Rhodococcus equi Clinical Presentation

  • Author: Indira Kedlaya, MD; Chief Editor: Burke A Cunha, MD   more...
 
Updated: Nov 21, 2011
 

History

The onset of R equi infections is generally insidious, and presenting symptoms vary according to the infection site. Symptoms in immunocompetent patients do not differ from those in immunocompromised patients. In R equi infections secondary to trauma, such as endophthalmitis, septic arthritis, and traumatic meningitis, symptoms may present within 24 hours of the trauma.

  • Pulmonary R equi infections include the following:
    • Fever and cough (>80% of patients with pulmonary R equi infections)
    • Malaise
    • Chest pain
    • Dyspnea
    • Hemoptysis
    • Weight loss
    • Possible chronic or relapsing course
    • Possible community-acquired pneumonia that fails to respond to empirical treatment
  • Other presentations of R equi infection include lymphadenopathy, eye drainage and pain, joint pain, altered level of consciousness, bloody diarrhea, and fever of unknown origin. Anemia caused by colonic polyps infected with R equi has also been reported.[10]
  • R equi infections can also be acquired nosocomially. Poststernotomy infection after coronary artery bypass grafting has been reported twice, and postneurosurgical brain abscess has been reported once (although not officially). R equi infection after placement of a ventriculoperitoneal (VP) shunt has also been reported twice.
  • Epidemiological history is important. Exposure to soil contaminated with manure is the most likely route of both animal and human infection. Exposure is usually inhalational, but infections via the oral route (due to ingestion of soil or food) or via direct inoculation due to trauma have also been well described. A history of animal exposure may be absent.
    • R equi has been found in bovine, porcine, and equine fecal flora and grows best at summer temperatures. Isolation of the organism from the air on horse farms rises with ambient temperature and is highest on dry windy days.
    • In addition, a history concerning any preexisting immunocompromising conditions should be obtained. These include malignancy, recent chemotherapy, solid organ or bone marrow transplantation, diabetes mellitus, alcoholism, and immunosuppressive medications. History pertaining to sexual practices and injection drug use is also important.
Next

Physical

Physical findings depend on the site of infection and include the following:

  • Fever
  • Tachypnea, crackles, and other common physical findings of pneumonia
  • Lymphadenopathy
  • Septic arthritis
  • Corneal laceration, hyperemia, decreased visual acuity, evidence of anterior chamber involvement (eg, hypopyon)
  • Findings of meningitis
  • Soft-tissue masses, induration, fluctuance in localized infections consistent with abscesses, examination of postoperative sites
Previous
Next

Causes

  • About 80-90% of patients with R equi infection are immunocompromised. About 50-60% of the patients have HIV infection, 15-20% have hematopoietic and other malignancies, and 10% are transplant recipients. Infections have been reported in the following immunocompromised conditions:
    • AIDS: In a study by Capdevila et al (1997) of 78 patients infected with HIV who developed R equi pneumonia, 71 patients met criteria for AIDS and at least 60 of 78 patients had CD4+ counts of less than 200 cells/µL.[9] In another study, by Donisi et al (1996), involving R equi pneumonia in patients infected with HIV, the mean CD4+ count was 47.7 cells/µL.[11]
    • Lymphoma, leukemia, and other malignancies: This includes immunosuppression associated with chemotherapy, such as neutropenia. Neutropenic fever due to R equi bacteremia has been described.
    • Transplantation, including solid organ (kidney, liver, heart) and bone marrow
    • Chronic renal insufficiency and patients with end-stage renal disease on peritoneal dialysis
    • Alcoholism
    • Diabetes mellitus
    • Patients receiving immunosuppressive therapy, including corticosteroids
  • R equi infections can also occur in immunocompetent persons. Infections in these patients include pneumonia, endophthalmitis, septic arthritis, traumatic meningitis, brain abscess, fever of unknown origin, lymphangitis, and lymphadenitis. A history of trauma should be obtained because about 50% of R equi infections described in immunocompetent patients are due to trauma.
Previous
Proceed to Differential Diagnoses
 
 
Contributor Information and Disclosures
Author

Indira Kedlaya, MD  Provider, Sunshine Medical Group, PLLC

Indira Kedlaya, MD is a member of the following medical societies: American College of Physicians-American Society of Internal Medicine

Disclosure: Nothing to disclose.

