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Abstract: PUB470

Atypical Hemolytic Syndrome (aHUS) Presenting as Acute Pulmonary-Renal Syndrome Preceded by Ocular Manifestation: A Very Rare Presentation

Session Information

Category: Glomerular

  • 1004 Clinical/Diagnostic Renal Pathology and Lab Medicine


  • Gupta, Sanjeev, Westchester Medical Center, Valhalla, New York, United States
  • Chugh, Savneek S., New York Medical College, Valhalla, New York, United States
  • Abdelrahman, Magdi H, Westchester Medical Center, Valhalla, New York, United States
  • Papanagnou, Anastasios, Westchester Medical Center, Valhalla, New York, United States
  • Chander, Praveen N., New York Medical College , Valhalla, New York, United States

Atypical hemolytic uremic syndrome (aHUS) is a systemic disease characterized by excessive complement activation in the microvasculature. Kidneys are most commonly involved organ while pulmonary and retinal involvement is very rare and usually discovered at autopsy. We present a case of aHUS mediated acute pulmonary-renal syndrome with ocular involvement.


A 32-year-old man with a history of Crohn’s disease s/p bowel resection was admitted with seizures, acute respiratory failure and acute kidney injury (creatinine-8.5 mg/dl). He also had a very recent history of bilateral eye blindness, resolved with steroid treatment. Laboratory findings showed hemoglobin 6.8 g/dl and platelet count 96,000). Chest X-ray showed diffuse bilateral interstitial infiltrate; bronchoscopy revealed diffuse pulmonary hemorrhage with a normal ejection fraction noted on echocardiogram. A diagnosis of pulmonary-renal syndrome was considered and he was started on IV steroids, Cytoxan, plasmapheresis, and hemodialysis. Further workup revealed low C3 at 57, normal C4 and negative MPO Ab, PR3 Ab, ANA, hepatitis panel, anti-GBM Ab, anticardiolipin Ab, SSA Ab, SSB Ab and blood cultures. ADAMTS-13 activity was 43. Renal biopsy showed changes of thrombotic microangiopathy (TMA) with glomerular immunofluorescence staining strongly for C3 compatible with a diagnosis of possible C3 nephropathy (GN). Given his multi-organ involvement, low serum C3, TMA and C3 GN on renal biopsy, and hematologic findings, a diagnosis of aHUS was made. The patient was lost to follow-up so genetic testing and complement blockade therapy could not be initiated.


Diagnosis of aHUS is based on clinical and laboratory findings. Extrarenal manifestations of aHUS are seen in about 20% of cases and often involve the skin, cardiovascular, and central nervous system. To our knowledge, there is only one case reported thus far of aHUS presenting as an acute pulmonary-renal syndrome; this was successfully treated with steroid and plasmapheresis. Although renal involvement with pulmonary hemorrhage is a rare manifestation of aHUS, it should be included in the differential diagnosis of pulmonary-renal syndrome, as early treatment is crucial for the better clinical outcome.