A 57-year-old female was referred to GIM for incidental finding of pancytopenia. They initially presented to the ED with complaints of retrosternal chest discomfort and dyspnea.
- What hematologic emergency is suggested by the CBC?
- What is the next best test?
- Bonus question: what test is required to confirm the diagnosis?
Click for answer:
Diagnosis: Microangiopathic Hemolytic Anemia (MAHA), confirmed Thrombotic Thrombocytopenia Purpura (TTP)
CBC Clues:
(1) Severe thrombocytopenia
Q1: What hematologic emergency is suggested by the CBC
MAHA
Q2: What is the next best test?
Peripheral blood smear
Bonus question: what test is required to confirm the diagnosis?
ADAMTS13 activity testing
MAHA Differential
• TTP
• Hemolytic uremic syndrome (HUS)
• Atypical HUS (aHUS)
• DIC
• HELLP
• Drug-induced
MAHA is a term used to describe various hematologic conditions that cause hemolysis in the small vessels of the body. Platelets are also activated and consumed in this process. The end-result is organ damage, including the renal, neurologic, and cardiac systems most often. However, any vascular bed can be affected.
CBC Pearls
- Always consider MAHA with anemia + thrombocytopenia
- Blood smear is the next best test to examine for schistocytes
- MAHA is a hematologic emergency
Whenever you see anemia and thrombocytopenia, particularly in an acutely ill patient, you must consider MAHA. It is considered a hematologic emergency and requires urgent intervention, usually through plasma exchange or biologic administration. The differential for MAHA is listed in the Box.
The next best test would be to order a peripheral blood smear to look for schistocytes. These are classically associated with MAHA and any comment of schistocyte should serve as a red flag. The confirmatory test for TTP (a type of MAHA) is to send ADAMTS13 activity testing.