Thrombocytopenia resident survival guide

Revision as of 16:57, 23 October 2018 by Ssharfaei (talk | contribs)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigation Jump to search

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ogheneochuko Ajari, MB.BS, MS [2]

Overview

Thrombocytopenia is the decreased concentration of platelets below 150,000 cells per microliter of blood.

Causes

Life Threatening Causes

Life-threatening causes include conditions which may result in death or permanent disability within 24 hours if left untreated.

Common Causes

Management

Shown below is an algorithm depicting the initial approach to thrombocytopenia.[1]

 
 
 
Characterize the symptoms:
❑ Onset (acute, chronic, recurrent)
❑ Easy bruising
Petechia
❑ Rashes
❑ Melena
Fevers
Bleeding
Headaches
Abdominal pain
❑ Visual disturbances
Weight loss
❑ Night sweats
❑ Bone pain
Obtain a detailed history:
❑ Recent medications
❑ Pregnancy
❑ Family history
❑ Malignancy
❑ Recent infection
❑ Recent vaccinations
❑ Recent travels
❑ Recent transfusions
❑ Chronic alcohol use
❑ Recent hospitalization
❑ Recent organ transplantation
❑ Recent valve replacement surgery
❑ Dietary habits
❑ Sexual history
❑ Ingestion of quinine containing beverages
 
 
 
 
 
 
 
 
 
 
 
 
Examine the patient:
❑ Bleeding location
❑ Bleeding severity
Hepatomegaly
Splenomegaly
❑ Mucocutaneous bleeding
❑ Skeletal abnormalities
❑ Joint or soft tissue bleeding
Rash
❑ Generalized lymphadenopathy
❑ Skin necrosis
❑ Neurological exam
 
 
 
 
 
 
 
 
 
 
 
 
Order tests:
Peripheral blood smear
CBC and differential
Reticulocyte count
LDH
LFT
❑ Renal function test
❑ Clotting screen
PT
aPTT
Fibrinogen
Haptoglobin
D-dimer
❑ Request a hematology consult
 
 
 
 
 
 
 
 
 
 
 
 
❑ Order additional tests based on the results of the CBC-D and peripheral blood smear
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Possible Pseudothrombocytopenia
❑ Clumped platelets
 
 
 
True thrombocytopenia
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
❑ Order platelet count on heparinized blood specimen
 
Isolated thrombocytopenia
 
Thrombocytopenia with abnormalities in other blood lineages
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Guide your next step by specific findings
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Consider:
ITP
❑ Drug induced thrombocytopenia
HIV
HCV
H. pylori
DIC
❑ Gestational thrombocytopenia
 
Look for:
SchistocytesSpherocytes
❑ Dacrocytes ❑ Blasts
❑ Giant platelets ❑ Granulations
❑ Hypersegmented neutrophils
Macrocytosis
Lymphocytosis
Neutropenia
 

Note that the treatment of thrombocytopenia is specific to the underlying cause of thrombocytopenia.

Diagnostic Clues

Shown below is a table summarizing different findings on the peripheral blood smear findings and their associated conditions.[1]

Findings on the peripheral blood smear Associated conditions
Giant platelets Hereditary thrombocytopenia
Schistocytes DIC, TTP, HUS
Blasts Bone marrow disorder
Dacrocytes Myelofibrosis
Spherocytes
RBC clumping
Evans syndrome
Nucleated RBCs Hemolytic anemia, myelofibrosis, infiltration of the bone marrow
Lymphocytosis
Neutrophilia
Lymphocytosis
Leukopenia
Granulations
Infection
Macrocytosis
Hypersegmented neutrophils
Megaloblastic anemia e.g. vitamin B12 deficiency, folate deficiency
Leukemic cells Hematological malignancies
Pancytopenia Aplastic anemia, myelodysplastic syndrome, leukemia
Microspherocytes Evans syndrome, thrombotic angiopathies
Macrocytosis Vitamin B12 deficiency, folate deficiency
Parasites Malaria


Indications for Platelet Transfusion in Thrombocytopenia

Prophylactic Indications

  • Consider platelet transfusion in the following conditions if the platelet count is less than:
    • 50,000/μL: Major surgery[6]
    • 10,000/μL: Chemotherapy, bone marrow transplantation[7]
    • 20,000/μL: Aggressive therapy for bladder tumors or demonstrable necrotic tumors[6]
    • 10,000/μL: Treatment for acute leukemia [6]
    • 20,000/μL: Before a lumbar puncture[6]
  • Bone marrow aspirations and biopsies can safely be performed at platelet counts <20,000/μL.[6]

