Case 3: Pain and Weakness in a 12-year-old Boy

Presentation

A 12-year-old previously healthy boy presents to his pediatrician with right-sided posterior rib pain in the context of a recent respiratory infection without associated fever. Over the next 10 days he presents another 3 times with vague symptoms of left posterior neck pain, diffuse abdominal pain, nausea, and decreased oral intake. Results of abdominal imaging, a complete blood cell count, and a comprehensive metabolic panel are normal except for increased stool burden on radiography.

The following day he presents to the emergency department, where he complains of continued abdominal pain, decreased appetite, and no urine output for 24 hours. He receives intravenous fluids and analgesics, after which his urine output, energy, and general appearance improve, and he is deemed stable for discharge. As he is leaving the emergency department, he states that he is unable to walk and is having left arm weakness and multiple episodes of urinary incontinence. Physical examination is repeated, with vital signs significant for tachycardia (heart rate of 146 beats/min) and hypertension (blood pressure of 151/83 mm Hg). He has paralysis and hypertonia of his left upper and bilateral lower extremities, decreased deep tendon reflexes throughout all extremities, pain with movement of the body, palpable stool burden, and suprapubic fullness. His sensory examination findings are normal, with no specific sensory level.

He is admitted to the hospital for further evaluation. Results of serum studies are normal. Cerebrospinal fluid (CSF) studies show an elevated white blood cell count (112/μL [0.1 × 10⁹/L]) but otherwise normal findings, including levels of protein (45 mg/dL [0.45 g/L]), glucose (58 mg/dL [3.2 mmol/L]), and red blood cells (2/μL [0.000002 …