Search

The lack of an adequate typing system hampers our understanding of the epidemiology of infections caused by coagulase-negative staphylococci (CoNS). CoNS have become recognized as important nosocomial pathogens and the principal cause of infections associated with invasive devices. Sensitive, specific, and convenient methods are needed to evaluate whether implementing infection control guidelines reduces the risk of nosocomial infections from CoNS and other pathogens. The Microbial Identification System (MIDI) (Microbial ID Inc., Newark, Del.), a semiautomated system for fatty acid methyl ester analysis, shows considerable promise for clinical and epidemiologic applications. Its predictive accuracy and reliability were tested by using epidemiologically related and replicated CoNS isolates as well as CoNS from epidemiologically unrelated clinical infections, which were obtained from five established hospital culture collections in diverse geographic locations. Two hundred isolates were fully characterized in 5 days by one person using MIDI, and the results were similar to those produced by more expensive and time-consuming conventional typing methods. MIDI appears to be a useful screening tool that could be used before more expensive and labor-intensive molecular methods. It offers important advantages to hospital epidemiologists and clinical microbiologists who must identify and type CoNS isolates.

The antipseudomonal activities of ceftriaxone (CEF) or ceftazidime (CAZ), each combined with tobramycin (TOB) or netilmicin (NET), against 90 clinically significant Pseudomonas aeruginosa isolates were examined both by checkerboard and time-kill assays. As expected, susceptibility testing of single antibiotics by agar dilution demonstrated good activity for CAZ (89% susceptible), TOB (94%), and NET (58%), but poor activity for CEF (15%). Checkerboard studies revealed striking synergy (FIC indices < or = 0.5) for CEF, however, in combination with either TOB (72%) or NET (81%), compared with CAZ-TOB (44%) or CAZ-NET (60%) (P < 0.01, respectively). No antagonism (FIC indices > or = 4) was found in any of these combinations. The MIC90s of CEF, CAZ, or aminoglycosides in the combinations were reduced at least fourfold: CEF, from > 128 to 32 mg/liter; CAZ, from 16 to 4 mg/liter; TOB, from 4 to 0.5 mg/liter; and NET, from 32 to 4 mg/liter. With CEF and NET, the percentage of strains sensitive to < or = 8 mg/liter of both drugs alone and in combination increased from 9% to 69%. Results of the time-kill assay for CEF-NET agreed reasonably well with the checkerboard method (Spearman rank correlation coefficient, 0.40, P < or = 0.01), and generated a bactericidal outcome in 60% (24 of the 40 isolates), when tested with combinations at 1/4 MBC of either antibiotic alone. Importantly, concentrations of CEF and aminoglycoside combinations that demonstrated synergy by either checkerboard or time-kill assays were achievable in serum clinically. These data suggest a unique interaction of CEF-aminoglycoside combinations against P. aeruginosa.(ABSTRACT TRUNCATED AT 250 WORDS)

The rapid ID32A kit (bioMérieux Vitek, Inc., Hazelwood, Mo.) was evaluated for its ability to identify Peptostreptococcus species compared with conventional biochemical tests and gas-liquid chromatography (Virginia Polytechnic Institute), the current "gold standard" method. A total of 5 Peptostreptococcus American Type Culture Collection strains and 95 clinical isolates comprising Peptostreptococcus anaerobius, P. asaccharolyticus, P. magnus, P. micros, and P. prevotii isolates were included for analysis. Overall, the sensitivity and specificity of the rapid ID32A kit in the identification for five Peptostreptococcus species compared with the Virginia Polytechnic Institute method were 93 and 80%, respectively. All P. anaerobius (n = 20) and P. asaccharolyticus (n = 25) isolates were identified with 100% sensitivity and 100% specificity. For the identification of P. magnus (n = 24) and P. micros (n = 19), the rapid ID32A kit was 100% sensitive for both species; the specificity for P. magnus was 95.8% and that for P. micros was 57.9%. The sensitivity and specificity of the rapid ID32A kit for identification of P. prevotii (n = 12) were poor (41.7 and 8.3%, respectively). The rapid ID32A kit is a useful method for the rapid differentiation of P. anaerobius and P. asaccharolyticus from other Peptostreptococcus spp. Conventional methods should be used to identify to the species level isolates of P. magnus, P. micros, and P. prevotii.

Subtype classification based on the use of monoclonal antibodies to the class 1 outer membrane protein combined with techniques such as multilocus enzyme electrophoresis remains the standard method of characterizing isolates during outbreaks of invasive meningococcal disease. We developed a rapid typing method based on the restriction fragment length polymorphisms (RFLPs) within the polymerase chain reaction (PCR) product of the porA gene, which encodes the class 1 outer membrane protein, reflecting genotypic rather than phenotypic variability between strains. Forty-five isolates of invasive Neisseria meningitidis obtained from October 1990 to April 1992 were studied after randomization and coding. Included among these were isolates from a local outbreak that resulted in a mass vaccination program. PCR amplification for each isolate was followed by restriction digestion with the following enzymes in the indicated sequence: HaeIII, RsaI, HinfI, HpaII, and AluI. Eighteen different patterns were demonstrated on the basis of RFLPs, whereas only seven groups were identified after standard subtyping. The most common isolate identified by serosubtyping was serogroup C, serotype 2a, subtype P1.2 (C:2a:P1.2) (38%). Thirteen (76%) of these group C isolates shared a common RFLP pattern after digestion with the five restriction enzymes. We were able to further differentiate strains of C:2a:P1.2 with electrophoretic type 5 from electrophoretic types 1, 9, and 15 that occurred during an apparent outbreak. We were also able to characterize 15 isolates (33%) which could not be subtyped with monoclonal antibodies. Our method offers a convenient alternative to standard subtyping procedures and is particularly useful in outbreak situations in which rapid characterization of N. meningitidis is essential so that rational public health policy regarding preventative measures can be formulated.

