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R R Facklam

Publications and source records attributed to R R Facklam.

At least 127 records · Page 7Linked to original sources
PubMed1984

Evaluation of the Directigen Group A Strep test kit.

The Directigen Group A Strep test kit (Hynson, Wescott, and Dunning, Baltimore, Md.) was tested for its ability to detect group A streptococci directly from 147 throat swabs. The results were compared with results from conventional culture and Lancefield serological grouping tests. The data showed that 121 of 124 culture-negative throat specimens were also Directigen negative (98%) and that 21 of 23 culture-positive specimens were Directigen positive (91%). If specimens that provided less than 10 colonies per plate of beta-hemolytic streptococci were eliminated, all of the culture-positive specimens were Directigen positive. Positive or negative results were available within 65 to 70 min of testing. The Directigen method is relatively simple to perform and easy to interpret and provides accurate assessment of the presence or absence of group A streptococci in throat swabs, with little or no cross-reactivity with other beta-hemolytic groups.

Antigens, Bacterial↗
PubMed1984

Evaluation of the Rapid Strep system for the identification of clinical isolates of Streptococcus species.

A total of 247 strains of streptococci isolated from humans were tested for identification in the Rapid Strep system. The identification rates and identification levels were different for each Streptococcus species. Our data indicate that the Rapid Strep system will identify nearly all 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 enterococci and 95% of the non-enterococci were correctly identified. Of the commonly occurring viridans species, 85% were correctly identified, but only 10% of the less frequently occurring viridans species were identified. A total of 90% of the Streptococcus pneumoniae and 60% of the Aerococcus strains were correctly identified.

Humans↗
PubMed1984

Streptococcus faecium outbreak in a neonatal intensive care unit.

An outbreak of bacteremia and meningitis in a neonatal intensive care unit is described. Seven cases occurred in premature infants with severe underlying diseases. An epidemiological investigation failed to document the reservoir of the epidemic strain but suggested that its transmission among the infants was via the hands of hospital personnel. All patients had nasogastric tubes and multiple intravascular devices, and the portal of entry may have been either the gastrointestinal tract or the sites of the intravascular devices. Conventional biotyping of isolates failed to differentiate between isolates from infected patients and isolates recovered from prevalence surveys and from the environment. However, rapid identification systems (API-20S [Analytab Products, Plainview, N.Y.] and the AutoMicrobic system [Vitek Systems, Inc., Hazelwood, Mo.]) were able to distinguish isolates recovered from infected patients and hands of hospital personnel from isolates recovered during prevalence and environmental surveys and 29 isolates from widespread geographical areas. This is the first known report of a nosocomial neonatal outbreak of bacteremia and meningitis due to Streptococcus faecium; it underscores the importance of identifying streptococci to species level.

Cross Infection↗
PubMed1983

The development by the Centers for Disease Control of a specification for streptococcal serogrouping kits and its application to Streptex and to the Phadebact Streptococcus Test.

A Centers for Disease Control (CDC) specification for evaluating commercially produced streptococcal agglutination reagents was developed and used to test Streptex and Phadebact Streptococcus Test kits. Evaluation methods and performance requirements were based on product claims made in the package labelling. Except for the reagent for Streptococcus group D, reagents of both systems identified 100% of the blind-coded reference strains when follow-up methods were done according to the manufacturers' directions. Streptex group D reagent did not identify all group D strains, but the manufacturer instructed the user to test with other methods in certain circumstances. The interaction of personnel of the Center for Infectious Diseases (CID), CDC, with commercial producers and consumers in a pre-market evaluation program is described.

Centers for Disease Control and Prevention, U.S.↗
PubMed1983

Rapid identification of enterococci.

A 4-h method was devised to differentiate the non-beta-hemolytic streptococci into three categories: enterococci, group D nonenterococci, and viridans streptococci. All of the Streptococcus faecalis, 90% of the Streptococcus faecium (enterococci), and 96% of the Streptococcus bovis biotype I (group D nonenterococci) cultures were correctly identified by the 4-h method. The less commonly isolated group D cultures had lower rates of correct identification by this method. None of the viridans streptococci was identified incorrectly.

