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Ksp-cadherin (cadherin-16) is an atypical member of the cadherin superfamily of cell adhesion molecules that is ubiquitously expressed on the basolateral membrane of epithelial cells lining the nephron and the collecting system of the mammalian kidney. The principal aim of the present study was to determine if Ksp-cadherin played a critical role in the development and maintenance of the adult mammalian kidney by generating and evaluating a mouse line deficient in Ksp-cadherin. Ksp-null mutant animals were viable and fertile, and kidneys from both neonates and adults showed no evidence of structural abnormalities. Immunolocalization and Western blot analyses of Na + -K + -ATPase and E-cadherin indicated that Ksp-cadherin is not essential for either the genesis or maintenance of the polarized tubular epithelial phenotype. Moreover, E-cadherin expression was not altered to compensate for Ksp-cadherin loss. Plasma electrolytes, total CO 2 , blood urea nitrogen, and creatinine levels were also unaffected by Ksp-cadherin deficiency. However, a subtle but significant developmental delay in the ability to maximally concentrate urine was detected in Ksp-null mice. Expression analysis of the principal proteins involved in the generation of the corticomedullary osmotic gradient and the resultant movement of water identified misexpression of aquaporin-2 in the inner medullary collecting duct as the possible cause for the inability of young adult Ksp-cadherin-deficient animals to maximally concentrate their urine. In conclusion, Ksp-cadherin is not required for normal kidney development, but its absence leads to a developmental delay in maximal urinary concentrating ability. NEW & NOTEWORTHY Ksp-cadherin (cadherin-16) is an atypical member of the cadherin superfamily of cell adhesion molecules that is ubiquitously expressed on the basolateral membrane of epithelial cells lining the nephron and the collecting system. Using knockout mice, we found that Ksp-cadherin is in fact not required for kidney development despite its high and specific expression along the nephron. However, its absence leads to a developmental delay in maximal urinary concentrating ability.

Medical treatment alone is rarely successful in left-sided infective endocarditis caused by Pseudomonas aeruginosa. We report the cure of such a case with high-dose meropenem in combination with tobramycin.

We have previously reported pilot data regarding the safety of saving partially used syringes of a glutaraldehyde cross-linked collagen for use in subsequent treatment sessions with the same individual. That single institution study involved 56 partially used syringes cultured for aerobic bacteria. Only one weakly positive culture was detected among these 56 samples, which prompted us to carry out this expanded study involving multiple centers and different injection techniques. Samples were collected from four centers. Following periurethral injection in an office setting, 166 partially used syringes of glutaraldehyde cross-linked collagen were refrigerated for between 1 and 104 weeks (average 58). Material from all 166 syringes was then cultured qualitatively and quantitatively for both aerobic and anaerobic organisms. Collagen from one syringe grew >100,000 colonies of Escherichia coli. All other cultures were negative. In the pilot study, one culture of 56 syringes was weakly positive for coagulase-negative staphylococcus. When the results from both studies were considered together, only two of 222 partially used syringes (0.9%) were contaminated. The background risk of local infection associated with periurethral collagen injection is approximately 0.29%. Using the statistical equation 'number needed to harm', we found that a clinician would have to reuse 111 syringes at a saving of $34,965 before he or she would cause a single local injection by so doing. Therefore, we feel that it may be cost-effective and safe to reinject material from a partially used syringe of glutaraldehyde cross-linked collagen during a subsequent treatment session on an individual.

The laboratory diagnosis of CNS infection is essential for optimal therapy. Acute infection requires rapid turn-around testing with high predictive values, that is, the ability of a test to accurately identify those patients who do or do not have disease caused by a specific etiology. The Gram's stain, fungal stains of direct smears, antigen testing for C. neoformans, and culture of bacteria, fungi, mycobacteria, and some viruses are important tests for the diagnosis of acute infection. The laboratory diagnosis of chronic infection necessitates discussion between the clinician and laboratory technician to allow triaging of testing. Antigen tests for bacteria, fungi, and viruses; antibody tests for multiple microorganisms; and PCR testing for bacteria, M. tuberculosis, and many viruses are all important in limited clinical situations. All testing for acute or chronic disease depends on sufficient specimen that is transported to the laboratory in a manner that will not compromise viability or chemical integrity. Sterile containers that maintain moisture content, exclude oxygen for anaerobic requests, and are stored at proper temperatures (22 degrees C room, 4 degrees C refrigeration, or -20 degrees C freezer depending on pathogen and test) are mandatory. Many laboratory issues addressing the diagnosis of CNS infection are changing or evolving. Most important is the recognition that bacterial antigen testing for the diagnosis of acute bacterial meningitis rarely impacts patient management and is not routinely needed, CSF shunt infections differ from usual meningeal infections and require rapid diagnosis, and TB meningitis remains a difficult disease to diagnosis but may be confirmed first by PCR testing of CSF. In addition, Whipple's disease of the CNS can be confirmed using PCR with CSF; CJD has a marker protein, referred to as 14-3-3 antigen, that can be detected in CSF, and the diagnosis of fungal CNS disease requires careful interpretation of direct smears, antigen and antibody testing, and culture. Most difficult to diagnose among the CNS infections are viral meningitis and encephalitis. The appearance of new etiologies, such as West Nile virus, and the common use of PCR for the herpes viruses and enteroviruses represent important advances. Evolving methods for the laboratory diagnosis of CNS infection represent significant improvements over previous testing; however, the array of tests available demands more attention for appropriate selection, is significantly more expensive, and requires new skills for performance and interpretation. The responsibility for proper use of laboratory testing lies both with the clinician and laboratory technician.

