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Secondary Skin Lesions

The identification Identification Defense Mechanisms and classification of a patient's skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions lesions are important steps in the diagnosis of any skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions disorder. Primary lesions represent the initial presentation Presentation The position or orientation of the fetus at near term or during obstetric labor, determined by its relation to the spine of the mother and the birth canal. The normal position is a vertical, cephalic presentation with the fetal vertex flexed on the neck. Normal and Abnormal Labor of the disease process. Secondary lesions develop from irritated or manipulated primary lesions and/or manifestations of disease progression. The key features of skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions lesions include type, morphology, color, shape, arrangement, and distribution. A comprehensive examination of the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions, appendages, and mucous membranes is done, with the type of procedure performed depending on the suspected diagnosis.

Last updated: 14 Mar, 2022

Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

Scales

Scales are dry or greasy masses of keratin Keratin A class of fibrous proteins or scleroproteins that represents the principal constituent of epidermis; hair; nails; horny tissues, and the organic matrix of tooth enamel. Two major conformational groups have been characterized, alpha-keratin, whose peptide backbone forms a coiled-coil alpha helical structure consisting of type I keratin and a type II keratin, and beta-keratin, whose backbone forms a zigzag or pleated sheet structure. Alpha-keratins have been classified into at least 20 subtypes. In addition multiple isoforms of subtypes have been found which may be due to gene duplication. Seborrheic Keratosis that represent thickened stratum corneum Stratum corneum Skin: Structure and Functions.

Characteristic types of scales are:

  • Silvery-white scales: psoriasis Psoriasis Psoriasis is a common T-cell-mediated inflammatory skin condition. The etiology is unknown, but is thought to be due to genetic inheritance and environmental triggers. There are 4 major subtypes, with the most common form being chronic plaque psoriasis. Psoriasis
  • Greasy/waxy, yellowish scales: seborrheic dermatitis Seborrheic dermatitis Seborrheic dermatitis is a common chronic, relapsing skin disorder that presents as erythematous plaques with greasy, yellow scales in susceptible areas (scalp, face, and trunk). Seborrheic dermatitis has a biphasic incidence, occurring in two peaks: first in infants, then in adolescence and early adulthood. Seborrheic Dermatitis
  • Dry, diffuse, and fish FISH A type of in situ hybridization in which target sequences are stained with fluorescent dye so their location and size can be determined using fluorescence microscopy. This staining is sufficiently distinct that the hybridization signal can be seen both in metaphase spreads and in interphase nuclei. Chromosome Testing-like scales on lower legs (ichthyosiform): ichthyosis vulgaris Ichthyosis Vulgaris Ichthyosis vulgaris is the most common type of keratinization disorders. The condition occurs due to an autosomal dominant mutation in the filaggrin gene, which results in skin-barrier dysfunction. Ichthyosis Vulgaris
  • Fine scales: tinea versicolor Tinea versicolor A common chronic, noninflammatory and usually symptomless disorder, characterized by the occurrence of multiple macular patches of all sizes and shapes, and varying in pigmentation from fawn-colored to brown. It is seen most frequently in hot, humid, tropical regions and is mostly caused by Malassezia furfur (formerly Pityrosporum orbiculare). Malassezia Fungi
  • Scaling in sheets: scarlet fever Scarlet fever Infection with group a Streptococci that is characterized by tonsillitis and pharyngitis. An erythematous rash is commonly present. Scarlet Fever
  • Follicular scales (such as keratotic plugs): keratosis pilaris Keratosis Pilaris Ichthyosis Vulgaris
  • Gritty (sandpaper-like) scales: actinic keratosis Actinic keratosis Actinic keratosis (AK) is a precancerous skin lesion that affects sun-exposed areas. The condition presents as small, non-tender macules/papules with a characteristic sandpaper-like texture that can become erythematous scaly plaques. Actinic Keratosis
Lizard skin appearance of ichthyosis

Thickened, “lizard skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions” appearance of ichthyosis vulgaris Ichthyosis Vulgaris Ichthyosis vulgaris is the most common type of keratinization disorders. The condition occurs due to an autosomal dominant mutation in the filaggrin gene, which results in skin-barrier dysfunction. Ichthyosis Vulgaris

