From the Guidelines
Diagnosing conditions of the epidermis typically involves a combination of visual examination, medical history review, and sometimes laboratory testing, with a skin biopsy being necessary for definitive diagnosis in many cases. A dermatologist will first perform a thorough visual inspection of the affected skin area, noting any abnormalities in color, texture, or appearance, as outlined in the guidelines for managing Stevens-Johnson syndrome/toxic epidermal necrolysis 1. They may use a dermatoscope, a special magnifying tool, to examine skin lesions more closely. In many cases, a skin biopsy is necessary for definitive diagnosis, which involves removing a small sample of skin tissue for microscopic examination, as recommended in the international expert recommendations on image acquisition for in vivo reflectance confocal microscopy of cutaneous tumors 1. This procedure can identify cellular abnormalities, infections, or inflammatory processes.
Some key steps in diagnosing epidermal conditions include:
- Performing a full physical examination, recording baseline body weight, and measuring oxygen saturation with a pulse oximeter, as suggested in the guidelines for managing Stevens-Johnson syndrome/toxic epidermal necrolysis 1
- Looking for target lesions, purpuric macules, blisters, and areas of epidermal detachment, and examining all mucosal sites for mucositis, blisters, and erosions 1
- Recording the extent of erythema and the extent of epidermal detachment separately on a body map, and estimating the percentage of body surface area involved using the Lund and Browder chart 1
- Using in vivo reflectance confocal microscopy to acquire a basic image set, including standard mosaics and stacks, and additional captures based on suspected diagnosis, as recommended in the international expert recommendations 1
Blood tests may also be ordered to check for systemic conditions that manifest on the skin, such as full blood count, erythrocyte sedimentation rate, C-reactive protein, and liver function tests, as suggested in the guidelines for managing Stevens-Johnson syndrome/toxic epidermal necrolysis 1. For fungal infections, skin scrapings can be examined under a microscope or cultured. Patch testing helps identify allergic contact dermatitis by exposing small areas of skin to potential allergens. Wood's lamp examination, which uses ultraviolet light, can help diagnose certain infections and pigmentation disorders. These diagnostic approaches help dermatologists accurately identify various epidermal conditions ranging from common issues like eczema and psoriasis to more serious concerns such as skin cancers.
From the Research
Diagnosis of Epidermal Conditions
The diagnosis of epidermal conditions, such as atopic dermatitis, can be based on symptoms and physical examination findings, as outlined by the American Academy of Dermatology 2. The diagnosis may involve the identification of intensely pruritic skin lesions, which can be triggered by a self-perpetuating itch-scratch cycle.
Diagnostic Criteria
The diagnostic criteria for atopic dermatitis include:
- Symptoms such as intense itch and recurrent eczematous lesions
- Physical examination findings, such as erythematous skin lesions and impairment of epidermal barrier function 3
- A fluctuating course, with periods of remission and exacerbation
Diagnostic Tools
Diagnostic tools, such as bronchoscopic examination, may be used to evaluate the extent of epidermal damage and to guide treatment decisions 4. In some cases, skin biopsies or other diagnostic tests may be necessary to confirm the diagnosis and to rule out other conditions.
Limitations of Current Evidence
There is limited evidence on the specific diagnosis of the epidermis itself, as most studies focus on the diagnosis and treatment of epidermal conditions, such as atopic dermatitis and psoriasis 5, 6. Further research is needed to develop more effective diagnostic tools and treatments for epidermal conditions.