Dermoscopy in general dermatology

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Main PageDermoscopy in general dermatologyCutaneous B-cell lymphoma
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 Author(s): Sabine Ludwig     ·  Aimilios Lallas
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Description In this chapter we describe the dermoscopyThe examination of [skin lesions] with a 'dermatoscope'. This traditionally consists of a magnifier (typically x10), a non-polarised light source, a transparent plate and a liquid medium between the instrument and the skin, and allows inspection of skin lesions unobstructed by skin surface reflections. Modern dermatoscopes dispense with the use of liquid medium and instead use polarised light to cancel out skin surface reflections. of inflammatory skin diseases
Author(s) Sabine Ludwig · Aimilios Lallas
Responsible author Aimilios Lallas→ send e-mail
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Status update May 14, 2018
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In this chapter we describe the dermoscopy of inflammatory skin diseases

It has the following subchapters:

Lichen planus Sabine Ludwig, Aimilios Lallas
Psoriasis Sabine Ludwig, Aimilios Lallas
Dermatitis Sabine Ludwig, Aimilios Lallas
Pityrisasis rubra pilaris Sabine Ludwig, Aimilios Lallas
Porokeratosis Sabine Ludwig, Aimilios Lallas
Granulomatous skin disease Sabine Ludwig, Aimilios Lallas
Discoid lupus erythematosus Sabine Ludwig, Aimilios Lallas
Rosacea Sabine Ludwig, Aimilios Lallas
Lichen sclerosus and morphea Sabine Ludwig, Aimilios Lallas
Urticaria and urticarial vasculitis Sabine Ludwig, Aimilios Lallas
Pigmented purpuric dermatoses Sabine Ludwig, Aimilios Lallas
Darier's disease Sabine Ludwig, Aimilios Lallas
Mastocytosis Sabine Ludwig, Aimilios Lallas
Vasculitis Sabine Ludwig, Aimilios Lallas
Mycosis fungoides Sabine Ludwig, Aimilios Lallas
Cutaneous B-cell lymphoma Shamir Geller, Ashfaq A. Marghoob
Juvenile xanthogranuloma Shamir Geller, Ashfaq A. Marghoob


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Selection of the optimal equipmentphysical item that can be used to achieve a goal, especially if the item is not consumed in the process

In dermoscopy of skin tumors, the main dermoscopic structuresThis glossary term has not yet been described. result from deposition of pigment at several levels of the skinThis glossary term has not yet been described.. Vascular structuresThis glossary term has not yet been described. and other features are also seen, but they are usually considered less important as compared to pigmented criteriameasure of how well one variable or set of variables predicts an outcome. In contrast, in inflammatory and infectiousThis glossary term has not yet been described. entities the main histopathologic alterations are usually nit associated with pigment, but include cellular infiltrations, vascular structuresThis glossary term has not yet been described. and alterations of the thickness or the anatomy of the epidermis. Therefore, the selection of an equipment that preserves vesselsThis glossary term has not yet been described.morphologyThis glossary term has not yet been described. and enhances their optimal visualization is much more crucial when evaluating skin eruptions than tumors. The “old-fashioned” non-polarized hand-held dermatoscopes require direct contact of the optical lens to the skin surface, which may result in alteration of the morphology, or even disappearance, of the underlying vascular structures. Using for immersionThis glossary term has not yet been described. ultrasound gel instead of liquid offers the possibility of applying less pressure and better preserve the morphology of the vessels. However, this problem was radically solved by the introduction of the second-generation hand-held dermatoscopes, using polarized lightThis glossary term has not yet been described. and not requiring contact to the skin. In addition to eliminating the pressure problem, polarized dermoscopy offers also a better projection of vascular structures and allows the visualisation of white shiny structuresThis glossary term has not yet been described., which are hardly, or not at all, seen with non-polarised light. In consulsion, we strongly advice the use of non-contact polarised dermatoscopes when applying dermoscopy in general dermatology.