Coauthor(s)

Michael Ing, MD  Chief, Section of Infectious Disease, JL Pettis Memorial VA Medical Center, Assistant Professor, Department of Internal Medicine, Loma Linda University School of Medicine

Michael Ing, MD is a member of the following medical societies: Alpha Omega Alpha, American Academy of HIV Medicine, American College of Physicians-American Society of Internal Medicine, American Society for Microbiology, American Society of Tropical Medicine and Hygiene, HIV Medicine Association of America, Infectious Diseases Society of America, International AIDS Society, Royal Society of Tropical Medicine and Hygiene, and Society for Healthcare Epidemiology of America

Disclosure: Nothing to disclose.

Specialty Editor Board

Larry I Lutwick, MD  Professor of Medicine, State University of New York Downstate Medical School; Director, Infectious Diseases, Veterans Affairs New York Harbor Health Care System, Brooklyn Campus

Larry I Lutwick, MD is a member of the following medical societies: American College of Physicians and Infectious Diseases Society of America

Disclosure: Nothing to disclose.

Francisco Talavera, PharmD, PhD  Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Medscape Salary Employment

Aaron Glatt, MD  Professor of Clinical Medicine, New York Medical College; President and CEO, Former Chief Medical Officer, Departments of Medicine and Infectious Diseases, St Joseph Hospital (formerly New Island Hospital)

Aaron Glatt, MD is a member of the following medical societies: American College of Chest Physicians, American College of Physician Executives, American College of Physicians, American College of Physicians-American Society of Internal Medicine, American Medical Association, American Society for Microbiology, American Thoracic Society, American Venereal Disease Association, Infectious Diseases Society of America, International AIDS Society, and Society for Healthcare Epidemiology of America

Disclosure: Nothing to disclose.

Eleftherios Mylonakis, MD  Clinical and Research Fellow, Department of Internal Medicine, Division of Infectious Diseases, Massachusetts General Hospital

Eleftherios Mylonakis, MD is a member of the following medical societies: American Association for the Advancement of Science, American College of Physicians, American Society for Microbiology, and Infectious Diseases Society of America

Disclosure: Nothing to disclose.

Chief Editor

Burke A Cunha, MD  Professor of Medicine, State University of New York School of Medicine at Stony Brook; Chief, Infectious Disease Division, Winthrop-University Hospital

Burke A Cunha, MD is a member of the following medical societies: American College of Chest Physicians, American College of Physicians, and Infectious Diseases Society of America

Disclosure: Nothing to disclose.

References

  1. Giguère S, Cohen ND, Keith Chaffin M, Hines SA, Hondalus MK, Prescott JF, et al. Rhodococcus equi: Clinical Manifestations, Virulence, and Immunity. J Vet Intern Med. Nov 2011;25(6):1221-30. [Medline].

  2. Giguère S, Cohen ND, Keith Chaffin M, Slovis NM, Hondalus MK, Hines SA, et al. Diagnosis, Treatment, Control, and Prevention of Infections Caused by Rhodococcus equi in Foals. J Vet Intern Med. Nov 2011;25(6):1209-20. [Medline].

  3. Verville TD, Huycke MM, Greenfield RA, et al. Rhodococcus equi infections of humans. 12 cases and a review of the literature. Medicine (Baltimore). May 1994;73(3):119-32. [Medline].

  4. Makrai L, Takai S, Tamura M, et al. Characterization of virulence plasmid types in Rhodococcus equi isolates from foals, pigs, humans and soil in Hungary. Vet Microbiol. Sep 24 2002;88(4):377-84. [Medline].

  5. Takai S, Tharavichitkul P, Takarn P, et al. Molecular epidemiology of Rhodococcus equi of intermediate virulence isolated from patients with and without acquired immune deficiency syndrome in Chiang Mai, Thailand. J Infect Dis. Dec 1 2003;188(11):1717-23. [Medline].

  6. Cornish N, Washington JA. Rhodococcus equi infections: clinical features and laboratory diagnosis. Curr Clin Top Infect Dis. 1999;19:198-215. [Medline].

  7. Harvey RL, Sunstrum JC. Rhodococcus equi infection in patients with and without human immunodeficiency virus infection. Rev Infect Dis. Jan-Feb 1991;13(1):139-45. [Medline].

  8. Vladusic I, Krajinovic V, Begovac J. [Long term survival after Rhodococcus equi pneumonia in a patient with human immunodeficiency virus infection in the era of highly active antiretroviral therapy: case report and review]. Acta Med Croatica. Jun 2006;60(3):259-63. [Medline].

