Effective definition of low humoral response to Clostridioides difficile infection

Abstract

Background: Determination of the humoral response to Clostridioides difficile (CD) toxins could be of great value in the management of patients with CD infection (CDI).

Methods: A prospective study was conducted on the clinical characteristics and humoral response in patients with CDI. Determination of ELISA IgG CD anti-toxin B (tgcBiomics, Germany) was performed. The following dilutions were planned for each patient, 1:100, 1: 200, 1: 400, 1: 800: 1: 1600. A significant concentration of antibody was considered to be present in each dilution if an optical density 0.2 units higher than the negative control of the technique was evident.

Results: Eighty-five patients were included during the study period, November 2018-February 2020. The median age was 73 years (interquartile range: 62.5-85 years), with female predominance (45 patients, 52.9%). Thirty-nine patients (45.9%) had a severe infection. Seven patients (8.2%) had suffered an episode of CDI in the previous three months. Seventeen patients (20%) had one or more recurrent episodes during the three-month follow-up: No patient died during admission or required surgery for severe-complicated infection. The incidence of recurrence in patients with no antibody detected at 1:400 dilution was 25.4% (16 patients) while it was 4.3% (one patient) in patients with antibody present at that dilution (p = 0.03). Liver cirrhosis was associated with higher humoral response against CD.

Conclusions: Antibodies IgG CD anti-toxin B detection at a dilution of 1:400, using a B ELISA technique, effectively identified patients at increased risk of recurrence. This information could help assist in the management of patients.

Keywords: Clostridioides difficile; Enzyme-linked immunosorbent assay; Immunoglobulins; Liver cirrhosis; Recurrence.