Aciclovir
- PDF / 153,205 Bytes
- 1 Pages / 595.245 x 841.846 pts (A4) Page_size
- 89 Downloads / 140 Views
1 OS
Aciclovir toxicity and neurotoxicity in the form of encephalopathy, secondary to aciclovir overdose due to inappropriate dosing of aciclovir (dose prescription error): case report A 68-year-old man developed aciclovir toxicity and neurotoxicity in the form of encephalopathy, secondary to aciclovir overdose due to inappropriate dosing of aciclovir (dose prescribing error) for varicella-zoster virus (VZV) infection. The man, who had the end-stage renal disease (ESRD), was diagnosed with cutaneous zoster reactivation. He subsequently started receiving oral aciclovir [acyclovir] 800mg five times daily. Four days after initiation of aciclovir, he exhibited worsening of confusion, agitation, speech difficulty and hallucinations which lead to admission. His medical history was significant for ESRD, secondary hyperparathyroidism, anaemia due to chronic renal disease, type 2 diabetes mellitus and hypertension. His concomitant medications included amlodipine, aspirin, metoprolol-succinate and insulin-suspension-isophane [insulin NPH]. Aciclovir was the only new medication which started 4 days prior to admission. His outpatient dialysis frequency was noted to be three times weekly. Upon physical examination, he was found agitated and was oriented only to self. Subsequent skin examination showed a right-sided rash with erythematous papules with vesicles along the T9 dermatome. He was unable to follow commands for testing cranial nerves, strength or coordination during neurologic examination. Additionally, he exhibited dysarthric speech. The urinalysis, brain MRI scan and chest x-ray were noted to be normal. The electroencephalogram revealed diffuse slowing and disorganisation, consistent with a toxic-metabolic encephalopathy, but he had no epileptic discharges. A polymerase chain reaction of the CSF showed a positive result for VZV and negative for other common aetiologies of bacterial or viral encephalitis. Due to lack of access to his prior urgent care pharmacy records, the physician of the emergency department prescribed IV aciclovir 5 mg/kg for VZV infection. At the emergency department, the physician ruled out differential diagnosis including VZV encephalitis and uremic encephalopathy. Upon re-review of his outpatient medicinal records, it was revealed that he had been prescribed oral aciclovir 800mg five times daily, instead of the recommended aciclovir dose for a patient undergoing haemodialysis (i.e. 200mg twice daily). Thus, the aciclovir dosing was determined to be inappropriate considering his ESRD (dose prescribing error, that caused aciclovir overdose). The aciclovir trough level was therefore done, which showed that the aciclovir drug level was 3.7 µg/mL, which was more than three times than the upper limit of normal trough value (aciclovir toxicity). Based on the clinical presentation and results of the above stated investigations, aciclovir-induced neurotoxicity in the form of acute encephalopathy secondary to inappropriate dosing of aciclovir was diagnosed. The man’s therapy with aciclovir was therefore
Data Loading...
