Keep Immune Thrombocytopenic Purpura (ITP) in your differential for patients with thrombocytopenia and evidence of bleeding. Although ITP has classically been described in children, it can occur in adults; especially between 3rd- 4th decade.
Thrombocytopenia leads to the extravasation of blood from capillaries, leading to skin bruising, mucus membrane petechial bleeding, and intracranial hemorrhage.
ITP occurs from production of auto-antibodies which bind to circulating platelets. This leads to irreversible uptake by macrophages in the spleen. Causes of antibody production include:
Medication exposure
Infection (usually viral), including HIV and hepatitis
Immune disorders (e.g., lupus)
Pregnancy
Idiopathic
Suspect ITP in patients with isolated thrombocytopenia on a CBC without other blood-line abnormalities. Abnormality in other blood-line warrants consideration of another diagnosis (e.g., leukemia).
ITP cannot be cured; treatments include:
Steroid to suppress antibody production (first-line therapy)
Intravenous immunoglobulin (IVIG)
IV Rho immunoglobulin (for Rh+ patients only)
Rituximab +/- dexamethasone
Splenectomy (rare cases of massive hemorrhage refractory to pharmacologic treatment)