Main categories of dermoscopic criteria

In general, each disease is dermoscopically typified by one or two predominant criteria. The most frequent structures seen in inflammatory skin diseases are vessels, scales or crusts and criteria associated to the hair follicle. Therefore, the most important parameters to be evaluated when dermoscopically examining skin eruptions are the following:

MorphologyThis glossary term has not yet been described. of vessels

Several morphologic types of vessels have been described in dermoscopy, including dotted, glomerular, comma-like, hairpin-like, arborizing, linear irregularlinear vessels with multiple bends, corkscrew-like and othersThis glossary term has not yet been described.This glossary term has not yet been described.. Some of these morphologic types have been associated with specific tumors (ex. arborizing vesselsanalytic term is branched vessels; Bright red sharply in focus large or thick diameter vessels dividing into smaller vessels; BCC with basal ell carcinoma or comma vesselslinear curved short vessels dermal nevi with dermal neviThis glossary term has not yet been described.). However, the intra-observer agreement when evaluating the morphologic type of vessels has been assesses as low. Indeed, there is an obvious overlap between some of the previous terms, especially on linear vesselsLinear mildly curved vessels considered irregular when different sizes shapes and curves with a haphazard or random distribution are presented and considered regular when short and fine (thin) linear vessels prevail various diagnoses (linear irregular with arborizing, comma with hairpin etc). For this reason, but also because many of the aforementioned morphologic types of vessels have not been reported to have a diagnostic significance for any inflammatory or infectious skin disease, we propose a simplified categorisation when applying dermoscopy in general dermatology (figure 1)

  1. Dotted vesselstiny pinpoint vessels. This category includes roundish vessels of any size, without discriminating among pinpoint, dotted and globular vessels, which anyhow differ only in the diameter. Quite frequently, dotted vesselstiny pinpoint vessels of different diameter are simultaneouseously present in the same lesion. Dotted vessels can be seen in the majority of the common inflammatory skin diseases. They have been initially described as the dermoscopic hallmark of psoriasisThis glossary term has not yet been described., but later it was shown that many other inflammatory dermatoses dermoscopically display dotted vessels, including dermatitisalso known as eczema is a group of diseases that results in inflammation of the skin. (all types), lichen planusThis glossary term has not yet been described., pityriasis rosea, porokeratosisThis glossary term has not yet been described. et al.
  2. Linear vesselsLinear mildly curved vessels considered irregular when different sizes shapes and curves with a haphazard or random distribution are presented and considered regular when short and fine (thin) linear vessels prevail various diagnoses, not curved and without branches. Linear vessels are very frequently present in sun-damaged skin. They are also seen in lesions of any disease treated with topical steroids for long periods. The most frequent skin disease characterised by linear vessels is rosaceaThis glossary term has not yet been described., which is typified by a specific arrangementThis glossary term has not yet been described. the vessels in polygonslines angulated or polygonal (non-facial skin) (polygonal vessels).
  3. Linear vessels with branches. They are somehow similar to the typical vessels seen in basal cell carcinomais the most common skin cancer, and one of the most common cancers in the United States.[1] While BCC has a very low metastatic risk, this tumor can cause significant disfigurement by invading surrounding tissues. They can be seen in granulomatousThis glossary term has not yet been described. skin diseases (sarcoidosisThis glossary term has not yet been described., tuberculosis) and at the late stage of discoid lupus erythematosusis a chronic skin condition of sores with inflammation and scarring favouring the face, ears, and scalp and at times on other body areas. These lesions develop as a red, inflamed patch with a scaling and crusty appearance. The centre areas may appear lighter in colour with a rim darker than the normal skin..
  4. Linear curved vesselscomma vessels - linear curved short vessels - dermal nevi monomorphous vessels: one type of vessel dominates. They are similar to the so-called comma vessels that are frequently seen in dermal nevi. They can be found in lichen planus, granulomatous disorders and also in mycosis fungoidesThis glossary term has not yet been described.

