A 13-year-old male arrived to the emergency department (ED) via ambulance for an acute allergic reaction. The child had been in his usual state of health until five days prior to the date of admission, when he began vomiting. He was seen two days prior to admission at an outlying clinic, which diagnosed him as having sinusitis and a urinary tract infection. He was initially prescribed amoxicillin with clavulanate. His antibiotic was changed to amoxicillin on the day of admission, because it was thought that his vomiting was from the clavulanate component. Upon receiving the first dose of amoxicillin, he vomited coffee-ground-colored material, and he was noted to have edema of the face. Emergency medical services were called, the patient was treated in the field with diphenhydramine intramuscularly, and he was transported to the ED.The patient's medical history was significant for autism with self-mutilating behavior and mental retardation. No surgical or allergic history was reported. On physical examination the heart rate was 100 beats/min, the respiratory rate was 12 breaths/min, the blood pressure was 88/52 mm Hg, the temperature was 99.8ЊF, and pulse oximetry was 99% on room air. The patient's general appearance was that of an uncomfortable, weak-looking male, with extensive edema of the face. The head, ears, nose, and throat examination was significant for the massive edema and erythema with the eyes closed secondary to the edema; the nasal mucosa was edematous; the oral mucosa was dry and the pharynx was not well visualized. The ear canals were obstructed by wax. The neck was supple. The cardiovascular examination was normal except for the tachycardia. The lungs were clear bilaterally with equal breath sounds. The abdominal examination was normal. The extremities had no cyanosis or edema; there was some evidence of old trauma. The capillary refill was 2 seconds. Though the patient was uncooperative, there was no focality identified on the neurologic exam. Laboratory testing revealed the following: white blood cell count of 29,000/mm 3 with a differential of 88% neutrophils, 4% lymphocytes, and 7% monocytes; a sodium of 148 mmol/L, a potassium of 4.0 mmol/L, a chloride of 94 mmol/L, a bicarbonate of 25 mmol/L, a glucose of 237 mg/dL, a BUN of 70 mg/dL, and a creatinine of 2.8 mg/dL.The patient was taken to the resuscitation area of the ED and placed on a cardiac monitor with pulse oximetry. Three doses of epinephrine, 0.3 mL (1:1,000), were administered subcutaneously and two boluses of 20 mL /kg of normal saline were given intravenously. The patient was initially diagnosed as having an anaphylactoid reaction, dehydration with renal failure, and gastritis. His vital signs stabilized after initial resuscitation and he was started on maintenance fluids. He was admitted to the pediatric intensive care unit (PICU), where he received maintenance intravenous hydration with D 5 1/3NS, diphenhydramine, and methylprednisolone intravenously every six hours, and ranitidine intravenously every eight hours. An immunolog...