A key function of the proximal tubule is retrieval of most of the vast quantities of NaCl and water filtered by the kidney. Physiological studies using brush border vesicles and perfused tubules have indicated that a major fraction of Cl(-) reabsorption across the apical membrane of proximal tubule cells occurs via Cl(-)-formate exchange. The molecular identity of the transporter responsible for renal brush border Cl(-)-formate exchange has yet to be elucidated. As a strategy to identify one or more anion exchangers responsible for mediating Cl(-) reabsorption in the proximal tubule, we screened the expressed sequence tag database for homologs of pendrin, a transporter previously shown to mediate Cl(-)-formate exchange. We now report the cDNA cloning of CFEX, a mouse pendrin homolog with expression in the kidney by Northern analysis. Sequence analysis indicated that CFEX very likely represents the mouse ortholog of human SLC26A6. Immunolocalization studies detected expression of CFEX, but not pendrin, on the brush border membrane of proximal tubule cells. Functional expression studies in Xenopus oocytes demonstrated that CFEX mediates Cl(-)-formate exchange. Taken together, these observations identify CFEX as a prime candidate to mediate Cl(-)-formate exchange in the proximal tubule and thereby to contribute importantly to renal NaCl reabsorption. Given its wide tissue distribution, CFEX also may contribute to transcellular Cl(-) transport in additional epithelia such as the pancreas and contribute to transmembrane Cl(-) transport in nonepithelial tissues such as the heart.

Modern medicine has led to dramatic changes in infectious diseases practice. Vaccination and antibiotic therapy have benefited millions of persons. However, constrained resources now threaten our ability to adequately manage threats of infectious diseases by placing clinical microbiology services and expertise distant from the patient and their infectious diseases physician. Continuing in such a direction threatens quality of laboratory results, timeliness of diagnosis, appropriateness of treatment, effective communication, reduction of health care-associated infections, advances in infectious diseases practice, and training of future practitioners. Microbiology laboratories are the first lines of defense for detection of new antibiotic resistance, outbreaks of foodborne infection, and a possible bioterrorism event. Maintaining high-quality clinical microbiology laboratories on the site of the institution that they serve is the current best approach for managing today's problems of emerging infectious diseases and antimicrobial agent resistance by providing good patient care outcomes that actually save money.

Purpose: We evaluated the safety of saving partially used syringes of glutaraldehyde cross-linked collagen for subsequent treatment sessions in an individual., Materials and Methods: After periurethral injection in an office setting 56 partially used syringes of glutaraldehyde cross-linked collagen were stored in a refrigerator for 1 to 61 weeks (mean 15). Collagen from all 56 syringes was then cultured qualitatively using a broth medium at 35C and semiquantitatively using a chocolate agar plate at 22 to 30C for 5 days each., Results: A qualitative broth culture was positive for coagulase negative staphylococcus but the results of semiquantitative chocolate agar culture of material from the same syringe were negative. All cultures of the other 55 syringes were negative., Conclusions: The positive culture most likely resulted from contamination during periurethral injection or the culturing process. Minimal contamination from and the great potential cost savings of reusing glutaraldehyde cross-linked collagen for subsequent treatments in an individual indicate the need for an expanded study involving multiple centers.

To validate the accuracy of rapid tests for identification of Escherichia coli, five laboratories sequentially collected 1,064 fresh, clinically significant strains with core criteria of indole-positive, oxidase-negative, nonspreading organisms on sheep blood agar plates (BAP), having typical gram-negative rod plate morphology, defined as good growth on gram-negative rod-selective media. An algorithm using beta-hemolysis on BAP, lactose reaction on eosin-methylene blue or MacConkey agar, L-pyrrolidonyl-beta-naphthylamide (PYR), and 4-methylumbelliferyl-beta-D-glucuronide (MUG) was evaluated. Identifications using the algorithm were compared to those obtained using commercial kit system identifications. One thousand strains were E. coli and 64 were not E. coli by kit identifications, which were supplemented with conventional biochemical testing of low probability profiles. Of the 1,064 isolates meeting the core criteria, 294 were beta-hemolytic and did not require further testing to be identified as E. coli. None of the 64 non-E. coli strains were hemolytic, although other indole-positive, lactose-negative species were found to be hemolytic when further strains were examined in a follow-up study. Of the remaining strains, 628 were identified as E. coli by a lactose-positive and PYR-negative reaction. For nonhemolytic, lactose-negative E. coli, PYR was not helpful, but a positive MUG reaction identified 65 of 78 isolates as E. coli. The remaining 13 E. coli strains required kit identifications. This scheme for E. coli identification misidentified three non-E. coli strains as E. coli, for an error rate of 0.3%. A total of 13 kit identifications, 657 PYR tests, and 113 MUG tests were needed to identify 1,000 E. coli strains with the algorithm. The use of this rapid system saves laboratory resources, provides timely identifications, and yields rare misidentifications.