Distribution of vessels

  1. Regular. This means that the vacslar structures are equally and homogeneously distributed all over the surface of the lesion. This vacslar arrangement typifies psoriasis.
  2. Peripheral. Vascular structures are distributed mainly at the peripheral part of the lesion. This arrangement is frequently seen in lichen planus.
  3. Patchy. The vascular structures are arranged randomly without following any specific pattern. It is also called asymmetric or unspecific distribution. It can be seen in many diseases, such as dermatitis and pityriasis rosea.
  4. In plexus. The vascular structures form a kind of networkThis glossary term has not yet been described.. This arrangement can be seen in psoriasis (dotted vessels) and is also very characteristic of rosacea (linear vessels).

Color of scales

  1. White. This is the most frequent scale colour and can be found in most of the erythematosquamous and papulosquamous skin diseases, such as psoriasis or lichen planus.
  2. Yellow. Yellow crusts are a result of serum extravasation and yellow scales a result of serum mixed with keratin. Yellow crusts and scales represent the dermoscopic hallmark of all types of dermatitis, corresponding histopathologically to the underlying spongiosis.

Distribution of scales

  1. Diffuse. Scales covering all the surfaces of the lesion. It cannot be considered specific of any diagnosisis the identification of the nature and cause of a certain phenomenon. Diagnosis is used in many different disciplines with variations in the use of logic, analytics, and experience to determine "cause and effect". In systems engineering and computer science, it is typically used to determine the causes of symptoms, mitigations, and solutions, since diffuse scales can be seen in several hyperkeratotic dermatoses.
  2. Central. Scales accentuated in the centre of the lesion. Again, this scaling pattern cannot be considered as specific, although it is quite frequently seen in psoriasis.
  3. Peripheral. Scales sparing the center and distributed mainly at the periphery. It is a classic sign of pityriasis rosea, but can also be seen in tinea corporis and other entities.
  4. Patchy. Random and asymmetric distribution of scales. May be seen in several diseases.

Follicular criteria

  1. Follicular plugs. Keratin plugs of white or yellow color filling the follicular openings. It can be found in several diseases, but is considered as the dermoscopic hallmark of early stage discoid lupus erythematous
  2. Perifollicular white halo. A white-colored circle surrounding each hair follicle and/or filling the space between follicles. It might correspond either to perifollicular fibrosis (ex. discoid lupus erythematosus) or to epidermal hyperplasia (ex. hypertrophic lichen planus).
  3. Perifollicular pigmentation. Pigment accentuated around the hair follicles. It can be seen in some alopecias, but also represents the first sign of re-pigmentation in vitiligo.
  4. Follicular depigmentation. Loss of pigment in the hair follicles, as compared to the surrounding skin. It represents an early sign of active vitiligo, but can also be found in other causes of hypopigmentation.

Specific cluesEvidence, in an investigation

Specific clue is considered a feature that, when present is very strongly suggestive of one only diagnosis. Therefore, specific clues are features that can be seen only in one disease and not in any other entity, especially in those included in the differential diagnosis. Specific clues have been suggested for several diseases, but only a few have been investigated in appropriately designed studies that included control groups. Examples of specific clues are the white crossing ines of lichen planus (Wickham striae) and the peripheral keratotic rim of porokeratosis.


Dermoscopic criteria of inflammatory skin diseases.jpg

PsoriasisThis glossary term has not yet been described.

Dotted vessels represent the most frequent dermoscopic feature of Psoriasis, being present in every single psoriatic plaque. Detection of any other morphologic type of vessels excludes the diagnosis of PP.[1] The term “red globulesThis glossary term has not yet been described.” has also been used to describe the same dermoscopic feature. [2] Distinction between dots and globules is based on the diameter of the structure (dots are smaller), and it is important in dermoscopy of melanocyticThis glossary term has not yet been described. tumors. In psoriasis, both terms may be used, since the roundish vascular structures can be of various diameters, although they are usually of similar size within a given lesion. Under higher magnifications (x100-x400), the psoriatic vessels appear as dilated, elongated, and convoluted capillaries.[3] Histopathologically, red dots correspond to the loops of vertically arranged vessels within the elongated dermal papillae.

