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Astra Clinical Library

Dermatology

Practical dermatology guides for clinical decisions, with cited evidence, testing strategies, and actionable next steps.

34 guides

Dermatology

Basal Cell Carcinoma

Manage basal cell carcinoma by confirming clinically uncertain lesions histologically, separating low-risk from high-risk or recurrent tumors, selecting margin-controlled surgery when tissue preservation and clearance matter, and escalating unresectable disease to Hedgehog inhibition or cemiplimab.
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Wound Care

Pressure Injury

Manage pressure injury by immediately removing pressure and shear, correctly distinguishing mimics, characterizing tissue loss and exudate, identifying necrosis or deep infection, and selecting debridement, moisture-balanced dressings, negative-pressure therapy, or surgical management when indicated.
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Dermatology

Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis

Suspected SJS/TEN requires immediate withdrawal of plausible culprit drugs, clinical-pathologic confirmation, severity assessment, and early multidisciplinary supportive care. Management priorities are transfer to an experienced intensive or burn-care setting, meticulous mucosal surveillance, and prevention of ocular, infectious, respiratory, and genitourinary sequelae.
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Dermatology

Acanthosis Nigricans

Acanthosis nigricans should prompt etiologic triage rather than cosmetic treatment alone: most cases reflect obesity-associated insulin resistance, but abrupt generalized, mucosal, or nonobese presentations require evaluation for medication, endocrine, autoimmune, and malignant drivers.
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Dermatology

Acne Vulgaris

Treat acne by lesion phenotype, anatomic extent, scarring risk, and treatment response. Combine mechanistically distinct topical agents, avoid antibiotic monotherapy, use brief systemic antibiotic courses when needed, and move promptly to isotretinoin for severe, scar-forming, psychosocially burdensome, or treatment-refractory disease.
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Dermatology

Actinic Keratosis

Manage actinic keratosis by identifying lesions that require biopsy to exclude squamous cell carcinoma, then selecting lesion- or field-directed treatment based on burden, location, recurrence, tolerability, and cosmetic priorities.
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Dermatology

Alopecia Areata

Confirm nonscarring alopecia areata clinically and with trichoscopy, exclude infectious or inflammatory mimics when indicated, quantify scalp loss with SALT, and match localized disease to intralesional corticosteroids versus FDA-approved oral JAK inhibition for severe disease.
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Dermatology

Androgenetic Alopecia

Diagnose androgenetic alopecia by patterned miniaturization, use trichoscopy to distinguish competing alopecias, and initiate durable pharmacotherapy before irreversible density loss. Treatment selection differs substantially by sex, reproductive potential, distribution, and coexisting shedding or scarring disease.
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Dermatology

Atopic Dermatitis

A severity- and site-directed approach to atopic dermatitis prioritizes topical anti-inflammatory treatment, proactive relapse prevention, and timely systemic escalation when disease remains uncontrolled, sleep-disrupting, or extensive despite optimized topical care.
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Dermatology

Bullous Pemphigoid

Confirm bullous pemphigoid with perilesional direct immunofluorescence plus serology, assess extent and mucosal disease, and select treatment by disease control needs against corticosteroid toxicity in an often frail older population.
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Dermatology

Contact Dermatitis

Evaluate dermatitis through a structured exposure history, distinguish irritant from allergic mechanisms, use patch testing when contact allergy is plausible, and make relevance—not test positivity alone—the basis for avoidance and occupational interventions.
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Dermatology

Dermatitis Herpetiformis

Confirm suspected dermatitis herpetiformis with direct immunofluorescence of uninvolved perilesional skin, then treat the underlying gluten-sensitive enteropathy with a lifelong gluten-free diet while using dapsone for rapid control when pruritus or lesions remain active.
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Dermatology

Erythema Multiforme

Manage suspected erythema multiforme by first excluding Stevens-Johnson syndrome/toxic epidermal necrolysis, then identifying herpes simplex virus, respiratory infection, or medication exposure to guide testing, lesion-directed care, referral, and prevention of recurrent disease.
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Dermatology

Erythema Nodosum

Erythema nodosum requires confirmation of a septal panniculitis pattern and a targeted search for infection, sarcoidosis, inflammatory bowel disease, medication exposure, pregnancy, and systemic inflammatory disease. Management prioritizes identifying the trigger while treating pain and monitoring for atypical or persistent disease.
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Dermatology

Folliculitis

Folliculitis is best managed by separating uncomplicated bacterial disease from exposure-related, yeast-associated, eosinophilic, and scarring scalp disorders; culture, KOH examination, and biopsy are reserved for patterns in which the result changes treatment or prevents irreversible alopecia.
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Dermatology

Hidradenitis Suppurativa

Manage hidradenitis suppurativa by separating active inflammatory lesions from irreversible tunnels and scarring, documenting severity, addressing comorbid disease, and pairing systemic anti-inflammatory therapy with lesion-directed surgery when destructive disease persists.
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Dermatology and oncology

Kaposi Sarcoma

Confirm suspected Kaposi sarcoma with lesional histology and HHV-8 LANA-1 immunohistochemistry, then define HIV status, immunosuppression, and visceral burden to select antiretroviral therapy, immunosuppression reduction, local control, or systemic therapy.
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Dermatology