Our knowledge regarding the pathogenesis of infections relative to the oral cavity is rapidly expanding, similar to our overall understanding of how infectious diseases impact our daily lives. The complexity of the flora within the oral cavity is quite unique and often makes diagnosis difficult; however, it is becoming more apparent that accurate diagnostic testing is important from the standpoint of focusing appropriate therapy on pathogens within this crucial body site, and avoiding overuse of antimicrobial agents in settings of infection where they have no demonstrated benefit. New diagnostic methods are being developed to detect pathogens and rapidly delineate resistance patterns. Many will be based on new genetic assays, but they must be cost effective, sensitive, and specific. Another growing challenge is to provide adequate lab support to outpatient offices and clinics, without compromising the specimen culture or turnaround times. So many patients are being seen away from hospital laboratories that we need ways to diagnose sinusitis, pharyngitis, abscess, and other infections of the oral cavity without killing the anaerobes and other significant facultative bacteria, and without ruining the direct stains by overgrowth or inflammatory cell degradation during specimen transport. These results need to be available quickly enough to give useful information for office diagnosis in order to effect therapy. To optimize both diagnosis and treatment, a key to the future will be better communication between the clinical practitioner and laboratory, with an increasing emphasis on training expertise in medical microbiology and infectious diseases.

Kidney-specific cadherin (Ksp-cadherin, cadherin 16) is a novel, kidney-specific member of the cadherin superfamily that is expressed exclusively in the basolateral membrane of renal tubular epithelial cells. To characterize the Ksp-cadherin gene promoter, a lambda bacteriophage clone containing 3.7 kb of the proximal 5' flanking region of the mouse Ksp-cadherin gene was isolated. The transcription initiation site was mapped by RNase protection assays and 5' rapid amplification of cDNA ends, and a 709-bp intron was identified within the 5' untranslated region. The proximal 5' flanking region was "TATA-less" but contained other consensus promoter elements including an initiator (Inr), GC boxes, and a CAAT box. Potential binding sites were identified for transcription factors that are involved in tissue-specific gene expression including activator protein-2 (AP-2), hepatocyte nuclear factor-3 (HNF-3), basic helix-loop-helix (bHLH) proteins, CCAAT/enhancer-binding protein (C/EBP), and GATA factors. Transfection of luciferase reporter plasmids containing 2.6 kb of the 5' flanking region markedly increased luciferase activity in renal epithelial cells (MDCK and mIMCD-3) but not in mesenchymal cells (NIH 3T3 and MMR1). Deletion analysis identified an 82-bp region from -31 to -113 that was essential for promoter activity in transfected renal epithelial cells. Electrophoretic mobility-shift assays showed that mIMCD-3 cells contain nuclear proteins that bind to this region of the promoter. Mutational analysis showed that sequences within the HNF-3 consensus site and CAAT box were involved in protein binding and promoter activity. We conclude that the proximal 5' flanking region of the mouse Ksp-cadherin gene contains an orientation-dependent promoter that is kidney epithelial cell specific. The region of the promoter from -113 to -31 is required for transcriptional activity and contains binding sites for nuclear proteins that are specifically expressed in renal epithelial cells.

Kidney-specific cadherin (Ksp-cadherin, cadherin 16) is a tissue-specific member of the cadherin superfamily that is expressed exclusively in the basolateral membrane of tubular epithelial cells in the kidney. To determine the basis for tissue-specific expression of Ksp-cadherin in vivo, we evaluated the activity of the promoter in transgenic mice. Transgenic mice containing 3.3 kb of the mouse Ksp-cadherin promoter and an Escherichia coli lacZ reporter gene were generated by pronuclear microinjection. Assays of beta-galactosidase enzyme activity showed that the transgene was expressed exclusively in the kidney in both adult and developing mice. Within the kidney, the transgene was expressed in a subset of renal tubular epithelial cells that endogenously expressed Ksp-cadherin and that were identified as collecting ducts by colabeling with Dolichos biflorus agglutinin. In the developing metanephros, expression of the transgene in the branching ureteric bud correlated with the developmental expression of Ksp-cadherin. Identical patterns of expression were observed in multiple founder mice, indicating that kidney specificity was independent of transgene integration site. However, heterocellular expression was observed consistent with repeat-induced gene silencing. We conclude that the Ksp-cadherin gene promoter directs kidney-specific expression in vivo. Regulatory elements that are sufficient to recapitulate the tissue- and differentiation-specific expression of Ksp-cadherin in the renal collecting duct are located within 3.3 kb upstream to the transcriptional start site.

The potential for Ksp-cadherin involvement in either the development or maintenance of the metanephric kidney was assessed by immunocytochemical localization of a monoclonal antibody directed against the rabbit isoform of Ksp-cadherin in both neonatal and adult rabbit kidneys. In the adult kidney Ksp-cadherin expression was detected on the basolateral membrane of all cell types in both the tubular nephron and the collecting system. Immunoelectron microscopy indicated that Ksp-cadherin was expressed at uniform levels along the entire length of both the lateral membranes and the basal infoldings of all tubular epithelial cell types. In the nephrogenic zone of the neonatal rabbit kidney Ksp-cadherin expression was detected exclusively on the basolateral membranes of epithelial cells in the more highly differentiated regions of the expanding ureteric duct. In the highly differentiated corticomedullary and medullary regions of the neonatal kidney, distinct basolateral staining was observed in all segments of the tubular nephron and the collecting system. The relatively late appearance of Ksp-cadherin expression in the developing metanephros indicates that Ksp-cadherin probably does not participate in the direction of renal morphogenesis. However, the high levels of Ksp-cadherin expression observed in all segments of the tubular nephron and the collecting system in the adult kidney suggests that it may play a role in the maintenance of the terminally differentiated tubular epithelial phenotype.