Important for differential diagnosis, the uniform distribution of the red dots within the lesion represents the dermoscopic hallmark of psoriasis. Dotted vessels may be detected in several inflammatory dermatoses, but no other disease exhibits the symmetrical and homogenous arrangement of vessels all over the lesion that characterizes psoriatic plaques, unless thick superficialThis glossary term has not yet been described. scales cover them.[1] Scales removal will bring to light the characteristic vascular pattern of psoriasis, possibly together with tiny red blood drops, which can be characterized as the dermoscopic “Auspitz sign”. A specific feature for the diagnosis of psoriasis is the sign of red globular rings, described by Vazquez-Lopez et al. If present, the red globules are arranged in irregular circles or rings. But even if highly specific, this sign is only seen in a minority of psoriatic lesions. Other types of vessels distribution are extremely rare in psoriasis.[1][4] In addition, light red background color and white superficial scales are two common dermoscopic criteria of plaque psoriasis. In differential diagnosis of erythematosquamous dermatoses, scale color is of particular value: Yellow scales are a negative predictor of plaque psoriasis, therefore argueing for the presence of dermatitis. [1]

Dermoscopic findings of psoriasis may vary dependent of the body sitedescribes the area of the body and the various amounts of scaling. In psoriatic balanitis and inverse psoriasis lesions that lack scaling, the regularly distributed red dots are prominent. Contrariwise, in scalp or palmoplantar psoriasis, thick hyperkeratotic plaques hide the typical vascular structures, which may be recognized after removal of the scales.[5]

Dermoscopic transformation of psoriatic plaques under treatment

Regular dermoscopic examination is of avail in patients under treatment with topical steroids or systemic biological agents, because additional morphologic information might be helpful for early detection of a relapse. Additionally, steroid-induced skin atrophy is earlier detected by dermoscopy (by revealing characteristic linear vessels) than in the clinical setting.[6]

Dermatitisalso known as eczema is a group of diseases that results in inflammation of the skin.

Despite their variable etiopathologies, all forms of dermatitis show similar histopathologic just as similar dermoscopic characteristics. Dermatitis usually exhibits red dots in a patchy distribution and yellow scales.[1] The red dots are identical to the vessels in psoriatic lesions, but unlike psoriasis, their distribution is not homogenous and regular, but rather clustered, generating an irregular, “patchy” pattern.[1]

SuperficialThis glossary term has not yet been described. scaling is a frequent characteristic of dermatitis, but opposed to psoriasis and other erythematosquamous skin diseases, the scales in dermoscopy of dermatitis reveal a yellow color either alone, or in combinationThis glossary term has not yet been described. with white. [1] Belonging to the group of the characteristic yellow scales, the “yellow clod sign” is frequently observed in nummular eczema.[7] Notably, yellow scale color is dermoscopically detected not only in acute, but also in chronic dermatitis. Contact dermatitis, nummular eczema, generalized dermatitis, chronic dermatitis, seborrheic dermatitis and other subtypes were reported to reveal similar findings in dermoscopy, but further investigation on their specific pattern is needed.[1][8][9]

Lichen planusThis glossary term has not yet been described.

White crossing streakslines radial (always at periphery) streaks Reed nevus melanoma recurrent nevus (Wickham striae) are the hallmark of lichen planus not only in clinical examinationThis glossary term has not yet been described. (particularly in mucous lesions), but also in dermoscopy.[2][10] White crossing streaks are a specific, as well as a constant finding for lichen planus, irrespectively of lesion’s duration or subtype.[11] VesselsThis glossary term has not yet been described. of mixed morphology (dotted and linear) may be found at the periphery of the lesion.

Pityriasis rosea

The two major dermoscopic features of pityriasis rosea are yellowish background color and peripheral whitish scales. Besides, dotted vessels may be detected in dermoscopy of most pytiriasis rosea lesions, as seen in psoriasis and dermatitis. However, the vascular pattern lacks the characteristic regular distribution of psoriasis.[12][13]

Pityriasis rubra pilarisThis glossary term has not yet been described.

