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THROMBOCYTOPENIC PURPURA ICD-10: D69.3
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Thrombocytopenic purpura (TP) is characterized by cutaneous hemorrhages occurring in association with a reduced platelet count.
Occur at sites of minor trauma/pressure (platelet count <40,000/μL) or spontaneously (platelet count <10,000/μL).
Due to decreased platelet production, splenic sequestration, or increased platelet destruction.
Decreased platelet production. Direct injury to bone marrow, drugs (cytosine arabinoside, daunorubicin, cyclophosphamide, busulfan, methotrexate, 6-mercaptopurine, vinca alkaloids, thiazide diuretics, ethanol, estrogens), replacement of bone marrow, aplastic anemia, vitamin deficiencies, and Wiskott–Aldrich syndrome.
Splenic sequestration. Splenomegaly and hypothermia.
Increased platelet destruction. Immunologic: Autoimmune TP, drug hypersensitivity (sulfonamides, quinine, quinidine, carbamazepine, digitoxin, or methyldopa), after transfusion. Nonimmunologic: Infection, prosthetic heart valves, disseminated intravascular coagulation, and thrombotic TP (microangiopathic hemolytic anemia, thrombocytopenia, neurologic abnormalities, fever and renal disease).
Skin Lesions. Petechiae: Small (pinpoint to pinhead), red, nonblanching macules that are not palpable and turn brown as they get older (Fig. 20-1); later acquiring a yellowish-green tinge. Ecchymoses: Black-and-blue spots; larger area of hemorrhage. Vibices: Linear hemorrhages (Fig. 20-1), due to trauma or pressure. Most common on legs and upper trunk, but may occur anywhere.
Mucous Membranes. Petechiae: Most often on palate (Fig. 20-2) and gingival bleeding.
General Examination. Possible CNS and internal hemorrhage, anemia.
Laboratory Hematology. Thrombocytopenia.
Serology. Rule out HIV disease; antibodies against ADAMTS 13 (a protease).
Lesional Skin Biopsy (bleeding usually can be controlled by suturing biopsied site) to rule out vasculitis.
Differential diagnosis. Senile purpura, purpura of scurvy, progressive pigmentary purpura (Schamberg disease), purpura following severe Valsalva maneuver (coughing, vomiting/retching), traumatic purpura, factitial or iatrogenic purpura, and vasculitis.
Management. Identify underlying cause and correct, if possible. Oral glucocorticoids, high-dose IV immunoglobulins, or platelet transfusion for chronic (Immune Thrombocytopenic Purpura) ITP (splenectomy may be indicated).
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DISSEMINATED INTRAVASCULAR COAGULATION ICD-10: D65
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Disseminated intravascular coagulation (DIC) is a widespread blood clotting disorder occurring within blood vessels.
Associated with a wide range of clinical circumstances: Bacterial sepsis, obstetric complications, disseminated malignancy, and massive trauma.
Manifested by purpura fulminans (cutaneous infarctions and/or acral gangrene) or bleeding from multiple sites.
The spectrum of clinical symptoms associated with DIC ranges from relatively mild and subclinical to explosive and life threatening.
Synonyms: Purpura fulminans, consumption coagulopathy, defibrination syndrome, and coagulation fibrinolytic syndrome.
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AGE OF ONSET All ages; occurs in children.
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ETIOLOGY AND PATHOGENESIS
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