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G P Carter

Publications and source records attributed to G P Carter.

10 recordsLinked to original sources
PubMed1992

Pyrazinamidase, CR-MOX agar, salicin fermentation-esculin hydrolysis, and D-xylose fermentation for identifying pathogenic serotypes of Yersinia enterocolitica.

We evaluated several simple laboratory tests that have been used to identify pathogenic serotypes of Yersinia enterocolitica or to indicate the pathogenic potential of individual strains. A total of 100 strains of Y. enterocolitica were studied, including 25 isolated during five outbreak investigations, 63 from sporadic cases, and 12 from stock cultures. The pyrazinamidase test, which does not depend on the Yersinia virulence plasmid, correctly identified 60 of 63 (95% sensitivity) strains of pathogenic serotypes and 34 of 37 (92% specificity) strains of nonpathogenic serotypes. Salicin fermentation-esculin hydrolysis (25 degrees C, 48 h) correctly identified all 63 (100% sensitivity) strains of the pathogenic serotypes and 34 of 37 (92% specificity) strains of the nonpathogenic serotypes. The results of the pyrazinamidase and salicin-esculin tests disagreed for only 7 of the 100 strains of Y. enterocolitica, and these would require additional testing. Congo red-magnesium oxalate (CR-MOX) agar determines Congo red dye uptake and calcium-dependent growth at 36 degrees C, and small red colonies are present only if the strain contains the Yersinia virulence plasmid. This test has proven to be extremely useful for freshly isolated cultures, but only 15 of 62 strains of pathogenic serotypes that had been stored for 1 to 10 years were CR-MOX positive. None of the 16 strains of Y. enterocolitica serotype O3 fermented D-xylose, so this test easily differentiated strains of this serotype, which now appears to be the most common in the United States. Although antisera that can actually be used to serotype strains of Y. enterocolitica are not readily available, the four simple tests described above can be used to screen for pathogenic serotypes.

Agar↗
PubMed1991

Yersinia enterocolitica O:3: an emerging cause of pediatric gastroenteritis in the United States. The Yersinia enterocolitica Collaborative Study Group.

After an outbreak of Yersinia enterocolitica infections among black children in Atlanta, a seven-hospital study was conducted to determine the importance of this pathogen in other communities with large black populations. Of 4841 stool specimens from patients with gastroenteritis examined between November 1989 and January 1990, Y. enterocolitica, Shigella, Campylobacter, and Salmonella were identified in 38, 49, 60, and 98 specimens, respectively; 34 (92%) of 37 Y. enterocolitica isolates were serotype O:3. Of the 38 patients with yersiniosis, 37 (97%) were children. Illnesses were clustered around the holidays, and 20 (62%) of 32 patients had been exposed to raw pork intestines in the 2 weeks before onset. Exposure was significantly associated with illness in a case-control study of eight patients identified at one hospital (P = .004). Infants less than or equal to 6 months old with yersiniosis were more likely to have immature-to-total neutrophil ratios greater than 0.50 than were infants of comparable age with salmonellosis (P = .02). Infrequently isolated in the past, Y. enterocolitica O:3 is emerging as an important enteric pathogen in this country, particularly among black children.

Adolescent↗
PubMed1991

Yersinia enterocolitica: a frequent seasonal stool isolate from children at an urban hospital in the southeast United States.

From 1 December 1988 through 28 February 1991, 7,290 rectal swab specimens received in our laboratory were screened for Yersinia enterocolitica. A total of 76 patients had Y. enterocolitica isolated from their stool samples. Of these patients, 59 (77.6%) were 12 months old or younger. Y. enterocolitica was second only to Salmonella spp. in this age group. Routine screening for Y. enterocolitica may be warranted in hospitals serving large pediatric populations.

Child↗
PubMed1990

Identification of the bacterium associated with haemorrhagic septicaemia in rainbow trout as Hafnia alvei.

An unidentified bacterium responsible for epizootic haemorrhagic septicaemic disease in rainbow trout was recently described. This organism exhibited some antigenic similarity to Brucella abortus and to Yersinia ruckeri and was presumed to belong to the family Enterobacteriaceae. Further biochemical characterization and DNA relatedness studies showed that pathogenic fish strains are Hafnia alvei.

