• Finnish Medical Society Duodecim. Thrombocytopenia. In: EBM Guidelines. Evidence-Based Medicine [Internet]. Helsinki, Finland: Wiley Interscience. John Wiley & Sons; 2007 Apr 27 [Various].

This is the current release of the guideline.

This guideline updates a previous version: Finnish Medical Society Duodecim. Thrombocytopenia. In: EBM Guidelines. Evidence-Based Medicine [Internet]. Helsinki, Finland: Wiley Interscience. John Wiley & Sons; 2005 Apr 17 [Various].

The levels of evidence [A-D] supporting the recommendations are defined at the end of the "Major Recommendations" field.

Clinical Approach

• Stop drugs possibly causing thrombocytopenia unless vitally indicated.
• If the thrombocytopenic patient has symptoms of bleeding, immediate hospitalization is advisable.
• Remember the possibility of so-called pseudothrombocytopenia.

Basic Rules

• The pathophysiological mechanism of thrombocytopenia (blood platelet count <150 x 10⁹/L, in late pregnancy <120 x 10⁹/L) may be
  • Decreased production in the bone marrow
  • Increased consumption
  • Increased sequestration in the spleen
• Artificially low platelet counts are occasionally obtained when counted from ethylenediaminetetraacetic acid (EDTA)-anticoagulated blood (pseudothrombocytopenia). When thrombocytopenia (<100 x 10⁹/L) is detected in a patient for the first time, the same blood sample should be checked manually for the presence of thrombocyte aggregates.
• Thrombocytopenia is a symptom, the cause of which should be clarified. Typical manifestations of thrombocytopenia are skin bruising and petechiae and mucous membrane bleeding. In particular, gum and nasal bleeding is common. Bleeding may also take place in the gastrointestinal and urinary tracts. Menorrhagia is also common.
• A tendency towards bleeding is uncommon if the platelet count is 50 to 100 x 10⁹/L. Platelet concentrations of 10 to 50 x 10⁹/L are frequently associated with spontaneous bleeding, and haemorrhages are often severe with platelet counts of <10 x 10⁹/L. Drugs that affect the platelet function (aspirin [ASA], clopidogrel) increase bleeding tendency already in a rather moderate thrombocytopenia.

Causes of Thrombocytopenia

Decreased Production

• Inborn causes
  • Inherited thrombocytopenias (rare)
  • Fanconi's anaemia
• Acquired causes
  • Aplastic anaemia
  • Bone marrow infiltrates (carcinoma, leukaemia, myelofibrosis, myelodysplasia, tuberculosis)
  • Ionizing radiation, other causes of myelosuppression (cytotoxic chemotherapy)
  • Drugs (trimethoprim-sulfamethoxazole, gold, thiazide diuretics, oestrogens, interferons)
  • Deficiency of vitamins and other essential trace elements or nutrients (B₁₂, folate, iron)
  • Viral infections
  • Heavy drinking
  • Pregnancy

Increased Consumption

• Inborn causes
  • Non-immunological (haemolytic disease of the newborn, prematurity, maternal pre-eclampsia, infections)
  • Immunological alloimmune neonatal thrombocytopenia, maternal idiopathic thrombocytopenia purpura (ITP)
• Acquired causes
  • Non-immunological (infections, disseminated intravascular coagulation, thrombotic thrombocytopenic purpura, haemolytic-uraemic syndrome, drug-induced over-consumption of platelets)
  • Immunological (drug-induced, following blood transfusion, chronic and acute ITP) (see the Finnish Medical Society Duodecim guideline: "Bruises and purpura in children: ITP and its differential diagnosis")

Platelet Sequestration

• Hypersplenism

Loss of Platelets

• Acute haemorrhage
• Haemoperfusion

Clinical Approach

Symptomless Patient, Platelet Count 100–150 x 10⁹/L

• The general practitioner can safely follow the situation, initially at intervals of a few months. If no underlying disease becomes evident and thrombocytopenia remains stable, no further follow-up is required. All drugs causing thrombocytopenia should be avoided if possible. Alcohol consumption habits should be discussed.
• Many drugs cause thrombocytopenia relatively frequently (George et al., 1998) [C]. These include heparin, quinidine, chloroquine, gold, salicylates, sulphonamides, thiazides, allopurinol, phenytoin, carbamazepine, and trimethoprim.
  • Non-steroidal anti-inflammatory drugs (NSAIDs) (especially acetylsalicylic acid) and some other medicines (clopidogrel) frequently impair platelet function and bring about a bleeding tendency. This tendency is disproportionately strong among thrombocytopenic patients.
  • Paracetamol appears not to impair platelet function.

