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R R Facklam

Publications and source records attributed to R R Facklam.

At least 109 records · Page 6Linked to original sources

Identification of Enterococcus species isolated from human infections by a conventional test scheme.

Streptococci (206 cultures) previously identified as enterococci were retrieved from storage and reidentified by using tests designed to identify species of the genus Enterococcus. Of these 188, 91% were correctly identified as Enterococcus species. Of the remaining strains, nine (4%) were unidentified and six (3%) and 3 (1.5%) were identified as Leuconostoc sp. and Lactococcus sp., respectively. Two new Enterococcus species were discovered: E. raffinosus and E. solitarius. DNA-DNA hybridizations were performed on selected strains to assure correct identification. Cultures representing 10 of the 12 Enterococcus species were among the 188 strains identified. An identification system based on the grouping of key reactions of 20 phenotypic characteristics of Enterococcus species is described.

Bacteriological Techniques↗

Enterococci highly resistant to penicillin and ampicillin: an emerging clinical problem?

Sixteen clinical isolates of ampicillin-resistant enterococci (ARE) were recovered from the microbiology laboratory of a 450-bed rehabilitation medical center from January 1981 to September 1987. These isolates were detected when a disk diffusion test using 10 micrograms of ampicillin on a blood agar plate revealed no zones of inhibition. Tube macrodilution tests yielded an MIC of greater than or equal to 16 micrograms of ampicillin per ml. None of the isolates were penicillinase producers by the chromogenic cephalosporin disk test. Ten isolates were Enterococcus faecium, four isolates were E. raffinosus, one isolate was E. gallinarum, and one isolate was not identified (lost). There were 6 male and 10 female patients. The sources of isolates were urine (n = 7), wound (n = 5), ascitic fluid (n = 2), blood (n = 2), peritoneal catheter tip (n = 1), Bartholin's cyst abscess (n = 1), rectal swab (n = 2), and pancreatic abscess (n = 1). The organism was isolated from multiple sites in 4 patients, was a pure culture isolate in 5 patients, and was part of a polymicrobial flora in 11 patients. Six patients were diabetic, and four had liver cirrhosis. All but four patients had received at least one antibiotic within 3 weeks of ARE isolation. The MICs (micrograms per milliliter) for 50 and 90% of isolates tested, respectively, were as follows: ampicillin, 64 and 64; penicillin, 128 and greater than 128; vancomycin, 1 and 2; gentamicin, 4 and 16; ciprofloxacin, 1.6 and 3.2; imipenem, 128 and greater than 128; and daptomycin (LY146032), 1.6 and 6.4. ARE may be an emerging pathogen in the hospitalized patient population.

Adolescent↗

A day care-based study of the efficacy of Haemophilus b polysaccharide vaccine.

To assess the efficacy of the Haemophilus b polysaccharide vaccine following licensure and to evaluate the risk of Haemophilus influenzae type b (Hib) disease in the week following vaccination, we conducted a day care-based case-control efficacy study using cases of invasive Hib disease ascertained through active surveillance in areas with a total population of 34 million. For each patient 18 to 59 months old, up to three 18- to 59-month-old controls were chosen from the same day care classroom. Using conditional logistic regression, the vaccine efficacy was estimated to be 45% (95% confidence interval = -1% to 70%) and did not change significantly after accounting for potential biases. In addition, three (3%) of 104 patients vs five (2%) of 207 controls were vaccinated within seven days before the patients' dates of admission (odds ratio = 1.8, 95% confidence interval = 0.3 to 10.2), which does not suggest an increased risk of Hib disease in the week following immunization. This study suggests that the efficacy of the currently used HBPV is less than expected from previous studies and points out the usefulness of case-control studies for monitoring vaccine efficacy following licensure.

Bacterial Capsules↗

Recovery of resistant enterococci during vancomycin prophylaxis.

We report a case of a patient undergoing hemodialysis who developed a wound infection and subsequently bacteremia with a strain of vancomycin-resistant enterococcus identified as Enterococcus gallinarum. He had been receiving vancomycin prophylaxis before developing these infections. Both isolates were susceptible to ampicillin, rifampin, teicoplanin, and daptomycin (LY146032).

Aged↗

Rapid group A streptococcal antigen detection kit: effect on antimicrobial therapy for acute pharyngitis.

