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A 34-year-old male receiving chronic parenteral nutrition for treatment of short bowel syndrome and intermittent immunosuppressive agents for juvenile rheumatoid arthritis developed recurrent, catheter-associated Rhodotorula rubra fungemia over a one-year period. Infection with this yeast is associated with insertion of central venous catheters. Recurrence of R. rubra infection is an unusual event that presumably occurred because of chronic skin colonization by the organism.

Bacterial vaginosis (BV) in pregnancy is related to numerous adverse events; however, the validity of different methods of vaginal swab collection to diagnosis BV among pregnant women is unclear. This study examines the validity of self-collected compared with provider-collected vaginal swabs and describes the intra-rater and inter-rater reliability of BV assessment among a sample of pregnant women early in gestation. Gram-stain evaluation of vaginal samples using the Nugent criteria was conducted to determine the overall and morphotype-specific BV scores. We found strong validity for the overall and morphotype-specific scores comparing self-collected swabs to provider-collected swabs. In addition, we found excellent overall and morphotype-specific inter-rater reliability and excellent intra-rater reliability in our sample. These study results support the use of self-collected vaginal swabs for diagnosing BV and document the reliability of BV assessment among pregnant women.

Therapeutic options for vancomycin-resistant enterococcal (VRE) bloodstream infections are extremely limited. Chloramphenicol is effective when VRE isolates are susceptible to this agent. However, longitudinal trends in chloramphenicol-resistant VRE (CR-VRE) are unknown. The possible association between CR-VRE and antibiotic use has not been studied. We analyzed the antimicrobial susceptibility profiles of all VRE blood isolates from 1991-2000 at our institution. We performed a correlational study to examine the relationship between annual hospital-wide use of specific antibiotics and antibiotic classes and CR-VRE prevalence. During the 10-year study period, the prevalence of CR-VRE increased from 0 to 11% ( P< 0.001, trend). CR-VRE prevalence was correlated only with chloramphenicol use (P=0.05 ) and quinolone use (P= 0.01 ). If these trends continue, dependence on newer, more expensive agents will increase. The correlation between both chloramphenicol use and quinolone use and the prevalence of CR-VRE suggests that efforts to preserve the utility of chloramphenicol in VRE infections may depend on optimizing the use of these agents.

We evaluated the Vitek EPS card as a screen for the enteric pathogens Salmonella spp., Shigella spp., and Yersinia enterocolitica. Salmonella spp., Shigella spp., and Y. enterocolitica (125, 54, and 5 isolates, respectively) and 81 nonenteric pathogens that might be selected for screening from primary plates (non-lactose fermenters) were tested. The EPS card correctly identified 183 of 184 pathogens tested (sensitivity, 99.5%). Of 81 nonenteric pathogens screened with the EPS card, 8 were identified as possible enteric pathogens (specificity, 90.1%). We reviewed our stool culture records over the past 1.5 years and analyzed the specificities of TSI-urea screens for 300 stool cultures that had suspicious colonies. From 55 of 300 stool cultures, either Salmonella spp. or Shigella spp. were isolated, and from 245 stool cultures, no pathogen was isolated. Of the 245 negative cultures, 166 gave false-positive screening-test results that resulted in further biochemical identification procedures (Analytab Products or Vitek identification). Thus, the specificity of the TSI-urea screen in our experience was 32.2%. The Vitek EPS card was shown to be a more cost-effective screening procedure than the TSI-urea screen.

A healthy 23-year-old man with fever and a tender mass in his right anterior neck was found to have a branchial cleft cyst infected with Bordetella bronchiseptica . Initial testing suggested a Brucella species, but further laboratory testing identified the organism definitively. B. bronchiseptica infection in healthy adults is an unusual event.

Photodynamic therapy is a technique for killing cells with visible light after pretreatment with a photosensitizing agent. We demonstrated significant in vitro fungicidal activity against Aspergillus fumigatus of the photosensitizer Green 2W, activated with 630 nm light. This effect was both inoculum- and light dose-dependent. At a Green 2W concentration of 31.5 mg/L, there was complete killing of 2.7 x 10 1 cfu/mL with a light dose of 110 J/cm 2 and up to 2.7 x 10 6 cfu/mL with a light dose of 385 J/cm 2 .

