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A3358 - Hyperammonemic Encephalopathy: A Late Complication of Ureterosigmoidostomy
Author Block: M. Munawar1, V. Kodadhala2, S. Timberline3, C. Karodeh4, A. Thomas5; 1Internal Medicine, Howard University Hospital, Washington, DC, United States, 2Howard University Hospital, Washington DC, DC, United States, 3Howard University School of Medicine, Washington DC, DC, United States, 4Internal Medicine, Howard University School of Medicine, Washington DC, DC, United States, 5Howard University Hospital, Washington, DC, United States.
Introduction : Ureterosigmoidostomy is one of the antiquated treatments for bladder cancer and congenital bladder anomalies. One of the possible rare complications, years after ureterosigmoidostomy is hyperammonemic encephalopathy. We report a case of 70-year female who underwent ureterosigmoidostomy for bladder cancer and four decades later presented with symptoms of encephalopathy. Case : A 70-year-old female patient presented with altered mental status and was admitted to the ICU, where she was found to have elevated serum ammonia levels. Further investigations ruled out other etiologies of altered mental status, including hepatic and metabolic disorders. Her past medical history was significant for bladder cancer status-post ureterosigmoidostomy which was conducted 38 years ago. Review of her medical records revealed multiple episodes of altered mental status/encephalopathy in the past. Each episode was characterized by confusion, equilibrium difficulty, ataxia and dysarthria. CT head did not reveal any intracranial pathology. EEG was obtained which revealed severe encephalopathy. Patient was intubated for airway protection because of severe encephalopathy/ low Glasgow Coma scale score. Treatment with appropriate bowel regimen including laxatives resulted in improvement of the patient’s neurological condition and she ultimately returned to baseline. Discussion : Ureterosigmoidosotomy is a surgical procedure where the ureters which carry urine from the kidneys, are diverted into the sigmoid colon. Although this procedure is performed seldom now, in clinical practice we may encounter patients who underwent this procedure several decades ago. There are many potential complications secondary to ureterosigmoidostomy, including anastomotic colon cancer, ascending urinary tract infections and stones, hyperchloremic metabolic acidosis, hyperammonemic encephalopathy, electrolyte imbalance, and bone demineralization. Of all these complications, hyperammonemic encephalopathy is exceptionally rare, but if unrecognized, it can be a potentially lethal complication. In our literature review we identified only six case reports with hyperammonemic encephalopathy as a complication after ureterosigmoidostomy, and they were reported to have occurred three decades post-procedure. Because of the late onset and rarity of this complication, it may easily be overlooked, which can lead to more dangerous complications such as encephalopathic coma and death. Conclusion : Hyperammonemic Encephalopathy secondary to ureterosigmoidostomy although rare is a unique complication of this historical procedure. This case highlights the importance of obtaining a thorough medical and surgical history, which often has significant impact on clinical outcomes, morbidity and mortality.