An improved method for producing highly purified toxic shock syndrome toxin 1 (TSST-1) by preparative isoelectric focusing in a Bio-Rad Rotofor cell and then chromatofocusing is described. Purification to homogeneity was confirmed by silver staining after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE; 50 micrograms of protein was loaded), by immunoblotting with polyclonal rabbit antiserum raised against the crude culture supernatant used for purification, and by autoradiography after iodination and SDS-PAGE. Biologic activity was demonstrated by mitogenicity and cytokine induction (tumor necrosis factor alpha [TNF-alpha], interleukin 1-beta [IL-1 beta], and IL-6) of human peripheral blood mononuclear cells (PBMCs) and by lethality in New Zealand White rabbits following subcutaneous infusion. In contrast to commercial TSST-1 preparations, our TSST-1 preparation required the presence of both monocytes and T cells for the induction of TNF-alpha and IL-1 beta from human PBMCs. A 46-kDa contaminating protein in the commercial TSST-1 preparation, identified as staphylococcal lipase, was likely responsible for the induction of TNF-alpha and IL-1 beta from human monocytes in the absence of T cells, a biologic activity falsely attributed to purified TSST-1. Our improved purification procedure for TSST-1 provides a high yield and is both more rapid and less labor intensive than previously reported methods. Furthermore, our studies clearly demonstrate the need for stringent methods of purity assessment of TSST-1 preparations before ascribing to them their potent biologic activities.

To evaluate the clinical efficacy of interferon-alpha in hepatocellular carcinoma, 71 adult Chinese patients with histologically proven inoperable hepatocellular carcinoma were randomized to receive recombinant interferon-alpha 2a (50 x 10(6) IU/m2) intramuscularly three times a week (n = 35) or no antitumor therapy (n = 36). The survival of interferon-alpha-treated patients was significantly better than that of patients who received no antitumor therapy (p = 0.0471); median lengths of survival were 14.5 and 7.5 wk, respectively. Objective tumor regression greater than 50% was observed in 31.4% (11 of 35) of patients receiving interferon-alpha. Interferon-alpha induced tumor regression greater than 50% in 11 (31.4%) patients. Compared with the group receiving no antitumor therapy, the interferon-alpha therapy group had more tumor regression (p < 0.0001) and less tumor progression (p = 0.001). This high-dose interferon-alpha therapy was relatively well tolerated; only 34.3% of patients required reduction of dosage by one third or one half because of persistent fatigue. Two patients with diabetes mellitus (one also had tabes dorsalis) exhibited mental deterioration that might have been partially attributable to interferon-alpha therapy. We conclude that interferon-alpha is useful in a proportion of Chinese patients with inoperable hepatocellular carcinoma, both in prolonging survival and in inducing tumor regression.

Prosthetic valve endocarditis remains an infrequent but serious complication of cardiac valvular replacement. Prosthetic valve endocarditis was diagnosed in 56 (1.8%) of 3200 patients in whom one or more porcine bioprostheses were implanted between 1975 and 1988. Of the 56 patients with prosthetic valve endocarditis, there were 40 men and 16 women, with a mean age at initial implantation of 57 years (27 to 81 years). Of the 56 patients, 6 were initially treated for native valve endocarditis. There were 8 cases of early prosthetic valve endocarditis (defined as occurring less than 60 days after initial surgical intervention) and 48 cases of late prosthetic valve endocarditis (occurring after 60 days). The overall mortality rate of the 56 patients was 32% (18 patients). Of the 8 patients with early prosthetic valve endocarditis, 6 (75%) died. Of the 48 patients with late prosthetic valve endocarditis, 12 (25%) died. The predominant organisms were Staphylococcus epidermidis (12 cases), Streptococcus viridans (8 cases) and Staphylococcus aureus (7 cases). The presence of hemodynamic compromise, including congestive heart failure, septic embolism, persistent sepsis, and echocardiographic evidence of vegetations, dictated the mode and timing of the addition of surgical intervention to medical therapy. The survival rate for medically and surgically treated patients with late prosthetic valve endocarditis was 91% (20 patients); none of the patients with early prosthetic valve endocarditis survived (all had severe hemodynamic compromise). We analyzed 18 factors for the prediction of early and late death. The predictors of death by univariate analysis for both early and late prosthetic valve endocarditis were age, diagnosis time, renal status, sepsis, management mode, fever, dental procedures, and dental prophylaxis. The predictors by multivariate analysis were age, diagnosis time, renal status, and management mode for early prosthetic valve endocarditis, and only diagnosis time for late prosthetic valve endocarditis. Annular abscess formation occurred in 27% of the patients. There were no complex aortic or mitral reconstructions. There was one reoperation for recurrent and residual endocarditis. There was one late death as a result of recurrent prosthetic valve endocarditis. We advocate early diagnosis and aggressive combined medical and surgical treatment before the development of hemodynamic compromise and other characteristic signs when the culprit organisms are Staphylococcus aureus, gram-negative organisms, and Candida albicans.

Gram-positive infections have become prevalent among neutropenic patients with cancer. A prospective, randomized, double-blind trial of teicoplanin, 6 mg/kg every 12 h for three doses then every 24 h, versus vancomycin hydrochloride, 15 mg/kg every 12 h, in the empirical treatment of febrile neutropenic patients was undertaken among 50 consecutive patients with haematological malignancy. The patients also received piperacillin sodium, 3 g every 4 h, and tobramycin sulphate, 1.5-2 mg/kg every 8 h. Both groups (25 teicoplanin and 25 vancomycin) were comparable in age, sex, renal function, underlying disease and concurrent therapy. Among 22 patients (44%) with culture-proven infection, Gram-positive organisms were isolated in 15 (9 with bacteraemia) and Gram-negative in 11 (4 with bacteraemia). Mixed or polymicrobial infection occurred in 8 patients. Serum 1-h peak and trough levels at steady state were 41 +/- 15 and 12 +/- 3 mg/l for teicoplanin (at 14 +/- 4 days), and 40 +/- 10 and 8 +/- 5 mg/l for vancomycin (at 0.9 +/- 0.6 days). Mean elimination half-life and apparent volume of distribution at steady state were 80.5 +/- 21.5 h and 1.4 +/- 0.8 l/kg for teicoplanin, and 5.6 +/- 1.8 h and 0.6 +/- 0.2 l/kg for vancomycin. Empirical antimicrobial therapy was successful in 23 teicoplanin and 21 vancomycin patients, respectively (p = 0.67; two-tailed Fisher's exact test). Nephrotoxicity (serum creatinine > 110 mmol/l), however, was more common among vancomycin patients (10 versus 2; p = 0.02), while termination of treatment due to adverse effects was also more common among vancomycin patients (10 versus 2; p = 0.02).(ABSTRACT TRUNCATED AT 250 WORDS)

