Dermatologic Physical Examination

The four components of the dermatologic physical examination are (1) primary lesions, (2) secondary lesions, (3) distribution, and (4) configuration. Because primary and secondary lesions are rather constant with most dermatitides, they should be relied on heavily to lead to the correct diagnosis. The two other basic components of the physical exam, distribution and configuration, are used for support and confirmation. Some skin disorders lack a distinct distribution or configuration. Occasionally, however, these latter components can be so characteristic for certain diseases that they are by themselves diagnostic. When the distribution and configuration are confusing or fail to support a diagnosis, it is wise to rely most heavily on the information and clues from the primary and secondary lesions.

Learn to internalize what you are observing. It is easy to look at a skin rash but not really see it. Look for and think about each of the distinguishing characteristics of the lesion.

Develop skills in:

1. Recognizing primary lesions.

2. Recognizing secondary lesions.

3. Recognizing distribution.

4. Recognizing configuration.

5. Diagnostic aids.

CLINICAL APPLICATION QUESTIONS

You are asked to evaluate a 60-year-old female patient who is obtunded and cannot give a history. Widespread skin lesions are present; however, family members are not helpful as to the onset or evolution of the lesions.

1. Why do you need to be able to distinguish the various types of primary skin lesions from secondary skin lesions?

2. What is a secondary skin lesion, and how does it assist your diagnostic process?

3. You notice that although there are scattered lesions elsewhere, the patient's eruption is concentrated on the palms and dorsum of the hands, dorsal wrists, and distal dorsal forearms. Why is this information useful for assisting a diagnosis?

4. Scattered lesions on this patient's palms and dorsal hands show an iris configuration. How can this information help you to make a diagnosis?

From: Current Clinical Practice: Dermatology Skills for Primary Care: An Illustrated Guide D.J. Trozak, D.J. Tennenhouse, and J.J. Russell © Humana Press, Totowa, NJ

APPLICATION GUIDELINES

Recognizing Primary Lesions

The earliest constant recognizable lesions in a skin disease are called the primary lesions. Although some dermatitides have primary lesions that are transient and rarely seen, in most conditions the primary lesion is an important clue to the correct diagnosis. Types of primary lesions include the following:

Macule: A circumscribed alteration in skin color, 1 cm or less in size, without any elevation or depression in relation to the adjacent skin (see Figs. 1,2; Photos 1,2).

Patch: A circumscribed alteration in skin color greater than 1 cm in size, without any elevation or depression in relation to the adjacent skin (see Figs. 3,4; Photos 3,4).

Papule: A solid lesion elevated above the adjacent skin less than 1 cm in diameter (see Figs. 5,6; Photos 5,6).

Nodule: A palpable solid lesion usually greater than 1 cm in diameter, which may or may not be elevated above the level of the adjacent skin (see Figs. 7,8; Photos 7,8). The term nodule implies a lesion with depth. The term tumor is sometimes used to denote a large nodule. Because of the associated implication of malignancy we will avoid its usage here.

Plaque: An elevation, solid and fixed, above the level of the adjacent skin. The diameter is large in relation to its degree of elevation. Plaques may have a smooth surface or, if they arise from a confluence of papules, the surface may be pebbly (see Figs. 9,10; Photos 9,10).

Vesicle: A circumscribed fluid-filled lesion less than 0.5 cm in diameter, usually elevated above the level of the adjacent skin. Vesicles may be intraepider-mal or subepidermal (see Fig. 11; Photo 11).

Bulla: A circumscribed fluid-filled lesion greater than 0.5 cm in diameter elevated above the level of the adjacent skin. Bullae may be intraepidermal or subepidermal (see Fig. 11; Photo 11).

Pustule: A circumscribed fluid-filled lesion usually less than 0.5 cm in diameter in which the fluid consists of purulent exudate. Pustules may or may not be elevated. Pustules may be intraepidermal or adnexal in location. Adnexal pustules are those that occur within the ostium of an adnexal skin structure such as a hair follicle or sweat gland (see Figs. 12,13; Photos 12,13).

