| What is purpura? | • The term purpura is used to describe red-purple lesions that result from the extravasation of blood into the skin or mucous membranes
– Purpura may be palpable or non-palpable (flat/macular)
– Macular purpura is divided into two morphologies based on size: Petechiae: small lesions (< 3 mm). Ecchymoses: larger lesions(>5mm)
• The type of lesion present is usually indicative of the underlying pathogenesis: i) Macular purpura is typically non-inflammatory
ii)Palpable purpura is a sign of vascular inflammation (vasculitis)
• All forms do not blanch when pressed. Diascopy refers to the use of a glass slide to apply pressure to the lesion in order to distinguish erythema secondary to vasodilation (blanchable with pressure), from erythrocyte extravasation (retains its red color)
• Purpura may result from hyper- and hypo-coagulable states, vascular dysfunction and extravascular causes |
| What is clinical presentation of purpura? | • A history and physical exam is often all that is necessary
• Important history items include: Family history of bleeding or thrombotic disorders (e.g., von Willebrand disease)
• Use of drugs and medications (aspirin, warfarin) that may affect platelet function and coagulation
• Medical conditions (liver disease) that may result in altered coagulation
• CBC with differential and PT/PTT are used to help assess
platelet function and evaluate coagulation states |
| What are causes of non-palpable purpura? | Petechiae (abnormal platelet fct, DIC and infection, increased venous pressure [idiopathic thrombocytopenia, drug-induced, thrombotic], some inflammatory skin diseases)
Ecchymosis (coagulation defects, DIC and infections, external trauma, skin weakness, Waldenstrom hypergammaglobulinemia) |
| What is palpable purpura? | • Palpable purpura results from inflammation of small cutaneous vessels (vasculitis)
• Vessel inflammation results in vessel wall damage and in extravasation of erythrocytes seen as purpura on the skin
• Vasculitis may occur as a primary process or may be secondary to another underlying disease
• Palpable purpura is the hallmark lesion of leukocytoclastic vasculitis (small vessel vasculitis) |
| How is morphology of vasculitis? | classified by the vessel size affected (small, medium,
mixed or large)
• Clinical morphology correlates with the size of the affected blood vessels :
-Small vessel: palpable purpura (urticarial lesions in rare cases, e.g., urticarial vasculitis)
-Small to medium vessel: subcutaneous nodules, purpura and FIXED livedo reticularis (also called livedo racemosa). Ulceration and necrosis may be present in medium-vessel vasculitis.
-Large vessel: claudication, ulceration and necrosis
• Diseases may involve more than one size of vessel
• Systemic vasculitis may involve vessels in other organs |
| What are small and medium vessel vasculitis? | • Small vessel vasculitis (leukocytoclastic vasculitis)
Henoch-Schönlein purpura
– Other: Idiopathic
– Malignancy-related
– Rheumatologic
– Infection
– Medication
• Urticarial vasculitis
– Predominantly Mixed (Small + Medium) ANCA associated
vasculitides
– Granulomatosis with polyangiitis (Wegener)
– Eosinophilic granulomatosis with polyangiitis (Churg-Strauss)
– Microscopic polyangiitis |
| What are other sized vasculitis? | • Essential cryoglobulinemic vasculitis
• Predominantly medium sized vessels Polyarteritis nodosa
• Predominantly large vessels Giant cell arteritis
• Takayasu arteritis |
| How is biological assessment of purpura? | • The following laboratory tests may be used to evaluate patient with suspected vasculitis: Urinalysis with micro (helps detect renal involvement)
• CBC with platelets
• ANA (a positive antinuclear antibody test suggests the presence of an underlying connective tissue disorder)
• ANCA (helps diagnose an ANCA-associated or drug-induced vasculitis)
• Complement (low serum complement levels may be present in mixed cryoglobulinemia, urticarial vasculitis and lupus)
• ESR (systemic vasculitides may have elevated sedimentation rates
• Also consider ordering RF (elevated in cryo vasculitis), cryoglobulins, an HIV test, HBV and HCV serology, occult stool samples, an ASO titer and streptococcal throat culture) |
| What is Henoch-Schönlein Purpura? | • Henoch-Schönlein Purpura (HSP) is the most common
form of systemic vasculitis in children Also called IgA
vasculitis
• Characterized by palpable purpura (vasculitis), arthritis,
abdominal pain and kidney disease
• Primarily a childhood disease (between ages 3-15), but
adults can also be affected
• HSP follows a seasonal pattern with a peak during the
winter presumably due to association with a preceding
viral or bacterial infection |
| How is general presentation of Henoch-Schönlein Purpura? | • Child between 4 and 7 y.o
• Vascular purpura by flare-ups predominant on
the extensor surfaces of joints
• Abdominal pain
• Arthralgia of the large joints of the lower
limbs.
• Histo: fibrinoid necrosis, leukocyte infiltration,
• DIF: IgA, C3 deposits in the vessel walls |
| How is dx of HSP? | • Diagnosis often made on clinical presentation, especially in children, +/- skin biopsy
• Skin biopsy shows leukocytoclastic vasculitis in postcapillary venules (small vessel disease) Immune complexes in vessel walls contain IgA deposition (the diagnostic feature of HSP)
• Rule out streptococcal infection with an ASO or throat culture
• It is also important to look for systemic disease:
• Renal: Urinalysis with micro, BUN/Cr
• Gastrointestinal: Stool guaiac
• HSP in adults may be a manifestation of underlying
malignancy
– Natural History: most children completely recover from
HSP Some develop progressive renal disease More common in adults
Tx: supportive +/- prednisone. |
| What are complications of HSP? | • Renal: proteinuria, hypertension
• Digestive: intussusception wall hematoma, volvulus, pancreatitis, intestinal acute, malnutrition...
• Resolutive bilateral Orchitis
• Neuro: peripheral or central
• Iatrogenic if corticosteroids
• Indications of renal biopsy: Pu > 1 g/d, HTA, renal
deficiency, Hu, unclean nephrotic syndrome |
| What is polyarteritis nodosa? | • Polyarteritis Nodosa (PAN) is a potentially systemic
disorder of necrotizing vasculitis of medium-sized
arteries Characterized by painful subcutaneous
nodules, which can ulcerate
• Patients may also present with livedo reticularis
• Unknown etiology; may affect any organ (most often
skin, peripheral nerves, kidneys, joints, and GI tract)
• PAN has been as |
| What are manifestations of PAN? | • - Vascular purpura, livedo, nodules, edema, necrosis
• - Fatigue, fever, patients of 40-60 years
• - Neurol: mononeuritis, rarely cerebral vasculitis
• - Rheumatol: myalgia, arthralgia
• - Kidney: myocardial infarction, hypertension, renal
failure
• - Digestive: abdominal pain, hemorrhage, mesenteric
infarction
• - Cardiovascular: myocarditis, peripheral ischemia
Several hyperpigmented nodules along medium-sized vessels |
| What are differences between cutaneous and systemic PAN? | . |
| How is the work up PAN? | • - Inflammatory syndrome
• - CBC: Hyperleukocytosis, Eosinophilia
• - Decrease of CH 50 and fractions, pANCA sometimes
positive, negative ANA, latex and Waaler rose negative
• - Sometimes positive HBV
• - Histo: segmental Vasculitis of medium and small
arteries, evolving by relapses, fibrinoid necrosis,
granulomas with neutrophils, thrombosis of blood
vessels (Lumina).
• - Treatment: general corticosteroids.
Cyclophosphamide; methotrexate |
