502. Enhanced Sporulation and Vancomycin Resistance Associated with Clostridium difficile from Recurrent Infections.
Session: Poster Abstract Session: Healthcare Epidemiology: Updates in C. difficile
Thursday, October 4, 2018
Room: S Poster Hall
Posters
  • Poster 502 IDWEEK LETR.pdf (730.0 kB)
  • Background: Recurrent Clostridium difficile infection (R-CDI) remains a significant healthcare problem. Our aim was to analyze sporulation and antimicrobial resistance of C. difficile in biofilms as a potential reservoir for recurrence.

    Methods: C. difficile isolates obtained from patients with initial CDI (I-CDI) (n=93) and from patients with R-CDI (n=39) were analyzed. Isolates were identified by PCR and MALDI-TOF MS and ribotyped using 16S-RNA amplification and capillary electrophoresis.

    Biofilm production was assessed by the crystal violet microtiter-plate method. Susceptibilities to vancomycin and linezolid were determined both in planktonic and in biofilm cells and total viable cells and spore were quantified in biofilm cells.

    Results: All I-CDI and R-CDI isolates were biofilm producers and >75% were ribotype 027.

    MICs for vancomycin and linezolid were higher in biofilm than in planktonic cells in both I-CDI and R-CDI isolates (p<0.05) (Table 1). Isolates recovered from R-CDI showed a higher vancomycin resistance (MIC >2 mg/L) and sporulated 2-log10 higher than isolates from I-CDI (p<0.01 and p=0.086 respectively).

    Table 1. – Antimicriobial susceptibilities of C. difficile from I-CDI and R-CDI patients.

     

    Group

     

    Vancomycin

    Linezolid

    Phase

     Range

    (mg/L)

    GM

    (mg/L)

    % R

    Range

    (mg/L)

    GM

    (mg/L)

    % R

    I-CDI

    Planktonic

    0.25-4

    1.68*

    9.2 (6/69)*

    0.03-32

    3.38*

    34.8 (24/69)

     

    Biofilm

    8 >128

    73.9*

    100 (73/73)

    4 >128

    60.85*

    98.5 (66/67)

    R-CDI

    Planktonic

    2-4

    1.69*

    27.3 (9/33)*

    0.25-128

    3.31*

    35.1 (14/37)

     

    Biofilm

    4 >128

    72.6*

    100 (34/34)

    8 >128

    59.5*

    93.5 (29/31)

    *Significant difference p<0.05; GM: Geometric mean; %R: Resistant

     

     

    Conclusion: C. difficile isolates in biofilms were 100-fold more resistant to vancomycin than planktonic cells. Isolates recovered from patients with R-CDI showed higher sporulation capacities than C. difficile recovered from I-CDI patients.

    Our data suggest that biofilm formation ability may play a key role in R-CDI by contributing to vancomycin resistance/tolerance. Furthermore,  C. difficile from recurrent episodes sporulated to a greater capacity which may facilitate prolonged C. difficile persistence in the gut following therapy for R-CDI.

    Laura E. Tijerina-Rodriguez, MSc1, Adrián Martínez-Meléndez, MSc1, Licet Villarreal-Treviño, PhD1, Rayo Morfín-Otero, MD, PhD2, Adrian Camacho-Ortiz, MD, PhD3, Simon D. Baines, PhD4, Eduardo Rodríguez-Noriega, MD, PhD5 and Elvira Garza-González, PhD6, (1)Facultad de Ciencias Biológicas, Universidad Autónoma de Nuevo León, Monterrey, Mexico, (2)Hospital Civil de Guadalajara, "Fray Antonio Alcalde", Guadalajara, Mexico, (3)Infectious Diseases, Hospital Universitario "Dr. José Eleuterio González". Universidad Autónoma de Nuevo León, Monterrey, Mexico, (4)University of Hertfordshire, Hertfordshire, United Kingdom, (5)Instituto de Patología Infecciosa “Dr. Francisco Ruiz Sánchez”. CUCS. UDG, Guadalajara, Mexico, (6)Hospital Universitario "Dr. José Eleuterio González". Universidad Autónoma de Nuevo León, Monterrey, Mexico

    Disclosures:

    L. E. Tijerina-Rodriguez, None

    A. Martínez-Meléndez, None

    L. Villarreal-Treviño, None

    R. Morfín-Otero, None

    A. Camacho-Ortiz, None

    S. D. Baines, None

    E. Rodríguez-Noriega, None

    E. Garza-González, None

    Findings in the abstracts are embargoed until 12:01 a.m. PDT, Wednesday Oct. 3rd with the exception of research findings presented at the IDWeek press conferences.