Two rapid, single-use immunoassays for C. difficile toxin A, the Clearview C. DIFF A (Wampole Laboratories, Cranbury, N.J.) and the ImmunoCard Toxin A assays (Meridian Diagnostics Inc., Cincinnati, Ohio) were compared to the cytotoxin assay for their ability to detect C. difficile toxin in fecal specimens. A total of 537 specimens were tested and 47 (8.8%) were positive by the cytotoxin assay. The sensitivity, specificity, positive predictive value, and negative predictive value of the toxin A assays were as follows: 70.2% (95% CI, 57.1 to 83.3), 98.8% (95% CI, 97.8 to 99.8), 84.6% (95% CI, 73.3 to 95.9), and 97.2% (95% CI, 95.7 to 98.6) respectively for the Clearview assay; and 74.5% (95% CI, 62.0 to 86.9), 99.0% (95% CI, 98.1 to 99.9), 87.5% (95% CI, 77.3 to 97.8), and 97.6% (95% CI, 96.2 to 98.9) respectively for the ImmunoCard assay. Both toxin A assays are less sensitive than the cytotoxin assay, however, these assays offer a rapid and easy-to-perform test that may be used in conjunction with the cytotoxin assay for laboratory confirmation of C. difficile-associated disease.

The Agilent 2100 bioanalyzer (Agilent Technologies, Palo Alto, Calif.) utilizes capillary electrophoresis on a microchip device (LabChip 7500; Caliper Technologies, Mountain View, Calif.) that is capable of rapidly sizing small DNA fragments. To determine whether the system could replace conventional restriction fragment length polymorphism (RFLP) typing by agarose gel electrophoresis, we compared the analyzer with conventional flagellin RFLP for typing Campylobacter jejuni . Ninety-seven isolates representing 46 Fla types were initially analyzed. Correct Fla types were detected in 59% of the isolates. The major problem with the system was in resolving samples containing multiple DNA fragments differing from 8 to 20 bp. Overall, the bioanalyzer has the potential to replace conventional RFLP analysis by gel electrophoresis, but improvements in the chip separation are needed.

Niacin-positive Mycobacterium kansasii was isolated from three patients, two with respiratory infections and one with a perirectal abscess. The isolates were phenotypically similar to other strains of M. kansasii, differing only in their ability to produce niacin. This phenotype has been reported only twice in the literature, during the 1960s.

Intestinal immunoglobulin A (IgA) anti-campylobacter flagellin antibodies were measured by an enzyme-linked immunosorbent assay in patients with and without campylobacter infections. The level of fecal IgA antiflagellin antibodies was significantly higher in patients than in controls, but only 12 of 29 patients (41.4%) with a campylobacter infection had detectable IgA antibodies against flagellin (optical density, greater than or equal to 0.100). Further testing of fecal IgA antibodies from 10 patients with homologous and heterologous purified flagellins showed strain specificity in 1 patient. Cross-reactivity of fecal IgA antibodies with heterologous flagellins did not correlate with the Lior serotype of the isolate.

Infection with Campylobacter jejuni serotype HS:19 is associated with the development of Guillain-Barre syndrome (GBS). To determine whether a particular HS:19 clone is associated with GBS, multilocus enzyme electrophoresis (MLEE) was used to analyze a worldwide collection of isolates. There were 34 electropherotypes (ETs) in 3 phylogenetic clusters among 83 C. jejuni isolates. Cluster I contained all HS:19 strains, and a single ET (ET4) accounted for most HS:19 strains. HS:19 strains did not occur in any of the other clusters. ET4 contained isolates from different geographic locations, indicating global spread of this clone. Furthermore, ET4 contained isolates from patients with uncomplicated enteritis and GBS, as well as isolates from animal sources. The results of this study show that HS:19 strains comprise a clonal, although not monomorphic, population, which is distinct from non-HS:19 strains within C. jejuni. A unique clone associated with GBS was not identified by use of MLEE.