The laboratory diagnosis of infections of the respiratory tract is not an exact science, with many clinicians electing to empirically select antimicrobial therapy without the benefit of laboratory testing. With trained laboratory personnel and the proper selection of tests, accurate laboratory diagnosis is available. Progress is occurring most rapidly with molecular methods, such as polymerase chain reaction (PCR) testing. As molecular approaches are technically simplified and become less expensive, advances in the laboratory diagnosis of most respiratory tract infections caused by fastidious pathogens will occur. The diagnosis of non-fastidious bacteria, that require in-vitro antimicrobial testing, will continue to require conventional culture methods. New bronchoscopic methods, quantitative evaluation of cultures, and recognition of intracellular bacteria in stained smears do improve the usefulness of conventional culture and stain in the diagnosis of pneumonia.

Ksp-cadherin is a novel kidney-specific member of the cadherin superfamily of cell adhesion molecules. We have determined the complete cDNA coding sequences of both the human and the mouse isoforms of Ksp-cadherin. The inferred amino acid sequences of the human and mouse isoforms are 79 and 75% identical to the originally described rabbit isoform of Ksp-cadherin (Thomson et al., 1995; J. Biol. Chem. 270, 17594-17601), respectively. The relative locations of cadherin-specific sequence motifs, putative N-glycosylation sites, and characteristic protein domains are entirely conserved in all three isoforms. Multiple organ Northern analyses indicate that, as in the rabbit, both the human and the mouse Ksp-cadherin transcripts appear to have distinct kidney-specific distributions. The human Ksp-cadherin gene (CDH16) maps to chromosome 16q21-proximal 16q22. The mouse Ksp-cadherin gene (Cdh16) was localized to a highly syntenic region of distal Chromosome 8. Both the human and the mouse Ksp-cadherin genes were localized to previously identified clusters of cadherin gene sequences, consistent with the hypothesis that most cadherin family members arose by gene duplication from a single ancestral gene at a relatively early stage in the evolution of the mammalian genome., (Copyright 1998 Academic Press.)

The proper use and interpretation of clinical microbiology test results may be complicated but critical to the care of cancer patients. The microbiology laboratory director is often available to offer advice concerning the differential diagnosis, choice of specimens, as well as the optimal stains and cultures to facilitate diagnosis. Additionally, the rapid interpretation of Gram-stained smears provides useful, occasionally lifesaving, information relative to the etiologic diagnosis and empiric antimicrobial therapy. The microbiology laboratory director should also provide further interpretation of culture and antimicrobial testing results that allow the clinical service to focus on the most critical data. Person-to-person or telephone conversations discussing important laboratory information should be followed up by a written summary report placed in the patient's chart so all services involved share the same interpretation (Figure 2). The clinical service has an important responsibility to communicate with the laboratory to optimize care of the patient with cancer. The laboratory compiles data collected from groups of patients that is available and useful to physicians. Review and discussion of test utilization is essential for cost-effective, quality health care. This may include analysis of blood cultures documenting an acceptable level of contamination, appropriate number collected per day, and sufficient blood volume per culture. In addition, information about changing resistance patterns or nosocomial transmission can be provided to the clinician. As patients with malignancies become more complex and their infections increasingly difficult to treat, regular interaction between the laboratory and clinician is likely to improve patient care.

Health care reform has provided clinical microbiology laboratory directors with new responsibilities and challenges that should highlight and enhance their importance within the health care system. Results of a survey sent to directors suggest that management tasks have increased since 1990, and activities that move the director into the hospital and patient care environment underscore their value to the health care team. These activities include participation on clinical practice guidelines pathway committees and use of consultative and interpretative reports. Survey results also summarize the directors' qualifications, laboratory size, typical daily schedule, job responsibilities, hours worked, time away from the laboratory for professional purposes, and comments about one's most important functions. In summary, failure to recognize new responsibilities could result in the disappearance of the position of director as we know it. Capitalizing on this challenge will secure the microbiology director's role for decades to come.

The BACTEC 9240 blood culture system (Becton Dickinson Diagnostic Instrument Systems, Sparks, Md.) is one of three automated, continuous-monitoring systems that is widely used in clinical laboratories. The BACTEC 9240 was compared with the BACTEC NR 660 for the detection of organisms and bacteremic episodes; time to detection of positive cultures; number of false-positive and false-negative cultures; and time needed to load, process, and perform quality control functions by using high-volume aerobic media. Blood specimens (5,282) were inoculated in equal volumes (5 to 10 ml per bottle) into BACTEC Plus Aerobic/F (9240 system) and BACTEC Plus NR26 (660 system) bottles. Clinically significant isolates were detected in 6.6% of cultures, representing 348 microorganisms and 216 bacteremic episodes. Two hundred forty-eight microorganisms were detected by both systems, 48 by the 9240 only and 52 by the 660 only (P = not significant). Of the bacteremic episodes, 158 were detected by both systems, 27 by the 9240 only and 31 by the 660 only (P = not significant). Analysis of data by month revealed equivalent recovery rates for both systems, with the exception of a 30-day period at one study site during which the 660 system detected significantly more microorganisms. Following a proprietary hardware design retrofit of the 9240 instrument, detection rates were again equivalent for the remaining three months at this study site. Positive cultures detected by both systems were detected an average of 4.3 h faster by the 9240 system (21 versus 25.3 h). The numbers of false-positive cultures for the 9240 and 660 systems were 40 (1.0%) and 9 ( < 1.0%), respectively. The numbers of false-negative cultures were five for the 9240 system and three for the 660 system. The 9240 system required 23 s less technologist time per bottle to operate during the 5-day protocol. In conclusion, the BACTEC 9240 used with high-volume Aerobic/F medium is equivalent to the BACTEC 660 used with high volume NR26 medium for the detection of microorganisms and bacteremic episodes. In addition, the 9240 system detects positive cultures more rapidly than the 660 system but requires further evaluation to ensure reliability of instrument components.

