Thrombocytopenia resident survival guide
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Ogheneochuko Ajari, MB.BS, MS [2]
Introduction
Thrombocytopenia refers to relatively few platelets in blood. A normal platelet count ranges from 150,000 to 450,000 per microliter of blood, determined by the 2.5th lower percentile of the normal platelet count distribution.
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
- Bone marrow suppression (for example chemotherapy, irradiation)
- Chronic alcohol use
- Chronic liver disease
- Congenital thrombocytopenia
- Disseminated intravascular coagulation
- Drug-induced thrombocytopenia (DITP)
- Gestational thrombocytopenia
- HELLP syndrome
- Hemolytic uremic syndrome
- Heparin-induced thrombocytopenia
- Immune thrombocytopenic purpura
- Infections
- Preeclampsia
- Pseudothrombocytopenia
- Thrombotic thrombocytopenic purpura
Management
Shown below are algorithms summarizing the approach to thrombocytopenia.
Characterize the symptoms: ❑ Easy bruising ❑Petechiae ❑ Rashes ❑ Melena ❑ Fevers ❑ Bleeding ❑ Headaches ❑ Abdominal pain ❑ Visual disturbances ❑ Weight loss ❑ Night sweats ❑ Bone pain History/Epidemiological factors: ❑ Recent medications ❑ Pregnancy ❑ Family history ❑ Medical history ❑ 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 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| B01 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| CO1 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| D01 | D02 | D03 | D04 | D05 | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| E01 | E02 | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Algorithm for Diagnosis of Thrombocytopenia based on the Peripheral Blood Smear
| Thrombocytopenia | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Platelet clumping | Examine peripheral blood smear | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| Pseudothrombocytopenia | True thrombocytopenia | Giant platelets ±WBC inclusions | Congenital/Hereditary thrombocytopenia | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Schistocytes | Spherocytes | Dacrocytes | Hypersegmented neurophils Macrocytosis | Neutrophilia Lymphocytosis Leukopenia Toxic granulations | Blasts | Isolated thrombocytopenia | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| DIC TTP/HUS | Evans syndrome Hypersplenism | Myelofibrosis | Vit. B12 deficiency Folate deficiency | Infections | Bone marrow disorders | ITP Drug-induced thrombocytopenia HIV, HCV H. pylori HIT DIC Gestational thrombocytopenia | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Do's
- Bone marrow biopsy should be done for patients that are older than 60 years of age to rule out myelodysplastic syndrome or lymphoproliferative disorders.
- Treatment should be considered for patients with platelet counts less than 30,000 per microliter.
Dont's
- Do not initiate cancer chemotherapy or antiviral therapy in the presence of thrombocytopenia.
- Do not start treatment for platelet counts greater than 50,000 per microliter unless actively bleeding.
- Don't give warfarin (coumadin) monotherapy to an acutely bleeding patient because it may induce thrombosis.