11/22. Human monocytic ehrlichiosis.A 56-year-old man with a history of wegener granulomatosis presented with 6 days of sinus congestion, fever, malaise, myalgias, episcleritis, and a morbilliform rash. An exacerbation of wegener granulomatosis was the principal concern because of the frequency of flares in that disease. The patient developed acute renal failure, thrombocytopenia, transaminitis, and, finally, severe myocarditis that led to congestive heart failure. Additional history-taking and the evolution of his clinical features led to empirical treatment with doxycycline for human monocytic ehrlichiosis (HME). The diagnosis of HME was confirmed by both a polymerase chain reaction assay for ehrlichia chaffeensis and by the demonstration of morulae within peripheral blood mononuclear cells. The patient improved promptly following institution of doxycycline, and his cardiac function returned to normal over a period of 4 months.- - - - - - - - - - ranking = 1keywords = lyme (Clic here for more details about this article) |
12/22. Concomitant tickborne encephalitis and human granulocytic ehrlichiosis.We report a patient with febrile illness and epidemiologic and clinical findings consistent with human granulocytic ehrlichiosis and tickborne encephalitis, in whom infection with anaplasma phagocytophilum was demonstrated by polymerase chain reaction and seroconversion. Tickborne encephalitis virus infection was established by serum immunoglobulin (Ig) M and IgG antibodies.- - - - - - - - - - ranking = 1keywords = lyme (Clic here for more details about this article) |
13/22. ixodes dammini as a potential vector of human granulocytic ehrlichiosis.Little is known about the epidemiology and mode of transmission of the agent of human granulocytic ehrlichiosis (HGE). Analyses of an engorged female ixodes dammini tick removed from an HGE patient and 101 field-collected I. dammini and dermacentor variabilis from three wisconsin counties for borrelia burgdorferi and Ehrlichia phagocytophila/Ehrlichia equi dna revealed that the patient tick and 7 of 68 I. dammini ticks from Washburn County collected in 1982 and 1991 were positive for ehrlichial dna; 10 ticks from the same collections were positive for B. burgdorferi. Two specimens (2.2%) were positive for both organisms. Serologic evidence for exposure to the agent of HGE or its relatives was detected in 3 of 25 lyme disease patients from the upper Midwest. These data argue that I. dammini is a common vector for transmission of both lyme disease and HGE.- - - - - - - - - - ranking = 148.80966682009keywords = burgdorferi (Clic here for more details about this article) |
14/22. ehrlichiosis mimicking thrombotic thrombocytopenic purpura. Case report and pathological correlation.Human ehrlichiosis is a tick-borne zoonosis caused by the newly described human hematotropic rickettsiae, ehrlichia chaffeensis. The pathology and pathogenesis of human ehrlichiosis have not been adequately studied. Even with immunoperoxidase, the only previously known method to detect these organisms in tissue, ehrlichae are difficult or impossible to identify. This led many investigators to speculate that the pathogenesis of ehrlichiosis was not caused directly by the organism but could be caused by host-mediated injury. In this case study, a patient presented with rapidly progressive central nervous system symptoms and severe thrombocytopenia, prompting a presumptive diagnosis of thrombotic thrombocytopenic purpura (TTP). Despite corticosteroids, and later, antibiotics, the patient rapidly deteriorated and died. Postmortem examination showed hemorrhages in multiple organs and mononuclear inclusions of infection with a monocytic ehrlichia. Other findings included widespread lymphohistiocytic perivascular infiltrates, focal hepatic necroses, interstitial pneumonitis, interstitial nephritis, mononuclear phagocyte invasion and proliferation in splenic, liver, and bone marrow, and hemophagocytosis. The diagnosis was proven by serology, immunohistology with both polyclonal and monoclonal anti E chaffeensis, and polymerase chain reaction on paraffin-embedded tissues using E chaffeensis-specific oligonucleotide primers. The presence of numerous ehrlichia with notable tissue and cellular injury but without a marked host response indicate that unlike other cases of documented human ehrlichiosis, this patient died after significant direct ehrlichia-mediated injury, and that immune mechanisms initiated after ehrlichiosis played little if any role in the pathogenesis.- - - - - - - - - - ranking = 1keywords = lyme (Clic here for more details about this article) |
