Vasculitis Cutaneous vascular injury can be divided into two basic categories: vasculitis - PowerPoint Presentation

1. Vasculitis

2. Cutaneous vascular injury can be divided into two basic categories: vasculitis and vasculopathy. VasculopathyFibrinoid deposition, thrombosis with limited to no inflammation.Infiltration of vessel wall by inflammatory cells with otherwise minimal alteration.Leukocytoclasis of tissue infiltrate with minimal alteration of vessel, that is, swelling only, absence of fibrinoid necrosis. VasculitisPerivascular inflammatory cell infiltrate (neutrophilic, eosinophilic, lymphocytic, histiocytic, or mixed).Fibrinoid necrosis: necrosis of vessel wall with deposition of fibrinoid material.Other changes often present but not essential: edema, extravasation of erythrocytes, leukocytoclasis, infiltration of vessel wall by inflammatory cells, swelling of endothelial cells, luminal thrombosis.

3. Histologic manifestation of vascular damage Necrosis of vessel wall with deposition of fibrinoid material.Leukocytoclasis.Extravasation of erytherocytes.Luminal thrombosis.Endothelial cell swelling.Edema.

4. Classification of vasculitis:According to vessel size:Small vessel vasculitis e.g. Henoch-Schoenlein purpura.Small to medium sized vasculitis e.g. Anca associated vasculitides. Medium sized vasculitis e.g. polyarteritis nodosa.Large vessel vasculitis e.g. temporal arteritis.

5. Cutaneous Neutrophilic leukocytoclastic Small-Vessel Vasculitis A large number of different disease processes can be accompanied by small-vessel vasculitis with a neutrophil-predominant infiltrate. The clinical and histologic manifestations are thus fairly nonspecificExtensive palpable purpura associated with leukocytoclastic vasculitis.

6. Histopathological picture Neutrophilic small-vessel vasculitis is a reaction pattern of small dermal vessels, almost exclusively postcapillary venules, characterized by a combination of vascular damage and an infiltrate composed largely of neutrophils.Vascular damage.Swelling of endothelial cells Strongly eosinophilic strands of fibrin within and around their walls.If severe luminal thrombosis

7. The cellular infillterate The cellular infiltrate is present predominantly around the dermal blood vessels or within the vascular wallsThe infiltrate consists mainly of neutrophils and varying numbers of eosinophils and mononuclear cells. Because there is often fragmentation of neutrophil nuclei (karyorrhexis or leukocytoclasis), the term leukocytoclastic vasculitis is frequently used.Extravasation of erythrocytes is commonly present.Fibrinod necrosis Neutrophilic infiltrateExtravasated RBCs

8. If there is increased edema sbepidemal blister can occur in LCV that may appear clinically as vesicular lesion

9. Differential Diagnosis of Cutaneous Neutrophilic Small-VesselVasculitisInfection :Bacterial (gram-positive/gram-negative organisms, mycobacteria, spirochetes), Rickettsial, Fungal, ViralImmunologic injuryImmune complex-mediated: Henoch–Schönlein purpura, Urticarial vasculitis, Cryoglobulinemia, Serum sicknessConnective tissue diseases: SLE Autoimmune diseasesInfection-induced immunologic injury (e.g., hepatitis B or C, streptococcal)Drug inducedParaneoplastic processesAntineutrophil antibody associated: Wegener syndrome , Microscopic polyangiitis, Churg–Strauss syndrome.Unknown: Behçet disease, Erythema elevatum diutinum,Polyarteritis nodosa

10. Granuloma fasciale GF presents as one or several asymptomatic, soft, brown-red, slowly enlarging papules or plaques, almost always on the face of older individuals.Histopathology:A dense polymorphous infiltrate is present mainly in the upper half ofthe dermis but may extend into the lower dermis and occasionally even into the subcutaneous tissue. Quite characteristically, the infiltrate does not invade the epidermisor the pilosebaceous appendages but is separated from them by a narrow grenz zone of normal collagen. The pilosebaceous structures tend to remain intact. The polymorphous infiltrate consists primarily of neutrophils and eosinophils, but mononuclear cells, plasma cells, and mast cells also are present. Vascular damage in GF is seen but often limited, and thus perhaps GF is best termed a neutrophilic vascular reaction.

