Difference between revisions of "Inflammatory skin disorders"

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==Pyoderma gangrenosum==
==Pyoderma gangrenosum==
===General===
{{Main|Pyoderma gangrenosum}}
*May be seen in [[IBD]] (UC and CD) - approximately 30% of cases.<ref name=pmid16858047/>
 
Clinical
*''[[Pathergy]]'' = minor trauma (to the skin) results in a non-healing lesion.<ref name=pmid22202507>{{Cite journal  | last1 = Wong | first1 = WW. | last2 = Machado | first2 = GR. | last3 = Hill | first3 = ME. | title = Pyoderma gangrenosum: the great pretender and a challenging diagnosis. | journal = J Cutan Med Surg | volume = 15 | issue = 6 | pages = 322-8 | month =  | year =  | doi =  | PMID = 22202507 }}</ref>
 
===Gross===
*Skin ulceration - classically on the legs.<ref name=pmid16858047>{{Cite journal  | last1 = Brooklyn | first1 = T. | last2 = Dunnill | first2 = G. | last3 = Probert | first3 = C. | title = Diagnosis and treatment of pyoderma gangrenosum. | journal = BMJ | volume = 333 | issue = 7560 | pages = 181-4 | month = Jul | year = 2006 | doi = 10.1136/bmj.333.7560.181 | PMID = 16858047 | PMC = 1513476 | URL = http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1513476/?tool=pubmed }}</ref>
 
===Microscopic===
Features:<ref name=pmid16858047/>
*Early: lymphocytes cells only in the dermis - often perivascular & vascular.
**+/-Fibrinoid necrosis of vessels at edge of lesion.
*Late: abscess formation ([[neutrophil]]s).
 
DDx:
*[[Vasculitis]].
*[[Sweet syndrome]].
 
====Image====
*[http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1513476/figure/fig5/ Pyoderma gangrenosum (nih.gov)].
 
===Sign out===
<pre>
A. Skin, Left Leg from Central Wound, Punch Biopsy:
- Necrotic debris with underlying granulation tissue and benign connective tissue
  with superficial vasculitis, see comment.
- NEGATIVE for skin surface.
 
B. Skin, Left Leg from Wound and Normal Skin Junction, Punch Biopsy:
- Skin with ulceration, necrotic debris, and superficial vasculitis, see comment.
- Fat necrosis and severe atherosclerosis.
 
Comment:
The findings are in keeping with pyoderma gangrenosum; however, atherosclerotic disease
and vasculitis should be considered clinically. 
 
The vasculitis is seen superficially and is likely secondary to the ulceration.
</pre>


==Necrobiotic xanthogranuloma==
==Necrobiotic xanthogranuloma==

Revision as of 20:12, 19 October 2015

Inflammatory skin disorders, also inflammatory skin diseases, are a significant part of dermatopathology. They lead to trepidation among pathologists that don't see lots of skin. Non-inflammatory skin disease is covered in dermatologic neoplasms and non-malignant skin disease.

Classification

  • Bullous.
  • Interface.
  • Nodular & diffuse.
  • Spongiotic.
  • Vasculitis.
  • Perivascular.
  • Panniculitis.
  • Psoriasiform.

Tabular comparison of inflammatory skin disease (adapted from Brinster[1][2]):

Pattern Key histologic feature Subclassifications Example Image
Bullous large "empty spaces" -subcorneal
-suprabasillar
-subepidermal
-pemphigus foliaceus
-pemphigus vulgaris
-dermatitis herpetiformis
PV (WC)
Interface inflammation at DE junction -vacuolar (minimal)
-lichenoid (band-like)
-erythema multiforme, SLE
-lichen planus
VID (WC)
Nodular & diffuse intradermal inflammatory infiltrate - nodular and/or diffuse -neutrophic
-lymphocytic
-plasmic
-eosinophilic
-histocytic
-follicular occlusion triad, ruptured cyst/follicle
-CTCL, reactive
-plasma cell neoplasm, syphilis
-eosinophilic cellulitis, Kimura disease
-granuloma annulare, sarcoidosis, TB
CTCL (WC)
Spongiotic small empty spaces between keratinocytes - can see squamous bridges (best seen at high power); +/- quasi-microvacuolar appearance -acute
-subacute
-chronic
-poison ivy
-nummular dermatitis
-atopic dermatitis
severe (WC), mild (WC)
Vasculitis inflammation of vessel wall/vessel was destruction -small vessel
-medium vessel
-large vessel
-leukocytoclastic vasculitis
-PAN
-giant cell arteritis
CCS (WC)
Perivascular inflammation around vessels -neutrophilic
-lymphocytic
-mastocytic
-eosinophilic
-cellulitis
-viral exanthem, Rx reaction
-mastocytosis
-insect bite, Rx reaction
DPLI (WC)
Panniculitis inflammation of adipose tissue -septal
-lobular
-erythema nodosum, scleroderma panniculitis
-erythema induratum, infection
Psoriasiform epidermal thickening
and long rete ridges
-regular
-irregular
-psoriasis
-lichen simplex chronicus
LSC (WC)

