Abstract: FR-PO653
Hemodialysis for Urea Cycle Disorder Associated Hyperammonemia - Does It Have a Role?
Session Information
- Trainee Case Reports - IV
October 26, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Trainee Case Reports
- 701 Dialysis: Hemodialysis and Frequent Dialysis
Authors
- Delgado Garrastegui, Angel Fernando, LSU Health Shreveport, Shreveport, Louisiana, United States
- Velazquez perez, Agustin G., LSU health shreveport, Shreveport, Louisiana, United States
- Cheeti, Apoorva, Willis-Knighton Health System, Shreveport, Alabama, United States
- Sachdeva, Bharat, Lousiana State University - Shreveport, Amritsar, India
- Singh, Neeraj, LSU Health Sciences Center, Shreveport, Louisiana, United States
Introduction
Hemodialysis for hyperammonemia is rarely performed. We report a patient who presented with acute encephalopathy, nausea and vomiting associated with elevated levels of serum ammonia and normal hepatic workup and responded only to hemodialysis.
Case Description
A 20 year old Caucasian male with no significant past medical history presented with nausea, vomiting and altered mental status of one day duration. On admission, his vitals were stable and examination was unremarkable except for disorientation. Laboratory work-up revealed normal CBC and BMP and liver function tests except for elevated serum ammonia at 144 mmol/L (normal11-32mmol/L): Head CT, EEG and CSF fluid analysis were negative. Further liver work up including hepatitis panel, HIV screen, alfa-feto-protein, calcinoembrionic antigen, smooth muscle ab, alpha-1 antitrypsin, anti-mitochondrial ab, antinuclear ab, ceruloplasmin level, hemochromatosis panel, liver ultrasound and a liver biopsy was normal. On admission, patient was started on intravenous fluids, vitamin B12, lactulose, rifaximin and protein restriction, but failed to respond and serum ammonia levels trended up to 275 mmol/L on day 3. He was initiated on hemodialysis and underwent a total of 2 dialysis sessions with reduction in ammonia levels to <9umol/L and improvement in mentation by day 5. The urine organic acid gas chromatography test showed highly elevated orotic and uracil levels suggesitive of a urea cycle defect, possibly OTC (ornithine transcarbamylase deficiency), citrullinemia, argininosuccinic aciduria, argininemia or Hyperammoninemia-Hyperornithinemia-Homocitrullinuria syndrome. Genetic testing was negative for the most common mutations but did not rule out a urea cycle defect. The patient was discharged on L carnitine, lactulose and a low protein diet and has not had a recurrent episode of hyperammonemia till last follow-up.
Discussion
Serum Ammonia is a small molecule, with a molecular weight less than that of urea and as such its clearance by a dialyzer membrane is greater than the clearance rate for urea. Hemodialysis can be effectively utilized to treat hyperammonemia associated with urea cycle defect in medically refractory cases.