Image: “In vivo confocal microscopy of pre-Descemet corneal dystrophy associated with X-linked ichthyosis X-linked ichthyosis Chronic form of ichthyosis that is inherited as a seX-linked recessive trait carried on the x-chromosome and transmitted to the male offspring. It is characterized by severe scaling, especially on the extremities, and is associated with steroid sulfatase deficiency. Ichthyosis Vulgaris: a case report” by BMC Ophthalmology. License: CC BY 4.0

Crust

  • Dried exudate Exudate Exudates are fluids, cells, or other cellular substances that are slowly discharged from blood vessels usually from inflamed tissues. Pleural Effusion of body fluids (blood, pus, or sebum Sebum The oily substance secreted by sebaceous glands. It is composed of keratin, fat, and cellular debris. Infectious Folliculitis) on an area of damaged skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions
  • The color of the crust gives clues to its cause:
    • Yellow crusts arise from sebum Sebum The oily substance secreted by sebaceous glands. It is composed of keratin, fat, and cellular debris. Infectious Folliculitis.
    • Yellow-green crusts are formed from pus.
    • Red or brown crusts are formed from blood (hemorrhagic crust).
  • Shape may indicate previous lesion:
  • May be thin, delicate, and easy to remove or thick and deeply attached to the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions.
  • Examples include:
    • Tinea capitis Tinea capitis Ringworm of the scalp and associated hair mainly caused by species of Microsporum; Trichophyton; and Epidermophyton, which may occasionally involve the eyebrows and eyelashes. Dermatophytes/Tinea Infections
    • Impetigo Impetigo Impetigo is a highly contagious superficial bacterial infection typically caused by Staphylococcus aureus (most common) and Streptococcus pyogenes. Impetigo most commonly presents in children aged 2 to 5 years with lesions that evolve from papules to vesicles to pustules, which eventually break down to form characteristic “honey-colored” crusts. Impetigo
    • Scabs on healing wounds
Crusted, nonbullous impetigo on the upper extremity of a pediatric patient

Crusted, nonbullous impetigo Impetigo Impetigo is a highly contagious superficial bacterial infection typically caused by Staphylococcus aureus (most common) and Streptococcus pyogenes. Impetigo most commonly presents in children aged 2 to 5 years with lesions that evolve from papules to vesicles to pustules, which eventually break down to form characteristic “honey-colored” crusts. Impetigo on the upper extremity of a pediatric patient

Image: “Diagnosis of Atopic Dermatitis Atopic Dermatitis Atopic dermatitis, also known as eczema, is a chronic, relapsing, pruritic, inflammatory skin disease that occurs more frequently in children, although adults can also be affected. The condition is often associated with elevated serum levels of IgE and a personal or family history of atopy. Skin dryness, erythema, oozing, crusting, and lichenification are present. Atopic Dermatitis (Eczema): Mimics, Overlaps, and Complications” by Siegfried EC, Hebert AA AA Amyloidosis. License: CC BY 4.0

Erosion

  • Discontinuity of the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions exhibiting incomplete loss of the epidermis Epidermis The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of epithelium: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis). Skin: Structure and Functions
  • Does not penetrate below the dermal–epidermal junction Dermal–Epidermal Junction Bullous Pemphigoid and Pemphigus Vulgaris and, thus, heals without scarring Scarring Inflammation
  • Lesion is moist, well-circumscribed, and depressed.
  • Can be traumatic, inflammatory, or due to infectious Infectious Febrile Infant skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions diseases
  • Examples include: 
    • Tinea pedis Tinea pedis Dermatological pruritic lesion in the feet, caused by Trichophyton rubrum, T. mentagrophytes, or Epidermophyton floccosum. Dermatophytes/Tinea Infections
    • Candidiasis Candidiasis Candida is a genus of dimorphic, opportunistic fungi. Candida albicans is part of the normal human flora and is the most common cause of candidiasis. The clinical presentation varies and can include localized mucocutaneous infections (e.g., oropharyngeal, esophageal, intertriginous, and vulvovaginal candidiasis) and invasive disease (e.g., candidemia, intraabdominal abscess, pericarditis, and meningitis). Candida/Candidiasis
    • Eczematous disease
    • Herpes simplex Herpes Simplex A group of acute infections caused by herpes simplex virus type 1 or type 2 that is characterized by the development of one or more small fluid-filled vesicles with a raised erythematous base on the skin or mucous membrane. It occurs as a primary infection or recurs due to a reactivation of a latent infection. Congenital TORCH Infections
Punched-out erosions with cutaneous herpes simplex virus infection