Notes:

  • DE junction = dermal-epidermal junction.
  • The "empty space" in bullous disease in situ is filled with fluid.

Non-specific patterns

Psoriasiform pattern

General

  • Can be subclassified.

DDx:

  • Psoriasis vulgaris (most common).
  • Psoriatic arthritis.
  • Drug-induced.
  • Dermatomycosis (fungal infection).
  • Others.

Microscopic

Features:[3][1]

  • Regular epidermal thickening - as very long rete ridges (described as "test tube-morphology") - key feature.
    • Epidermis between rete ridges thin ("thinning of suprapapillary plate").
  • Parakeratosis.
  • Thin/absent granular layer.
  • Dilated blood vessels in superficial dermis.
  • Neutrophil clusters (Munro microabscess).

Specific diseases

Seborrheic dermatitis

General

  • Very common.

Microscopic

Features:[4]

  • Spongiosis (epidermal edema).
  • Acanthosis (epidermal thickening).
  • "Follicular lipping" = parakeratosis with neutrophils.
  • Perivascular neutrophils and lymphocytes.

Lupus erythematosus

General

Microscopic

Features - classic:

  • Lymphocytic interface dermatitis.[5]
  • Basal layer vacuolization.[6]
  • Intradermal mucin.
  • Thin epidermis.
  • Compact stratum corneum.

DDx:

Images

Discoid lupus erythematosus

General

Microscopic

Features:[7]

  • Lymphocytic interface dermatitis with basal layer vacuolation and keratinocyte apoptosis.
  • Deep dermal lymphocytes.
  • Basket weave stratum corneum.
  • Dermal mucin.
  • Thick dermal-epidermal basement membrane.

DDx:

Image:

Dermatomyositis

For the muscle manifestations see: Neuromuscular_pathology#Dermatomyositis.

General

  • Complement mediated disease - membrane attack complex.
  • Usually middle age.
  • Associated skin rash is common.
    • May precede or follow muscle pathology.
  • Associated with malignancy in approximately 10% of cases.[8]

Clinical:

  • Jo-1 +ve.

Gross

  • Have lesions on the knuckles - Gottron's papules.

Microsopic

Features:

  • Vacuolar interface dermatitis (lymphocytic inflammation at the dermal-epidermal junction).
  • +/-Loss of rete ridges.

DDx:

  • Lupus.

Lichen planus

Should not be confused with lichen planus-like keratosis.
  • Abbreviated LP.

General

Etiology:

  • Autoimmune disease, T-cell–mediated.[11]

Clinical:[12]

  • 6 Ps: pruritic (itchy), purple, polygonal, planar papules and plaques.

Note:

  • Clinically, lichen planus and lichen sclerosus are similar. The main difference is lichen planus involves mucous membranes.[13]

Gross

  • Wickham striae = white lines/dots.
    • Due to hypergranulosis.

Microscopic

Features:[14][15]

  • Loss of basal cells (stratum basale) -- key feature.
  • Loss of rete ridges/formation of pointed rete ridges "sawtoothing".
  • Interface dermatitis (lymphocytes at dermal-epidermal junction).
  • Hypergranulosis; stratum granulosum thickened (grossly seen as "Wickham stria" = white lines).
  • Hyperkeratosis; stratum corneum thickened.
  • Necrotic basal cell in dermis = colloid bodies = Civatte bodies.[16]
    • Pink bodies approximately the size of a keratinocyte.

