Epidemiology and Diagnostic Perspectives of Dermatophytoses

Abstract

Dermatophytoses affect about 25% of the world population, and the filamentous fungus Trichophyton rubrum is the main causative agent of this group of diseases. Dermatomycoses are caused by pathogenic fungi that generally trigger superficial infections and that feed on keratinized substrates such as skin, hair, and nails. However, there are an increasing number of reports describing dermatophytes that invade deep layers such as the dermis and hypodermis and that can cause deep infections in diabetic and immunocompromised patients, as well as in individuals with immunodeficiency. Despite the high incidence and importance of dermatophytes in clinical mycology, the diagnosis of this type of infection is not always accurate. The conventional methods most commonly used for mycological diagnosis are based on the identification of microbiological and biochemical features. However, in view of the limitations of these conventional methods, molecular diagnostic techniques are increasingly being used because of their higher sensitivity, specificity and rapidity and have become more accessible. The most widely used molecular techniques are conventional PCR, quantitative PCR, multiplex PCR, nested, PCR, PCR-RFLP, and PCR-ELISA. Another promising technique for the identification of microorganisms is the analysis of protein profiles by MALDI-TOF MS. Molecular techniques are promising but it is necessary to improve the quality and availability of the information in genomic and proteomic databases in order to streamline the use of bioinformatics in the identification of dermatophytes of clinical interest.

Molecular identification and antifungal susceptibility patterns of dermatophytes isolated from companion animals with clinical symptoms of dermatophytosis

“…Dermatophytosis constitutes a major public health problem in several countries. The most common factors affecting the distribution and transmission of dermatophytic infections are animal contact, general hygiene and climatic conditions (30). This study highlighted the distribution of dermatophytes in dogs and cats with suspected dermatophytosis, the prevalence of infection in relation to sex and age, molecular diagnosis of dermatophytes and their susceptibility patterns.…”

“…The ITS rDNA regions of all samples were amplified in a PCR by the universal fungal primers V9G (5′-TTACgTCCCTgCCCTTTgTA-3′) and LS266 (5′-GCATTCCCAAACAACTCgACTC-3′) (21,30). Amplification was carried out by a PCR mixture containing 5 μL of 10x reaction buffer, 200 μM of dNTPs mixture, 0.25 μL of Taq polymerase (5 U/μL), 30 pmol of each forward and reverse primer, 2 μL of DNA template solution and ultrapure water up to a final volume of 50 μL.…”

“…The gold standard diagnostic techniques for the identification of dermatophytosis involve direct microscopic examination of clinical samples followed by in vitro isolation and identification (30). In addition, the use of PCR to diagnose dermatophytes in lesions in dogs and cats confirmed its usefulness, given that this can be done via infected samples.…”

New Perspectives in the Diagnosis and Management of Allergic Fungal Airway Disease

“…In some circumstances these commensal fungi can cause disease, through both allergenic and infective mechanisms. [30][31][32][33] The optimal growth temperature for most fungi is 25-30°C. Apart from the skin, potential for infection requires a greater degree of thermotolerance to allow them to germinate at body temperature.…”

Effects of Propolis on Infectious Diseases of Medical Relevance

“…Approximately 10% to 15% of people are infected by dermatophytes at some time in their life [ 97 ]. It is known that dermatophytoses have the ability to affect approximately 25% of the world population according to data from WHO, as well as to generate adults carrying the disease with completely asymptomatic characteristics in a percentage ranging from 30% to 70% [ 98 ]. In developed countries, dermatophytes are the main causes of onychomycosis identified with a frequency ranging from 80% to 90%.…”