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R C Bartlett

Publications and source records attributed to R C Bartlett.

At least 19 recordsLinked to original sources
PubMed1994

Evolving approaches to management of quality in clinical microbiology.

Quality management in clinical microbiology began in the 1960s. Both government and professional societies introduced programs for proficiency testing and laboratory inspection and accreditation. Many laboratory scientists and pathologists were independently active and creative in expanding efforts to monitor and improve practices. The initial emphasis was placed on intralaboratory process. Later, attention was shifted to physician ordering, specimen collection, reporting, and use of information. Quality management in the laboratory depends in large part on the monitoring of indicators that provide some evidence of how laboratory resources are being used and how the information benefits patient care. Continuous quality improvement should be introduced. This consists of a more thorough assessment of doing the right things versus the wrong things in terms of customer demand and satisfaction and studying the cumulative effect of error when responsibility is passed from one person to another. Prevention of error is accomplished more through effective training and continuing education than through surveillance. Also, this system will force more conscious attention to meeting the expectations of the many customers that must be satisfied by laboratory services, including patients, physicians, third-party payers, and managed-care organizations.

Clinical Competence↗
PubMed1994

Reagent strip screening for sediment abnormalities identified by automated microscopy in urine from patients suspected to have urinary tract disease.

We assessed the ability of reagent strip screening to predict the finding of blood cells and bacteria using an automated urinalysis workstation (The Yellow IRIS, International Remote Imaging Systems, Chatsworth, Calif) in 427 specimens submitted for urine culture. The sensitivities of leukocyte esterase, hemoglobin, and nitrite detection on reagent strips were 71.9%, 70.8%, and 56.7%, respectively, at 5 or more white blood cells per high-power field, at 3 or more red blood cells per high-power field and bacteria observed using the IRIS. Screening results for leukocyte esterase associated with negative results using the IRIS for white blood cells represented mostly false-positive screening test results based on chart review. Positive screening test results for hemoglobin associated with negative results obtained with the IRIS for red blood cells consisted of equal numbers of false-positive screening test results and IRIS test results based on chart review. A common screening algorithm using a combination of these three reagent strip variables exhibited a false-negative rate of 30.1%: review of medical records found clinical evidence of urinary tract infection in 14 patients and genitourinary or renal disease or hypertension in another 13 patients. Adding more variables to the algorithm increases the sensitivity and decreases the specificity. Both microscopic examination and reagent strip testing of urine are necessary for the detection of abnormalities associated with disease.

Algorithms↗
PubMed1992

The comparative activity of fleroxacin, three other quinolones and eight unrelated antimicrobial agents.

The in vitro activity of fleroxacin, a new trifluorinated quinolone was evaluated against 432 bacterial isolates. Fleroxacin was 1- to 2-fold less active than ciprofloxacin and at least as active as ofloxacin and lomefloxacin against most members of the family Enterobacteriaceae. The MICs of fleroxacin for 90% of strains tested (MIC90) were < or = 0.25 micrograms/ml against all isolates of Enterobacteriaceae except Citrobacter freundii (MIC90, 4 micrograms/ml) and Serratia marcescens (MIC90, 2 micrograms/ml). Fleroxacin was as active as ciprofloxacin, ofloxacin and lomefloxacin against Pseudomonas spp, (MIC90 for all quinolones tested were > 8 micrograms/ml). Acinetobacter and Haemophilus influenzae were very susceptible to fleroxacin; however fleroxacin was 1-fold less active than lomefloxacin against Acinetobacter and at least 1-fold less active than ciprofloxacin or ofloxacin against H. influenzae. Methicillin-susceptible and -resistant strains of Staphylococcus epidermidis and methicillin-susceptible strains of S. aureus were very susceptible to fleroxacin, with an MIC90 < or = 1 microgram/ml (range 0.5-1 microgram/ml). Methicillin-resistant S. aureus and Staphylococcus spp. other than aureus and epidermidis were not susceptible to fleroxacin (MIC90 > 8 micrograms/ml). In addition, fleroxacin as well as ciprofloxacin, ofloxacin and lomefloxacin were inactive against Enterococcus spp. (MIC90 > 8 micrograms/ml). Streptococcus pneumoniae and S. pyogenes were resistant to both fleroxacin and lomefloxacin but were very susceptible to ciprofloxacin and ofloxacin. These results suggest that fleroxacin represents a valid therapeutic option in the treatment of infections caused by most Enterobacteriaceae and some species of staphylococcus.