To further characterize the clinical spectrum of nonmenstrual toxic shock syndrome (NMTSS), we constrasted and compared the clinical and laboratory features of 24 patients with NMTSS with those of 21 patients with menstrual TSS (MTSS), using univariate and stepwise discriminant analyses. In contrast to patients with MTSS, those with NMTSS comprised a heterogeneous group with varying host factors and clinical presentations. The NMTSS group differed from the MTSS group in terms of the frequency of prior antimicrobial treatment (46% vs. 16%; P = .05), the rate of nosocomial acquisition (65% vs. 0; P = .0001), and the time of onset of fever and rash in relation to the initial symptoms (P = .005 and .03, respectively, with earlier onset in the NMTSS group). In addition, NMTSS patients experienced more frequent renal and CNS complications and less frequent musculoskeletal involvement (P = .07 in all three cases). Stepwise discriminant analysis identified four variables (delayed onset of TSS symptoms after precipitating injury or event, more frequent CNS manifestations, less frequent musculoskeletal involvement, and higher degree of anemia) differentiating NMTSS patients from MTSS produced TSS toxin 1 (TSST-1) with comparable frequency (62% vs. 84%; P = .2), but production of staphylococcal enterotoxin A (SEA) was less common in NMTSS than in MTSS (33% vs. 74%; P = .01). Furthermore, MTSS-associated isolates more commonly coexpressed TSST-1 and SEA than did NMTSS-associated isolates (68% vs. 28%; P = .01).(ABSTRACT TRUNCATED AT 250 WORDS)

We previously demonstrated that the induction by staphylococcal toxic shock syndrome toxin 1 (TSST-1) of tumor necrosis factor alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) secretion by human monocytes requires direct T cell-monocyte contact. In the present study, a role for the adhesion molecule lymphocyte function associated antigen 1 (LFA-1) in TSST-1-induced cytokine secretion by human monocytes among 12 normal healthy donors was investigated. Monoclonal antibodies to the alpha chain (anti-CD11a) and to the beta chain (anti-CD18) of LFA-1 significantly inhibited TSST-1-induced TNF-alpha and IL-1 beta secretion (P < 0.025; Wilcoxon signed-rank test, two tailed), while a control monoclonal antibody directed against the monocyte CD14 antigen had no effect. These results suggest that LFA-1 may play an important role in the secretion of TNF-alpha and IL-1 beta by TSST-1-stimulated human monocytes, likely by promoting cell-cell adhesion between monocytes and lymphocytes.

These guidelines deal with the evaluation of anti-infective drugs for the treatment of respiratory tract infections. Five clinical entities are described: streptococcal pharyngitis and tonsillitis, otitis media, sinusitis, bronchitis, and pneumonia. A wide variety of microorganisms are potentially pathogenetic in these diseases; these guidelines focus on the bacterial infections. Inclusion of a patient in a trial of a new drug is based on the clinical entity, with the requirement that a reasonable attempt will be made to establish a specific microbial etiology. Microbiologic evaluation of efficacy requires isolation of the pathogen and testing for in vitro susceptibility. Alternatively, surrogate markers may be used to identify the etiologic agent. The efficacy of new drugs is evaluated with reference to anticipated response rates. Establishment of the microbial etiology of respiratory tract infections is hampered by the presence of "normal flora" of the nose, mouth, and pharynx, which may include asymptomatic carriage of potential pathogens. This issue is addressed for each category of infection described. For example, it is suggested that for initial phase 2 trials of acute otitis media and acute sinusitis tympanocentesis or direct sinus puncture be used to collect exudate for culture. Acute exacerbations of chronic bronchitis also present difficulties in the establishment of microbial etiology. These guidelines suggest that clinical trials employ an active control drug but leave open the possibility of a placebo-controlled trial. For pneumonia, the guidelines suggest the identification and enrollment of patients by the clinical type of pneumonia, e.g., atypical pneumonia or acute bacterial pneumonia, rather than by etiologic organism or according to whether it was community or hospital acquired. For each respiratory infection, the clinical response is judged as cure, failure, or indeterminate. Clinical improvement is not acceptable unless quantitative response measures can be applied.

Infected pressure and diabetic ulcers are encountered frequently by clinicians caring for the geriatric population. These infections are polymicrobial and are often complicated by sepsis syndrome and osteomyelitis. Together, these infections account for significant morbidity and mortality in elderly persons. A team approach to management is essential for the clinician, and efforts should focus primarily on prevention.

The association between staphylococcal enterotoxin (SE) B and toxic shock syndrome (TSS) toxin 1 (TSST-1) in menstrual and nonmenstrual TSS was examined. Production of SEB and TSST-1 in the culture supernatants from 344 Staphylococcus aureus isolates was quantitated by noncompetitive ELISA (lower detection limit, 0.5 ng/mL for both assays). In the ELISA for SEB, cross-reactive antibodies to SEC were removed by absorption in a biotin-streptavidin-agarose column (SEC1 at concentrations to 100,000 ng/mL could not be detected). Among TSST-1-negative isolates, SEB production in nonmenstrual TSS isolates (8/13, 62%) was more prevalent than that in either menstrual TSS isolates (1/4; P = .3), non-TSS infections (15/103, 15%; P less than .001), or asymptomatic carriers (14/105, 13%; P less than .001). Expression of SEB and TSST-1 was usually mutually exclusive (only 1.5% of 344 isolates produced both SEB and TSST-1). Multilocus enzyme electrophoretic typing (ET) suggested a clonal origin for both SEB-(55% of ET-5) and TSST-1 (76% of ET-19)-producing isolates. Thus, SEB may be an important cause in TSS where TSST-1 is not elaborated, especially in nonmenstrual TSS isolates.