The widening array of recognized enteric pathogens and the increasing demand for cost-containment sharpen the need for careful clinical and public health guidelines based on the best evidence currently available. Adequate fluid and electrolyte replacement and maintenance are key to managing diarrheal illnesses. Thorough clinical and epidemiological evaluation must define the severity and type of illness (e.g., febrile, hemorrhagic, nosocomial, persistent, or inflammatory), exposures (e.g., travel, ingestion of raw or undercooked meat, seafood, or milk products, contacts who are ill, day care or institutional exposure, recent antibiotic use), and whether the patient is immunocompromised, in order to direct the performance of selective diagnostic cultures, toxin testing, parasite studies, and the administration of antimicrobial therapy (the latter as for traveler's diarrhea, shigellosis, and possibly Campylobacter jejuni enteritis). Increasing numbers of isolates resistant to antimicrobial agents and the risk of worsened illness (such as hemolytic uremic syndrome with Shiga toxin-producing Escherichia coli O157:H7) further complicate antimicrobial and antimotility drug use. Thus, prevention by avoidance of undercooked meat or seafood, avoidance of unpasteurized milk or soft cheese, and selected use of available typhoid vaccines for travelers to areas where typhoid is endemic are key to the control of infectious diarrhea.

To determine whether GM1-like epitopes in Campylobacter species are specific to O serotypes associated with Guillain-Barre syndrome (GBS) or whether they are frequent among random Campylobacter isolates causing enteritis, 275 random enteritis-associated isolates of Campylobacter jejuni were analyzed. To determine whether GM1-like epitopes in Campylobacter species are specific to O serotypes associated with Guillan-Barre syndrome (GBS) or whether they are frequent among random Campylobacter isolates causing enteritis, 275 enteritis-associated isolates, randomly collected in the United States, were analyzed using a cholera-toxin binding assay [corrected]. Overall, 26.2% of the isolates were positive for the GM1-like epitope. Of the 36 different O serotypes in the sample, 21 (58.3%) contained no strains positive for GM1, whereas in 6 serotypes (16.7%), >50% of isolates were positive for GM1. GBS-associated serotypes were more likely to contain strains positive for GM1 than were non-GBS-associated serotypes (37.8% vs. 15.1%, P=.0116). The results suggest that humans are frequently exposed to strains exhibiting GM1-like mimicry and, while certain serotypes may be more likely to possess GM1-like epitopes, the presence of GM1-like epitopes on Campylobacter strains does not itself trigger GBS.

Objective: This study was designed to determine if the presence of specific ganglioside-like moieties in Campylobacter lipopolysaccharides(LPSs) is related to the development of Guillain-Barré syndrome (GBS), and to discover how frequently such moieties, including GM1, are present in these LPSs.Methods: We studied Campylobacter isolates and sera from seven patients with GBS (five acute motor axonal neuropathy, one acute inflammatory demyelinating polyneuropathy, and one Fisher's syndrome), and compared them with similar specimens from patients with Campylobacter enteritis alone.Results: All GBS patients had antiganglioside antibodies. Anti-GM1 and anti-GD1a titers were significantly elevated in post-Campylobacter GBS, both axonal and demyelinating, compared with normal control subjects or those with uncomplicated Campylobacter diarrhea. Campylobacter isolated from patients with GBS and with enteritis alone had similar ganglioside-like moieties.Conclusions: These results indicate that patients who develop GBS respond differently to the ganglioside-like epitopes on Campylobacter than do non-GBS diarrhea patients. Our findings support a role for host susceptibility as a determinant for the outcome following Campylobacter infection. These findings have important implications for the development of vaccines against Campylobacter jejuni.

We evaluated the ability of BBL CHROMagar MRSA medium (Becton Dickinson, Sparks, MD) to identify methicillin-resistant Staphylococcus aureus (MRSA) directly upon subculture from positive blood culture bottles. There were 124 MRSA isolates recovered from blood cultures in the study. BBL CHROMagar MRSA medium was highly sensitive (97.6% [121/124] at 18 to 24 h of incubation and 100% [124/124] at 48 h) and 99.9% specific for identifying MRSA from positive blood cultures.

