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N W Luechtefeld

Publications and source records attributed to N W Luechtefeld.

11 recordsLinked to original sources
PubMed1983

Evaluation of transport media for Campylobacter jejuni in human fecal specimens.

It is not always possible to culture feces immediately, and appropriate methods for transport of human specimens, unlike those from animals, have not been fully evaluated. Therefore, we took serial subcultures in two phases from six transport media inoculated with human diarrheal stools known to be positive for Campylobacter jejuni. In phase 1, Cary-Blair medium and buffered glycerol saline did not preserve C. jejuni as well as did alkaline peptone-water (APW), modified Cary-Blair medium, thioglycolate broth (Thio), and Campy-Thio. The four best media (APW, Cary-Blair medium, Thio, and Campy-Thio) preserved 20 fecal samples with C. jejuni better at 4 degrees C (90% survival for 5 to 8 days) than at 25 degrees C (90% survival for 1.7 to 2 days). In phase 2, APW and Thio, along with four modifications of the best media in phase 1, were tested with 23 positive strains. The ranges of survival times with modified media at 25 degrees C were 1.3 to 2.2 days (90%) and 4.7 to 6.8 days (50%). APW with reducing agents preserved C. jejuni better than did APW alone, Thio plus ox bile, or Campy-Thio plus ox bile (P less than 0.05). Thio at pH 8.5 was better at preserving C. jejuni than was APW or Thio plus ox bile (P less than 0.05). If human fecal specimens cannot be refrigerated during transport or storage, we recommend the use of Thio at pH 8.5 or APW with reducing agents for preservation of C. jejuni at 25 degrees C.

Bacteriological Techniques↗
PubMed1983

Effect of incubation atmosphere and temperature on isolation of Campylobacter jejuni from human stools.

To determine the optimal conditions for isolation of Campylobacter jejuni from human fecal specimens, we compared incubation atmospheres that contained about 5, 10, and 15% oxygen with the 17% oxygen produced in candle jars and also compared incubation temperatures of 37 and 42 degrees C. At 42 degrees C, C. jejuni was isolated from all 16 specimens; however, colony sizes were larger when plates were incubated in 5 and 10% oxygen than in the other two atmospheres. At 37 degrees C some positive cultures were missed in 15% oxygen and in the candle jar. The largest colony sizes were obtained in 5% oxygen. For each atmospheric condition tested, the colonies were larger at 42 than at 37 degrees C. When incubation is done at 42 degrees C, use of a candle jar is adequate; however, at 37 degrees C candle jars should not be used for isolation of C. jejuni from human feces.

Campylobacter↗
PubMed1982

Hippurate hydrolysis by and triphenyltetrazolium tolerance of Campylobacter fetus.

A rapid test of hippurate hydrolysis and a test of tolerance to triphenyltetrazolium chloride (TTC) were studied in 315 strains of Campylobacter fetus subsp. jejuni to determine their usefulness for biotyping this organism and for distinguishing it from C. fetus subsp. intestinalis. Of the 315 strains tested, 84% hydrolyzed hippurate and 97% were resistant to TTC. Ability to hydrolyze hippurate was seen in 99% of 155 human isolates, 75% of 60 avian isolates, 100% of 41 cattle and dog isolates, 84% of 31 zoo mammal isolates, and none of 28 hog isolates. Resistance to 400 micrograms of TTC per ml was seen in 97% of the human isolates, 95% of the avian isolates, and 100% of the mammalian isolates (other than human). In no case did any of the 315 isolates of C. fetus subsp. jejuni show both lack of ability to hydrolyze hippurate and sensitivity to TTC. In contrast, all 18 strains of C. fetus subsp. intestinalis failed to hydrolyze hippurate and were sensitive to TTC. These two tests may be useful to distinguish between C. fetus subsp. jejuni and subsp. intestinalis and also to biotype strains of C. fetus subsp. jejuni.

Animals↗
PubMed1982

Comparison of atmospheres of incubation for primary isolation of Campylobacter fetus subsp. jejuni from animal specimens: 5% oxygen versus candle jar.

An atmosphere with reduced oxygen tension is required for the primary isolation of Campylobacter fetus subsp. jejuni. Therefore, we compared use of the conventional atmosphere of 5% oxygen and 8% carbon dioxide with use of a candle jar (17% oxygen and 3% carbon dioxide) for primary isolation of C. fetus subsp. jejuni from 263 positive canine, cattle, and turkey fecal or cecal specimens. At an incubation temperature of 42 degrees C, the atmosphere with 5% oxygen resulted in more Campylobacter colonies per plate (P less than 0.005) and consistently larger Campylobacter colonies (P less than 0.005) than did the candle jar, whereas the growth of interfering flora was similar. Overall, 96% of the 263 specimens were positive for C. fetus subsp. jejuni with 5% oxygen, and 90% were positive with the candle jar (P less than 0.02). More striking differences in isolation rates were seen when both the temperature and the atmosphere were varied: 5% oxygen at 42 degrees C enabled recovery of 93% of the isolates from 70 positive specimens, versus 46% recovery with the candle jar at 37 degrees C. Results with 5% oxygen at 37 degrees C were intermediate. The addition of FBP supplement (0.25% each of ferrous sulfate, sodium metabisulfite, and sodium pyruvate) to Campy-BAP selective medium made no improvement over unsupplemented medium at 42 degrees C (whether in 5% oxygen or in the candle jar), but there was significant improvement over unsupplemented medium when both media were incubated at 37 degrees in the candle jar.

Animals↗
PubMed1982

Comparison of CampyPak II with standard 5% oxygen and candle jars for growth of Campylobacter jejuni from human feces.