Punched-out erosions Erosions Corneal Abrasions, Erosion, and Ulcers with cutaneous herpes simplex Herpes Simplex A group of acute infections caused by herpes simplex virus type 1 or type 2 that is characterized by the development of one or more small fluid-filled vesicles with a raised erythematous base on the skin or mucous membrane. It occurs as a primary infection or recurs due to a reactivation of a latent infection. Congenital TORCH Infections virus Virus Viruses are infectious, obligate intracellular parasites composed of a nucleic acid core surrounded by a protein capsid. Viruses can be either naked (non-enveloped) or enveloped. The classification of viruses is complex and based on many factors, including type and structure of the nucleoid and capsid, the presence of an envelope, the replication cycle, and the host range. Virology infection

Image: “Disseminated cutaneous Herpes Simplex Herpes Simplex A group of acute infections caused by herpes simplex virus type 1 or type 2 that is characterized by the development of one or more small fluid-filled vesicles with a raised erythematous base on the skin or mucous membrane. It occurs as a primary infection or recurs due to a reactivation of a latent infection. Congenital TORCH Infections Virus Virus Viruses are infectious, obligate intracellular parasites composed of a nucleic acid core surrounded by a protein capsid. Viruses can be either naked (non-enveloped) or enveloped. The classification of viruses is complex and based on many factors, including type and structure of the nucleoid and capsid, the presence of an envelope, the replication cycle, and the host range. Virology-1 in a woman with rheumatoid arthritis Arthritis Acute or chronic inflammation of joints. Osteoarthritis receiving infliximab Infliximab A chimeric monoclonal antibody to tnf-alpha that is used in the treatment of rheumatoid arthritis; ankylosing spondylitis; psoriatic arthritis and Crohn’s disease. Disease-Modifying Antirheumatic Drugs (DMARDs): a case report” by Justice Justice An interactive process whereby members of a community are concerned for the equality and rights of all. Research Ethics EA, Khan SY, Logan S, Jobanputra P. License: CC BY 2.0

Excoriation

Excoriation Excoriation Mastitis is a linear abrasion Abrasion Soft Tissue Abscess produced by mechanical means (scratching, rubbing, or picking) that usually involves only the epidermis Epidermis The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of epithelium: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis). Skin: Structure and Functions but can reach the papillary dermis Dermis A layer of vascularized connective tissue underneath the epidermis. The surface of the dermis contains innervated papillae. Embedded in or beneath the dermis are sweat glands; hair follicles; and sebaceous glands. Skin: Structure and Functions.

Excoriation disorder secondary to skin picking

Excoriation Excoriation Mastitis disorder secondary to skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions picking

Image: “Derma me” by Boogafreak/Vatadoshu. License: Public Domain

Ulcer

  • A breakdown of the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions exhibiting complete loss of the epidermis Epidermis The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of epithelium: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis). Skin: Structure and Functions and often portions of the dermis Dermis A layer of vascularized connective tissue underneath the epidermis. The surface of the dermis contains innervated papillae. Embedded in or beneath the dermis are sweat glands; hair follicles; and sebaceous glands. Skin: Structure and Functions and subcutaneous fat Subcutaneous fat Fatty tissue under the skin throughout the body. Erythema Nodosum
  • Ulcers always result in a scar Scar Dermatologic Examination.
  • Causes include:
    • Trauma (e.g., heat Heat Inflammation, cold, electrical, chemical)
    • Infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease (e.g., bacterial, viral, fungal)
    • Chronic venous stasis
    • Vascular compromise (e.g., decubitus ulcers and peripheral arterial disease)
Ulcer from chronic venous stasis

Ulcer from chronic venous stasis

Image: “Interaction between a regenerative matrix and wound bed in nonhealing ulcers: results with 16 cases” by Motolese A, Vignati F, Brambilla R, Cerati M, Passi A. License: CC BY 3.0

