Basic blood chemistry biomarkers are not specific for diagnosing Candida infection. However, more specific antibody, antigen, and metabolite testing, along with a comprehensive history and symptom evaluation can help identify overgrowth.
Although fungal infection may present with elevated white blood cells and neutrophilia (Brown 2012), as well as elevated eosinophils (Figueiredo 2018), common blood chemistry panels aren’t used to identify infection. However, more specific biomarkers can be used along with a thorough history and symptom evaluation.
The most common blood testing for Candida albicans exposure is an antibody panel including IgG, IgA, and IgM. However, a positive test may not reflect current infection or be specific to C. albicans as antibodies may be generated with exposure to commensal yeasts. Serum antibody testing can’t differentiate between mucosal colonization and deep-seated infection (Labcorp 2022).
Antibodies may not appear until the infection has advanced but microbial metabolites may be useful in early detection of overgrowth including D-arabinitol (DA), a polyol produced by most Candida species including C. albicans. An elevated ratio of D-arabinitol to creatinine above 3.9 M/mg/dL three days or more after onset of fungemia was associated with increased mortality in hospitalized patients. Researchers note that the DA:creatinine ratio is useful for the initial diagnosis and monitoring of Candida infection (Lain 2008).
A blood culture may help identify a systemic severe Candida infection (Kato 2019), and a stool culture can help identify overgrowth. C. albicans may be found in the stool under normal circumstances, but not in excess quantities or in pathogenic hyphae form until infection is present (Schulze 2009).
PCR and antigen-based testing for beta-D-glucan (BDG) and Candida mannan may have better sensitivity than standard blood culture tests (Ahmad 2012). A prospective observational study of hospitalized patients found that the BDG test combined with Candida albicans germ tube antibody test had high sensitivity and was useful in determining the need for continued antifungal therapy (Martínez-Jiménez 2015). Assessing alcohol levels following a glucose challenge may help identify gastrointestinal C. albicans overgrowth due to the fermentation of glucose into alcohol (Gaby 2011).
Chronic infection with C. albicans may be a sign of hypochlorhydria which can be explored further (Murray 2012). The use of essential oils may be effective in fighting Candida proliferation, including jasmine, rosemary, clove, and cinnamon (El-Baz 2021).
References
Ahmad, S, and Z Khan. “Invasive candidiasis: a review of nonculture-based laboratory diagnostic methods.” Indian journal of medical microbiology vol. 30,3 (2012): 264-9. doi:10.4103/0255-0857.99482
Brown, Gordon D et al. “Hidden killers: human fungal infections.” Science translational medicine vol. 4,165 (2012): 165rv13. doi:10.1126/scitranslmed.3004404
El-Baz, A. M., et al. "Back to Nature: Combating Candida albicans Biofilm, Phospholipase and Hemolysin Using Plant Essential Oils. Antibiotics 2021, 10, 81." (2021).
Figueiredo, Rodrigo T, and Josiane S Neves. “Eosinophils in fungal diseases: An overview.” Journal of leukocyte biology vol. 104,1 (2018): 49-60. doi:10.1002/JLB.4MR1117-473R
Gaby, A. (2011). Nutritional medicine. Concord, N.H: Fritz Perlberg Publishing.
Kato, Hideaki et al. “Mortality and risk factor analysis for Candida bloodstream infection: A multicenter study.” Journal of infection and chemotherapy : official journal of the Japan Society of Chemotherapy vol. 25,5 (2019): 341-345. doi:10.1016/j.jiac.2019.01.002
Labcorp. Candida Antibodies, IgA, IgG, IgM. https://www.labcorp.com/tests/163135/i-candida-i-antibodies-iga-igg-igm-elisa
Laín, Ana et al. “Contribution of serum biomarkers to the diagnosis of invasive candidiasis.” Expert review of molecular diagnostics vol. 8,3 (2008): 315-25. doi:10.1586/14737159.8.3.315
Martínez-Jiménez, M Carmen et al. “Combination of Candida biomarkers in patients receiving empirical antifungal therapy in a Spanish tertiary hospital: a potential role in reducing the duration of treatment.” The Journal of antimicrobial chemotherapy vol. 70,11 (2015): 3107-15. doi:10.1093/jac/dkv241
Murray, Michael T., and Joseph Pizzorno. The encyclopedia of natural medicine third edition. Simon and Schuster, 2012.
Schulze, Jürgen, and Ulrich Sonnenborn. “Yeasts in the gut: from commensals to infectious agents.” Deutsches Arzteblatt international vol. 106,51-52 (2009): 837-42. doi:10.3238/arztebl.2009.0837