Pupura and occlusion Flashcards
(14 cards)
Cause of macular petechiae
< 4mm
PLATELET RELATED
- REDUCED COUNT - TTP, DIC, Drug (chemo), BM (infiltration, fibrosis, failure)
- ABNORMAL FUNCTION - congenital, drug (Aspirin, NSAIDs), renal failure, BM (failure, infiltration eg myeloproliferative)
Mechanical - pressure, trauma
Vit C def - perifollicular
Mild inflam - PPDs, purpura of Waldenstrom
Cause of macular ecchymoses
> /=1cm –> all involve a component of minor trauma
IMPAIRED COAGULATION
- Drugs - anticoagulants
- Liver failure - impaired production of clotting cascade
- Vit K def - part of clotting cascade
- DIC (disseminated intavasc coag) - uses up clotting factors
- VWB disease
- Acquired/congenital thrombocytopenia
POOR DERMAL SUPPORT OF VESSELS
- Solar (elastosis) purpura
- SCS, TCS
- Vit C def
- EDS
- Systemic amyloidosis
Palpable purpura
Inflammatory purpura with prominent erythema
CSVV
- Idiopathic, Drug/Infection
- IgA
- Urticarial vasculitis
- EED (erythema elevatum diuntum)
- BADAS pustular vasculitis
- Hypergammaglobulinemia of Waldenstrom
Mixed vessel
- Cryoglobulinemias (mixed)
- Rheum vasculidities (RA, SLE, sjogrens)
Medium vessel
-ANCAS (MPA, GPA, EGPA)
Other disorders that may have vasculitis
- PPD
- Erythema Multiforme
- PLEVA
Retiform purpura (INFLAMMATORY)
INFLAMMATORY
VASCULITIS
-IgA
-All others are mixed/med - Cryo, rheum, ANCA, PAN
-Chilblains/pernio (localised vasculitis)
VESSEL OCCLUSION
- Livedoid vasculopathy
- PG
INFECTION
-Septic Vasculitis
Retiform purpura (NON INFLAMMATORY)
DDICC M
Drug - Heparin, warfarin (protein C def), levamisole adulterated cocaine
Deposition - Cholesterol, Calcium, Red cell (sickle cell), other
Infection - disseminated stongyloides, ecthyma gangrenosum, Lucio (lepromatous leprosy), Rocky mountain spotted fever.
Cold - Cryofibrinogen, Cryoglobulin, Cryoagglutinins
Coagulopathy
- Protein C/S def, Antiphospholipid
- Syndromes - ADA2, Degos, Sneddon
Malignancy - Angioinvasive B cell lymphoma, Myeloproliferative (thrombocytosis)
Pigmented purpuric dermatoses
- Schamberg
- Commonest, kids/adults, 50% familial.
- Lower legs, ASYMP yellow/brown patch + pinpoint petechiae (cayenne pepper) - Purpura Annularis Telangiectoides (PAT)
- Adolescent (any age) F>M. Can be exercise provoked.
- Purple/yellow/brown
- annular plaques with punctate teles/petechiae on border
- Few or many.
- NO rx - can last YEARS - Linear
- Kids, one limb, can look like shambergs or lichen aureus - Lichen aureus
- Patch yellow/brown, asymp commonly overlying perforating vessel of lower limb/ankle - Eczematoid like purpura of doucas and katenakis
- rare, middle age med
- similar to schambergs but itch ++
- Scaly, erythematous petechiae/pupuric macules lower limbs - Granulomatous
- Rare - Brown patches + haemorrhagic papules
- Histo shows granulomas
- Assoc with hyperlipidemia - PPLD of Gougerot and Blum = Pigmented purpuric lichenoid dermatitis
- Middle age, lower limbs
- Schamberg like + lichenoid papules
- Assoc porphyria. - Familial pigmented purpuric eruption
- Familial schambergs or familial PAT
- Childhood/adolescence
Histo and Rx of PPDs
Histo
- RBC extravastation
- Perivasc lymphocytic infiltrate
Note lichen aureus + lichenoid dermatitis of G&B
-Lichenoid reaction pattern
TREATMENT
- No specific Rx, symptomatic
- Compression stockings, rest/elevate
- ?trial restrict food additives
- TCS
- Abscorbic acid, CsA, griseo
- PUVA
Heparin induced thrombocytopenic syndrome (HITS)
WHO?
- <5% pts exposed to heparin
- 4 Scenarios: New cases; pts on long term heparin (eg dialysis) who have major operation OR no heparin but major operation or major infection
MOA
-Heparin binds to platelet factor 4 + IgG autoantibody –> forms immune complex depositied in vessels–> further plt aggregation/consumption.
Timing
- 5-7 days after exposure
- Late onset varient occuring 3 weeks later
- Not these autoAB last 100 days. Repeat exposure prior to 100 days clearance –> reoccurs within 24 hrs, can also get anaphylactoid rxn in 30 mins.
