Facial rash

Facial rash is any erythematous, scaly, papular, pustular, vesicular or pigmented eruption centred on the face. Most are common inflammatory dermatoses. The face also carries photosensitive, connective tissue and infective rashes with systemic consequences, and eruptions near the eye, nose and lip can threaten vision or spread to the cavernous sinus.

Anatomy. Sebaceous sites (glabella, nasolabial folds, eyebrows, chin) favour seborrhoeic dermatitis, acne and rosacea. Eyelid skin is thin and reacts to allergens and irritants. Sun exposed convexities (cheeks, nose, forehead) favour photosensitive and lupus rashes. Valveless facial veins drain to the cavernous sinus, so infection of the nose, upper lip and medial cheek can spread intracranially.

Morphology. Eczematous (scaly, itchy, ill defined), papulopustular, erythematous with telangiectasia and flushing, vesicular or bullous, violaceous, annular or plaque like, nodular, and pigmented.

Distribution. A malar rash that spares the nasolabial folds suggests lupus, whereas involvement of the folds suggests dermatomyositis, seborrhoeic dermatitis or rosacea. Photodistributed rashes spare the upper eyelids, retroauricular skin and submental skin. A unilateral dermatomal rash suggests zoster.

Temporal pattern. Acute onset over hours to days occurs in contact reactions, infection, angioedema and drug eruptions. Chronic relapsing courses occur in rosacea, seborrhoeic dermatitis, atopic dermatitis and lupus.

Key distinctions. Pustules without comedones suggest rosacea or perioral dermatitis. A hot, sharply demarcated, tender plaque with fever suggests erysipelas. Violaceous eyelid change with periorbital oedema and proximal weakness suggests dermatomyositis. A burning facial eruption with rebound flares after stopping a topical corticosteroid suggests steroid damaged skin.

History

• Onset, tempo, itch, pain or burning, and course. Triggers: sun, heat, alcohol, spicy food, emotion, cosmetics, sunscreens, hair dye, spectacle frames, plants and pets.
• Topical corticosteroid use on the face, including lightening creams and inhaled or nebulised steroid, and recent change in skin care products.
• Drugs started in the preceding weeks: thiazides, doxycycline, amiodarone, NSAIDs, hydroxychloroquine, isoniazid, lithium, EGFR inhibitors, vemurafenib, sulphonamides, anticonvulsants and allopurinol.
• Systemic features: fever, joint pain, mouth ulcers, hair loss, Raynaud phenomenon, proximal weakness, dysphagia, dyspnoea, eye symptoms, flushing with diarrhoea or wheeze, weight loss and night sweats.
• Contacts with infectious illness, vaccination status, travel, HIV risk, immunosuppression, atopy, pregnancy and occupation.

Examination

• Vital signs and perfusion first. Lesion morphology, scale, vesicles, pustules, comedones, telangiectasia, rhinophyma, annular edges, periorbital oedema and heliotrope colour. Test blanching with a glass.
• Distribution relative to folds and sun exposure, and a Wood lamp when tinea or erythrasma is possible.
• Eyes (conjunctivitis, blepharitis, keratitis, proptosis, ophthalmoplegia), nasal tip lesions (Hutchinson sign), ears, scalp, oral mucosa and lips.
• Neck V, hands (Gottron papules, nail fold telangiectasia, mechanic's hands), joints, lymph nodes and proximal muscle power.
• Facial nerve function, trigeminal sensation, blood pressure and urine dipstick.
• Signs of Cushing syndrome, hirsutism and hepatosplenomegaly.