Fissure

  • A linear crack Crack The purified, alkaloidal, extra-potent form of cocaine. It is smoked (free-based), injected intravenously, and orally ingested. Use of crack results in alterations in function of the cardiovascular system, the autonomic nervous system, the central nervous system, and the gastrointestinal system. The slang term ‘crack’ was derived from the crackling sound made upon igniting of this form of cocaine for smoking. Cocaine Use Disorder in the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions that is usually narrow and extends through the epidermis Epidermis The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of epithelium: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis). Skin: Structure and Functions into the dermis Dermis A layer of vascularized connective tissue underneath the epidermis. The surface of the dermis contains innervated papillae. Embedded in or beneath the dermis are sweat glands; hair follicles; and sebaceous glands. Skin: Structure and Functions
  • Caused by external tension or excessive drying of the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions
  • Fissures commonly occur at the angles of the mouth (angular cheilitis Cheilitis Inflammation of the lips. It is of various etiologies and degrees of pathology. Oral Cancer).
  • Examples also include eczema Eczema Atopic dermatitis, also known as eczema, is a chronic, relapsing, pruritic, inflammatory skin disease that occurs more frequently in children, although adults can also be affected. The condition is often associated with elevated serum levels of IgE and a personal or family history of atopy. Skin dryness, erythema, oozing, crusting, and lichenification are present. Atopic Dermatitis (Eczema) (fingertips) and intertrigo.
Hand eczema with fissure

Hand Hand The hand constitutes the distal part of the upper limb and provides the fine, precise movements needed in activities of daily living. It consists of 5 metacarpal bones and 14 phalanges, as well as numerous muscles innervated by the median and ulnar nerves. Hand: Anatomy eczema Eczema Atopic dermatitis, also known as eczema, is a chronic, relapsing, pruritic, inflammatory skin disease that occurs more frequently in children, although adults can also be affected. The condition is often associated with elevated serum levels of IgE and a personal or family history of atopy. Skin dryness, erythema, oozing, crusting, and lichenification are present. Atopic Dermatitis (Eczema) with fissure Fissure A crack or split that extends into the dermis Generalized and Localized Rashes

Image: “Occupational protein contact dermatitis Contact dermatitis A type of acute or chronic skin reaction in which sensitivity is manifested by reactivity to materials or substances coming in contact with the skin. It may involve allergic or non-allergic mechanisms. Male Genitourinary Examination: two case reports” by Rocha J, Pereira T, Sousa-Basto A, Brito C. License: CC BY 3.0

Atrophy

  • A loss of tissue that can be epidermal, dermal, or subcutaneous
  • Atrophic skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions usually appears thin, translucent, and wrinkled.
  • Produced by long-term sun exposure Exposure ABCDE Assessment, aging, and some inflammatory and neoplastic skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions diseases, such as systemic lupus erythematosus Systemic lupus erythematosus Systemic lupus erythematosus (SLE) is a chronic autoimmune, inflammatory condition that causes immune-complex deposition in organs, resulting in systemic manifestations. Women, particularly those of African American descent, are more commonly affected. Systemic Lupus Erythematosus and cutaneous T-cell lymphoma Lymphoma A general term for various neoplastic diseases of the lymphoid tissue. Imaging of the Mediastinum
  • Atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation also may occur as a result of the long-term use of topical corticosteroids Corticosteroids Chorioretinitis.
Atrophic skin of the left hip seen in granulomatous slack skin

Atrophic skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions of the left hip seen in granulomatous slack skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions (T-cell lymphoma Lymphoma A general term for various neoplastic diseases of the lymphoid tissue. Imaging of the Mediastinum)

Image: “Granulomatous slack skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions T-cell lymphoma Lymphoma A general term for various neoplastic diseases of the lymphoid tissue. Imaging of the Mediastinum: an important differential diagnosis with giant cell tumor Tumor Inflammation of soft tissue Soft Tissue Soft Tissue Abscess” by Adriano AR AR Aortic regurgitation (AR) is a cardiac condition characterized by the backflow of blood from the aorta to the left ventricle during diastole. Aortic regurgitation is associated with an abnormal aortic valve and/or aortic root stemming from multiple causes, commonly rheumatic heart disease as well as congenital and degenerative valvular disorders. Aortic Regurgitation, Lima TS, Battistella M, Bagot M. License: CC BY 4.0, cropped by Lecturio.

