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J L Staneck

Publications and source records attributed to J L Staneck.

47 records · Page 3Linked to original sources

Staphylococcus aureus associated with toxic shock syndrome: phage typing and toxin capability testing.

Phage type 29 Staphylococcus aureus was identified singly or with type 52 in 64.1% of 248 coded isolates from patients with toxic shock syndrome. These phage types also have a high capability of producing pyrogenic exotoxin C and enterotoxin F. The origin and development of these toxigenic strains were explored by studying 25,220 isolates of S. aureus stored in a staphylococcal bank between 1960 and 1979. A small percentage of phage types 29, 52 were found in 1960, but their prevalence increased between 1961 and 1970, and continued at elevated levels through 1979. The toxigenic capabilities of these phage types were apparently acquired about 1971 and increased up to 1975. High levels of prevalence persisted during the following 4 years, and receded in 1980 and 1981. Other evidence during 1980 and 1981 indicates that these strains of S. aureus have become an important pathogen in surgical wounds, burns, and other infections.

Bacterial Toxins↗

Infection of bone by Mycobacterium fortuitum masquerading as Nocardia asteroides.

A case of traumatic osteomyelitis of the leg yielded on culture a branching partially acid-fast organism that failed to respond to therapy directed at Nocardia asteroides. Subsequent laboratory investigation revealed the organism to be Mycobacterium fortuitum. N. asteroides and M. fortuitum can demonstrate similar staining and morphologic patterns microscopically, as well as common colonial and cultural characteristics. Separation can be aided by careful examination of the branching pattern, and can be established by thin-layer chromatography of lipid extracts of the organism. Correct identification of these species in the laboratory is important because of some overlap in their clinical syndromes and because of differences in their susceptibilities to antibiotics.

Aged↗

Inhibition of Neisseria gonorrhoeae by sodium polyanetholesulfonate.

Sodium polyanetholesulfonate (SPS), in concentrations commonly used in blood culture media, inhibited the growth of a significant number of isolates of Neisseria gonorrhoeae in an agar dilution system. This SPS toxicity, shown to be bactericidal when examined in broth culture, could be reversed by hemoglobin and gelatin. Gelatin in 1% concentration allowed optimal growth of SPS-sensitive isolates in the presence of 0.025% SPS. Of 50 clinical isolates of N. gonorrheae tested under simulated blood cultures conditions with SPS, 16 isolates failed to grow on subculture at days 1, 3, and 10 after inoculation. Recovery was delayed with eight isolates as compared to controls. Early subcultures at 4, 8, and 12 h failed to recover SPS-sensitive isolates, whereas 1% gelatin, added even as late as 8 h after inoculation, reversed the SPS toxicity. The data reported suggest that SPS at concentrations routinely used in blood cultures can delay or prevent isolation of N. gonorrhoeae, but 1% gelatin can eliminate this adverse effect.

Benzenesulfonates↗

Pediatric Legionnaires' disease: diagnosis by direct immunofluorescent staining of sputum.

Legionnaires' disease occurred in a 3-year-old boy with Down's syndrome. His illness was characterized by bilateral pneumonia, high fever, and response to erythromycin. The diagnosis was made by demonstrating Legionella pneumophila, serogroup 1, in sputum with a direct fluorescent antibody stain. L pneumophila antigen was detected in urine by an enzyme-linked immunospecific assay. The diagnosis was confirmed by a more than fourfold rise in serum antibody titer. Although Legionnaires' disease appears to be uncommon in children, it should be included in the differential diagnosis of pneumonia in the immunocompromised child.

Antibodies, Bacterial↗

Neonatal necrotizing enterocolitis associated with penicillin-resistant, toxigenic Clostridium butyricum.

The cause of neonatal necrotizing enterocolitis (NEC) is unknown. An association between NEC and clostridial infection has been reported from several centers, but the organisms have not been extensively characterized. Clostridium butyricum was isolated from the peritoneal fluid and cerebrospinal fluid of a neonate with NEC. The organism was resistant to the penicillins, but sensitive to vancomycin. Toxin production was demonstrated. Although the role of clostridial toxins in the pathogenesis of NEC is unknown, clostridial toxins are well established as the causes of two other intestinal diseases (antibiotic-associated pseudomembranous colitis and pig-bel). Further investigation of the role of clostridia in the pathogenesis of NEC and of the use of oral, nonabsorbable antibiotics in the treatment of NEC is needed.

Bacterial Toxins↗

Antimicrobial susceptibilities of anaerobic bacteria: recent clinical isolates.

