| Essential
thrombocytosis
REF: Dynamed Dec 2010
Making the diagnosis:
-
platelet count > 600,000/mm3
-
hemoglobin level < 13 g/dL or normal red cell mass
-
stainable iron in marrow or failure of iron trial (< 1 g hemoglobin rise
after 1 month)
-
no Philadelphia chromosome
-
collagen fibrosis of marrow absent or < 1/3 biopsy area without both
splenomegaly and leukoerythroblastic reaction
-
no known cause for reactive thrombocytosis
Physical Exam may revealed splenomegaly
Rule out: Differential Diagnosis
of Thrombocytosis:
1. Reactive thrombocytosis
Transient reactive thrombocytosis
-
trauma
-
major surgery
-
acute blood loss
-
rebound from thrombocytopenia
-
acute infection
-
acute inflammatory process
-
exercise
Persistent reactive thrombocytosis
-
iron deficiency
-
hemolytic anemia
-
chronic infection (such as tuberculosis)
-
chronic inflammatory disease
-
connective tissue disorders
-
temporal arteritis
-
inflammatory bowel disease
-
chronic pneumonitis
-
malignancy
-
absence of spleen
Medications
-
vincristine
-
all-trans retinoic acid
-
cytokines (interferons and interleukins)
-
growth factors (erythropoietin, granulocyte-colony stimulating factor)
-
corticosteroids (Platelets 2008 Sep;19(6):409)
2. Myeloproliferative disorders
-
chronic myelogenous leukemia
-
polycythemia vera
-
primary myelofibrosis
-
secondary myelofibrosis (post-polycythemic/post-thrombocythemic)
-
myelodysplastic syndrome with 5q-abnormality
-
refractory anemia with ringed sideroblasts and thrombocytosis (RARS-T)
3. Additional causes of reactive thrombocytosis
in children
-
Infections
-
31%-78% of all cases of reactive thrombocytosis in children
-
most common infectious causes are respiratory, gastrointestinal, and urinary
-
Sickle cell anemia
-
Juvenile idiopathic arthropathies
-
Kawasaki's disease
-
Malignancy (most often solid tumors in children)
|
Q-Notes
for Adult Medicine 
