(069) Dissociative Symptoms in Dialysis: A Presentation of Suspected Dialysis Disequilibrium Syndrome/Delirium

Abstract: Introduction
Dialysis disequilibrium syndrome (DDS) is a rare complication during or following dialysis due to fluid shifts, causing cerebral edema and a variety of neurological symptoms. Symptoms may be mild and self-limited, including headache, restlessness, and confusion; in severe cases, symptoms may present as seizure, coma, or death. (Bhandari, 2020)

Case Presentation
A 43-year-old man with ESRD on dialysis was evaluated by the psychiatry team for behavioral disturbances during dialysis sessions over the past year. The dialysis staff reported his agitation and combative behaviors, including spitting, screaming, and pulling out his lines. He reported “blacking out” during these episodes but remembered his actions afterwards and was apologetic. His wife reported occasional episodes lasting about 30 minutes after dialysis where he was confused and could not recognize her. An EEG and MRI were ordered and were unremarkable. Dialysis disequilibrium syndrome/delirium was suspected. His dialysis sessions were reduced from 4 to 3 hours with improvement in his symptoms. However, after 3 months, he had two more incidents at the end of dialysis sessions, where he was restless and had an episode of attempted theft in the parking lot outside the dialysis center. He was then started on Haldol prior to dialysis and has continued his 3-hour sessions with behavior improvement thus far. Additionally, he has been engaging with Integrated Behavioral Health therapy.

Discussion
Dialysis disequilibrium syndrome (DDS) is a cause of delirium in patients receiving dialysis. It is a diagnosis of exclusion. Two hypotheses have been proposed for the pathogenesis of DDS.
1) The reverse urea effect: Urea naturally exhibits slower diffusion from the CNS into the blood compared to its rapid removal from the serum during dialysis. This disparity creates an osmotic gradient, resulting in water to shift into brain cells and leading to cerebral edema.
2) The idiogenic osmole hypothesis: Idiogenic osmoles are generated by the brain during chronic hyperglycemia and hypernatremia to prevent the formation of an osmotic gradient and protect the brain from fluid losses. Rapid hemodialysis disrupts this equilibrium and creates an osmotic gradient that results in water to move into the brain and causes cerebral edema. (Zepeda-Orozco, 2012; Mistry, 2019)
Treatment of DDS after it has developed includes modifying the dialysis prescription by changing the sodium dialysate bath or engaging the changed prescription on the dialysis machine. (Bhandari, 2020) Prevention of DDS includes avoiding significant osmotic gradients between the blood and brain during dialysis by reducing the clearance, increasing the time over which clearance is performed, and adding osmotically active agents as urea is removed. (Mistry, 2019)

Conclusion
DDS is important to identify in patients who present with confusion and other neurological symptoms on dialysis. Physicians should maintain a high degree of suspicion for DDS, although rare, as early recognition and implementation of prevention strategies can improve outcomes.

References
1. Bhandari B, Komanduri S. Dialysis disequilibrium syndrome. 2020.
2. Zepeda-Orozco D, Quigley R. Dialysis disequilibrium syndrome. Pediatric nephrology. 2012;27:2205-2211.
3. Mistry K. Dialysis disequilibrium syndrome prevention and management. International journal of nephrology and renovascular disease. 2019:69-77.

Presentation Eligibility: This case report was previously presented as a poster at the Creighton University Research Day where students presented research of any topic and field. This case report has been revised to include the updated complete management of his presentation.

Diversity, Equity, and Inclusion: This case report demonstrates the diverse populations that C-L psychiatrists care for. Our patient is a low-income Hispanic male with multiple comorbidities. Additionally, our speaker panel also reflects a diverse population, with a first-generation medical student applying internal medicine and mentored by C-L psychiatry attendings.