In certain skin disorders, some of the preceding primary lesions may occur as a late event, superimposed on otherwise characteristic primary lesions; for example, vesicles and bullae may occur as a secondary event on the characteristic primary plaque lesions in urticaria. Primary and secondary lesions are not always mutually exclusive.

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Macule Illustration

ACTUAL LESION IN EPIDERMIS

Figure 1: Macule

ACTUAL LESION IN EPIDERMIS

Figure 1: Macule

VISIBLE PATCH

VISIBLE PATCH

Dermatology Physical Exam Template
Figure 3: Patch
Papule Dermiche
Figure 5: Papule

VISIBLE NODULE COMPOSED OF EPIDERMIS

VISIBLE NODULE COMPOSED OF EPIDERMIS

Dermatology Physical Exam Template
Figure 7: Nodule

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VISIBLE MACULE

VISIBLE MACULE

Figure 2: Macule

VISIBLE PATCH

VISIBLE PATCH

Dermatology Physical Exam Template
Figure 4: Patch

PAPULE

PAPULE

Macules Papules Drawing
Figure 6: Papule

VISIBLE NODULE

VISIBLE NODULE

Pustule Bulla
Figure 8: Nodule
Dermatology Physical Exam TemplateNodule Dermatology
Figure 11: Vesicle/Bulla
Physical Examination
Figure 12: Intra-epidermal pustule Figure 13: Adnexal pustules

Recognizing Secondary Lesions

Secondary lesions are those that develop as the disease process matures. These secondary lesions may evolve from and replace the primary lesion (e.g., a vesicle may be replaced by crust and scale) or, in other instances, the secondary changes may occur while the primary lesions remain. Under certain conditions, lesions normally considered as primary may in fact be secondary lesions. For example, a group of vesicles become pustular when secondarily infected.

Types of secondary lesions include the following:

Scale: The normal maturation process of the epidermis is called ortho keratinization. Small fragments of the outer stratum corneum are continually shed into the environment in an unnoticed fashion. A scale is a grossly visible piece or plate of stratum corneum; the presence of scale signals an alteration of the process of epidermal maturation. The character of the scale usually offers a clue to the correct diagnosis.

1. White or brown adherent scale: An adherent scale is usually a sign of hyperkeratosis, which is a microscopic change in the epidermis indicating excessive maturation and retention of the stratum corneum. Hyperkeratosis is typically seen in certain disorders such as dominant ichthyosis, lichen planus, and discoid lupus erythematosus (see Photos 14,15).

2. Silvery loosely adherent scale: This distinctly white or silvery scale occurs in disorders with enhanced epidermal turnover, where the upper layers of skin show a disordered, incomplete maturation. This process is termed parakerato-sis when viewed under the microscope. The silvery snow-white color is due to air spaces between the loose, poorly stacked cells of the upper epidermis. This type of scale is seen in many skin conditions but is especially characteristic of psoriasis (see Photo 16).

3. Seborrheic scale: This yellow, greasy, loose scale is most often associated with seborrheic dermatitis and microscopically shows changes of parakeratosis similar to silver scale. The altered color and consistency are due to heavy sebum secretion; one could draw an analogy to light flakes of pie crust soaked with cooking oil (see Photo 17).

Erosion: A moist circular or oval shallow depression caused by loss of the epidermis. Erosions heal without scar formation and often occur at the base of vesicles, bullae, and pustules. This secondary change is very common with impetigo and cutaneous monilia (see Fig. 14; Photo 18).

Necrosis: Literally, this means "a condition of death." In the gross sense, it refers to death of parts or portions of skin lesions, not total death of the whole.

Crust: An accumulation of exudate and/or blood (see Fig. 15; Photo 19).

Impetiginization: A superficial honey-colored or purulent exudate. Usually a sign of superficial infection, this change is a characteristic finding in cases of bacterial impetigo. It is seen as a secondary change in many other dermatitides (see Photo 20).