Symptomless Patient, Platelet Count <100 x 10⁹/L

• Thrombocytopenia-causing drugs should be stopped. Basic investigations are performed: haemoglobin, leucocyte count and differential, platelet count, and bone marrow examination.
• If the situation does not improve, referral to a specialist in internal medicine or haematology is advisable.
• If there are no obvious reasons for thrombocytopenia, platelet antibody assessment should be carried out early.

If a Thrombocytopenia Patient Has Symptoms of Bleeding

• He/she needs specialist care.
• It is important to detect the possible cause. Remember that the list of drugs possibly causing thrombocytopenia is very long. All these drugs should be avoided.

Idiopathic Thrombocytopenic Purpura (ITP)

• Treatment is planned by a specialist in internal medicine, a paediatrician, or haematologist.
• In adults, predniso(lo)ne continues to be the first-line therapy. The starting dose is 1 to 2 mg/kg/day. Response to treatment is often achieved in 1 to 4 weeks. At least a partial response is observed in 70 to 90% of cases, but a good one (i.e., platelet count >100 x 10⁹/L) in only 30 to 50% of the patients. After a maximal response is observed, the drug is slowly (over weeks) tapered to the smallest dose resulting in an acceptable clinical situation, say a platelet count >50 x 10⁹/L, with no symptoms of bleeding. ITP in children is often a self-limited postinfectious condition (see the Finnish Medical Society Duodecim guideline: "Bruises and purpura in children: ITP and its differential diagnosis").
• Intravenous gammaglobulin infusions may induce a response faster than corticosteroids. Non-responders are treated with immunosuppressants or splenectomy.
• Fibrinolysis inhibitors may be used to reduce excessive mucous membrane haemorrhages, such as nasal, gastrointestinal, and urinary tract bleeding and menorrhagia. Platelet transfusions are effective if no platelet antibodies are present. Massive bleeding is compensated with red cells, fresh-frozen plasma, and platelet concentrates.

Related Resources

Other Evidence Summaries

• Oprelvekin may accelerate platelet recovery and reduce the need for platelet transfusion in chemotherapy-induced thrombocytopenia (Wilde & Faulds, 1998) [C].

Refer to the original guideline document for other Internet resources and related literature.

Definitions:

Levels of Evidence

1. Quality of Evidence: High

   Further research is very unlikely to change confidence in the estimate of effect

   • Several high-quality studies with consistent results
   • In special cases: one large, high-quality multi-centre trial

2. Quality of Evidence: Moderate

   Further research is likely to have an important impact on confidence in the estimate of effect and may change the estimate.

   • One high-quality study
   • Several studies with some limitations

3. Quality of Evidence: Low

   Further research is very likely to have an important impact on confidence in the estimate of effect and is likely to change the estimate.

   • One or more studies with severe limitations

4. Quality of Evidence: Very Low

   Any estimate of effect is very uncertain.

   • Expert opinion
   • No direct research evidence
   • One or more studies with very severe limitations

None provided

Concise summaries of scientific evidence attached to the individual guidelines are the unique feature of the Evidence-Based Medicine Guidelines. The evidence summaries allow the clinician to judge how well-founded the treatment recommendations are. The type of supporting evidence is identified and graded for select recommendations (see the "Major Recommendations" field).

• Finnish Medical Society Duodecim. Thrombocytopenia. In: EBM Guidelines. Evidence-Based Medicine [Internet]. Helsinki, Finland: Wiley Interscience. John Wiley & Sons; 2007 Apr 27 [Various].

Not applicable: The guideline was not adapted from another source.

2001 Apr 30 (revised 2007 Apr 27)

Finnish Medical Society Duodecim - Professional Association

Finnish Medical Society Duodecim

Editorial Team of EBM Guidelines

Primary Author: Esa Jantunen

Not stated

This is the current release of the guideline.

This guideline updates a previous version: Finnish Medical Society Duodecim. Thrombocytopenia. In: EBM Guidelines. Evidence-Based Medicine [Internet]. Helsinki, Finland: Wiley Interscience. John Wiley & Sons; 2005 Apr 17 [Various].

None available

None available

This summary was completed by ECRI on December 17, 2002. The information was verified by the guideline developer as of February 7, 2003. The summary was updated by ECRI on April 2, 2004, on October 5, 2004, and June 28, 2005. This summary was updated by ECRI on January 31, 2006, following release of a public health advisory from the U.S. Food and Drug Administration regarding the use of WinRho SDF (Rho(D) Immune Globulin Intravenous [Human]). This NGC summary was updated by ECRI Institute on January 7, 2008.

This NGC summary is based on the original guideline, which is subject to the guideline developer's copyright restrictions.