Molecular techniques can detect drug resistance in Mycobacterium tuberculosis, but whether these methods are practical for clinical laboratory use and the management of tuberculosis is unclear. We evaluated several available molecular methods (restriction fragment length polymorphism [RFLP], heteroduplex, and direct DNA sequence analyses) for detecting resistance to isoniazid, rifampin, and streptomycin and compared these methods with conventional methods for susceptibility testing. RFLP analysis detected the mutation at position S315T in katG in 12 (44.4%) of 27 isoniazid-resistant strains. Heteroduplex analysis of rpoB, detected 16 (76.2%) of 21 rifampin-resistant strains, whereas direct DNA sequencing detected all rifampin-resistant strains. RFLP analysis of the rpsL gene detected only nine (28.1%) of 32 streptomycin-resistant strains, while direct DNA sequencing detected nearly 68% of streptomycin-resistant strains. The specificity of all of the above-mentioned methods was excellent. RFLP analysis for katG and direct DNA sequencing of rpoB and rpsL may be practical methods for routine use in clinical microbiology laboratories or molecular pathology laboratories with good molecular capabilities and autosequencers. Despite the less than optimal sensitivity for some assays, resistance can be detected rapidly. However, molecular methods are not yet capable of replacing more traditional methods of susceptibility testing for M. tuberculosis.

We performed a retrospective study on patients who had a positive screening antibody test result for antibody to Borrelia burgdorferi to determine the clinical indicators used by physicians to order this test. Eighty-two evaluable patients who were screen positive (indirect enzyme-linked immunosorbent assay) between August 1991 and March 1993 were included. Additional tests, isotype-specific capture immunoglobulin enzyme immunoassay and Western blot (immunoblot) analysis (immunoglobulin G), were performed on positive samples. Of 82 patients with a positive screening test result, 54 (66%) had no serologic evidence of Lyme disease on the basis of additional testing (positive predictive value, 34%). Only 28 of 82 patients (34%) had clinical indicators suggestive of Lyme disease. Antibody screening tests may provide misleading information if they are not accompanied by more specific assays. Inappropriate testing of patients without indications of Lyme disease is frequently performed, and the ordering practices of physicians should be reassessed.

We recently developed a molecular typing system for Campylobacter jejuni and Campylobacter coli based on restriction fragment length polymorphism analysis of the flagellin gene,flaA (I.Nachamkin, K. Bohachick, and C.M. Patton, J. Clin. Microbiol. 31:1531-1536, 1993). We extended the typing system to 83 flagellin types (designated flaA-1,flaA-2, etc.) on the basis of analysis of 404 isolates of C. jejuni and C. coli including common serotypes isolated in the United States, a selection of less common serotypes, and serotype reference strains. Of the 295 strains previously shown to belong to common HL and O serotypes (C. M. Patton, M.A. Nicholson, S.M. Ostroff, A.A. Ries, I.K. Wachsmuth, and R.V. Tauxe, J. Clin. Microbiol. 31:1525-1530, 1993), six flaA types accounted for 53.6% of strains as follows: flaA-1, 21.7%; flaA-7, 14.9%; flaA-27, 5.1%; flaA-49, 4.4%; flaA-13, 3.7%; and flaA-21, 3.7%. Seventy-five percent of the strains were within 15 flaA types, 90% were within 30 flaA types, and all 295 strains were contained within 52 flaA types. Within each HL or O serotype, there usually were multiple flaA types. For 12 common HL serotypes and 7 common O serotypes, more than 50% of these isolates were a single flaA type. A database was developed by using commercially available restriction fragment length polymorphism analysis software (ProRFLP; DNA ProScan, Inc., Nashville, Tenn.) that should allow other investigators to perform typing with this system.

In acute motor axonal neuropathy (AMAN), immunoglobulin (Ig) G is deposited on the axolemma of the spinal anterior roots. This indicates that IgG, which binds effectively with complement, is an important factor in the development of AMAN. Patients who developed AMAN subsequent to Campylobacter jejuni enteritis had IgG antibodies against GM1, and their autoantibody titers decreased with the clinical course. Various ganglioside immunization protocols were examined to refine the procedure for establishing an animal model of AMAN. The most effective was subcutaneous injection of an emulsion of 2.5 mg of bovine brain ganglioside (BBG) mixtures, keyhole lympet hemocyanin (KLH) and complete Freund’s adjuvant (CFA), to Japanese white rabbits, with repeated injections at 3-week intervals. Under that protocol, all the rabbits developed marked flaccid paralysis associated with increased plasma anti-GM1 IgG antibody levels. Secondary breakdown of axons under severe demyelination in Guillain-Barre syndrome (GBS) patients has been reported. Electrophysiological evaluations were made for three rabbits inoculated with BBG, seven with GM1, eight with galactocerebroside (GalC), and seven control animals. In the AMAN rabbit model, despite marked limb weakness in the acute phase of the illness, neither compound muscle action potential amplitudes nor motor conduction velocities showed obvious changes, indicating that distal motor nerve conduction was preserved. Intravenous immunoglobulin (IVIG) is effective for GBS in shortening recovery time, but the mechanism of action has yet to be clarified. Anti-idiotypic antibodies in IVIG may affect antibody production by sending negative signals to B cells.