Lichenification

  • Thickening and hyperpigmentation Hyperpigmentation Excessive pigmentation of the skin, usually as a result of increased epidermal or dermal melanin pigmentation, hypermelanosis. Hyperpigmentation can be localized or generalized. The condition may arise from exposure to light, chemicals or other substances, or from a primary metabolic imbalance. Malassezia Fungi of the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions resulting from repeated rubbing
  • Normal skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions/skinfold markings become more prominent.
  • Examples include:
    • Lichen simplex chronicus Lichen Simplex Chronicus A benign vulvar skin disorder characterized by hyperkeratosis (thickening of the skin) that occurs secondary to chronic vulvar irritation Benign Vulvar Conditions
    • Prurigo
    • Atopic dermatitis Atopic Dermatitis Atopic dermatitis, also known as eczema, is a chronic, relapsing, pruritic, inflammatory skin disease that occurs more frequently in children, although adults can also be affected. The condition is often associated with elevated serum levels of IgE and a personal or family history of atopy. Skin dryness, erythema, oozing, crusting, and lichenification are present. Atopic Dermatitis (Eczema)

Approach to Diagnosing Skin Conditions

Complete medical history

  • Underlying conditions (e.g., autoimmune disorders, diabetes Diabetes Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus)
  • Accompanying symptoms (e.g., burning, itching)
  • Medications
  • Allergies Allergies A medical specialty concerned with the hypersensitivity of the individual to foreign substances and protection from the resultant infection or disorder. Selective IgA Deficiency
  • Evolution and duration of skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions lesion, aggravating and alleviating factors
  • Social, sexual, and travel history

Physical examination

A general physical examination as well as a focused dermatologic examination Dermatologic examination Examination of the skin is a fundamental part of the standard physical exam. This exam consists of a thorough inspection of the skin of the entire body. The assessment focuses on identifying abnormal signs on the skin, such as the scalp, orifices, nails, and mucosal surfaces. Dermatologic Examination should be performed:

  • Skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions and its appendages as well as mucous membranes
  • Performed with the naked eye and using a dermatoscope

Skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions features and commonly associated skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions conditions and/or lesions to consider:

  • Texture Texture Dermatologic Examination
  • Morphology: 
  • Diameter: varies per condition
  • Composition: fluid-filled, pus-filled, blood-filled, or solid
  • Borders: regular Regular Insulin or irregular, flat or raised
  • Color: hypopigmentation Hypopigmentation A condition caused by a deficiency or a loss of melanin pigmentation in the epidermis, also known as hypomelanosis. Hypopigmentation can be localized or generalized, and may result from genetic defects, trauma, inflammation, or infections. Malassezia Fungi, hyperpigmentation Hyperpigmentation Excessive pigmentation of the skin, usually as a result of increased epidermal or dermal melanin pigmentation, hypermelanosis. Hyperpigmentation can be localized or generalized. The condition may arise from exposure to light, chemicals or other substances, or from a primary metabolic imbalance. Malassezia Fungi, or erythema Erythema Redness of the skin produced by congestion of the capillaries. This condition may result from a variety of disease processes. Chalazion
  • Arrangement: grouped (herpetiform)/scattered
  • Configuration: 
    • Annular Annular Dermatologic Examination: tinea corporis Tinea corporis Dermatophytes/Tinea Infections, granuloma annulare
    • Round/discoid/nummular: eczema Eczema Atopic dermatitis, also known as eczema, is a chronic, relapsing, pruritic, inflammatory skin disease that occurs more frequently in children, although adults can also be affected. The condition is often associated with elevated serum levels of IgE and a personal or family history of atopy. Skin dryness, erythema, oozing, crusting, and lichenification are present. Atopic Dermatitis (Eczema), discoid lupus
    • Polycyclic: urticaria Urticaria Urticaria is raised, well-circumscribed areas (wheals) of edema (swelling) and erythema (redness) involving the dermis and epidermis with associated pruritus (itch). Urticaria is not a single disease but rather is a reaction pattern representing cutaneous mast cell degranulation. Urticaria (Hives)
    • Arcuate: urticaria Urticaria Urticaria is raised, well-circumscribed areas (wheals) of edema (swelling) and erythema (redness) involving the dermis and epidermis with associated pruritus (itch). Urticaria is not a single disease but rather is a reaction pattern representing cutaneous mast cell degranulation. Urticaria (Hives)
    • Linear: scabies Scabies Scabies is an infestation of the skin by the Sarcoptes scabiei mite, which presents most commonly with intense pruritus, characteristic linear burrows, and erythematous papules, particularly in the interdigital folds and the flexor aspects of the wrists. Scabies burrow, lichen nitidus
    • Reticular: livedo reticularis Livedo reticularis A condition characterized by a reticular or fishnet pattern on the skin of lower extremities and other parts of the body. This red and blue pattern is due to deoxygenated blood in unstable dermal blood vessels. The condition is intensified by cold exposure and relieved by rewarming. Chronic Kidney Disease
    • Serpiginous: cutaneous larva migrans Cutaneous Larva Migrans Hookworm Infections
    • Targetoid lesions: erythema Erythema Redness of the skin produced by congestion of the capillaries. This condition may result from a variety of disease processes. Chalazion multiforme
    • Whorled: incontinentia pigmenti
Secondary skin lesions

