Triston Berger, MD, Jaspreet Suri, MD, Daniel Boxer, MD Norwalk Hospital, Norwalk, CT
Introduction: Hemolytic uremic syndrome (HUS) is a thrombotic microangiopathy defined by hemolytic anemia, thrombocytopenia, and acute kidney injury. HUS can be categorized as typical in the presence of Shiga toxin-producing Escherichia coli, or atypical (aHUS). aHUS is caused by dysregulation of complement pathways from inherited or acquired abnormalities in complement proteins, or secondary to systemic disease. aHUS is exceptionally rare, with an incidence of 1 in 1,000,000. aHUS secondary to pancreatitis has been reported in few cases in literature, and the underlying pathogenic mechanism has yet to be elucidated. Pancreatitis has also been described as a rare extrarenal manifestation of aHUS. It is difficult to differentiate between the two, but genetic evaluation can provide some insight. We present a rare case of secondary aHUS from pancreatitis with negative genetic workup.
Case Description/Methods: A 35-year-old male with no medical history was brought in by ambulance after being found unresponsive. Initial labs revealed a glucose of 1375mg/dL, Creatinine 2.25mg/dL, lipase 1636U/L, hemoglobin 19.8g/dL, sodium 162mmol/L, and platelets 388x109/L. CT abdomen showed signs of pancreatitis. Two days later, his platelets dropped to 65x109/L. Further lab workup included low haptoglobin, elevated bilirubin, and schistocytes on peripheral smear. Coombs' test was negative. He developed anasarca and oliguria with creatinine increase to 11.7mg/dL and hemodialysis was initiated. Treatment with pulse dose steroids and plasmapheresis was started. ADAMTS13 levels returned normal, and Shiga toxin was negative. He was then started on eculizumab and evaluated for genetic complement mutations which returned negative, supporting secondary aHUS. Eculizumab was continued with return of renal function.
Discussion: Direct damage on the vascular endothelium from drugs, autoimmune diseases, infections, and cancer are well-known causes of secondary aHUS. aHUS secondary to pancreatitis has been described few times in literature. The underlying mechanism in the setting of acute pancreatitis remains elusive but may be related to release of activated enzymes causing endothelial damage and subsequent activation of proinflammatory cascades, leading to complement dysregulation and end-organ damage. The introduction of eculizumab, a C5 complement inhibitor, is now considered first line therapy and can prevent multi-organ damage. This case aims to provide more information in the diagnosis and management of this rare disease.
Disclosures:
Triston Berger indicated no relevant financial relationships.
Jaspreet Suri indicated no relevant financial relationships.
Daniel Boxer indicated no relevant financial relationships.
Triston Berger, MD, Jaspreet Suri, MD, Daniel Boxer, MD. C0069 - Secondary Atypical Hemolytic Uremic Syndrome Triggered by Acute Pancreatitis, ACG 2022 Annual Scientific Meeting Abstracts. Charlotte, NC: American College of Gastroenterology.
