The Sticky Platelet Syndrome (SPS) is a common and hereditary cause of arterial and venous thrombosis which is easy to diagnose and to treat.
Inheritance: autosomal dominant
Patient characteristics:
(1) There is often a family history, typically with one parent having the syndrome.
(2) The onset often occurs when the patient is relatively young (5 to 45 years of age).
(3) The patient does not have other identifiable risk factor for thrombosis.
(4) The patient may have recurrent thromboembolic phenomenon while on adequate dosages of oral anticoagulants.
Clinical History: variety of arterial and venous thrombotic episodes
(1) deep venous thrombosis with or without pulmonary emboli
(2) coronary artery thrombosis
(3) cerebrovascular thrombosis
(4) transient ischemic attacks
(5) retinal vascular thrombosis
(6) peripheral arterial thrombosis
(7) fetal wastage syndrome
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History of Thrombosis
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Hyperaggregability of Platelets
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Diagnosis
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present
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only one concentration of only one reagent
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suggestive
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present
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only one concentration of only one reagent, similar results present on repeat testing
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firm diagnosis of SPS
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present
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two concentrations of one reagent
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firm diagnosis of SPS
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present
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one concentration of both reagents
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firm diagnosis of SPS
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Platelet Aggregometry
• platelet testing concentration: approximately 200,000 per µL
• concentrations of ADP: 2.34, 1.17, 0.58 µM (final concentration in cuvette)
• concentrations of epinephrine: 11, 1.1, 0.55 µM (final concentration in cuvette)
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Hyperagglutinability to ADP
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Hyperagglutinability to Epinephrine
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Type
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present
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present
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I
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absent
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present
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II
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present
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absent
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III
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Therapy:
• Low dose aspirin (acetylsalicylic acid, at 81 mg per day) is usually effective.
• If platelet aggregation does not normalize on low dose aspirin, higher doses (up to 325 mg/d) may be tried; if this fails to normalize the platelet aggregation, ticlopidine may be tried.