Sclerosis:

Excoriations:

Fissures:

Papillomatosis:

Hypertrichosis:

Hypotrichosis:

Lichenification:

An alteration in the dermis due to an abnormal accumulation of fluid, connective tissue, or metabolite. This change is best recognized by palpating the affected skin between the thumb and forefinger. The dermis has an inelastic feel, which varies from doughy to rock-hard consistency. Normal surface wrinkling during palpation is reduced or absent. Surface changes that suggest an area of sclerosis include white macule, white patch or white plaque formation, epidermal atrophy, peau d'orange effect, coarse telangiectases, and blotchy hyperpigmentation. Surface change may be entirely absent and sclerosis, which is strictly a dermal process, can be fully appreciated only by touch. Sclerosis is typically seen with morphea and other forms of scleroderma but can also occur in a large number of unrelated skin disorders (see Fig. 16; Photo 21).

A self-excavation usually limited to the epidermis (see Photo 22). Excoriations imply the presence of itching, except in der-matitides with heavy psychosomatic overlay or overt delusions. In the latter instances, such changes are deeper and more destructive.

Cleavages or splits in the epidermis that have occurred spontaneously without trauma. Painful fissures are an indication that the split has exposed the underlying dermis. This event usually occurs in very thick or dry epidermis and suggests altered maturation, poor water holding capacity, or both (see Fig. 17; Photo 23).

A pebbly epidermal surface caused by a tight grouping or confluence of papules. Papillomatosis may be of epidermal origin or due to an infiltrate filling the papillary dermis (see Figs. 18,19; Photos 24,25).

Excessive hair growth. This change may be generalized or focal. When generalized it suggests a metabolic alteration of the dermis. When focal it is often associated with a focal lesion, scar, or alteration in dermal vasculature.

Diminished hair growth. This change may be generalized or focal. When generalized it suggests a metabolic alteration of the dermis or widespread fibrosis. When focal it is often associated with a focal lesion or scar. Manipulation of hair can produce breakage or premature epilation, which simulates hypotrichosis.

An epidermal thickening with a surface pattern of accentuated skin lines. Lichenification is caused by chronic repeated low-grade rubbing or scratching and implies the presence of severe pruritus or dysesthesia. It is characteristically, but not exclusively, found in cases of atopic dermatitis (see Photo 22).

Smooth Pruritic Skin Lesions

Figure 14: Erosion

Crusta Dermatologie

Figure 15: Crust

Figure 14: Erosion

Figure 15: Crust

Eschar From Extravasation

Figure 16: Sclerosis

Lichen Sclerosus And Vitiligo

Figure 17: Fissure

Figure 16: Sclerosis

Figure 17: Fissure

Breast Papillomatosis

Figure 18: Papillomatosis

Skin Necrosis Extravasation

Figure 19: Papillomatosis

Figure 18: Papillomatosis

Figure 19: Papillomatosis

Vegetation: A surface alteration caused by tightly packed projections or elevations forming papillary masses. Vegetations may be dry and scaly, soft and smooth, or moist, depending on the underlying cause (see Fig. 20; Photo 26).

Eschar: An area of crust and tissue necrosis that will heal with residual scarring (see Fig. 21; Photo 27).

Purpura: Discoloration of skin ranging from bright red to deep dusky purple, which is due to extravasation of red blood cells into the skin. Purpura does not blanch with pressure (see description diascopy in Diagnostic Aids section).

Atrophy: Loss of tissue by resorption or compression.

1. Epidermal atrophy: There is thinning limited to the epidermis, which imparts to the skin surface a translucent, shiny, ironed-out appearance. When the skin is gently pinched between the examiner's fingers, fine, closely aligned wrinkles appear, much like those one would see stretching a cigarette paper (see Fig. 22; Photos 4,7,23).

2. Dermal atrophy: When limited to the fibrous dermis, this secondary change may or may not be visible. The change is felt by the examiner's finger as a soft area surrounded by a ring of dermis (see Fig. 23; Photo 28).

3. Subcutaneous atrophy: Usually seen in conjunction with epidermal and dermal atrophy, this atrophy produces a deep visible depression. Vascular structures are often visible at the base of the lesion through the thinned skin layers (see Fig. 24; Photo 29).

A loss of epidermis and dermis. Skin ulcers always heal with some residual scar formation (see Fig. 25; Photos 30,31).

A permanent alteration of normal tissue—in this instance, skin—as a result of injury or disease. Scar formation in skin implies some degree of injury to the dermis with an alteration of the normal connective tissue, which may result in both dermal and epidermal changes.

