Faculty Bibliography

BACKGROUND: The clinical manifestations of Lyme borreliosis in North America and Europe seem to differ, but a systematic comparison has never been done. OBJECTIVE: To compare European and U.S. patients with culture-confirmed erythema migrans. DESIGN: Prospective, clinical cohort study. SETTING: University medical centers in Westchester County, New York, and Ljubljana, Slovenia. PATIENTS: 119 U.S. patients with Borrelia burgdorferi sensu stricto infection and 85 Slovenian patients with B. afzelii infection. MEASUREMENTS: Interview, physical examination, and laboratory assays. RESULTS: Compared with Slovenian patients, U.S. patients had erythema migrans for a briefer duration (median duration, 4 days compared with 14 days; P < 0.001) but were more likely to have systemic symptoms (P = 0.01), abnormal findings on physical examination (P < 0.001), and seroreactivity (P < 0.001). Central clearing of erythema migrans lesions was more likely in Slovenian patients (P < 0.001). CONCLUSIONS: Erythema migrans caused by B. afzelii in Slovenia and erythema migrans caused by B. burgdorferi in New York have distinct clinical presentations. Caution should be used when clinical and laboratory experience from one side of the Atlantic is applied to patients on the other

We describe the clinical and laboratory manifestations of human granulocytic ehrlichiosis (HGE) in eight patients for whom cultures were positive for the HGE agent and compare them with 15 patients for whom cultures were negative but who fulfilled a modified New York State Surveillance definition for HGE. Polymerase chain reaction analysis was positive in 8 (100%) of 8 culture-positive cases vs. 3 (20%) of 15 culture-negative cases (P < .001), morulae were detected in 7 (100%) of 7 culture-positive cases in which tests were performed vs. 0 of 15 culture-negative cases (P < .001), and a fourfold change in antibody titer was demonstrated in 6 (75%) of 8 culture-positive cases vs. 9 (69%) of 13 culture-negative cases (P = not significant). Patients for whom cultures were positive had higher mean oral temperatures +/- SD at presentation than did patients for whom cultures were negative (38.6 degrees C +/- 0.7 degree C vs. 37.2 degrees C +/- 0.8 degree C, respectively; P = .002). Other symptoms and signs were not significantly different between the two groups. Multivariate analysis revealed that the lymphocyte count at presentation was significantly lower in culture-positive cases than in culture-negative cases. Clinical response to treatment was similar in the two groups. Culture confirmation of HGE is the gold standard for defining the sensitivity and specificity of other diagnostic tests presently being developed

Human granulocytic ehrlichiosis (HGE) is an occasionally severe and even fatal disease caused by an agent closely related to Ehrlichia equi and Ehrlichia phagocytophila, which is transmitted by ticks. Little is known about the pathogen itself, which only very recently has been isolated. The agent can be cultivated in vitro because it replicates in human promyelocytic leukemic HL-60 cells. Using multiparameter flow cytometry and laser scanning cytometry (LSC) we have investigated changes in HL-60 cells following their infection with the pathogen. Its presence within the infected HL-60 cells was detected and its intracellular level measured inmmunocytochemically using antibodies obtained from HGE-infected patients. The percentage of the infected cells measured by flow cytometry or LSC correlated well with the estimates by microscopy on the Giemsa-stained specimens. In the infected cultures, the cells had diminished levels of cyclins D3 and E as well as the cyclin dependent kinase inhibitor p21WAF1/CIP1 and were arrested predominantly in G0/1. The apoptosis-associated regulatory proteins were also affected by cell infection: expression of Bcl-2 was decreased in the infected cells whereas expression of Bax become more variable, with some cells showing higher levels of this protein. The infected cells developed numerous DNA strand breaks characteristic of apoptosis. The presence of the pathogen was also detected by LSC in cells from peripheral blood of the infected patients; after relocation and visual inspection ('CompuSort') the pathogen-positive cells were identified as leukocytes. This unique ability of LSC to detect, quantify, and visualize HGE in infected cells made this instrument particularly useful to measure the degree of infection in peripheral blood of the patients and study effects of the infectious agent on the cell cycle and apoptosis of the host cells

