Neurological sequelae of end stage renal disease (ESRD)

Antipsychotics and hemodialysis: A systematic review

OBJECTIVE

Antipsychotics play a crucial role in the management of behavioral problems in patients undergoing hemodialysis. Oral and injectable antipsychotics are routinely prescribed to control emergent delirium or exacerbation of previous psychiatric symptoms. However scanty literature is available on the pharmacokinetics of antipsychotics in such patients. Avoiding amisulpride and warning against increasing the dosage in renal failure is the only recommendation by drug manufacturers and clinical guidelines. Hemodialysis affects the volume of distribution (V_d) and blood levels of antipsychotics in a complex manner. It is hence difficult to equate data on renal failure with hemodialysis to reliably predict the treatment response.

METHOD

We systematically analyzed online data from 1981 to 2019 on the use of antipsychotics in hemodialysis. The outcome was defined as the safety and efficacy of AP, measured in terms of adverse effects and relapse of existing or new onset of behavioral symptoms in Hemodialysis.

RESULTS

The data from 182 studies revealed that only 14 case reports and 1 case series met the review criteria. Oral Risperidone, Clozapine, Aripiprazole, Ziprasidone, Haloperidol, and Long-acting Risperidone, Flupenthixol, and Paliperidone were the antipsychotics studied in terms of pharmacokinetics during hemodialysis. AP levels in the blood were found to be unaffected in two studies during HD while the other two studies recommended scheduling of AP regimen w.r.t HD session. Six reports mentioned exacerbation of pre-existing psychiatric ailments in patients undergoing HD, the most common being schizophrenia.

CONCLUSION

Findings of the review reveals modest evidence favoring multiple dosing regimens of oral aripiprazole, ziprasidone, olanzapine, and risperidone. Long-acting risperidone and paliperidone are well tolerated and half of the conventional dose may be effective in the case of paliperidone. Though CYP-3A4 remains relatively and transiently unaltered during hemodialysis, none of the antipsychotics are compromised in HD. While selecting an AP during HD, one has to consider the protein binding, clearance by dialysis, duration of an HD session, route of administration of AP, and impaired bowel absorption in HD.

Hemorrhagic Stroke in Chronic Dialysis Patients

AIMS

This study was designed to retrospectively investigate the clinical profiles, disease course and management of hemorrhagic stroke in chronic dialysis patients. We emphasized on the factors affecting the prognosis.

PATIENTS AND METHODS

We retrospectively studied (January 1991-June 1999) the chronic dialysis patients who were admitted to our facility with a diagnosis of acute hemorrhagic stroke. The medical results were reviewed in detail and the clinical characteristics, laboratory data and management records of each individual were collected for analysis.

RESULTS

There were 16 patients analyzed in total, 9 males and 7 females. The average age was 59.4+/-13.3 years old. Before admission, 14 patients received chronic hemodialysis (HD) and two patients peritoneal dialysis (PD). The co-morbidities included hypertension (16/16), Diabetes Mellitus (DM) (9/16), previous cerebrovascular accidents (9/16) and hyperlipidemia (5/16). The locations of cerebral hemorrhage (CH) were: the putamen (6/16), brain stem (3/16), thalamus (3/16) and others (4/16). Among the 14 HD patients, 8 remained on HD after onset of CH, while 6 switched to PD. Those who received PD before their development of CH continued to perform PD. The overall mortality was 44% (7/16). One of the 8 patients who continued on HD died (mortality 12.5%). Among the 8 patients who received PD, 6 died (mortality 75%). Two patients who underwent surgical intervention also passed away. The major cause of death was neurological deterioration. The interval between the onset of CH and death was short (15+/-13 days, range 2-39 days).

CONCLUSION

The overall prognosis of CH in the chronic dialysis population is poor. Patients with lower hemoglobin levels upon presentation and those performing PD after CH may have even worse prognosis.

Spontaneous posterior fossa hemorrhage associated with low-molecular weight heparin in an adolescent recently diagnosed with posterior reversible encephalopathy syndrome: case report and review of the literature

BACKGROUND

Posterior reversible encephalopathy syndrome (PRES) constitutes a well-described clinical entity, classically entailing characteristic edematous lesions on imaging studies in a patient with altered mental status, visual disturbances, headache, and seizures. PRES is reversible in the vast majority of cases, although progression to ischemia and hemorrhage has been documented.