Gangrene: A sharply demarcated area of tissue death, which usually involves all three skin layers. There are two types of gangrene:

1. Wet gangrene, usually due to bacterial infection (see Photo 31).

2. Dry gangrene, usually due to some vascular event (see Photo 32).

Hyperpigmentation: Increased color usually due to deposits of melanin pigment.

Hyperpigmentation may be due to enhanced melanin production with storage in the basal epidermis, or to deposits of free melanin or foreign pigment in the dermis following injury or an inflammatory process that disrupts the lower epidermis, releasing basal cell melanin into the dermis (see Figs. 26,27; Photos 33,34).

Hypopigmentation: Diminished but not absent melanization due to impaired pigment transfer or enhanced epidermal turnover (see Fig. 28; Photo 35).

Ulceration: Scar or Cicatrix:

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Revision: 2nd pages

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Figure 20: Vegetation

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Revision: 2nd pages

Discoid Eschar

Figure 21: Eschar

Figure 20: Vegetation

Figure 21: Eschar

Dermal Atrophy Dermatopathology

Figure 22: Epidermal atrophy

Epidermal Atrophy

Figure 23: Dermal atrophy

Figure 22: Epidermal atrophy

Figure 23: Dermal atrophy

Dermal Atrophy

Figure 24: Subcutaneous atrophy

Subcutaneous Atrophy

Figure 25: Ulcer

Figure 24: Subcutaneous atrophy

Figure 25: Ulcer

Corymbiform Skin

Figure 27: Hyperpigmentation

Figure 26: Hyperpigmentation

Figure 27: Hyperpigmentation

VISIBLE HYPOPIGMENTATION

VISIBLE HYPOPIGMENTATION

Leukoderma
Figure 28: Hypopigmentation Figure 29: Leukoderma

Telangectasia:

Leukoderma:

Calcinosis:

Poikiloderma:

Visibly enlarged or dilated small capillaries or slightly larger terminal vessels visible on the skin surface.

Total depigmentation. A change characteristic of, but not limited to, vitiligo (see Fig. 29; Photo 36).

A pathologic condition in which abnormal amounts of calcium are deposited in a tissue where it does not belong—in this instance, areas of damaged skin.

A constellation of secondary features consisting of pigmentary change (hyper, hypo, or both), atrophy, and telangectasia (dilated surface blood vessels). Poikiloderma is a feature of several skin disorders. Its presence, however, directs the dermatologist toward certain specific diagnoses (see Photo 37).

Cutaneous horn A focal area of hyperkeratosis that takes the shape of a minia-(cornu cutaneum): ture horn. These are almost always associated with premalig-nant or malignant lesions.

Recognizing Distribution

Distribution refers to specific anatomic sites of predilection on the body at which a particular eruption tends to occur. Distribution should be considered in two ways.

Microanatomic distribution:

Some skin disorders affect or localize around specific structures, e.g., hair follicles or eccrine or apocrine glands. This can produce specific, recognizable patterns that are diagnostic. Examples are:

Herpes zoster: Follows the course of specific cutaneous sensory nerve trunks; hence a distribution along sensory dermatomes or in the face and scalp, sites that coincide with cranial nerve distribution (see Fig. 30). Hidradenitis supporativa: This is a disease of apocrine gland-bearing hair follicles and is found in body regions where these structures are located, such as axillae, groin,

Blank Figure Outline Drawing Dermatology
Figure 30: Herpes zoster. Example of microanatomic distribution along neural structures.

inframammary, gluteal, and buttock regions. The examiner must always keep these accessory and adnexal structures in mind and determine whether there is a microanatomic distribution of lesions (see Fig. 31).

Macroanatomic Where on the general skin surface is the eruption? Is it on distribution: flexural or on extensor surfaces? Are the lesions grouped around joints or does the rash occur in intertriginous regions? These are important supporting clues to establishing a correct diagnosis.

Apocrine Glands
Figure 31: Hidradentis supporativa. Example of microanatomic distribution in region of apocrine glands.

Recognizing Configuration

Configuration is the external form or arrangement of specific skin lesions. When present, configuration may be diagnostic or may point to a very limited list of diagnostic possibilities.

