Thrombocytosis-elevated platelet count
Thrombocytosis or raised -Platelet count of greater than 450 x 109 also called Thrombocythaemia
Try and determine the cause – present in 1.5 to 2.2 % of the people aged > 40 seen in primary care REACTIVE-Overproduction of platelets- acute phase reactants More common ↑↑ cytokines due to any reason Platelet count normalizes or is expected to return to normal once the condition resolves Acute and chronic infection Haemorrhage Trauma , tissue damage Surgery Acute and chronic inflammatory conditions Rheumatological disorders Inflammatory bowel disease Coeliac disease Iron deficiency anaemia Hemolytic anaemia Post- splenectomy Solid malignancies Severe exercise Usually but not always associated with an ↑ ESR or CRP Platelets normally small with a normal mean platelet volume Blood film may show other features to indicate acute infective or inflammatory process
CLONAL-Clonal expansion of megakaryocytes Failure to regulate platelet production Myeloproloferative or myelodysplastic disorders Essential thrombocythaemia or essential thrombocytosis Chronic myeloid leukaemia – CML Polycythemia vera Primary myelofibrosis
Risk of myeloproliferative disorders is increased if presentation is with ↑ platelets along with erythrocytosis , leukocytosis , thrombosis or splenomegaly
history-Recent trauma or surgery Splenectomy Symptoms of infection or inflammation Bleeding , thrombosis or iron deficiency Any haematological diagnosis Constitutional symptoms – r/o malignancy ○ weight loss ○ fatigue ○ systemic complains Medications
Complications –Vasomotor symptoms Headache , visual symptoms , light-headedness , atypical chest pain , syncope , erythromelalgia ( redness & pain of the digits of hand /feet ) , acrocyanosis and visual changes Thrombosis Bleeding complications- from skin , gums or nose and blockage of arteries ( particularyl extreme thrombocytosis ) Splenomegaly Liver may also be enlarged
Risk of cancer and thrombocytosis- BJGP 2017 the incidence of cancer rose with age & with a higher platelet count & atleast 1/3rd of patients with lung and colorectal cancer with pre-disgnosis thrombocytosis had no other symptoms indicative of malignancy
Tests-FBC , Peripheral blood film , Ferritin Inflammatory markers as CRP , ESR , Plasma fibrinogen Reticulocyte count- r/o hemolytic anaemia Bone marrow aspirate or BM Trephine biopsy Molecular genetics
Referral- Platelet count > 1000 Platelet count 600-1000 and associated ○ recent arterial or venous thromboembolism ○ neurological symptoms ○ abnormal bleeding ○ age > 60 yrs Persistent unexplained counts > 600 on atleast two occasions 4-6 wks apart Persistent platelet count 450-600 in association with ○ previous h/o arterial or venous thrombosis ○ splenomegaly ○ elevated Hb or WCC Suspected or confirmed clonal cause Suspected malignancy
Reactive-Self limited Treat the underlying condition Little excess associated thrombotic risk Treat iron deficiency if present No antiplatelet therapy recommended
References
- Investigation and Management of Adults and Children Presenting with Thrombocytosis British Journal of Haematology British Committee for Standards in Haematology 2011
- Essential thrombocytosis BMJ Best Practice
- Thrombocytosis Victoria Brown MD et al Ferri’s Clinical Advisor 2018
- Thrombocytosis : Diagnostic Evaluation, Thrombotic Risk Stratification , and Risk-Based Management Strategies Thrombosis. 2011;2011:536062. doi: 10.1155/2011/536062. Epub 2011 Jun 8
- Oxford Handbook of Clinical Haematology
- Approach to the patient with thrombocytosis accessed via http://cursoenarm.net/UPTODATE/contents/mobipreview.htm? 1/7/1137?source=HISTORY
- Patient UK Thrombocytosis Clinical relevance of thrombocytosis in primary care : a retrospective cohort study of cancer incidence using English electronic medical records and cancer registry data Br J Gen Pract May 2017
- First Consult- Evaluation and initial management of thrombocytosis
- Investigating thrombocytosis BMJ 2019 ;366 : I4183 July 2019
- Basildon and Thurrock University Hospitals Thrombocytosis- GP Referral; guidelines
