Treat plays trick on a 3-year-old boy

THE CASE

A 3-year-old boy presents to the emergency department (ED) with a 1-day history of irritability and listlessness. According to his parents, he was well until the night before when he began to behave abnormally, becoming excessively tired approximately 2 hours after eating dinner. During the night, the boy slept poorly, sporadically awakening with crying followed by brief periods of calmness. The morning of presentation, he was difficult to arouse with intermittent fussiness and reluctance to ambulate. 

The patient’s medical and developmental history are unremarkable. A review of systems is negative for headaches, seizures, rash, nausea, vomiting, and abnormal bowel movements. He did not have any new or unusual foods for dinner aside from individually wrapped Halloween candy he had collected while trick-or-treating a week earlier. There are no other unusual ingestions reported, and his parents deny access to any chemicals or medications in the home.

On physical exam, the patient is a well-developed, well-nourished but listless boy with intermittent irritability that is consolable by his mother. The patient appears to be agitated by loud noises, lights, and touch. His temperature is 98.0ºF; heart rate is 130 beats per minute; blood pressure is 106/70 mm Hg; and respiratory rate is 30 breaths per minute. Pupil diameter is 3 mm, equal and reactive to light. Head is normocephalic and atraumatic, and his neck is supple without lymphadenopathy. Cardiac and pulmonary auscultation is unremarkable.

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Abdominal exam reveals normoactive bowel sounds and a soft, nondistended abdomen with diffuse tenderness and voluntary guarding but no rebound tenderness. Neurological exam is limited by participation, but there are no obvious focal neurological deficits and the patient is able to track across midline without nystagmus. Fundoscopic exam is normal with clearly defined optic discs without papilledema. He has normal muscle bulk, tone, and strength throughout but is unwilling to stand or walk without support. Sensation is intact. The patient is unwilling to cooperate with performing a cerebellar examination.

Complete blood count (CBC), basic metabolic panel, urinalysis, hepatic function panel, and serum acetaminophen and salicylate levels are all normal. A chest x-ray and kidneys/ureters/bladder x-ray series are also normal.

NEXT: Differential diagnosis

Differential diagnosis

Altered mental status (AMS) in children is characterized by the inability to respond to stimulation at a level appropriate to the child’s developmental stage.¹ Children who present with AMS should be assessed for impairment of airway, breathing, and circulation, and stabilized before etiology is formally evaluated. Given the extremely broad differential diagnosis, the workup of acute-onset AMS in children is particularly challenging and the vast array of etiologies can be remembered utilizing the Table.²

Detailed and thorough history taking can significantly narrow the differential diagnosis and should encompass medical history; developmental history; medications for the child or others in the home; family history of similar events; recent trauma or illnesses; and prodromal events prior to change in mental status. Review of systems should be expansive and include screening for headaches, seizures, fatigue, rash, nausea, vomiting, abdominal pain, and abnormal bowel movements. A thorough physical exam will help focus the diagnostic evaluation. Vital signs can suggest underlying pathologies such as infection, toxic ingestion, or increased intracranial pressure. A detailed neurological exam is essential.

Focusing on broad categories such as infection, further diagnostic evaluation should include a CBC with differential. Altered mental status with fever suggests central nervous system (CNS) infection such as meningitis or encephalitis, or systemic infection such as sepsis caused by bacteremia or toxin production. Blood and urine cultures should be collected, and lumbar puncture should be performed, particularly in patients demonstrating meningismus or toxicity. The absence of fever and normal CBC in our patient makes an infectious etiology less likely.

Altered mental status caused by intoxication can be accompanied by toxidromes such as bradycardia/bradypnea (eg, from opioids) or tachycardia/tachypnea (eg, from sympathomimetics), and physical exam findings such as abnormal pupil size, nystagmus, and skin changes (flushed, pale, cyanotic). If toxic ingestion is suspected, one should obtain urine toxicology screenings and serum levels of suspected intoxicants.

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It is important to evaluate for painful etiologies that can cause abnormal behavior, particularly in young children who do not localize their pain well. This is particularly true for intussusception. Intussusception is characterized by episodic, colicky abdominal pain with associated irritability that can often cycle through periods of calm reflecting the reduction of the intussusception. This can progress to lethargy and bloody stools when it is no longer irreducible. If clinical suspicion is high for intussusception, consider targeted imaging and surgical consultation.

Metabolic abnormalities such as electrolyte abnormalities or hepatic and renal disorders should also be considered in the evaluation of AMS. A rapid glucose should be performed on any child with AMS. Hypoglycemia can present with palpitations, diaphoresis, irritability, confusion, seizures, or coma.¹ Large abnormalities in serum sodium may present with headache, weakness, irritability, disorientation, and seizures. Obtain serum electrolyte levels and renal and hepatic function tests to evaluate for signs of renal or hepatic failure, and serum ammonia if metabolic disorder is suspected.

Other etiologies to consider include nonaccidental trauma, brain tumor, cerebrovascular disorders, and generalized seizures that can cause prolonged AMS or unresponsiveness in children. Trauma may lead to insufficient cerebral perfusion, diffuse cerebral swelling, increased intracranial pressure, or direct compression of the reticular activating system causing AMS, for which a head computed tomography (CT) scan is warranted. Evaluate for signs of abuse on history and physical exam. Cerebrovascular abnormalities causing AMS are uncommon in otherwise healthy young children, but should be considered in patients with underlying comorbidities such as sickle cell anemia or prothrombotic disorders.¹

Diagnosis

The patient is evaluated for intussusception given his episodic irritability and listlessness and tenderness on abdominal exam. An abdominal ultrasound is ordered, which shows no evidence suggesting intussusception. A head CT scan also is ordered to evaluate for intracranial pathology.

