Platelets (PLT, thrombocytes) count

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Platelets count (PLT, thrombocytes)

Normal platelet count (thrombocyte count):

  • adults — 150,0–400,0*109/L
  • > 1 year — 180,0–320,0*109/L
  • < 1 year — 150,0–350,0*109/L
  • newborn — 100,0–420,0*109/L

The increase in platelet count — thrombocytosis (thrombocythemia) — can be primary, i.e. resulting from the primary proliferation of megakaryocytes, and a secondary, reactive, arising from any disease.

The decrease in the content of platelets in the blood — thrombocytopenia — can develop either as a result of insufficient production or increased platelet destruction .

Thrombocytosis (thrombocythemia)

Pathogenetic groups
Clinical forms, conditions
Primary Myeloproliferative diseases: chronic myeloid leukemia, myelofibrosis, erythremia.
1. Reactive
- in malignant tumors carcinoma, lymphoma, Hodgkin's disease
- in inflammatory diseases acute rheumatic fever, rheumatoid arthritis, ulcerative colitis, tuberculosis, osteomyelitis
- in acute anemia acute post-hemorrhagic, acute hemolytic anemia
- after surgery
within 2 weeks
2. After splenectomy. within 2 months



Thrombocytopenia groups
Clinical forms, conditions
I. Decreased platelet production (hematopoiesis insufficiency)
1. Acquired:  
- idiopathic idiopathic hematopoietic hypoplasia
- after viral infections viral hepatitis, adenovirus
- as a result of intoxication:  
  a) exogenous chemicals (benzene, insecticides), antibiotics (chloramphenicol, streptomycin), alcohol, ionizing radiation
  b) endogenous uremia, severe liver disease
- infectious-toxic viral or bacterial sepsis, miliary tuberculosis, typhus, toxoplasmosis
- in tumor diseases acute leukemia, myelodysplastic syndrome, myelofibrosis and osteomyelosclerosis, metastasis of carcinoma and sarcoma in bone marrow
- in megaloblastic anemia B12 and folic acid deficiency anemia.
- in paroxysmal night gemoglobinurii  
2. Hereditary: Fanconi syndrome, Wiskott-Aldrich syndrome, May-Hegglin anomaly, Bernard-Soulier syndrome


II. Increased platelet destruction

1. Immune:
- autoimmune  
  a) primary idiopathic thrombocytopenic purpura
  b) secondary in systemic lupus erythematosus, chronic active hepatitis, chronic lymphocytic leukemia etc.
- isoimmune in newborns (penetration of maternal antibodies), post-transfusion
- heteroimmune (hapten)  
  a) medicinal drug hypersensitivity
  b) viral virus-induced hypersensitivity
2. Destruction in the spleen hypersplenism in histiocytosis, storage diseases, lymphomas, hairy cell leukemia, spleen tuberculosis, myeloproliferative liver disease, portal hypertension
3. Platelets usage disseminated intravascular coagulation


Mean platelet volume (MPV)

Expressed in femtolitre or microns3. Normally, this indicator ranges from a 7.4 to 10.4 FL and has a tendency to increase with age. "Young" platelets have a larger volume, so the acceleration of thrombocytopoiesis the mean platelet volume increases.

The increase in MPV is observed in:

  • idiopathic thrombocytopenic purple
  • hyperthyroidism
  • atherosclerosis
  • diabetes mellitus
  • smokers and individuals suffering from alcoholism
  • myeloproliferative diseases

Mean platelet volume (MPV) reduction is observed after splenectomy in the Wiskott-Aldrich syndrome.


Platelet distribution width (PDW)

This indicator reflects the heterogeneity of platelet size (degree of anisocytosis). Normally platelet distribution width (PDW) is 10-20%.

Increased PDW may be a sign of the presence of platelets aggregates, microerythrocytes, platelets fragments. PDW changes in the myeloproliferative disorders.


Platelet crit (PCT, thrombocrit)

Platelet crit (PCT, thrombocrit) is a parameter that reflects the platelets proportion occupied in whole blood. In the norm thrombocrit is 0.15-0.4 %.