Notes:

DDx:

Images

Stains

  • PAS-D or PAS-F to exclude a fungal infection.

Sign out

FORESKIN, CIRCUMCISION:
- LICHEN PLANUS.
VULVA, LEFT POSTERIOR FOURCHETTE, BIOPSY:
- COMPATIBLE WITH LICHEN PLANUS.

Micro

The sections show skin with a lymphoplasmacytic interface dermatitis, basal cell loss, hypergranulosis, hyperkeratosis, loss of the rete ridges and Civatte bodies.

The epidermis matures to the surface. No significant nuclear atypia is identified.

Fungal organisms are not identified with a PAS-D stain.

Lichen sclerosus

Microscopic

Features:[19]

  • Subepithelial fibrosis - key feature.

Psoriasis

General

  • Other considerations:
    • Drug-induced psoriasis.[22]

Clinical

  • Auspitz sign = pin-point bleeding on removal of scale.
  • Koebner phenomenon = lesions form at site of trauma.

Common locations:[20]

  • Knees, elbows, scalp, glands penis.

Microscopic

Features:[20]

  • "Regular" acanthosis + long rete ridges (psoriasiform hyperplasia).
  • Parakeratosis.
  • Dilated vessels in superficial dermis (give rise to Auspitz sign).
  • Spongiform pustules = PMNs in stratum spinosum.
  • PMNs in parakeratotic stratum corneum (Munro microabscess).
  • Thinning of the suprapapillary plate.
    • The epidermis between rete ridges is thinner than in the normal adjacent skin - key feature.

DDx:

Note:

Images

www:

Stains

Sign out

SKIN LESION, LEFT ARM, PUNCH BIOPSY:
- SKIN WITH ACANTHOSIS, HYPERKERATOSIS, FOCAL PARAKERATOSIS, PROMINENT
  DILATED VESSELS IN THE SUPERFICIAL DERMIS, SUPERFICIAL SPONGIFORM PUSTULES.
- MILD NONSPECIFIC PERIVASCULAR INFLAMMATION.
- NEGATIVE FOR FUNGAL ORGANISMS WITH PAS STAINING.

COMMENT:
The findings are compatible with psoriasis.  

Micro

The sections show skin with regular psoriasiform change, hyperkeratosis, focal parakeratosis, prominent dilated vessels in the superficial dermis, superficial clusters of intraepidermal neutrophils (spongiform pustules) and thinning of the suprapapillary plate is present. A few perivascular inflammatory cells are present.

There is no epidermal necrosis. Eosinophils are not apparent. The lymphocytes do not have significant atypia.

Lichen striatus

General

Features:[24]

  • Benign, self-limited.

Clinical:

Clinical image:

Microscopic

Features:

  • "Ball and glove" pattern:
    • Rete ridges (glove) surround nexts of lymphocytes (ball).
  • Hyperkeratosis.
  • Parakeratosis.

DDx:

Images:

Lichen aureus

General

  • Rare.

Clinical:[25]

  • Plaques + minimal scale - erythematous/golden.

Microscopic

Features:[25]

  • Lymphocyte-predominant perivascular pattern.
    • May have features suggestive of vacuolar interface pattern.
  • Fibrosis of superficial papillary dermis.

Images:

Granuloma faciale

General

Microscopic

Features:[27]

  • Neutrophilic vasculitis - often subtle:
    • Neutrophils within blood vessel walls.
    • Vessels destruction (fibrinoid necrosis or nuclear dust).
  • Mixed inflammatory superficial dermal infiltrate.
    • Eosinophils, neutrophils, plasma cells, histiocytes.
  • Lesion separated from the (normal) epidermis (Grenz zone).[26]

DDx of chronic fibrosing leukocytoclastic vasculitis:[27]

  • Granuloma faciale.
  • Erythema elevatum diutinum - lacks Grenz zone.
  • Inflammatory pseudotumour.

Image:

Atopic dermatitis

  • AKA atopic eczema, AKA infantile eczema.

General

  • Very common - especially in children.[28]
    • Most children outgrow the condition.

Microscopic

Features:

  • Spongiotic dermatitis.

DDx:

Images

Sweet syndrome

General

  • Uncommon.