Campylobacter jejuni, an important cause of human gastrointestinal infection, is a major food-borne pathogen in the United States and worldwide. Since poultry becomes colonized and/or contaminated during the early stages of production and is a major food-borne source for this organism, we studied the role of C. jejuni flagella on the ability of the bacterium to colonize the chicken gastrointestinal tract. Three-day-old chicks were orally challenged with a motile wild-type strain of C. jejuni IN9 or with flagellar mutants created from IN9 by disrupting the flagellin genes with a kanamycin resistance cassette by using shuttle mutagenesis (A. Labigne-Roussel, P. Courcoux, and L. Tompkins, J. Bacteriol. 170:1704-1708, 1988). One mutant, IN9-N3, lacked flagella and was nonmotile. The other, IN9-N7, produced a truncated flagellum and was partially motile. Three-day-old chicks were orally challenged with different doses of the wild-type strain and the two mutants. At challenge doses ranging from 3.0 x 10(4) to 6.6 x 10(8) CFU per chick, only the fully motile, wild-type strain colonized the chick ceca. Our results show that intact and motile flagella are important colonization factors for C. jejuni in chicks.

To determine if the leukocyte esterase and bacterial nitrite rapid dipstick test for urinary tract infection (UTI) is susceptible to spectrum bias (when a diagnostic test has different sensitivities or specificities in patients with different clinical manifestations of the disease for which the test is intended).Cross-sectional study.A total of 366 consecutive adult patients in whom clinicians performed urinalysis to diagnose or exclude UTI.An urban emergency department and walk-in clinic.After the patient encounter, but before dipstick test or culture was done, clinicians recorded the signs and symptoms that were the basis for suspecting UTI and for performing a urinalysis and an estimate of the probability of UTI based on the clinical evaluation. For all patients who received urinalysis, dipstick tests and culture were done in the clinical microbiology laboratory by medical technologists blinded to clinical evaluation. Sensitivity for the dipstick was calculated using a positive result in either leukocyte esterase or bacterial nitrite, or both, as the criterion for a positive dipstick, and greater than 10(5) CFU/mL for a positive culture.In the 107 patients with a high (greater than 50%) prior probability of UTI, who had many characteristic UTI symptoms, the sensitivity of the test was excellent (0.92; 95% CI, 0.82 to 0.98). In the 259 patients with a low (less than or equal to 50%) prior probability of UTI, the sensitivity of the test was poor (0.56; CI, 0.03 to 0.79).The leukocyte esterase and bacterial nitrite dipstick test for UTI is susceptible to spectrum bias, which may be responsible for differences in the test's sensitivity reported in previous studies. As a more general principle, diagnostic tests may have different sensitivities or specificities in different parts of the clinical spectrum of the disease they purport to identify or exclude, but studies evaluating such tests rarely report sensitivity and specificity in subgroups defined by clinical symptoms. When diagnostic tests are evaluated, information about symptoms in the patients recruited for study should be included, and analyses should be done within appropriate clinical subgroups so that clinicians may decide if reported sensitivities and specificities are applicable to their patients.

The organization of the flagellin gene locus in Campylobacter jejuni strain IN1 (Lior 7) was determined using the polymerase chain (PCR) reaction and a series of oligonucleotide primers. Two tandemly arranged flagellin genes of approximately 1.7 kb were found to be joined by an intervening segment of c.0.2kb, similar to that reported for Campylobacter coli. The 5' flagellin gene, flaA, was generated by PCR and both strands sequenced. Comparison of the deduced amino acid sequence for C. jejuni FlaA with the published sequence for C. jejuni FlaA with the published sequence for C. coli FlaA showed 77% identical amino acids between the proteins. Two common regions, C1 and C2, comprising the N-terminal 170 amino acids and C-terminal 100 amino acids, exhibit amino acids 94% and 96% identical to those of C. coli, respectively. The variable region, V1, comprising the middle of the protein, shows 61% identical residues with C. coli. Comparison of these regions with other bacterial flagellins reveals a similar pattern but with much less identity. Several areas within the V1 region correspond to predicted surface-exposed regions and may represent areas in which surface epitopes are located.