Red flags

• Erythema or swelling around the eye with proptosis, painful or restricted eye movement, chemosis, visual loss or headache (orbital cellulitis, cavernous sinus thrombosis).
• Vesicles on the nasal tip or forehead, or an eye symptom with a dermatomal rash (herpes zoster ophthalmicus), or ear involvement (Ramsay Hunt syndrome).
• Punched out erosions or vesicles on atopic skin with fever (eczema herpeticum).
• Sudden swelling of lips, tongue or eyelids with wheeze, stridor or hypotension.
• Mucosal erosions, blistering or skin pain after a new drug (Stevens-Johnson syndrome, DRESS).
• Rash with hypotension, confusion or nonblanching spots (sepsis).
• Pain out of proportion, rapid spread or bullae (necrotising infection).
• Proximal weakness, dysphagia or dyspnoea (dermatomyositis).
• Malar rash with haematuria, proteinuria, cytopenia, serositis or neurological features (lupus).
• Child with fever for 5 days or more, conjunctivitis, and lip and limb changes (Kawasaki disease).
• Flushing with diarrhoea and wheeze (carcinoid syndrome).
• A nonhealing, pearly, ulcerated or bleeding facial lesion.

Special groups

• Children: atopic dermatitis, impetigo, slapped cheek rash, hand foot and mouth disease, molluscum contagiosum, perioral dermatitis after steroid exposure, infantile haemangioma, Kawasaki disease and juvenile dermatomyositis.
• Pregnancy: acne, melasma and rosacea flares. Avoid retinoids, tetracyclines, oral azoles and methotrexate. Use azelaic acid, mild corticosteroid and erythromycin.
• Older adults: actinic keratosis, basal cell carcinoma, cutaneous lupus, rosacea and pemphigoid.
• Skin of colour: erythema is less visible, so look for warmth, scale and hyperpigmentation. Lupus, sarcoidosis and leprosy are easily missed.
• Immunocompromised: severe seborrhoeic dermatitis, extensive molluscum, and disseminated fungal infection.
• Region specific: leprosy, cutaneous leishmaniasis, mpox, measles, histoplasmosis and penicilliosis in HIV.

Eczematous and inflammatory

• Seborrhoeic dermatitis.
• Atopic dermatitis.
• Allergic contact dermatitis, including airborne and eyelid dermatitis.
• Irritant contact dermatitis.
• Perioral dermatitis.
• Steroid damaged face.
• Rosacea (erythematotelangiectatic, papulopustular, phymatous, ocular).
• Acne vulgaris.
• Facial psoriasis.
• Lichen planus.
• Urticaria and angioedema.
• Granuloma faciale.
• Sarcoidosis, including lupus pernio.
• Sweet syndrome.
• Pityriasis alba.

Photosensitive and autoimmune

• Systemic lupus erythematosus (acute malar rash).
• Subacute cutaneous lupus.
• Discoid lupus erythematosus.
• Dermatomyositis and juvenile dermatomyositis.
• Mixed connective tissue disease.
• Systemic sclerosis.
• Pemphigus foliaceus and pemphigus erythematosus.
• Polymorphic light eruption.
• Chronic actinic dermatitis.

Infective

• Erysipelas and facial cellulitis.
• Orbital and periorbital cellulitis.
• Impetigo.
• Folliculitis and sycosis barbae.
• Herpes simplex and eczema herpeticum.
• Herpes zoster, including ophthalmicus and Ramsay Hunt syndrome.
• Varicella.
• Parvovirus B19 infection.
• Measles and rubella.
• Roseola infantum.
• Hand, foot and mouth disease.
• Mpox.
• Molluscum contagiosum.
• Tinea faciei and tinea incognito.
• Demodex folliculitis.
• Scarlet fever.
• Kawasaki disease.
• Dengue.
• Secondary syphilis.
• Leprosy.
• Cutaneous leishmaniasis.
• Lupus vulgaris.
• Disseminated cryptococcosis, histoplasmosis and penicilliosis in HIV.

Vascular and flushing

• Carcinoid syndrome.
• Mastocytosis.
• Menopausal flushing.
• Polycythaemia vera.
• Superior vena cava syndrome.
• Drug related flushing (niacin, calcium channel blockers, vancomycin infusion reaction, alcohol with metronidazole).
• Cushing syndrome (facial plethora).
• Phaeochromocytoma and medullary thyroid carcinoma.

Neoplastic

• Basal cell carcinoma.
• Squamous cell carcinoma and actinic keratosis.
• Lentigo maligna.
• Cutaneous T cell lymphoma.
• Angiosarcoma of the face and scalp.
• Kaposi sarcoma.
• Leukaemia cutis.