15/22. ehrlichiosis--a cause of prolonged fever.Human ehrlichiosis is a recently described illness that is thought to be tick-borne. Most recognized cases of human ehrlichiosis manifest as an acute nonspecific febrile illness. The natural history of untreated symptomatic disease is largely unknown. Over a 4-year period, we identified 41 cases of human ehrlichiosis by serological testing, polymerase chain reaction analysis, or both methods. The principal finding for six of the patients was protracted fever. The duration of their fevers ranged from 17 to 51 days. At the time of presentation, all six patients had clinical features, laboratory features, or both consistent with a diagnosis of ehrlichiosis. polymerase chain reaction analysis helped to rapidly confirm the diagnosis for four of five patients tested. The diagnosis of human ehrlichiosis should be considered for patients with prolonged fever who live in an area of endemicity.- - - - - - - - - - ranking = 2keywords = lyme (Clic here for more details about this article) |
16/22. Human granulocytic ehrlichiosis in the upper Midwest United States. A new species emerging?OBJECTIVE--To characterize the clinical presentation and course, laboratory findings, and treatment outcome of 12 patients with human granulocytic ehrlichiosis. SETTING--The 12 patients were male, ranged in age from 29 to 91 years, and contracted their illness in wisconsin or minnesota. methods--Cases were recognized by the presence of intracytoplasmic inclusions (morulae) in peripheral neutrophils of patients presenting with temperature of 38.5 degrees C or higher, chills, severe headache, and myalgias. All patients had a complete blood cell count and blood chemistry profile. Blood smears were examined by light microscopy. All available paired serum samples were analyzed for presence of indirect fluorescent antibodies against ehrlichia chaffeensis, Ehrlichia phagocytophila, and Ehrlichia equi. Blood samples from 12 patients were subjected to polymerase chain reaction analysis using primers specific for the E phagocytophila/E equi group, primers that include the agent identified in our patients, as well as E chaffeensis. RESULTS--Varying combinations of leukopenia, anemia, and thrombocytopenia were found in all but one patient. All 12 patients demonstrated morulae in the cytoplasm of neutrophils, but not in mononuclear white blood cells. serum assays failed to detect antibodies against E chaffeensis, but eight of 10 patients and seven of 10 patients tested had antibody titers of 1:80 or more for E phagocytophila and E equi, respectively. polymerase chain reaction products obtained with primers for E phagocytophila, E equi, and the granulocytotropic Ehrlichia revealed that seven patients were infected with the same agent. The results of serological assays or polymerase chain reaction strongly suggest that all 12 patients were infected by E phagocytophila, E equi, or a closely related Ehrlichia species. Two of the 12 patients died. The other 10 patients improved rapidly with oral doxycycline treatment. CONCLUSIONS--We believe that all 12 patients have been infected with a granulocytic Ehrlichia species, reflecting a recently described new disease entity. The infective organism appears to be closely related to E phagocytophila and E equi. The geographic domain of human granulocytic ehrlichiosis is currently unknown. This novel granulocytic Ehrlichia species is capable of causing fatal infections in humans. Early detection and treatment with tetracycline drugs appear to offer the best chance for complete recovery.- - - - - - - - - - ranking = 3keywords = lyme (Clic here for more details about this article) |
17/22. Direct cultivation of the causative agent of human granulocytic ehrlichiosis.BACKGROUND. Human granulocytic ehrlichiosis is a potentially fatal tick-borne infection that has recently been described. This acute febrile illness is characterized by myalgias, headache, thrombocytopenia, and elevated serum aminotransferase levels. The disease is difficult to diagnose because the symptoms are non-specific, intraleukocytic inclusions (morulae) may not be seen, and the serologic results are often initially negative. Little is known about the causative agent because it has never been cultivated. methods. We studied three patients with symptoms and laboratory findings suggestive of human granulocytic ehrlichiosis, including unexplained fever after probable exposure to ticks, granulocytopenia, and thrombocytopenia. Peripheral blood was examined for ehrlichia microscopically and with use of the polymerase chain reaction (PCR). Blood was inoculated into cultures of HL60 cells (a line of human promyelocytic leukemia cells), and