The use of lithium levels in the emergency department

Insights into the neurobiology of suicidality: explicating the role of glutamatergic systems through the lens of ketamine

Suicidality is a prevalent mental health condition, and managing suicidal patients is one of the most challenging tasks for health care professionals due to the lack of rapid-acting, effective psychopharmacological treatment options. According to the literature, suicide has neurobiological underpinnings that are not fully understood, and current treatments for suicidal tendencies have considerable limitations. To treat suicidality and prevent suicide, new treatments are required; to achieve this, the neurobiological processes underlying suicidal behavior must be thoroughly investigated. Although multiple neurotransmitter systems, particularly serotonergic systems, have been studied in the past, less has been reported in relation to disruptions in glutamatergic neurotransmission, neuronal plasticity, and neurogenesis that result from stress-related abnormalities of the hypothalamic-pituitary-adrenal system. Informed by the literature, which reports robust antisuicidal and antidepressive properties of subanaesthetic doses of ketamine, this review aims to provide an examination of the neurobiology of suicidality (and relevant mood disorders) with implications of pertinent animal, clinical, and postmortem studies. We discuss dysfunctions in the glutamatergic system, which may play a role in the neuropathology of suicidality and the role of ketamine in restoring synaptic connectivity at the molecular levels.

Accumulation of Lithium in the Hippocampus of Patients With Bipolar Disorder: A Lithium-7 Magnetic Resonance Imaging Study at 7 Tesla

BACKGROUND

Lithium (Li) is a first-line treatment for bipolar disorder (BD). To study its cerebral distribution and association with plasma concentrations, we used ⁷Li magnetic resonance imaging at 7T in euthymic patients with BD treated with Li carbonate for at least 2 years.

METHODS

Three-dimensional ⁷Li magnetic resonance imaging scans (N = 21) were acquired with an ultra-short echo-time sequence using a non-Cartesian k-space sampling scheme. Lithium concentrations ([Li]) were estimated using a phantom replacement approach accounting for differential T₁ and T₂ relaxation effects. In addition to the determination of mean regional [Li] from 7 broad anatomical areas, voxel- and parcellation-based group analyses were conducted for the first time for ⁷Li magnetic resonance imaging.

RESULTS

Using unprecedented spatial sensitivity and specificity, we were able to confirm the heterogeneity of the brain Li distribution and its interindividual variability, as well as the strong correlation between plasma and average brain [Li] ([Li]_B ≈ 0.40 × [Li]_P, R = .74). Remarkably, our statistical analysis led to the identification of a well-defined and significant cluster corresponding closely to the left hippocampus for which high Li content was displayed consistently across our cohort.

CONCLUSIONS

This observation could be of interest considering 1) the major role of the hippocampus in emotion processing and regulation, 2) the consistent atrophy of the hippocampus in untreated patients with BD, and 3) the normalization effect of Li on gray matter volumes. This study paves the way for the elucidation of the relationship between Li cerebral distribution and its therapeutic response, notably in newly diagnosed patients with BD.

Lithium bioaccumulation in Lentinus crinitus mycelial biomass as a potential functional food

Lentinus crinitus is an important basidiomycete consumed by ethnic groups from the Amazon, commonly found in decomposing trees with high lignolytic and antioxidant activities. Lithium is a mood stabilizer, antiepileptic, antipsychotic, and antidepressant used in clinical practice. This study aimed to evaluate L. crinitus mycelial biomass bioaccumulated with lithium in liquid cultivation medium. The malt extract medium was added from zero to 100 mg L^-1 lithium from two lithium sources (Li₂CO₃ and LiCl). The maximum mycelial biomass production was 7218.89 mg L^-1 in the culture medium added with 5 mg L^-1 lithium from LiCl. The highest lithium concentration in the mycelial biomass was of 574.72 μg g^-1 produced in the culture medium with 25 mg L^-1 lithium from Li₂CO₃. Pearson's correlation showed that Li₂CO₃ reduces the mycelial biomass and increases lithium bioaccumulation. The maximum translocated lithium from cultivation medium to mycelial biomass was up to 19 or 28% with LiCl or Li₂CO₃, respectively. Therefore, although Li₂CO₃ presents greater inhibition on the mycelial biomass production, it promoted greater lithium bioaccumulation in L. crinitus mycelial biomass and resulted in greater yield of lithium translocation. The equivalent daily dose of lithium for psychiatric treatment, without bioavailability studies, could be reached with 97.4 g lithium-enriched mycelial biomass and, based in the literature, for reduction of violence and criminality rates the amount could be reached with 0.24-0.58 mg. Thus, the development of lithium-enriched mycelial biomass could be an alternative functional food.

