A 17-year-old girl is admitted to the hospital due to lower extremity weakness. Onset of tingling in the patient's feet began 5 days ago; she then developed weakness 3 days ago, which has been worsening, and now she cannot stand or walk. She had an upper respiratory infection 2 weeks ago; otherwise, medical history is unremarkable. Temperature is 36.7 C (98 F), blood pressure is 110/70 mm Hg, pulse is 85/min, and respirations are 18/min. Pulse oximetry is 99% on room air. Physical examination shows an adolescent girl in no acute distress and clear lungs on auscultation. Bilateral ankle and knee flexion/extension strength is 1/5, and hip flexors are 2/5. Reflexes are absent in the lower extremities. The upper extremities have 3/5 strength and 1+ reflexes. The patient can keep her head erect and swallow saliva. Gag reflex is intact. Cerebrospinal fluid results are as follows: Which of the following is the most appropriate next step in management of this patient?

Question

A 17-year-old girl is admitted to the hospital due to lower extremity weakness.  Onset of tingling in the patient's feet began 5 days ago; she then developed weakness 3 days ago, which has been worsening, and now she cannot stand or walk.  She had an upper respiratory infection 2 weeks ago; otherwise, medical history is unremarkable.  Temperature is 36.7 C (98 F), blood pressure is 110/70 mm Hg, pulse is 85/min, and respirations are 18/min.  Pulse oximetry is 99% on room air.  Physical examination shows an adolescent girl in no acute distress and clear lungs on auscultation.  Bilateral ankle and knee flexion/extension strength is 1/5, and hip flexors are 2/5.  Reflexes are absent in the lower extremities.  The upper extremities have 3/5 strength and 1+ reflexes.  The patient can keep her head erect and swallow saliva.  Gag reflex is intact.  Cerebrospinal fluid results are as follows:  Which of the following is the most appropriate next step in management of this patient?

Quizplus · Accepted Answer

11ec25c8_d6ed_8551_bc81_834911665b32_MD0003_00 This patient has ascending weakness and areflexia consistent with Guillain-Barré syndrome (GBS), a polyneuropathy caused by immune-mediated demyelination of peripheral nerve fibers. Most patients have a preceding respiratory or gastrointestinal (Campylobacter) infection that triggers an initial antibody response, which then acts on similar antigens on myelin and axons. Paresthesia often accompanies the weakness, which can spread from the lower extremities to involve the thorax, upper extremities, and cranial nerves (ie, bulbar palsy). Diagnosis is primarily clinical and supported by cerebrospinal fluid findings of elevated protein and normal leukocytes (ie, albuminocytologic dissociation), as seen in this patient. Neuromuscular respiratory failure is a life-threatening complication found in up to 30% of patients. Once GBS is suspected in a hemodynamically stable patient, the next step in management is to assess pulmonary function with spirometry. Forced vital capacity (FVC) and negative inspiratory force monitor respiratory muscle strength, and serial pulmonary function testing should be performed given the potential for rapid progression of disease. A decline in FVC (≤20 mL/kg) indicates impending respiratory failure warranting endotracheal intubation. Additional indications for elective or emergency intubation include respiratory distress (eg, tachypnea, accessory muscle use), severe dysautonomia (eg, heart rate and blood pressure instability), or widened pulse pressure (Choice B). With early diagnosis and cardiopulmonary monitoring and support, most young patients experience spontaneous recovery. spirometry (Choice A) GBS can lead to aspiration pneumonia in the setting of bulbar muscle weakness, which is not seen in this patient. In addition, this patient has no other findings suggestive of pneumonia such as fever, cough, or crackles on auscultation. (Choice C) Muscle biopsy can be considered in the evaluation of muscle weakness and myalgia. This patient's paresthesia and areflexia are more indicative of a primary neuropathy, making muscle biopsy unnecessary. (Choice D) Spinal MRI may reveal enhancement of nerve roots and cauda equina in GBS. However, MRI findings do not confirm the diagnosis or affect management; pulmonary function testing is more urgently indicated to assess respiratory muscle strength. (Choice F) Testing for botulism is performed when a patient has descending progression of weakness. This patient's symptoms are ascending, making botulism unlikely. Educational objective: Guillain-Barré syndrome most commonly presents with ascending weakness and areflexia, and can progress to involve respiratory and bulbar muscles. Serial pulmonary function testing (eg, spirometry) of forced vital capacity and negative inspiratory force is indicated to monitor for impending respiratory failure. References: Guillain-Barré syndrome. (http://www.ncbi.nlm.nih.gov/pubmed/23418763) Simple bedside predictors of mechanical ventilation in patients with Guillain-Barre syndrome. (http://www.ncbi.nlm.nih.gov/pubmed/24378177) Vital capacity versus maximal inspiratory pressure in patients with Guillain-Barré syndrome and myasthenia gravis. (http://www.ncbi.nlm.nih.gov/pubmed/21748507)

A 17-Year-Old Girl Is Admitted to the Hospital Due to Lower