Identification, clinical distribution, and susceptibility to methicillin and 18 additional antibiotics of clinical Staphylococcus isolates: nationwide investigation in Italy

Abstract

A multicentric study of clinical Staphylococcus isolates was performed by seven operative units working in different areas of Italy. Over a 6-month period, a total of 3,226 staphylococci, isolated from in-and outpatients, were identified and tested for antimicrobial susceptibility by a protocol agreed upon by all units. On the basis of their bacteriolytic-activity patterns and other conventional tests, the isolates were identified by lyogroups, which closely correlate with human Staphylococcus species. Lyogroup I (Staphylococcus aureus) and lyogroup III (Staphylococclus capitis) were the most and the least frequently isolated staphylococci, respectively. Significant differences depending on strain origin from inor outpatients were only observed with lyogroup IV (i.e., novobiocin-resistant staphylococci), whose isolation from outpatients was three times greater than from inpatients. Lyogroup I was predominant among isolates from most clinical sources. Lyogroup IV predominated in strains isolated from the urinary tract; lyogroup V (Staphylococcus epidermidis) predominated in strains from blood, cerebrospinal fluid, and indwelling artificial devices; and lyogroup VI (Staphyloccus hominis, Staphylococcus haemolyticus, and Staphylococcus warneri) predominated in strains from bile and the male genital tract. The incidence of methicillin resistance within the different lyogroups varied from unit to unit, suggesting epidemiological differences among different hospitals and different geographical areas. On the whole, methicillin resistance was more frequent in coagulase-negative staphylococci than in S. auirelus and ranged from 19% for lyogroups I and III * Corresponding author. month period were identified and tested for antimicrobial 838

Multiple-locus VNTR Analyses of Methicillin-resistantStaphylococcus aureusfrom Jamaica

“…With a low resistance rate of 6%, chloramphenicol shows similar results to other studies: 10%, 13 5%, 27 10.7%, and 4.9% resistance. 28 Result for rifampicin, with a resistance rate of 7%, is at the lower end when compared to other reports (3%, 29 18%, 22 and 53% 30 ), although higher resistance rates of rifampicin resistance in MRSA might be attributable to the treatment of tuberculosis.…”

Antimicrobial resistance of Staphylococcus aureus: genetic basis.

“…During the late 1970s and early 1980s, strains of S. aureus resistant to multiple antibiotics including methicillin and gentamicin were increasingly responsible for outbreaks of hospital infections in countries around the world, e.g., Argentina (440), Austria (472), Australia (152,234,376,377,508), Belgium (558), Denmark (133,414), Republic of Ireland (63,64,192), England (44,393,449), France (125,166), East and West Germany (339,549), Greece (151), Italy (525), Japan (242), and the United States (94, 184,437,538). In many instances, these outbreaks were associated with indi-vidual wards or units, with neonatal (152,183,393), intensive care (498), and burns units (17,42) being particularly susceptible.…”

Crowdsourced Data Indicate Widespread Multidrug Resistance in Skin Flora of Healthy Young Adults

“…For S. capitis , we calculated 69% penicillin resistance, 47% oxacillin resistance, and 60% erythromycin resistance. A different source ( 45 ) reports tetracycline resistance in S. capitis at 25% in clinical isolates from Italy. The resistance levels reported here for oxacillin and erythromycin are substantially lower; even the “likely-to-be-inflated” ABR frequency for penicillin reported here is much lower than that observed in clinical isolates.…”