Newly introduced rapid diagnostic tests for group A streptococcal pharyngitis should facilitate appropriate antimicrobial use in patients with group A streptococcal pharyngitis. Because of high rates of acute pharyngitis in Tuba City, AZ, at the Navajo Indian reservation, the use of rapid diagnostic test was prospectively evaluated. The sensitivity and specificity of the test was measured and changes in physician prescribing patterns attributable to use of the test were correlated. Of 320 patients with pharyngitis enrolled during the present 3-week study, 86 met the study's definition of a patient with streptococcal pharyngitis and 163 met the study's definition of a patient with nonstreptococcal pharyngitis. The rapid test was 62.8% sensitive and 96.9% specific in identifying patients from whom group A streptococci were isolated. Although treatment of patients with streptococcal pharyngitis at the time of the first visit increased from 36.5% in a retrospective sample to 72.5% during the study, treatment of patients in whom cultures were negative remained the same. Further analyses showed that physicians tended to treat patients with signs characteristic of streptococcal pharyngitis and, as the study progressed, to rely less on negative rapid test results as a reason to withhold antimicrobial agents. It was concluded that rapid tests with good specificity but limited sensitivity may improve treatment of patients with streptococcal pharyngitis by allowing earlier specific therapy. A more sensitive test with a higher negative predictive value would be necessary to prevent treatment of persons with nonstreptococcal pharyngitis.

Adolescent↗

Group A beta-hemolytic streptococcal skin infections in a US meat-packing plant.

In 1985, the second reported outbreak of group A beta-hemolytic streptococcal (GABHS) skin infections among US meat packers was recognized at an Oregon meat-packing plant. All 69 plant workers were interviewed and examined for the presence of pustular, draining, or inflamed lesions. During a three-month period, 44 episodes of skin infection occurred in 32 workers, all but four of whom worked in boning or killing areas. Acquiring infection was associated with job category (relative risk [RR], 5.7; 95% confidence intervals [CI], 2.9 to 11.3) and having at least two hand lacerations (RR adjusted for occupation, 6.2; 95% CI, 3.0 to 12.5). Group A beta-hemolytic Streptococcus (18), Staphylococcus aureus (12), or both (20) were isolated from 70 lesions cultured. Meat is suspected as a vehicle of transmission because cultures of two meat specimens contained the same GABHS strain as did 24 isolates from patients. Increasing reports of GABHS skin infections in meat packers suggest that this occupational risk may be more common than is realized.

Abattoirs↗

Susceptibility of relatively penicillin-resistant Streptococcus pneumoniae to newer cephalosporin antibiotics.

Antimicrobial susceptibilities were performed at the Centers for Disease Control on 3400 Streptococcus pneumoniae isolates that were collected during a national survey of serotype-distribution of pneumococci found in normally sterile body fluids. The results showed 126 isolates (3.7%) to be relatively resistant to penicillin (RPR). The RPR strains were tested for susceptibility to cefuroxime, ceftriaxone, cefotaxime, cefamandole, cefaclor, ceftazidime, and moxalactam. These newer generation cephalosporin drugs were tested either because of their ability to penetrate into the cerebrospinal fluid (CSF) or for their activity against pneumococci. Three hundred ninety-one pneumococci were tested with 179 resistant to at least one antimicrobial. The RPR strains were not categorically resistant to the cephalosporins but were fourfold more resistant to them than were the penicillin-susceptible strains. The three most effective antimicrobials in the study for RPR were cefuroxime, cefotaxime, and ceftriaxone [corrected]. Each gave MICs that were attainable in CSF for RPR. Fifty percent of the RPR were inhibited by 0.06 mg/ml and 90% by 0.25 micrograms/ml of these antimicrobials. The least effective were cefaclor, moxalactam, and ceftazidime.

Cephalosporins↗

Specificity study of kits for detection of group A streptococci directly from throat swabs.

A total of 78 Streptococcus strains, 15 Staphylococcus strains, and 2 Stomatococcus strains were used to test the specificity of 18 different antigen detection systems for group A streptococci and five products that detect a specific enzyme associated with group A streptococci. All streptococcal strains possessing the group A antigen were correctly identified with 31 different lots of reagents in the 18 antigen detection systems. The specificities of the 31 different lots of reagents ranged between 88.5 and 100%. A limited number of nonspecific reactions were observed with Enterococcus gallinarium, group C Streptococcus strain C23, and Staphylococcus aureus F49 and Cowan 1. The antigen detection kits that used enzymes as the extraction reagent gave slightly more specific results than did the kits that used chemical extraction reagents. The reagents in the five kits designed to detect the enzyme pyroglutamic acid arylamidase in Streptococcus pyogenes reacted positively with S. pyogenes (group A streptococcus); however, the reagents also reacted positively with all group D enterococcal streptococci and with about half of the staphylococcal strains treated. The nonspecificity of tests based on pyroglutamic acid arylamidase detection would seem to limit the usefulness of these kits with mixed cultures.

Agglutination Tests↗

Separation of Haemophilus influenzae type b subtypes by numerical analysis.