METHODS

We report a case of a 16-year-old male with chronic renal failure who developed PRES during a hypertensive crisis. The hypertension was successfully managed and PRES-associated symptomatology showed complete regression. However, approximately 2 months later, the patient returned with a spontaneous posterior fossa hemorrhage. Two weeks before this second admission, treatment with low-molecular weight heparin had been initiated. The patient finally succumbed, despite surgical evacuation. The pertinent literature is reviewed.

CONCLUSION

We suggest that the administration of low-molecular weight heparin in the setting of recent PRES might increase the risk for the development of intracranial hemorrhage.

N-acetylaspartate in the vertebrate brain: metabolism and function

N-Acetyl-L-aspartate (NAA) is an amino acid that is present in the vertebrate brain. Its concentration is one of the highest of all free amino acids and, although NAA is synthesized and stored primarily in neurons, it cannot be hydrolyzed in these cells. Furthermore, neuronal NAA is dynamic and turns over more than once each day by virtue of its continuous efflux, in a regulated intercompartmental cycling via extracellular fluids, between neurons and a second compartment in oligodendrocytes. The metabolism of NAA, between its anabolic compartment in neurons and its catabolic compartment in oligodendrocytes, and its possible physiological role in the brain has been the subject of much speculation. There are two human inborn errors in metabolism of NAA. One is Canavan disease (CD), in which there is a buildup of NAA (hyperacetylaspartia) and associated spongiform leukodystrophy, caused by a lack of aspartoacylase activity. The other is a singular human case of lack of NAA (hypoacetylaspartia), where the enzyme that synthesizes NAA is apparently absent. There are two animal models currently available for studies of CD. One is a rat with a natural deletion of the catabolic enzyme, and the other a gene knockout mouse. In addition to the presence of NAA in neurons, its prominence in 1H nuclear magnetic resonance spectroscopic studies has led to its wide use in diagnostic human medicine as both an indicator of brain pathology and of disease progression in a variety of CNS diseases. In this review, various hypotheses regarding the metabolism of NAA and its possible role in the CNS are evaluated. Based on this analysis, it is concluded that although NAA may have several functions in the CNS, an important role of the NAA intercompartmental system is osmoregulatory, and in this role it may be the primary mechanism for the removal of intracellular water, against a water gradient, from myelinated neurons.

Involvement of voltage- and ligand-gated Ca2+ channels in the neuroexcitatory and synergistic effects of putative uremic neurotoxins

BACKGROUND

Renal failure has been viewed as a state of cellular calcium toxicity due to the retention of small fast-acting molecules. We have tested this hypothesis and identified potentially neuroexcitatory compounds among a number of putative uremic neurotoxins by examining the acute in vitro effects of these compounds on cultured central neurons. The in vitro neuroexcitatory and synergistic effects of guanidinosuccinate and spermine were also examined in vivo.

METHODS

The acute effects of 17 candidate uremic neurotoxins on murine spinal cord neurons in primary dissociated cell culture were investigated using the tight-seal whole-cell recording technique. The compounds studied comprised low-molecular-weight solutes like urea, indoles, guanidino compounds, polyamines, purines and phenoles, homocysteine, orotate, and myoinositol. Currents evoked by these compounds were further examined using various ligand- and voltage-gated ion channel blockers. The acute in vivo effects of guanidinosuccinate and spermine were behaviorally assessed following their injection in mice.

RESULTS

It was shown that 3-indoxyl sulfate, guanidinosuccinate, spermine, and phenol evoked significant whole-cell currents. Inward whole-cell current evoked by 3-indoxyl sulfate was not blocked by any of the applied ligand- or voltage-gated ion channel blockers, and the compound appeared to influence miscellaneous membrane ionic conductances, probably involving voltage-gated Ca2+ channels as well. Phenol-evoked outward whole-cell currents were at least partly due to the activation of voltage-gated K+ channels, but may also involve a variety of other ionic conductances. On the other hand, inward whole-cell currents evoked by guanidinosuccinate and spermine were shown to be due to specific interaction with voltage- and ligand-gated Ca2+ channels. Guanidinosuccinate-evoked current was caused by activation of N-methyl-d-aspartate (NMDA) receptor-associated ion channels. Low (micromol/L) concentrations of spermine potentiated guanidinosuccinate-evoked current through the action of spermine on the polyamine binding site of the NMDA receptor complex, whereas current evoked by high (mmol/L) concentrations of spermine alone involved direct activation of voltage-gated Ca2+ channels. Finally, intracerebroventricular administration of 0.25 micromol/L spermine potentiated clonic convulsions induced by guanidinosuccinate. These neuroexcitatory and synergistic effects of guanidinosuccinate and spermine could take place at pathophysiologic concentrations.