Cadherins are recognized as the principal mediators of homotypic cellular recognition and play a demonstrated role in the morphogenic direction of tissue development. We report here the identification of a structurally unique, kidney-specific member of the cadherin multigene family (Ksp-cadherin). cDNA cloning and molecular analysis of the 130-kDa protein confirmed that it was novel and indicated that it most closely resembled members of the LI-cadherin/HPT-1 cadherin subgroup. The predicted protein possesses the definitive cadherin-specific sequence motifs LDRE, DXND, and DXD in well conserved sequential arrangement, and the characteristic cysteine residues found in the last ectodomains of almost all known cadherins. Like LI-cadherin and HPT-1, Ksp-cadherin lacks the prosequence and HAV adhesion recognition sequence typical of most classical cadherins, and possesses a truncated cytoplasmic domain (18-22 amino acids). When expressed in a transient Vaccinia/T7 expression system, Ksp-cadherin displayed the classic calcium sensitivity to trypsin proteolysis that is observed in all cadherins. Immunolocalization studies and Northern analysis indicated that expression of Ksp-cadherin was kidney-specific and limited to the basolateral membranes of renal tubular epithelial cells. In summary, we have identified and cloned a novel, kidney-specific member of the cadherin multigene family that we propose be designated Ksp-cadherin.

An outbreak of ventilator-associated Pseudomonas aeruginosa respiratory infections in an intensive care unit of a teaching hospital was found to be associated with contaminated food coloring dye. Serotyping and bacteriocin typing indicated that the same strain of Pseudomonas was isolated from the food dye and from the respiratory cultures of the majority of patients. This observation lends credence to the importance of gastric colonization preceding pneumonia in ventilated patients.

The value added by acute-care hospitals is in the form of specific procedures (therapy, operations, testing) and the bed care necessary to make the procedures effective. When more than one hospital exists in a local area (defined in many studies as a radius of 15 mi/24 km) they compete for market share, since greater market share has a positive effect on economies of scale, utilization rates, learning curves and levels of quality. Competition is not only with other hospitals (and 75% of all hospitals do have a competitor within 24 km), but also with doctors who now perform some procedures in their offices, and with specialized clinics. The first strategy is to attract physician allegiance since they act as gate-keepers, directing patients to specific hospitals. This is done through personal amenities, professional amenities and enhancement to personal prestige and income. This competition for physician allegiance has a direct effect on utilization rates (doctors want spare capacity to suit their needs), on the range of services and facilities offered (doctors want more support), and on length of stay (doctors want longer stays). All of these increase the hospital's costs. The second strategy is to enter into contracts with third-party payers who will direct their clients to specific or preferred hospitals. The negative effect is that in competitive markets such payers may be able to bargain prices down. However, hospital differentiation makes it difficult for payers to make complete substitutions among them. As well, since the payers compete for clients, they often use hospital alliances as a selling point and therefore are often cooperative rather than confrontational in their negotiations. One tactic used by hospitals is to stress quality of service. But since quality in health care is hard to measure, patients are often unable to make direct assessments of alternatives. Hospitals therefore often 'signal' quality in various ways which may, and often do, increase hospital costs. (Some of these signals also attract physicians). Price is not a major element in competition. Most other strategies and tactics raise hospital costs and therefore price. Pressure from payers is turned back through differentiation (preventing substitution) and hospital-payer alliances for clients. Health care comes in too many packages to allow effective price competition. A final tactic is to increase the range of services or facilities offered. Enhanced services attract doctors by offering more support; attract some patients direct; and help to recapture market share lost to specialized clinics.(ABSTRACT TRUNCATED AT 400 WORDS)

Treatment of serious infections caused by gram-negative bacilli with beta-lactam antimicrobial agents can induce Class I beta-lactamase production. This phenomenon can result in resistant microorganisms, and has been postulated to be a cause of therapeutic failure. The charts of patients bacteremic with Pseudomonas aeruginosa, Serratia marcescens, Enterobacter cloacae, Citrobacter freundii, Proteus vulgaris, and Providencia species (n = 120) during a 3-year period were reviewed to determine how common the emergence of resistance was, and to determine if in vitro susceptibility testing was a reliable therapeutic guide. Emergence of resistance was believed to occur when a subsequent bacteremic isolate showed at least a fourfold increase in minimum inhibitory concentration accompanied by a change of interpretive susceptibility category. In the group of patients who survived at least 48 hours that received beta-lactam therapy (n = 76), one case of emergence of resistance was identified (1.3%). Emergence of resistance to beta-lactam antimicrobial agents did not commonly cause therapeutic failure at our institution, and susceptibility testing of gram-negative bacilli by usual methods was a reliable guide to antimicrobial therapy.