Therapeutic Indications

  • Platelet transfusions in patients with chronic thrombocytopenia is usually indicated with a WHO bleeding grade of ≥ 2.[7]
  • For invasive procedures, it is recommended that a platelet count of at least 50,000/μL be maintained.[7][8]
  • The extent of surgery, ability to control bleeding, presence of platelet dysfunction and other coagulation defects determines when to make a decision to transfuse with a platelet count between 50,000 and 100,000/μL.[7]
  • Platelet transfusion to control or prevent bleeding with trauma or surgical procedures require higher transfusion thresholds of 100,000/μL for neurosurgical procedures.[7]
  • An acutely bleeding surgical patient usually requires platelet transfusion if the platelet count is < 50,000/μL and rarely if the count is > 100,000/μL.[8]
  • In acute DIC and with substantial bleeding, it is recommended to maintain the platelet count around 50,000/μL.[8]
  • In ITP, the transfusion of platelets is indicated in major and/or dangerous cases of hemorrhage (e.g. intracranial or intraocular hemorrhage).[8]
  • In acquired or congenital disorders of platelet function, platelet transfusion is indicated only in cases of perioperative hemorrhage.[8]

WHO Bleeding Grades

Below is a table depicting the WHO bleeding grades for therapeutic platelet transfusion.[7][8]

Grade 0 Grade 1 - Minor bleeding Grade 2 - Mild bleeding Grade 3 - Major bleeding Grade 4 - Disabling bleeding
None Petechiae
Ecchymosis
Occult blood in body secretions
Mild vaginal spotting
Evidence of gross hemorrhage not requiring red cell transfusion e.g. Epistaxis, hematuria, hematemesis Hemorrhage requiring transfusion of 1 or more units of red cells/day Life threatening hemorrhage e.g. Intracranial hemorrhage, pericardial hemorrhage, pulmonary hemorrhage

Do's

  • Consider the following diagnoses in the following categories of patients:
    • Critically ill patients: leukemia, manifested by blasts, and thrombotic microangiopathy, characterized by the presence of schistocytes
    • Hospitalized patients: HIT and DIC
    • Cardiac surgery patients: mechanical destruction, hemodilution, drug induced thrombocytopenia
    • Patients undergoing PCI: Drug induced thrombocytopenia (GpIIb-IIIa inhibitors)
    • Pregnant women: Gestational thrombocytopenia, preeclampsia, ITP
  • If drug induced thrombocytopenia is suspected, stop the possible offending drug.
  • Consider isolated thrombocytopenia in patients with thrombocytopenia in the absence of any systemic symptoms and the absence of any abnormalities in the other blood cells lineages.
  • Order a bone marrow aspirate and biopsy in case of severe unexplained thrombocytopenia.[1]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 Stasi R (2012). "How to approach thrombocytopenia". Hematology Am Soc Hematol Educ Program. 2012: 191–7. doi:10.1182/asheducation-2012.1.191. PMID 23233580.
  2. 2.0 2.1 2.2 2.3 Greenberg EM, Kaled ES (2013). "Thrombocytopenia". Crit Care Nurs Clin North Am. 25 (4): 427–34, v. doi:10.1016/j.ccell.2013.08.003. PMID 24267279.
  3. Farid J, Gul N, Qureshi WU, Idris M (2012). "Clinical presentations in immune thrombocytopenic purpura". J Ayub Med Coll Abbottabad. 24 (2): 39–40. PMID 24397048.
  4. Nisha S, Amita D, Uma S, Tripathi AK, Pushplata S (2012). "Prevalence and characterization of thrombocytopenia in pregnancy in Indian women". Indian J Hematol Blood Transfus. 28 (2): 77–81. doi:10.1007/s12288-011-0107-x. PMC 3332269. PMID 23730013.
  5. Abdel Karim N, Haider S, Siegrist C, Ahmad N, Zarzour A, Ying J; et al. (2013). "Approach to management of thrombotic thrombocytopenic purpura at university of cincinnati". Adv Hematol. 2013: 195746. doi:10.1155/2013/195746. PMC 3876823. PMID 24396345.
  6. 6.0 6.1 6.2 6.3 6.4 Schiffer CA, Anderson KC, Bennett CL, Bernstein S, Elting LS, Goldsmith M; et al. (2001). "Platelet transfusion for patients with cancer: clinical practice guidelines of the American Society of Clinical Oncology". J Clin Oncol. 19 (5): 1519–38. PMID 11230498.
  7. 7.0 7.1 7.2 7.3 7.4 7.5 Slichter SJ (2007). "Evidence-based platelet transfusion guidelines". Hematology Am Soc Hematol Educ Program: 172–8. doi:10.1182/asheducation-2007.1.172. PMID 18024626.
  8. 8.0 8.1 8.2 8.3 8.4 8.5 Liumbruno G, Bennardello F, Lattanzio A, Piccoli P, Rossetti G, Italian Society of Transfusion Medicine and Immunohaematology (SIMTI) Work Group (2009). "Recommendations for the transfusion of plasma and platelets". Blood Transfus. 7 (2): 132–50. doi:10.2450/2009.0005-09. PMC 2689068. PMID 19503635.

Template:WH Template:WS