Thrombocytopenia in cancer patients.

What Are Thrombocytopenia and ITP?

Dr. Sharat Damodar explains about platelet count drop

Cancer and thrombocytopenia

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Platelet counts are regulated by thrombopoietin, a hormone produced by the liver. This hormone acts on hematopoietic cells to differentiate and mature into megakaryocytes, contributing to the production of platelets. Thrombopoietin generally binds to c-Mpl receptor on platelets. In cases of low platelet counts, free thrombopoietin is cancer and thrombocytopenia prevalent, and the free hormone increases megakaryocyte and platelet production.

Conversely, free thrombopoietin levels decrease with higher platelet counts due to increased binding of thrombopoietin with platelet receptors, with subsequent clearance from circulation.

Hence, platelet production decreases, cancer and thrombocytopenia. Since platelets help in hemostasis, coagulation and clot formation, the concern in patients with thrombocytopenia is a greater risk of bleeding. Risk of bleeding is higher with counts less than 50, and risk of spontaneous bleeding is greatest with counts less than 10, Risk of bleeding is also higher in cases of decreased platelet production when compared to consumptive reasons. Platelet counts can be determined by examination of a blood sample.

Platelets generally have a lifespan of about days in cancer and thrombocytopenia blood, and can be lower in cases of thrombocytopenia. What is the differential diagnosis for this problem? Etiologies of thrombocytopenia can be organized into three broad mechanisms:. Aplasia or hypoplasia idiopathic, radiation, alcohol, or drugs for example, chemotherapy, thiazide diuretics, and certain antibiotics.

Ineffective hematopoiesis MDS, severe megaloblastic anemia in the setting of B12 or folate deficiency. The workup of thrombocytopenia begins with a detailed history and physical examination to help assess for possible etiologies, as well as manifestations of bleeding. History of mucocutaneous bleeding - Since platelets are very important in hemostasis, cancer and thrombocytopenia, a decrease in platelet count will predispose to mucosal bleeding, cancer and thrombocytopenia.

Epistaxis, gingival bleeding, rash or bruising on the skin, cancer and thrombocytopenia, menorrhagia or abnormal vaginal bleeding in women, rectal bleeding hematochezia or melenahematuria, bleeding after surgeries, or dental procedures.

History of substance abuse - especially alcohol use that can contribute to low platelet count. History of any recent infections or live virus vaccinations. History of recent travel, cancer and thrombocytopenia, animal contacts, bausch and lomb pharmaceutical vitamins insect bites.

History of recent medications - including prescription, over-the-counter, and herbal medication and supplements. There are clues in the physical examination that may prompt an evaluation of platelet count or suggest other diseases commonly associated with thrombocytopenia.

Abdomen - Splenomegaly - in some cases of thrombocytopenia, signs of liver disease including ascites, portal hypertension in cases of cirrhosis or in cases of lymphoma. Thrombocytopenia may occasionally be a spurious finding, often as a result of platelet clumping. Sending a separate platelet cancer and thrombocytopenia in a tube containing a non-EDTA anticoagulant i.

It is important to note whether the thrombocytopenia is occurring in isolation or if the CBC reveals involvement of other cell lines. A peripheral smear should be examined both for platelet morphology and to assess for abnormalities in other cell lineages. Large platelets may raise suspicion for a destructive etiology. Blasts or other immature whites blood cells, as well as dysplastic cells, may indicate leukemia or myelodysplasia; leukoerythroblastic findings can indicate myelophthisis; while spherocytes point to hypersplenism related to hereditary spherocytosis.

Other laboratory tests should be obtained based on the initial workup and history. Similarly, a clinical cancer and thrombocytopenia consistent with an auto-immune disorder might be worked up with ANA or antiphospholipid antibodies.

In unexplained cases, bone marrow aspiration and biopsy may be useful. It will establish etiology of bone marrow processes as well as malignancies, iron deficiency, and can also indicate infections. Ultrasound of the abdomen can help determine if splenomegaly is present. Ultrasound can also show presence of ascites and suggest cirrhosis in cases of liver disorders with portal hypertension, cancer and thrombocytopenia.

Primary ITP is mediated by platelet autoantibodies that accelerate destruction. Secondary ITP is related to an underlying condition: The cancer and thrombocytopenia presentation is one of insidious mucocutaneous bleeding. Primary ITP is a diagnosis of exclusion, made after other potential etiologies have been ruled out. There are no specific associated laboratory findings. Anti-platelet antibodies are neither sensitive nor specific, and are not required for diagnosis.