To determine optimal temperature and atmospheric conditions for isolating Campylobacter jejuni from fecal specimens of humans, we studied six laboratory isolates and 19 fecal specimens that were known to contain C. jejuni. We compared incubations in 5% oxygen, the CampyPak II (BBL Microbiology Systems, Cockeysville, Md.) with 6 plates per jar (CP-6) and 12 plates per jar (CP-12), and candle jars at 37 and 42 degrees C. At both temperatures, the colony sizes for the laboratory strains were larger in the 5% O2 and the CP-6 than under the other two conditions. For the primary isolations, CP-12 failed to detect one and two campylobacters at 42 and 37 degrees C, respectively, whereas the candle jar failed to detect one at 42 degrees C and four at 37 degrees C. Colony size was again larger in the 5% O2 and the CP-6. For all four atmospheric conditions tested, colonies were significantly larger at 42 degrees C than at 37 degrees C. These studies showed that incubation at 42 degrees C in either 5% O2 or the CampyPak II with six plates per jar was optimal for primary isolation of C. jejuni from fecal specimens of humans. The candle jars incubated at 42 degrees C appeared to be satisfactory for primary isolation of C. jejuni from human feces, but incubation at 37 degrees C was not acceptable.

Bacteriological Techniques↗
PubMed1982

Campylobacter enteritis in Denver.

To determine the relative importance of Campylobacter jejuni as a cause of diarrheal illness in patients coming to three hospitals in Denver, we cultured stool specimens from 2,670 patients over a two-year period. C jejuni was identified in the feces of 124 patients (4.6 percent), Salmonella from 90 (3.4 percent) and Shigella from 77 (2.9 percent). Most Campylobacter isolates were obtained in the summer months and from patients 10 to 29 years old. The illness usually lasted less than two weeks; predominant symptoms were diarrhea (98 percent), abdominal pain (88 percent) and fever (82 percent); patients with severe illness frequently had objective evidence of nonspecific colitis. Occult blood and leukocytes were present in stool specimens of 71 percent and 85 percent, respectively, of the patients tested. The duration and severity of illness led to antibiotic therapy in about half of the patients; erythromycin appeared effective. This study confirms the importance of C jejuni as a cause of enteritis; this microorganism should be sought routinely in fecal specimens from patients with diarrhea.

Adolescent↗
PubMed1981

Isolation of Campylobacter fetus subsp jejuni from zoo animals.

Over a 1-year period, 619 fecal specimens from animals at the Denver Zoo were cultured for Campylobacter fetus subsp jejuni. The organism was isolated from 35 animals, including 12 primates, 2 felids, a red panda, 13 hooved animals, 6 birds, and 1 reptile. Of 44 cultured fecal specimens from diarrheal animals, 31.8% were positive for Campylobacter, whereas only 5.6% of 575 specimens from animals without diarrhea were positive (P less than 0.001). Among 25 isolates tested, 12 serotypes were represented; several of these serotypes are commonly associated with Campylobacter enteritis in human beings. Campylobacter fetus subsp jejuni was isolated from 8% of 75 wild pigeons trapped on the zoo premises during winter months and from 26% of 75 trapped during March and April (P less than 0.01).

Alligators and Crocodiles↗
PubMed1981

Campylobacter fetus subsp. jejuni in a turkey processing plant.

Cecal cultures taken over a 1-year period from 600 turkeys at a poultry processing plant were all positive for Campylobacter fetus subsp. jejuni. Swabs of the cloaca and fresh feces were likewise all positive. Of 33 freshly dressed turkey carcases, 94% were positive before chilling in tanks of chlorinated ice and water; 34% of 83 carcasses were still positive after overnight soaking in the tanks. Increasing the chlorine content from 50 to 340 ppm (50 to 340 micrograms/ml) did not cause a decrease in the number of positive carcasses. C. fetus subsp. jejuni was isolated from wastewater gutters as well as from chutes and conveyor belts in the packaging room. Water samples from the five water treatment lagoons for the plant were all positive for C. fetus subsp. jejuni while the plant was in operation, but 4 days after the plant closed for the winter, all water samples were negative.

Animals↗
PubMed1981

Evaluation of transport and storage techniques for isolation of Campylobacter fetus subsp. jejuni from turkey cecal specimens.

Immediate culturing of fecal specimens is not always possible, and appropriate methods for transport and storage of Campylobacter fetus subsp. jejuni specimens have not been fully evaluated. Using nine techniques, we studied the survival of C. fetus subsp. jejuni in cecal specimens from infected turkeys. The organisms survived in specimens held without transport medium for 3 to 15 days (median, 9 days) at 4 degrees C, and 2 to 9 days (median, 4 days) at 25 degrees C. Only 20% of specimens frozen for 24 h at either -20 or -70 degrees C yielded C. fetus subsp. jejuni. Specimens dried on filter paper strips were negative for C. fetus subsp. jejuni within 1.5 h. Cary-Blair medium with decreased agar was the best of the six transport media tested, it enabled recovery of the organism from 100% (3 days) and 71% (7 days) of cecal samples held at 4 degrees C and 94% (3 days) and 85% (7 days) of cecal specimens held at 25 degrees C. In contrast, more than half of all cecal specimens held at 4 or 25 degrees C in Culturettes or buffered glycerol saline were negative by 3 days, and all were negative at 7 days. Results with the other three media studied (Campy-thio, thioglycolate medium, and alkaline peptone water) were intermediate. Overnight incubation of specimens in alkaline peptone water at 37 or 42 degrees C did not enhance recovery of C. fetus subsp. jejuni. Therefore, refrigeration without a transport medium is satisfactory for up to 3 days for recovery of C. fetus subsp. jejuni from specimens, however, we recommend the use of Cary-Blair medium with decreased agar for specimens that must be transported or stored for longer than 3 days and for rectal swabs, to prevent drying.

Animals↗