Passive transfer of hepatitis antibodies during intravenous administration of immune globulin.

We studied the effect of intravenous immune globulin (IVIG) infusion on the levels of hepatitis B and C antibodies in 10 premature babies. All four tested lots of a commercially purchased IVIG preparation were found to contain substantial amounts of hepatitis B core and hepatitis C antibodies. Our results show that passive transfer of hepatitis B and C virus antibodies occurred after IVIG infusion, and that the levels were dependent on the quantity of IVIG given. When assessing neonates for hepatitis, the factor of receipt of blood products, including IVIG, needs to be considered to interpret laboratory results.

Evaluation of the new DrySlide beta-lactamase test.

Four hundred thirteen recent clinical isolates of Staphylococcus, Haemophilus, Moraxella, and Neisseria species were tested for beta-lactamase production using the Difco DrySlide beta-lactamase test. These results were compared with those of the BBL Cefinase reagent. Of the 413 isolates tested, 258 (62.5%) were beta-lactamase positive. There was 99.8% agreement between the two test methods; only one isolate of Staphylococcus aureus was DrySlide-negative and Cefinase-positive. The DrySlide beta-lactamase reagent is an accurate and convenient format for the evaluation of beta-lactamase activity in the clinical laboratory.

Detection of bacteremia by Difco ESP blood culture system.

In a multicenter study, the Difco ESP blood culture system (Difco Laboratories, Detroit, Mich.) was compared with the BACTEC NR660 system (Becton Dickinson Diagnostic Instrument Systems, Sparks, Md.). The ESP system monitors each blood culture bottle every 12 to 24 min to detect changes in oxygen consumption and gas production by microbes. Equal volumes of blood were inoculated into aerobic ESP-80A and BACTEC 6A, 16A, or PEDS Plus broths and anaerobic ESP-80N and BACTEC 7A or 17A broths and were incubated for up to 7 days. ESP bottles contain supplemented tryptic soy broth without antimicrobial agent-adsorbing resins. From 7,532 aerobic compliant sets, the ESP system detected 356 clinically significant positive cultures and the BACTEC NR660 system detected 329. From 6,007 anaerobic cultures, the ESP system detected 234 clinically significant positive cultures and the BACTEC NR660 system detected 198. In aerobic broths, 292 organisms were isolated from both systems and 78 organisms were isolated from the ESP system alone, whereas 54 organisms were isolated from the BACTEC NR660 system alone (P < 0.05). Among individual organisms, pneumococci were isolated significantly more often in ESP aerobic broths. In anaerobic broths, 180 organisms were isolated from both systems and 68 organisms were isolated from the ESP system alone, whereas 35 organisms were isolated from the BACTEC NR660 system alone (P < 0.05). Aerobic gram-positive organisms as a group and Candida spp. were isolated significantly more often in ESP anaerobic broths. Both systems detected 207 clinically significant bacteremic episodes and the ESP system alone detected 63, whereas the BACTEC NR660 system alone detected 32 (P < 0.05). Significantly more episodes of bacteremia caused by Staphylococcus epidermidis and anaerobes were detected by the ESP system. The differences in the numbers of organisms detected >6h earlier in ESP broths compared with BACTNEC NR660 broths were significant, as were earlier times to detection. Although the total number of organisms detected was not significantly different, the ESP system alone detected more organisms in a shorter time than did the BACTEC NR660 system alone. The continuous monitoring capability of the ESP system makes it an attractive alternative to the BACTEC NR660 system.

Antimicrobial activity of new antibiotics against bacterial isolates from a community hospital.

In this study, the antimicrobial activity of several new antibiotics was evaluated using microdilution antimicrobial susceptibility testing against 220 clinically significant isolates obtained from a community hospital. The following antibiotics were studied: loracarbef, cefixime, cefpirome, desacetylcefotaxime, cefpodoxime, cefmetazole, cefepime, cefprozil and fleroxacin. The synergy of two particular drug combinations was evaluated using cefpirome/desacetylcefotaxime and cefpodoxime/desacetylcefotaxime. Cefpirome was clearly the most active antibiotic: 88% of the isolates tested were found to be susceptible. Specifically, this included 89% of enterococci, 84% of Pseudomonas aeruginosa, and 33% of Pseudomonas cepacia. All of the antibiotics tested demonstrated excellent activity against isolates of Escherichia coli and Klebsiella, Proteus and Salmonella species. For the other antimicrobials, 57, 50, 64, 65, 76, 74, and 64% of the isolates were sensitive to loracarbef, cefixime, cefmetazole, cefprozil, fleroxacin, desacetylcefotaxime, and cefpodoxime, respectively. Among the gram-positive species, 88 and 92.5% of the isolates were sensitive to cefprozil and cefpirome, respectively. Cefepime and fleroxacin demonstrated the highest gram-negative activity with 85 and 89%, respectively, of the isolates being sensitive. The results of this study highlighted cefepime and cefpirome, which showed high overall in vitro activity against 79 and 88%, respectively, of the isolates tested.

