This is a 66-year-old diabetic woman with a history of hepatitis C virus of post-transfusion aetiology.
In January 2006 she presented with a persistent voiding syndrome which did not respond to treatment and she underwent cystoscopy with subsequent TUR. She was diagnosed with pTa G3 bladder carcinoma and started treatment with intravesical BCG.
The follow-up TUR at the end of BCG treatment detected the presence of multiple foci of carcinoma in the bladder, confirming the diagnosis of urothelial carcinoma invading the muscular layer (pT2 G3).
In July 2006 she underwent a radical cystectomy with urinary diversion by means of a Mainz II type ureterosigmoidostomy. The pathological anatomy showed a high-grade urothelial carcinoma with invasion of the muscular layer and involvement of one of the resected lymph nodes, a pT2a N1. No distant metastases were detected.
Two weeks after the operation, he presented with disorientation and a tendency to sleep in the context of a condition compatible with a urinary tract infection. After 24 hours of observation, intravenous hydration and antibiotic therapy, she recovered and was discharged on oral antibiotics.
Ten days later she returned to the hospital with the appearance of dyspraxia, a tendency to sleep, incoherent speech and drowsiness. During the episode she also presented a febrile peak of 38.5ºC. Biochemistry and haemogram were normal (no leukocytosis or neutrophilia). An abdominal ultrasound scan identified moderate bilateral hydronephrosis and a CT scan of the brain was normal.
During her admission, and after initiation of broad-spectrum antibiotic treatment and fluid therapy, the confusional picture gradually resolved until complete recovery.
A few days later, the patient again presented cognitive deterioration. On this occasion, the onset of the central symptoms had been similar, with dyspraxia, sudden difficulty in performing daily tasks, somnolence and obtundation, but on this occasion she came to the hospital in a coma, with a Glasgow Glasgow Glasgow score of 8.
Laboratory tests showed only moderate hyperglycaemia and slightly elevated transaminases.
An electroencephalogram showed slow waves over areas of both hemispheres, characteristic findings of metabolic encephalopathy. A CT scan of the brain showed no structural abnormalities. Similar to the previous admission, after several days in hospital with supportive fluid therapy and absolute diet, the patient experienced a progressive improvement with complete clinical recovery.
Three weeks later, the patient again noticed symptoms of dyspraxia and a tendency to sleep with progressive onset. She went to the emergency department where she was evaluated without finding any alterations in the examination or in the analytical or imaging tests, so she was sent home; there was no fever or any other symptoms suggestive of infection. Twenty-four hours later, she presented with a severely altered level of consciousness with a Glasgow score of 6.
On this occasion, the patient had started a first cycle of adjuvant chemotherapy 15 days earlier, with taxol 175 mg/m2 and carboplatin AUC 5. All other electrolyte parameters, including calcaemia, were strictly normal. Venous blood gas analysis showed a pH of 7.44. Brain CT and chest X-ray were normal.
Given the presence of repeated episodes of confusional syndrome of probable metabolic cause, all within 3 months of the cystectomy, it was considered that this could be a metabolic complication of the shunt. After ruling out metabolic acidosis, it was decided to request blood ammonium levels, which showed an ammonaemia of 400 micrograms/dl (normal between 17-80).
Given the diagnosis of hyperammonaemic encephalopathy of non-hepatic cause, fluid therapy, absolute diet, lactulose enemas were started and, given the clinical severity, haemodialysis was started. After 3 haemodialysis sessions, the patient experienced a neurological recovery parallel to the correction of ammonium levels, which decreased to normal.
Subsequently, the ureterosigmoidostomy was surgically converted to an ileal conduit. Currently the patient continues with adjuvant chemotherapy treatment and has not had any new confusional episodes.