University thesis:
Dissertation, Georg-August-Universität Göttingen, 2022
Footnote:
Description:
Clostridioides difficile (C. difficile) is a Gram-positive, spore forming rod shaped bacterium. It is responsible for most cases of nosocomial diarrhoea in Northern America and Europe. Especially antibiotic treatment is a risk factor for a manifestation of C. difficile-associated disease. The symptoms are mainly caused by toxins, which affect the intestinal epithelial layer in the large intestine. The expression of toxins differs between different strains/ribotypes of the pathogen. Besides a symptomatic infection, C. difficile can cause an asymptomatic colonization of the intestine. This as...
Clostridioides difficile (C. difficile) is a Gram-positive, spore forming rod shaped bacterium. It is responsible for most cases of nosocomial diarrhoea in Northern America and Europe. Especially antibiotic treatment is a risk factor for a manifestation of C. difficile-associated disease. The symptoms are mainly caused by toxins, which affect the intestinal epithelial layer in the large intestine. The expression of toxins differs between different strains/ribotypes of the pathogen. Besides a symptomatic infection, C. difficile can cause an asymptomatic colonization of the intestine. This asymptomatic colonization occurs more frequently in young children than in adults. There is no profound explanation for this circumstance yet. To find potential differences in the characteristics of C. difficile strains in infants and adults 137 C. difficile isolates from 48 children in their first year of life were subject to antimicrobial resistance testing, PCR-based screening for toxin genes and mass-spectrometry-based identification of the ribotype 027. The latter is suspected to cause severe courses of infection. The findings were compared to existing data from adults. Antimicrobial resistance was tested using an epsilomer test and detected for metronidazole in one, for erythromycin in 16 and for moxifloxacin in two of the strains, whereas no resistance was observed for vancomycin or rifampicin. Newly observed resistances against erythromycin in children with detection of previously completely sensitive isolates was reported for C. difficile isolates from two out of 48 children. In 20 children non-toxigenic strains were detected, from 27 children toxigenic strains were isolated, while both toxigenic and non-toxigenic strains were isolated from one child. Ribotype 027 was not observed. These results mainly match with characteristics found in previous studies among infants and adults. Differences were found concerning the prevalence of antibiotic resistances, which are described to be more frequent in other parts of the world than in the tested infants. Differences were as well found concerning the prevalence of ribotype 027, which was not observed in the isolates of our infants but could be detected in former studies among asymptomatic adults. The latter fact can be discussed as a potential cause for the diverging impact of C. difficile on infants and adults. Beyond that, existing theories comprising the impact of the alteration of the composition of the gut microbiome and of the functionality of the immune system during lifetime should be pursued.$v2022-04-06$v2022-04-06$xN$4LF