Dorsal tongue porphyrin autofluorescence and Candida saprophytism: A prospective observational study

• Published in: PloS one 2019-09, Vol.14 (9), p.e0223072-e0223072
• Main Authors: Petruzzi, Massimo, Della Vella, Fedora, Cassandro, Andrea, Mosca, Adriana, Di Comite, Mariasevera, Contaldo, Maria, Grassi, Felice Roberto, Lauritano, Dorina
• Format: Article
• Language: English
• Subjects: Adult; Aged; Biofilms; Biology and Life Sciences; Biopsy; Candida; Candida - isolation & purification; Candida - metabolism; Candidiasis, Oral - diagnosis; Candidiasis, Oral - microbiology; Correlation analysis; Female; Fluorescence; Humans; Interdisciplinary aspects; Male; Mathematical analysis; Medical equipment; Medicine; Medicine and Health Sciences; Middle Aged; Molecular Imaging - methods; Neurosciences; Observational studies; Optical Imaging - methods; Physical Sciences; Porphyrins - chemistry; Porphyrins - metabolism; Predictive Value of Tests; Prospective Studies; Research and Analysis Methods; Saprophytism; Sensitivity; Sensitivity and Specificity; Tongue; Tongue - diagnostic imaging; Tongue - microbiology
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0223072

To investigate the correlation between the dorsal tongue porphyrin autofluorescence, revealed using VELscope, and Candida saprophytism. Consecutive patients underwent an autofluorescence examination by the VELscope device to establish the presence or absence of porphyrin fluorescence. A tongue swab was collected for the Candida cultural test. Sensitivity, specificity, accuracy, negative predictive value and positive predictive value were calculated considering the oral swab as the gold standard. The degree of agreement between the two tests was calculated using Cohen's K coefficient. One hundred twenty-six patients were enrolled. Porphyrin fluorescence method showed a sensitivity of 78%, specificity of 76% and an accuracy of 78%. Negative predictive value and positive predictive value were respectively 90% and 59%. The strength of agreement between the two methods resulted to be moderate (k = 0.551). Off-label use of tongue autofluorescence examination to detect the presence of Candida species is characterized by a loss of porphyrin fluorescence. The high negative predictive value of porphyrin fluorescence loss suggests its use in preliminary selection of Candida carriers, in order to plan preventive and therapeutic strategies.