Study Objectives: To characterize the clinical presentation and identify factors predictive of bacteremia in elderly patients., Design: Retrospective review of emergency department charts, hospital records, and microbiology reports., Setting: Community teaching hospital with annual ED census of 65,000 adults., Participants: Seven hundred fifty elderly patients (aged 65 to 99 years) who were evaluated by the emergency physician, had blood cultures obtained in the ED, and were hospitalized with a suspected infectious process during a 12-month period., Measurements: Records were analyzed for demographic information, underlying diseases, clinical presentation, laboratory findings, sources of infection, and causative organisms. Using contingency tables, 79 patients with positive blood cultures were compared with a random sample of 136 patients with sterile blood cultures to identify clinical variables significantly (P less than .05) associated with bacteremia. Logistic regression analysis was performed with significant factors to develop a model to predict bacteremia. Sensitivity, specificity, and predictive values were calculated for the model., Main Results: The prevalence of bacteremia was 10.6%. Escherichia coli was the most commonly isolated pathogen (29% of cases), and the urinary tract was the most common source of infection (44.3% of cases). Logistic regression analysis showed that altered mental status (odds ratio, 2.88; 95% confidence interval [Cl], 1.52 to 5.50), vomiting (odds ratio, 2.63; 95% Cl, 1.16 to 6.15), and WBC band forms of more than 6% (0.06) (odds ratio, 3.50; 95% Cl, 1.58 to 5.27) were independent predictors of bacteremia. The presence of at least one of these three factors had a sensitivity of 0.85 (95% Cl, 0.75 to 0.92) and a specificity of 0.46 (95% Cl, 0.38 to 0.55) for predicting bacteremia in the study group. The positive predictive value was 0.16 (95% Cl, 0.12 to 0.19) and the negative predictive value was 0.96 (95% Cl, 0.94 to 0.98) for the ED patient group that met inclusion criteria., Conclusion: Elderly patients fail to manifest identifiable clinical features indicative of bloodstream infection. The sensitivity and specificity of the best statistical model for identifying bacteremic elderly patients suggest that clinical indicators alone are unreliable predictors of bacteremia in the geriatric ED population studied.

Infections in pregnancy with Ureaplasma urealyticum have been associated with a wide range of adverse outcomes, such as early abortion, stillbirth, prematurity, and neonatal morbidity and mortality. Causality has been difficult to demonstrate secondary to the high prevalence of asymptomatic lower genital tract (LGT) colonization and culture data from inaccessible or potentially contaminated sites. Between 1985 and 1989, 2461 second-trimester genetic amniocenteses were evaluated at the cytogenetics section of the Children's Hospital Medical Center of Akron. All were cultured for the genital mycoplasmas: Mycoplasma hominis and Ureaplasma urealyticum. A total of nine patients were positive, all for Ureaplasma urealyticum, with one patient excluded because of subsequent therapeutic abortion. In addition, complete follow-up data, such as indication for amniocentesis, serum alpha-fetoprotein levels, gestational age at parturition, and outcome of pregnancy, were available on 86 Ureaplasma-negative (U-) patients during an approximate 2-year span within the time-frame of the study. This was in part due to physician response to a questionnaire sent after amniocentesis. Of the eight positive cultures, 100 per cent were associated with an adverse outcome, defined as fetal loss or premature delivery. This was significant compared with the U- group (p less than 0.001) with a more than eight times greater risk of adverse outcome. Six (75 per cent) resulted in spontaneous miscarriage within 4 weeks of amniocentesis and at less than 21 weeks' gestation. Two (25 per cent) delivered prematurely, with one (12.5 per cent) neonatal death at 24+ weeks. Histological examination of all eight placentae and the seven fetuses revealed a 100 per cent incidence of chorioamnionitis and pneumonia, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

The cellular mechanisms responsible for rectal acidification in the desert locust, Schistocerca gregaria, were investigated in isolated recta mounted as flat sheets in modified Ussing chambers. Previous studies conducted in the nominal absence of exogenous CO2 and HCO3- suggested that the acidification was due to a proton-secretory rather than bicarbonate-reabsorptive mechanism (Thomson, R.B., Speight, J.D., Phillips, J.E. 1988. J. Insect Physiol. 34:829-837). This conclusion was confirmed in the present study by demonstrating that metabolic CO2 could not contribute sufficient HCO3- to the lumen to account for the rates of rectal acidification observed under the nominally CO2/HCO3(-)-free conditions used in these investigations. Rates of luminal acidification (JH+) were completely unaffected by changes in contraluminal pH, but could be progressively reduced (and eventually abolished) by imposition of either transepithelial pH gradients (lumen acid) or transepithelial electrical gradients (lumen positive). Under short-circuit current conditions, the bulk of JH+ was not dependent on Na+, K+, Cl-, Mg2+, or Ca2+ and was due to a primary electrogenic proton translocating mechanism located on the apical membrane. A small component (10-16%) of JH+ measured under these conditions could be attributed to an apical amiloride-inhibitable Na+/H+ exchange mechanism.