Annular: Round, like a ring. This is one of the more common configura tions, and the term is incorporated into the name of several diseases (see Photo 38). Other types of annular lesions include the following:

Annular Arciform

Figure 32: Arciform configuration.

Characteristic Lesion Arciform

Figure 33: Polycyclic configuration.

Figure 32: Arciform configuration.

Figure 33: Polycyclic configuration.

Iris:

Serpiginous:

Linear:

Zosteriform:

1. Arciform: Shaped in curves or incomplete circles (see Fig. 32; Photo 39).

2. Polycyclic: Multiple rings or incomplete circles either contained within one another or overlapping. These latter two variations of annular configuration are uncommon and decidedly limit the number of diagnostic possibilities (see Fig. 33; Photo 40).

This configuration alludes to a many-colored lesion of concentric rings, which may show within itself varied surface morphology. A classic example is the target or iris lesion that is pathognomonic of erythema multiforme. When the margins of such a lesion are vesicular it is referred to as the herpes iris of Bateman (see Fig. 34; Photo 41).

This term applies both to the shape of individual lesions and to the way they evolve and multiply. The term means serpentine or snakelike, and can refer to lesions that have the shape or curl of a resting snake. Serpiginous can also refer to a dermatosis where the individual lesions progress by crawling along in a linear pattern (see Fig. 35; Photo 42).

A dermatosis that occurs along a stripe or line. Linear lesions are quite striking because they often extend across physically diverse skin regions. Keep in mind that linear lesions may have skip areas; one should always look distal and proximal to the main lesion to be certain of the full extent of the problem (see Fig. 36; Photo 43).

Refers to the shape or form of a girdle. This is a classic configuration of herpes zoster. Here is an example of how the various elements of the dermatologic physical exam fit together: Grouped (configuration) vesicles (primary lesions) on an

Dermatological Distribution
Figure 34: Iris configuration. Figure 35: Serpiginous configuration.
Apple Jelly Diascopy
Figure 36: Linear configuration.
Example Physical Exam Form
Figure 37: Zosteriform configuration.

urticarial plaque (second primary lesion) following a unilateral, zosteriform pattern (distribution and second configuration) is diagnostic. Many other dermatitides show a zosteriform configuration but other elements of the examination are different (see Fig. 37; Photo 44).

Grouped: This configuration is almost self-explanatory and refers to sim ilar skin lesions that occur in proximity to one another to form a distinct larger entity. Grouping is quite common and must be

Corymbiform LesionCorymbiform

combined with the other elements of the exam so that a diagnostic picture can emerge (see Fig. 38; Photo 45).

Retiform: Shaped like a net, this is an uncommon configuration that, when present, greatly narrows the diagnostic possibilities (see Fig. 39; Photo 46).

Corymbiform: Resembling a cluster of flowers. This configuration is rare, and is characteristic of certain lesions of secondary syphilis. It can also occur occasionally with mosaic types of verrucous warts (see Fig. 40; Photo 47).

Diagnostic Aids

The following are some simple diagnostic aids and tips that are peculiar to the der-matologic examination:

Color examination: In addition to the features noted above, the color of an eruption is often a critical clue.

1. Bright to dusky red color usually indicates enhanced blood flow due to hyperemia or flow through ectatic (dilated) vessels. If intravascular, the color should blanch with diascopy.

2. Dark blue to purple-black color suggests a stagnant low blood flow condition. If the color fails to blanch with diascopy (see later text), consider extravascular deposits such as red blood cells (purpura or hematoma), melanin, graphite, or other pigments free in the tissue.

3. Brown discoloration is caused by melanin or hemosiderin deposits. As melanin is deposited more deeply in the dermis the physics of color contrast, light reflectance, and the absorption of wavelengths change the color from tan to brown to dark brown, then blue to blue-black.

4. White color can signify diminished melanin content or absent melanin, as seen in vitiligo. It may also indicate intense local vasospasm, a metabolic dermal infiltrate, or dermal fibrosis. Melanin disturbances can be distinguished on physical exam using diascopy and Wood's lamp exam. They do not change with diascopy; however, they are usually accentuated by Wood's lamp exam. The white color of vascular spasm, metabolic infiltrates, and fibrosis will disappear with diascopy and are not accentuated with the Wood's lamp (see later text).