We studied the ability of a new DNA probe-based assay system to correctly identify isolates of the thermophilic campylobacters Campylobacter jejuni, C. coli, and C. laridis grown in vitro. We examined 424 organisms, including 214 Campylobacter isolates and 210 other aerobic and anaerobic isolates. The probe assay, which uses a new homogeneous system in which all reactions take place within a single tube, demonstrated 100% accuracy, producing neither false-positive nor false-negative results. The assay does not, however, distinguish among C. jejuni, C. coli, and C. laridis.

A commercial latex agglutination test [Meritec-Campy (jcl), Meridian Diagnostics, Cincinnati, Ohio] was evaluated for identification of Campylobacter jejuni, C. coli, C. laridis, and other Campylobacter isolates. The test had 100% sensitivity in detecting C. jejuni and C. coli but low sensitivity with C. laridis isolates. C. upsaliensis strains reacted with the test. The test had 100% specificity for 101 non-Campylobacter organisms.

To determine the clinical, behavioral or demographic factors associated with asymptomatic bacterial vaginosis (BV) and to examine if women with asymptomatic BV had a higher risk of a variety of pregnancy outcomes compared to symptomatic BV positive women. For this study, 1916 pregnant women who were 12 weeks’ gestation or less were enrolled. Interviewers facilitated vaginal swab collection for BV assessment, and completed the baseline questionnaire. BV was identified by Gram stain. Forty percent of pregnant women screened positive for BV and a substantial proportion of BV positive pregnant women were asymptomatic (67%). Asymptomatic BV positive women reported lower stress scores (RR = 0.78, 95% CI: 0.67–0.89), slightly more prior STD’s (RR = 1.03, 95% CI: 1.01–1.07), and a higher quantity of Mobiluncus (RR = 1.04 95% CI: 1.01–1.07) compared to symptomatic BV positive women. We did not find an increase in adverse pregnancy outcomes related to BV symptomatology. Among first trimester pregnant women, only stress, STD history, and quantity of Mobiluncus were associated with symptom reports among BV positive pregnant women. We also found that women with asymptomatic BV did not have an increased risk of a variety of adverse pregnancy outcomes compared to symptomatic BV positive women.

Purpose Pseudomonas aeruginosa infections have been associated with considerable morbidity and mortality. Fluoroquinolones (FQ) are the only oral therapy available for P. aeruginosa infections, but resistance is increasingly prevalent. Methods We examined annual trends in FQ-resistant P. aeruginosa (FQRPA) from 1991 to 2000. Subsequently, inpatients with a clinical culture positive for P. aeruginosa between January 1, 1999 and December 31, 2000 were included in a case control study to identify risk factors for FQ resistance and a cohort study to examine the impact of FQ resistance on outcomes in P. aeruginosa . Results Annual prevalence of FQRPA increased from 15% in 1991 to 41% in 2000 ( P P. aeruginosa isolates were FQ resistant and 540 were FQ susceptible. Prior FQ use was the only independent risk factor for FQRPA (adjusted OR=3.43; 95% confidence interval [CI] 2.37, 4.96). Subjects with FQRPA had greater median hospital charges ($62,325 vs $48,734) ( P =.007) and higher mortality (47.5% vs 35.5%) ( P =.004). However, in a multivariate model, only imipenem resistance of the isolate was significantly associated with mortality. FQ resistance was not an independent risk factor. Conclusions FQRPA has increased significantly and is associated with prior FQ use. Limiting FQ use may curb the emergence of resistance among P. aeruginosa. FQRPA is associated with increased hospital charges, but other resistance patterns may have a more significant impact on mortality.

