Thrombocytopenia

• See also Drug-induced thrombocytopenia

Differential Diagnosis

• Pseudothrombocytopenia
• Decreased production
  • Viral infection
  • Malignancy
• Destruction/Consumption
  • Immune-mediated thrombocytopenic purpura (ITP)
    • Primary ITP
    • Hepatitis C, HIV, and Helicobacter pylori; also CMV, EBV, VZV, Zika virus
    • Autoimmune: antiphospholipid syndrome, Evans syndrome, IBD, RA, SLE
    • CVID
    • CLL
    • Lymphoma
  • Drug-induced thrombocytopenia: abciximab, beta-lactams (including penicillins and cephalosporins), carbamazepine, epifitabide, gold compounds, heparin, linezolid, MMR vaccine, phenytoin, piperacillin, quinidine, quinine, rifampin, sulfonamides (including TMP-SMX), valproic acid, and vancomycin
  • Thrombotic microangiopathy
    • TTP/HUS, other TMAs
• Sequestration
  • Splenomegaly

Investigations

• Rule out secondary causes with hepatitis C virus, HIV, and Helicobacter pylori serology