Staphylococcal toxic shock syndrome toxin-1 (TSST-1) as well as staphylococcal enterotoxin A (SEA) and B (SEB) have recently been shown to bind directly to the class II major histocompatibility antigen, HLA-DR. Whereas others have characterized TSST-1 and SEA binding to HLA-DR on transfected L cells or B lymphoma cell lines, we sought evidence for direct binding of TSST-1 and SEA to HLA-DR on purified human monocytes. A single class of high-affinity receptors was found for both TSST-1 (dissociation constant (Kd) 40 nM, 3.4 x 10(4) receptors per cell) and SEA (Kd 12 nM, 3.2 x 10(4) receptors per cell) on normal human monocytes. Affinity cross-linking of 125I-labeled toxins to monocytes revealed the presence of two membrane protein subunits with molecular masses consistent with the alpha and beta chains of human HLA-DR (35 and 28 kDa, respectively). The anti-HLA-DR monoclonal antibody L243, but not L203 or 2.06, inhibited radiolabeled toxin binding to human monocytes and neutralized the mitogenic response of human T lymphocytes to both toxins. However, L243 was consistently more effective in blocking radiolabeled TSST-1 than SEA binding to human monocytes from the same donors, suggesting that TSST-1 and SEA may be binding to overlapping epitopes rather than to the same epitope on HLA-DR. Because TSST-1 and SEB bind to distinct epitopes on HLA-DR and because SEA cross competes with both TSST-1 and SEB on the HLA-DR receptor, we postulate that SEA occupies a binding site within HLA-DR that overlaps both TSST-1 and SEB.(ABSTRACT TRUNCATED AT 250 WORDS)

The signal transduction pathways by which staphylococcal toxic shock syndrome toxin 1 (TSST-1) induces tumor necrosis factor alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta) secretion were examined with various protein kinase inhibitors. TNF-alpha secretion by normal human monocytes and T cells in response to TSST-1 was suppressed by inhibitors of protein kinase C (H7) and tyrosine kinases (genistein). In contrast, the secretion of IL-1 beta was blocked by a cyclic AMP- and cyclic GMP-dependent kinase inhibitor (HA1004) as well as by H7 and genistein. These results suggest that the secretion of TNF-alpha and IL-1 beta may be differentially regulated by TSST-1 and that protein kinases play an important role in mediating cytokine responses to the toxin.

Staphylocoagulase, a major phenotypic determinant of Staphylococcus aureus, exists in multiple allelic forms, in part because of the existence of gene variants within the 3'-end coding region. This region contains a series of repeating 81-bp DNA sequences which differ both in the number of tandem repeats and the location of AluI restriction sites among different isolates. Utilizing this finding, we developed a novel typing method for S. aureus based on polymerase chain reaction amplification of the variable region of the coagulase gene followed by AluI restriction enzyme digestion and analysis of restriction fragment length polymorphism (RFLP). Among 30 S. aureus isolates studied initially, a total of 10 distinct RFLP patterns were observed. There was excellent correlation of the RFLP patterns with typing of these isolates by multilocus enzyme electrophoresis at 20 chromosomal loci. This coagulase RFLP method was used to analyze an additional 39 S. aureus isolates and successfully traced the source of an outbreak of methicillin-resistant S. aureus infections at a local hospital.

Highly purified staphylococcal toxic shock syndrome toxin 1 (TSST-1) was tested for its ability to induce the cytokines tumor necrosis factor (TNF) and interleukin-1 (IL-1) from fractionated human peripheral blood mononuclear cells prepared from seven healthy donors. Highly purified monocytes alone or T lymphocytes alone did not produce TNF or IL-1 when incubated with TSST-1 at 37 degrees C for up to 72 h. However, the addition of 10 micrograms of TSST-1 per ml to a 1:1 mixture of monocytes and T cells resulted in significant TNF (predominantly TNF-alpha) and IL-1 beta production after 24 h at 37 degrees C. The nature of the monocyte/T-cell interaction did not appear to involve gamma interferon (IFN-gamma), since 10 micrograms of rabbit anti-IFN-gamma per ml did not neutralize TNF-alpha production after TSST-1 induction. Similarly, L243, a monoclonal antibody to HLA-DR which blocks TSST-1 binding to monocytes, did not inhibit TNF-alpha production following TSST-1 induction. However, direct contact between monocytes and T cells was required, since physical separation of cells in double-chamber culture wells abolished TNF-alpha secretion after TSST-1 stimulation. Furthermore, paraformaldehyde fixation of either monocytes or T cells prior to addition to viable T cells or monocytes, respectively, also abolished TNF-alpha secretion, suggesting that aside from cell contact, soluble factors were also involved. Our results suggest that cytokine production involves more than binding of TSST-1 to its receptor on monocytes alone and that cell contact with T cells and the release of a soluble factor(s) other than IFN-gamma may be essential for the induction of cytokines by this toxin.

A prospective, randomized, and double-blind study comparing teicoplanin with vancomycin in the initial management of febrile neutropenic patients was conducted. Teicoplanin was administered at 6 mg per kg of body weight every 24 h (q24h) intravenously (i.v.) after initial loading at 6 mg/kg q12h for three doses. Vancomycin was administered at 15 mg/kg q12h i.v. Patients also received piperacillin (3 g q4h i.v.) and tobramycin (1.5 to 2.0 mg/kg q8h i.v.). Of 53 patients enrolled, 50 were judged to be evaluable. Among these, 25 received teicoplanin and 25 received vancomycin. At enrollment, both groups were comparable in age, sex, renal function, underlying hematologic condition, and concurrent therapy. Both groups had similar sites of infection and microbial pathogens. Empirical antimicrobial therapy resulted in the cure of or improvement in 23 (92%) teicoplanin patients and 21 (84%) vancomycin patients (P = 0.67). Failures occurred with two vancomycin patients but no teicoplanin patients. Clinical response was indeterminate for two patients in each group. Adverse reactions occurred significantly more often in the vancomycin group than in the teicoplanin group (P = 0.01), and these reactions required the termination of the study regimens of 6 vancomycin versus 0 teicoplanin patients (P = 0.02). Nephrotoxicity was observed more frequently in the vancomycin group (10 versus 2 patients; P = 0.02). Subgroup analysis revealed a significant deterioration of renal function when vancomycin and cyclosporin A, but not teicoplanin and cyclosporin A, were used concurrently (P = 0.02). Among patients who received vancomycin and amphotericin B or teicoplanin and amphotericin B concurrently, deterioration in renal function was equivalent in both groups. Teicoplanin in the dosage employed was tolerated better than vancomycin in the empirical treatment of fever and neutropenia in our patient population.

