What is the cause of seizure-like movement in an 88-year-old patient recovering from agranulocytosis and retropharyngeal abscess, while being treated with Daptomycin (daptomycin), Piperacillin/Tazobactam (piperacillin/tazobactam), with a negative head CT scan?

From the Guidelines

The seizure-like movements in this 88-year-old patient recovering from agranulocytosis and retropharyngeal abscess, despite a negative CT head, are concerning and require prompt evaluation for potential neurotoxicity from daptomycin or piperacillin-tazobactam. These movements may represent neurotoxicity from daptomycin, which can cause myoclonus, tremors, and seizure-like activity, particularly in elderly patients with renal impairment 1. I recommend immediately checking daptomycin levels and renal function, and considering switching to an alternative antibiotic such as linezolid or vancomycin if daptomycin toxicity is suspected. Piperacillin-tazobactam can also rarely cause neurotoxicity, especially in elderly patients with renal dysfunction. An urgent neurology consultation, EEG to evaluate for seizure activity, and comprehensive metabolic panel to check for electrolyte abnormalities (particularly sodium, calcium, and magnesium) are essential. While continuing infection treatment, ensure adequate hydration, correct any electrolyte imbalances, and consider a short course of benzodiazepines if movements are severe. Close monitoring is crucial as these movements could represent either medication side effects or neurological complications of the infection despite the negative CT scan. The choice of antibiotic should be guided by the principles outlined in the clinical practice guideline for the use of antimicrobial agents in neutropenic patients with cancer, which recommends monotherapy with an anti-pseudomonal b-lactam agent, such as cefepime, a carbapenem, or piperacillin-tazobactam, for high-risk patients requiring hospitalization for IV empirical antibiotic therapy 1. However, in this case, the potential for neurotoxicity with daptomycin and piperacillin-tazobactam takes precedence, and alternative antibiotics should be considered to minimize the risk of adverse effects on the patient's quality of life and mortality. Key considerations in managing this patient include:

• Prompt evaluation for potential neurotoxicity from daptomycin or piperacillin-tazobactam
• Checking daptomycin levels and renal function
• Considering alternative antibiotics such as linezolid or vancomycin
• Urgent neurology consultation and EEG to evaluate for seizure activity
• Comprehensive metabolic panel to check for electrolyte abnormalities
• Ensuring adequate hydration and correcting any electrolyte imbalances
• Considering a short course of benzodiazepines if movements are severe.

From the FDA Drug Label

The FDA drug label does not answer the question.

From the Research

Recovery from Agranulocytosis and Retropharyngeal Abscess

• The patient is an 88-year-old individual recovering from agranulocytosis and retropharyngeal abscess, and is being treated with daptomycin, piperacillin, and tazobactam 2, 3.
• Agranulocytosis is a rare and potentially life-threatening condition, and the patient's age and medical history may increase the risk of complications 3, 4.
• Retropharyngeal abscess is a serious condition that requires prompt diagnosis and treatment, and the patient's treatment plan includes surgical drainage and intravenous antibiotics 2, 5.

Treatment and Management

• The patient is being treated with broad-spectrum antibiotics, including daptomycin, piperacillin, and tazobactam, which is a common approach for treating retropharyngeal abscess and agranulocytosis 2, 3.
• The use of hematopoietic growth factors, such as granulocyte colony-stimulating factor, may also be considered to help manage the patient's agranulocytosis 3.
• Weekly monitoring of the patient's absolute neutrophil count (ANC) may be necessary to detect any potential complications or adverse reactions to treatment 6.

Prognosis and Outcome

• The patient's prognosis and outcome will depend on various factors, including the severity of the retropharyngeal abscess and agranulocytosis, the effectiveness of treatment, and the patient's overall health and medical history 2, 3.
• With prompt and appropriate treatment, the patient's outcome is likely to be good, but close monitoring and follow-up care will be necessary to prevent any potential complications or relapses 2, 5.