Clinical manifestations and radiographic findings are unreliable guides to the selection of antimicrobial therapy for lower respiratory infections. Laboratory evaluation is necessary to identify the etiologic agent. Multiple oral antibiotics are available for outpatient treatment of bronchitis or pneumonia suspected to be of bacterial origin.

Corynebacterium group D2 is a gram-positive bacillus easily identified in clinical microbiology laboratories. However, this organism is often disregarded as a skin and mucous contaminant. The Spanish literature has recently described Corynebacterium group D2 as a urinary pathogen in a specific patient population. We report a case of Corynebacterium group D2 infection to illustrate the potential pathogenicity and clinical presentation of infection due to this organism in the United States.

Acridine orange was used to stain smears of mouse lung which contained cyst and trophozoite forms of Pneumocystis carinii. Trophozoite forms stained yellow to orange; however, cyst forms did not stain. Acridine orange is a rapid and sensitive method for demonstrating trophozoites of P. carinii in mouse lung tissue.

The antimicrobial susceptibility of clinical isolates of the Bacteroides fragilis group was determined at six community hospitals (one large, greater than 600 beds; and five smaller, 96-325 beds). Imipenem was the most active beta-lactam with 100% of isolates being sensitive at 4 micrograms/ml. The percentage of isolates inhibited at 16 micrograms/ml (and 32 micrograms/ml) for the 7-alpha-methoxy antibiotics was: cefoxitin 66 (90); moxalactam 73 (85); cefotetan 68 (72); cefmetazole 40 (61). Metronidazole, chloramphenicol, and clindamycin were active against 100%, 100%, and 89% at breakpoints of 8 micrograms/ml, 8 micrograms/ml, and 4 micrograms/ml, respectively. The activity of several beta-lactams in our report differed slightly from that reported from university teaching hospitals. There were differences at many of the breakpoints for activity of some of the beta-lactam antibiotics for isolates from the large community hospital as compared with the combined isolates from the smaller community hospitals. Interestingly, the pattern was one of more resistance at the smaller community hospitals.

A case of botfly myiasis occurred in a patient who traveled to Brazil. This infestation resembles a pyogenic furuncle, but should be a diagnostic consideration when it does not respond to antibiotic therapy in a world traveler.

Acute vitamin D intoxication from an unknown source occurred in a family consisting of a grandmother, mother, father and four children aged 14, 11, 8 and 1 1/2 years old. The clinical presentation and response to treatment (which included a diphosphonate preparation and cholestyramine) are described.

Of 16 children with primary duodenal ulcer, 11 had complete relief of symptoms with initial full dose cimetidine therapy. After stopping cimetidine two of these 11 relapsed, six are in remission and three occasionally complain of abdominal pain requiring antacids. The remaining five children showed no improvement at all. Only one out of the 16 children showed side-effects due to cimetidine. Although there was wide variation in dosage of cimetidine and duration of therapy, no significant difference was noted in the dosage regimen of responders and non-responders to cimetidine. We suggest, full dose cimetidine 20 to 40 mg/Kg/day for 4 to 8 weeks, followed by 8 mg/Kg nocte daily for another 4 to 8 weeks.

The relationship between ammonia secretion (JAmm), hydrogen ion secretion (JH), and intracellular pH (pHi) was investigated in isolated locust (Schistocerca gregaria) rectal epithelia mounted as flat sheets in specially designed Ussing chambers. In the absence of exogenous CO2 and ammonia, the rectum is capable of net acid and ammonia secretion into the lumen against pH gradients of up to 1.8 U. JAmm was dependent on the presence of luminal amino acids and Na+ and it was relatively unaffected by K+ removal or changes in membrane potential. JAmm and pHi remained fairly constant over a luminal pH range of 7-5, whereas JH decreased linearly to zero over the same pH range. Mucosal addition of 1 mM amiloride reduced JAmm by 60%. This study demonstrates that the locust rectum secretes significant quantities of endogenously produced ammonia preferentially into the lumen as NH+4 rather than NH3. Moreover, the results suggest that the ammonia crosses the apical membrane via an amiloride-inhibitable Na+-NH+4 exchange mechanism.

The urinary excretion of the renal proximal tubular enzyme, gamma-glutamyltransferase (gamma-GT), has been studied in 41 patients receiving tobramycin, gentamicin or streptomycin for a variety of infections. All patients receiving tobramycin or gentamicin have shown increased excretion of gamma-GT in the urine. Only 46% of those receiving streptomycin have shown an increase in gamma-GT excretion and this is of a lesser degree. A change in creatinine clearance which could only be explained by antibiotic administration was detected in three patients (2 on gentamicin, 1 on streptomycin). The degree of elevation of urinary gamma-GT activity was greater when the initial creatinine clearance was lower, and it is therefore suggested that those patients with pre-existing renal dysfunction should be monitored particularly carefully for signs of nephrotoxicity from these antibiotics. Urinary gamma-GT is a useful enzyme in the investigation of renal drug effects.

A glucose-negative, maltose-positive strain of group C Neisseria meningitidis was isolated from the blood of a 63-year-old man. Interestingly, maltose degradation was detected by radiometric methods but not by growth methods.

