Asymptomatic and yet C. difficile-toxin positive? Prevalence and risk factors of carriers of toxigenic Clostridium difficile among geriatric in-patients

Abstract

Background Clostridium difficile infections (CDI) are the most frequent cause of diarrhoea in hospitals. Geriatric patients are more often affected by the condition, by a relapse and complications. Therefore, a crucial question is how often colonization with toxigenic Clostridium difficile strains occurs in elderly patients without diarrhoea and whether there is a “risk pattern” of colonized patients that can be defined by geriatric assessment. Furthermore, the probability for those asymptomatic carriers to develop a symptomatic infection over time has not been sufficiently explored.MethodsWe performed a cohort study design to assess the association of clinical variables with Clostridium difficile colonization. The first stool sample of 262 consecutive asymptomatic patients admitted to a geriatric unit was tested for toxigenic Clostridium difficile using PCR (GeneXpert, Cepheid). A comprehensive geriatric assessment (CGA) including Barthel Index, Mini Mental State Examination (MMSE) and hand grip-strength was performed. In addition, Charlson Comorbidity Index, body mass index, number and length of previous hospital stays, previous treatment with antibiotics, institutionalization, primary diagnoses and medication were recorded and evaluated as possible risk factors of colonization by means of binary logistic regression. Secondly, we explored the association of C. difficile colonization with subsequent development of CDI during hospital stay.ResultsAt admission, 43 (16.4%) patients tested positive for toxin B by PCR. Seven (16.3%) of these colonized patients developed clinical CDI during hospital stay, compared to one out of 219 patients with negative or invalid PCR testing (Odds ratio 12,3; Fisher’s exact test: p = 0.000). Overall, 7 out of 8 (87.5%) CDI patients had been colonized at admission. Risk factors of colonization with C. difficile were a history of CDI, previous antibiotic treatment and hospital stays. The parameters of the CGA were not significantly associated with colonization.ConclusionColonization with toxigenic Clostridium difficile strains occurs frequently in asymptomatic patients admitted to a geriatric unit. Previous CDI, antibiotic exposure and hospital stay, but not clinical variables such as CGA, are the main factors associated with asymptomatic Clostridium difficile carriage. Colonization is a crucial risk factor for subsequent development of symptomatic CDI.

Pediatric oncology and stem cell transplant patients with healthcare‐associated Clostridium difficile infection were already colonized on admission

“…The asymptomatic colonization rate of toxigenic C. difficile in hospitalized adult patients was found to range from 3% to 20%, but this is higher (24%–55%) in infants and young children …”

“…8 Furthermore, typing studies have found that only a small proportion of CDI is linked to nosocomial transmission. [9][10][11] The asymptomatic colonization rate of toxigenic C. difficile in hospitalized adult patients was found to range from 3% to 20%, [12][13][14][15] but this is higher (24%-55%) in infants and young children. 16,17 Children and adolescents undergoing therapy for cancer are at high risk for CDI due to exposure to several known CDI risk factors including profound myelosuppression and broad-spectrum antibiotics.…”

Les vaccins dans la prévention des infections associées aux soins

“…De plus, les patients à risque d'IAS sont souvent âgés et immunodéprimés, il peut ainsi s'avérer difficile d'atteindre une réponse immune protectrice. Par ailleurs, les agents infectieux responsables d'IAS sont souvent d'origine endogène, provenant de la flore commensale et/ou associés à un portage mais peuvent également avoir une origine exogène, résultant de la transmission croisée en milieu de soins [14][15][16][17][18]. L'utilisation de vaccins pour prévenir les IAS devrait ainsi être envisagée chez les patients pour les protéger d'agents infectieux dont ils sont porteurs.…”

“…Il s'agit d'une IAS par essence. C. difficile est principalement d'origine endogène [16], cependant, la transmission croisée manuportée via les soignants est possible [59]. Aux États-Unis, c'est la première cause d'IAS [3].…”

“…La colonisation est une étape essentielle dans l'infection à C. difficile, l'excrétion de spores dans l'environnement contribue à un réservoir de la bactérie dans les structures de soins [16,63]. En conséquence, un vaccin qui préviendrait ou réduirait le portage est très attendu.…”