Key words: Staphylococci, Classification, Antibiotic-susceptibility, Opportunistic infection
Table 1. Species classification of staphylococcal isolates from clinical specimens Figures in parentheses indicate no. of coagulase-negative staphylococci suspected to a causal pathogen Others are isolates from drain tubs, gauzes, saliva, nasal swabs and secretions, and tissue specimens. Table 2. Occurrence of coagulase-negative staphylococci from urinary tract infections Table 3. Novobiocin resistance of coagulasenegative staphylococci * Isolation with>105cfu/ml was suspected of a causal pathogen Resistance:> 1.6 Đg/ml
Table 4. Various antibiotic resistance of major staphylococcal isolates * Resistance: MIC > 25ƒÊg/ml. Table 5. Ocurrence of drug-resistant strains in staphylococcal isolates * Resistance : MIC > 25ƒÊg/ml. pattern of S. aureus Table 6. Major multiple drug-resistance * Others are randam multiple drug -resistance pattern other than the ones indicated above. ** Resistance: MIC > 25 ƒêg/ml.
Table 7. Multiple drug-resistance of coagulasenegative staphylocccci Resistance: MIC > 25 4ƒÊg/ml.
1) Baird-Parker, A. C.: Genus II. Staphylococcus Rosenbach 1884, 18 nom. cons. Opin. 17 Jud. comm. 1958, R.E. Buchanan & N. E. Gibons (ed), Bergey's manual of determinative bacteriology, 8th ed, The Willams & Wilkins Co., Baltimor, p. 483-489, 1974. 2) Brandt, L. & Swahn, B.: Subacute bacterial endocarditis due to coagulase-negative Staphylococcus albus. Acta Med. Scand., 166: 125 132, 1960. 3) Pereira, A.T.: Coagulase-negative strains of staphylococcus possessing antigen 51 as agents of urinary infection. J. Clin. Path., 15: 252 253, 1962. 4) Mabeck, C.E. : Significance of coagulasenegative staphylococcal bacteriuria. Lancet, 2: 1150-1152, 1969. 5) Wallmark, G., Arremark, I. & Telander, B.: Staphylococcusaprophyticus: A frequent cause of acute urinary tract infection among female outpatients. J. Infect. Dis., 138: 791-797, 1978. 6) Quinn, E.L., Cox, F. & Fisher, M.: The problem of associating coagulase-negative staphylococci with disease. Ann. N. Y. Acad. Sci., 128: 428-442, 1967. 7) Verhoef, J., van Boven, C. P. A. & Winkler, K.C.: Characters of phages from coagulasenegative staphylococci. J. Med. Microbiol., 4: 413-424, 1971. 8) Verhoef, J., van Boven, C. P. A. & Winkler, K. C. Phage-typing of coagulase-negative staphylococci. J. Med. Microbiol., 5: 9-19, 1972. 9) Baird-Parker, A.C.: The basis for the present classification of staphylococci and micrococci. Ann. N. Y. Acad. Sci., 236: 7-14, 1974. 10) Kloos, W.E. & Schleifer, K.H.: Simplified scheme for routine identification of human Staphylococcus species. J. Clin. Microbiol., 1: 82-88, 1975. 11) Skerman, V.B.D., Mcgowan, V. & Sneath, P. H. A.: Approved lists of bacterial names. Inter. J. Syst. Bact., 30: 225-420, 1980. 14) Schleifer, K. H. & Kloos, W. E.: Isolation and characterization of staphylococci from human skin. 1. Amended descriptions of Staphylococcus epidermidis and Staphylococcus saprophyticus and
descriptions of three new species: Staphylococcus cohnii, Staphylococcus haemolyticus, and Staphylococcus xylosus. Inter. J. Syst. Bact., 25: 50-61, 1975. 15) Kloos, W.E. & Schleifer, K.H.: Isolation and characterization of staphylococci from human skin. II. Descriptions of four new species: Staphylococcus warneri, Staphylococcus capitis, Staphylococcus hominis, and Staphylococcus simulans. Inter. J. Syst. Bact., 25: 62-79, 1975. 16) Kloos, W.E., Schleifer, K.H. & Smith, R. F.: Characterization of Staphylococcusciuri sp. nov. and its subspecies. Inter. J. Syst. Bact., 26: 22-37, 1976. 17) Hajek, V.: Staphylococcus intermedius, a new species isolated from animals. Inter. J. Syst. Bact., 26: 401-408, 1976. 18) Devriese, L.A. et al.: Staphylococcus hyicus (Sompolinsky 1953) comb. nov. and Staphylococcus hyicus subsp. chromogenes subsp. nov. Inter. J. Syst. Bact., 28: 482-490, 1978. 19) Brun, Y., Fleurette, J. & Ferey. F.: Micromethod for biochemical identification of coagulase-negative staphylococci. J. Clin. Microbiol., 8: 503-503, 1978. Species Classification, Pathogenicity and Antibiotic-susceptibility of Staphylococcal Isolates from Clinical Specimens Toshiro OKUDA*, Yukio HIROSAWA** & Hiroshi ZEN-YOJI *,** *Department of Microbiology, School of Health Science, Kyorin University, Hachioji, Tokyo, Japan **Department of Clinical pathology, School of Medicine, Kyorin University, Mitaka, Tokyo, Japan specimens at Bacteriological A total of 863 cultures of staphylococci were obtained from various clinical August, 1980. These isolates Laboratory in Kyorin University Hospital, during a period from March through were composed of 212 of S. aureus (24.6%) and 649 cultures of coagulase-negative staphylococci (75. 2%). Coagulase-negative staphylococci were subjected to species classification by criteria of Kloos & Schleifer. As a result, out of 649 isolates 90 wer e isolated from each specimen of blood, cerebro-spinal fluid, pus and ascites, and also urine with the coccal number more than 105 CFU/ml. These 90 isolates could be classified into 9 species except those of S. hyicus and S. sciuri. The results suggested that most of all coagulase-negative staphylococci have pathogenicity to humans, and that S. xylosus may be an important species of staphylococcal infections in the urinary tract, since 5 of 11 urinary isolates were classified to the species. Although novobiocin susceptibility test have been carried out as an important characteristic for differentiation of S. saprophyticus from other species, in this survey, major coagulase-negative staphylococci; S. xylosus, S. saprophyticus and S. warneri, were found to be novobiocin resistant in the incidence of 5/16 (31.3%), 8/29 (27.6%) and 8/40 (20.0%) respectively. Accordingly, it seems unlikely that novobiocin resistance is a key characteristic to differentiate S. saprophyticus from other species. As to sensitivity tests of major isolates to 10 antibiotics, of 103 S. aureus 21 strains showed resistant to any Among coagulase-negative strains, S. epidermidis and S. hominis were found to be especially a high incidence of multi-drug resistance, 26/36 (72.2%) of the drugs tested, and 39 multi-resistant to 2 or more drugs. and 23/32 (71.9%) respectively. Also out of 53 strains classified to the other species, 16 were multi-resistant ones.