What is the next step in managing a 19-year-old patient with numbness in fingers and bilateral legs that started after a streptococcal (strep) infection, who is currently on antibiotics such as penicillin or amoxicillin?

Immediate Neurological Evaluation Required for Possible Guillain-Barré Syndrome

This patient requires urgent neurological consultation and hospitalization for suspected Guillain-Barré syndrome (GBS), as the acute onset of bilateral peripheral numbness following a streptococcal infection is a classic presentation of post-infectious autoimmune neuropathy.

Critical Next Steps

Immediate Actions

• Stop routine strep throat management and shift focus to neurological emergency evaluation - the bilateral ascending numbness pattern starting in fingers and legs within 2 days of strep infection is highly concerning for GBS, which can progress rapidly to respiratory failure
• Obtain urgent neurology consultation - GBS requires specialized assessment including detailed neurological examination for motor weakness, areflexia, and sensory deficits
• Hospitalize for monitoring - respiratory function can deteriorate rapidly in GBS, requiring ICU-level observation with serial vital capacity measurements and negative inspiratory force testing

Diagnostic Workup

• Lumbar puncture - looking for albuminocytologic dissociation (elevated CSF protein with normal cell count), the hallmark finding in GBS that typically appears 1-2 weeks after symptom onset
• Nerve conduction studies and EMG - to confirm demyelinating or axonal neuropathy pattern, though these may be normal in the first week
• Baseline pulmonary function tests - forced vital capacity (FVC) and negative inspiratory force (NIF) to establish respiratory baseline before potential decline

Clinical Reasoning

Why This Is Not Simple Strep Pharyngitis

While the patient is appropriately on antibiotics for strep throat 1, 2, the neurological symptoms represent a separate and more urgent problem. The timing (2 days post-infection) and distribution (bilateral peripheral) of numbness are inconsistent with direct streptococcal complications and instead suggest post-infectious autoimmune pathology.

Post-Streptococcal Complications Context

The guidelines focus on preventing rheumatic fever and post-streptococcal glomerulonephritis as the main non-suppurative complications of GAS infection 1. However, GBS, while not mentioned in strep pharyngitis guidelines 1, is a well-recognized post-infectious neuropathy that can follow various infections including streptococcal infections. The acute bilateral peripheral neuropathy presentation in a young patient 2 days after confirmed strep infection fits the classic GBS temporal pattern.

Common Pitfalls to Avoid

• Do not dismiss neurological symptoms as anxiety or viral illness - bilateral peripheral numbness is never a normal finding and requires investigation
• Do not delay evaluation waiting for motor weakness - sensory symptoms can precede motor involvement in GBS, and early recognition improves outcomes
• Do not assume the antibiotics will resolve the neurological symptoms - while continuing antibiotics for the strep infection is appropriate 2, GBS is an autoimmune process that requires different treatment (IVIG or plasmapheresis)
• Do not manage outpatient - GBS can progress to respiratory failure within hours to days, requiring continuous monitoring

Regarding the Streptococcal Infection

Continue the current antibiotic regimen (penicillin or amoxicillin) for the full 10-day course to eradicate the streptococcal infection and prevent rheumatic fever 1, 2. However, this is now a secondary concern compared to the acute neurological emergency.