Objective: A method that would allow in situ comparison of the degrees of adherence to genital epithelia by the biofilms of the normal flora., Subjects: Four healthy women., Setting: Departments of Biological Sciences, University of Calgary, and of Medicine, University of British Columbia., Methods: In situ, scraped specimens were taken from the vagina and ectocervix before and after vigorous vaginal washes, and colony counts of associated bacteria were compared. In vitro, cells from the vulva, vagina and ectocervix were vortexed, centrifuged and sonicated and remaining associated bacteria quantitated by light microscopy., Results: Anaerobic lactobacilli were notably tissue-adherent as colony counts of postwash specimens were comparable to those of their paired prewash specimens, but crucially were higher than those of their paired wash specimens (p less than 0.05, Wilcoxon signed rank test). However, vaginal and ectocervical coagulase-negative staphylococci and ectocervical Lancefield group B streptococci were loosely tissue-adherent, because counts in postwash specimens were lower than those in prewash or wash specimens (p less than 0.05, Wilcoxon signed rank test). In vitro, only vulvar scrapings and vaginal postwash specimens showed a significant decrease in associated bacteria after shear stressing (p less than 0.05, Wilcoxon signed rank test)., Conclusions: The normal flora of the female genitalia features both avidly and loosely tissue-adherent bacterial biofilm populations whose adherence can be influenced partly by their location. Our scraping/washing method can contribute to further characterisation of this phenomenon. The superior adherence of anaerobic lactobacilli may reflect a potential in maintaining or restoring normality.

Teicoplanin is a glycopeptide antibiotic with a mode of action and spectrum of activity similar to those of vancomycin. Its efficacy and tolerability as empiric therapy and its pharmacokinetic properties in neutropenic patients are being studied in a double-blinded, randomized trial in comparison with those of vancomycin. We report here a modified agar diffusion bioassay which is suitable for monitoring levels of either teicoplanin or vancomycin in serum during combination therapy with beta-lactams, aminoglycosides, and amphotericin B. Serum samples spiked with either teicoplanin or vancomycin gave reproducible results (mean coefficient of variation, 8.8%) regardless of the presence of tobramycin, amikacin, piperacillin, ceftazidime, amphotericin B, or their combinations. Among 25 patients who received teicoplanin at a dosing schedule of 6 mg/kg every 24 h intravenously, steady state was reached after 14.2 +/- 4.0 days, and 1-h peak and trough concentrations of teicoplanin in serum at steady state were 40.8 +/- 15.0 and 12.5 +/- 3.2 mg/liter, respectively. In contrast, among 25 patients who received vancomycin at a dosing schedule of 15 mg/kg every 12 h intravenously, steady state was reached by 24 h, and the 1-h peak and trough concentrations in serum were 37.5 +/- 15.6 and 8.3 +/- 3.8 mg/liter, respectively. The elimination half-lives for teicoplanin estimated by two separate approaches agreed closely with each other: 80.5 +/- 21.5 h by an accumulation model (M. Gilbaldi and D. Perrier, Pharmacokinetics, 2nd ed., p. 121, 1982) and 87.3 +/- 19.3 h as predicted from the degree of renal function (M. Rowland, Clin. Pharmacokinetic 18:184-209, 1990). These values were 14- to 15-fold higher than that for vancomycin (5.6 +/- 1.8 h). Since considerable variability was noted in the pharmacokinetic parameters for both teicoplanin and vancomycin among the individual patients, our data further emphasized the need for frequent monitoring of these drugs during empiric therapy of the febrile neutropenic patient.

The impact of recently recommended hospital infection control guidelines on Canadian acute-care hospitals is unknown. A confidential cross-sectional mailed survey of all acute-care Canadian hospitals was conducted to determine rates of receipt and adoption of published guidelines for Universal Precautions (UP) or Body Substance Isolation (BSI), rationale for adoption and knowledge of costs and benefits. Five hundred and seventy-nine of 943 sites (61%) responded (exceeding 80% in urban centers); 94% among hospitals with at least 300 beds and 57% among those under 300 beds. Seventy-four percent of responders claimed adoption of UP (65%) or BSI (9%), staff protection being their primary motivation. Adoption of either UP or BSI was associated with size (p less than .001), increasing progressively from 45% in the smallest group (less than 25 beds) to 84% in the largest (greater than or equal to 500 beds). Many hospitals introduced modifications and some substituted names other than UP or BSI in adopting a new strategy. In practice, UP and BSI now mean different things in different hospitals, and the distinction between them has become blurred. Furthermore, only 5% claiming adoption of a new strategy adopted all of the fundamental policies expected under UP or BSI. Receipt of guidelines was also correlated with size: one-third of hospitals under 200 beds had not received key publications defining UP and BSI. Only 19% claiming adoption of a new strategy indicated knowledge of cost implications. These results suggest a need for closer collaboration among hospitals and government agencies in developing uniform infection control policies, and for systematic evaluation of the cost and effectiveness of new strategies.

Binding of toxic shock toxin 1 (TSST-1) and staphylococcal enterotoxin A (SEA) to human peripheral blood mononuclear cells (PBMC) was investigated by using 125I-labeled ligands. Scatchard analyses revealed similar numbers of receptors (approximately 5,000 to 8,000) and similar dissociation constants (Kd, approximately 20 to 25 nM) per PBMC. SEA but not enterotoxin B, C1, C2, C3, D, or E significantly inhibited binding of 125I-TSST-1 to PBMC. Cross-competition of TSST-1 and SEA in binding assays suggests that they may bind to overlapping or separate epitopes on the same receptor.

