Fungal Infection by Site, Tinea Capitis
Conditions
Keywords
Tinea capitis, antifungal resistance, dermatophyte, KOH
Brief summary
Tinea capitis is a common dermatophyte infection of the scalp in children aged 0-9 years .The prevalence of tinea capitis in Egypt is 0.4% and higher in public than private schools, Boys were more affected than girls according to children by 5:1 ratio , It is more prevalent in those who live in urban areas, large families, low socioeconomic level, crowded living conditions and immunocompromised people . Tinea capitis is caused by dermatophyte fungi Trichophyton and Microsporum genera. These fungi are classified as: anthropophilic, zoophilic, and geophilic according to the route of infection. These fungi invade the hair shaft in two routes: ectothrix and endothrix . T.tonsurans and T.violaceum are reported to be the most common cause of tinea capitis
Detailed description
Clinical types of tinea capitis include : scaly type (characterized by fine scaling and circular alopecia), black dot (characterized by non-inflammatory patches with broken-off, swollen hair stubs), tinea agminate (patchy alopecia with scattered pustules or low-grade folliculitis), kerion (painful, boggy, inflammatory masses with alopecia, often confused with bacterial abscess) and favus (scutula, mousy odor) . Tinea incognito (steroid modified tinea) refers to dermatophytosis that has lost their usual clinical appearance due to the use of steroids. The main clinical feature of dermatophyte scalp infections is the appearance of scaling of the scalp skin, which is associated with a variable degree of inflammation and itching . In some cases, the infection closely resembles seborrheic dermatitis or dandruff of the scalp. A pathognomonic feature is hair loss; hair often breaks a few millimeters or more above the skin surface. Broken or infected hairs are also slightly swollen and have a dull appearance . Trichoscopy is a non-invasive and very useful technique for the diagnosis and follow-up of hair and scalp disorders. The presence of certain trichoscopic features allows accurate identifying of tinea capitis. In tinea capitis, specific signs can be seen like comma hair, corkscrew hair, bar code-like hair and zigzag hair . In tinea incognito trichoscopic finding include erythema, scaling, bent hair, Morse code hair, and micropustules . Mycological examination was first performed using Potassium Hydroxide(KOH) to confirm the diagnosis of tinea capitis where the patients with positive KOH were considered to have endothrix when observing arthroconidia inside the hair shaft and ectothrix when observing arthroconidia outside the hair shaft. The fungal culture also done to accurately recognize the organism through inoculation of samples on Sabouraud medium agar (SDA) with and without chloramphenicol(nonspecific medium) . And Dermasel medium agar act as specific medium. The increase in antifungal resistance has recently been observed worldwide and resistant strains of the dermatophytes T. rubrum and T. indotineae have spread globally, causing outbreaks of extensive, difficult to treat infections , so we need rapid and reliable diagnostic tools that provide clues regarding the causative organisms.
Interventions
DIAGNOSTIC_TESTDermoscopic examination: the findings are divided into pathognomic and non-specific signs
1. Pathognomic signs: comma hairs, corkscrew hairs, Morse code like hairs and zig-zag hairs. 2. Non-specific signs: black dots, broken hairs, perifollicular scaling and inter follicular erythema
DIAGNOSTIC_TESTDirect Microscopy (KOH) examination
1. Suspected lesions will be swabbed with 70% ethyl alcohol then scalp scraping using the blunt edge of a sterile surgical blade 2. Skin scales and crusts will be collected from the erythematous, peripheral, actively expanding edges of the lesions onto clean glass slides by scraping the inflamed lesions the scales will contain infected stumps of hair 3. Hair will be removed with the root intact (hair cutting will be avoided) 4. Specimen will be prepared by mounting the sample in (10-30%) of potassium hydroxide with 40% Dimethyle sulphoxide (DMSO) drops on the petri slide to soften the tissue, allowing a thin layer of cells to form.
DIAGNOSTIC_TESTFungal culture:
Specimen will be cultured on sabouraud's dextrose agar (SDA) at 25 -30 c for 2 to 4 weeks and another specimen will be cultured on a Dermasel agar base (Oxoid, UK), both supplemented with chloramphenicol and cycloheximide , staining the fungal colonies by Lactophenol cotton blue to help the examination of colonial morphology and microscopic examination of the macro-conidia allow the identification of the dermatophyte species and suitable treatment
DIAGNOSTIC_TESTAntifungal sensitivity:
Antifungal susceptibility testing will be performed to determine the specific sensitivity profiles of the fungal isolates. Antifungal susceptibility testing will be performed using seven antifungal agents: Terbinafine, Itraconazole, Griseofulvin, Fluconazole, Ketoconazole, Vorioconole and Miconazole. Dermatophytes colonies will be probed from Dermasel agar cultures.
Sponsors
Sohag University
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
1 Years to 18 Years
Healthy volunteers
No
Inclusion criteria
\- Both male and female in childhood period (1-18 years) with tinea capitis
Exclusion criteria
* Topical or systemic antifungal medications one month prior to enrollment in the study * Presence of systemic disease, such as hepatic,renal, cardiac, autoimmune diseases, or malignancy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Percentage of participants presenting with specific clinical patterns of tinea capitis | At the time of initial clinical evaluation | Clinical evaluation will be performed to identify and classify the presentation of tinea capitis lesions (e.g., scaly patches, black dots, kerion, favus). |
| Percentage of participants exhibiting specific dermoscopic features of tinea capitis | At the time of initial dermoscopic evaluation | Dermoscopic examination using a handheld dermatoscope to identify characteristic signs including comma hairs, corkscrew hairs, broken hairs, and scaling. |
| Prevalence of isolated fungal species among pediatric tinea capitis cases | At the time of initial sample collection and culture identification | Mycological evaluation including direct microscopic KOH preparation and fungal culture on agar media to isolate and identify the causative fungal pathogens. |
Countries
Egypt
Contacts
CONTACTNoha Shafik, Assistant professor
CONTACTWalaa Hemdan Abu Alhassan, Demonstrator
STUDY_CHAIRMohammed Abu El Hamd Ali
Faculty of Medicine , Sohag university
STUDY_CHAIRDoaa Gaber Abdelbaset
Faculty of Medicine , Sohag university
Outcome results
None listed