Is lithium biologically an important or toxic element to living organisms? An overview

Industrialized world is exposing living organisms to different chemicals and metals such as lithium (Li). Due to their use in common household items to industrial applications, it is imperative to examine their bioavailability. Lithium belongs to the group IA and also has wider uses such as in batteries, air conditioners to atomic reactors. Lithium occurs naturally in soil and water, mostly at low concentrations, and enters the food chain. It is not one of the essential minerals though various studies indicate that low levels of Li have beneficial effects on living organisms, whereas high levels expose them to toxicity and related detrimental effects. This review suggests that Li could be biologically important to living organism depending upon its concentration/exposure. Little is known about its biological importance and molecular understanding of its accumulation and mode of action, which might have future implications for Li's long-term effects on living organisms.

Use of the Clinical Laboratory in Psychiatric Practice

In this review, the authors address the general principles of prescribing psychiatric medications and discuss how the clinical laboratory can be used to guide prescribing practices. Treatment considerations in different settings and for different medications are discussed. Because the clinical laboratory is advancing in its technology, so should the clinician's knowledge of how to use the clinical laboratory. The authors propose recommendations and a simple algorithm for how to use medication levels in blood and other fluids to guide care in medications without well-defined therapeutic windows.

Polypharmacy May Be the Cause of Acute Lithium Intoxication at the Second Day of Treatment

Lithium is frequently used as a mood stabilizer in patients with mood disorders. Lithium has a narrow therapeutic index and high toxicity. Predisposing factors for intoxication are advanced age, diet disturbances, comorbid medical conditions affecting heart, kidneys or central nervous system and polypharmacy.

CASE REPORT

Here we present a case of a 74-year-old woman with a history of Parkinson's disease, hypertension and bipolar disorder. She was using quetiapine, valsartan with hydrochlorothiazide and levodopa with carbidopa. She presented with altered mental status and muscle rigidity. The patient was admitted with acute lithium intoxication after her second dose of treatment. Blood lithium level increased to 3.58 mEq/L. The woman was hospitalized in the Internal Medicine Intensive Care Unit. With hydration, her symptoms resolved and her lithium level returned to normal after 118 hours.

CONCLUSIONS

Prescribing physicians and emergency room physicians should be aware of conditions which may cause a decreased threshold for intoxication.

The Syndrome of Irreversible Lithium-Effectuated Neurotoxicity (SILENT): one-year follow-up of a single case

In this article, we report the case history of a 44-year-old female patient with bipolar disorder who developed the so-called Syndrome of Irreversible Lithium-Effectuated Neurotoxicity (SILENT). A detailed description of our patient's neurologic status is provided at baseline (i.e. during lithium intoxication) and after one year of follow-up, confirming the persistency of cerebellar signs and symptoms. Although rare, our report - which shows a severe and disabling form of SILENT - underscores the need to perform a strict control of the putative risk factors argued to be associated with the development of this syndrome. In our case, the presence of fever and the administration of multiple doses of antipsychotics may have contributed to the poor outcome exhibited by the patient.

Toxicity of lithium to humans and the environment--a literature review

Lithium concentrations in the surface and underground waters may be higher than general environment in places where lithium-rich brines and minerals occur, and in places where lithium batteries are disposed of. This review has indicated that lithium is not expected to bioaccumulate and its human and environmental toxicity are low. Lithium is not a dietary mineral for plants but it does stimulate plant growth. Large doses of lithium (up to 10 mg/L in serum) are given to patients with bipolar disorder. At 10 mg/L of blood, a person is mildly lithium poisoned. At 15 mg/L they experience confusion and speech impairment, and at 20 mg/L Li there is a risk of death. A provisional recommended daily intake of 14.3 microg/kg body weight lithium for an adult has been suggested.

Lithium toxicity from an Internet dietary supplement

INTRODUCTION

The widespread availability of medications and herbal products on the Internet has increased the potential for poisonings. We are reporting a case of mild, acute lithium toxicity occurring after the intentional misuse of a lithium-containing "dietary supplement" (Find Serenity Now) obtained over the Internet.

CASE REPORT

An 18-year-old woman presented to our emergency department (ED) after ingesting 18 tablets of Find Serenity Now; each tablet contained, according to the listing, 120 mg of lithium orotate [3.83 mg of elemental lithium per 100 mg of (organic) lithium orotate compared to 18.8 mg of elemental lithium per 100 mg of (inorganic) lithium carbonate]. The patient complained of nausea and reported one episode of emesis. Her examination revealed normal vital signs. The only finding was a mild tremor without rigidity. Almost 90 minutes after the ingestion, her serum lithium level was 0.31 mEq/L, a urine drug screen was negative, and an electrocardiogram (ECG) showed a normal sinus rhythm. The patient received intravenous fluids and an anti-emetic; one hour later, her repeat serum lithium level was 0.40 mEq/L. After 3 hours of observation, nausea and tremor were resolved, and she was subsequently transferred to a psychiatric hospital for further care. Prior human and animal data have shown similar pharmacokinetics and shared clinical effects of these lithium salts.

DISCUSSION

Over-the-Internet dietary supplements may contain ingredients capable of causing toxicity in overdose. Chronic lithium toxicity from ingestion of this product is also of theoretical concern.