Other

• DRESS.
• Stevens-Johnson syndrome and toxic epidermal necrolysis.
• Fixed drug eruption.
• Thyroid eye disease and nephrotic or nephritic periorbital oedema.
• Hypothyroid facies.

Step 1. Emergencies. Assess airway, perfusion and eye involvement. Isolate suspected measles or varicella.

Step 2. Morphology and distribution. Combine pattern, folds, sun exposure, tempo and associated features.

Step 3. Bedside tests

• Potassium hydroxide microscopy and fungal culture of scale from the active edge, taken before any antifungal or corticosteroid.
• Vesicle swab for herpes simplex and varicella zoster PCR, bacterial swab for crusted or pustular skin, and Demodex scraping (a high mite density supports but does not prove a causal role).
• Wood lamp, dermoscopy, urine dipstick for blood and protein, and blood pressure.

Step 4. Blood tests when systemic disease is possible

• Full blood count with differential, ESR, CRP, urea, creatinine, liver tests, creatine kinase, glucose and urinalysis.
• Lupus: ANA, anti dsDNA, extractable nuclear antigens (Ro, La, Sm), C3 and C4, antiphospholipid antibodies, and urine protein to creatinine ratio. A positive ANA occurs in 5 to 20% of healthy people, so interpret it with the clinical picture.
• Dermatomyositis: creatine kinase, aldolase, liver enzymes, LDH, myositis specific antibodies (Mi-2, TIF1 gamma, NXP2, MDA5), muscle MRI or electromyography, and malignancy screening with CT chest, abdomen and pelvis.
• HIV test in extensive molluscum, severe seborrhoeic dermatitis or atypical rash. Syphilis serology.
• Flushing: urinary 5-hydroxyindoleacetic acid (carcinoid) and serum tryptase over 20 ng/mL (mastocytosis).
• Parvovirus B19 IgM, measles IgM and RNA PCR, and dengue NS1 antigen or PCR as the setting suggests.

Step 5. Targeted tests

• Skin punch biopsy (4 mm) from a lesion edge for any facial rash persisting over 4 weeks, not responding to treatment, or suspected lupus, sarcoidosis, granulomatous disease, lymphoma or skin cancer. Add direct immunofluorescence for lupus and pemphigus.
• Patch testing (baseline and cosmetic series) after 1 to 2 weeks without topical corticosteroid. Photopatch testing when photoaggravation is present.
• Slit skin smear (leprosy), smear and PCR (leishmaniasis), cryptococcal antigen and fungal culture or biopsy for umbilicated papules with fever in HIV.
• Orbital cellulitis: contrast CT of orbits and sinuses, blood cultures, and ophthalmology review. Cavernous sinus thrombosis: CT or MR venography.

Limits. Biopsies of seborrhoeic dermatitis and rosacea are nonspecific. Prior corticosteroid use alters morphology and makes fungal tests falsely negative. Irritant patch reactions can mislead. A negative ANA argues strongly against lupus but a positive result alone does not confirm it.

Immediate

• Anaphylaxis or airway angioedema: adrenaline 0.5 mg (0.5 mL of 1 mg/mL) intramuscularly into the lateral thigh, repeated every 5 minutes if no response, with oxygen and intravenous fluid.
• Orbital cellulitis: admit. Give ceftriaxone 2 g intravenously every 12 hours plus metronidazole 500 mg intravenously every 8 hours, adding vancomycin 15 to 20 mg/kg intravenously every 8 to 12 hours when MRSA is likely. Urgent ENT and ophthalmology review, with drainage of subperiosteal abscess for threatened vision.
• Eczema herpeticum: aciclovir 5 to 10 mg/kg intravenously every 8 hours, changing to oral aciclovir when improving. Adjust for creatinine clearance (25 to 50 mL/min every 12 hours; 10 to 25 mL/min every 24 hours; under 10 mL/min half dose every 24 hours) and maintain hydration.
• Herpes zoster ophthalmicus: aciclovir 800 mg orally five times daily for 7 days, or valaciclovir 1 g orally three times daily for 7 days (30 to 49 mL/min 1 g every 12 hours; 10 to 29 mL/min 1 g once daily; under 10 mL/min 500 mg once daily). Same day ophthalmology review.
• Stevens-Johnson syndrome, toxic epidermal necrolysis, DRESS and necrotising infection: admission, stop the suspected drug, and specialist care.
• Sepsis: sepsis resuscitation and intravenous antibiotics within 1 hour.

