Snapshot A 56-year-old man presents to the emergency department for a severe headache, generalized malaise, and fatigue. Her symptoms are associated with neck stiffness and nausea. Physical examination is significant for nuchal rigidity and an inability to extend at the knee while the hips are flexed at 90°. A lumbar puncture is performed and cerebral spinal fluid studies demonstrate an elevated opening pressure, elevated protein, decreased glucose, and a leukocytosis. Gram stain of the cerebral spinal fluid demonstrates lancet-shaped, gram-positive cocci. Introduction Classification lancet-shaped, gram-positive cocci that are α-hemolytic encapsulated optochin sensitive quellung reaction positive contain IgA protease Epidemiology incidence adults the most common cause of pneumonia and meningitis children the most common cause of otitis media Pathogenesis contains a polysaccharide capsule that protects it from phagocytosis contains the ability to adhere and form a robust biofilm in the nasopharynx, sinuses, and inner ear after epithelial invasion, an inflammatory host immune response ensues Associated conditions meningitis otitis media pneumonia sepsis Presentation Symptoms meningitis headache neck stiffness otitis media inner ear pain pneumonia shortness of breath productive cough pleuritic chest pain Physical exam meningitis nuchal rigidity Bruzinski sign neck flexion leads to flexing of the knees while the patient is supine Kernig sign extension of the knee while the hips are flexed at 90° causes pain/discomfort otitis media fever irritability ear-tugging/rubbing pneumonia decreased breath sounds increased fremitus dullness to percussion rales Studies Gram stain and culture sputum cerebral spinal fluid blood Differential Other causes of meningitis N. meningitidis gram-negative diplococci L. monocytogenes gram-positive rods Other causes of otitis media M. catarrhalis gram-negative diplococci Other causes of pneumonia respiratory viruses Treatment Preventative pneumococcal vaccine indication pneumococcal polysaccharide vaccine (PPV) pneumococcal capsular vaccine (PCV) Medical penicillin, a penicillin derivative, or a 3rd generation cephalosporin indication in penicillin-susceptible pneumococci causing pneumonia comments penicillin-resistant strains are treated with vancomycin amoxicillin or amoxicillin-clavulanate indication in acute otitis media ceftriaxone and vancomycin indication to cover S. pneumonia, N. meningitidis, and H. influenzae as a cause of meningitis Complications Septic shock