  9. Capdevila JA, Bujan S, Gavalda J, et al. Rhodococcus equi pneumonia in patients infected with the human immunodeficiency virus. Report of 2 cases and review of the literature. Scand J Infect Dis. 1997;29(6):535-41. [Medline].

  10. Talanin NY, Donabedian H, Kaw M, et al. Colonic polyps and disseminated infection associated with Rhodococcus equi in a patient with AIDS. Clin Infect Dis. May 1998;26(5):1241-2. [Medline].

  11. Donisi A, Suardi MG, Casari S, et al. Rhodococcus equi infection in HIV-infected patients. AIDS. Apr 1996;10(4):359-62. [Medline].

  12. Munoz P, Palomo J, Guinea J, et al. Relapsing Rhodococcus equi infection in a heart transplant recipient successfully treated with long-term linezolid. Diagn Microbiol Infect Dis. Feb 2008;60(2):197-9. [Medline].

  13. Scotton PG, Tonon E, Giobbia M, et al. Rhodococcus equi nosocomial meningitis cured by levofloxacin and shunt removal. Clin Infect Dis. Jan 2000;30(1):223-4. [Medline].

  14. Gabriels P, Joosen H, Put E, et al. Recurrent Rhodococcus equi infection with fatal outcome in an immunocompetent patient. Eur J Clin Microbiol Infect Dis. Jan 2006;25(1):46-8. [Medline].

  15. Giguère S, Jacks S, Roberts GD, et al. Retrospective comparison of azithromycin, clarithromycin, and erythromycin for the treatment of foals with Rhodococcus equi pneumonia. J Vet Intern Med. Jul-Aug 2004;18(4):568-73. [Medline].

  16. Bouchou K, Cathebras P, Dumollard JM, et al. Chronic osteitis due to Rhodococcus equi in an immunocompetent patient. Clin Infect Dis. Mar 1995;20(3):718-20. [Medline].

  17. Corne P, Rajeebally I, Jonquet O. Rhodococcus equi brain abscess in an immunocompetent patient. Scand J Infect Dis. 2002;34(4):300-2. [Medline].

  18. Cunha BA. Antibiotic Essentials. Physicians Press: Royal Oak, Mich; 2005.

  19. Cunha BA. Rhodococcus equi Pneumonia in AIDS Patient - A Commentary. Infect Dis Clin Pract. 1994;3:119-121.

  20. Drancourt M, Bonnet E, Gallais H, et al. Rhodococcus equi infection in patients with AIDS. J Infect. Mar 1992;24(2):123-31. [Medline].

  21. Ebersole LL, Paturzo JL. Endophthalmitis caused by Rhodococcus equi Prescott serotype 4. J Clin Microbiol. Jun 1988;26(6):1221-2. [Medline].

  22. Fierer J, Wolf P, Seed L, et al. Non-pulmonary Rhodococcus equi infections in patients with acquired immune deficiency syndrome (AIDS). J Clin Pathol. May 1987;40(5):556-8. [Medline].

  23. Germain. A propos d'une observation d'infection humaine a' corynebacterium equi. Med Mal Infect. 1975;5:294-97.

  24. Hillman D, Garretson B, Fiscella R. Rhodococcus equi endophthalmitis. Case report. Arch Ophthalmol. Jan 1989;107(1):20. [Medline].

  25. Jacks SS, Giguere S, Nguyen A. In vitro susceptibilities of Rhodococcus equi and other common equine pathogens to azithromycin, clarithromycin, and 20 other antimicrobials. Antimicrob Agents Chemother. May 2003;47(5):1742-5. [Medline].

  26. Johnson DH, Cunha BA. Rhodococcus equi pneumonia. Semin Respir Infect. Mar 1997;12(1):57-60. [Medline].

  27. Kedlaya I, Ing MB, Wong SS. Rhodococcus equi infections in immunocompetent hosts: case report and review. Clin Infect Dis. Feb 1 2001;32(3):E39-46. [Medline].

  28. Kwon KY, Colby TV. Rhodococcus equi pneumonia and pulmonary malakoplakia in acquired immunodeficiency syndrome. Pathologic features. Arch Pathol Lab Med. Jul 1994;118(7):744-8. [Medline].

  29. Lasky JA, Pulkingham N, Powers MA, et al. Rhodococcus equi causing human pulmonary infection: review of 29 cases. South Med J. Oct 1991;84(10):1217-20. [Medline].

