regulating the inflammatory system in intestinal epithelium during C. difficile infection. / O Clostridium difficile é reconhecido por ser uma bactéria nosocomial, levando a intensa inflamação intestinal, quebra da barreira epitelial e diarreia. A produção de adenosina está aumenta durante eventos inflamatórios. O receptor de adenosina A2B (A2BR) é o mais expresso no intestino de humanos e camundongos. Nós investigamos o efeito de exposição às TcdA e TcdB, a curto e longo prazo, em células HCT-8 e células epiteliais intestinais isoladas do ceco. Células HCT-8 foram expostas a TcdA ou TcdB (10 ng/ml) por 2, 6 e 24h. Foi usado o modelo de alça cecal e de infecção pelo bacilo em murinos para avaliar os efeitos da TcdA e da infecção pelo C. difficile, respectivamente. Foi demonstrado que HCT-8 e células epiteliais intestinais isoladas do ceco naturalmente expressam altos níveis do receptor A2BR. TcdA e TcdB alteraram a morfologia celular, viabilidade e proliferação e causaram aumento da expressão gênica de todos os subtipos de receptores de adenosina e das citocinas IL-6 e IL-8 em HCT-8. Em células epiteliais intestinais isoladas do ceco, a TcdA significativamente causou um aumento do peso e volume/comprimento da alça cecal, escores histológicos e infiltrado neutrofílico, medido por MPO, e também causou alterações da expressão gênicas dos receptores de adenosina, tanto no modelo de alça cecal quanto na infecção pelo bacilo. O tratamento com PSB603, um antagonista do receptor A2BR, foi capaz de reverter os efeitos causados pelas toxinas do C. difficile. Nossos dados suportam a hipótese que as toxinas do C. difficile alteram a expressão dos receptores de adenosina e isso pode estar relacionado com os severos efeitos inflamatórios. Nós concluimos que os receptores de adenosina tenham um papel importante na regulação da inflamação em células epiteliais intestinais na infecção pelo C. difficile.

Clostridium difficile infection (CDI) is the most common hospital-associated infection and is linked to increased morbidity, mortality and costs. Asymptomatically colonized patients may act as an infection reservoir and their numbers have been found to exceed symptomatic CDI cases. In addition to higher rates of CDI among children hospitalized with cancer compared to those without an oncologic diagnosis, these patients also experience substantially higher C. difficile colonization rates. However, the current published literature does not adequately address the natural history of C. difficile colonization in this population, in terms of who is at greatest risk for developing colonization, duration of colonization, or progression to CDI. A retrospective longitudinal cohort study of pediatric oncology patients admitted to the oncology ward at McMaster Children’s Hospital (MCH) was conducted from September 1 2016 to February 28 2018. Patients who were routinely screened for antibiotic-resistant organisms (AROs) upon admission per hospital policies had their stored samples subsequently tested for asymptomatic carriage of C. difficile. A retrospective analysis was completed to determine predictors of colonization and risk factors for progression to subsequent CDI. We observed a lower colonization rate than other studies have reported in the literature. Duration of colonization was likely brief and none of the colonized patients subsequently developed CDI. There were no statistically significantly associated predictors for asymptomatic colonization when colonized patients were compared to those who were never colonized. / Thesis / Master of Science (MSc)

Source: Masters Abstracts International, Volume: 47-02, page: 0990. Adviser: Paul J. Rowan. Includes bibliographical references.