Melasma

Manage melasma as a chronic, relapsing facial pigment disorder: confirm the clinical pattern, exclude inflammatory, drug-related, and dermal pigment mimics, identify hormonal and photic triggers, and use durable photoprotection with topical therapy before cautiously escalating refractory disease.
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Dermatology

Molluscum Contagiosum

Molluscum contagiosum is usually a clinical diagnosis managed with observation or lesion-directed treatment, but genital disease, atypical morphology, bacterial superinfection, and extensive or refractory lesions require a different diagnostic and immunologic assessment.
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Dermatology

Onychomycosis

Confirm fungal infection before committing patients to prolonged therapy, obtain an adequately proximal subungual specimen, and select topical versus oral treatment by extent, organism, contraindications, interactions, and treatment goals.
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Dermatology

Pemphigus Vulgaris

Confirm pemphigus vulgaris with lesion-directed immunopathology, distinguish it from other blistering disorders and paraneoplastic disease, then use severity and mucosal risk to select systemic corticosteroids, rituximab-based therapy, and steroid-sparing maintenance.
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Dermatology

Psoriasis

Manage psoriasis by confirming the clinical phenotype, quantifying extent and life impact, identifying psoriatic arthritis and cardiometabolic comorbidity, then selecting site-directed topical therapy, phototherapy, systemic therapy, or biologic treatment according to severity, trajectory, and treatment risk.
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Dermatology

Pyoderma Gangrenosum

Pyoderma gangrenosum requires rapid recognition of an inflammatory ulcer pattern while actively excluding infection, vascular disease, vasculitis, and malignancy. Biopsy and cultures should precede immunosuppression when feasible; avoid traumatic debridement once pathergy is suspected.
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Dermatology

Rosacea

Manage rosacea by phenotype rather than a fixed subtype: confirm compatible centrofacial disease, exclude mimics when morphology is atypical, treat inflammatory lesions and persistent erythema separately, and identify ocular or phymatous disease early because corneal injury and tissue remodeling require targeted escalation.
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Dermatology

Scabies

Manage suspected scabies by confirming when uncertainty changes management, treating the patient and close contacts concurrently, distinguishing crusted disease early, and reassessing persistent itch for reinfestation, application failure, dermatitis, or an alternative diagnosis.
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Dermatology

Seborrheic Dermatitis

Manage seborrheic dermatitis clinically when distribution is typical, but perform targeted fungal testing or biopsy for atypical, refractory, or systemic presentations. Use site-directed antifungal therapy for control, brief anti-inflammatory treatment for flares, and maintenance therapy to reduce relapse.
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Dermatology

Seborrheic Keratosis

Seborrheic keratosis is managed conservatively only after a sufficiently confident clinical and dermoscopic assessment. Biopsy lesions with diagnostic uncertainty or atypical features before destructive treatment, because melanoma, basal cell carcinoma, squamous cell carcinoma, and other epidermal tumors can mimic seborrheic keratosis.
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Dermatology

Sunburn

Manage sunburn by identifying blistering or systemic illness that warrants urgent assessment, avoiding further ultraviolet exposure, and using layered photoprotection to prevent recurrent injury. Broad-spectrum sunscreen, protective clothing, and sun avoidance reduce ultraviolet-associated skin damage.
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Dermatology

Telogen Effluvium

Evaluate diffuse shedding by anchoring onset to a trigger, excluding patterned and inflammatory alopecia, and correcting identifiable systemic, nutritional, or medication causes. Acute telogen effluvium usually resolves after trigger removal; shedding beyond 6 months warrants reassessment for chronic disease or a competing diagnosis.
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Dermatology and Pediatrics

Tinea Capitis

Confirm suspected scalp dermatophyte infection with hair and scale microscopy or culture when feasible, begin systemic therapy because topical agents do not reach the follicular infection, identify inflammatory kerion promptly to limit permanent alopecia, and interrupt household transmission with contact assessment and sporicidal shampoo.
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Dermatology

Tinea Corporis

Manage localized tinea corporis with topical antifungal therapy after bedside confirmation when morphology is uncertain; obtain mycologic testing and reassess exposure, adherence, steroid use, and resistance when disease is extensive, recurrent, or treatment-refractory.
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Dermatology

Tinea Cruris

Confirm dermatophyte infection when morphology is atypical, recurrent, extensive, or treatment-refractory; treat limited disease with topical antifungal monotherapy, identify pedal or nail reservoirs, and escalate persistent disease to culture, speciation, susceptibility testing, and systemic therapy planning.
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Dermatology

Tinea Pedis

Confirm atypical, chronic, or treatment-refractory foot eruptions with potassium hydroxide examination, then match topical therapy duration to interdigital versus hyperkeratotic disease. Escalate persistent disease by reassessing diagnosis, nail reservoir, adherence, immunologic risk, bacterial superinfection, and need for culture-directed evaluation.
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Dermatology

Vitiligo

Confirm true depigmentation, define nonsegmental versus segmental distribution and activity, screen selectively for autoimmune disease, and match topical, phototherapy, systemic, or surgical treatment to extent, site, progression, and stability.
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