Lithium Toxicity and Neurologic Effects: Probable Neuroleptic Malignant Syndrome Resulting from Lithium Toxicity

Abstract

Introduction. We present the case of a patient who developed lithium toxicity with normal therapeutic levels, as a result of pharmacokinetic interaction with Valsartan, and probable Neuroleptic Malignant Syndrome from the ensuing lithium toxicity. Case Presentation. A 59-year old black male with bipolar disorder maintained on lithium and fluphenazine therapy presented with a 2 week history of worsening confusion, tremor, and gait abnormality. He recently had his dose of Valsartan increased. At presentation, patient had signs of autonomic instability, he was confused, dehydrated, and had rigidity of upper extremities. Significant labs on admission were lithium level-1.2, elevated CK-6008, leukocytosis WBC-22, and renal impairment; Creatinine-4.1, BUN-35, HCO3-20.1, and blood glucose 145. CT/MRI brain showed old cerebral infarcts, and there was no evidence of an infective process. Lithium and fluphenazine were discontinued, his lithium levels gradually decreased, and he improved with supportive treatment including rehydration and correction of electrolyte imbalance. Conclusions. This case illustrates that lithium toxicity can occur within therapeutic levels, and the neurotoxic effect of lithium can include Neuroleptic Malignant Syndrome. Clinicians should be aware of the risk associated with drug interactions with lithium.

Leukodystrophy Presenting as Hyperactivity and Bipolarity with Uncommon Adverse Drug Reaction

“…[12] Lithium alone can cause NMS in toxic concentration,[13] but only one case report of NMS caused only by lithium in normal blood levels could be found. [5] Patient in that report was an aged patient with multiple comorbidities and while on multiple medications.…”

Neuroleptic Malignant Syndrome Requiring Neurological Intensive Care Unit Follow-up: Review with Nine Cases

“…NMS daha çok tipik ve yüksek potens antipsikotiklerin (haloperidol gibi) kullanımı ile ilişkili olsa da diğer düşük potens antipsikotikler ve yeni atipik antipsikotiklerle de tanımlanmış olgular mevcuttur (7). Lityum ve diğer antipsikotiklerin beraber kullanımına bağlı olarak ya da karbamazepin gibi antikonvülzanlar ve trisiklik antidepresanların kombinasyonuna bağlı az sayıda olgu da bildirilmiştir (8,9). Bizim olgularımızın hepsinde antipsikotik kullanım öyküsü mevcuttu.…”

“…Otuz iki NMS ve 132 NMS olmayan şizofreni hastasının yer aldığı bir klinik çalışmada, NMS hastalarının çoğunda Dopamin D2 gen polimorfizmi olduğu gösterilmiş, ancak neden bazı dopamin bloke edici ajanlar hastalığa yol açarken, bazılarının yol açmadığı açıklanamamıştır (14). Antipsikotik kullanan hastalarda insidansı %0,01-0,02 arasında değişmektedir (8). Tüm yaş gruplarında görülebilmekle birlikte, yapılan çalışmalar en sık dördüncü ve beşinci dekadlarda görüldüğünü göstermektedir (6).…”

Neuroleptic malignant syndrome associated with amisulpride and lithium: a case report

“…We assume that in our case lithium toxicity and NMS syndrome were induced by combining amisulpride with the lithium therapy. The contribution of comorbid somatic illnesses (gout and hypertension), especially the interaction with the antihypertensive agent valsartan as a risk factor should also be taken into account [22].…”