Fibrin ring granulomas in Rickettsia typhi infection

Restrepo, Marcos I.; Vasquez, E. Martin; Echeverri, Carolina; Fiebelkorn, Kristin R.; Anstead, Gregory M.

doi:10.1016/j.diagmicrobio.2009.10.019

« Previous Next »Diagnostic Microbiology & Infectious Disease
Volume 66, Issue 3 , Pages 322-325, March 2010

Fibrin ring granulomas in Rickettsia typhi infection

Marcos I. Restrepo
- Veterans Evidence Research Dissemination and Implementation Center (VERDICT), South Texas Veterans Health Care System, San Antonio, TX 78229, USA
- Pulmonary Division, Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
E. Martin Vasquez
- Hospital Pablo Tobon Uribe, Calle 78 B No. 69-240, Medellín, Colombia—Suramérica
Carolina Echeverri
- Hospital Pablo Tobon Uribe, Calle 78 B No. 69-240, Medellín, Colombia—Suramérica
Kristin R. Fiebelkorn
- Department of Pathology, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
Gregory M. Anstead
- Department of Medicine, South Texas Veterans Healthcare System, San Antonio, TX 78229, USA
- Division of Infectious Diseases, Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA
- Corresponding author. Division of Infectious Diseases, Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229-3900, USA. Tel.: +1-210-567-4666; fax: +1-210-567-4670.

Received 29 April 2009; accepted 27 October 2009. published online 13 January 2010.

Abstract

We describe a 71-year-old man hospitalized for fever and productive cough. Laboratory investigation showed anemia, thrombocytopenia, elevated transaminases, hyponatremia, and hypoalbuminemia. Computerized tomography of the abdomen, thorax, and sinuses, echocardiography, and a gallium scan did not reveal the source of the fever. The patient remained febrile despite courses of piperacillin–tazobactam/azithromycin and ceftriaxone/vancomycin. A bone marrow biopsy showed fibrin ring granulomas, and 2 rickettsial serologic panels were positive for Rickettsia typhi infection and negative for Q fever. The patient was given doxycycline, and the fever resolved within 48 h. We propose that fibrin ring granulomas also occur in murine typhus.

Keywords: Rickettsia typhi, Murine typhus, Fever of unknown origin, Fibrin ring granuloma