the cultures were monitored for infection by Giemsa staining and PCR. RESULTS. Blood from the three patients, only one of whom had inclusions suggestive of ehrlichia in neutrophils, was positive for human granulocytic ehrlichiosis on PCR. Blood from all three patients was inoculated into HL60 cell cultures and caused infection, with intracellular organisms visualized as early as 5 days after inoculation and cell lysis occurring within 12 to 14 days. The identity of the cultured organisms was confirmed by immunofluorescence microscopy, PCR analysis, and dna sequencing. dna from the infected cells was sequenced in regions of the 16S ribosomal gene reported to differ between the agent of human granulocytic ehrlichiosis and closely related species, including Ehrlichia equi and E. phagocytophila which cause infection in animals. The sequences from all three human isolates were identical and differed from the strain of E. equi studied in having guanine rather than adenine at nucleotide 84. CONCLUSIONS. We describe the cultivation of the agent of human granulocytic ehrlichiosis in cell culture. The ability to isolate this organism should lead to a better understanding of the biology, treatment, and epidemiology of this emerging infection.- - - - - - - - - - ranking = 1keywords = lyme (Clic here for more details about this article) |
18/22. Human disease in europe caused by a granulocytic Ehrlichia species.Human granulocytic ehrlichiosis (HGE) was recently described in north america. It is caused by an Ehrlichia species closely related to Ehrlichia phagocytophila and Ehrlichia equi, recognized to infect mostly ruminants and horses, respectively. The vector in north america is the tick ixodes scapularis, which is also the vector of the lyme disease agent, borrelia burgdorferi. Previous serologic studies in patients with a diagnosis of Lyme borreliosis indicate that HGE may exist in europe. We report the first documented case of HGE in europe. The diagnosis was established by seroconversion to E. equi and the HGE agent and by PCR with sequence analysis of the gene encoding the HGE agent 16S rRNA. Interestingly, the patient presented with a self-limited but moderately severe illness. Thus, European physicians need to be aware that HGE exists in europe and that the diagnosis should be considered in febrile patients with tick bites in areas where lyme disease is endemic.- - - - - - - - - - ranking = 74.404833410047keywords = burgdorferi (Clic here for more details about this article) |
19/22. Heat shock protein 70 of the agent of human granulocytic ehrlichiosis binds to borrelia burgdorferi antibodies.We describe a patient with human granulocytic ehrlichiosis (HGE), a diagnosis confirmed by PCR and immunoblot analysis. Unexpectedly, immunoglobulin g (IgG) directed towards an 80-kDa ehrlichial antigen (without detectable IgM) was present in the patient's serum in the first week of illness. lyme disease immunoblots were reactive for IgG (but not IgM), a result indicative of prior exposure to the lyme disease spirochete. Amino-terminal sequencing revealed that the 80-kDa ehrlichial antigen was an HSP-70 homolog similar to borrelia burgdorferi HSP-70. We conclude that antibodies against B. burgdorferi HSP-70 may cross-react with the ehrlichial heat shock protein and that this possibility must be considered when serologic test results for HGE and lyme disease are interpreted.- - - - - - - - - - ranking = 446.42900046028keywords = burgdorferi (Clic here for more details about this article) |
20/22. Dual infection with ehrlichia chaffeensis and a spotted fever group rickettsia: a case report.Well-documented cases of simultaneous human infection with more than one tick-borne pathogen are rare. To our knowledge only two dual infections have been reported: simultaneous human infection with the agent of human granulocytic ehrlichiosis and borrelia burgdorferi and simultaneous human infection with B. burgdorferi and babesia microti (1-2). rocky mountain spotted fever has long been known to be endemic in north carolina; cases of human ehrlichial infection were recognized there soon after ehrlichia chaffeensis was recognized as an important cause of tick-borne disease in the southeastern united states. Because both rocky mountain spotted fever and ehrlichiosis are prevalent in north carolina, occasional cases of simultaneous human infection by rickettsial and ehrlichial agents would not be surprising; however, no such cases seem to have been reported.- - - - - - - - - - ranking = 148.80966682009keywords = burgdorferi (Clic here for more details about this article) |
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