Animals↗
PubMed1989

Xenorhabdus luminescens (DNA hybridization group 5) from human clinical specimens.

An unusual isolate from a human leg wound was identified as Xenorhabdus luminescens. This finding led to the discovery or isolation of four additional strains, two from blood and two from wounds. Three of the five strains were from patients in San Antonio, Tex. Three strains were studied by DNA-DNA hybridization (S1 nuclease-trichloroacetic acid method) and were 77 to 100% related to each other, 34% related to the type strain of X. luminescens, 35 to 40% related to three of Grimont's other DNA hybridization groups of X. luminescens, and 9% related to the type strain of Xenorhabdus nematophilus. The new group of five strains was designated X. luminescens DNA hybridization group 5. All five strains were very inactive biochemically and fermented only D-glucose and D-mannose. The key reactions for recognizing this new organism are yellow pigment production, negative test for nitrate reduction to nitrite, weak bioluminescence (10 to 15 min of dark adaptation is required to see the weak light produced), and a unique hemolytic reaction on sheep blood agar plates incubated at 25 degrees C. Two case histories of strains from wounds are given; these suggest that X. luminescens DNA hybridization group 5 may be a new bacterial agent that causes wound infections. The two cases of wound infection, along with the two blood isolates, suggest that the new organism is clinically significant.

Aged↗
PubMed1986

Occurrence and distribution of serotypes of the Arizona subgroup of Salmonella strains in the United States from 1967 to 1976.

The Salmonella Arizona subgroup contains gram-negative enteric bacteria that are closely related to other salmonellae biochemically, serologically, and genetically. Although the Arizona subgroup may be isolated from a wide variety of nonhuman and human sources, the arizonae are uncommonly recognized as human pathogens, and surprisingly little is known about their epidemiology. From 1967 through 1976, the Centers for Disease Control received 858 Arizona subgroup cultures from human and nonhuman sources representing 143 different serotypes in 33 somatic groups; several serotypes had not been previously reported. The 374 cultures from humans represent 71 different serotypes; extraintestinal isolates were present in 31 (44%) serotypes. Compared with data from a previous 20 years of surveillance, the proportion of Arizona subgroup strains isolated from stools, blood, and other sites was remarkably stable, but several serotypes showed marked changes in their frequency of isolation. In total, the ratio of extraintestinal to intestinal isolates was 0.37, but marked serotype-specific variation was noted, suggesting differences in virulence associated with serotype.

Amphibians↗
PubMed1983

Yersinia enterocolitica pharyngitis.

During the investigation of a large multistate outbreak of milk-borne yersiniosis, 14 patients who presented with pharyngitis had Yersinia enterocolitica isolated from the throat. Their illness was characterized by sore throat and fever without enteritis; 3 needed hospitalization. All patients tested had leukocytosis and an elevated convalescent-phase serum titer against the outbreak strain. In contrast to patients with enteritis, who were children, all patients with pharyngitis were adults. Thus, Y. enterocolitica may be responsible for some sporadic cases of pharyngitis in which the throat culture is negative for other pathogens.

Adolescent↗
PubMed1980

Increase in antibiotic resistance among isolates of Salmonella in the United States, 1967-1975.

To study temporal changes in the antibiotic resistance of Salmonella in the United States, a study design similar to that of a 1967 study was used to determine the antibiotic sensitivity of 754 human nontyphoid Salmonella isolates sent to the Center for Disease Control, Atlanta, Georgia, in 1975. The frequency of resistance to one or more of the same nine antibiotics used in both studies increased significantly during the eight years in Salmonella typhimurium (40%-59%; P = 0.004), other serotypes (14%-23%; P = 0.001), and all serotypes combined (21%-31%; P < 0.001). The increase in frequency of resistance was significant for streptomycin (P = 0.022), sulfonamides (P < 0.001), ampicillin (P < 0.001), and kanamycin (P < 0.001). No chloramphenicol-resistant isolates were found in the 1967 study, whereas six isolates (0.8%) were resistant in 1975. The frequency of strains resistant to six or more antibiotics increased greatly (0.8%-5.0%; P < 0.001). These data document a continuing increase in antimicrobial resistance among Salmonella isolates.

Ampicillin↗