Tinea capitis: diagnosis and recommended management

Cause and transmission Several different dermatophytes can cause tinea capitis but the current inner-city epidemic is attributed to Trichophyton tonsurans, which is anthropophilic, ie is easily transmitted between humans. It is also an endothrix, meaning the spores invade the hair shaft, as opposed to an ectothrix, which rests on the surface. Studies from central London suggest a prevalence of around 2.5 per cent, with up to one in four children infected in one class examined.1 Prior to T. tonsurans gaining ground in the UK, Microsporum canis was the most common cause of tinea capitis. An ectothrix and zoophilic, M. canis is usually transmitted animal to human rather than person to person. Typically this fungus is contracted on holiday from contact with infected stray cats or dogs. Clinical presentation For inner-city children, it is reasonable to presume scalp problems are due to tinea capitis until proven otherwise. Although obvious indicators such as a scaly patch of hair loss are easily spotted, the presently common T. tonsurans is responsible for a range of clinical presentations and so diagnosis can be a little more challenging. Clinical presentations include: scaly circular patches of hair loss, pustules, diffuse scale-like dandruff, and kerion with associated lymphadenopathy, an inflamed, boggy, painful tumour that may be studded with pustules (see Figure 1). It has a predilection for chil