We evaluated the Syva MicroTrak Chlamydia Blocking Antibody Assay as a confirmatory assay for the detection of Chlamydia trachomatis in urogenital specimens. During a 5-month period, 109 positives were obtained (4.9%) by the MicroTrak II Enzyme Immunoassay as implemented with the Syva XL automated enzyme immunoassay instrument. Of 98 evaluable samples, 92 (93.9%) were confirmed as positive by the blocking assay, and 3 blocking-negative samples had organisms detected by directfluorescent-antibody analysis (blocking sensitivity, 96.8%). We found that direct fluorescent-antibody analysis of samples with a specimen-to-cutoff absorbance ratio of

To the Editor.—We read Dr Cheng's article with interest regarding the prevalence rate ofCampylobacter pylori. Fourteen (70%) of 20 patients with chronic gastritis and 8 (67%) of 12 patients with duodenitis had Cpyloriinfection.1 We performed a similar prevalence study at the University of Pennsylvania, Philadelphia. On approval of the Human Research Committee, 50 consecutive patients who were to undergo elective esophagogastroduodenoscopy were enrolled in the study. Three antral biopsy specimens were obtained for histologic and microbiologic analysis. Chronic nonspecific gastritis was determined by an increase in chronic inflammatory cells, with typical degenerative/regenerative epithelial changes. Gastritis was termed inactive if neutrophils were absent. Acute gastritis was graded as mild, moderate, or severe by the number of neutrophils.Campylobacter-like organisms were detected using acridineorange and hematoxylin-eosin stains. One biopsy specimen was plated onBrucellaagar with 5% sheep blood, hemin, and vitamin K (Remel Laboratories, Lenexa

In our nursery, we identified neonates with positive urine latex particle agglutination (LPA) tests for group B streptococcus (GBS) antigen who did not have corroborating cultural evidence of infection. To investigate the mechanisms underlying these apparent false-positive reactions, we examined the urine LPA test in an unselected population of neonates suspected of sepsis. Urine specimens for LPA testing and culture and simultaneous perirectal cultures were obtained from 134 neonates with suspected sepsis. Six infants had positive blood cultures for GBS; four of the six were positive by LPA testing. An additional 20 infants had positive LPA tests but negative blood cultures; of these, 13 had mothers who received antibiotic treatment prior to delivery. Two infants with positive LPA results and negative blood cultures had bacteria isolated from urine cultures obtained in a nonsterile fashion (GBS, Escherichia coli). GBS was not isolated from perirectal swabs of infants with positive LPA tests and negative blood cultures. In conclusion, (i) a high proportion of neonates evaluated for sepsis gave positive LPA tests and negative blood cultures, (ii) local contamination of the perirectal skin or urinary tract with GBS was an unlikely source of false-positive LPA reactions, and (iii) maternal antibiotic pretreatment during labor may represent an important cause of apparent false-positive LPA reactions.

Prototheca zopfii was isolated from a patient with olecranon bursitis. Olecranon bursitis caused by Prototheca is a distinct clinical entity. Recognition of this infection was made by observing characteristic organisms in tissue and subsequent isolation of the organism.

We measured isotype-specific human antibodies directed against Campylobacter jejuni native flagellin and a synthetic peptide derived from the N-terminal amino acid sequence of the protein by using a microdilution enzyme-linked immunosorbent assay (ELISA). Serum samples from patients with gastrointestinal infection caused by C. jejuni (n = 20) and control samples (number from normal subjects = 20; number from patients with diarrhea other than campylobacter = 20) were tested in this assay. Serum specimens from patients with campylobacter infection showed statistically significant higher isotype-specific antiflagellin antibody titers than control samples did. Detection of immunoglobulin G (IgG) antibodies was less specific (70%) than detection of either IgA or IgM antibodies in infected patients (95%). The sensitivity of testing for any of the isotypes ranged from 64 to 100% in acute-phase serum specimens and 85 to 95% in convalescent-phase serum specimens. An ELISA with an N-terminal synthetic peptide derived from the flagellin protein as antigen was not sensitive (60%) for detecting campylobacter infection but was very specific (97.5%). In conclusion, detection of serum IgA or IgM against C. jejuni flagellin may be a useful marker of infection. Although the N-terminal synthetic peptide was antigenic in a few patients with infection and showed good specificity in the ELISA, additional amino acid sequences with better sensitivity for detecting infection need to be identified.

Isoelectric focusing analysis was performed on flagellins purified from serologically different isolates of Campylobacter jejuni. C. jejuni flagellin exhibits charge heterogeneity with 5 acidic bands demonstrated (pI 4.7–5.7). When immunoblotting was performed with polyclonal human sera, all charged species reacted. However, monoclonal antibody 10–44, specific for a common epitope of Campylobacter sp. flagellin, exhibited binding to predominantly 1 of the 6 bands.

