Correspondence

Rapidly Fatal Infection with Ehrlichia chaffeensis

N Engl J Med 1999; 341:763-764September 2, 1999

Article

To the Editor:

Human ehrlichial infections are increasingly being recognized as common tick-borne diseases in the United States. Clinical characteristics of ehrlichiosis include fever, headache, and malaise with leukopenia, thrombocytopenia, and elevated levels of hepatic aminotransferases.1 In rare instances, infection may result in multiple organ failure and death, particularly in immunosuppressed patients.2 Despite the potential severity of disease, death is uncommon in normal human hosts. We report two cases of rapidly fatal Ehrlichia chaffeensis infection in patients who presented to our institution in early June.

A 22-year-old man was hospitalized with hypotension after a one-week illness characterized by fever, headache, myalgias, and diarrhea following exposure to a tick during military exercises. Outpatient treatment had included ceftriaxone and erythromycin, with doxycycline added immediately before transfer to our institution because of progressive hypoxemia. Within 50 hours, generalized seizures, adrenal insufficiency, acute lung injury, disseminated intravascular coagulation, and multiple-organ failure resulted in death, despite aggressive resuscitation measures.

A 38-year-old man with AIDS, hepatitis B, and hepatitis C presented to our emergency department with fever, headache, diarrhea, and dysuria one week after exposure to a tick. Cephalexin had been prescribed for a suspected urinary tract infection. In the hospital, he had hypotension, generalized seizures, severe metabolic acidosis, acute lung injury, and multiple-organ failure and died within 24 hours, despite appropriate antimicrobial therapy.

Peripheral-blood specimens from both patients demonstrated intraleukocytic morulae (Figure 1Figure 1 Ehrlichia chaffeensis Morulae in Peripheral-Blood Specimens (Wright's Stain, ×1250).) and, as shown by polymerase chain reaction, were positive for E. chaffeensis 16S ribosomal DNA (methods described previously).3

Human ehrlichial disease falls along a spectrum of severity, ranging from asymptomatic (in as many as 67 percent of patients) to fulminant and fatal.4 Normal hosts rarely succumb to ehrlichial infections, particularly when they are younger than 60 years and when appropriate antimicrobial therapy, such as doxycycline, is administered early.5 Because the symptoms are nonspecific, tick-borne infections may not be considered.

It is unclear whether our experience is a result of heightened recognition, increased exposure and environmental encroachment (e.g., through military training), infectious burden, or an unusually virulent infection. Regardless, for rapid initiation of appropriate empirical therapy — before diagnostic confirmation — it is imperative to recognize early the symptoms and laboratory abnormalities common to rickettsial infections in high-risk patients from endemic areas, to prevent the morbid cascade of organ failure.

Greg S. Martin, M.D.
Brian W. Christman, M.D.
Steven M. Standaert, M.D.
Vanderbilt University Medical Center, Nashville, TN 37232-2650

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Citing Articles (8)

Citing Articles

1. 1

   Juan P. Olano, Gary Wen, Hui-Min Feng, Jere W. McBride, David H. Walker. (2004) Histologic, Serologic, and Molecular Analysis of Persistent Ehrlichiosis in a Murine Model. The American Journal of Pathology 165:3, 997-1006
   CrossRef

2. 2

   S. A. Springer, F. L. Altice. (2003) Human Immunodeficiency Virus Infection with Human Granulocytic Ehrlichiosis Complicated by Symptomatic Lactic Acidosis. Clinical Infectious Diseases 36:12, e162-e164
   CrossRef

3. 3

   Daryl J. Kelly, Allen L. Richards, Joseph Temenak, Daniel Strickman, Gregory A. Dasch. (2002) The Past and Present Threat of Rickettsial Diseases to Military Medicine and International Public Health. Clinical Infectious Diseases 34:S4, S145-S169
   CrossRef

4. 4

   Christopher D. Paddock, Scott M. Folk, G. Merrill Shore, Linda J. Machado, Mark M. Huycke, Leonard N. Slater, Allison M. Liddell, Richard S. Buller, Gregory A. Storch, Thomas P. Monson, David Rimland, John W. Sumner, Joseph Singleton, Karen C. Bloch, Yi‐Wei Tang, Steven M. Standaert, James E. Childs. (2001) Infections with Ehrlichia chaffeensis and Ehrlichia ewingii in Persons Coinfected with Human Immunodeficiency Virus. Clinical Infectious Diseases 33:9, 1586-1594
   CrossRef

5. 5

   Joshua Schiffman, Mohammad Haq, Fortunato Procopio, Edwin N. Forman. (2001) Ehrlichiosis Infection in a 5-Year-Old Boy With Neutropenia, Anemia, Thrombocytopenia, and Hepatosplenomegaly. Journal of Pediatric Hematology/Oncology 23:5, 324-327
   CrossRef

6. 6

   Henkie P. Tan, J. Stephen Dumler, Warren R. Maley, Andrew S. Klein, James F. Burdick, F. Fred Poordad, Paul J. Thuluvath, Jay S. Markowitz. (2001) HUMAN MONOCYTIC EHRLICHIOSIS: AN EMERGING PATHOGEN IN TRANSPLANTATION. Transplantation 71:11, 1678-1680
   CrossRef

7. 7

   J Stephen Dumler, David H Walker. (2001) Tick-borne ehrlichioses. The Lancet Infectious Diseases 1, 21-28
   CrossRef

8. 8

   Timothy R. Peters, Kathryn M. Edwards, Steven M. Standaert. (2000) SEVERE EHRLICHIOSIS IN AN ADOLESCENT TAKING TRIMETHOPRIM-SULFAMETHOXAZOLE. The Pediatric Infectious Disease Journal 19:2, 170
   CrossRef