Methicillin-resistant coagulase-negative staphylococcal osteomyelitis and its relationship to broad-spectrum oral antibiosis in a predominantly diabetic population.
Awareness of the virulence of coagulase-negative Staphylococci, previously regarded as saprophytes with minimal pathogenicity, has steadily increased. Eighty-seven individual patients diagnosed with acute osteomyelitis, as confirmed by microbiologic and pathologic analysis, were included in this study. Of these patients, 82% (71/87) were known to have diabetes mellitus. The prevalence of coagulase negative Staphylococcus was 40% (35/87) in deep bone cultures, 63% (22/35) of which were methicillin resistant. When the coagulase negative Staphylococcus group was assessed for prior long-term (> 2 week) oral antibiotic treatment with ciprofloxacin, it was found that 54% (12/22) of the methicillin-resistant coagulase-negative Staphylococcal infected patients had received such treatment, compared with 15% (2/13) of patients with methicillin-sensitive coagulase-negative Staphylococcal osteomyelitis (p < 0.034). When the group was analyzed for prior long-term antibiotic treatment with amoxicillin/clavulanate, 23% (5/22) of the methicillin-resistant patients had received oral amoxicillin/clavulanate, compared with 23% (3/13) of patients with methicillin-sensitive coagulase-negative Staphylococcal osteomyelitis (p > 0.05). Prevalence of polymicrobial infections, which constituted 29% (25/87) of all individual patients, was also analyzed. Of those patients with coagulase-negative isolates, 29% (10/35) were polymicrobial (p > 0.05). The results from this study suggest that infections of bone caused by coagulase-negative Staphylococci are associated with a high prevalence of methicillin resistance. This study also raises the question of whether injudicious prolonged use of ciprofloxacin may, in fact, promote proliferation of resistant organism strains.
Armstrong
D G
DG
Department of Podiatric Surgery, Monsignor Clement Kern Hospital for Special Surgery, Warren, Michigan, USA.
Lanthier
J
J
Lelievre
P
P
Edelson
G W
GW
D000208:Acute Disease; D000368:Aged; D000658:Amoxicillin / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D002939:Ciprofloxacin / Q000627:therapeutic use; D019818:Clavulanic Acid; D002969:Clavulanic Acids / Q000627:therapeutic use; D003030:Coagulase / Q000378:metabolism; D048909:Diabetes Complications; D003920:Diabetes Mellitus / Q000382:microbiology*; D005260:Female; D006801:Humans; D008297:Male; D016106:Methicillin Resistance; D008875:Middle Aged; D010019:Osteomyelitis / Q000150:complications / Q000188:drug therapy* / Q000382:microbiology*; D013203:Staphylococcal Infections / Q000188:drug therapy*; D013210:Staphylococcus / Q000187:drug effects
D000900:Anti-Bacterial Agents; D002969:Clavulanic Acids; D003030:Coagulase; D019818:Clavulanic Acid; D002939:Ciprofloxacin; D000658:Amoxicillin