Purpura and microvascular occlusion Flashcards
When does warfarin necrosis usually occur?
3-5 days post commencing warfarin
5 types of PPD
Shamberg’s disease
Itching purpura (eczematid like purpura of doucas and kapetanakis)
Pigmented purpuric lichenoid dermatoses of Gougerot and Blum
Lichen aureus
Pupura annularis telangiectoides (Majocchi’s)
Atrophie blanche associated with
Associated with chronic venous hypertension and varicosities but this form does not have surrounding livedo reticularis, also seen in Antiphospholipid ab related syndromes, sickle cell ulcers.
2 classic triads of cholesterol embolic
1: leg/foot pain + livedo reticularis + preservation of good peripheral pulses
2: livedo reticularis, renal insufficiency and eosinophilia.
Achenbach’s syndrome (paroxysmal finger haematoma)
Recurrent painful bruising on palms & palmar aspects of fingers, likely venous rupture.
What to exclude if you suspect PPD
MF
Drug causes
Infections eg beta haemolytic strep
Who gets ppd of gougerot and Blum?
Men between 40-60.
Degos disease aka
Malignant atrophic papulosis
Classification of purpura
1) petechiae
2) macular erythema
3) ecchymoses
4) palpable pupura
5) inflammatory retiform
6) non inflammatory retiform
Histology of PPD
perivascular infiltrate of lymphocytes and macrophages is centered on the superficial small blood vessels of the skin. Signs of endothelial cell swelling and narrowing of lumina may be seen. RBC extravasation and haemosiderin. Perl’s to confirm haemosiderin and Fontana-Masson to exclude melanin
tx of Sneddons
No effective treatment.
Avoid smoking, OCP
Treat HTN, hyperlipidaemia
Antiplatelets in longer term, thrombolytic and vasodilators
If antiphospholipid abs or lupus anticoagulants: warfarin.
Important hx factors in retiform pupura
Sx of infection, exacerbation in cold
Hx of thrombotic disease, renal disease, haematological disease, CV disease, connective tissue disease
Fam hx of thrombotic disease
Drug hx eg warfarin, levamisole in cocaine.
Miscarriage hx
Red flags for purpura
- Larger or variably sized esp when no in sun damaged skin
- Numerous or widespread lesions
- Lesions occurring in crops
- Palpable lesions
- reticulate
- Associated features eg pustules, necrosis, nodules, splinter haemorrhages
- Evidence of bleeding from other sites eg haematuria
- Associated general sx
Investigation of suspected occlusive syndromes
FBC, coags, elfts, ancas, biopsy
Causes of retiform pupura
Non-inflammatory: microvascular occlusion, protein C and S deficiency, cholesterol emboli
Inflammatory occlusion:
-IgA vasculitis
-mixed cryo, rheumatic, PAN, microscopic polyangiitis, wegeners, churg-strauss), livedoid vasculopathy, septic vasculitis, pernio, PG.
-Calciphylaxis, heparin or warfarin necrosis, antiphospholipid ab syndrome
Ix of retiform pupura
Skin biopsy – incisional : centre (rook) and edge. If infection suspected: culture
FBC, film, elfts, hep B,C
Coags, ANCAs, serum EPP, RF, ANA, C3, C4, factor V leidin, Protein C/S
Cardiolipin abs, beta2 glycoprotein I antibodies, lupus anticoagulant.
If acral/cold: cryoglobulins, cryofibrinogen
Causes of palpable pupura
- LCV, urticarial vasculitis
- small and medium vessels (mixed cryoglobulinaemia, rheumatic)
- ANCA associated (Wegeners, microscopic polyangiits, churg-strauss), EED, Sweets
- EM, PLEVA, PPD, hypergammaglobulinaemic pupura of waldenstrom
What is the Rumpel-Leede sign
Capillary leakage post BP cuff when pressure released. Can be checked by the Hess test (inflate to 80mmHg for 5 min), count petechiae just below the antecubital fossa. >5 is abnormal. May occur in ehlers dnalos (IV), some platelet dysfunction ,HHT
Who gets shamberg’s?
Mainly young adult males
Generalised livedo racemosa or livedo reticularis with CV lesions that cause focal neurological symptoms or signs. Associated Raynauds or acrocyanosis
F>M, typically in 4th-5th decades of life
sneddons
Acroangiodermatitis (of Mali), pseudo-kaposi’s sarcoma
Associated with venous insufficiency or with vascular anomalies eg klippel-trenaunay. M>F
Lower legs, dorsum feet and toes.
Due to abnormal vasculature.
Who gets itching ppd?
Usually adult men
pupura at friction sites - think of…
Clothing contact, capillaritis,HSP, Ehlers-danlos
Causes of neonatal pupura
- Deficiency of clotting factors/coagulation
- Thrombocytopenia
- Blueberry muffin
- TORCH
- Wiskott-aldrich
- Maternal ab-mediated.
- Associated with haemangioma
Who gets majocchi’s ppd?
Adolescents and young adults
Ix of atrophie blanche
Venous and artierial Doppler
Ana, antiphospholipid abs
Most common cutaneous findings of antiphospholipid syndrome
Livedo, leg ulcers, pseudovasculitis, digital gangrene, cutaneous necrosis and splinter haemorrhages.
Causes of petechiae
Low platelets, dysfunctional platelets, scurvy, waldenstroms macroglobulinaemia, fixed increased pressure (eg BP cuff), valsalva
What to think if ears are involved
Cryoglobuluinaemia, and other hyperviscositiy disorders
Levamisole, propylthiouracil
Clinical and lab criteria of antiphopholipid syndrome
Clinical criteria:
Vascular thrombosis
Complications of pregnancy eg >10 weeks, premature births or 3 or more unexplained consecutive abortions before 10 weeks.
Lab criteria
Antiocardiolipin abs on 2 or more occasions at least 6 weeks apart.
Lupus anticoagulant abs on 2 or more occasions at least 6 weeks apart
Beta 2 glycoprotein on 2 or more occasions at least 6 weeks apart.
Causes of occlusion due to platelet plugs
Heparin, essential thrombocytosis, polycythaemia, paroxysmal nocturnal haematuria, TTP/HUS
Broad categories of causes of microvascular occlusion
Platelet plugs Infection cryogelling embolus coagulopathies reticulocyte occlusion Other: calciphylaxis, hydroxyurea, spider and snake bites , intravascular lymphoma
Mechanisms of simple haemorrhage (5)
1) thrombocytopenia
2) platelet dysfunction
3) regional or localised increase in pressure
4) abnormal vascular support eg Ehlers danlos, scurvy, amyloidosis, PXE
5) capillaritis
What causes warfarin blue toe syndrome?
Cholesterol emboli
Causes of occlusion due to vessel organisms
ecthyma gangrenous, Lucia, vessel invading fungi, disseminated strongyloides
What are some neoplasms/tumours to consider in the differential of pupura
kaposi’s sarcoma, angiosarcoma, bacillary angiomatosis
Tx of PPD
Pruritis: antihistamines and topical steroids
Venous stasis: compression
Avoid dependency
nbUVB: shamberg and lichenoid
PUVA: schamberg and lichen aureus and lichenoid
lichen aureus: case report of topical pimecrolimus, PUVA
Case reports of griseofulvin, CsA, vit C 500mg bd + rutoside 50mg bd.
What to think of if eyelids are involved
Increased venous pressure
Coughing, vomiting, post endoscopy
Amyloidosis (panda sign)
Neuroblastoma
