A 25-year-old male presents with severe, sudden-onset headache and neck stiffness. He has a history of recurrent sinusitis and had been self-treating with antibiotics obtained online. What might be the diagnosis?
The patient's symptoms suggest meningitis, a serious infection of the membranes surrounding the brain and spinal cord. His history of self-treatment for sinusitis with antibiotics obtained online could have led to inappropriate antibiotic use, potentially allowing a resistant organism to proliferate and spread to the meninges. This is a medical emergency and requires immediate administration of broad-spectrum antibiotics and likely a lumbar puncture to identify the causative organism.