Whitish keratotic plugs and linear vessels either solely or mixed with dotted vessels on a yellowish background are the most frequent dermoscopic features reported for pityriasis rubra pilarisThis glossary term has not yet been described..[14] This observation suggests that pityriasis rubra pilaris shows no typical characteristics of psoriasis, which is the most common differential diagnosis. [15][14][16]

PorokeratosisThis glossary term has not yet been described.

In porokeratosis, the cornoid lamella, known as the histopathologic hallmark of porokeratosis, is revealed by dermoscopic examination as a well-defined, white-yellowish peripheral annular structure (“white track”, ‘‘the outlines of a volcanic crater as observed from a high pointThis glossary term has not yet been described.’’).[17][18][19][20]

In disseminated superficial actinic porokeratosis, the peripheral track may be hyperpigmentedThis glossary term has not yet been described..[21][22][23] Depending on the disease subtype and the stage of progression, the central part of porokeratotic lesions can demonstrate a brownish pigmentation, dotted or linear vessels, or a structureless whitish area. By dermoscopy, the diagnosis of porokeratosis is performed without difficulty, even in clinically atypical cases.

GranulomatousThis glossary term has not yet been described. skin diseases

In dermoscopy, the presence of orange-yellowish globules or areas and linear vessels are highly suggestive of dermal granulomas and therefore easily allows the diagnosis of granulomatous skin diseases. However, their differential diagnosis remains challenging due to identical dermoscopic presentationThis glossary term has not yet been described. produced by several causes. Notably, the plaque form of cutaneous sarcoidosis may resemble necrobiosis lipoidica.[24][25] The longer and more branching telangiectasias of necrobiosis lipoidica, caused by atrophic changes not present in cutaneous sarcoidosis, were reported to be an important feature for discrimination from other granulomatous diseases.[26][27]

SarcoidosisThis glossary term has not yet been described. and lupus vulgarisThis glossary term has not yet been described.

In sarcoidosis [24] and lupus vulgaris[28], orange-yellowish translucent globular-like or structureless areas in combination with linear vessels have been described, which are suggested to correspond to the underlying granulomas.

Cutaneous leishmaniasis

In cutaneous leishmaniasis, dermoscopy reveals generalized erythema, yellow tears (follicular plugs), hyperkeratosis and central erosion/ulceration. The characteristic translucent orange-yellowish color of sarcoidosis may additionally be present.[29]

Granuloma annulareThis glossary term has not yet been described.

Granuloma anulare may reveal a high variability of dermoscopic findings. Vessels may be dotted, short linear or linear arborizing, while background color displays various combinations of red, white and yellow. In certain cases, pigmented structures may be detected. The observation that granuloma anulare rarely exhibits features of other granulomatous skin diseases, such as necrobiosis lipoidica or sarcoidosis, might helpRefers to giving assistance or support to others for mutual benefit clinicians rule out the latter conditions.[27]

Necrobiosis lipoidica

Necrobiosis lipoidica exhibits a characteristic and repetitive pattern, typified by a prominent network of linear arborizing vessels and a yellow background colorColor (American English) or colour (Commonwealth English) is the characteristic of human visual perception described through color categories, with names such as red, yellow, purple, or blue.. The prominent vascular network of necrobiosis lipoidica represent the most valuable feature for differential diagnosis from other granulomatous diseases.[30][26] This typical vascular morphology should be differentiated from the classical ‘arborizing' vessels of nodularThis glossary term has not yet been described.-cystic basal cell carcinoma. Classical arborizing vessels usually reveal ramifications into finest capillaries, while vessels in necrobiosis lipoidica exhibit only few diameter variegations and reveal multiple anastomosing ramifications.[27] Ulcerations and yellow crusts represent the most common additional features.[30]

Discoid lupus erythematosusis a chronic skin condition of sores with inflammation and scarring favouring the face, ears, and scalp and at times on other body areas. These lesions develop as a red, inflamed patch with a scaling and crusty appearance. The centre areas may appear lighter in colour with a rim darker than the normal skin.