Genetic relationships among 315 isolates of the bacterium Staphylococcus aureus expressing toxic shock syndrome toxin-1 (TSST-1) recovered primarily from humans with toxic shock syndrome (TSS) in five countries on two continents were determined by analyzing electrophoretically demonstrable allelic variation at 20 chromosomal enzyme loci. Forty-nine distinctive electrophoretic types (ETs), representing multilocus enzyme genotypes, were identified. Cluster analysis of the ETs revealed two major phylogenetic divisions separated at a genetic distance of 0.35 and seven branches diverging from one another at distances greater than or equal to 0.20. A single clone (ET 41) accounted for 88% of cases of TSS with a female urogenital focus and 53% of TSS cases involving nonurogenital (predominantly wound) infections. With few exceptions, strains representing different phylogenetic lines had characteristic TSST-1 gene (tst) restriction fragment length polymorphism patterns obtained by digestion of genomic DNA with Cla I. Strains recovered from ovine and bovine hosts with mastitis were genotypically distinct from the major human TSS clone. The expression of TSST-1 in cell lineages representing the total breadth of multilocus genotypic diversity in the species S. aureus as a whole is interpreted as evidence that the TSST-1 gene is evolutionarily old. The recovery of a single clone from the majority of individuals afflicted with TSS having a urogenital focus and from the genital tract of a large proportion of asymptomatic female carriers strongly suggests that this clone is especially well adapted for colonization of these anatomic sites.

Necrotizing fasciitis is a relatively uncommon severe soft tissue infection that is characterized by rapid widespread superficial fascial necrosis with undermining of surrounding soft tissue. Recent advances in anaerobic culture techniques have allowed identification of anaerobic organisms, which are now considered to have a vital role in the pathogenesis of this soft tissue infection. Therapy requires both rapid institution of a high level of antibiotics and a radical surgical incision and drainage procedure. All of the aerobic and anaerobic organisms isolated in the reported case of necrotizing fasciitis arising from a periapically infected mandibular third molar demonstrated in vitro sensitivity to penicillin.

The recent release, relatively high cost and potential adverse effects of parenterally administered metronidazole prompted a quality-of-use audit at a 1000-bed teaching hospital. Ninety-two courses of treatment in 81 inpatients during a 6-week period were studied. Appropriateness of therapy was assessed on the basis of published indications. Parenterally administered metronidazole was prescribed primarily in anaerobic and anaerobic-aerobic infections. It was used as frequently for prophylaxis as for therapy. Surgical services accounted for 95% of the treatment courses. Inappropriate use was noted in 27 (29%) of the courses: agents other than parenterally administered metronidazole were indicated in 12 (13%), while the dose, dosing interval or duration of treatment was suboptimal in 15 (16%). Substantial savings would be achieved if oral or rectal metronidazole therapy were substituted for intravenous therapy for perioperative prophylaxis in elective colorectal surgery. Written justification for use and automatic stop orders are recommended to improve the cost effectiveness of both prophylactic and therapeutic use of selected antimicrobial agents.

Toxic shock syndrome toxin-1 (TSST-1) is implicated as the major exotoxin associated with menstrual toxic shock syndrome. The role of TSST-1 in nonmenstrual TSS is less certain. We examined serum IgG responses to TSST-1 in 16 nonmenstrual (9 female, 7 male) and 14 menstrual TSS patients, and in 87 women and 66 men as age-matched healthy controls, using an enzyme-linked immunosorbent assay (ELISA). Relative ELISA titers were expressed as percent activity of a mid level serum standard tested concurrently. Based on 95% confidence estimates for predicting a negative titer (20.6 +/- 8.2%) using sera in which TSST-1 specific IgG was demonstrated to be absent by western blot, 24% of control women and 9% of control men lacked TSST-1 specific IgG in the random survey (p less than 0.05, Fisher's exact test). Relative titers in acute sera of menstrual TSS women (26.2 +/- 5.2%, mean +/- S.E.), but not nonmenstrual TSS women (71.8 +/- 18.6%), were significantly lower than those of control women (78.9 +/- 7.3%, p less than 0.01, Mann-Whitney test). Acute titers from male TSS patients (37.0 +/- 15.6%) were also significantly lower than those in control men (114.6 +/- 11.0% (p less than 0.05). Antibody titers from menstrual TSS women and TSS men remained low during convalescence. Nevertheless, seroconversion to TSST-1 was demonstrated by western blot in 7 of 10 patients in whom TSST-1 positive S. aureus was isolated, but in neither of two patients without toxigenic S. aureus.(ABSTRACT TRUNCATED AT 250 WORDS)

Seventy patients with postpartum endomyometritis were treated with either intravenous mezlocillin (16 gm/day) or ampicillin (8 gm/day) in a prospective, randomized, double-blind comparison. Endocervical dilatation was routinely performed. Clindamycin (2 gm/day) was added if patients failed to improve within 48 hours of beginning therapy. Pretreatment clinical and microbiologic profiles were comparable in the two groups. Bacteremia was documented in 21 patients (30%). Anaerobic cocci and Bacteroides spp. (non-B. fragilis) comprised 19 of 29 (65%) blood isolates. Thirty of 33 mezlocillin-treated patients (91%) and 30 of 37 ampicillin-treated patients (81%) responded to initial therapy (P greater than 0.4). Resolution was noted after the addition of clindamycin in all ten nonresponders; two of these patients also required surgical wound debridement. Objective parameters of clinical response were not significantly different in the two treatment groups. Side effects of mezlocillin therapy were minimal. We conclude that mezlocillin and ampicillin are equally effective and safe for therapy of postpartum endomyometritis. That mezlocillin was not superior to ampicillin, despite expanded activity against B. fragilis and members of Enterobacteriaceae, suggests that these pathogens are less important than was previously considered in postpartum endomyometritis.

