Hyperammonemic Encephalopathy Secondary to Urinary Tract Infection

Abstract

Hyperammonemic encephalopathy (HE) refers to a clinical condition characterized by abrupt alteration in mental status (AMS) with markedly elevated plasma ammonia levels and frequently results in intractable coma and death. While hepatic cirrhosis is by far the most common etiology for hyperammonemia together with drugs such as valproic acid as well as urea cycle disorders, non-hepatic causes of hyperammonemia are rare and pose a clinical challenge. In this report, we describe a case of HE caused by obstructive urinary tract infection due to urease-producing bacteria in a 69-year-old man with two episodes of obstructive uropathy associated with AMS resolving with treatment with antibiotics and lactulose with normalization of ammonia level. We also provide a review of the literature with emphasis on the recognition of this serious entity of HE in the setting of obstructive uropathy to avoid the possible complications that include intractable coma and high mortality from this potentially treatable disorder.

Ceftriaxone-induced encephalopathy in a patient with a normal renal function

“…We did not measure serum ammonaemia in our patient with normal liver tests, no past hepatic pathology history and absence of asterixis. Rare cases of hyperammonaemia in obstructive urinary tract infections have been described24 25 but were marked by a significant and rapid improvement in the neurological status after bladder catheterisation,24 on the contrary to our patient whose neurological status continued to decline.…”

A Diabetic Patient with Prolonged Hyperammonemia Due to Urinary Tract Infection Caused by Urease-producing Bacteria

“…Many previously reported cases primarily involved urinary voiding difficulties, and improvement was often achieved through the use of bladder catheters or bladder lavage (1,2,5,7,8,10). One patient with a vesicointestinal fistula required percutaneous nephrostomy (6), but cases necessitating retroperitoneal drainage or kidney removal, as in the present patient, were not documented.…”

“…Infection with urease-producing bacteria leads to the breakdown of urea into ammonia in urine. In cases where the urinary tract is obstructed, the bladder and renal pelvis become distended, allowing ammonia to be absorbed directly into the systemic circulation from the surrounding venous plexus, bypassing the liver, and causing hyperammonemia (1).…”

Crisis in the Chest: Acute Chest Syndrome as a Sequela of Tricuspid Valve Endocarditis

“…A meta-analysis by Narayanan et al [ 6 ] found that in patients who had surgical intervention at seven days or less, the odds ratio (OR) of all-cause mortality was 0.61 (95% confidence interval (CI): 0.39 to 0.96, p=0.034), and in those who had surgical intervention within 8-20 days, the OR of mortality was 0.64 (95% CI: 0.48 to 0.86, p=0.003) compared with conservative management. The European Society of Cardiology (ESC) guidelines recommend surgery for right-sided IE in patients receiving appropriate antibiotic therapy who have acute severe tricuspid regurgitation resulting in right ventricular dysfunction, recurrent pulmonary emboli requiring ventilatory support or with large (>20 mm) residual tricuspid vegetations, or involvement of left-sided structures [ 7 , 8 ].…”