Dermoscopic criterias differ depending on the stage of progression of discoid lupus erythematosus. In early lesions, perifollicular whitish halo, follicular plugging and white scales are the predominant features, while in longer-standing lesions telangiectatic vessels, pigmentation structures and whitish structureless areas prevail.[31] This distinct dermoscopic pattern is useful for discriminating discoid lupus erythematosus from lupus pernio (cutaneous sarcoidosis) and lupus vulgaris (cutaneous tuberculosis). The latter diseases lack the predominant follicular abnormalities of discoid lupus erythematosus, and display a characteristic pattern consisting of orange-yellowish areas/globules and branching arborizing vessels.[28]

RosaceaThis glossary term has not yet been described.

Rosacea is characterized by a unique dermoscopic vascular pattern of polygonal vessels. Since this pattern of dermoscopic vascular polygons is not present in any other skin disease, this is a sensitive criterion for the diagnosis of rosacea. Regarding the accuracy in evaluation of vascular alterations by dermoscopy, the technique may be additionally useful for follow up of rosacea. Additional dermoscopic findings of rosacea include follicular plugs, white scales, features related to the presence of demodex (“demodex tails”) and whitish amorphic follicular material.[32] However, the frequency of these additional criteria is relatively low.

In papulopustular rosacea, clinically non-visible pustules provide a useful dermoscopic clue for discrimination from lupus erythematosus, but this requires further investigation.

Lichen sclerosus and morphea

The predominant dermoscopic feature of lichen sclerosus are white-yellowish structureless areas, independently of the location. Genital lichen sclerosus commonly appear with linear vessels while extragenital lesions rather exhibit keratotic plugs, surrounded by an erythematous halo. This halo represents a marker of disease activity.[33][34] In morphea, linear vessels within the lilac ring are a typical finding in dermoscopy.[8] By dermoscopical examination, lichen sclerosus is typified by comedo-like openings[[Comedo like openings]] and whitish patches, whereas morphea exhibits fibrotic beams.[35]

Urticaria and urticarial vasculitisThis glossary term has not yet been described.

Common urticaria is dermoscopically characterized by a red, reticular network of linear vessels, which may be surrounded by an area devoid of vessels, corresponding to dermal edema.[36] On the contrary, urticarial vasculitis dermoscopically exhibit purpuric dots or globules on an orange-brown background.[37] Both diseases reveal no highly specific criteria, but the presence of purpuric dots is suggestive of an underlying vasculitis.

Pigmented purpuric dermatoses

The term pigmented purpuric dermatoses comprehends the following entities: Schamberg’s disease, Majocchi purpura, eczematoid purpura of Doucas and Kapetanakis, lichen aureus and pigmented purpuric lichenoid dermatitis of Gougerot-Blum. Pigmented purpuric dermatoses are dermoscopically identified by the combination of purpuric dots or globules and orange-brown areas of pigmentation.[38][39] A similar dermoscopic pattern has been described in patients with mycosis fungoides, supporting previous evidence reporting clinical and histopathologic overlap between the two entities.[9] Since the pigmented purpuric dermatoses and mycosis fungoides notably differ in physical course and managementThis glossary term has not yet been described., lesions showing a dermsocopic pattern of pigmented purpuric dermatoses should be evaluated carefully.

Darieris an autosomal dominant disorder discovered by French dermatologist Ferdinand-Jean Darier. Darier's is characterized by dark crusty patches on the skin, sometimes containing pus. The crusty patches are also known as keratotic papules, keratosis follicularis or dyskeratosis follicularis.[4][5] Mild forms of the disease are the most common, consisting solely of skin rashes that flare up under certain conditions such as high humidity, high stress or tight-fitting clothes. Even in mild forms, short stature combined with poorly formed fingernails containing vertical striations are diagnostic.’s disease

In Darier’s disease, dermoscopical analysis highlights the characteristic pseudocomedones and therefore is an effective additional tool for its clinical recognition. Vascular patternsThis glossary term has not yet been described. are unspecific, comprising erythema, dotted and linear vessels.[40]

MastocytosisThis glossary term has not yet been described.