OBJECTIVE: To determine the value of amniotic fluid (AF) complement C3 as a marker of intra-amniotic infection and to compare complement C3 with other rapid markers of intra-amniotic infection. METHODS: One hundred four women with singleton gestations, in preterm labor with intact membranes, at 23-35 weeks' gestation underwent transabdominal amniocentesis. Amniotic fluid was analyzed for white blood cell (WBC) count, lactate dehydrogenase (LDH), glucose, Gram stain, and complement C3. Cultures for aerobes, anaerobes, and mycoplasma species also were performed. The median values of complement C3, WBC, LDH, and glucose were compared between the culture-positive and -negative groups. Complement C3 was compared with WBC count, LDH, glucose, and Gram stain for sensitivity, specificity, positive and negative predictive values, and accuracy in the prediction of a positive AF culture. Descriptive statistics, receiver operating characteristic curve, Fisher exact test, and Wilcoxon rank-sum test were used for analysis. RESULTS: The prevalence of positive cultures was 11.5% (12 of 104). The culture-positive group had a significantly higher median C3 (7.0 mg/dL) than the median C3 (3.0 mg/dL) of the culture-negative group (P < .001). Also, the median values of WBC (1120.5 cells/mm3) and LDH (2697 U/L) were significantly higher and the median glucose (6.5 mg/dL) was significantly lower among women with positive AF cultures than among women with negative AF cultures (WBC=1 cell/mm3; LDH=165 U/L; glucose=45 mg/dL; P < .001). Eleven of the 12 culture-positive cases had a C3 of 5 mg/dL or more, whereas four of the 92 culture-negative cases had a C3 of 5 mg/dL (P < .001). Nine of the 12 culture-positive cases but none of the 92 culture-negative cases had a C3 of 6 mg/dL or more (P < .001). The relative risks of a positive AF culture were 65.27 (95% confidence interval [CI] 9.08, 469.27) and 31.67 (95% CI 10.40, 96.43) times greater among women with AF complement C3 levels of 5 and 6 mg/dL or more, respectively. Depending on the cutoff point used, complement C3 had similar or higher sensitivity, specificity, positive predictive value, and negative predictive value for intra-amniotic infection when compared with WBC count, LDH, glucose and Gram stain. CONCLUSION: Amniotic fluid complement C3 has value in the diagnosis of intra-amniotic infection in preterm labor with intact membranes. Complement C3 is available readily and compares favorably with other rapid markers of AF infection. This study supports the general concept of fetal inflammatory response to microbial invasion of AF

A multicenter, double-blinded, placebo-controlled study was done comparing a 30-microgram dose of a single protein recombinant OspA vaccine preparation with a saline placebo for efficacy in prevention of Lyme disease in humans. The OspA vaccine (30-microgram dose) or saline placebo was given intramuscularly at day 0, 1 month later, and 12 months later. Cases of possible Lyme disease were evaluated clinically and using culture, polymerase chain reaction and immunoblot assays. Safety data are being analyzed separately. 1,634 adult volunteers were enrolled at a single center in New York State. Vaccine efficacy during the first year was 40% and during the second 37%. Compared with placebo, the OspA vaccine significantly reduced the frequency of Lyme disease during the 2-year study period (P < 0.04, one-tailed Fisher's exact test). Vaccine efficacy was restricted to volunteers under 60 years old (50% vs 9%, P < 0.03, two-tailed Fisher's exact test). A recombinant OspA vaccine preparation was found to have moderate activity in preventing Lyme disease in adults under 60 years old from New York State. Reasons for vaccine failure need to be addressed and a risk benefit ratio calculated

The agent of human granulocytic ehrlichiosis (HGE), Ehrlichia phagocytophila, and Ehrlichia equi are very similar. HGE is of variable severity. Genetic and antigenic differences among 3 human isolates (Webster, Spooner, and NY-8) and 1 horse isolate (MRK) were evaluated. The 16S rRNA gene sequences were identical in all human isolates. By use of 5 homologous antisera from these 3 humans and 1 horse and an additional 5 antisera in heterologous reactions, the immunodominant antigens of each isolate were noted to differ in molecular size: 43 kDa in the Webster (Wisconsin) isolate, 46 kDa in the Spooner (Wisconsin) isolate, 42 and 45 kDa in the NY-8 (New York State) isolate, and a 42 kDa doublet in the E. equi MRK isolate from California. Two sera from a Wisconsin patient reacted weakly or not at all with the NY-8 isolate. Antigenic structural diversity exists among otherwise indistinguishable granulocytic ehrlichial isolates