Key distinguishing features of the most common diagnoses
|Acne||Rosacea||Seborrhoeic Eczema||Impetigo||Perioral Dermatitis|
|Mainly Around Mouth||Possible||No||No||Possible||Yes|
|Papules and Pustules||Yes||Yes||No||Possible||Yes|
|Rapid Response to Antibiotics||No||Yes||No||Yes||Yes|
Possible:FBC, ESR/CRP, autoantibody screen, CPK.
Small Print:Viral or bacterial swabs, skin biopsy, muscle biopsy.
- FBC: WCC raised in any infection; may be normochromic, normocytic anaemia in SLE.
- ESR/CRP, autoantibody screen: ESR/CRP likely to be raised in infection and SLE; autoantibodies may be positive in the latter.
- CPK: Elevated in dermatomyositis.
- Viral or bacterial swabs: To help diagnosis in obscure cases or if secondary infection suspected.
- Skin biopsy; muscle biopsy: The former for suspected lupus vulgaris or sarcoidosis; the latter to confirm dermatomyositis.
- Do not underestimate the possible impact of a facial rash on a patient’s life. The cosmetic effect may be devastating.
- A therapeutic trial of antibiotics in acne may take up to 3 months to take effect – ensure the patient is aware of this.
- Remember that impetigo may simply represent superinfection of an underlying skin problem, such as eczema, which will require treatment in its own right.
- Check on OTC medication usage. In particular, remember that hydrocortisone 1% cream is available over the counter – inappropriate use might aggravate rosacea and perioral dermatitis.
- Parents are sensitised to non blanching rashes. They can be reassured that such a rash restricted to the face (indeed, restricted to the entire distribution of the superior vena cava) is not due to meningitis.
- A complaint of dramatic facial ‘sunburn’ in the elderly may well represent a phototoxic reaction – check the drug history.
- Beware the acute onset of unilateral unexplained facial erythema with mild oedema, especially in an elderly patient. This may well be the start of cellulitis or herpes zoster.
- Warn patients with facial zoster or herpes simplex infection near the eye to report any ocular problems.
- Acne excoriée may be a marker of significant psychiatric pathology.