Unrecognized delayed toxic lithium peak concentration in an acute poisoning with sustained release lithium product

A 32-year-old female with a history of bipolar disorder was admitted after taking approximately 16 g of an extended-release lithium carbonate formulation in an attempted suicide. Five hours after consumption, the lithium serum level was 3.2 mEq/L. Fourteen hours after consumption, the lithium level was 5.1 mEq/L and the patient was asymptomatic. Due to a level > 4 mEq/L, the patient was transferred to a renal medicine service for hemodialysis. The lithium concentration 6 hours after the hemodialysis was 2.54 mEq/L. Thirty seven hours after the consumption (15 hours after hemodialysis), lithium levels increased up to 6.09 mEq/L. A second hemodialysis session was performed, which successfully reduced the serum lithium concentration to 1.86 mEq/L. Lithium levels 85 hours after the consumption were 0.61 mEq/L and the patient was transferred to the Psychiatry Department. Unrecognized delayed toxic peak lithium concentration may appear in an acute poisoning with a sustained release lithium product. Therefore, patients presenting with acute intoxication with extended release formulations should be managed with caution, and continued drug monitoring is suggested.

Delirium and extrapyramidal symptoms due to a lithium-olanzapine combination therapy: a case report

We report an elderly patient who developed severe delirium and extrapyramidal signs after initiation of lithium-olanzapine combination. On hospital admission, serum levels of lithium were found to be 3.0 mM/L which were far above toxic level. Immediate discontinuation of both drugs resulted in complete resolution of most of the symptoms except for perioral dyskinesia which persisted for three more months. We critically discussed the differential diagnosis of lithium intoxication and assessed confounding factors which induce delirium and extrapyramidal signs related with combination therapy of lithium and olanzapine.

Lithium toxicity: an iatrogenic problem in susceptible individuals

OBJECTIVE

Lithium toxicity, manifesting primarily as neurotoxicity, is a significant health problem and is primarily iatrogenic in nature. Despite 50 years of medical experience with lithium, factors contributing to the development of severe neurotoxicity remain poorly documented. We hypothesized that severe neurotoxicity represents the most clinically significant manifestation of lithium toxicity. We proposed that this occurs primarily in the context of chronic therapeutic administration ('chronic poisoning'), rather than in the context of an overdose. Furthermore we hypothesized that patients who developed chronic poisoning did so in the presence of identifiable factors which predictably impair lithium clearance.

METHOD

A retrospective analysis of 97 cases of lithium poisoning, treated at a regional centre over a 13-year period was performed. Demographic data and factors considered likely to relate to the risk of developing lithium toxicity were recorded. Patients were classified according to mode of poisoning (acute, acute on chronic, or chronic) and according to severity of neurotoxicity (nil, mild, moderate, severe). The risk of developing severe neurotoxicity as a result of each mode of poisoning was assessed. The association between various risk factors and the development of chronic poisoning was assessed using a logistic regression model.

RESULTS

Twenty-eight cases were rated as suffering severe neurotoxicity; in 26 this developed in the context of chronic poisoning and in two in the context of acute on chronic poisoning. All patients who developed severe neurotoxicity had at least one putative risk factor present, regardless of mode of poisoning. Length of stay was significantly longer for cases with severe neurotoxicity compared to those without severe neurotoxicity (12 vs. 2 days, P < 0.001). Peak serum lithium concentrations were significantly higher in cases with severe neurotoxicity compared to those without (2.3 vs. 1.6 mmol/L, P = 0.02). Patients presenting with chronic poisoning had a substantially higher risk of severe neurotoxicity than those presenting after an overdose of lithium (Odds Ratio [OR] 136, 95% CI 23-1300). A logistic regression model showed three factors contributed independently to the risk of chronic poisoning. These were: nephrogenic diabetes insipidus (adjusted OR 26.96, 95% CI 2.89-251.94), age over 50 years (adjusted OR 6.20, 95% CI 1.36-28.32) and thyroid dysfunction (adjusted OR 9.30, 95% CI 1.36-63.66). A fourth factor, baseline endogenous creatinine clearance below normal limits, was significant at the P = 0.05 level (adjusted OR 6.49, 95% CI 0.98-43.01). Hyperparathyroidism was noted in three cases of chronic poisoning suffering severe neurotoxicity.

CONCLUSION

Severe lithium neurotoxicity occurs almost exclusively in the context of chronic therapeutic administration of lithium, and rarely results from acute ingestion of lithium, even in patients currently taking lithium. As such it is an iatrogenic illness, occurring in patients who have identifiable clinical risk factors: nephrogenic diabetes insipidus, older age, abnormal thyroid function and impaired renal function. Although administration of drugs which impair lithium clearance appeared to contribute minimally to chronic lithium poisoning in the absence of other factors, these drugs may well 'uncover' the predisposing risk factors and certainly should not be considered safe to use as a consequence of this study. The serious morbidity suffered by lithium toxic patients, and the cost to society due to long hospital stays, might be reduced by careful prescribing, vigilant monitoring and awareness of these factors, as they develop in otherwise stable patients. Review of existing therapeutic guidelines may be warranted.