Both HUS and TTP fall in the spectrum of thrombotic microangiopathies, a pathological entity of abnormal arteriolar and capillary vessel walls, leading to microvascular thrombosis and thrombocytopenia with hemolytic anemia. In the case of TTP, this is due to a decrease in ADAMTS13 protease activity, leading to large von Willebrand Factor multimers on endothelial surfaces, cancer and thrombocytopenia, which in turn cause platelet aggregation and thrombosis.

H7 damages renal cancer and thrombocytopenia vascular endothelial cells. Presence of ADAMTS13 deficiency or inhibitor can be suggestive of TTP in the appropriate clinical context; however, the results are often not available in time to assist with immediate clinical cancer and blood glucose control making. Clinical manifestations and laboratory findings for HUS are similar to TTP, often occurring in children and cancer and thrombocytopenia with a prodrome cancer and thrombocytopenia bloody diarrhea secondary to enterohemorrhagic Breastfeeding and vitamins hda. Two forms of heparin-induced thrombocytopenia HIT exist.

HIT Type 1 is related to a direct effect of heparin on platelets and has little clinical significance. Heparin can generally be continued while the patient is observed. Clinical manifestations include both thrombocytopenia and a propensity for thrombosis. The onset is typically after days but can occur within 24 hours if cancer and thrombocytopenia has been prior heparin exposure in the past days. Cancer and thrombocytopenia low score has a negative predictive value of If diagnostic ambiguity remains or there is a discrepancy between clinical and laboratory findings, confirmatory testing with a functional assay i.

Antiplatelet antibodies have a low sensitivity and specificity for ITP. Demonstration of antibodies is not required for establishing the diagnosis of ITP. Management of Clinical Problem Thrombocytopenia. Most drug induced thrombocytopenia requires no specific treatment other than discontinuation of the offending medication.

There is no high quality evidence for the cancer and thrombocytopenia of cancer and thrombocytopenia. If clinical suspicion is high for HIT Type 2, heparin should be discontinued whilst the diagnostic workup unfolds, cancer and thrombocytopenia. Platelet transfusions may increase the risk of thrombotic events and should be reserved unless there is active bleeding, cancer and thrombocytopenia. Given the risk of thrombosis, the patient should be anticoagulated with a non-heparin anticoagulant i.

An overlap of at least 5 days is recommended. If TTP is highly clindamycin and lactobacillus, consultation with a hematologist is helpful in determining the need for urgent plasma exchange, in addition to administration of glucocorticoids. Spurious thrombocytopenia is not uncommon.

Clinicians should repeat a CBC and consider sending a platelet count in a non-EDTA collection tube before pursuing an extensive workup. N Engl J Med. No sponsor or advertiser has participated in, approved or paid for the content provided by Decision Support in Medicine LLC.

Historical information important in the diagnosis of this problem. Physical Examination maneuvers that are likely to be useful in diagnosing the cause of this problem. Laboratory, radiographic and other tests that are likely to be useful in diagnosing the cause of this problem C.

Management while the Diagnostic Process is Proceeding. Etiologies of thrombocytopenia can be organized into three broad mechanisms: Decreased platelet production Myeloproliferative or lymphoproliferative disorders acute or chronic leukemias, myelofibrosis. Increased platelet destruction or utilization Immune Destruction: Abnormal pooling or distribution Splenomegaly, massive transfusion, cancer and thrombocytopenia.

History of malignancy - any treatment with chemotherapy or radiation. Family history of bleeding or low platelet counts. General - pallor especially if has had bleeding episodes or associated with anemia b. Dermatologic - petechiae, purpura, bruising, ecchymoses or skin rashes c. Oral cavity - gingival bleeding, hemorrhagic blisters d.

Eyes - conjunctival or retinal bleeding e. Abdomen - Splenomegaly - in some cases of thrombocytopenia, cancer and thrombocytopenia, signs of liver disease including ascites, portal hypertension in cases of cirrhosis or in cases of lymphoma f. Lymphadenopathy - in some cases of infection, lymphoma, etc. Laboratory, radiographic and other tests that are likely to be useful in diagnosing the cause of this problem Laboratory assessment Thrombocytopenia may occasionally be a spurious finding, often as a result of platelet clumping.

Radiologic testing Ultrasound of the abdomen can help determine if splenomegaly is present. Idiopathic thrombocytopenic purpura Primary ITP is mediated by platelet autoantibodies that accelerate destruction. Heparin-induced thrombocytopenia Two forms of heparin-induced thrombocytopenia HIT exist. Powered By Decision Support in Medicine. You must be a registered member of Cancer Cancer and thrombocytopenia Advisor to post a comment, cancer and thrombocytopenia. By registering you consent to the collection and use of your information to provide the products and services you have requested from cancer and thrombocytopenia and as described in our privacy policy and terms and conditions.

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Cancer and thrombocytopenia

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