General measures. Use a soap substitute and emollient, apply broad spectrum sunscreen SPF 30 to 50 daily, avoid triggers, and stop unnecessary cosmetics.

Dermatoses

• Seborrhoeic dermatitis: ketoconazole 2% cream once or twice daily for 4 weeks, then once or twice weekly. Hydrocortisone 1% cream once daily for up to 7 days for inflamed skin (maximum 14 days on the face). Tacrolimus 0.1% ointment or pimecrolimus 1% cream twice daily as a steroid sparing option. Severe disease in HIV improves with antiretroviral therapy.
• Atopic dermatitis: emollients, hydrocortisone 1% once or twice daily for 7 to 14 days, and tacrolimus 0.03% to 0.1% ointment or pimecrolimus 1% cream twice daily. Flucloxacillin 500 mg orally four times daily for 5 to 7 days for secondary infection.
• Contact dermatitis: remove the allergen. Hydrocortisone 1% or mometasone furoate 0.1% once daily for up to 7 days (eyelids: hydrocortisone 1% for up to 7 days, or tacrolimus 0.1% twice daily). Severe acute dermatitis with facial swelling: prednisolone 30 to 40 mg orally daily for 5 to 7 days.
• Rosacea: sunscreen and trigger avoidance. Metronidazole 0.75% cream or gel twice daily (or 1% once daily) for 8 to 12 weeks. Azelaic acid 15% gel twice daily. Ivermectin 1% cream once daily for up to 12 weeks, repeated if relapse. Brimonidine 0.33% gel once daily for persistent erythema (rebound flushing; avoid with MAO inhibitors). Oral doxycycline 100 mg once daily for 6 to 12 weeks, or 40 mg modified release once daily for 12 to 16 weeks. Isotretinoin 0.25 to 0.5 mg/kg daily for refractory disease (specialist). Ocular rosacea: lid hygiene, warm compresses and ophthalmology review. Avoid topical corticosteroids.
• Perioral dermatitis: stop all topical corticosteroids and heavy creams, and expect a flare for 2 to 4 weeks. Metronidazole 0.75% twice daily or pimecrolimus 1% cream twice daily for 8 weeks. Doxycycline 100 mg orally once or twice daily for 6 to 8 weeks, or erythromycin 250 to 500 mg orally twice daily in pregnancy and under 12 years.
• Steroid damaged face: step down to hydrocortisone 1% for 1 to 2 weeks then stop, or stop at once with pimecrolimus 1% cream or tacrolimus 0.03% ointment twice daily and doxycycline 100 mg daily for 6 to 8 weeks. Counsel that rebound lasts weeks to months.
• Acne: benzoyl peroxide 2.5 to 5% with a topical retinoid, and doxycycline 100 mg daily for moderate disease, as detailed for acne.
• Tinea faciei: terbinafine 1% cream once or twice daily for 2 weeks, or clotrimazole 1% cream 2 to 3 times daily for 2 to 4 weeks, continued 1 to 2 weeks after clearing. Extensive disease: terbinafine 250 mg orally once daily for 2 weeks (125 mg daily if creatinine clearance is under 50 mL/min; avoid in pregnancy and active liver disease).