Microscopic

Features:

  • Nodular and diffuse pattern - neutrophils predominant - without pus.

DDx rips:

  • Rheumatoid neutrophilic dermatitis.
  • Bowel-associated dermatosis-arthritis syndrome.
  • Pyoderma gangrenosum.
  • Sweet syndrome.

Image:

Granuloma inguinale

Not to be confused with granuloma annulare.
  • Previously known as donovanosis.

General

  • Infection caused by Klebsiella granulomatis - Gram-negative, rod-shaped bacteria.
    • Used to be known as Calymmatobacterium granulomatis.[30]

Location:

Clinical:[31]

  • Sexually transmitted.
  • Nodule or papule developing into a painless ulcer in the inguinal region.
  • No lymphadenopathy (unlike syphilis).

Microscopic

Features:

  • Donovan bodies - key feature:
    • Rod-shaped bodies within histiocytes.

DDx:

Image:

Stains

Pyoderma gangrenosum

Necrobiotic xanthogranuloma

  • Abbreviated NXG.

General

  • Usually elderly.[32]

Gross

Features:

  • Periorbital - classic location.[33]

Microscopic

Features:[32]

  • "Necrobiotic granuloma":
    • Palisading granuloma with a core collagen-like material.
  • +/-Cholesterol clefts - common.
  • +/-Touton giant cells.
  • +/-Atypical foreign body-type giant cells +/- asteroid bodies.

DDx:

Image:

DDx for pattern

Spongiotic dermatitides

DDx:[1]

Psoriasiform dermatitides

Regular psoriasiform dermatitis

DDx:[1]

Irregular psoriasiform dermatitis

Interface dermatitides

Vacuolar interface dermatitides

DDx:[1]

Others:[1]

Additional:[34]

  • Phototoxic dermatitis.
  • Acute radiation dermatitis.
  • Erythema multiforme-like drug eruption.
  • Lichen sclerosis et atrophicus.
  • Erythema dyschromicum perstans (ashy dermatosis).

Super lame mnemonic Danny G & SLE:

  • Dermatomyositis, GVHD, SLE, Lichen sclerosus, Erythema multiforme.

Lichenoid interface dermatitides

DDx:[1]

Additional:[34]

Bullous disease

Subcorneal bullous disorders

DDx with acantholysis:[1]

DDx without acantholysis:DDx:[1]

Suprabasilar bullous disorders

DDx:[1]

Memory device - PhD + Grover = Pemphigus vulgaris, Hailey-Hailey, Darier, Grover.

Subepidermal bullous disorders

DDx:[1]

Others:

Mnemonic DELPHI:

  • Dermatitis herpetiformis.
  • Epidermolysis bullosa acquisita.
  • Bullous lupus erythematosis.
  • Pemphigoid, bullous.
  • Herpes gestationis - rare autoimmune bullous dermatosis of pregnancy, not related to HSV.[35]
  • Linear IgA disease.

Dermatitides with perivascular inflammation

Lymphocytes

Lymphocytes (tightly cuffed):[1]

  • Infections.
  • Medications.
  • Malignancy.
  • Vitiligo (with absent melanocytes).
  • Scleroderma/morphea.

Lymphocytes & plasma cells +/-eosinophils:

  • Erythema chronicum migrans (Lyme disease).

Lymphocytes (not tightly cuffed):

  • Viral exanthems.
  • Drug eruptions.

Lymphocytes & eosinophils:

  • Drug reaction.
  • Insect bite.
  • Dermatophyte infection.

A simple memory device - 6 Ls:[36]

  • Lymphoma.
  • Pseudolymphoma (cutaneous lymphoid hyperplasia, lymphocytoma cutis).
  • Lupus erythematosus.
  • Lymphocytic infiltrate of Jessner / tumid lupus erythematosus.
  • Polymorphous light eruption.
  • Lyme disease.

Neutrophils

DDx:[1]

  • Cellulitis.
  • Neutrophilic eccrine hidradenitis (idiopathic palmar-plantar hidradenitis)

With eosinophils:

  • Urticaria.

Eosinophils

DDx:[1]

  • Hypersensitivity reaction/drug reaction.
  • Insect bite.
  • Bullous pemphigoid, urticarial.

