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Unintentional Marijuana Exposure Presenting as Altered Mental Status in the Pediatric Emergency Department: A Case
1Seattle Children's Hospital, Department of Pediatrics, Division of Emergency Medicine University of Washington School of Medicine, Seattle, Washington.
Insights
Unintentional tetrahydrocannabinol (THC) exposure in children can cause altered mental status, leading to extensive testing. Awareness of THC exposure symptoms can help emergency physicians avoid unnecessary invasive procedures in pediatric patients.
Area of Science:
- Pediatric Emergency Medicine
- Toxicology
Background:
- Unintentional tetrahydrocannabinol (THC) exposure in children can manifest as altered mental status.
- Altered mental status in pediatric patients frequently prompts invasive diagnostic evaluations.
Observation:
- Three pediatric cases in Washington state presented to a tertiary care emergency department with altered mental status.
- Urine toxicology screens were positive for inactive THC metabolites in all three pediatric patients.
- Symptoms included vomiting, lethargy, hallucinations, nausea, slurred speech, and ataxia.
Findings:
- Extensive work-ups were performed before diagnosing THC exposure in all cases.
- Two children were discharged home, while one required pediatric intensive care unit admission.
- Delayed diagnosis of THC exposure occurred despite presenting symptoms.
Implications:
- Increased marijuana legalization necessitates emergency physician awareness of THC exposure in pediatric altered mental status cases.
- Physicians should inquire about potential exposure to marijuana products and acknowledge potential caretaker reluctance in disclosure.
- Recognizing clinical effects of THC exposure can reduce unnecessary invasive testing in stable pediatric patients.
Background:
Unintentional tetrahydrocannabinol (THC) exposure in pediatric patients can present as altered mental status. Altered mental status in a pediatric patient often leads to invasive diagnostic testing.
Case Report:
The following cases describe 3 pediatric patients in Washington state who presented to a tertiary care children's hospital emergency department (ED) with altered mental status, later found to have urine toxicology screening positive for inactive THC metabolite (positive THC toxicology screen). Case 1 is a 6-year-old boy who presented with vomiting, lethargy, and hallucinations. Case 2 is a 5-year-old girl who presented with nausea, slurred speech, ataxia, and lethargy in the setting of a minor head injury. Case 3 is a 7-month-old boy who presented with vomiting and lethargy in the setting of a minor fall the day prior to ED evaluation. All children had extensive work-ups before the diagnosis was made; 2 were discharged home and 1 was admitted to the pediatric intensive care unit. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: As access to marijuana increases with growing legalization, it is important to be familiar with state marijuana legislation, to consider and ask families about access to marijuana products as a potential contributor to altered mental status, and to be aware of potential caretaker reluctance regarding disclosure of marijuana use secondary to perceived stigma. Maintaining awareness of the clinical effects of THC exposure in children may limit invasive testing in a hemodynamically stable child with altered mental status.
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