  30. Legras A, Lemmens B, Dequin PF, et al. Tamponade due to Rhodococcus equi in acquired immunodeficiency syndrome. Chest. Oct 1994;106(4):1278-9. [Medline].

  31. Linares MJ, Lopez-Encuentra A, Perea S. Chronic pneumonia caused by Rhodococcus equi in a patient without impaired immunity. Eur Respir J. Jan 1997;10(1):248-50. [Medline].

  32. Moyer DV, Bayer AS. Progressive pulmonary infiltrates and positive blood cultures for weakly acid-fast, gram-positive rods in a 76-year-old woman. Chest. Jul 1993;104(1):259-61. [Medline].

  33. Munoz P, Burillo A, Palomo J, et al. Rhodococcus equi infection in transplant recipients: case report and review of the literature. Transplantation. Feb 15 1998;65(3):449-53. [Medline].

  34. Muntaner L, Leyes M, Payeras A, et al. Radiologic features of Rhodococcus equi pneumonia in AIDS. Eur J Radiol. Jan 1997;24(1):66-70. [Medline].

  35. Nordmann P, Kerestedjian JJ, Ronco E. Therapy of Rhodococcus equi disseminated infections in nude mice. Antimicrob Agents Chemother. Jun 1992;36(6):1244-8. [Medline].

  36. Nordmann P, Nicolas MH, Gutmann L. Penicillin-binding proteins of Rhodococcus equi: potential role in resistance to imipenem. Antimicrob Agents Chemother. Jul 1993;37(7):1406-9. [Medline].

  37. Nordmann P, Ronco E. In-vitro antimicrobial susceptibility of Rhodococcus equi. J Antimicrob Chemother. Apr 1992;29(4):383-93. [Medline].

  38. Schilz RJ, Kavuru MS, Hall G, et al. Spontaneous resolution of rhodococcal pulmonary infection in a liver transplant recipient. South Med J. Aug 1997;90(8):851-4. [Medline].

  39. Scott MA, Graham BS, Verrall R, et al. Rhodococcus equi--an increasingly recognized opportunistic pathogen. Report of 12 cases and review of 65 cases in the literature. Am J Clin Pathol. May 1995;103(5):649-55. [Medline].

  40. Sigler E, Miskin A, Shtlarid M, et al. Fever of unknown origin and anemia with Rhodococcus equi infection in an immunocompetent patient. Am J Med. May 1998;104(5):510. [Medline].

  41. Sladek GG, Frame JN. Rhodococcus equi causing bacteremia in an adult with acute leukemia. South Med J. Feb 1993;86(2):244-6. [Medline].

  42. Takai S, Fukunaga N, Ochiai S, et al. Identification of intermediately virulent Rhodococcus equi isolates from pigs. J Clin Microbiol. Apr 1996;34(4):1034-7. [Medline].

  43. Takai S, Sasaki Y, Ikeda T, et al. Virulence of Rhodococcus equi isolates from patients with and without AIDS. J Clin Microbiol. Feb 1994;32(2):457-60. [Medline].

  44. Thomsen F, Henriques R, Magnusson M. Corynebacterium equi Magnusson isolated from a tuberculoid lesion in a child with adenitis colli. Dan Med Bull. May 1968;15(5):135-8. [Medline].

  45. Tunger A, Ozkan F, Vardar F, et al. Purulent meningitis due to Rhodococcus equi. A case of posttraumatic infection. APMIS. Sep 1997;105(9):705-7. [Medline].

  46. Walsh RD, Cunha BA. Rhodococcus equi: fatal pneumonia in a patient without AIDS. Heart Lung. Nov-Dec 1994;23(6):519-20. [Medline].

  47. Weinstock DM, Brown AE. Rhodococcus equi: an emerging pathogen. Clin Infect Dis. May 15 2002;34(10):1379-85. [Medline].

 
Previous
Next
 
Chest radiograph of a patient with Rhodococcus equi infection showing multiple nodular infiltrates.
Chest radiograph of a patient with Rhodococcus equi infection demonstrating cavitation of pulmonary nodules.
Chest CT scan of a patient with Rhodococcus equi infection demonstrating nodular infiltrates.
 
 
 
All material on this website is protected by copyright, Copyright © 1994-2012 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.

DISCLAIMER: The content of this Website is not influenced by sponsors. The site is designed primarily for use by qualified physicians and other medical professionals. The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. The information provided here is for educational and informational purposes only. In no way should it be considered as offering medical advice. Please check with a physician if you suspect you are ill.