Secondary skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions lesions:
Erosion Erosion Partial-thickness loss of the epidermis Generalized and Localized Rashes: discontinuity of the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions with incomplete loss of the epidermis Epidermis The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of epithelium: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis). Skin: Structure and Functions without penetration Penetration X-rays below the dermal–epidermal junction Dermal–Epidermal Junction Bullous Pemphigoid and Pemphigus Vulgaris
Ulcer: complete loss of the epidermis Epidermis The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of epithelium: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis). Skin: Structure and Functions and portions of the dermis Dermis A layer of vascularized connective tissue underneath the epidermis. The surface of the dermis contains innervated papillae. Embedded in or beneath the dermis are sweat glands; hair follicles; and sebaceous glands. Skin: Structure and Functions and subcutaneous fat Subcutaneous fat Fatty tissue under the skin throughout the body. Erythema Nodosum resulting in a scar Scar Dermatologic Examination
Fissure Fissure A crack or split that extends into the dermis Generalized and Localized Rashes: narrow linear crack Crack The purified, alkaloidal, extra-potent form of cocaine. It is smoked (free-based), injected intravenously, and orally ingested. Use of crack results in alterations in function of the cardiovascular system, the autonomic nervous system, the central nervous system, and the gastrointestinal system. The slang term ‘crack’ was derived from the crackling sound made upon igniting of this form of cocaine for smoking. Cocaine Use Disorder/split in the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions, extending through the epidermis Epidermis The external, nonvascular layer of the skin. It is made up, from within outward, of five layers of epithelium: (1) basal layer (stratum basale epidermidis); (2) spinous layer (stratum spinosum epidermidis); (3) granular layer (stratum granulosum epidermidis); (4) clear layer (stratum lucidum epidermidis); and (5) horny layer (stratum corneum epidermidis). Skin: Structure and Functions into the dermis Dermis A layer of vascularized connective tissue underneath the epidermis. The surface of the dermis contains innervated papillae. Embedded in or beneath the dermis are sweat glands; hair follicles; and sebaceous glands. Skin: Structure and Functions
Atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation: loss of tissue that can be epidermal, dermal, or subcutaneous with appearance of thin, translucent, and/or wrinkled skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions surface
Excoriation Excoriation Mastitis: linear abrasion Abrasion Soft Tissue Abscess produced by mechanical means (scratching, rubbing, or picking)
Crust: dried exudate Exudate Exudates are fluids, cells, or other cellular substances that are slowly discharged from blood vessels usually from inflamed tissues. Pleural Effusion of body fluids (blood, pus, or sebum Sebum The oily substance secreted by sebaceous glands. It is composed of keratin, fat, and cellular debris. Infectious Folliculitis) on an area of damaged skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions
Scale Scale Dermatologic Examination: dry or greasy masses of keratin Keratin A class of fibrous proteins or scleroproteins that represents the principal constituent of epidermis; hair; nails; horny tissues, and the organic matrix of tooth enamel. Two major conformational groups have been characterized, alpha-keratin, whose peptide backbone forms a coiled-coil alpha helical structure consisting of type I keratin and a type II keratin, and beta-keratin, whose backbone forms a zigzag or pleated sheet structure. Alpha-keratins have been classified into at least 20 subtypes. In addition multiple isoforms of subtypes have been found which may be due to gene duplication. Seborrheic Keratosis representing thickened stratum corneum Stratum corneum Skin: Structure and Functions
Lichenification Lichenification Atopic Dermatitis (Eczema): thickening and hyperpigmentation Hyperpigmentation Excessive pigmentation of the skin, usually as a result of increased epidermal or dermal melanin pigmentation, hypermelanosis. Hyperpigmentation can be localized or generalized. The condition may arise from exposure to light, chemicals or other substances, or from a primary metabolic imbalance. Malassezia Fungi of the skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions resulting from repeated rubbing