Campylobacter fetus is a major cause of venereally transmitted abortion and sterility in ungulates, and a recently recognized, common enteric pathogen in man. The role of the organism as a cause of human fetal wastage has not been delineated. We present a case of bacteremic campylobacter infection in a pregnant woman, and review the published cases of campylobacteriosis in pregnancy and the perinatal period. Systemic maternal infection may present either as prolonged febrile illness or fulminant sepsis, and transplacental spread may result in abortion, stillbirth, or early neonatal meningitis. Enteritis that occurs in infants born to women with campylobacter diarrhea may represent fecal-oral spread at or near the time of delivery. With improved microbiologic techniques and greater awareness by physicians, the prevalence and importance of campylobacteriosis in pregnancy should become better appreciated.

An unusual case of a patient with primary meningococcal pericarditis presenting with tamponade is reported. tdespite repeated aspiration and appropriate antibiotic therapy with eradication of group C Neisseria meningitidis, pericardial effusion continued to reaccumulate. Institution of high-dosage corticosteroid therapy resulted in rapid resolution of the effusion. Only six other cases of primary meningococcal pericarditis have been reported in the English literature. Early manifestations of this disease are due to bacterial invasion of the pericardium. The later phase of intensive reaccumulation of sterile pericardial fluid may conceivably be related to meningococcal endotoxin and appears to be responsive to corticosteroid or salicylate therapy. Recognition of this phenomenon may obviate the necessity for a pericardiectomy.

Current evidence leaves little doubt that genital herpes is primarily a venereal disease. Like gonorrhea, it is frequently subclinical or asymptomatic. A high rate of infection is found among patients attending venereal disease clinics and among persons of low socioeconomic status. The infection (primary or recurrent) is generally self-limiting, but in a pregnant woman it poses a significant risk to the fetus. It also has been linked to an increased risk of cervical cancer. The Papanicolaou smear is a useful tool for early detection. Effective antiviral therapy for genital herpes is unavailable. Photodynamic inactivation appears promising in recurrent herpes but may be hazardous; malignant transformation of infected cells subjected to this process has been demonstrated in vitro.

In our earlier study, Neisseria gonorrhoeae was infrequently isolated while Bacteroides fragilis was totally absent from cul-de-sac aspirates of patients with acute pelvic inflammatory disease (PID). Twenty additional women were studied to further elucidate the bacteriology of this disease. Recovery rate of N. gonorrhoeae from cul-de-sac aspirates collected in selective transport medium (Transgrow) was 25 per cent among patients with gonococcal PID, compared to only 8 per cent when specimens were collected in a nonselective transport system (Anaport). In vitro studies confirmed a detrimental effect of the Anaport for survival of N. gonorrhoeae during transport. This suboptimal survival was primarily related to low pH of the transport system under prereduced conditions, and could be corrected when pH of the transport vial was preadjusted and maintained between 6 and 7. B. fragilis was again absent from the cul-de-sac in all patients, while streptococci, peptococci, and peptostreptococci remained the most predominant isolates. These data may explain the empiric observations that penicillin and tetracycline are effective in most cases of acute PID.

The prevalence rate of vaginal colonization with E. coli was studied prospectively among 495 healthy premenopausal women, and factors associated with vaginal carriage of E. coli were examined. Vaginal colonization with E. coli was found in 12% of women, and was significantly correlated with phase of the menstrual cycle (p less than 0.05), prior use of antibiotics (p less than 0.05), current genital complaints (p less than 0.05), history of previous urinary tract infection (p less than 0.001), and use of diaphragm or cervical cap for contraception (p less than 0.005). The high prevalence rate among diaphragm or cervical cap users remained significant when other confounding factors were kept constant (p less than 0.05). This observation may explain the association of diaphragm use and urinary tract infection demonstrated in previous epidemiologic studies and confirmed in the present study (p less than 0.05).

The in vitro activity of mezlocillin, a new ureidopenicillin, against 377 obligate anaerobes from the female genital tract, was studied by an agar dilution technique. Mezlocillin demonstrated broad-spectrum activity against all genital obligate anaerobes, with a geometric mean minimum inhibitory concentration (MIC) of 4.2 microgram/ml, and inhibited 84% of B. fragilis and 99% of all isolates at 64 microgram of the antibiotic per milliliter. At readily attainable serum concentrations, mezlocillin inhibited significantly more isolates than cefoxitin (p less than 0.0005), ampicillin (p less than 0.0005), penicillin G (p less than 0.005), and clindamycin (p less than 0.025); its activity was comparable to that of carbenicillin and chloramphenicol. Mezlocillin was significantly more active than ampicillin (p less than 0.025), penicillin G (p less than 0.025), and clindamycin (p less than 0.05) against Bacteroides species other than B. fragilis and B. melaninogenicus.

Anaerobic infections are reviewed with emphasis on management. Most anaerobic pulmonary infections respond to penicillin G, even when Bacteroides fragilis (penicillin-resistant) is present. Clindamycin is suitable in penicillin-sensitive patients. Intraabdominal infections have a complex flora usually involving anaerobes, especially B. fragilis. It is desirable to use antimicrobial therapy to cover potential pathogens of all types. Surgical drainage and debridement are extremely important considerations. Anaerobic bacteria were found in 72% of 200 patients with female genital tract infections and were the exclusive isolates in 30%. Surgical therapy is primary, but antimicrobial and anticoagulant therapy are also important. A variety of soft-tissue infections involve anaerobes. Surgery is the major therapeutic approach. Anaerobic endocarditis is uncommon but may be difficult to manage. Chloramphenicol is ordinarily the drug of choice for brain abscess. New antimicrobial agents, which are under investigation and are promising, include new penicillins, new cephalosporins, new tetracyclines, and metronidazole.

Diaryliodonium chemicals increased nitrogen (N) absorption, utilization of absorbed N and N retention in growing steers. Fifty parts per million of the chemicals (diphenyliodonium chloride, diphenyliodonium bromide, 4,4'-difluorodiphenyliodonium chloride or 4,4'-dimethyldiphenyliodonium chloride) in the diet appeared sufficient to promote significant (P less than .05 or .10) improvements in N utilization. Diet digestibility was either not affected or improved slightly. We suggest that diaryliodonium chemicals improve N utilization by adjusting the ruminal degradation of dietary protein to yield more amino-N and less ammonia-N.