CONCLUSION

The observed in vitro and in vivo effects of uremic retention solutes suggest that the identified compounds could play a significant role in uremic pathophysiology. Some of the compounds tested displayed in vitro and in vivo neuroexcitatory effects that were mediated by ligand- and voltage-gated Ca2+ channels. The findings suggest a mechanism for the involvement of calcium toxicity in the central nervous system complications in renal failure with particular reference to guanidinosuccinate and spermine.

Central nervous dysfunction in uremia

The mechanisms of central nervous system dysfunction in uremia are multifactorial and only partially characterized. Studies using sealed presynaptic nerve terminals (synaptosomes) for in vitro ion transport and metabolism of neurotransmitter in chronic renal failure (CRF) neuronal cell culture and in vivo brain structure microdialysis generated significant new information. An increase in total calcium content of the cerebral cortex accompanied by increased levels of cytosolic calcium ([Ca(2+)]i) in synaptosomes are common findings in rats with CRF. Mechanisms leading to the increase in [Ca(2+)]i include increased calcium uptake mediated by parathyroid hormone and decreased activity of Na(+),K(+)-adenosine triphosphatase (ATPase) and Ca(2+)-ATPase of synaptosomes in CRF rats. Moreover, these synaptosomes respond inappropriately to depolarization, which can impair neurotransmitter metabolism. Brain gamma-aminobutyric acid content, norepinephrine, and acetylcholine release uptake and degradation are affected by uremia. These may lead to certain somatic, behavioral, and motor dysfunctions in uremia. Many derangements of the central nervous system in uremia appear to be mediated by secondary hyperparathyroidism of CRF because parathyroidectomy of animals with CRF prevented the increase in basal levels of [Ca(2+)]i and derangements in neurotransmitter metabolism. The role of other neurotoxins, such as guanidinosuccinic acid, are also reviewed.

The Howard University Hospital Transplant and Dialysis Support Group: twenty years and going strong

This article discusses group therapy as part of a multidisciplinary approach to the management of the various psychological and physical rehabilitation concerns posed by kidney and liver transplant candidates and recipients at Howard University Hospital in Washington, DC. The group's history, format, intervention foci, and roles of clinicians and patients attending the group are described and evaluated. Given the relative paucity of research literature in this area, the authors offer recommendations for empirical evaluation of the benefits of multidisciplinary group psychotherapy in ameliorating physical and emotional suffering and prolonging life among transplant patients.

Association between renal function and cognition in childhood chronic renal failure

Forty-five children with renal failure who were either being medically managed, receiving dialysis (hemodialysis or continuous ambulatory peritoneal dialysis) therapy or who had received successful kidney transplants were longitudinally examined on multiple neuropsychological measures. A variety of medical parameters was also obtained at each time of testing. The neuropsychological variables were correlated with the medical variables using the repeated measures regression analysis method. There were associations between levels of renal function, short-term memory and list learning. Other neuropsychological variables did not in general correlate with the medical parameters consistently for all ages at the time of initial testing. Verbal performance decreased with increasing duration of renal failure in 6- to 11-year-olds and immediate recall decreased with increasing percentile rank of systolic blood pressure in 16- to 18-year-olds.

Neuropsychological patterns in uremia

Administered the Halstead-Reitan Battery (HRB) of neuropsychological tests to 24 patients with advanced renal failure, 24 patients with neurological disorders, and 24 patients with medical and/or non-psychotic psychiatric conditions in order to assess the effects of uremic encephalopathy on human neuropsychological functioning. The groups did not differ significantly in age, education, verbal intelligence, or level of affective disturbance. Results indicated that the uremic and neurological groups were equal in overall level of neuropsychological impairment and that both were significantly more impaired than the medical-psychiatric group. However, the uremic group showed a pattern of deficits that was qualitatively different from both the neurological and medical-psychiatric groups. Results were discussed with reference to selective cortical dysfunctions in uremia and contrasted with earlier studies that did not consider differential sparing of abilities in renal patients.

A short-term follow-up of patients with depressive disorder on entry into home dialysis training

Fifteen (18%) of 83 patients entering home hemodialysis training were found to suffer major depressive disorder diagnosed by rigorous clinical criteria. The diagnosis of depressive disorder was associated with a diagnosis of polycystic kidney disease. It was not, however, associated with past or family history of affective illness. Neither intellectual impairment nor chemical uremia were more pronounced in the patients with depressive disorder than in the patients without depressive disorder. Depressive symptoms almost invariably remitted during home dialysis training and had no apparent influence on outcome on the basis of a short-term (3-month) follow-up.