Humans↗
PubMed1982

Foodborne outbreak of group G streptococcal pharyngitis.

An outbreak of pharyngitis associated with beta-hemolytic streptococci of Lancefield group G occurred among persons who had attended a convention that was held June 21-24, 1979, in a Florida hotel. Seventy-two (31 per cent) of 231 interviewed conventioneers were ill. Group G streptococci were isolated from the throats of 10 (63 per cent) of 16 persons with pharyngitis and 1 (2 per cent) of 41 persons without pharyngitis (p less than 10(-5)). Antistreptolysin O titers in convalescent-phase serum samples from persons with pharyngitis were significantly higher than those from age-matched controls. Fifty-seven (51 per cent) of 111 conventioneers who had attended a convention luncheon developed pharyngitis compared with 12 (10 per cent) of 117 persons who did not (p less than 10(-9)). All persons who had attended the luncheon and had become ill had eaten a chicken salad served at the luncheon. Their median incubation period was two days. The cook who had prepared this chicken salad developed pharyngitis after the luncheon and had a throat culture positive for group G streptococci. No instances of rheumatic fever were identified and secondary illness in household contracts was rare. This outbreak indicates that group G streptococci can cause outbreaks of pharyngitis similar to those caused by group A streptococci and suggests that penicillin therapy and prophylaxis may not be needed.

Animals↗
PubMed1982

Type-specific immunity and pharyngeal acquisition of group A Streptococcus.

A prospective study of spread of M-type 1, 2, 13, 14, 25 and 60 group A Streptococcus in 64 families in Qalyub, Egypt, in 1972-1974 showed that type-specific serum bactericidal antibody does not protect against pharyngeal acquisition of homologous organisms. The presence of type-specific antibody also does not appear to affect duration of carriage of the organism. Type-specific immunity must be mediated in another way, such as by local antibody or trough prevention of infection (as evidenced by a host response) following acquisition. This study also confirms the observations of others that administration of penicillin lowers the probability that a person who acquires group A Streptococcus will develop type-specific antibody.

Antibodies, Bacterial↗
PubMed1982

Presumptive identification of streptococci with a new test system.

A test is described that could replace bacitracin susceptibility for presumptive identification of group A streptococci as well as 6.5% NaCl agar tolerance for presumptive identification of enterococcal streptococci. The L-pyrrolidonyl-beta-naphthylamide test, based on hydrolysis of pyrrolidonyl-beta-naphthylamide, was used in conjunction with the CAMP and bile-esculin tests to presumptively identify the streptococci. Among the beta-hemolytic streptococci; 98% of 50 group A, 98% of 46 group B, and 100% of 70 strains that were not group A, B, or D were correctly identified by the new presumptive test scheme. Among the non-beta-hemolytic streptococci; 96% of 74 group D enterococcal, 100% of 30 group D nonenterococcal, and 82% of 112 viridans strains were correctly identified by the new presumptive test scheme.

Bacitracin↗
PubMed1981

Transmission of group B streptococci. Traced by use of multiple epidemiologic markers.

During a three-week period, septicemia caused by group B Streptococcus, serotype III, developed in four infants born at a community hospital. The first infant had early-onset disease; late-onset disease that appeared, from epidemiologic data, to be nosocomial developed in the other three infants. Bacteriophage typing and antimicrobial susceptibility testing confirmed the relatedness of the isolates. A prospective study designed to differentiate between vertical and nosocomial transmission of group B Streptococcus showed that of 82 infants, 21 (26%) were culture-positive during their hospitalization, and nine of these infants (43%) had been culture-negative at birth. Although serotype III strains were recovered from four of nine infants with apparently nosocomial acquisition, none of the isolates displayed an antibiogram or bacteriophage type similar to that of the isolates involved in the recent cluster. Bacteriophage typing and antimicrobial susceptibility testing in addition to the use of serotyping may be helpful in epidemiologic studies of group B Streptococcus.

Bacteriological Techniques↗
PubMed1981

Synergism, killing kinetics, and antimicrobial susceptibility of group A and B streptococci.