Minimal inhibitory concentrations of clindamycin, minocycline, metronidazole, penicillin, and carbenicillin were determined by agar dilution against 150 recent clinical isolates of anaerobic bacteria. Ninety-nine percent of Bacteroides fragilis and all B. melaninogenicus, Clostridium perfringens, and Fusobacterium were inhibited by clindamycin at 3.1 mug/ml. Only 58% of other clostridial species were inhibited by this concentration of clindamycin. Minocycline at 3.1 mug/ml inhibited 72% of C. perfringens, 81% of other Clostridium species, and 66, 75, and 100% of B. fragilis, B. melaninogenicus, and Fusobacterium, respectively. Metronidazole at 12.5 mug/ml inhibited all bacteria tested. B. fragilis was resistant to both penicillin and carbenicillin at 6.2 mug/ml. Concentrations of 25 mug/ml for penicillin and 100 mug/ml for carbenicillin were needed to inhibit more than 90% of B. fragilis. Organisms other than B. fragilis were moderately or extremely susceptible to the penicillins.

Anti-Bacterial Agents↗

Simplified approach to identification of aerobic actinomycetes by thin-layer chromatography.

A system has been developed for the identification of aerobic actinomycetes in the clinical laboratory based on analysis of whole cells for diaminopimelic acid and carbohydrates and on the ability of the organism to decompose casein, tyrosine, and xanthine media. The whole-cell analyses were performed by a simple thin-layer chromatographic procedure that is described. Eighteen reference cultures were correctly identified and, subsequently, 35 isolates from clinical material were grouped by using this system. The method is well suited for use in routine clinical laboratories.

Actinomycetales↗

Growth requirements of pathogenic Leptospira.

Nutritional requirements for growth at 30 C of Leptospira pomona and L. canicola have been determined. Both pathogenic serotypes initially required bovine serum albumin (BSA) for growth in a medium (SM-4) which permitted growth of the water isolate B-16. Requirement for BSA was eliminated by (i) removing much of the apparent toxicity of free fatty acids in Tween 80 on an anion exchange column, (ii) decreasing extended lag periods observed from small inocula by incorporation of pyruvate into the medium, (iii) the addition of acetate to permit full utilization of substrate fatty acids in Tween 80, and (iv) the addition of glycerol to decrease generation times. Physiologic significance of these findings is discussed, and the possibility is suggested that apparent toxicity of fatty acids for leptospires may result from their auto-oxidation products. The resulting protein-free medium (SM-5) permitted the growth of pathogens at 30 C to high cell yields in low inocula. Highly virulent and avirulent strains from the same clone of L. canicola Moulton were used to determine additional growth requirements associated with virulence. As incubation temperatures were increased from 30 C to those of mammalian hosts, virulent cells required biotin at 35 C and higher levels of K(+) and Mg(2+) at 37 C. Additional Fe(2+) eliminated the necessity for removing the toxicity of Tween 80 by anion exchange. Significance of these physiologic studies are discussed in relationship to virulence. The final protein-free medium (SM-6) grew highly virulent L. canicola from tissue to high yields from low inocula at 37 C with no loss in virulence over several transfers.

Acetates↗

Bioassay of teicoplanin in serum containing rifampin or a beta-lactam antibiotic.

The purpose of this study was to develop bioassays for the measurement of teicoplanin in serum containing rifampin or a beta-lactam antibiotic. Use of rifampin-resistant Bacillus subtilis as indicator organism or pretreatment of the serum sample with Bacillus cereus penicillinase Type I (nafcillin, ticarcillin, mezlocillin) or Type II (cefazolin, cefuroxime, ceftazidime, ceftriaxone) effectively eliminated assay interference. Validation bioassays performed on two separate days utilizing triplicate coded serum samples containing 0 to 200 micrograms teicoplanin in combination with 40 micrograms/ml rifampin or 200 to 500 micrograms/ml beta-lactam showed no significant differences (p greater than 0.05, two-way analysis of variance) in analyte recovery between assay days. Regression analysis of each teicoplanin/rifampin or teicoplanin/beta-lactam data set yielded slope values of 0.92 to 1.01, intercept values of -0.45 to 0.84 and correlation coefficients of 0.9925 to 0.9990. Thus, serum teicoplanin can be quantitated accurately, precisely, and reproducibly in patients receiving concomitant rifampin or beta-lactam chemotherapy.

Analysis of Variance↗

Impact of technological developments and organizational strategies on clinical laboratory cost reduction.

Health care reform efforts, largely under the aegis of managed health care initiatives, have prompted clinical laboratories to increase efficiency and reduce both expenditures and test turnaround times. The adoption of newer technologies is viewed as a mechanism of achieving the latter objectives, but direct and indirect costs and outcomes are often difficult to project. Issues explored in this article include the impact on a large university hospital-based clinical microbiology laboratory following the application of various technological approaches to organism recognition and susceptibility testing and the consolidation of certain testing services. Included are applications of an automated blood culture system; radiometric detection, identification, and susceptibility testing of mycobacteria; and the use of molecular probes to identify various microorganisms. Assessment was made through retrospective review of direct costs, estimates of average test report turnaround times, work flow changes, and real or perceived outcomes. Both the application of technology per se and consolidation of an independent virology service into the general microbiology laboratory enabled improvement in test report times and led to direct or indirect cost reduction. Managerial strategies to bring about organization changes throughout all clinical laboratories in response to a major hospital-wide cost reduction program are also presented together with financial outcomes achieved.

Bacterial Typing Techniques↗