Table 6. Reported cases of human ehrlichiosis due to non-canis/non-chaffeensis Ehrlichia species (n = 61).
| Species | Number of cases (n) | Country of infection | Year of publication | Mode of diagnosis (n patients) | Clinical features (n patients) | Laboratory findings (n patients) | Outcome | Comment | Ref. |
|---|---|---|---|---|---|---|---|---|---|
| E. ewingii | 4 | USA | 1999 | PCR (4/4), blood smear (2/4) | Fever (4/4), headache (4/4), myalgia (1/4), neck stiffness (1/4), lymphadenopathy (1/4) | Thrombocytopenia (4/4), anemia (2/4), leukopenia (1/4), abnormal liver-function tests (1/4) | All survived | 3/4 immunocompromised | [7] |
| 1 | USA | 2004 | PCR, blood smear, culture | N.r. | N.r. | N.r. | [30] | ||
| 3 | USA | 2007 | PCR (3/3) | Fever (3/3), headache (2/3), nausea and vomiting (2/3), myalgia (1/3), cough (1/3) | N.r. | All survived | 3/3 immunocompromised | [31] | |
| 1 | USA | 2009 | PCR | Fever, chills, myalgias, nausea and headache | Leukopenia, elevated liver enzymes | Survived | No cross-reactivity with E. chaffeensis | [32] | |
| 7 | USA | 2009 | PCR (7/7) | Fever (7/7), headache (3/7), cough (2/7), malaise (2/7), rash (1/7), arthralgias (1/7), weakness (1/7), nausea (1/7), dyspnea (1/7) | N.r. | All survived | 7/7 immunocompromised | [33] | |
| 1 | USA | 2013 | PCR, blood smear | Fever, fatigue, vomiting, diarrhea, petechial rash | Neutropenia, thrombocytopenia, elevated liver enzymes | Survived | E. ewingii infection through platelet transfusion, immunocompromised | [14] | |
| 1 | USA | 2014 | PCR, blood smear | Fever, cough, myalgia, fatigue, weakness, petechiae and bruising | Pancytopenia, elevated bilirubin, LDH and ferritin | Survived | Involvement of bone marrow | [34] | |
| 5 | USA | 2016 | PCR (5/5) | Fever (5/5), headache (2/5), nausea (2/5), malaise (1/5), rash, myalgia(1/5), arthralgia (1/5), vomiting (1/5), abdominal pain (1/5), diarrhea (1/5) | Leukopenia (4/5), thrombocytopenia (4/5), elevated liver enzymes (2/5) | 4/5 survived, 1/5 died of HE unrelated cause | [35]* | ||
| 1 | USA | 2017 | PCR, blood smear | Fever, chills, nausea, vomiting, pedal edema | Pancytopenia | Survived | Immunocompromised | [36] | |
| 10 | USA | 2019 | PCR (10/10) | N.r. | N.r. | 2/10 died, 8/10 survived | 7/10 immunocompromised | [37] | |
| E. ruminantium | 3 | South Africa | 2005 | PCR (3/3) | Encephalitis (2/3), 1/3 fever, headache, ataxia, progressive sleepiness | Leukocytosis and thrombocytosis (1/3) | All died | [38] | |
| Panola Mountain Ehrlichia | 1 | USA | 2008 | PCR | Neck pain | N.r. | Survived | [39] | |
| Ehrlichia sp. Wisconsin HM543745 | 4 | USA | 2011 | PCR (4/4), culture (1/4) | Fever (4/4), headache (4/4), malaise/fatigue (4/4), nausea and vomiting (1/4) | Lymphopenia (4/4), thrombocytopenia (3/4), elevated liver enzymes (3/4) | All survived | 2/4 immunocompromised | [13] |
| Candidatus Ehrlichia erythraense | 19 | China | 2023 | PCR (15/19), paired IgG-IFA serology (4/19) | 19/19 fever, rash, asthenia and anorexia, 15/19 myalgia | 6/19 leukopenia, thrombocytopenia, elevated liver enzymes, 18/19 increased CRP | All survived | [40] |
CRP, C-reactive protein; E. ewingii, Ehrlichia ewingii; E. ruminantium, Ehrlichia ruminantium; HE, human ehrlichiosis; IgG, immunoglobulin G; IFA, immunofluorescence assay; LDH, lactate dehydrogenase; N.r., none/not reported; PCR, polymerase chain reaction; Ref., reference; USA, United States of America.
* regarding [35]: this publication describes an additional five cases of human Ehrlichia ewingii infections. Those cases were not included in our analysis because of insufficient clinical data.