Outer membrane proteins (OMPs) were prepared from 20 previously established subtypes of Haemophilus influenzae type b. Proteins were separated by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis (11% acrylamide). Each lane in the gels contained two internal molecular weight standards. One central lane contained a range of molecular weight standards, which were used to calculate a molecular weight curve for each gel. Migration distances of the OMPs were determined with a soft laser-scanning densitometer, and the distances were normalized by using the mean migration distances of the internal standards. The protein patterns of all subtypes were compared by a recently described method (B.D. Plikaytis, G.M. Carlone, and B.B. Plikaytis, J. Gen. Microbiol. 132:2653-2660, 1986). All subtypes could be differentiated by this method. The ability to store and compare numerous OMP patterns from different isolates of H. influenzae type b, separated with a single homogeneous polyacrylamide gel, will facilitate the continued development of a subtyping system based on these proteins.

Bacterial Outer Membrane Proteins↗

Neonatal enterococcal sepsis: case-control study and description of an outbreak.

An increased incidence of neonatal sepsis caused by Group D streptococci, specifically enterococci (GDE), during a recent 6-month period prompted a 5-year review of enterococcal sepsis in our neonatal intensive care unit. Sixteen episodes occurred in 14 babies. GDE accounted for 8 of 19 (42%) episodes of neonatal bacteremia during the epidemic period vs. only 8 of 159 (5%) episodes during the remaining 4.5 years (endemic period) (P less than 0.001). Blood isolates were all identified as Streptococcus faecalis. A combination of three strain-typing methods successfully distinguished the epidemic organisms from endemic nursery strains of GDE and from "background" GDE flora in the hospital. Nursery isolates were all susceptible to ampicillin, intermediate or resistant to the aminoglycosides and variably resistant to the newer cephalosporins. There were no differences in antibiotic susceptibilities of the GDE or in characteristics of the patients that were unique to the epidemic. Neonates with GDE sepsis had a mean birth weight of 913 g, a mean gestational age of 27 weeks and a mean age of onset of sepsis of 8.5 weeks. Twenty-five controls, matched for birth weight and admission date, were identified. Significant differences (P less than 0.05) between cases and controls included: use of a nonumbilical central line (71 vs. 32%); days central line in place (26.5 vs. 6.5 days); and bowel resection (29 vs. 4%). This is the first reported outbreak of S. faecalis sepsis in neonates. GDE are important nosocomial pathogens that must be considered in late onset neonatal sepsis.

Cross Infection↗

Streptococcal perianal disease in children.

From October 1985 through June 1986, 31 children in a single pediatric practice were treated for perianal signs and symptoms associated with growth of group A beta-hemolytic streptococci from perianal cultures. Signs and symptoms included perianal dermatitis (90%), perianal itching (78%), rectal pain (52%), and blood-streaked stools (35%). Ages ranged from 7 months to 8 years mean 4.25 +/- 1.8 years). There were 24 boys (77%) and seven girls (23%). The 31 cases occurred in 19 families. Intrafamily spread was only to siblings and occurred in 50% of the possible situations. Direct perianal antigen studies had a sensitivity of 89% for predicting positive cultures. Four different T types of group A streptococci were isolated from these cases, but the T type within each family outbreak was identical except in one case. When group A streptococci were found in the pharynx (64% of patients), the T type of the pharyngeal and perianal isolates were identical. Treatment was usually with oral penicillin. Relapses occurred in 39%. Signs of cellulitis were absent in all 31 cases and, therefore, we suggest that the nomenclature for this entity be changed from streptococcal perianal cellulitis to streptococcal perianal disease.

Anti-Bacterial Agents↗

Primary invasive Haemophilus influenzae type b disease: a population-based assessment of risk factors.

We performed a population-based case-control study of risk factors for primary invasive Haemophilus influenzae type b (Hib) disease in metropolitan Atlanta from July 1, 1983, through June 30, 1984. Active surveillance identified 102 cases in children less than 5 years of age, 89 of whom lived in households with telephones. We used random digit dialing to select 530 controls who were postmatched to cases by age. Multivariate analysis showed a significant association between Hib disease and two independent exposure factors, household crowding (odds ratio (OR) 2.7, 95% confidence limits (CL) 1.3 to 5.6) and day-care attendance. For day-care attendance, relative risk was highest in 2- to 5-month-old infants (OR 17.7, 95% CL 5.8 to 54.4) and declined to 9.4 (4.3 to 20.9) at ages 6 to 11 months, 5.0 (2.7 to 9.3) at 12 to 23 months, 2.7 (1.3 to 5.5) at 24 to 35 months, and 1.4 (0.5 to 4.0) in 36- to 59-month-old children. Fifty percent of all invasive Hib disease that occurred during the study period was attributable to exposure to day-care; the attributable risk for household crowding was 18%. Dose-response effects were observed for hours per week of day-care attendance and extent of household crowding. Breast-feeding was protective for infants less than 6 months of age (OR 0.08, 95% CL 0.01 to 0.59). After controlling for socioeconomic and other confounding factors, we could demonstrate no effect of black race on cumulative risk of invasive Hib disease. Our study defines high-risk groups and provides a population-based model of the interrelationship between risk factors associated with invasive Hib disease.

