Thrombotic Microangiopathy: The Importance of Early Identification and Differentiation
Category: Nephrology Education
- 1302 Fellows and Residents Case Reports
- Brunson, Otis H, University of South Alabama College of Medicine, Daphne, Alabama, United States
- Perry, Christopher T, University of South Alabama , Mobile, Alabama, United States
- Bessette, Sabrina G., University of South Alabama College of Medicine, Daphne, Alabama, United States
The differentiation of Thrombotic Microangiopathy (TMA) is difficult due to overlapping features in presentation. Malignant hypertension-induced TMA (MH TMA) and atypical Hemolytic Uremic Syndrome (aHUS) are two of the more difficult etiologies of TMA to distinguish. Both can present with severely elevated blood pressures and classic TMA features: microangiopathic hemolytic anemia, thrombocytopenia, and renal failure. Rapid recognition of aHUS is important due to the vast improvement in prognosis with early Eculizumab initiation.
Presentation: A 59-year-old African American Female with PMH of hypertension presented with renal failure, anemia, and thrombocytopenia.
Diagnosis: A diagnosis of TMA was made based on lab findings and schistocytes on peripheral smear.
Intervention: Patient was initially treated for HTN emergency due to BP 181/115 mmHg on admission. She was then started on plasma exchange therapy, while ADAMSTS13 level was sent to rule out TTP. After ADAMSTS13 returned normal, an additional diagnosis of aHUS was considered. The decision was made to start Eculizumab while awaiting confirmatory aHUS genetic panel. The patient was treated with five weekly doses of Eculizumab.
Outcomes: Hematologic parameters and renal function improved on Eculizumab. Genetic panel returned normal, thus aHUS ruled less likely. The patient’s TMA was thus determined to be solely due to severe hypertension. The patient was discharged after blood pressure control and stabilization of Creatinine.
Our case highlights an important clinical point; in patients presenting with TMA and severe hypertension it is important to consider aHUS as a potential underlying diagnosis. Research shows that a subset of patients diagnosed with MH TMA have proven complement dysfunction, suggesting a close association between MH TMA and aHUS. Early treatment with Eculizumab is warranted due to better outcomes in kidney function and decreased progression to ESRD. Treatment with Eculizumab should be initiated as early as possible and before confirmatory genetic testing is completed.