Bakgrund: Antibiotikabehandling kan medföra gastrointestinala besvär hos patienter. En vanlig orsak till detta är bakterien Clostridium difficile som normalt kan återfinnas i tarmfloran. Vid antibiotikabehandling kan flera av tarmflorans goda bakterier slås ut vilket kan resultera i att C. difficile växer till sig och genom toxiner ge gastrointestinala besvär. Detta kan orsaka patienter onödigt lidande och kostar hälso- och sjukvården mycket pengar årligen. Probiotika består av levande mikroorganismer och det finns teorier om att dessa kan ha en positiv inverkan på tarmfloran genom stabilisering av den samt förhindrar överväxt av C. difficile i floran.   Syfte: Syftet var att undersöka om behandling med probiotika kan förebygga C. difficile infektion och/eller lindra gastrointestinala besvär orsakade av C. difficile i samband med antibiotikabehandling.  Metod: Beskrivande litteraturöversikt. Litteratursökning gjordes i CINAHL och PubMed. Elva randomiserade kontrollerade studier utgjorde resultatet i litteraturöversikten efter att ha genomgått en kvalitetsgranskning. Resultat: En statistisk signifikant skillnad gällande förebyggande av C. difficile fanns i tre av de elva inkluderade studierna. Probiotika som symtomlindring mot C. difficile visade på en signifikant skillnad avseende diarré och lösa avföringar i fyra studier med signifikant fler fall i kontroll- än interventionsgrupperna. Andra symtom som undersöktes i sammanlagt sju studier var utspänd buk, buksmärta, illamående, kräkning och flatulens. Slutsats: Litteraturöversikten påvisade att probiotika i vissa fall kan ha effekt mot infektion orsakad av C. difficile i samband med antibiotikabehandling. Effekten visar sig i form av lindrande effekt på vissa gastrointestinala besvär. Litteraturöversikten kunde dock inte påvisa tillräcklig evidens på grund av varierande resultat i de inkluderade artiklarna. Det gör att probiotika i nuläget inte är aktuellt för implementering inom sjukvården i samband med antibiotikabehandling för att förebygga eller lindra infektion av C. difficile. / Background: Patients treated with antibiotics can experience gastrointestinal side effects. A common cause of the side effects is the bacterium Clostridium difficile. C. difficile can normally be found in the intestinal human flora. Antibiotic treatment can cause imbalance in the intestinal flora because antibiotics sometimes eliminate several of the good bacteria in the gastrointestinal microbiome. This can cause an overgrowth of C. difficile and through its toxins cause gastrointestinal side effects for the individual. The side effects of antibiotics and C. difficile can cause individual suffering and cost healthcare a lot of money annually. Probiotics contain living microorganisms and there are theories that these microorganisms can have a positive effect on the intestinal human flora by stabilizing the gastrointestinal microbiome and preventing overgrowth of C. difficile in the human flora.   Aim: The aim was to investigate if treatment with probiotics could prevent C. difficile infection and/or relieve the occurrence of gastrointestinal side effects caused by C. difficile in patients treated with antibiotics.    Method: A descriptive literature review. Data collection was made in CINAHL and PubMed. Eleven randomized controlled trials were included in this literature review after a quality review.   Results: A statistically significant difference in the prevention of C. difficile was found in three of the included articles. Probiotics used for relief of symptoms caused by C. difficile showed a significant difference in four studies that examined loose stools and diarrhea with more cases in the control group than the intervention group. Other symptoms examined in a total of seven articles were distended abdomen, abdominal pain, nausea, vomiting and flatulence.  Conclusion: This literature review proved that probiotics in some cases may have an effect on infections caused by C. difficile during treatment with antibiotics. The literature review could not prove sufficient evidence due to varying results in the included studies. That makes probiotics at the present time not relevant for implementation in healthcare services during treatment with antibiotics for prevention of C. difficile.

Clostridium difficile infection (CDI) is one of the most common healthcare-associated infections in the United States. Its incidence has been increasing in the recent years despite preventative measures. CDI increases annual expenses by 1.5 billion dollars. Cancer patients are at higher risk to acquire CDI, as explained by their frequent exposure to risk factors. CDI in cancer patients is associated with higher mortality rates and prolonged hospitalization. Furthermore, CDI affects the course of the disease by delaying treatments such as chemotherapy. Chemotherapeutics drugs are considered independent risk factors for CDI. This review discusses Clostridium difficile infection in cancer patients, including those who are receiving chemotherapy. Herein, we summarize recent data regarding the epidemiology, risk factors, including chemotherapy regimens, pathogenesis, diagnostic techniques and treatment options, including newer agents. Method: A literature search was performed using the PubMed and Google Scholar databases. The MeSH terms utilized in different combinations were 'clostridium difficile', 'neoplasia/cancer/oncology', 'chemotherapy', 'diagnosis', and 'treatment', in addition to looking up each treatment option individually to generate a comprehensive search. The articles were initially screened by title alone, followed by screening through abstracts. Full texts of pertinent articles (including letters to editors, case reports, case series, cohort studies, and clinical trials) were included in this review.