A 12-years-old child presented to the emergency department with a 4-day history of vomiting. Case History Examined by primary care provider (twice) A laboratory workup: WBC count: 20,500 Urine analysis: specific gravity of 1.019, large blood, 4+ protein, and trace ketones. The child was given ceftriaxone 450 mg intramuscularly for a presumptive urinary tract infection (UTI). The child returned to the office 2 days later with persistent vomiting, was dehydrated, and was referred to the emergency department.

Reported 4 to 6 episodes of non-bloody, nonbilious emesis, which seemed to be clustered in the morning and at bedtime. Decreased oral intake and activity. Physical Examination The child was pale in appearance and fussy yet consolable by his mother. Vital signs were: Temperature: 98.7° F Pulse: 144 beats/minute Respiratory rate: 32 breaths/minute Blood pressure (BP): 145/88 mm Hg Pulse…