- May be once off event
CLINICAL
- At sites of injection OR distant sites (bc autoimmune)
- NON INFLAM Retiform purpura + central necrosis
- 30-50% develop thrombosis
Ix
- ELISA - Anti platelet factor 4 heparin complex
- PLT levels
- Screen infection
Histo - non inflam occlusion of BV
Rx
- CEASE heparin; Vit K antagonists (warfarin) CI in acute phase
- HITS + no thrombosis = Factor Xai (Danaparoid)
- HITS + thrombosis = Need anticoag 3/12
- Delayed/spontaneous - Agatroban, bivalirudin
- Recalcitrant = Plasma exchange.
Cryoglobulinemia, Cryofibrinogens, Cryoagglitinins
Cryoglobulins = immunoglobulins which precipitate with cold causing increased viscosity of blood
Type 1 (20%) - Due to monoclonal IgM (assoc lymphoprolif - CLL, MLL, B cell lymphoma) CLINICAL - Raynauds /acrocyanosis of helices/ livedo reticularis, purpura/ulcers,
MIXED (IgM and IgG)
Type 2 Hep C > lymphoprolif,
Type 3 - Infections/ Autoimmune (SLE, sjogrens, RA)
CLINICAL - palpable purpura + URTICARIAL lesions + systemic symptoms (HSM, cough/SOB, HTN, glomerulonephritis, visual disturbance, peripheral neuropathy)
Cryofibrinogens = fibrinogens precipitate in cold
Cold agglutinins = ABs cause agglutination and lysis of RBC on cold exposure
Ix
Cryoglobulins/fibrinogen
Hepatitis screen + LFTs
Autoimmune screen - inc complement (C4 low)
Rx
Cryoglobulinaemia
- min cold exposure
- control underlying blood dyscrasia or lymphoproliferative dx/ Treat Hep C.
- plasmapheresis or plasma exchange: ST benefit
cryofibrinogenaemia
- min cold exposure
- SCS + low dose aspirin
- maintenance: stanozolol
- immunosuppression, plasmapheresis, IV fibrinolysis
- thrombotic event: anticoagulation
- secondary cryofibrinogenaemia: treat assoc dx
cold agglutinin disease
- cold avoidance, ineffective in 75% pt
- rituximab (50% response rate)
Disseminated strongyloides- classic clinical presentation
Retiform purpura with periumbilical preliction.
Larvae in capillaries
Rx oral ivermectin
What is lucio phenomenon
Seen in Diffsue non nodular Lepromatous Leprosy Thrombotic lesions (vs EN leprosum which is vasculitis)
Retiform purpura –> chronic ulcers
Cholesterol emboli
- Who
- What scenario
- Clinical
- DDx
- Histo
- Rx
M>F
4 scenarios - Catheterization, acute thombotic therapy, prolonged anticoagulation (1-2/12), Unknown
Clinical
Livedo reticularis and cyanosis > retiform purpura
Toes/lower limbs
+/- nodules, purpura, ulcers/gangrene
Systemic sx - fever, weight loss, myalgias, altered mental state
Sequelae - TIA, CVA, RF
DDX
-Calciphylaxis, cold agglutination, antiphospholipid
Histo: Clefts + thrombi in arteriole at dermal-SC junction
Rx - No std care.
- Supportive, stop anticoagulation (unless severe RF)
- May attempt to eliminate embolism (stent)
- Aspirin/antiplatelets, Statins.
Warfarin induced necrosis
F>M, 6-7th decade
EARLIER than heparin 2-5 days (vs 5-10 days)
-Rare late onset 6/12 poor compliance/poor dosing
Due to drop Protein C
LOCALISED (vs widespread bc not immune complex)
-Site of abundant SC fat = Breast, hips/thighs, buttocks
Rx
- Cease
- Protein C concentrate, Vit K
- Change to heparin.
Protein C and S deficiency
- When occur
- Clinical presentation
- Rx
Clinical presentation is purpura fulminans
Neonatal pupura fulminans
(1) Congenital Protein C def
few hrs-5/7 post birth if untreated
Non-inflam retiform purpura + necrosis
visceral organ involvet
+/- cerebral/ retinal artery thrombosis occlusion/congenital blindness at birth
Rx:
- IV protein C concentrate or FFP initially,
- Lifelong anticoagulation - warfarin/LMWH
(2) Acquire in context Gp B strep
(3) Sepsis
Meningococcal infection, sepsis syndromes (s aureus, group A&B haemolytic strep, strep pneumoniae, haemophilus influenzae, H aegytius)
(4) Post infective
Children and adults; 7-10/7 after initial infection
Antibody that affects protein S function
During recovery period from group A strep infection, varicella-zoster, HHV-6 infection
Rx: plasma exchange/ plasmaphoresis/ plasma replacement + SCS + LMWH + IVIG
