Mucocutaneous Candida Infections in Immunocompromised Patients

Candida species are considered opportunistic infections, and can cause a large variety of mucocutaneous and systemic diseases in immunocompromised individuals. In total, 95% of Candida infections in the USA are caused by C. albicans, C. glabrata, C. parapsilosis, C. tropicalis, and C. krusei, with proportions varying based on geographic region and patient population (Cleveland et al. in PLos One 10(3), 2015; Lockhart et al. in Clin Microbiol Newsl 36(17):131–136, 2014). Knowledge of these risk factors, and differences in disease processes, is extremely important when diagnosing and managing Candida infections. Differentiating species can be difficult; however, it is important to know their differences as various species are becoming increasingly resistant to antifungals (Lockhart et al. in J Clin Microbiol 50(11):3435–3442, 2012). In this review, we cover the epidemiology, specific disease entities, clinical manifestations, diagnostic methods, treatment modalities, and impact of each of the most common Candida species found in humans.

Mucocutaneous candida infections are among extremely common, and new studies are rapidly emerging regarding specific clinical presentations, diagnostic modalities, drug resistance, and treatment options. Approximately, 7% of Candida bloodstream infections are resistant to fluconazole, with over 70% of these species being Candida glabrata or Candida krusei (Lockhart in J Clin Microbiol 50(11):3435–3442, 2012; Lockhart et al. in Clin Infect Dis, 2017; Vallabhaneni et al. in Open Forum Infect Dis 2(4), 2015). Drug efflux pumps have been identified in C. parapsilosis allowing for increased resistance to fluconazole, ranging from 2–5% (Pristov and Ghannoum in Clin Microbiol Infect 25(7):792-798, 2019; Sadeghi et al. in J Mycol Med 28(1):51-58, 2018; Whaley et al. in Front Microbiol 7(JAN):2173, 2017). Additionally, recent studies highlight specific patient populations which may be prone to colonization by specific Candida species (Ghaddar et al. in Infect Dis Obstet Gynecol. 2019, 2019).

Mucocutaneous candida infections represent an ongoing battle among immunocompromised patients. There are numerous clinical presentations of which clinicians must be familiar, and various treatment modalities to consider. With newly resistant strains of Candida species, proper diagnosis and treatment is rapidly becoming more difficult, especially when the pathogen is a less common strain. C. albicans, C. glabrata, C. krusei, C. parapsilosis, and C. tropicalis represent the most common pathogenic strains found in humans, each with unique qualities, patient risk factors, and antifungal resistance patterns that require consideration when choosing treatment.