5. Intense yellow-white color is usually due to deposits of lipids or altered connective tissue.

6. Yellow to orange color is caused by the presence of bile or carotene.

7. Gray, blue-gray, to black stains are usually due to deeply deposited melanin, heavy metals, graphite, silica, or the metabolites of certain medications (e.g., desipramine)

Magnification: Use of magnification with a simple handheld magnifier during the visual exam serves two purposes. It may reveal features that are not evident with the naked eye, and the act of using the lens often enhances the examiner's concentration.

Lighting: Proper examination of the skin requires a good color-balanced light source that can be moved around the subject and can be positioned to provide side lighting from various angles. Some skin lesions such as actinic keratoses are visible only by this means. In addition, good lighting is important when assessing surface characteristics such as papillomatosis or a subtle depression. We recommend ceiling-mounted tungsten incandescent lights with a 9-inch reflector. These are shielded with a color-balanced, blue-tinted, quartz shell. This allows the light to be used in varied positions and at different distances. Light sources that are dull, glaring, or overly blue or yellow will obscure findings and make the exam more difficult.

Tactile examination:

1. Skin surface temperature by feel gives a clue as to the degree of blood flow. An inflammatory skin condition such as an eczema is red due to vasodilation but is not warm like the marked hyperemia of a cellulitis. Diminished temperature can confirm a clinical impression of local vascular insufficiency or intense vasospasm.

2. Light touch, accomplished by lightly sliding fingertips over the skin surface, will often reveal lesions that are not readily visible. This is especially true of actinic keratosis.

3. Palpation done gently over lesions will reveal subtle changes such as the outlines of a plaque or nodule or an area of dermal atrophy that is not visible on the surface. One can also determine the consistency of a lesion, whether soft, firm, hard, or fluid-filled, or whether it is pulsatile or compressible.

4. Pinching—that is, gently palpating the skin from side to side between the fingers—allows the examiner to assess the condition of the dermis for thickening or sclerosis and at the same time observe the wrinkle pattern on the surface —if accentuated like a stretched cigarette paper, this suggests epidermal atrophy.

5. Stroking the skin surface firmly with either a fingernail or a blunt instrument will reveal features such as the exaggerated triple response of Lewis seen in immediate dermo-graphism or white dermographism, which is characteristic of atopic dermatitis. The same maneuver applied to most lesions of cutaneous mastocytosis elicits a wheal response referred to as Darier's sign.

Diascopy: This simple technique is performed by compressing the skin surface with a glass microscope slide or a clear plastic stent. Most vascular lesions will empty and will partially or totally disappear, while solid or pigmented lesions remain unchanged (see Photos 46,48). This technique can differentiate, for instance, a large venous ectasia on the ear from a developing melanoma. It will distinguish vascular ectasia (intravascular blood) from purpura (extravascular blood) and by subtracting dusky erythema it may reveal dermal hemorrhage that is not otherwise evident. Light pressure over vascular lesions will often reveal arterial pulsations, giving an additional clue as to the true anatomic structure. Diascopy of papular lesions composed of dense granulomatous or lymphoid infiltrates will accentuate the lesions and impart an amber-yellow or so-called "apple jelly" color. This change is seen in granuloma annulare, cutaneous sarcoid, some forms of cutaneous tuberculosis, and certain benign and malignant lymphocytic infiltrates.

Wood's lamp examination:

A long ultraviolet lamp or so-called "black light" has a number of uses and is a helpful clinical screening tool. Inexpensive battery-powered Wood's lights are available.

1. Certain microsporum fungi (canis, audouini, distortum and ferruginium) produce pigments that give a brilliant green fluorescence when exposed to this light. Once a major screening tool for tinea capitis, black-light exam's usefulness has diminished as M. audouini has been replaced by other nonfluorescent species. Favus, an indolent form of tinea capitis caused by T. schoenleinii, gives off a dull gray-green color.

2. Pseudomonas pyocyanea secretes pyocyanin, which emits a yellow-green color, while the organisms of erythrasma emit a porphyrin, which fluoresces a brilliant coral pink. Similar coral-pink fluorescence is seen in some cases of trichomycosis axillaris.