Mast cells

Vasculitis

General DDx:

  • Infection.
  • Autoimmune.
  • Malignancy.
  • Toxic (medications).

Small vessel:

Medium vessel:

Medium vessels often with small vessel involvement:

Large vessel:

Nodular and diffuse dermatitides

Neutrophils

With pus (suppurative)

Neutrophils only:

  • Follicular occlusion triad.
  • Ruptured cyst/follicle.

Neutrophils and eosinophils:

  • Halogenoderma.
  • Blastomycosis-like pyoderma (pyoderma vegetans) - due to bacterial infection, usu. S. aureus.

Without pus

With vasculitis:

Without vasculitis:

Lymphocytes

Plasma cells

Eosinophils

Histiocytes

Granulomatous

Sarcoidal
  • Sarcoidosis - have few lymphoid cells around them; thus called "naked granulomas".[2]
Tuberculoid
Foreign body-type granulomas
Palisaded granumolas

Blue granuloma:

Red granuloma:

See also

References

  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 Brinster NK (March 2008). "Dermatopathology for the surgical pathologist: a pattern based approach to the diagnosis of inflammatory skin disorders (part I)". Adv Anat Pathol 15 (2): 76–96. doi:10.1097/PAP.0b013e3181664e8d. PMID 18418089.
  2. 2.0 2.1 Brinster, NK. (Nov 2008). "Dermatopathology for the surgical pathologist: a pattern-based approach to the diagnosis of inflammatory skin disorders (part II).". Adv Anat Pathol 15 (6): 350-69. doi:10.1097/PAP.0b013e31818b1ac6. PMID 18948765.
  3. Kumar, Vinay; Abbas, Abul K.; Fausto, Nelson; Aster, Jon (2009). Robbins and Cotran pathologic basis of disease (8th ed.). Elsevier Saunders. pp. 1191. ISBN 978-1416031215.
  4. Kumar, Vinay; Abbas, Abul K.; Fausto, Nelson; Aster, Jon (2009). Robbins and Cotran pathologic basis of disease (8th ed.). Elsevier Saunders. pp. 1191. ISBN 978-1416031215.
  5. JAH. 20 February 2009.
  6. Crowson AN, Magro CM, Mihm MC (April 2008). "Interface dermatitis". Arch. Pathol. Lab. Med. 132 (4): 652–66. PMID 18384217. http://www.archivesofpathology.org/doi/full/10.1043/1543-2165%282008%29132%5B652%3AID%5D2.0.CO%3B2.
  7. URL: http://www.dermpedia.org/baby-dermpedia-for-beginners/discoid-lupus-erythematosus. Accessed on: 7 March 2012.
  8. Chen YJ, Wu CY, Huang YL, Wang CB, Shen JL, Chang YT (2010). "Cancer risks of dermatomyositis and polymyositis: a nationwide cohort study in Taiwan". Arthritis Res. Ther. 12 (2): R70. doi:10.1186/ar2987. PMC 2888225. PMID 20398365. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2888225/.
  9. Teichman, JM.; Sea, J.; Thompson, IM.; Elston, DM. (Jan 2010). "Noninfectious penile lesions.". Am Fam Physician 81 (2): 167-74. PMID 20082512.
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  15. Kumar, Vinay; Abbas, Abul K.; Fausto, Nelson; Aster, Jon (2009). Robbins and Cotran pathologic basis of disease (8th ed.). Elsevier Saunders. pp. 1192. ISBN 978-1416031215.
  16. Mitchell, Richard; Kumar, Vinay; Fausto, Nelson; Abbas, Abul K.; Aster, Jon (2011). Pocket Companion to Robbins & Cotran Pathologic Basis of Disease (8th ed.). Elsevier Saunders. pp. 604. ISBN 978-1416054542.
  17. URL: http://www.careforumwales.org/cell-carcinoma/histopathologic-terminology.html. Accessed on: 28 August 2011.
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  20. 20.0 20.1 20.2 Mitchell, Richard; Kumar, Vinay; Fausto, Nelson; Abbas, Abul K.; Aster, Jon (2011). Pocket Companion to Robbins & Cotran Pathologic Basis of Disease (8th ed.). Elsevier Saunders. pp. 603. ISBN 978-1416054542.
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