Abstract: FR-PO137

Atypical Hemolytic Uremic Syndrome (aHUS) Presenting as Acute Heart Failure: A Rare Presentation Diagnosed on Skin Biopsy

Session Information

Category: Acute Kidney Injury

  • 003 AKI: Clinical and Translational

Authors

  • Gupta, Sanjeev, Westchester Medical Center, Valhalla, New York, United States
  • Chugh, Savneek S., New York Medical College, Valhalla, New York, United States
  • Papanagnou, Anastasios, Westchester Medical Center, Valhalla, New York, United States
  • Katchi, Tasleem, Westchester Medical Center, Valhalla, New York, United States
  • Chander, Praveen N., New York Medical College, Valhalla, New York, United States
Background

aHUS is associated with Complement over-activation secondary to regulatory gene mutations. Kidney is the most commonly involved organ due to unique characteristics of glomerular endothelium. Cardiac involvement occurs in about 3-10% cases with aHUS, can be severe with the acute presentation but, a diagnosis of aHUS remains unrecognized in many such cases. Cardiac manifestations include myocardial infarction, cardiomyopathy and heart failure (HF). Treatment of aHUS includes blockade of the terminal Complement pathway (C5b-9) however, spontaneous recovery can occur. We present a unique case of aHUS with primary cardiac involvement that affected kidney as well but, was diagnosed with specific manifestations on the skin biopsy.

Methods

A 24-year-old man presented with acute onset of shortness of breath. Initial workup revealed cardiogenic shock, acute kidney injury (serum creatinine 2.54 mg/dl) and thrombocytopenia (platelet count 69,000). Right heart catheterization showed an ejection fraction (EF) of 10% requiring intra-aortic balloon pump. Laboratory investigations revealed new onset hematuria with RBC casts, proteinuria (0.7gm), low hemoglobin (11.5 g/dl) and Haptoglobin (< 8), low C3, C4 and CH-50 and ADAMTS13 activity- 84%. ANA, p and c-ANCA, hepatitis panel and antiphospholipid Ab tested negative. The patient also developed a skin rash on the arm, which on biopsy showed features consistent with thrombotic microangiopathy (TMA) with positive staining for C3 and C4d. He underwent spontaneous clinical remission before initiation of complement blockade therapy. The patient was discharged following significant improvement of renal function, cardiac output (EF 35%) and normalization of platelet count.

Conclusion

aHUS is a rare disease with diagnosis resting on clinical, laboratory and pathological features. In a clinical setting of aHUS, performing kidney biopsy at times may not be feasible in the presence of thrombocytopenia and hence, a skin biopsy may provide diagnostic findings of TMA associated with microvascular staining of Complement and its metabolic products (C4d). HF is a grave complication of aHUS requiring a prompt diagnosis for initiation of treatment and resultant good long-term prognosis. A skin biopsy can show specific changes of TMA and be of diagnostic value.