In this study, we evaluated demographical and clinical data, including baseline comorbidities and proposed risk factors for invasive candidiasis for all patients with Candida auris bloodstream infections. C. auris BSI was not gender specific, as we found similar numbers for both genders, with relatively high mean age. We noticed a significant and continuous annual increase in the number of cases of C. auris BSI, reaching its peak between June and August 2020. This could be explained by the advancement of identification technologies implemented at our mycology lab that increased the ability to identify C. auris and, most probably, the COVID-19 surge in Saudi Arabia during 202016.
Diabetes mellitus was the most frequently seen comorbidity in our cohort (76%), which is similar to what was reported by Chowdhary et al. 17. In contrast, Mohsin et al. showed a lower rate (39%) 12 .In that same study, 26% of patients had abdominal surgeries, higher than in our study in which (18.5%) had abdominal surgery; similarly, TPN was 17.4% in Oman compared to our cohort, 11.53% 12. Cancer was not common in our cohort, 30 (19.3%) patients, similar to what was reported in a previous study in Pakistan 18. End-stage renal disease was more common in our study 39.7% than in a study done in Northwestern India (6%) 19, but similar results in regard to other comorbidities, as they reported 21 out of 33 patients (64%) had hypertension and 5 (15%) with chronic liver disease 19. Among our patients, solid organ transplants and hematopoietic stem cell transplants were not common, and similar rates were also reported in different studies 2,12. Neutropenia was also uncommon, as only 8.33% of our patients had neutropenia; rates were also low as reported elsewhere, 4.34% and 1.6% 20 .
Similar to other studies, most patients had medical devices such as indwelling urinary catheters and/or CVCs that indicate biofilm formation's significant role as a virulence factor with C.auris 8,21,22. Medical device use was common in admitted patients with C. auris BSI as the majority of our patients (73%) had a urinary catheter placed, while it was up to 100% in other studies 8. Similarly, there were 134 patients (85.9%) placed on a central venous catheter, close to the reported 54 (73%) patients with central venous catheters in India 21. There were variabilities in the prevalence of invasive mechanical ventilation, where only half of the patients in a study in Brazil were on ventilators compared to 78% in our study and (64%) in another study19,23.
Antibiotics are almost universally prescribed prior to a C. auris BSI. A high rate of antibiotic use reported in our study (92.3%) is comparable to another study where 97% of patients received antibiotics before the onset of C. auris BSI 2 .We report a higher use of Corticosteroids as compared to another study, which collected data from three different continents (24%) 24. Isolates of C. auris from our study were mostly sensitive to caspofungin (94.6%), while resistance was the highest to fluconazole and voriconazole. A similar pattern was noted in most studies, where the MIC values for most isolates were elevated, above the resistant breakpoint, for both fluconazole and voriconazole, indicating resistance 25.
Data from a previous retrospective analysis of Candida spp BSI (other than C. auris) at our center and others showed some differences that would potentially help in more understanding of C. auris. Moreover, in terms of common clinical characteristics and comorbidities in patients with C. albicans versus non-albicans Candida species versus C. auris, we have noticed that rate of neutropenia, patients with malignancy in chemotherapy, and end-stage renal disease on hemodialysis were similar in C. albicans when compared to C. auris group in this cohort 26,27. In contrast, the C. auris group was almost identical to non-albicans Candida species group regarding corticosteroid use, rate of diabetes mellitus, and presence of CVC 27. Antibiotics use was similar in both candida auris 144(92.3%) and albicans 157(91%)28. While corticosteroid use was different between C. auris 125(80.12%) and C. albicans 56(32%) 28. Antifungal use was shown to be much less in C. albicans 8(12.5%) compared to candida auris 97(62.17%) 26. In comparing C. Albicans to other candida species, not including C. auris, Patients with BSI with C. albicans had a significantly lower rate in patients with cancer, chemotherapy, fluconazole, and itraconazole resistance compared to non-albicans Candida species. No significant resistance to fluconazole was also reported in patients with C. Albicans BSI 29–31.
Candida parapsilosis is another common candida species that shows a similar pattern to candida auris. Malignancy in candida parapsilosis patients was also uncommon 21(27%) 28. Antibiotic use was another similar factor between candida auris and candida parapsilosis 70(91%) 28. Neutropenia prevalence in some studies was higher in C. parapsilosis patients 9 (12%) patients, and Corticosteroid use was much less than in C. auris, accounting for 32% 28.
Although this study reveals valuable data that can be helpful in understanding this emerging pathogen, it involves a single-center experience. The study’s design is a limitation, as retrospective and descriptive reporting frequencies and percentages which doesn’t appropriately assess risk and causation. This would be mitigated by the inclusion of patients with BSI other than C. auris as a comparison to better assess prevalence ratios. In addition, some variables/data, such as the use of other medical devices and their details, were not included due to the difficulties in getting accurate data and the lower impact of these factors.