The susceptibility of 110 group A and 179 group B streptococci to 25 antimicrobics was tested by broth microdilution and agar disk diffusion tests. Representative strains were used in killing kinetics, penicillin-gentamicin synergy, and minimal bactericidal concentration tests. Group A streptococci were more susceptible than group B streptococci to 17 of the 25 antimicrobics tested. Group A and B streptococci were killed at the same rate if the amount of penicillin used was equivalent to their respective penicillin minimal inhibitory concentrations. Synergism was demonstrated for both group A and B streptococci when penicillin was used at concentrations equal to each respective minimal inhibitory concentration and subinhibitory concentration of gentamicin. This synergy could be demonstrated best using minimal bactericidal concentrations obtained by culturing 3- and 6-h cultures from the microdilution checkerboard tests rather than from 24-h subcultures. A greater synergistic effect was achieved by adding penicillin first and then adding gentamicin rather than in the reverse order, or simultaneously.

Anti-Bacterial Agents↗
PubMed1981

Improved streptococcal grouping antisera containing polyethylene glycol.

Antisera to streptococcal groups A through G containing 4% polyethylene glycol 6000 were prepared and evaluated. Seventy strains of homologous and heterologous beta- and non-beta-hemolytic streptococci were included in the evaluation. Homologous reactions were determined against extracts prepared by four extraction methods: hot hydrochloric acid (Lancefield) extraction, autoclave extraction, hot formamide extraction, and nitrous acid extraction. Enhancement of the precipitin reaction in the presence of polyethylene glycol 6000 permitted a fourfold dilution of all antisera for use in the capillary precipitin test. At this dilution, the potency of the antisera exceeded requirements established for these reagents.

Cross Reactions↗
PubMed1981

Extraction of group A streptococcal M protein with nitrous acid.

Specific precipitating and opsonic neutralizing antigens were identified in dilute-nitrous acid extracts of group A streptococci. This was done by decreasing the temperature and time of exposure of the streptococcal cells to the nitrous acid. Ninety percent of 31 strains of group A streptococcal dilute-nitrous acid extracts formed precipitin lines of identity with conventional Lancefield extracts of the same group A streptococci.

Antigens, Bacterial↗
PubMed1980

Pneumococcal disease after pneumococcal vaccination: an alternative method to estimate the efficacy of pneumococcal vaccine.

Trials of pneumococcal vaccine in healthy young adult populations suggest 75 to 95 per cent type-specific efficacy. Trials have not been done, however, in groups for which pneumococcal vaccine is currently recommended in the United States. To assess efficacy in the immunocompromised groups now receiving the vaccine, we compared serotypes of 35 isolates of Streptococcus pneumoniae isolated from blood or cerebrospinal fluid one month or longer after the patient had received commercially available pneumococcal vaccine with serotypes of 392 isolates from unvaccinated persons surveyed in a study of the nationwide distribution of pneumococcal serotypes. Proportions of infections with vaccine serotypes were unexpectedly similar. An alternative approach to estimation of vaccine efficacy suggested an average efficacy of 36 per cent in persons of all ages. The estimated efficacy was lowest in children two to 10 years old (less than or equal to 0 per cent) and in persons with preexisting diseases that are thought to predispose to pneumococcal disease (less than or equal to 0 per cent), and highest in the group over 10 years old (60 per cent). The possibility that efficacy is low in high-risk, immunocompromised populations makes it important to evaluate clinical efficacy and not just serum antibody responses in such groups.

Adolescent↗
PubMed1980

Heterogeneity of group A type-specific antibodies.

Extracting type 6 group A streptococcai with dilute nitrous acid releases an antigen that exhibits type-specific precipitating properties with anti-M6 serum but fails to neutralize the type-specific bactericidal reaction or to absorb the bactericidal antibody from anti-M6 serum. These studies suggest that the precipitating and antiphagocytic properties of the M protein are attributable to different antigenic determinants. The antigenic determinant responsible for bactericidal antibody is more sensitive to the deleterious effect of nitrous acid than is the moiety responsible for the precipitin reaction. Use of the indirect fluorescent technique with anti-M sera absorbed with lyophilized nitrous acid extracts permits the possible differentiation of the two M-protein determinants in situ on the surface of streptococcal cells.

Antibodies, Bacterial↗