Infections

• Impetigo: mupirocin 2% ointment three times daily for 5 days, or fusidic acid 2% cream three times daily for 5 to 7 days. Extensive disease: flucloxacillin 500 mg orally four times daily for 5 to 7 days (clarithromycin 250 to 500 mg twice daily if penicillin allergic).
• Erysipelas and facial cellulitis: flucloxacillin 500 mg to 1 g orally four times daily for 5 to 7 days, or 1 to 2 g intravenously every 6 hours when severe (clarithromycin 500 mg twice daily for 7 days if penicillin allergic). Admit facial infections involving the nose, upper lip or periorbital skin.
• Herpes labialis: valaciclovir 2 g orally twice daily for 1 day at the first sign (1 g twice daily if creatinine clearance is 30 to 49 mL/min; 500 mg twice daily if 10 to 29 mL/min), or aciclovir 400 mg orally three times daily for 5 days.
• Herpes zoster not involving the eye: aciclovir 800 mg orally five times daily for 7 days or valaciclovir 1 g orally three times daily for 7 days, started within 72 hours of the rash.
• Molluscum contagiosum: usually self limiting in immunocompetent people. Cryotherapy, curettage or potassium hydroxide 5 to 10% solution applied daily until mild irritation. Extensive disease in HIV needs antiretroviral therapy.
• Measles: supportive care, isolation, and vitamin A 200,000 IU orally once daily for 2 days (12 months or over; 100,000 IU at 6 to 11 months; 50,000 IU under 6 months).
• Parvovirus B19: supportive care with paracetamol, and urgent obstetric review in pregnancy.
• Kawasaki disease: urgent paediatric admission for intravenous immunoglobulin 2 g/kg as a single infusion over 10 to 12 hours, with aspirin directed by the specialist.
• Disseminated fungal infection in HIV: admission, liposomal amphotericin B 3 to 5 mg/kg intravenously once daily for 2 weeks, then itraconazole 200 mg orally twice daily for 10 weeks and 200 mg daily as maintenance (histoplasmosis and penicilliosis). Cryptococcosis needs lumbar puncture and a specialist regimen.

Autoimmune and other

• Cutaneous and systemic lupus: sunscreen and smoking cessation. Hydroxychloroquine 200 to 400 mg orally daily (maximum 5 mg/kg of actual body weight daily; reduce when eGFR is under 30 mL/min/1.73 m2), with a baseline eye examination and annual retinal screening after 5 years. Topical mometasone furoate 0.1% once daily for up to 2 weeks, or tacrolimus 0.1% ointment twice daily. Flares with organ involvement: prednisolone 0.5 to 1 mg/kg daily and rheumatology review.
• Dermatomyositis: prednisolone 0.5 to 1 mg/kg orally daily (maximum 80 mg daily) with a steroid sparing agent (methotrexate 15 to 25 mg weekly with folic acid 5 mg weekly on a different day, or azathioprine 1 to 3 mg/kg daily after TPMT or NUDT15 testing), photoprotection and malignancy screening. Admit for dysphagia or respiratory involvement.
• Carcinoid syndrome: octreotide 100 to 200 micrograms subcutaneously three times daily as a bridge, or the long acting form 20 to 30 mg intramuscularly every 4 weeks (specialist).
• Mastocytosis flushing: cetirizine 10 mg and ranitidine alternative (famotidine 20 mg) orally twice daily, trigger avoidance, and an adrenaline autoinjector.
• Skin cancer: excision with margins (basal cell carcinoma 4 mm for low risk disease, squamous cell carcinoma 4 to 6 mm), or Mohs surgery for facial sites.

Monitoring. Review at 2 to 4 weeks (8 to 12 weeks for rosacea). Check skin atrophy and telangiectasia with topical corticosteroid. Reassess the diagnosis if there is no response to 4 weeks of treatment, and biopsy.

Referral and escalation. Same day ophthalmology or ENT for orbital signs or ophthalmic zoster. Dermatology within 2 weeks for suspected lupus, dermatomyositis, sarcoidosis, lymphoma or skin cancer, and routinely for refractory dermatoses. Rheumatology for connective tissue disease. HIV services for HIV associated disease. Paediatric review for Kawasaki disease.

Admission criteria. Orbital or periorbital cellulitis, facial infection near the cavernous sinus, eczema herpeticum, ophthalmic zoster with eye signs, sepsis, severe cutaneous drug reaction, angioedema, dermatomyositis with dysphagia or dyspnoea, lupus with organ involvement, and Kawasaki disease.

Disposition. Most patients are managed in primary care. Safety net advice: return for eye pain or swelling, visual change, spreading redness with fever, new blisters on the nose or forehead, mouth or eye sores, muscle weakness, breathing difficulty or swelling of lips or tongue.