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V J Gill

Publications and source records attributed to V J Gill.

71 records · Page 4Linked to original sources

Use of lysis-centrifugation (isolator) and radiometric (BACTEC) blood culture systems for the detection of mycobacteremia.

Patients with acquired immune deficiency syndrome may develop infection with mycobacteria, particularly Mycobacterium avium-M. intracellulare (MAI). These infections can frequently be associated with demonstrable mycobacteremia with the organism. In this study, we compared the sensitivity of a radiometric (BACTEC system; Johnston Laboratories, Inc., Towson, Md.) liquid medium culture system with that of conventional solid mycobacterial culture media for cultures of blood from these patients. Both systems were inoculated with blood concentrate prepared by lysis-centrifugation (Isolator; Du Pont Co., Wilmington, Del.). Of 46 acquired immune deficiency syndrome patients whose blood was cultured, 28% had cultures positive for MAI. Patients had from less than 1 to more than 100 MAI colonies per ml of blood. Lowenstein-Jensen and Middlebrook 7H11 agars were comparable in recovery of MAI. BACTEC 12A vials containing double the standard volume of medium (4 ml) were more sensitive and were positive slightly earlier than vials containing the standard volume (2 ml). Conventional media detected 98% of positive cultures; BACTEC vials containing double volumes of medium detected 94% of positive cultures, whereas single-volume vials detected 77%. BACTEC vials were positive approximately 5 to 6 days sooner than slants or plates containing conventional media. For a few cultures, the use of unconcentrated blood was compared with the use of Isolator-concentrated blood by using each of these as inocula for BACTEC vials. Results for these cultures suggested that, although the use of Isolator-concentrated blood resulted in greater sensitivity than the use of unconcentrated blood would, the use of unconcentrated blood would still result in the detection of at least 78% of positive cultures.

Acquired Immunodeficiency Syndrome↗

Advantages of a modified toluidine blue O stain and bronchoalveolar lavage for the diagnosis of Pneumocystis carinii pneumonia.

A modified toluidine blue O staining technique for Pneumocystis carinii is described. An easily prepared sulfation reagent made with sulfuric and acetic acids was used. The stain can be employed for bronchoalveolar lavages and lung tissue touch preparations. Most background material was removed by the sulfation reagent, slides were generally easy to read, and time from receipt of a specimen to reporting of results was approximately 1 h. P. carinii cysts were more easily visualized with this stain than in slides stained with modified methylene blue, Gram, Gram-Weigert, and standard toluidine blue O procedures. The importance of certain procedural aspects of subsegmental bronchoalveolar lavage, by which most of the specimens were obtained, is also emphasized.

Humans↗

Cryptococcosis in the acquired immunodeficiency syndrome.

The clinical course and response to therapy of 27 patients with cryptococcosis and the acquired immunodeficiency syndrome were reviewed. Cryptococcosis was the initial manifestation of the syndrome in 7 patients, and the initial opportunistic infection in an additional 7. Meningitis was the commonest clinical feature (18 patients). Blood cultures and serum cryptococcal antigen were frequently positive. In patients with meningitis, leukocyte count, protein level, and glucose level in cerebrospinal fluid were frequently normal; cerebrospinal fluid India ink test (82%), culture (100%), and cryptococcal antigen (100%) were usually positive. Only 10 of 24 patients had no evidence of clinical activity of cryptococcal infection after completion of therapy; 6 of these 10 had relapses shown by clinical findings or at autopsy. Standard courses of amphotericin B alone or combined with flucytosine were ineffective. Cryptococcosis in patients with the syndrome is a debilitating disease that does not respond to conventional therapy; earlier diagnosis or long-term suppressive therapy may improve the prognosis.

Acquired Immunodeficiency Syndrome↗

Comparison of lysis-centrifugation with lysis-filtration and a conventional unvented bottle for blood cultures.

Evaluation of a commercially available lysis-centrifugation blood culture system (Isolator, DuPont Co., Wilmington, Del.) and a lysis-filtration blood culture system for 3,111 cultures showed that both methods had comparable recoveries (73 and 68%, respectively) of significant aerobic and facultatively anaerobic isolates. The unvented conventional blood culture bottle had a recovery rate of 59%. Although the lysis-centrifugation and lysis-filtration systems had comparable recoveries of pathogens, the lysis-centrifugation system had the advantage of having colonies immediately available for further testing. The contamination rate with the lysis-centrifugation system was 3%, compared with 6% with the lysis-filtration system and 0.4% with brain heart infusion.

