sample collection for diagnosis of oral candida in pss patients

Diagnosis and Strain Identification of pSS-Related Oral Candida

Candidiasis is caused by Candida spp., which are opportunistic pathogens. Common strains include Candida albicans, Candida krusei, Candida glabrata, Candida parapsilosis, and Candida dubliniensis1. Opportunistic infections caused by Candida spp. include superficial Candida infections and invasive candidiasis. Invasive candidiasis mainly happens in immunocompromised individuals; for example, in patients with acquired immunodeficiency syndrome (AIDS), invasive candidiasis can significantly threaten the quality of life or even the life span2. Superficial Candida infection, such as mucocutaneous candidiasis, is more common in patients3. 
Oral candidiasis, a superficial Candida infection, is the most common human fungal infection. Candida albicans is a normal commensal of the mouth; the carriage rate of Candida spp. has been reported to range from 20% to 75% in the general population without any symptoms4. Overgrowth of Candida can lead to local discomfort in patients, such as the altered taste of sensation, burning sensation in the mouth, dysphagia due to poor nutrition, delayed recovery, and prolonged hospital stay. Long-term oral candidiasis can lead to severe invasive candidiasis, resulting in significant morbidity and mortality5. Oral candidiasis can also increase the risk of oral cancer5. Impaired salivary gland function is among the risk factors for oral candidiasis6. The initiation of infection is the adhesion of Candida to epithelial cell walls. This is followed by the proliferation and filamentation of Candida and the formation and maturation of biofilm7. Biofilms are extremely difficult to eradicate and are resistant to conventional antifungal treatment, making clinical treatment a challenge for biofilm-associated oral Candida infection7.
Primary Sj&#246;gren's syndrome (pSS) is an autoimmune disease that is characterized by dry mouth, dry eyes, and other systematic symptoms8. Dry mouth is the most frequent symptom of pSS. Saliva has important physiological antifungal functions. On the one hand, it can dilute and scour the mouth and thereafter remove organisms from the mucosa. On the other hand, saliva contains antimicrobial proteins, such as lactoferrin, sialoperoxidase, lysozyme, histidine-rich polypeptides, and specific anti-candidal antibodies, which can interact with the oral mucosa and prevent the overgrowth of Candida6. The reduced saliva flow may predispose pSS patients to oral candidiasis. An observational cross-sectional study conducted in 61 pSS patients found that 13.1% of pSS patients presented oral signs of candidiasis and colony forming unit (CFU)/mL of Candida albicans was found significantly and negatively correlated with levels of unstimulated whole saliva (UWS) and stimulated whole saliva (SWS)9.
The methods introduced in this manuscript can identify oral Candida infection based on characterized morphological attributes (e.g., the hyphae and yeast cells) in direct smear or after culturing10. The strain identification of the Candida using a Candida diagnostic agar is based on the formation of different colored colonies with varied morphology, which result from the cleavage of chromogenic substrates by species-specific enzymes11. In this manuscript, systematic methods for detecting oral Candida infection are introduced, including traditional oral Candida culture and rapid examination by potassium hydroxide (KOH) smear test and calcofluor white (CFW) staining assay10. Additionally, the antifungal susceptibility test, which can guide clinical oral Candida infection treatment, has been introduced. In actual situations, it is not necessary to perform all of the introduced methods in this manuscript; the oral Candida detection method(s) can be selected according to the purpose. The examination of oral Candida infection and the determination of Candida strains in pSS patients not only benefit the disease treatment but also help assess the characterization of oral candidiasis and the species profiles.

Author Spotlight: Oral Candida Diagnosis to Advance Clinical Treatment Regimen for pSS Patients

Examination of Oral Candida Infection in Primary Sj&#246;gren&#39;s Syndrome Patients

In this research, we present a protocol for the examination of oral candida infection in patients with primary Sjogren syndrome, which can be used for timely treatment to avoid infection-related complications. We provide a series of systematic, simple, and feasible methods for detecting oral candida infections, identifying candida strains, and testing the antifungal susceptibility of commonly-used drugs in patients with primary Sjogren's syndrome. Maybe our focus on the role of oral candida infection in the onset and the progression of primary Sjogren's syndrome pathologists in our future studies.

Sample Collection for Diagnosis of Oral Candida in pSS Patients

Research

JoVE Journal

Medicine

Primary Sj&#246;gren's syndrome (pSS) is an autoimmune disease characterized by symptoms such as dry mouth, dry eyes, and other systematic symptoms. Due ...

Candida Culture and Strain Identification in Patients with pSS

Rapid Detection of Oral Candida Infection in pSS Patients Using KOH Smear Test and CFW Staining Assay