Cephazolin treatment of pneumococcal pneumonia and urinary tract infections

Ten cases of pneumococcal pneumonia were treated with cephazolin 500 mg. q8h for at least 5 days. In every case therapy was accompanied by clinical improvement and eradication of the organism. Ten patients with E. coli bacteriuria (5 symptomatic) were treated with cephazolin 500 mg. q12h for 7 to 10 days. In every case the pathogen was eliminated during therapy but in one case bacteriologic relapse occurred following cessation of therapy. In 10 cases of bacteriuria caused by P. mirabilis, Klebsiella sp, Enterobacter, and Enterococcus, the urine became sterile during treatment, but relapse was common. Initial and final creatinine clearances obtained in 29 patients who received an average of 12.9 g. of cephazolin showed no tendency toward loss of renal function. Serial serum levels of cephazolin were determined following the first 500 mg. dose in 18 patients. The peak serum level occurred at one hour with a serum half life of approximately 2.2 hours. For 13 of these 18 patients serial serum levels were also obtained following the last dose of cephazolin. At this time the mean peak level occurred at 2 hours but again the serum half life was approximately 1.9 hours.