A 7 year old boy with boggy swelling of the scalp with multiple discharging sinuses with cervical lymphadenopathy with easily pluckable hair. What would be done for diagnosis?
KOH mount The patient gives classic presentation of Kerion (Tinea capitis). Tinea capitis It is an infection caused by dermatophyte fungi usually species of the genera (microsporum and Trichophyton)) of scalp hair follicles and the surrounding skin. It is predominantly a disease of preadolescent children. The main pathogens are anthrophilic organisms with Trichophyton Tonsurans accounting for > 90% cases. There are two patterns of the disease : Endothrix --> Spores (anthroconidia) within the hair shaft Ectothrix --> Hyphae and anthrocondia outside the hair shaft Investigation needed in cases of Tinea capitis Microscopy Potassium hydroxide (KOH) wet mounts Microscopy provides the most rapid diagnosis. Samples are taken from the site of infection and are demonstrated using 10% (KOH). - KOH dissolves the keratin and the fungus is easily demonstrated using the low power objective. - The slide is examined for fungal hyphae and spores Cultures - Cultures need to be done when KOH mount is negative or when it is necessary to identify the .fungal species. - Fungi are cultured on sabroud's dextrose agar. - Culture is more sensitive than microscopy and the result may be positive even when microscopy is negative. Wood's ultraviolet light - When wood's ultraviolet light is shown on hairs they produce green fluorescence with microspora infection but will .fail to identify Trichophyton tonsurans.
Pus for culture
KOH mount
Biopsy
None of the above