Prevalence and Genotypes of Nosocomial Clostridium difficile Infections in the Eastern Province of the Kingdom of Saudi Arabia: A Multi-Centre Prospective Study DC16-DC20
Dr. Nasreldin Elhadi,
Associate Professor, Department of Clinical Laboratory Science, College of Applied Medical Sciences, Imam Abdulrahman Bin Faisal University, Dammam, Kingdom of Saudi Arabia.
Introduction: Clostridium Difficile Infection (CDI) is a critical public health problem in hospitals due to unique characteristics and many countries have reported increased incidence and outbreak of severe cases of CDI.
Aim: To investigate the prevalence of C. difficile in the Eastern Province of the Kingdom of Saudi Arabia (KSA) in patients with inflammatory bowel disease relative to those with other diseases. The second objective was to understand the antimicrobial susceptibility patterns of clinical isolates of C. difficile against the antibiotics commonly used to treat CDI in hospitals and to identify the genotype and toxigenic profile of these isolates.
Materials and Methods: From October 2015 to May 2016, a total of 374 non-duplicated stool samples were collected from four hospitals in the Eastern Province of KSA and screened for the presence of C. difficile. Each sample was divided into two portions. One portion was cultured on C. Difficile Selective Agar (CDSA) and C. difficile CHROM agar and incubated in anaerobic conditions at 37°C for two days. The other portion was tested for Glutamate Dehydrogenase (GDH) activity. When this test was positive, authors tested the sample for toxins A and B using the VIDAS CDAB test.
Results: Authors found that 88 of the 374 samples (23.5%) were positive for C. difficile. The prevalence rate of toxigenic strains was 18.7% (70/374). The genotypes were distributed across five different ribotypes: 001 (63.6%), unknown (9.1%), historic 027 (3.4%), 017 (2.3%) and 015 (2.3%). In terms of toxigenic profile, 62 strains were (70.5%) tcdA+, tcdB+, Cdt-, 17 strains were tcdA-, tcdB-, Cdt- (19.3%), four strains were tcdA+, tcdB+, CdtA-, CdtB+ (4.5%), three strains were tcdA-, tcdB+, Cdt- (3.4%), one strain was tcdA+, tcdB-, CdtA+, CdtB+ (1.1%) and one strain was tcdA+, tcdB-, CdtA-, CdtB+ (1.1%). The in vitro antibiotic susceptibility of the 88 strains revealed that 94.3% were sensitive to all three tested antibiotics. Resistance to metronidazole and vancomycin was observed in 3.4% (n=3) of the samples and resistance to moxifloxacin in 2.3% (n=2).
Conclusion: The high prevalence of toxigenic strains in the present study indicates that CDI may be an underestimated problem in the Eastern Province of the KSA. Genotype 001 is the predominant strain present in this region. Vancomycin- and metronidazole-resistant strains were identified from this clinical setting.