Dementia Dialytica: A Forgotten Condition?

To the Editor, Five decades have passed since the first description of a unique neurological syndrome by Alfrey et al for five patients receiving maintenance hemodialysis in Denver, USA.[1] While only speech abnormalities associated with slow articulation and stuttering were noted on presentation, this subsequently manifested into symptoms of progressive dementia, psychotic behavior, and seizures, leading to the death of all five patients with no effective treatment option available. Electroencephalogram displayed generalized slowing, delta bursts, and spike activity during hospitalization for all five patients. No histopathological abnormalities were concluded on autopsy. This syndrome was eventually coined as "dementia dialytica" in the following year by Vaisrub in a JournaloftheAmericanMedicalAssociation editorial after further reports of similar presentations.[2] Throughout the 1970s, there were numerous publications discussing symptomatic features and potential etiologies of dementia dialytica. While its hallmark characteristics (progressive speech difficulty, altered sensorium, abnormal electroencephalogram findings, seizures, myoclonus, asterixis, apraxia, and psychotic symptoms) were agreed on, no established etiology was decided. There were suggestions that aluminum toxicity was perhaps the instigating factor causing this specific clinical picture, though this has not yet been conclusively determined.[3] Defining a clear histopathological pattern to dementia dialytica is also challenging, as no consistent trends on histopathological abnormalities have been concluded. Nevertheless, it was concurred that treatment options are limited without early kidney transplantation. This was supported by multiple cases, especially one which reported that a patient fully recovered following transplantation.[4] The prognosis was deemed otherwise poor, and most patients died within 6 months of diagnosis. Finding answers to causation, a conclusive histopathological pattern, and treatment in patients presenting with symptoms resembling dementia dialytica remain unestablished up to this day, and original literature focusing on this particular condition waned after the late 1970s. It has since been increasingly recognized that organic brain syndromes in kidney failure are intricate and multi-dimensional, now thought to be primarily attributed to cerebrovascular disease, aging, and hypertension. These factors are commonly associated with maintenance hemodialysis populations. Investigators have determined the dialysis process as a potential instigator for cerebral stunning, and longitudinal studies have established that cognitive function may fluctuate during a single hemodialysis session and in between hemodialysis sessions over time. The evolution of laboratory and imaging techniques allowed for a better understanding of the pathogenesis of neurological impairment associated with hemodialysis. Identification of structural brain changes, including silent cerebral infarctions, white matter hyperintensities, and cerebral atrophy, is well-described in hemodialysis-receiving patients, and recently shown to portend all cerebrovascular events, including cognitive impairment and executive dysfunction.[5] In our day-to-day clinical practice within the dialysis setting, we have faced cases which resemble the characteristics of dementia dialytica, but confidently confirming a formal diagnosis have proven difficult because there remains a paucity of validated knowledge and official guidance to define the boundaries of this condition. Considering the current advances, are we better situated now to finally evaluate the pathogenesis of dementia dialytica and determine improved treatment options? We hope through this letter, we may be able to raise awareness of this enigmatic and bizarre condition and reignite research efforts to address unanswered questions surrounding it. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.