Bacteria↗

Species identification and antibiotic susceptibilities of coagulase-negative staphylococci isolated from clinical specimens.

Identification of potentially significant coagulase-negative staphylococci isolated from clinical specimens was performed along with antibiotic susceptibility determinations, S. epidermidis accounted for 75% of these isolates, with S. haemolyticus and S. hominis being the second and third most frequently encountered species, respectively. Although there were many instances of single blood culture isolations of questionable significance, all three species were also found in multiple blood cultures from individual patients, indicating the ability to cause significant bacteremia. The most common source for most species was blood, except for S. saprophyticus and S. simulans, which were found more frequently in urine. Of urinary tract isolates, however, S. epidermidis was more common than S. saprophyticus. Antibiotic susceptibility profiles demonstrated that S. haemolyticus and S. epidermidis were frequently multiply antibiotic resistant. S. haemolyticus had a higher percentage of isolates that were oxacillin, cephalothin, aminoglycoside, erythromycin, and clindamycin resistant than did S. epidermidis. We found that species identification could be of benefit for both epidemiological as well as patient care purposes, and that this additional information is readily available, using convenient and rapid new methods.

Anti-Bacterial Agents↗

Antibiotic-resistant group JK bacteria in hospitals.

The organisms designated as Center for Disease Control group JK are gram-positive rods that have previously been described as causing serious infection in compromised hosts. Four years of hospital experience with this group of organisms in Clinical Center patients was reviewed. Studies were also undertaken on specific wards to determine frequency of occurrence and distribution patterns. Inguinal cultures taken on two wards showed that 30 to 35% of patients were colonized with group JK and that newly admitted patients may already be colonized at the time of admission. Colonization was shown to persist for weeks and sometimes months. Isolates obtained throughout the hospital were predominantly from cancer patients, particularly in wounds, abscesses, and drainage sites. Most blood isolates were from granulocytopenic patients with hematological malignancies.

Anti-Bacterial Agents↗

Lack of clinical relevance in routine terminal subculturing of blood cultures.

The usefulness of performing final blind subcultures of previously negative blood cultures was evaluated over a 21-month period. From over 14,000 blood culture bottles blindly subcultured after 7 days of incubation, only 12 potentially significant organisms were found. The finding of these 12 organisms did not influence patient care since in 11 instances the same organism had already been reported from prior positive bottles and in 1 instance the patient had already died. These results suggest that blind 7-day subcultures are of minimal value. Other factors that need to be considered before eliminating the final subculture are presented.

Bacteria↗

Serratia ficaria isolated from a human clinical specimen.

The first isolation of Serratia ficaria from a human source is reported. Investigation into the eating habits of the patient revealed the probable source as figs, which are one of the natural reservoirs of this organism. How this and other normally saprophytic Serratia species can be distinguished from Serratia marcescens is reviewed.

Female↗

Correlation of penicillin minimum inhibitory concentrations and penicillin zone edge appearance with staphylococcal beta-lactamase production.

Production of staphylococcal beta-lactamase was shown to be correlated with penicillin G minimum inhibitory concentrations (MICs) of greater than 0.05 microgram/ml for 97% of the Staphylococcus aureus and 99% of the Staphylococcus epidermidis strains tested. However, it is important to note that of the isolates for which MICs were equal to or less than 0.05 micro/ml, a significant percentage (16% of S. aureus and 5% of S. epidermidis) were beta-lactamase producers. Thus, lack of beta-lactamase production, which implies susceptibility to penicillin, cannot be presumed solely on the basis of low MICs. Beta-lactamase production can be easily predicted from disk diffusion susceptibility tests by observing the appearance of the penicillin inhibition zone edge. A sharply demarcated edge was correlated with beta-lactamase production for 100% of the S. aureus and 93% of the S. epidermidis strains tested. The presence of this type of zone edge when a penicillin zone measures in the intermediate or susceptible range indicates that the isolate should be checked for beta-lactamase production.

Microbial Sensitivity Tests↗

Microbiology subsystem of a total, dedicated laboratory computer system.

