Biomedical subjects

F A Meier

Publications and source records attributed to F A Meier.

11 recordsLinked to original sources

PubMed1992

Rapid identification of motile Aeromonas.

The clinical relevance and taxonomy of motile Aeromonas species are areas of current controversy. Strains of motile Aeromonas isolates (n = 60) from various sources were identified to species level using the following tests (all incubated at 30 degrees and 37 degrees C): esculin hydrolysis; formation of gas from glucose; production of acetoin; production of acid from mannitol and arabinose; decarboxylation of lysine and ornithine, dihydrolation of arginine; and pyrazinamide hydrolysis in a semisolid medium. The tests' results were similar at incubation temperatures of 30 degrees and 37 degrees C. Of the strains, 59 (98%) of 60 were identified to species level by the full battery of tests: 25 as A. hydrophila, 18 as A. caviae, 14 as A. sobria, one as A. veronii, and one as A. schubertii. (The only A. veronii and A. schubertii isolates identified were ATCC strains). All (25 of 25) strains of A. hydrophila and 17 (94%) of 18 of A. caviae hydrolyzed pyrazinamide in less than 24 hr, whereas all strains of A. sobria showed no pyrazinamidase activity. Absence of pyrazinamidase was, thus, a convenient phenotypic marker for A. sobria. Four additional tests (esculin hydrolysis, acetoin production, lysine decarboxylation, and gas production from glucose) identified within 24 hr all examples of the three common species of Aeromonas. Recently proposed species did not contribute to our ability to discriminate among stool, other clinical, and environmental isolates of Aeromonas spp.

Aeromonas↗

PubMed1990

Derivation and validation of a clinical diagnostic model for chlamydial cervical infection in university women.

We developed and prospectively tested a logistic regression model for chlamydial cervical infection. Study subjects included 2271 women receiving gynecologic care in our student health clinic. Clinical data were collected in a standardized fashion. We identified cell culture--isolated Chlamydia trachomatis from 133 (9%) of 1458 subjects in the derivation set and 73 (10%) of 729 subjects in the validation set. Model variables included a new sexual partner within 2 months or more than one sexual partner within 6 months; cervical ectopy; cervical friability; at least 20 polymorphonuclear leukocytes per high-power field in cervical secretions; white blood cells in vaginal secretions; and use of an antibiotic active against C trachomatis within a month. This model can distinguish women with low, medium, and high risks of chlamydial infection (on derivation set: receiver operating characteristic curve area, 0.710; SE, 0.026; on validation set: area, 0.698; SE, 0.035) using simple clinical information obtained in the office.

Adolescent↗

PubMed1990

Cerebral botryomycosis: case study.

After oral surgery, a 32-year-old man developed a brain abscess. Actinomycosis was suspected due to history, clinical findings, response to penicillin therapy, and demonstration of "sulfur granules" in the surgical specimen, but anaerobic cultures were negative for Actinomyces. Aerobic cultures yielded Streptococcus sanguis and Pseudomonas cepacia. Coccoid organisms demonstrated histologically reacted positively with periodic acid-Schiff, Gomori's methenamine silver, and Brown and Brenn stains, were Ziehl-Neelsen-negative, and did not include branching filaments. Fluorescent antibody assay for Actinomyces israelii was also negative. Electron microscopy revealed cell wall morphology and pattern of cell division characteristic of gram-positive cocci. These findings led to a final diagnosis of botromycosis due to S. sanguis. This third report of cerebral botryomycosis emphasizes the differential diagnosis with actinomycosis, the association with intermittently treated jaw disease, and identification of the causative agent by histologic, immunologic, and electron microscopic methods.

Actinomycosis↗

PubMed1990

Two confirmatory tests for identification of Neisseria gonorrhoeae from primary culture.

We compared a fluorescent monoclonal antibody and a DNA probe for identification of Neisseria gonorrhoeae (GC) from primary genital cultures of presumptive GC and selected bacterial isolates other than GC. The monoclonal antibody was sensitive (94%) and specific (100%) enough to identify GC in selective primary genital culture. The DNA probe was sensitive (95%) but not adequately specific (65%) to function as a confirmatory test.