11. A: There is a cellular infiltrate in the dermis, separated from the epidermis by an uninvolved or grenz zone. B: The infiltrate contains numerous neutrophils and eosinophils. Vascular damage is minimal.Grenz zone eosinophils

12. Erythema Elevatum DiutinumThis rare condition is characterized by persistent, initially red to violaceous and later brown to yellow papules, nodules, and plaques. The lesions, typically distributed symmetrically on the extensor surfaces of the extremities, are initially soft and then evolve into fibrous nodules.Histopathology: In the early stage of EED, nonspecific LCV is observed. In later stages, granulation tissue and fibrosis form with a diffuse mixed-cell infiltrate showing a predominance of neutrophils.

13. Acase with erythema elevatum ditinum early lesion showing leukocytoclastic vasculitis. Fibinod deposit Perivascular and disperse neutrophilsNuclear dust

14. NEUTROPHILIC DERMATOSESseveral clinical conditions characterized by neutrophilic infiltrates rarely develop necrotizing vasculitis and need to be distinguished from vasculitis. These entities are categorized as neutrophilic dermatoses and are characterized by a neutrophilic infiltrate histologically lack of microorganisms on special stains and culturesclinical improvement on systemic steroid treatmentIt includes Sweet syndromePyoderma gangrenosumBowel-Associated Dermatosis–Arthritis Syndrome

15. Sweet syndromeA disease process, termed “acute febrile neutrophilic dermatosis,” that was characterized by abrupt onset of fever, leukocytosis, and erythematous plaques infiltrated by neutrophils. This condition typically occurs in middle-aged women after nonspecific infections of the respiratory or gastrointestinal tract. The lesions tend to be found on the face or extremities and only rarely involve the trunk and respond to steroid treatment. Histopathologically: typically, a dense perivascular infiltrate composed largely ofneutrophils is seen assuming a bandlike distribution throughout the papillary dermis. Vasodilation and swelling of endothelium with moderate erythrocyte Extravasation. prominent edema of the upper dermis are characteristic. In some instances, subepidermal blister formation may result

16. Two cases of sweet syndrome. There is a dense infiltrate in the upper dermis, consisting mainly of neutrophils. Derma edema is prominent in the papillary dermis.Papillary dermal edemaDense neutrophilic infiltrate

17. Pyoderma gangrenosumSeveral clinical types have been described: ulcerative PG with an undermined borderpustular PG with discrete, painful pustules painful bullae with progression to a superficial ulceration vegetative PG with a painless ulcer and a nonundermined exophytic border

18. A mixed inflammatory infiltrate in the dermis with spongiosis of the epidermis at the edge of the ulcer. Neutrophils andlymphocytes surround a vessel, but there is no frank vasculitis

19. LYMPHOCYTIC SMALL-VESSEL VASCULITISA histologic diagnosis of a lymphocytic vasculitis may be made if there is sufficient evidence of vascular damage and the inflammatory infiltrate is predominantly lymphocytic. Often, the vascular damage is subtle, and in many cases there may be disagreement among dermatopathologists on whether the term “vasculitis” is warranted.A small vessel is surrounded by an inflammatory infiltrate, the infiltrate is composed of lymphocytes

20. Differential Diagnosis of Lymphocytic Vasculitis and Lymphocytic Vascular ReactionsArthropod bitesDrug-induced and other hypersensitivity reactionsInfection-associated reactions (e.g., viral)Connective tissue diseasesBehçet diseasePurpuric dermatitidesPLEVA/PLC/LYPCutaneous lymphomaAutoimmune diseasesPernioPolymorphous light eruptionAtrophie blancheInfestations (e.g., scabies)