Anti-Bacterial Agents↗
PubMed1991

Laboratory reports issued on or after discharge date.

The authors of this article discuss the problem of ensuring that physicians are informed of bacteriology test results in a timely manner, a study they undertook, and the steps taken to solve the problem.

Clinical Laboratory Information Systems↗
PubMed1990

Trends in quality management.

The history of quality control in the clinical laboratory dates at least to 1950. The last 20 years have seen an increasing interposition of regulators that has focused much quality management activity on inspection and fault finding. Recently, the emphasis has turned from monitoring the process within the laboratory to application of indicators as measures of outcome. Most recently, the industrial example of continuous quality improvement offers an opportunity for reduction of costs and improvement of quality in an atmosphere of increasing competition and cost containment. Such an approach offers the opportunity to provide cost-effective, efficient health care for Americans as an alternative to government management.

Cost-Benefit Analysis↗
PubMed1985

Differentiation of Pseudomonas aeruginosa and Enterobacteriaceae in direct smears based on measurements by scanning electron microscopy.

We believe that experienced observers can often distinguish between Enterobacteriaceae and Pseudomonas aeruginosa, by differences in dimensions in Gram-stained direct smears. Many microbiologists question whether this should be attempted because of overlap in dimensions. We have found that culture results confirm our observations about 80% of the time and that such reporting is helpful in diagnosis and treatment. We decided to try to verify the differences in dimensions objectively. Because of the limitations of making measurements by light microscopy, exudate from clinical specimens and from experimental mouse infections were examined by scanning electron microscopy. Discriminant function analysis was applied to the dimensions of length and width, and this showed that 83% of the organisms in both groups could be correctly classified on the basis of the dimensions. This supports our premise that experienced observers should be able to differentiate between these organisms in Gram-stained direct smears, using light microscopy with sufficient confidence to provide clinically useful information.

Animals↗
PubMed1985

Antimicrobial synergy testing based on antibiotic levels, minimal bactericidal concentration, and serum bactericidal activity.

The ratio between the concentrations of different antimicrobial agents varies widely during therapy and often bears no resemblance to the ratios assessed by in vitro methods to evaluate the effectiveness of multiple antimicrobial therapy. The authors examined an alternative method using patient serum that reflects the actual antibiotic levels achieved in the patient. Previous investigators have shown that the ratio of the concentration of free drug (drug-f) to the minimal bactericidal concentration (MBC) in broth approximates the serum bactericidal titer (SBT) when pooled normal human serum is used as the diluent. Theoretically, when two antimicrobial agents are administered, the SBT should be equivalent to (drug-f A/MBC drug A) + (drug-f B/MBC drug B). SBT and drug level determinations were performed on peak and trough serum specimens from ten patients with endocarditis or osteomyelitis who were receiving multiple antimicrobial therapy. The serum dilution synergy method predicted additive interactions twice as often as the checkerboard and kill curve, and predicted synergy less frequently than the kill curve. The checkerboard predicted antagonism four times more often than the other methods and provided equivocal results in four of ten cases. The suggested method may offer an alternative procedure to assess antimicrobial interactions, which is based on antibiotic levels actually achieved in vivo instead of the arbitrary concentrations often used in in vitro tests.

Adult↗
PubMed1985

Cost containment in microbiology.