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Diagnostic procedures

  • Skin Skin The skin, also referred to as the integumentary system, is the largest organ of the body. The skin is primarily composed of the epidermis (outer layer) and dermis (deep layer). The epidermis is primarily composed of keratinocytes that undergo rapid turnover, while the dermis contains dense layers of connective tissue. Skin: Structure and Functions biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma (lesion excised, saucerized, or taken by punch biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma)
  • KOH preparation KOH preparation Primary Skin Lesions
    • Lesion is scraped and placed on a glass microscope slide, where it is treated with 1 or 2 drops of a solution of 10%–20% KOH.
    • If fungal infection suspected
  • Tzanck smear Tzanck smear Herpes Simplex Virus 1 and 2: cytologic technique when vesicular conditions are noted ( infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease from herpes simplex Herpes Simplex A group of acute infections caused by herpes simplex virus type 1 or type 2 that is characterized by the development of one or more small fluid-filled vesicles with a raised erythematous base on the skin or mucous membrane. It occurs as a primary infection or recurs due to a reactivation of a latent infection. Congenital TORCH Infections virus Virus Viruses are infectious, obligate intracellular parasites composed of a nucleic acid core surrounded by a protein capsid. Viruses can be either naked (non-enveloped) or enveloped. The classification of viruses is complex and based on many factors, including type and structure of the nucleoid and capsid, the presence of an envelope, the replication cycle, and the host range. Virology or varicella zoster virus Virus Viruses are infectious, obligate intracellular parasites composed of a nucleic acid core surrounded by a protein capsid. Viruses can be either naked (non-enveloped) or enveloped. The classification of viruses is complex and based on many factors, including type and structure of the nucleoid and capsid, the presence of an envelope, the replication cycle, and the host range. Virology).
  • Diascopy Diascopy Primary Skin Lesions: determines whether lesion will blanch under pressure, differentiating a hemorrhagic (does not blanch) from a fluid-filled lesion
  • Wood’s light: 
    • Uses 360-nm UV light UV light That portion of the electromagnetic spectrum immediately below the visible range and extending into the x-ray frequencies. The longer wavelengths (near-uv or biotic or vital rays) are necessary for the endogenous synthesis of vitamin D and are also called antirachitic rays; the shorter, ionizing wavelengths (far-uv or abiotic or extravital rays) are viricidal, bactericidal, mutagenic, and carcinogenic and are used as disinfectants. Bullous Pemphigoid and Pemphigus Vulgaris to evaluate lesions
    • Conditions: erythrasma (coral pink color), Pseudomonas Pseudomonas Pseudomonas is a non-lactose-fermenting, gram-negative bacillus that produces pyocyanin, which gives it a characteristic blue-green color. Pseudomonas is found ubiquitously in the environment, as well as in moist reservoirs, such as hospital sinks and respiratory equipment. Pseudomonas wound infection (blue), vitiligo Vitiligo Vitiligo is the most common depigmenting disorder and is caused by the destruction of melanocytes. Patients present with hypo- or depigmented macules or patches which often occur on the face, hands, knees, and/or genitalia. Vitiligo (white)
  • Patch test Patch Test Primary Skin Lesions: allergens placed on patient’s back under occlusive dressings and then checked for hypersensitivity reactions after 48 hours

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References

  1. Amerson, E. H., Burgin, S., Shinkai, K. (2019). Fundamentals of clinical dermatology: morphology and special clinical considerations. In Kang, S., et al. (Eds.). Fitzpatrick’s Dermatology, 9th ed. McGraw-Hill.
  2. Bolognia, J. L., Schaffer, J.V ., Cerroni, L. (2018). Basic Principles of Dermatology, 4th ed. Edinburgh. Elsevier.

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