Human Infection with<i>Ehrlichia canis</i>, a Leukocytic Rickettsia

Maeda, Koichi; Markowitz, Norman; Hawley, Robert; Ristić, M; Çox, Donald C.; McDade, Joseph E.

doi:10.1056/nejm198704023161406

Cited by 434 publications

(56 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…E. chaffeensis, the cause of human monocytic ehrlichiosis, was described first in 1987 and is the most common agent of human ehrlichiosis (47). E. ewingii was reported as a human pathogen in 1999 after being detected in peripheral blood leukocytes of four patients with illness during 1996-1998 (48).…”

Section: Ehrlichiaementioning

confidence: 99%

Diagnosis and Management of Tickborne Rickettsial Diseases: Rocky Mountain Spotted Fever and Other Spotted Fever Group Rickettsioses, Ehrlichioses, and Anaplasmosis — United States

Biggs¹,

Behravesh²,

et al. 2016

View full text Add to dashboard Cite

Section: Ehrlichiaementioning

confidence: 99%

Diagnosis and Management of Tickborne Rickettsial Diseases: Rocky Mountain Spotted Fever and Other Spotted Fever Group Rickettsioses, Ehrlichioses, and Anaplasmosis — United States

Biggs¹,

Behravesh²,

et al. 2016

View full text Add to dashboard Cite

“…Human monocytic ehrlichiosis (HME), first reported in 1987, is caused by Ehrlichia chaffeensis (4,10,16). Early symptoms of HME include fever, headache, malaise, muscle aches, vomiting, diarrhea, cough, joint pains, and confusion (33).…”

mentioning

confidence: 99%

Molecular Heterogeneity of Ehrlichia chaffeensis Isolates Determined by Sequence Analysis of the 28-Kilodalton Outer Membrane Protein Genes and Other Regions of the Genome

2003

View full text Add to dashboard Cite

Ehrlichia chaffeensis, a tick-transmitted rickettsial agent, is responsible for human monocytic ehrlichiosis (HME). In this study, we genetically mapped 10 isolates obtained from HME patients. Sequence analysis of the 28-kDa outer membrane protein (OMP) multigene locus spanning 6 of the 22 tandemly arranged genes identified three distinct genetic groups with shared homology among isolates within each group. Isolates in Groups I and III contained six genes each, while Group II isolates had a gene deletion. There were two regions on the locus where novel gene deletion or insertion mutations occurred, resulting in the net loss of one gene in Group II isolates. Numerous nucleotide differences among genes in isolates of each group also were detected. The shared homology among isolates in each group for the 28-kDa OMP locus suggests the derivation of clonal lineages. Transcription and translation analysis of the locus revealed differences in the expressed genes of different group isolates. Analysis of the 120-kDa OMP gene and variable-length PCR target gene showed size variations resulting from loss or gain of long, direct repeats within the protein coding sequences. To our knowledge this is the first study that looked at several regions of the genome simultaneously, and we provide the first evidence of heterogeneity resulting from gene deletion and insertion mutations in the E. chaffeensis genome. Diversity in different genomic regions could be the result of a selection process or of independently evolved genes.

show abstract

“…Acute, febrile illnesses with severe headache, muscle aches, nausea, and diminished platelet and white blood cell counts, as well as abnormal liver function tests, follow exposure to ticks (1). The index case of human ehrlichiosis in the United States occurred in Arkansas in 1985 and was due to infection by a predominantly monocyteinhabiting organism designated Ehrlichia chaffeensis (2,3). This new agent has infected about 400 individuals from 30 states, with 12 fatalities (unpublished data).…”

mentioning

confidence: 99%

Perpetuation of the agent of human granulocytic ehrlichiosis in a deer tick-rodent cycle.

Telford

Dawson

Katavolos

et al. 1996

Proc. Natl. Acad. Sci. U.S.A.

462

371

View full text Add to dashboard Cite

Propagation of the Agent of HGE. Blood (EDTA anticoagulated) was obtained from a Nantucket patient with HGE whose infection was confirmed by blood smear and sequencing of a 16S rDNA amplification product (8), and 0.5 ml was inoculated i.p. into a splenectomized CD-1 mouse. Buffy coat preparations (equivalent to 1 ml of whole blood, centrifuged at 2500 x g for 10 min) were inoculated i.p. into two intact C3H/HeJ mice. Plasma (0.5 ml) was inoculated into one C3H/HeJ mouse as well. To determine whether ehrlichiae were present in the peripheral blood, thin blood smears were taken from the tails of rodents, dried, fixed for 2 min in absolute methanol, and stained with 1 ml Giemsa stock (Harleco Original Azure Blend; EM Diagnostic Systems, Princeton, NJ) diluted in 40 ml distilled water with 150 ptl of 0.5% Na2CO3 and 1.25 ml methanol for 1 hr or more (9

show abstract

Human Infection withEhrlichia canis, a Leukocytic Rickettsia

Cited by 434 publications

References 8 publications

Diagnosis and Management of Tickborne Rickettsial Diseases: Rocky Mountain Spotted Fever and Other Spotted Fever Group Rickettsioses, Ehrlichioses, and Anaplasmosis — United States

Diagnosis and Management of Tickborne Rickettsial Diseases: Rocky Mountain Spotted Fever and Other Spotted Fever Group Rickettsioses, Ehrlichioses, and Anaplasmosis — United States

Molecular Heterogeneity of Ehrlichia chaffeensis Isolates Determined by Sequence Analysis of the 28-Kilodalton Outer Membrane Protein Genes and Other Regions of the Genome

Perpetuation of the agent of human granulocytic ehrlichiosis in a deer tick-rodent cycle.

Contact Info

Product

Resources

About