DNA Probes↗

PubMed1990

Effects of a rapid antigen test for group A streptococcal pharyngitis on physician prescribing and antibiotic costs.

Decision analysis and opinion survey suggest that introduction of rapid antigen detection tests should decrease the number of patients with negative test results for group A streptococcal pharyngitis treated by antibiotics. We reviewed all cases in which a test for group A streptococcal pharyngitis was performed during the last 7 months of culture diagnosis and the first 7 months of antigen test diagnosis at an inner city community health center, recording culture or antigen test results, whether antibiotics were prescribed, and patient status (as regular health center patients or patients referred to the center). Positive rates for culture and antigen-test periods were similar (10% and 12%), but 53% of patients with negative culture were treated, where only 32% of patients with negative antigen-test results received prescriptions. Significant reductions in the treatment of patients with negative test results were found in both patient-status subpopulations: health center patients, 43% to 29%; referred patients, 91% to 52%. Among health center patients reductions were consistent for both adult (30% to 21%) and child and adolescent (55% to 45%) age groups. For all patients with negative test results, direct costs of diagnostic reagents and antibiotic prescriptions fell from $3.58 per patient with culture to $3.45 with antigen testing; the $0.13 savings per patient was due to less treatment of referred patients. Thus, rapid antigen testing led to (1) significantly fewer patients with negative test results receiving antibiotic prescriptions; and, (2) savings in antibiotic costs offsetting reagent cost of antigen detection diagnosis.

Adolescent↗

PubMed1990

Clinical and microbiological evidence for endemic pharyngitis among adults due to group C streptococci.

Group C beta-hemolytic streptococci cause rare epidemic outbreaks of pharyngitis, but their role in sporadic endemic pharyngitis has been uncertain. We addressed the question of whether non-group A beta-hemolytic streptococci are associated with endemic pharyngitis in two ways. First, we compared rates of isolation from throat swabs of group A, B, C, and G and ungrouped beta-hemolytic streptococci ("culture negative") in adult patients vs those rates in controls. Second, we collected in standardized form clinical indexes of patients with pharyngitis: signs and symptoms graded for severity, the examining physician's subjective estimate of the probability of streptococcal pharyngitis, a logistic regression score predicting streptococcal pharyngitis, and whether antibiotic therapy was prescribed. After collecting data and cultures on 1425 patients with sore throats and cultures on 284 controls, we found the following: group C streptococci were isolated significantly more frequently in patients with sore throats than in controls (6% vs 1.4%); four clinical signs and two symptoms distinguished group C-associated pharyngitis as more severe than culture-negative pharyngitis; and six clinical signs and one symptom distinguished group C-associated pharyngitis as less severe than group A pharyngitis. Physicians' subjective estimates, logistic regression scores, and antibiotic treatment all characterized group C-associated pharyngitis as more severe than culture-negative sore throats but less severe than group A pharyngitis. From these data we present the first definitive evidence that group C streptococci are associated with endemic pharyngitis, show that clinical presentation distinguishes a group of patients with group C-associated pharyngitis from populations with culture-negative sore throats and from those with group A pharyngitis. Physicians' response to that presentation merits consideration in the context of rapid group-specific diagnosis of streptococcal pharyngitis by group A antigen tests.

Adult↗

PubMed1987

Nosocomial outbreak of Legionnaires' disease: molecular epidemiology and disease control measures.

Molecular laboratory techniques were used to study the epidemiology of an outbreak of nosocomial Legionnaires' disease. All patient isolates were Legionella pneumophila serogroup 1 and showed identical plasmid profiles and reactions with serogroup-specific monoclonal antibodies. L pneumophila was also cultured from four of five cooling tower water samples; however, the isolate from only one tower was serogroup 1 of the same subtype as patient isolates. Since the cases were temporally clustered and epidemiologically associated with exposure to cooling tower aerosols, the single cooling tower implicated by molecular analysis was the most likely source of the outbreak. Chlorination of cooling tower ponds has eradicated the epidemic strain. Since potable water also harbored the infecting organism and was the probable source for cooling tower contamination, decontamination of the hospital water system was also undertaken. Superchlorination of hot water holding tanks to 17 ppm on a weekly basis has effectively eradicated L pneumophila from the potable water system and appears to be a reasonable, simple, and relatively inexpensive alternative to previously described methods of control.

