Tinea capitis: a painful scalp lesionBMJ 2010; 340 doi: https://doi.org/10.1136/sbmj.b4938 (Published 20 January 2010) Cite this as: BMJ 2010;340:b4938
- Adam Duckworth, foundation year 2 doctor1,
- Ingrid Salvary, consultant dermatologist2
- 1Norfolk and Norwich University Hospital, Norwich NR4 7UY
- 2James Paget University Hospital, Great Yarmouth, Norfolk NR31 6LA
A 9 year old girl presents to the emergency department with a painful lesion on her scalp. It was initially a small, erythematous, scaly, pruritic eruption but gradually increased in size over the previous six weeks despite several courses of antibiotics from her general practitioner. Physical examination showed a girl in good health, with a 15 cm by 15 cm extremely tender, boggy inflammatory mass on the crown of her head accompanied by localised alopecia (hair loss) and cervical lymphadenopathy (fig 1⇓). She is apyrexial with a white cell count 16.5×109/l and C reactive protein 28 mg/l.
(1) What is your working clinical diagnosis?
(2) What organism is most likely to be responsible?
(3) What investigations would you like to perform?
(4) What is the treatment?
(1) This is an example of a fungal kerion, which is an inflammatory reaction to tinea capitis (scalp ringworm). The differential diagnosis of a kerion includes scalp abscess and dissecting cellulitis. The differential diagnosis of non-inflammatory tinea capitis is seborrhoeic dermatitis, atopic dermatitis, impetigo, and pustular or plaque psoriasis.
(2) The predominant pathogen …