We describe a simplified method for obtaining highly purified flagellin, suitable for biochemical analysis using HPLC-gel permeation. Amino acid composition and N-terminal sequence analyses were performed on flagellins from serologically distinct isolates. The amino acid composition of flagellin from 10 strains was very similar. The N-terminal amino acid sequence is highly conserved. Significant sequence homology was found with flagellin of Bacillus subtilis.

We studied the clinical and immunologic features of 10 patients with foreign body granulomatosis associated with injection of pentazocine. Five had typical micronodules on chest radiographs, 9 had abnormal 67Ga lung images, and 9 had elevated serum angiotensin-converting enzyme levels. Pulmonary function tests showed significant decreases in diffusing capacity in 8 subjects, but were otherwise normal. Bronchoalveolar lavage fluid had significantly (p less than 0.02) increased total cell numbers (13.8 +/- 7.5 x 10(7) and significantly lower percentages of lymphocytes (2 +/- 1) and neutrophils (2 +/- 1) (p less than 0.02) when compared with that from control subjects. Peripheral blood lymphocytes were normal when expressed as percentages of total leukocytes or as percent T-lymphocytes. Monoclonal antibody determinations of T-lymphocyte subsets (helper and suppressor) were similar to those in control subjects (p = NS). Lymphocyte transformation responses to a variety of antigens and skin test reactivity were normal. Foreign body granulomatosis contrasts with other interstitial lung diseases in its bronchoalveolar lavage cellular profile and in the absence of altered peripheral immunologic indexes.

The authors evaluated the usefulness of direct wet mount microscopic examination of stool samples for routine parasitologic diagnosis compared with formalin-ethyl acetate concentration detection. Over a three-year period, there were no instances in which an intestinal parasite was detected only by the direct wet mount examination. Elimination of routine direct wet mount examinations can reduce laboratory cost and save significant technologist time without decreasing the sensitivity of microscopic examinations for common parasitic agents.

The authors performed a prospective clinical evaluation of the Gonozyme (Abbott Laboratories, Chicago, IL) assay in a family planning clinic population. One thousand five hundred eighty-eight female patients were screened for gonococcal infection using culture and Gonozyme assay. One hundred nine patients were culture positive (6.9% disease prevalence). The sensitivity and specificity of the Gonozyme assay in this setting was 87.2% and 89.1%, respectively. The predictive value of a positive and negative test, given a disease prevalence of 6.9%, was 37.2% and 98.9%, respectively. The false-positive and false-negative rate was 10.9% and 12.8%, respectively. The authors prospectively followed patients with true-positive and false-positive Gonozyme results. The Gonozyme test showed a 83% correlation with test of cure cultures and, thus, should not be used for test cure analysis. False-positive Gonozyme tests could not be explained on the basis of cross-reacting bacteria or detection of vancomycin-sensitive gonococci. The authors' results suggest that the Gonozyme test should not be used in lieu of culture in a clinical setting with a similar population.The authors performed a prospective, clinical evaluation of the Gonozyme assay in a family planning clinic population. 1588 female patients were screened for gonococcal infection using culture and Gonozyme assay. 109 patients were culture positive (6.9% disease prevalence). The sensitivity and specificity of the Gonozyme assay in this setting was 87.2% and 89.1% respectively. The predictive value of a positive and negative test, given a disease prevalence of 6.9%, was 37.2% and 98.9%, respectively. The false positive and false negative rate was 10.9% and 12.8% respectively. The authors prospectively followed patients with true positive and false positive Gonozyme results. The Gonozyme test showed an 83% correlation with test of cure cultures and, thus, should not be used for test of cure analysis. False positive Gonozyme tests could not be explained on the basis of cross-reacting bacteria or detection of vancomycin sensitive gonococci. Results suggest that the Gonozyme test should not be used in lieu of culture in a clinical setting with a similar population.

The direct immunofluorescence assay (DFA) was compared with culture for test-of-cure analysis for Chlamydia trachomatis in patients 7 to 10 days after antimicrobial therapy was given. DFA test-of-cure results correlated with culture results in 79.5% of 39 patients. Of DFA-negative patients, 97% had negative cultures. Six of seven patients with borderline DFA results had negative culture results.