Fluorescence ofCandidain diagnosis of oral candidiasis.
BACKGROUND
Many pathogenic fungi fluoresce in hematoxylin and eosin stained sections, and Papanicolaou (PAP)-stained smears under ultraviolet illumination. In theory, this phenomenon could aid in the diagnosis of common fungal infections without the delay which is usually associated with special stains.


OBJECTIVE
To evaluate the role of fluorescence as a rapid screening technique for oral infections caused by Candida organisms in exfoliative smears of oral candidiasis.


METHODS
Two smears and one swab were collected from each of 62 clinically diagnosed cases of oral candidiasis. Smears were stained with (PAP) and periodic acid-Schiff stain (PAS). Both smears were evaluated under light microscopy (LM). Later, PAP smears were observed under fluorescent microscopy (PAP-FM). The swab was inoculated on Sabouraud's agar plate. Each technique was evaluated for sensitivity and specificity.


RESULTS
It was found that the PAS-stained smears were more reliable for detection of Candida species than other methods (sensitivity = 100%; specificity = 66.7%). The PAP-LM and PAP-FM showed less sensitivity (67.9% and 85.7%) and specificity (66.7% and 33.3%), respectively. Combined results of both light and fluorescent microscopy of PAP (LM + FM) showed increased sensitivity (89.3%) but reduced specificity (16.7%).


CONCLUSIONS
PAP autofluorescence is less sensitive than PAS, still it accentuates the distinct morphological features of Candida.
Department of Dentistry, Belagavi Institute of Medical Sciences, Belagavi, Karnataka, India.
L R
LR
Kumaraswamy Naik
Department of Oral Pathology and Microbiology, A B Shetty Memorial Institute of Dental Sciences, Mangalore, Karnataka, India.
Pushparaja
P
Shetty
Department of Microbiology, Subbaiah Institute of Medical Sciences, Subbaiah Medical College Hospital and Research Center, Shimoga, Karnataka, India.
M S
MS
Krishna Prasad
Department of Microbiology, K S Hegde Medical Academy, Nitte University, Mangalore, Karnataka, India.
Vimal Kumar
VK
Karnaker
Department of Oral Pathology and Microbiology, A B Shetty Memorial Institute of Dental Sciences, Mangalore, Karnataka, India.
Sarosh E
SE
Shroff
Department of Oral Pathology and Microbiology, A B Shetty Memorial Institute of Dental Sciences, Mangalore, Karnataka, India.
Lal P
LP
Madathil
D002175:Candida / Q000302:isolation & purification* / Q000472:pathogenicity; D002180:Candidiasis, Oral / Q000175:diagnosis*; D006801:Humans; D025301:Hyphae; D008853:Microscopy / Q000379:methods; D008856:Microscopy, Fluorescence / Q000379:methods*; D065006:Papanicolaou Test / Q000379:methods; D010503:Periodic Acid-Schiff Reaction / Q000379:methods; D012680:Sensitivity and Specificity; D013194:Staining and Labeling / Q000379:methods*