Cross Infection↗

PubMed1986

Effect of medium and cultivation conditions on comparisons between latex agglutination and culture detection of group A streptococci.

In the laboratory diagnosis of pharyngitis, results from latex agglutination tests (LAT) performed directly on throat swabs are often compared with the isolation of group A beta-hemolytic streptococci (GABHS) from simultaneously obtained swabs cultivated on a variety of media under different atmospheric conditions. In this study, results of an LAT, Directigen, were compared with those of two different media: sheep blood agar (SBA) and group A selective strep agar (ssA). Specimens inoculated on SBA were incubated in three different atmospheres: air, 3 to 5% CO2, and anaerobically. Those inoculated on ssA were incubated in 3 to 5% CO2 only. Isolation of GABHS was confirmed by coagglutination. The standard for true positivity was the isolation of GABHS from at least one of the simultaneous cultures. Comparisons were made with samples from 693 adult patients. GABHS was isolated on at least one of the three cultures in 143 patients, demonstrating an isolation rate of 20.6%. LAT exhibited a sensitivity of 95.1%. SBA incubated in air, in CO2, or anaerobically had sensitivities of 86.2, 85.9, and 93.7%, respectively. The ssA detected 99.3% of the positive specimens. Single SBA culture proved to be inferior to LAT and therefore was a poor standard for measuring LAT performance. Single ssA cultures demonstrated the greatest sensitivity in GABHS detection and therefore could serve as a standard for measuring LAT performance.

Aerobiosis↗

PubMed1979

Serum-ferritin.

Explore the source record for details and available documents.

Anemia, Hypochromic↗

PubMedDate not supplied

Evaluation of two ELISA's for detecting Chlamydia trachomatis from endocervical swabs.

Two enzyme immunoassays (EIAs) detecting Chlamydia trachomatis from endocervical swabs, Syva MicroTrak (MT) and Abbott Chlamydiazyme (CZ), were compared with a tissue culture (TC) standard. Initially, 8% (100 of 1250) of specimens were TC positive, yielding sensitivities of 94% (94 of 100) for MT and 79% (79 of 100) for CZ with identical 98% specificities (1129 of 1150 for MT and 1130 of 1150 for CZ). Discrepant specimens were retested by both EIAs and assayed for elementary bodies (EBs) by a fluorescent antibody test. After discrepancy analysis, 9.5% (118) of 1240 patients were either TC or EB positive, yielding sensitivities of 94.1% for MT (111 of 118) and 79.7% for CZ (94 of 118) with identical specificities of 100% (1122 of 1122). These results indicate that the MT is significantly more sensitive (p less than 0.05, McNemar test) than CZ in detecting C. trachomatis from endocervical swabs.

Adolescent↗

PubMedDate not supplied

Meningitis due to Neisseria mucosa: case report and review.

Neisseria mucosa is a species of gram-negative cocci that has a characteristic mucoid, adherent colonial morphology and includes pigmented and nonpigmented morphotypes. The ability of N. mucosa to reduce nitrates distinguishes it from other Neisseria species. N. mucosa is part of the normal human nasopharyngeal flora and infrequently causes human infections, including meningitis. We report a unique case of a patient with a cerebrospinal fluid shunt infection due to N. mucosa and review five other reports of cases of meningitis caused by this organism. Seven additional previously reported cases of presumed N. mucosa meningitis have been excluded from this review on the basis of the current criteria for identification of the organism. In the reports of established cases, female infants and children who often had predisposing conditions predominate. Although the outcome for such patients has been favorable, no clinical or laboratory findings are helpful in distinguishing meningitis due to N. mucosa from that due to other bacteria.

Adult↗