Human granulocytic ehrlichiosis is a recently described disease caused by an obligate intracellular gramnegative organism recently named Ehrlichia phagocytophila. To expand our knowledge of the susceptibility of E. phagocytophila, we tested six New York State isolates for susceptibility to 12 antimicrobials using an HL-60 cell culture system. All of the isolates were susceptible to doxycycline (MIC, <0.125 g/ml; minimum bactericidal concentration [MBC], 0.125 to 0.5 g/ml), rifampin (MIC, <0.125 g/ml; MBC, <0.125 g/ml), ofloxacin (MIC, <2 g/ml; MBC, <2 g/ml), levofloxacin (MIC, <1 g/ml; MBC, <1 g/ml), and trovafloxacin (MIC, <0.032 g/ml; MBC, <0.032 g/ml). Isolates were uniformly resistant to amoxicillin, ceftriaxone, erythromycin, azithromycin, clarithromycin, and amikacin. For one strain, the MBC of chloramphenicol was <8 g/ml. These data suggest that quinolone antibiotics and rifampin may be alternative agents for patients with intolerance to tetracyclines.Human granulocytic ehrlichiosis was first described in 1994 (2) and has subsequently been reported from other regions of the United States and from Europe (1, 7, 11). The infection is caused by the obligate intracellular pathogen Ehrlichia phagocytophila. E. phagocytophila is transmitted by Ixodes sp. ticks (10). Patients acutely infected with this organism demonstrate a rapid clinical response to doxycycline therapy (1, 2). Successful outcomes have also been reported in two patients who were treated with rifampin (4) and one who received chloramphenicol (5). However, spontaneous resolution of illness may also occur without any antimicrobial therapy. To date, only three isolates, one of which was from New York State, have been tested for susceptibility to antimicrobials (6). Alternatives to doxycycline are needed for treatment of young children, pregnant women, and patients intolerant of tetracyclines. In order to expand upon the limited existing data, we tested six New York State isolates of E. phagocytophila for susceptibility to a panel of 12 antimicrobials. MATERIALS AND METHODSIsolation and culture of New York E. phagocytophila isolates. The New York E. phagocytophila isolates tested were recovered as described previously from patients suspected of being infected (1, 6). Infected cells were propagated in HL-60 cells using RPMI 1640 medium without antimicrobials and supplemented with 10% heat-inactivated fetal bovine serum (FBS). Culture positivity in HL-60 cells and percent infection were based on detection of morulae in cytospin slide preparations stained with Wright's stain.Sources of antimicrobials. The following antimicrobials were purchased from Sigma Chemical Co. (St. Louis, Mo.): amikacin, amoxicillin, ceftriaxone, chloramphenicol, doxycycline (as the hydrochloride form), erythromycin (as ethyl succinate), ofloxacin, and rifampin. Trovafloxacin mesylate (CP-062, 993-03; lot 25381-087-02) and azithromycin hydrate (CP-009, 219-27; lot 25381-088-02) were obtained from Pfizer (Groton, Conn.). Levofloxacin (RWJ-25213-097-AX) was a gift from R. W. John...
The human granulocytic ehrlichiosis (HGE) agent in infected blood specimens remained viable during refrigeration at 4°C for up to 18 days. These findings suggest that blood specimens submitted for culture may withstand transportation to a remote laboratory. HGE should be added to the list of infections potentially transmitted by blood transfusion.
We evaluated the antibody responses in the sera of 24 patients with culture-confirmed human granulocytic ehrlichiosis (HGE). Antibody titers were measured by an indirect immunofluorescent-antibody assay (IFA) by using a local human isolate as the source of antigen. All patients received appropriate antimicrobial treatment. One hundred five serum specimens collected at baseline and at periodic intervals for up to 14 months were included in the study. Seroconversion was observed in 21 of 23 patients (91.3%) from whom convalescent-phase sera were obtained. Antibodies were first detected at an average of 11.5 days after onset of symptoms. Peak titers (≥2,560 for 71.4% of patients and ≥640 for 95.2% of patients) were obtained an average of 14.7 days after onset of symptoms. Eleven of 13 patients (84.6%) from whom sera were collected between 6 and 10 months after onset of symptoms were still seropositive, and sera from 5 of 10 (50%) patients tested positive between 11 and 14 months after onset of symptoms. For a subset of 71 serum specimens from 17 patients with culture-confirmed HGE also tested by IFA by using either a human isolate from Wisconsin or anEhrlichia equi isolate from a horse, there was qualitative agreement for 62 serum specimens (87.3%). Peak titers were higher, however, with the local human HGE isolate, but the difference was not statistically significant. In summary, most patients with culture-confirmed HGE develop antibodies within 2 weeks of onset of symptoms. Antibodies reach high titers during the first month and remain detectable in about one-half of patients at 1 year after onset of symptoms.
The human granulocytic ehrlichiosis (HGE) agent in infected blood specimens remained viable during refrigeration at 4°C for up to 18 days. These findings suggest that blood specimens submitted for culture may withstand transportation to a remote laboratory. HGE should be added to the list of infections potentially transmitted by blood transfusion.
Urine cytology is a proven and widely used screening tool for the detection of urothelial carcinoma. However, morphologic features of polyomavirus infected cells, characterized by nuclear inclusions (decoy cells) are a known source of diagnostic confusion with malignancy. Fluorescence in situ hybridization (FISH) is now routinely used to support the cytological diagnosis of urothelial carcinoma and monitor for recurrence. We sought to determine whether polyomavirus infection could result in positive FISH results (aneuploidy). This study deals with retrospective study of 100 polyomavirus-infected urine samples from patients with no history of urothelial carcinoma or organ transplantation. All cases were stained with Papanicolaou and acid hematoxylin stain. One slide from each sample was de-stained and FISH was performed using chromosome enumeration probes 3, 7, 17, and locus-specific probe 9p21. Adequate cells for FISH analysis (25 cells) were present in 81 cases; 19 cases were insufficient due to loss of cells during de-staining and FISH preparation process. All polyomavirus-infected cells (decoy cells) exhibited a normal chromosome pattern. Four cases were FISH positive, but there were no positive decoy cells. Decoy cells did not exhibit aneuploidy by FISH. The presence of decoy cells does not exclude the possibility of concurrent urothelial carcinoma. Acid hematoxylin stain appeared to supplement the Papanicolou stain in identifying and confirming the presence of polyomavirus infection.
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