The observations of Rogers are interesting. Although I do not know of specific investigations that relate the outcome of meningitis to smiling, I agree that the ability of the child with meningitis to respond to social overtures with this type of behavior indicates a level of intact central nervous system functioning that gives the physician some cause for optimism.
In the clinical situation in which the diagnostic possibility of meningitis is being considered, smiling is one of several important behaviors, the presence of which helps to rule out this diagnosis. Not uncommonly, repeated observations of a febrile child or attempts to make the child more comfortable (by placing the child in the parent's arms or by antipyresis) will allow the pediatrician to elicit smiling behavior. In one study,1 the negative predictive value of a normal response to social overtures (smiling or, in the infant less than 2
McCarthy PL. What's a Smile Worth?-Reply. Arch Pediatr Adolesc Med. 1994;148(12):1356. doi:10.1001/archpedi.1994.02170120118031