For cutaneous mastocytosisis a form of mastocytosis that primarily affects the skin. There are three main forms of the condition: maculopapular cutaneous mastocytosis (also called urticaria pigmentosa), solitary cutaneous mastocytoma, and diffuse cutaneous mastocytosis. There is also an exteremely rare form called telangiectasia macularis eruptiva perstans. The signs, symptoms and severity of the condition vary by subtype. four dermoscopic patterns have been defined: light-brown blot, pigment networkGrid-like pattern consisting of interconnecting pigmented lines surrounding hypopigmented holes., reticular vascular pattern, and yellow-orange blot. [41][42] Dermoscopic pattern varies depending on the subtype [42]: In maculopapular mastocytosisThis glossary term has not yet been described., light-brown blot and pigment network predominate. In solitary mastocytoma, a yellow orange blot is typical. In all cases of telangiectasia macularis eruptiva perstans, a reticular vascular pattern is present. The reticular pattern of the vessels is even proved associated with an increased risk of need for daily use of anti-mediator medication. Therefore, dermoscopy in combination with other variables could provide additional help in the identification of patients at risk for more severe symptoms.

Vasculitides

Scarce evidence exists on the dermoscopic pattern of vasculitides. Henoch-Schonlein purpura has been shown to dermoscopically reveal irregularly shaped red patches with blurred borders. Reported findings of urticarial vasculitis are described above.[43]

In granuloma faciale, the specific dermoscopic features are dilated follicular openings, perifollicular whitish halo, follicular keratotic plugs and linear branching vessels. Clinically, granuloma faciale has to be differentiated from sarcoidosis, discoid lupus erythematosus, lupus vulgaris, lymphomaThis glossary term has not yet been described. and basal cell carcinoma. The mentioned dermoscopic patterns simplify clinical differential diagnosis. But the distinction from discoid lupus erythematosus, which exhibits similar findings, remains challenging.[44]

Mycosis fungoidesThis glossary term has not yet been described.

Even if being a neoplastic disease, mycosis fungoides is listed in this article as a major differential diagnosis from several inflammatory skin disorders. In particular, differentiation between chronic dermatitis and early stage mycosis fungoides is often highly problematic. In dermoscopical studies, significant differences have been shown: In contrast to the dotted vessels in dermatitis, mycosis fungoides reveal short linear vessels and orange-yellowish areas. In addition, in mycosis fungoides a peculiar vascular structure is frequently observed consisting of a dotted and a linear component (spermatozoon-like structure). In the assessment of a chronic lesion previously diagnosed as dermatitis, dermoscopic examination is expected to reveal dotted vessels, occasionally combined with yellowish scales. Lesions under long-term treatment with topical steroids represent the only exception to this rule. When, instead, dermoscopy reveals linear vessels, the suspicion of mycosis fungoides rises strongly and in this case, patient’s management should be adjusted accordingly.[9]