Prospective reimbursement will impose an additional challenge on clinical microbiologists. In order to avoid an inevitable decrease in quality and increasing delay in providing results of examination of specimens, efforts must be undertaken to restrict the submission of specimens and the extent of work that is performed to that which is cost effective for patient care. This will require education and the introduction by the laboratory of controls on ordering and specimen submission. Laboratory personnel must also establish criteria to limit the extent of specimen processing to the production of information that can be expected to be clinically useful. This will involve a close interaction with infectious disease services and clinical departments. Introduction of new screening tests, rapid antigen detection procedures, computers, and automation may provide some increase in productivity but cannot be expected to solve the entire problem. Currently, most attention to controlling hospital cost is being given to the length of patient stay, and little progress has been made in establishing more effective communication between laboratory staffs, house staffs, medical staffs, and hospital administration in monitoring and controlling misuse of laboratory resources.

Clinical Laboratory Techniques↗
PubMed1984

Clinical significance of mixed bacterial cultures of urine.

The frequency with which isolation of more than one bacterial species from urine signifies treatable mixed infection versus contamination or colonization is not known. The authors studied 247 patients yielding mixed urine cultures. Specimens were collected by clean catch (CC) from 88 and from closed drainage systems (CDS) from 159. A second specimen was collected within 48 hours, and the results of the two cultures were compared. The percentages in which the initial mixed culture was found to represent probable, possible, and improbable treatable mixed infection were as follows: for CC specimens, 11%, 20%, and 67%, and for CDS specimens, 3%, 21%, and 77%. The authors have found that empiric antibiotic therapy and reporting of mixed cultures based on culture morphology without complete identification or antibiotic susceptibilities (except for certain colony types suggesting potentially multi-drug resistant strains) with request for resubmission represents a cost-effective solution to the mixed culture problem in the diagnosis and treatment of urinary tract infection.

Anti-Bacterial Agents↗
PubMed1984

Detection of bacteriuria by leukocyte esterase, nitrite, and the automicrobic system.

The predictive value for detection of significant bacteriuria was determined for use of the Chemstrip leukocyte esterase-nitrite dipstick (LN) and the Vitek Automicrobic System (AMS) using a conventional culture method (CM) as the reference procedure. The predictive values for positive and negative tests for detection of greater than or equal to 10(5) bacteria/mL for LN testing alone (2,782 specimens), AMS testing alone (729 specimens), and AMS testing of only LN positive specimens (253 specimens) were 29% and 97%, 67% and 99.5%, and 74.7% and 99.4%. The low predictive values for positive AMS tests were the result of discrepancies in enumeration in which counts of 10(4)/mL by CM often were classified as 10(5)/mL by AMS. Screening of specimens by LN reduces the cost of subsequent processing of LN positive specimens. Processing of LN positives by CM yielded the lowest total cost. Processing of LN positives by AMS resulted in the lowest labor cost.

Autoanalysis↗
PubMed1984

Usefulness of microscopic examination in urinalysis.

The authors evaluated 500 patients who yielded urine specimens containing red and white blood cells but that gave negative reagent test strip reactions to determine the medical usefulness of the microscopic examination in such cases. Half of the patients had a history of, or current signs and symptoms of genitourinary or renal disease (GURD), or had indwelling catheters, hypertension, or diabetes. The other half did not display these conditions. Red blood cells occurred rarely, and no red blood cell associated GURD was detected in these patients. Five had lower urinary tract infection. Seventy-two underwent further workup, but no GURD was found. Physicians did not comment or take action on the report in other patients. The authors found the test for leukocyte esterase and nitrite (LN) to have a predictive value for a negative result of 97% for exclusion of bacteruria. Based on these observations, the authors established in 1982 a policy that microscopic examination would be performed only on specimens negative by reagent test strip (including LN) if a "diagnostic urinalysis" (DU) was ordered. The authors recommended that DU be requested only for patients suspected of GURD. This has eliminated microscopic examinations on 25% of specimens and reduced costs.

Bacteriuria↗