Use of Anti-C5 Inhibitor Leading to Renal Recovery in Combined Typical and Atypical Hemolytic Uremic Syndrome (HUS)
- AKI: Mechanisms - Case Reports
November 03, 2023 | Location: Exhibit Hall, Pennsylvania Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Acute Kidney Injury
- 103 AKI: Mechanisms
- Siu, Man Kit Michael, University of California Irvine, Irvine, California, United States
- Ferrey, Antoney Joseph, University of California Irvine, Irvine, California, United States
- Tantisattamo, Ekamol, University of California Irvine, Irvine, California, United States
Hemolytic uremic syndrome (HUS) is classified as typical vs atypical with very different approaches to management. Only around 10% of cases are atypical HUS, a rare disease with poor outcome caused by uncontrolled activation of the alternative complement pathway. Here we present a case of a patient admitted for AKI requiring initiation of dialysis with clinical features suggestive of both typical and atypical HUS manifestation. Use of anti-C5 inhibitor, Eculizumab, ultimately provided full renal recovery.
Patient is a 43 female, with no significant past medical history, and presented with nausea, vomiting, and bloody diarrhea. On admission, found to be in oliguric acute kidney injury (AKI), with hospital course complicated by worsening renal function and mental status requiring initiation of dialysis for clearance and volume optimization. Additional work up was significant for thrombocytopenia, elevated LDH, undetectable haptoglobin, with rare schistocyte concerning thrombotic microangiopathy (TMA). ADAMSTS13 29, given >10, not suggestive of TTP. O157:H7 grew on chromogenic agar with testing positive for Shiga toxin. As such, etiology of AKI initially thought secondary to typical HUS. However, given hemolytic anemia, thrombocytopenia, and kidney dysfunction, atypical HUS is still within the differential. Case discussed among transfusion medicine and nephrology team and patient was managed as atypical HUS with monoclonal anti-C5 inhibitor, Eculizumab 900mg weekly. Subsequent TMA complete genetic panel equivocal, but did show heterozygous missense for C5 polymorphism. Pt saw significant renal recovery after 4 doses of Eculizumab and was no longer dialysis dependent.
Eculizumab is recommended as first-line treatment for atypical HUS; but its use in typical HUS has been controversial. However, our case illustrates the difficult but importance of early consideration of aHUS in patients presenting with TMA. More importantly, we highlight that near-normal renal recovery may be attained with eculizumab in adults even after a dependence on dialysis.