The computer system used by the Microbiology Service of the Clinical Pathology Department, Clinical Center, National Institutes of Health is discussed. This microbiology subsystem is a part of a dedicated on-line laboratory computer system used by the entire department. The laboratory computer is connected on-line to a hospital computer which provides patient admission, transfer, and discharge data. Mark sense worksheets and cathode ray tube terminals are used for result entry and correction. Cumulative patient reports are printed. Results for both active and completed accessions can be easily retrieved on cathode ray terminals in the laboratory. All laboratory data are archived on magnetic tape from which a research data base and microfiched laboratory records are generated. The manner in which the system is integrated in the routine operation of the microbiology laboratory is emphasized. In addition, some of the costs, benefits, liabilities, and pitfalls associated with the introduction of the computer in the laboratory are reviewed. Finally, we have presented our concept of some of the future enhancements to our present system and some of the directions in which any future microbiology system might develop.

Computers↗

Rapid entry port for an anaerobic glove box.

A rapid entry mechanism for an anaerobic glove box is described. The entry port is practical for entry or removal of one or two items and requires only seconds to operate. No deleterious effect on isolation or growth of anaerobes has been encountered since installation of the rapid entry port 3.5 years ago. Details for its construction are given.

Anaerobiosis↗

Nitroblue tetrazolium and Limulus assays for bacteremia after dental extraction: effect of topical antiseptics.

Bacteremia that occurs after dental extraction is common. This study assessed the effect of topical antisepsis on the incidence and magnitude of post-extraction bacteremia. On hundred patients scheduled for elective tooth extraction were randomized among four groups: contr-l, mouthrinsing with sodium-p-toluene sulfonchloramide (chloramine-T), toothbrushing with chloramine-T, and irrigation with Lugol's solution. The results showed that 84% of the control group and 59% of the treatment groups had positive blood cultures (290 organisms isolated) after dental extraction. The duration and magnitude of these bacteremias were diminutive as documented by the six serial blood cultures taken for each patient, colony counts per milliliter of blood, and nitroblue tetrazolium and Limulus assays. Brushing the teeth or rinsing the mouth with chloramine-T before dental extraction significantly reduced the incidence of bacteremia (P less than .025) and the number of different organisms recovered from each patient (P less than .05). Thus, topical treatment with chloramine-T is a simple and effective means of reducing the incidence of postextraction bacteremia.

Adolescent↗

Leptotrichia buccalis bacteremia in patients with cancer: report of four cases and review.

Leptotrichia buccalis, an anaerobic gram-negative rod, is part of the normal oral flora and has rarely been isolated from clinical material. We describe four patients with neutropenia and progressive malignancy who had symptomatic L. buccalis bacteremia, and we review an additional four cases from the literature. The mean age of the patients was 31 years (range, 7-73 years), with an equal number of males and females. The number of positive blood cultures in each case ranged from one to four (mean, two); these cultures became positive after 48-120 hours (median, 54 hours). All tested isolates were sensitive to the beta-lactam agents, clindamycin, tetracycline, and metronidazole; five of seven were sensitive to chloramphenicol; and not one was sensitive to the aminoglycosides, vancomycin, ciprofloxacin, or erythromycin. Seven patients had one or more possible portals of entry for bacteremia, including mucositis (four patients), mucositis plus esophageal lesions (two), and possible mucositis plus diverticulitis (one). L. buccalis should be considered a potential pathogen in neutropenic patients, especially when breaks in the mucosal breaks in the mucosal barriers are present.

Adolescent↗

Use of ciprofloxacin for successful eradication of bacteremia due to Campylobacter cinaedi in a human immunodeficiency virus-infected person.

A 36-year-old homosexual man who was infected with human immunodeficiency virus presented with a 2-month history of fever and intermittent diarrhea. Stool cultures were negative for bacterial pathogens, ova, parasites, and acid-fast organisms. An initial blood culture became positive after 5 days for a curved, gram-negative rod that was identified later as Campylobacter cinaedi. The patient received a series of antibiotic regimens, including a 2-week course of erythromycin followed by a 2-week course of tetracycline, but follow-up blood cultures continued to yield C. cinaedi. The patient was then treated with a 2-week course of oral ciprofloxacin; he remained asymptomatic 11 weeks later, at which time a blood culture was negative for C. cinaedi. To the best of our knowledge, this is the first documented case of symptomatic bacteremia due to C. cinaedi that was successfully treated with ciprofloxacin.

Adult↗