The laboratory diagnosis of Pneumocystis carinii pneumonia in humans includes the identification of cysts in stained lung tissue impression smears. By using a mouse model, we compared the number of cysts in lung tissue impression smears with those contained in a concentrate of homogenized lung tissue. Eleven C3H/HEN mice developed P. carinii infection after corticosteroid injections, a low protein (8%) diet, and tetracycline administered in drinking water. Impression smears were prepared with freshly bisected lung tissue. Smears of concentrates were prepared with sediment from centrifuged lung tissue homogenates. All smears were made in duplicate, stained with toluidine blue O or methenamine silver, coded, randomized, and examined. The concentrate preparations contained more cysts per microscopic field than the impression preparations (P less than 0.01). Concentrates prepared by grinding with a mortar and pestle contained more cysts than concentrates prepared by blending with a Stomacher (P less than 0.05). Cysts were detected equally well with either the toluidine blue O or silver stain (not significant). Lung tissue concentrates were superior to lung tissue impressions for detecting P. carinii cysts in mice. Use of lung tissue concentrates should be considered for the diagnosis of human P. carinii infection.

One hundred and ninety six Asian, 89 African, 96 Chinese and 98 Scottish children from 173 families were studied to assess growth in relation to country of birth, time of parental residence in Scotland, child order in family, social class, living conditions and dietary factors. The growth measurements (standardised height, weight and bone age) differed between ethnic groups. The Africans were the tallest and Scottish the shortest. In all immigrant groups, children born in Scotland were on average, taller and more advanced in bone age than those born in their country of origin. In this study, there was no demonstrable effect on growth of social class or of living conditions. Dietary variable showed a lack of coherent effects on growth.

Duplicate antimicrobial susceptibility test results were reviewed over a 1-year period to determine whether repeat testing of sequential isolates with the same identification from the same patient and specimen site was necessary. In our institution, repeat testing is always needed for coagulase-negative staphylococci and Pseudomonas aeruginosa and is needed after 3 days for members of the family Enterobacteriaceae, but it is not routinely necessary for Staphylococcus aureus.

One hundred enuretic children were treated in closely supervised trial conditions with nine commonly used enuresis alarm systems available commercially in the United Kingdom. Although there was little difference between the systems in terms of their effectiveness in stopping bed wetting, parents preferred the Eastleigh and Urilarm De-Luxe models which had distinct advantages in respect of false alarms, breakdowns, and durability of pads. Enuresis alarms that perform poorly in these respects may lead to loss of enthusiasm and non-compliance. The systems vary widely in price, but a private buyer may find a cheaper alarm just as effective.

A blood culture was performed by adding a vented Septi-Chek bottle (Roche Diagnostics, Div. Hoffmann-LaRoche Inc., Nutley, N.J.) to a standard BACTEC system (Johnston Laboratories, Inc., Towson, Md.) blood culture. The yield of bacteremic patients, the clinical significance of organisms detected, and the cost of the combination system were compared with those of the standard BACTEC system alone. Each culture included 20 ml of blood divided among a BACTEC 6B aerobic bottle (5 ml), a BACTEC 7D anaerobic bottle (5 ml), and a Septi-Chek bottle equipped with a slide subculture attachment (10 ml). Significant isolates grew in 9.6% of the 2,269 cultures evaluated. The combination BACTEC plus Septi-Chek system detected 25% more bacteremic patients than the BACTEC system alone, 129 patients versus 103. The 26 bacteremic patients detected by only the added Septi-Chek bottle included 7 whose organism was isolated from blood alone and 19 whose organism was in mixed or pure culture from a second source. Detection of the organism resulted in alteration of antimicrobial therapy in 17 of these 26 patients. The combination system, which cultured a 20-ml blood volume, cost $11,000 more during the study period than the BACTEC system alone, which cultured a 10-ml volume. Reimbursement under the diagnosis-related group system was increased by $23,000 as a result of documentation of sepsis in these 26 patients. Blood volume and, possibly, the use of multiple blood culture systems are important factors when selecting a blood culture procedure for routine use.

A commercially available (Electro-Nucleonics, Inc.) indirect fluorescent antibody test was evaluated for the detection of cytomegalovirus-specific IgM antibody in serum of newborn infants. The serum IgM fraction from 13 symptomatic newborns with cytomegalovirus infection and 30 control infants was tested. Seven of 13 infected infants and none of 30 control infants had a positive IgM test. This cytomegalovirus-specific IgM test is rapid and specific but lacks sensitivity.

Overall contamination (on- plus off-streak) of the Isolator (Du Pont Co.) blood culture tube (23%) was greater than that of a conventional broth blood culture bottle (0.6%) or that of a biphasic blood culture bottle (1.3%). To determine the source of this contamination, Isolator cultures of blood from 59 healthy volunteers and of sterile broth from 60 vials were made. A total of 37% of the blood cultures and 22% of the broth cultures were contaminated (P = 0.06). Staphylococcus epidermidis-contaminated cultures represented 31 and 10% of the blood and broth cultures, respectively (P = 0.06). Contamination of plates processed on a bench top, in front of horizontal laminar flow, and in a biological safety cabinet with vertical laminar flow were compared. Processing plates in a biological safety cabinet resulted in a significant reduction in the number of contaminated plates (P less than 0.05). The contamination rate for 7,874 Isolator blood cultures processed in the biological safety cabinet was significantly decreased to 6.7% on-streak (9.3% on- plus off-streak). Contamination of Isolator-processed blood cultures originated from the laboratory and the patient. The former can be reduced by inoculating plates in a vertical laminar flow biological safety cabinet and by maintaining adequate quality control of media. The latter may be unavoidable.