A 2-year-old boy is brought to the office by his parents for evaluation after he lost consciousness earlier today. The patient was running around at a playground when he tripped and fell, landing on his outstretched hands. He did not hit his head on the ground. The patient gasped and, instead of crying, suddenly became pale, limp, and diaphoretic and then lost consciousness. There were no clonic movements. He regained consciousness after several seconds and returned to normal activity within 2-3 minutes. The patient has otherwise been healthy, but his mother says that he had a similar episode a month ago. Temperature is 36.7 C (98.1 F), blood pressure is 90/50 mm Hg, pulse is 100/min, and respirations are 20/min. Pulse oximetry is 100% on room air. On examination, the patient is alert and playful. Heart sounds are normal with no murmurs. Neurologic examination shows no focal deficits. The skin has a normal color. The patient has 2+ peripheral pulses. Which of the following testing is required to establish this patient's most likely diagnosis?

Question

A 2-year-old boy is brought to the office by his parents for evaluation after he lost consciousness earlier today.  The patient was running around at a playground when he tripped and fell, landing on his outstretched hands.  He did not hit his head on the ground.  The patient gasped and, instead of crying, suddenly became pale, limp, and diaphoretic and then lost consciousness.  There were no clonic movements.  He regained consciousness after several seconds and returned to normal activity within 2-3 minutes.  The patient has otherwise been healthy, but his mother says that he had a similar episode a month ago.  Temperature is 36.7 C (98.1 F), blood pressure is 90/50 mm Hg, pulse is 100/min, and respirations are 20/min.  Pulse oximetry is 100% on room air.  On examination, the patient is alert and playful.  Heart sounds are normal with no murmurs.  Neurologic examination shows no focal deficits.  The skin has a normal color.  The patient has 2+ peripheral pulses.  Which of the following testing is required to establish this patient's most likely diagnosis?

Quizplus · Accepted Answer

Explanation: 11ec25c8_d5db_7908_bc81_e1c06689f762_MD0003_00 This child's brief syncope after a minor fall is consistent with a breath-holding spell (BHS), a common and benign childhood condition that is classified as cyanotic or pallid: Cyanotic BHS: Triggered by vigorous crying, leading to breath-holding, cyanosis, and loss of consciousness (LOC) with rapid return to baseline. Pallid BHS (less common): Typically occurs after minor trauma and without crying, as seen in this patient. Pain or fear causes the heart rate to slow and the child to hold the breath and become pale, diaphoretic, and limp. Brief LOC follows, and patients are sometimes sleepy or confused for a short period after. LOC during a BHS is typically <1 minute; diagnosis is clinical and requires no further testing when presentation is classic. However, screening for associated iron deficiency anemia is recommended because iron-deficient patients typically experience improvement in BHS frequency with iron therapy. (Choice A) Patients with atypical BHS (eg, multiple daily episodes, duration >1 min) or a family history of cardiac disease or sudden death should undergo an ECG to evaluate for arrhythmias (eg, prolonged QT syndrome). This patient's classic pallid BHS does not require cardiac evaluation. (Choice B) CT scan of the head is performed for suspected brain injury in patients with altered mental status and LOC after head trauma. This patient did not hit his head, and CT scan is not indicated for BHS. (Choice C) An echocardiogram can assess for tetralogy of Fallot (TOF), which can lead to LOC after crying due to right ventricular outflow tract obstruction. These tet spells are characterized by cyanosis, not pallor, and can be differentiated from cyanotic BHS by rapid and deep breathing, not breath-holding. Moreover, patients with TOF typically have a harsh systolic murmur (ie, pulmonic stenosis), which is not seen in this child. (Choice D) Classic pallid BHS can be differentiated from seizure by a history of provocation (eg, minor fall) and lack of tonic-clonic movements. If a patient is monitored during a spell, the presence of bradycardia prior to LOC also supports a diagnosis of pallid BHS. Notably, atypical BHS with prolonged apnea (>1 min) can rarely cause seizure activity, making clinical diagnosis difficult and warranting electroencephalogram, but this is not the case here. Educational objective: Pallid breath-holding spells are triggered by fear or pain from minor trauma and are characterized by pallor/diaphoresis with brief loss of consciousness that may be followed by sleepiness/confusion. Diagnosis is clinical and requires no testing. References: Breath-holding spells in pediatrics: a narrative review of the current evidence. (http://www.ncbi.nlm.nih.gov/pubmed/30421679)

A 2-Year-Old Boy Is Brought to the Office by His