ReferencesThis is material contained in a footnote or bibliography holding further information.
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  25. Bakos et al.: DermatoscopyThe examination of [skin lesions] with a 'dermatoscope'. This traditionally consists of a magnifier (typically x10), a non-polarised light source, a transparent plate and a liquid medium between the instrument and the skin, and allows inspection of skin lesions unobstructed by skin surface reflections. Modern dermatoscopes dispense with the use of liquid medium and instead use polarised light to cancel out skin surface reflections. of early-onset necrobiosis lipoidica. J. Am. Acad. Dermatol. 2012;66:e143-4. PMID: 22421129. DOI.
  26. 26.026.1 Balestri et al.: Dermoscopic subpatterns of granulomatous skin diseases. J. Am. Acad. Dermatol. 2013;69:e217-8. PMID: 24124838. DOI.
  27. 27.027.127.2 Pellicano et al.: Dermoscopy of necrobiosis lipoidica and granuloma annulareThis glossary term has not yet been described.. Dermatology (Basel) 2013;226:319-23. PMID: 23797090. DOI.
  28. 28.028.1 Brasiello et al.: Lupus vulgarisThis glossary term has not yet been described.: a new look at an old symptom--the lupoma observed with dermoscopy. Dermatology (Basel) 2009;218:172-4. PMID: 19060460. DOI.
  29. Llambrich et al.: Dermoscopy of cutaneous leishmaniasis. Br. J. Dermatol. 2009;160:756-61. PMID: 19120331. DOI.
  30. 30.030.1 Bakos et al.: Dermatoscopy of early-onset necrobiosis lipoidica. J. Am. Acad. Dermatol. 2012;66:e143-4. PMID: 22421129. DOI.
  31. Lallas et al.: Dermoscopy of discoid lupus erythematosus. Br. J. Dermatol. 2013;168:284-8. PMID: 22985425. DOI.
  32. Segal et al.: Dermoscopy as a diagnostic tool in demodicidosisThis glossary term has not yet been described.. Int. J. Dermatol. 2010;49:1018-23. PMID: 20931672.
  33. Larre Borges et al.: Clinical, dermoscopic and histopathologic features of genital and extragenital lichen sclerosus. J Eur Acad Dermatol Venereol 2013;27:1433-9. PMID: 22646723. DOI.
  34. Garrido-Ríos et al.: Dermoscopy of extragenital lichen sclerosus. Arch Dermatol 2009;145:1468. PMID: 20026867. DOI.
  35. Shim et al.: Diagnostic usefulness of dermatoscopy in differentiating lichen sclerous et atrophicus from morphea. J. Am. Acad. Dermatol. 2012;66:690-1. PMID: 22421117. DOI.
  36. Vázquez-López et al.: Dermoscopy for the screening of common urticaria and urticaria vasculitisThis glossary term has not yet been described.. Arch Dermatol 2008;144:568. PMID: 18427065. DOI.
  37. Vázquez-López et al.: Surface microscopy for discriminating between common urticaria and urticarial vasculitis. Rheumatology (Oxford) 2003;42:1079-82. PMID: 12730524. DOI.
  38. Zaballos et al.: Dermoscopy of pigmented purpuric dermatoses (lichen aureus): a useful tool for clinical diagnosis. Arch Dermatol 2004;140:1290-1. PMID: 15492206. DOI.
  39. Zalaudek et al.: [Atypical clinical presentation of pigmented purpuric dermatosis]. J Dtsch Dermatol Ges 2006;4:138-40. PMID: 16503941. DOI.
  40. Vázquez-López et al.: The handheld dermoscope improves the recognition of giant pseudocomedones in Darier's diseaseis an autosomal dominant disorder discovered by French dermatologist Ferdinand-Jean Darier. Darier's is characterized by dark crusty patches on the skin, sometimes containing pus. The crusty patches are also known as keratotic papules, keratosis follicularis or dyskeratosis follicularis.[4][5] Mild forms of the disease are the most common, consisting solely of skin rashes that flare up under certain conditions such as high humidity, high stress or tight-fitting clothes. Even in mild forms, short stature combined with poorly formed fingernails containing vertical striations are diagnostic.. J. Am. Acad. Dermatol. 2004;50:454-5. PMID: 14988691. DOI.
  41. Akay et al.: Dermatoscopic findings of cutaneous mastocytosis. Dermatology (Basel) 2009;218:226-30. PMID: 19060465. DOI.
  42. 42.042.1 Vano-Galvan et al.: Dermoscopic features of skin lesions in patients with mastocytosis. Arch Dermatol 2011;147:932-40. PMID: 21844452. DOI.
  43. Ohnishi et al.: Angioma serpiginosumis a skin condition in which there are small blood vessels near the skin surface. It presents as small red dots (puncta) that cluster together to form a linear or snake-like array (serpiginous pattern) or ring-shaped (gyrate) pattern.: a report of 2 cases identified using epiluminescence microscopy. Arch Dermatol 1999;135:1366-8. PMID: 10566835.
  44. Lallas et al.: Photoletter to the editor: Dermoscopy of granuloma faciale. J Dermatol Case Rep 2012;6:59-60. PMID: 22826723. DOI.