Post-antibiotic effect of ceftazidime, ciprofloxacin, imipenem, piperacillin and tobramycin for Pseudomonas cepacia.

The post-antibiotic effects (PAE) of ceftazidime, ciprofloxacin, imipenem, piperacillin and tobramycin were studied for ten strains of Pseudomonas cepacia isolated from patients with cystic fibrosis. Antibiotic concentrations used for exposure were either the MIC of each agent for the sensitive isolates or the recommended sensitivity breakpoint concentrations for the resistant isolates. After 2 h of exposure, cultures were rapidly diluted 1000-fold to eliminate the antibiotic. Out of the ten isolates, there were eight sensitive to ceftazidime, six to ciprofloxacin, six to imipenem, nine to piperacillin and five to tobramycin. All antibiotics tested demonstrated PAE for some isolates of P. cepacia, however, each antibiotic failed to produce a PAE for at least one isolate. The mean PAE was 1.35 h for ceftazidime, 2.38 h for ciprofloxacin, 2.39 h for imipenem, 2.16 h for piperacillin and 1.77 h for tobramycin. Imipenem demonstrated PAE of > or = 0.5 h for all sensitive isolates tested; ceftazidime, piperacillin, ciprofloxacin and tobramycin demonstrated PAE of > or = 0.5 h for 6/8, 8/9, 5/6 and 2/5 sensitive isolates, respectively. These data indicate that several antibiotics have significant (> or = 0.5 h) PAE for isolates of P. cepacia.

Legionella lansingensis sp. nov. isolated from a patient with pneumonia and underlying chronic lymphocytic leukemia.

A Legionella-like organism, strain 1677-MI-H, was isolated from the bronchoscopy washings of a patient with pneumonia who had a 2-year history of progressive, chronic lymphocytic leukemia. The growth characteristics, cellular fatty acids, and ubiquinone content of the isolate were consistent with those for Legionella spp. The isolate was serologically distinct in the slide agglutination test with absorbed antisera. DNA hybridization studies showed that strain 1677-MI-H (ATCC 49751) represents a new Legionella species which is named Legionella lansingensis.

TestPack Strep A kit for the rapid detection of group A streptococci on 11,088 throat swabs in a clinical pathology laboratory.

Results obtained with Abbott Laboratories' TestPack Strep A, a rapid test kit to detect group A streptococcal antigen on throat swabs, were compared with the culture results. All tests were performed by American Society of Clinical Pathology-registered technologists in a large clinical laboratory. A total of 11,088 throat swabs were tested; 9,161 belonged to pediatric patients and 1,927 to adults. For TestPack Strep A, the study demonstrated a sensitivity value of 0.91 and a specificity value of 0.96; positive predictive value and negative predictive values were 0.82 and 0.98, respectively. These data indicate that even when performed by experienced technologists, in a laboratory setting, approximately 1 of 10 patients with group A streptococcal tonsillopharyngitis will be missed if physicians rely solely on this direct antigen test. A backup culture on all patients who are negative by a rapid antigen detection test is recommended.

Cytomegalovirus infection and excretion in residents of a nursing home.

Cytomegalovirus (CMV), following primary infection, usually remains latent with the potential for reactivation and excretion in saliva and urine. The prevalence of CMV excretion has not been studied among the elderly. This study followed 54 nursing home residents (mean age 83 years and medically stable, but with a wide spectrum of medical conditions). Over a 6 month period these subjects were serially tested for viral excretion in saliva and urine and for CMV antibody. While approximately 93% of the residents tested were sero-positive, indicating previous CMV infection, there was no evidence of viral excretion in any resident during the study period. Therefore, it is unlikely that the elderly nursing home residents will prove to be a source of CMV to the health care workers or to their family members.

