The effects of pre-admission antibiotics on the bacteriological diagnosis of pyogenic meningitis.

To assess the effects of pre-admission antibiotics on the accuracy of bacterial diagnosis in pyogenic meningitis, the case records of 154 patients admitted to an infectious diseases unit during a 10-year period (1966-1975) were reviewed. The causative organism was identified in 140 patients (91%). Although 63 patients had received antibiotics before admission, a bacteriological diagnosis was still possible in 57 of these (90%).