Age Factors↗

Viridans streptococcal endocarditis: clinical, microbiological, and echocardiographic correlations.

Infections caused by species within the viridans streptococci have been associated with different clinical characteristics. We studied 36 patients with viridans streptococcal endocarditis. Complications were seen in 10 (32%) of 31 patients with native valve endocarditis and four (80%) of five with prosthetic valve endocarditis and included death in two, valve replacement in six, persistent infection in three, emboli in two, and congestive heart failure in nine. Two-dimensional echocardiograms demonstrated vegetations in 26 (72%) of 36, flail mitral valves in seven, disruption of aortic valve prosthesis in one, and perivalvular abscesses in three (two Streptococcus sanguis I and one Streptococcus intermedius I). All twelve patients with native valve endocarditis who suffered complications had vegetations detected by two-dimensional echocardiography, whereas seven patients with native valve endocarditis without vegetations, as detected by two-dimensional echocardiography, had no complications (P = .03). We found no significant correlation between streptococcal species and clinical outcome. To confirm our identifications, we sent 16 identical viridans streptococcal endocarditis isolates to five institutions; only three of 16 were identified as the same species by all five institutions. We conclude that viridans streptococcal endocarditis can be associated with a virulent clinical course and that there is marked variability in species designations of individual strains by different laboratories.

Adolescent↗

New test system for identification of Aerococcus, Enterococcus, and Streptococcus species.

A total of 244 strains of Aerococcus, Enterococcus, and Streptococcus species were tested by the RapID STR system (Innovative Diagnostic Systems Inc., Atlanta, Ga.) for identification. Strains were identified without additional tests or with additional conventional tests suggested by the IDS compendium manual. Our data indicate that the RapID STR system identifies 89% of the beta-hemolytic Streptococcus species if serological procedures are used in conjunction with the rapid physiological procedures. Of the group D streptococci, 98% of the Enterococcus species and 100% of the group D non-Enterococcus species were correctly identified. Of the commonly occurring viridans group Streptococcus species, 93% were correctly identified, and 79% of the less frequently occurring viridans group Streptococcus species were correctly identified. All of the Streptococcus pneumoniae and Aerococcus strains tested were correctly identified.

Humans↗

Pneumococcal vaccine efficacy in selected populations in the United States.

The efficacy of pneumococcal vaccine in groups of patients in the United States at high risk for pneumococcal disease was estimated by comparing distributions of serotypes of Streptococcus pneumoniae isolated from vaccinated and unvaccinated persons. Between May 1978 and March 1984, 187 blood isolates and 62 cerebrospinal fluid isolates from vaccinated patients, and 1447 blood isolates and 191 cerebrospinal fluid isolates from unvaccinated patients were serotyped at the Centers for Disease Control. The study did not include patients who were less than 2 years old or who had Hodgkin's disease, multiple myeloma, or immunoglobulin deficiency. In patients with bacteremic disease, the overall efficacy of pneumococcal vaccine was estimated at 64% (95% confidence limits, 47% to 76%); efficacy did not differ significantly with age. In persons over 65 years of age with diabetes mellitus, chronic heart disease, pulmonary disease, or no underlying illnesses, efficacy was 61% (95% confidence limits, 1% to 85%). These findings support the use of pneumococcal vaccine in selected populations in the United States.

Adolescent↗

Outbreaks of group A streptococcal abscesses following diphtheria-tetanus toxoid-pertussis vaccination.

Two outbreaks of group A streptococcal abscesses following receipt of diphtheria-tetanus toxoid-pertussis (DTP) vaccine from different manufacturers were reported to the Centers for Disease Control (CDC) in 1982. The clustering of the immunization times of cases, the isolation of the same serotype of Streptococcus from all cases in each outbreak, and the absence of reported abscesses associated with receipt of the same lots of vaccine in other regions of the country, suggest that each outbreak was probably caused by contamination of a single 15-dose vial of vaccine. The preservative thimerosal was present within acceptable limits in unopened vials from the same lot of DTP vaccine in each outbreak. Challenge studies indicate that a strain of Streptococcus from one of the patients can survive up to 15 days in DTP vaccine at 4 degrees C. Contamination of vials during manufacturing would have required survival of streptococci for a minimum of 8 months. Preservatives in multidose vaccine vials do not prevent short-term bacterial contamination. Options to prevent further clusters of streptococcal abscesses are discussed. The only feasible and cost-effective preventive measure now available is careful attention to sterile technique when administering vaccine from multidose vials.

Abscess↗