Endocarditis due to Listeria monocytogenes is rare with only 13 cases cited in the world's literature. We report an additional case with a review of the previously reported patients. In contrast to other clinical forms of listeriosis, endocarditis does not tend to occur in patients with severe underlying disorders or those on immunosuppressive regimens. Listeric endocarditis has a predilection for left-sided cardiac involvement (100 percent), and systemic embolization is a major clinical feature (58 percent). Prognosis of listeric endocarditis is unfavorable and the mortality rate (43 percent) exceeds that for bacterial endocarditis with more common pathogens (23 percent). Antibiotic sensitivity data suggest that ampicillin or penicillin may be the chemotherapeutic agents of choice.

The rate of vaginal colonization with Escherichia coli in 495 healthy women was 12% in a prospective study with use of selective media and semiquantitative culture techniques. Computer-assisted multivariate analysis revealed that vaginal E. coli was significantly associated with the menstrual phase of the cycle, prior use of antibiotics, use of diaphragm or cervical cap for contraception, history of previous urinary tract infection, and coisolation of Staphylococcus aureus that was positive for the toxic shock syndrome toxin-1 (p less than 0.05, multiple stepwise logistic regression analysis). No significant association was observed with tampon use or brand, other contraceptive methods, sexual activity, genital symptoms, recent vaginal infection, or other personal habits. Quantitative cultures obtained sequentially throughout the menstrual cycle in 12 unselected women confirmed higher E. coli counts in menstrual or midcycle samples compared to paired premenstrual specimens (p less than 0.05, Wilcoxon paired rank sign test). These data emphasize the hormonal and other host determinants in vaginal colonization by E. coli and may explain the high rate of vaginal E. coli (64%), in addition to toxicogenic S. aureus, in acute toxic shock syndrome and the higher incidence of urinary tract infection in women with diaphragm or cervical cap for contraception compared to other contraceptive methods.

A drug usage audit of cefamandole was conducted at a 900-bed teaching hospital. Health records of all in-patients receiving cefamandole during a three-month period (November 1, 1985 to January 31, 1986) were retrospectively reviewed. Treatment of lower respiratory tract infections accounted for 35 (44%) of the 79 treatment courses examined. Surgical antimicrobial prophylaxis for cardiovascular procedures involved 26 (33%) courses of therapy and 15 (19%) courses were associated with biliary tract procedures. The three remaining treatment courses (4%) included therapy for septicemia, orthopedic surgery prophylaxis, and a leg ulcer. Twenty-eight percent of all treatment courses were deemed to be appropriate. Thirty-two percent were considered controversial, and 40 percent inappropriate. The majority of the suboptimal use identified involved prescribing cefamandole for cardiovascular surgery prophylaxis. The role of cefamandole in the acute hospital setting is reviewed with reference to other available first, second and third-generation cephalosporins. General recommendations for its use are outlined.

The susceptibility of 28 clinical isolates of Pseudomonas maltophilia to 16 antimicrobial agents was determined in vitro by a standard agar dilution method with inoculum sizes of 10(4) and 10(6) CFU. All isolates exhibited multiple drug resistance. Nine isolates were selected for studies of combinations of ciprofloxacin with seven antipseudomonal beta-lactams and three aminoglycosides by a checkerboard agar dilution technique. Synergistic or additive combinations of ciprofloxacin in clinically achievable concentrations were most frequent with mezlocillin (89%), followed by cefoperazone (67%), piperacillin (56%), cefsulodin (56%), and ceftazidime (33%), and were infrequent with aztreonam (11%), the aminoglycosides (0 to 14%), or imipenem (0%). Antagonism was not observed in any combination. These data suggest that combinations of ciprofloxacin with these agents may be useful for some nosocomial multiply drug-resistant P. maltophilia infections.

The hemolytic activity of 32 vaginal isolates of Staphylococcus aureus from patients with typical toxic shock syndrome (TSS) was contrasted with that of 50 vaginal isolates from patients without TSS, using a standardized inoculum (10(5) CFU) on 5% sheep blood agar after 48 h of incubation under 30% CO2. Additionally, 7 nongenital isolates from patients with nonmenstrual TSS and 57 strains of nongenital control isolates were included for comparison. Vaginal TSS strains were significantly less hemolytic than non-TSS S. aureus strains of either genital (P less than 0.001) or nongenital (P less than 0.01) origin. Vaginal TSS S. aureus strains were also less hemolytic than were nongenital TSS S. aureus strains (P less than 0.02). This reduced hemolytic activity of genital TSS S. aureus strains may provide a useful marker for screening and further delineation of toxigenic S. aureus associated with menstrually related TSS.

Gardnerella vaginalis has a very thin cell wall with a characteristic gram-negative staining pattern and an apparent lamellar structure when viewed at an oblique angle by electronmicroscopy. Examination at right angles to the cell-wall plane and by freeze-etching showed absence of an outer membrane or any other lamellar structure. Cell-wall extracts made by methods specific for lipopolysaccharide (LPS) gave negative reactions by silver staining and for endotoxin in the limulus amoebocyte lysate assay. 2-Keto-3-deoxy-D-manno-2-octonoic acid (KDO), heptose and hydroxy fatty acids specific for LPS were not detected in the extracts. G. vaginalis cell walls are unequivocally gram-positive in their ultrastructural characteristics and chemical composition.

In vitro susceptibility of 11 recent clinical isolates of Campylobacter fetus to 22 antimicrobial agents was determined by an agar dilution technique. Unlike most obligate anaerobic gram-negative bacilli, C. fetus isolates tested were relatively resistant to penicillin and cephalosporins, but exquisitely susceptible to tetracyclines and aminoglycosides. All strains were also inhibited at concentrations achievable in serum by clindamycin, chloramphenicol, metronidazole, carbenicillin, ticarcillin, and with rare exceptions, ampicillin. They were variably susceptible to lincomycin and erythromycin and highly resistant to vancomycin.