Detection of Dermatophytes in Subclinically Involved Nails by Polymerase Chain Reaction in Patients with Skin Dermatophytosis: A Prospective Observational Study.
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引用次数: 0
Abstract
Context: Patients with skin dermatophytosis can have subclinical dermatophytes in the nails, which can easily be missed on clinical examination. Dermatophytes may not be isolated from normal-appearing nails by KOH and culture, where it can serve as a reservoir for recurrent infection. Detection can be made by polymerase chain reaction (PCR), a more sensitive and faster technique.
Aims: To detect the presence of dermatophytes in clinically unaffected nails by PCR in patients with skin dermatophytosis and to evaluate the diagnostic performance of KOH, culture, and PCR in detecting subclinical nail involvement.
Materials and methods: In this prospective observational study, 120 patients with skin KOH positivity had their nail clippings collected and sent for KOH, PCR, and culture. Results were tabulated, and statistical analysis was done.
Results: Out of 120 patients, nail KOH revealed that 39 patients (32.5%) tested positive for dermatophytes, while 81 (67.5%) tested negative. Nail culture on Sabouraud dextrose agar (SDA) and dermatophyte test medium (DTM) showed dermatophyte growth in 44 patients: Trichophyton mentagrophytes (15.1%), Trichophyton rubrum (12.1%), Trichophyton tonsurans (4.2%), and unidentified dermatophytes (2.4%). PCR identified dermatophytes in 57 patients (47.5%). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of KOH compared to PCR were found to be 68.4%, 100%, 100%, 77.8%, and 85% respectively; the same parameters for culture versus PCR were found to be 77.2%, 96.8%, 95.7%, 82.4%, and 87.5%, respectively, and for PCR versus culture were found to be 100%, 82.9%, 77.2%, 100%, and 89.2%, respectively.
Conclusion: In patients with dermatophyte infection, nail PCR can detect subclinical infection in the nail, which may serve as a reservoir for ongoing infection and recurrence.
期刊介绍：
The journal publishes information related to skin-pathology and different modes of therapeutics, including dermatosurgery and cosmetic dermatology. Likewise, it carries articles on leprosy, STI and HIV/AIDS. The editorial board encourages the authors to publish articles addressing emerging techniques and developments in the subject specialty, in the form of Original investigations, Narrative and Systematic Reviews as well as Case Reports. The journal aims at publishing Editorials and Commentaries from eminent personalities on a regular basis.
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