Evaluation of microparticle enzyme immunoassays for immunoglobulins G and M to rubella virus and Toxoplasma gondii on the Abbott IMx automated analyzer.

The ability of the Abbott IMx automated analyzer to detect immunoglobulin G (IgG) and IgM antibodies to rubella virus and to Toxoplasma gondii was compared with the abilities of RUBAZYME, RUBAZYME-M, ABBOTT TOXO-G enzyme immunoassay, and ABBOTT TOXO-M enzyme immunoassay, respectively. Specimens that produced discordant results were evaluated by RUBACELL II, Behring Enzygnost-Rubella enzyme-linked immunosorbent assay, Behring Enzygnost Toxoplasmosis/IgG, and bioMerieux Toxo-ISAGA (immunosorbent agglutination assay), respectively. After resolution of discordant results, IMx Rubella IgG, IMx Rubella IgM, IMx Toxo IgG, and IMx Toxo IgM antibody assays had sensitivities of 99.9, 100, 98.0, and 100%; specificities of 98.9, 99.0, 97.5, and 98.7%; and accuracies of 99.8, 99.3, 97.8, and 98.8%, respectively.

Coxsackie B-2 virus infection in rat beating heart cell culture.

Beating rat heart cultures were prepared in vitro and infected with Coxsackie B-2 virus. The cells were evaluated in the post-infected period for changes in cardiac enzymes, alterations in beating frequency and cytotoxicity as measured by chromium 51 (51Cr) release. The cardiac enzymes, lactate dehydrogenase (LDH) and aspartate aminotransferase (AST) were measured in infected and uninfected controls over a period of 120 h. Enzyme levels in the infected cells remained essentially the same for the first 42 h as compared to the controls. At this time, the LDH levels increased rapidly reaching 116 +/- 24.8 U/l while the controls remained at 46.9 +/- 9.7 U/l. Aspartate aminotransferase levels increased at a slower rate and obtained a level of 104 +/- 20.2 U/l compared to 66.6 +/- 13.2 U/l in the control. Visual evidence of cellular damage as measured by decreased beating frequencies and the appearance of cytopathic effect was first noted at 42 h post-infection. Complete loss of cardiac beats and maximal viral cytopathic effect occurred at 96 h post-infection. Cardiac cellular damage as measured by cytotoxicity assay was found to parallel those changes seen in cardiac enzymes. No significant changes in cytotoxicity were observed for the first 24 h; however, at 48 h increased release of 51Cr was noted and visual evidence of viral replication also was present. The cardiac enzyme changes noted in beating rat heart cells appear to be similar to those changes reported in patients with viral-induced myocardial disease.(ABSTRACT TRUNCATED AT 250 WORDS)

A solid-phase enzyme immunoassay in detection of cervical gonorrhea in a low-prevalence population.

An evaluation of a solid-phase enzyme immunoassay (Gonozyme) for detection of gonococcal antigen in cervical swab specimens was undertaken in 504 asymptomatic women undergoing routine gynecologic examination. The immunoassay was positive in all seven women with culture-proven gonorrhea. Negative immunoassay results were obtained in 482 of the 497 women with negative cultures (97.0 percent specificity). The enzyme immunoassay's performance equals or exceeds that of other rapid alternative methods of diagnosing cervical gonorrhea such as Gram stain or limulus lysate assay. Its usefulness, however, is limited by less than 100 percent specificity, particularly in low-prevalence populations. More studies are needed to ascertain the performance of both this immunoassay and modified Thayer-Martin culture techniques in diagnosing cervical gonorrhea in low-prevalence populations.

Collaborative evaluation of the Abbott Avantage system for identification of frequently isolated nonfermentative or oxidase-positive gram-negative bacilli.

The capability of the Abbott Avantage system to identify 10 species of commonly isolated glucose nonfermentative or oxidase-positive gram-negative bacilli in a 5-h test period was evaluated in a collaborative study. The Avantage nonenteric data base uses 20 biochemical test reactions performed in an expanded Abbott bacterial identification cartridge plus the results of a manual oxidase test. The species included in the Avantage data base are Acinetobacter anitratus, Acinetobacter Iwoffi, Aeromonas hydrophila, Flavobacterium meningosepticum-IIb group, Pseudomonas aeruginosa, Pseudomonas cepacia, Pseudomonas fluorescens-putida group, Pseudomonas maltophilia, Pasteurella multocida, and Plesiomonas shigelloides. The collaborative study included the testing of 200 coded challenge strains in all three laboratories and the subsequent testing of an additional group of 100 to 200 clinical isolates recovered independently by each laboratory. Reference identifications for all isolates were determined by conventional biochemical test reactions. The overall accuracy of identification of the coded challenge strains for the three laboratories was 97%, whereas 95% of 437 clinical isolates and selected stock cultures of clinical derivation were identified correctly.