On further questioning of unusual ingestions, the parents reveal that after their son ate the Halloween candy he had collected from trick-or-treating, his eyes “flickered left and right.” When directed to retrieve the candy, the patient’s uncle later arrives to the ED with the candy wrapper, revealing a chocolate bar that contains 90 mg THC (delta-9-tetrahydrocannabinol)-the active ingredient of marijuana (cannabis). A urine toxicology screen is performed and the diagnosis of cannabis intoxication is confirmed. Evaluation for intussusception is subsequently aborted, and the head CT scan is cancelled.

NEXT: Cannibis ingestion

Cannabis ingestion

A study by Wang et al (2013) found that unintentional cannabis exposure in young children is increasing in the United States and that most pediatric cannabis exposures are from ingestion of medical marijuana in food products.³ This may be because of the increased presence of cannabis in the household as well as improved palatability of THC-containing foods, including edible candy and baked goods that are appealing to young children. Unintentional poisonings are common in young children, therefore education of caregivers on primary prevention of potential toxic exposures in the household and reference to poison control centers locally or nationally (800-222-1222) are important.

Many patients who ingest cannabis may experience CNS alterations such as irritability, depressed mental status, or ataxia.^4,5 Other symptoms include jerking, conjunctival hyperemia, emesis, tachycardia, and tremor.⁶ If severe, respiratory insufficiency and coma may result.⁷ Although most cases of cannabis ingestion do not have serious sequelae, young patients may be exposed to a myriad of unnecessary tests, procedures, and imaging during evaluation if the diagnosis is unclear or exposure to cannabis is not known.⁸ Knowing about cannabis exposure up front is associated with fewer ancillary tests; however, even when cannabis exposure is accidental, families may be reluctant to report it to healthcare facilities because they fear legal ramifications.⁹

Treatment of cannabis intoxication is primarily supportive, including monitoring and managing respiratory and hydration status until recovery. There is no specific antidote for cannabis intoxication currently available. Unnecessary stimulation of an affected patient should be avoided. In some cases, benzodiazepines may be given as an anxiolytic.

Patient outcome

The patient is further observed in the ED after the diagnosis of cannabis intoxication. Given the potential for child neglect, child protective services is consulted. The patient is admitted overnight for monitoring on intravenous fluids and recovers completely by the next morning, demonstrating adequate oral intake. Child protective services files a report and the child is sent home under the care of his parents.

Conclusion

The differential diagnosis of AMS in children is extremely broad and should be approached with a detailed and comprehensive history and physical exam once the patient is stabilized. Narrowing the differential diagnosis with a thorough history and physical exam will allow the avoidance of unnecessary and possibly invasive tests and help guide diagnostic evaluation. Healthcare providers should specifically inquire about potential toxic exposures and ingestions, and should be aware of the presenting symptoms.

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Given increased pediatric exposure to cannabis in US households, providers should consider cannabis intoxication in a child with AMS and become familiar with its presentation and management, which is primarily supportive. A diagnosis of cannabis ingestion, even if unintentional, should be reported to child protective services. Prevention should focus on education of caregivers through primary prevention and poison control centers for reference.

REFERENCES

1. Singer JI. Altered mental status in children. In: Tintinalli JE, Stapczynski JS, Cline DM, Ma OJ, Cydulka RK, Meckler GD, eds. Tintinalli's Emergency Medicine A Comprehensive Study Guide. 7th ed. New York: McGraw-Hill; 2011:chap 131. Available at: http://accessmedicine.mhmedical.com/content.aspx?bookid=348&Sectionid=40381604. Accessed September 9, 2016.

2. Baren JM, Rothrock SG, Brennan J, Brown L. Chapter 11: Altered mental status/coma. In: Pediatric Emergency Medicine. Philadelphia, PA: Elsevier Health Sciences; 2008:115-122.

3. Wang GS, Roosevelt G, Heard K. Pediatric marijuana exposures in a medical marijuana state. JAMA Pediatr. 2013;167(7):630-633.

4. Geller T, Loftis L, Brink DS. Cerebellar infarction in adolescent males associated with acute marijuana use. Pediatrics. 2004;113(4):e365e370.

5. Bonkowsky JL, Sarco D, Pomeroy SL. Ataxia and shaking in a 2-year-old girl: acute marijuana intoxication presenting as seizure. Pediatr Emerg Care. 2005;21(8):527-528.

6. Borgelt LM, Franson KL, Nussbaum AM, Wang GS. The pharmacologic and clinical effects of medical cannabis. Pharmacotherapy. 2013;33(2):195-209.

7. Macnab A, Anderson E, Susak L. Ingestion of cannabis: a cause of coma in children. Pediatr Emerg Care. 1989;5(4):238-239.

8. Wang GS, Roosevelt G, Le Lait MC, et al. Association of unintentional pediatric exposures with decriminalization of marijuana in the United States. Ann Emerg Med. 2014;63(6):684-689.

9. Wang GS, Narang SK, Wells K, Chuang R. A case series of marijuana exposures in pediatric patients less than 5 years of age. Child Abuse Negl. 2011;35(7):563-565.

Ms Nguyen is a fourth-year medical student, David Geffen School of Medicine at the University of California, Los Angeles. Dr Cho is associate professor of pediatrics, Division of Academic General Pediatrics, Cedars-Sinai Medical Center, Los Angeles, California. The authors have nothing to disclose in regard to affiliations with or financial interests in any organizations that may have interest in any part of this article.