21. GRANULOMATOUS VASCULITIS ANDGRANULOMATOUS VASCULAR REACTIONS(Churg–Strauss Syndrome)several phases of disease development, from nonspecific symptoms of asthma and allergic rhinitis (prodromal phase) to a phase of hypereosinophilia with eosinophilic pneumonitis or gastroenteritis (second phase) and, finally, to systemic vasculitis (third phase).Two types of cutaneous lesions occur in about two thirds of all patients: (a) hemorrhagic lesions varying from petechiae or extensive ecchymoses to palpable purpuraand necrotic ulcers with associated areas of erythema (similar to Henoch–Schönleinpurpura).(b) cutaneous–subcutaneous nodules. The most common sites of skin lesions are the extremities

22. The areas of cutaneous hemorrhage typically show LCV. However, eosinophils may be conspicuous. In some instances, the dermis contains palisading necrotizing granulomas composed predominantly of radially arranged histiocytes and, frequently, multinucleated giant cells centered around degenerated collagen fibers.A: Scanning magnification shows a moderately dense cellular infiltrate with an ill-defined palisading pattern around areas of collagen degeneration. B: The infiltrate comprises mainly histiocytes, and collagen degeneration is prominent

23. (Wegener Granulomatosis)classic triad of this clinicopathologic complex characterized by (a) necrotizing and granulomatous inflammation of the upper and lower respiratory tracts.(b) glomerulonephritis.(c)systemic vasculitis.Histopathologically:The more frequent distinct reaction patterns include:Necrotizing/leukocytoclastic small-vessel vasculitis Granulomatous inflammation.The palisading granulomas resembling those of EGPA (CSS) may occur, except that the center of the GPA granuloma contains necrobiotic collagen and basophilic fibrillar necrotic debris admixed with neutrophils (the “blue” palisading granulomas).

24. A case with wegener granulomatosis showing palisading granuloma (arrows)

25. VASCULITIS AFFECTING MEDIUM-sized AND SMALLVESSELSPolyarteritis NodosaSystemic polyarteritis nodosa characterized by Fever, malaise, weight loss, weakness, myalgias, arthralgias, and anorexia. Renal affection, acute abdominal crises, strokes, myocardial infarction, and mononeuritis multiplexCutaneous polyarteritis nodosum may not be limited to the skin Cutaneous manifestations include subcutaneous nodules that may rarely pulsate or ulcerate, ecchymoses, livedo reticularis, bullae, papules.

26. A small artery in the subcutis is surrounded and partially obliterated by a cellular inflammatory infiltrateNecrotizing leukocytoclastic vasculitis, with eosinophilic change of the vessel wall,neutrophilic infiltration, and leukocytoclasiaAnother example of neutrophil-rich, medium-sized vasculitis with focal necrotizing features in a subcutaneous vessel in apatient with polyarteritis nodosa

27. Vascular occlusive conditionsDegos SyndromeA cutaneointestinal syndrome in which distinct skin findings (“drops of porcelain”) were associated with recurrent attacks of abdominal pain that often ended in death from intestinal perforations.The skin lesions of this syndrome arise in crops of asymptomatic, slightly raised, yellowish red papules that gradually develop an atrophic porcelain-white center. These papules tend to affect the trunk and proximal extremities.Histopathology: The classic lesion shows a wedge-shaped area of altered dermis covered by atrophic epidermis with slight hyperkeratosis. A sparse perivascular lymphocytic infiltrate may be seen,although the dermis is largely acellular. Typically, vascular damage is noted in the vessels at the base of the “cone of necrobiosis, morecharacteristically, intravascular fibrin thrombi may be noted, suggesting that the dermaland epidermal changes result from ischemia.

28. Atrophic epidermis overlies a wedge-shaped area of dermisa thrombosed vessel at the base