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O M Korzeniowski

Publications and source records attributed to O M Korzeniowski.

7 recordsLinked to original sources

Species-specific resistance to antimocrobial synergism in Streptococcus faecium and Streptococcus faecalis.

Combinations of penicillin with various aminoglycosidic aminocyclitols were tested against a collection of clinical isolates of Streptococcus faecium in vitro and were used to treat endocarditis caused by S. faecium in the rabbit model. S. faecium proved more resistant to penicillin than Streptococcus faecalis. Even more striking, however, was the resistance to in vitro synergism by combinations of penicillin and various aminoglycosides. At clinically achievable concentrations, penicillin-gentamicin was the only combination that was synergistic against all strains that were tested. Combinations of penicillin and streptomycin and penicillin and amikacin were synergistic only against those strains that were not highly resistant to streptomycin and kanamycin, respectively. Combinations of penicillin with kanamycin, tobramycin, sisomicin, or netilmicin failed to produce synergism against any of these strains. The possible clinical significance of these findings was verified by use of the rabbit model of endocarditis. Combinations of penicillin with gentamicin or streptomycin were synergistic in the therapy of endocarditis that was produced by a strain of S. faecium that did not have a high level of resistance to aminoglycosides. However, the combination of penicillin and netilmicin was no more effective than penicillin alone.

Aminoglycosides

Value of examination for fecal leukocytes in the early diagnosis of shigellosis.

Fecal specimens from 101 patients with diarrhea were cultured and also examined with methylene blue for leukocytes. Thirty-six patients had leukocytes in their stools and 29 had culture-proven shigellosis. The sensitivity of fecal leukocytes in shigellosis was 95% (19/20) when cup specimens were obtained, and 44% (4/9) when swab or diaper specimens were examined. Only 45% of the patients with shigellosis who provided cup specimens had grossly bloody dysentery. Twelve other patients had fecal leukocytes but no demonstrable invasive bacterial pathogens. Methylene blue examination was useful in identifying motile trophozoites of Giardia lamblia and eggs or larvae of other heavy intestinal paraistic infections. Among patients with naturally-acquired acute diarrhea, methylene blue examination of stools for leukocytes is much more sensitive than examination for blood in predicting a positive culture for Shigella spp. It is also of value in detecting parasites.

Acute Disease

Penicillin-netilmicin synergism against Streptococcus faecalis.

The combination of penicillin plus netilmicin was synergistic in vitro against 28 strains of Streptococcus faecalis and compared favorably with penicillin in combination with gentamicin. Similarly, penicillin plus netilmicin was as effective as penicillin plus gentamicin in the therapy of 67 rabbits with enterococcal endocarditis produced with a streptomycin-susceptible (S) or a streptomycin-resistant (R) strain of S. faecalis. After 5 days of infection, control rabbits had bacterial titers of 10(10) colony-forming units (CFU)/g of vegetation. Those treated with penicillin plus netilmicin had mean titers of 10(5.2) and 10(5.1) CFU/g for S and R strains, respectively, and those treated with penicillin plus gentamicin had mean valve titers of 10(5.8) CFU/g for both strains. After 10 days of therapy, mean valve titers with penicillin plus netilmicin were 10(3.8) and 10(4.7) CFU/g, and with penicillin plus gentamicin they were 10(4.5) and 10(5.4) CFU/g for S and R strains, respectively. Thus, if netilmicin proves to be less toxic than other aminoglycoside antibiotics, it may have potential usefulness in the therapy of enterococcal endocarditis.

Animals

In vitro antibiotic susceptibility of salmonellae.

In vitro antibiotic susceptibilities were determined for 101 strains of salmonellae. Resistance to chloramphenicol and ampicillin was low. Cefamandole was active against the majority of strains and deserves further evaluation.

Ampicillin

Comparative pharmacology of cefaclor and cephalexin.

Two cephalosporin antibiotics, cefaclor and cephalexin, were administered orally to healthy, adult male volunteers for comparison of their pharmacological properties. In doses of 250 mg orally, cefaclor produced a peak serum concentration of 6.01 +/- 0.55 (standard deviation [SD]) mug/ml compared with 9.43 +/- 2.36 mug/ml for cephalexin (P < 0.01). The half-lives were 0.58 +/- 0.07 (SD) h and 0.80 +/- 0.12 (SD) h, and elimination constants were 1.22 +/- 0.15 and 0.88 +/- 0.13 h(-1) for cefaclor and cephalexin, respectively (P < 0.001). Neither drug showed accumulation over the dosing period, and both were well tolerated.

Adult

In vitro susceptibility studies with cefaclor and cephalexin.

The in vitro activity of cefaclor and cephalexin against clinical isolates of four bacterial genera was compared. Both agents had a similar range of activity, but cefaclor was significantly more active by weight than cephalexin for most isolates tested.

Bacteria