Case Study: How a Distended Bladder Can Alter Mental Status

In cystocerebral syndrome, rapid decompression is the key

By Xavier Jimenez, MD, and Nicole Shirvani, MD

“Cystocerebral syndrome” is recognized as encephalopathy that results from bladder distension and responds rapidly to bladder decompression. The syndrome was first described a quarter century ago in three elderly men who presented with acute urinary retention and altered mental status. We recently published a report of a similar case, recapped below, that underscores the dynamic potential interactions between brain and bladder and aligns with growing evidence that the mechanisms underlying cystocerebral syndrome are more nuanced than conventionally believed.

Case presentation

A 79-year-old man with severe benign prostatic hypertrophy (BPH) and hypertension was admitted to our hospital with altered mental status. He had no psychiatric history. Two weeks earlier, a CT urogram had shown bilateral hydronephrosis and an enlarged prostate, prompting his urologist to consider transurethral resection of the prostate.

According to his wife, in the days before his admission the patient reported dysuria and cloudy urine and had demonstrated increasingly agitated and paranoid behavior for several weeks. This behavior culminated in a flight from his house after stating that his wife aimed to commit him to the “drunk tank.” He was soon found and brought to the emergency room (ER) in an agitated state.

Despite normal vital signs, serological studies showed acute kidney injury, with creatinine levels five times above baseline without uremia. Urinalysis suggested urinary tract infection (UTI), which was later confirmed by culture.

Management and resolution

A five-day empiric antibiotic regimen was started in the ER. Abdominal CT showed constipation, and Foley catheterization produced 1,100 mL of output. Within hours, the patient was observed to be calm, and he required no behavioral intervention.

He was monitored for renal recovery for one week, and psychiatry was consulted during discharge planning. Interview revealed him to be calm, cooperative and free of any focal neuropsychiatric signs or symptoms. He said his wife had exaggerated events of the days leading to his admission, but he acknowledged hypervigilant behaviors and feeling afraid during this period.

The patient scored 21 of 30 on the Montreal Cognitive Assessment, showing deficits in delayed recall and visuospatial functioning, consistent with underlying cognitive impairment. He was diagnosed with resolved delirium secondary to urinary retention.

There’s more to the picture than UTI

Several factors in this case (Figure) are likely to have contributed to the patient’s paranoid psychosis and agitation:

  • Concomitant BPH-mediated urinary retention and constipation that together served to cause bladder outlet obstruction
  • Development of UTI in this setting of acute urinary retention, which likely contributed to encephalopathy
  • The patient’s underlying cognitive impairment, as such impairment is significantly associated with risk of altered mental status



Figure. A pathomechanistic model of cystocerebral syndrome. Reprinted from Shirvani and Jimenez, Journal of the American Geriatrics Society (2015;63:2645-2647).

While UTI has traditionally been considered a sufficient cause of altered mental status, a 2014 systematic literature review called into question a mechanistic role of UTI in encephalopathy. Indeed, it is highly doubtful that a single antibiotic dose could have so swiftly resolved our patient’s agitation in the ER, which prompts us to look to bladder-alleviated sympathetic deactivation (achieved by mechanical decompression in this case) as the likely mechanism of rapid recovery. A role for complementary brain-bladder interaction through increased sympathetic tone secondary to bladder wall distension was first proposed in 1991 and has been bolstered by subsequent animal studies.

Heed the brain-bladder connection

We share this case to increase awareness of the dynamic interaction between brain and bladder and to remind colleagues that cystocerebral syndrome, although rare, can be easily managed by rapid bladder decompression without need for psychiatric interventions.

We also share it to build support for future investigation into bladder-mediated sympathetic activation and related neuropsychiatric phenomena.

Dr. Jimenez is an associate staff physician in Cleveland Clinic’s Center for Behavioral Health. Dr. Shirvani is a psychiatry resident in Cleveland Clinic’s Department of Psychiatry and Psychology.