Hepatic granuloma due to a nymph of Linguatula serrata in a woman from Michigan: a case report and review of the literature.

There have been seven cases of human infection by nymphs of Linguatula serrata reported from the United States. Only three of these, however, are proven to be autochthonous. We report a rare case of hepatic granuloma due to a nymph of L. serrata in a woman from Michigan. She had never left the continental United States.

Evaluation of the updated MS-2 Bacterial Identification system in comparison with the API 20E system.

The recently updated MS-2 Bacterial Identification system software (Abbott Laboratories, Diagnostic Division, Irving, Tex.) was compared with the original MS-2 Bacterial Identification software and the API 20E, using 968 strains of Enterobacteriaceae. The updated MS-2 software correctly identified 94.4% of the isolates tested. API 20E and the original MS-2 software correctly identified 91 and 85.3% of the strains, respectively. MS-2 responses were considered to be equivocal (needing additional tests for verification) if the percent likelihood values were less than 80%. The percentage of equivocal responses was reduced from 6.5% with the original software to 2.2% with the updated software, and the percentage of incorrect identifications was reduced from 8.2 to 3.4% with the original and updated software, respectively. Organisms belonging to 25 taxonomic groups were tested. Direct comparison of the two MS-2 programs showed that the updated MS-2 software increased the identification accuracy of Salmonella spp., Enterobacter cloacae, Providencia stuartii, Escherichia coli, Shigella spp., Klebsiella pneumoniae, Serratia marcescens, Proteus mirabilis, and Acinetobacter calcoaceticus. A decrease in accuracy was seen with Citrobacter freundii, Hafnia alvei, Enterobacter agglomerans, and Yersinia pseudotuberculosis when the updated software was used. The remaining 12 taxonomic groups were not affected by the software changes. The updated MS-2 software appears to significantly improve the identification accuracy of the MS-2 Bacterial Identification system.

Enhanced detection of bacteremia with a new BACTEC resin blood culture medium.

In this multicenter study, 621 sets of blood culture specimens were drawn from 280 patients who were suspected of being septic and who were receiving antimicrobial therapy. Equal volumes of each specimen were inoculated into BACTEC 6B and 16B media. The 16B medium contained adsorbent and cationic resins for neutralizing the effects of the drugs. Of the 621 sets drawn, there were 72 positive cultures in 16B and 52 positive cultures in 6B. In 23 cases the organism was detected only in the 16B medium, and in 3 cases the organism was detected in 6B only. The remaining 49 positives were detected in both culture bottles. In 13 of these 49 cultures, detection in 16B was made between 1 and 5 days earlier than in 6B, whereas 3 of 49 specimens were detected 1 day earlier in 6B; the remaining 33 cultures became positive at approximately the same time in both media. There were a total of 43 patients with positive cultures in this study. Of these patients, 28 had sepsis detected in both the 16B and 6B media. The 6B medium alone detected an additional three cases of sepsis, and the 16B resin medium alone identified 12 additional cases. Supplementary culturing of samples from patients receiving antimicrobial therapy significantly increased the number of positive cultures and positive patients, as well as significantly shortening the time to positivity in these cultures.

Antimicrobial resistance of Shigellae isolated in Michigan.

Patterns of antimicrobial resistance were studied for 213 strains of shigellae isolated in rural and urban areas of Michigan by quantitative techniques: 66% of these organisms were resistant to ampicillin, tetracycline, cephalexin, or chloramphenicol or had multiple resistance to various combinations of these antibiotics. The incidence of resistant organisms was higher in the Detroit-Wayne County area, which is the most urban part of the state. Nalidixic acid and oxolinic acid were noted to be quite effective in vitro against shigellae and perhaps warrant further clinical study as potential agents for therapy of shigellosis, especially in view of the appearance of isolates with multiple resistance. Sulfamethoxazole alone was effective against only 62% of the Shigella isolates tested, but mixture with trimethoprim in a 20:1 ratio yielded a highly active in vitro combination.