3. Wood's lamp light will also cause a pink-red to orange-red color in urine and fecal samples of some patients with por-phyria cutanea tarda (see Photo 49).

4. Wood's lamp examination is also useful in the evaluation of pigmentary disturbances. It helps to distinguish partial pigment loss (hypopigmentation) from absolute pigment loss (leukoderma) and also helps to delineate the extent of the disturbance. Conditions such as tinea versicolor and pityriasis alba accentuate as lighter areas. Tinea versicolor with scale may also show pale yellow fluorescence. Vitiligo, where there is complete pigment loss, has a stark white appearance.

5. In conditions in which there is hyperpigmentation, Wood's lamp exam helps to locate the depth and extent of the pigment and, to some degree, predicts the relative success of therapy. Melanin in the epidermis or high dermis is accentuated and appears as dark areas. Pigment in the mid- and deep dermis is not accentuated.

Basic Equipment List for Dermatologic Exam

1. A movable tungsten balanced light source so that the skin can be evaluated at various angles.

2. A simple hand lens or magnifying glass.

3. A small caliper for measuring lesions.

4. A glass slide or clear plastic stent for diascopy.

5. A Wood's lamp (inexpensive battery powered models are available and convenient)

ANSWERS TO CLINICAL APPLICATION QUESTIONS

History Review

You are asked to evaluate a 60-year-old female patient who is obtunded and cannot give a history. Widespread skin lesions are present; however, family members are not helpful as to the onset or evolution of the lesions.

1. Why do you need to be able to distinguish the various types of primary skin lesions from secondary skin lesions?

Answer: Examination of this obtunded woman reveals red macules 3 mm to 1 cm in size, erythematous papules, small and large erythematous plaques up to several centimeters in size, and occasional intact vesicles and bullae filled with clear amber fluid. These are primary, not secondary, lesions. The presence of several different types of primary lesions within the same eruption strongly suggests erythema multiforme. Vesiculobullous drug eruptions, pemphigus vulgaris, bullous pemphigoid, and other major blistering disorders may have a similar appearance but rarely show discrete papular lesions. Blistering viral exanthems usually contain vesicles of uniform size. The presence of bullae in this eruption suggests something other than a viral exanthem.

2. What is a secondary skin lesion, and how does it assist your diagnostic process?

Answer: Secondary skin lesions are changes that evolve from a maturing primary lesion. They are the result of varying degrees and types of injury to the skin. If you cannot distinguish secondary from primary lesions, you cannot identify the primary lesions that are usually essential to the diagnosis. In addition, secondary lesions often offer a clue as to the degree of skin damage, which may alter treatment options.

Erosions may be secondary to epidermal damage caused by vesicle and blister formation. Purpura may occur when there is a significant amount of vascular injury. Necrosis and ulceration can follow severe vascular injury. The presence of secondary lesions such as purpura, erosions, necrosis, and ulceration can assist in identifying the degree of injury in erythema multiforme and in supporting the diagnosis.

3. You notice that although there are scattered lesions elsewhere, the patient's eruption is concentrated on the palms and dorsum of the hands, dorsal wrists, and distal dorsal forearms. Why is this information useful for assisting a diagnosis?

Answer: Many skin disorders have a typical pattern of macrodistribution, which may assist in making a diagnosis. In some conditions, the distribution may be pathognomonic. The pattern of distribution in this patient makes a diagnosis of pemphigus and bullous pemphigoid unlikely. They are usually more generalized. The macrodistribution pattern in this patient suggests erythema multiforme.

4. Scattered lesions on this patient's palms and dorsal hands show an iris configuration. How can this information help you to make a diagnosis?

Answer: Some skin disorders have a typical configuration that may assist or confirm the diagnosis. With the other physical findings, the iris configuration in this patient is pathognomonic for erythema multiforme.

How To Deal With Rosacea and Eczema

How To Deal With Rosacea and Eczema

Rosacea and Eczema are two skin conditions that are fairly commonly found throughout the world. Each of them is characterized by different features, and can be both discomfiting as well as result in undesirable appearance features. In a nutshell, theyre problems that many would want to deal with.

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