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Blanton LS. Murine Typhus: A Review of a Reemerging Flea-Borne Rickettsiosis with Potential for Neurologic Manifestations and Sequalae. Infect Dis Rep 2023; 15:700-716. [PMID: 37987401 PMCID: PMC10660532 DOI: 10.3390/idr15060063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 10/24/2023] [Accepted: 10/24/2023] [Indexed: 11/22/2023] Open
Abstract
Murine typhus is an acute febrile illness caused by Rickettsia typhi, an obligately intracellular Gram-negative coccobacillus. Rats (Rattus species) and their fleas (Xenopsylla cheopis) serve as the reservoir and vector of R. typhi, respectively. Humans become infected when R. typhi-infected flea feces are rubbed into flea bite wounds or onto mucous membranes. The disease is endemic throughout much of the world, especially in tropical and subtropical seaboard regions where rats are common. Murine typhus is reemerging as an important cause of febrile illness in Texas and Southern California, where an alternate transmission cycle likely involves opossums (Didelphis virginiana) and cat fleas (Ctenocephalides felis). Although primarily an undifferentiated febrile illness, a range of neurologic manifestations may occur, especially when treatment is delayed. Serology is the mainstay of diagnostic testing, but confirmation usually requires demonstrating seroconversion or a fourfold increase in antibody titer from acute- and convalescent-phase sera (antibodies are seldom detectable in the first week of illness). Thus, early empiric treatment with doxycycline, the drug of choice, is imperative. The purpose of this review is to highlight murine typhus as an important emerging and reemerging infectious disease, review its neurologic manifestations, and discuss areas in need of further study.
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Affiliation(s)
- Lucas S Blanton
- Department Internal Medicine, Division of Infectious Diseases, University of Texas Medical Branch, Galveston, TX 77555, USA
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2
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Lokida D, Hadi U, Lau CY, Kosasih H, Liang CJ, Rusli M, Sudarmono P, Lukman N, Laras K, Asdie RH, Murniati D, Utama IMS, Mubin RH, Karyana M, Gasem MH, Alisjahbana B. Underdiagnoses of Rickettsia in patients hospitalized with acute fever in Indonesia: observational study results. BMC Infect Dis 2020; 20:364. [PMID: 32448167 PMCID: PMC7245627 DOI: 10.1186/s12879-020-05057-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2020] [Accepted: 04/28/2020] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Reports of human rickettsial infection in Indonesia are limited. This study sought to characterize the epidemiology of human rickettsioses amongst patients hospitalized with fever at 8 tertiary hospitals in Indonesia. METHODS Acute and convalescent blood from 975 hospitalized non-dengue patients was tested for Rickettsia IgM and IgG by ELISA. Specimens from cases with seroconversion or increasing IgM and/or IgG titers were tested for Rickettsia IgM and IgG by IFA and Rickettsia genomes using primers for Rickettsia (R.) sp, R. typhi, and Orientia tsutsugamushi. Testing was performed retrospectively on stored specimens; results did not inform patient management. RESULTS R. typhi, R. rickettsii, and O. tsutsugamushi IgG antibodies were identified in 269/872 (30.8%), 36/634 (5.7%), and 19/504 (3.8%) of samples, respectively. For the 103/975 (10.6%) non-dengue patients diagnosed with acute rickettsial infection, presenting symptoms included nausea (72%), headache (69%), vomiting (43%), lethargy (33%), anorexia (32%), arthralgia (30%), myalgia (28%), chills (28%), epigastric pain (28%), and rash (17%). No acute rickettsioses cases were suspected during hospitalization. Discharge diagnoses included typhoid fever (44), dengue fever (20), respiratory infections (7), leptospirosis (6), unknown fever (6), sepsis (5), hepatobiliary infections (3), UTI (3), and others (9). Fatalities occurred in 7 (6.8%) patients, mostly with co-morbidities. CONCLUSIONS Rickettsial infections are consistently misdiagnosed, often as leptospirosis, dengue, or Salmonella typhi infection. Clinicians should include rickettsioses in their differential diagnosis of fever to guide empiric management; laboratories should support evaluation for rickettsial etiologies; and public policy should be implemented to reduce burden of disease.
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Affiliation(s)
- Dewi Lokida
- Tangerang District Hospital, Tangerang, Indonesia
- Indonesia Research Partnership on Infectious Disease (INA-RESPOND), Badan Litbangkes, Building 4, 5th floor, Jl Percetakan Negara no 29, Jakarta, 10560, Indonesia
| | - Usman Hadi
- Dr. Soetomo Academic General Hospital - Faculty of Medicine Universitas Airlangga, Surabaya, Indonesia
| | - Chuen-Yen Lau
- National Institute of Allergy and Infectious Disease (NIAID), National Institutes of Health, Bethesda, MD, USA
| | - Herman Kosasih
- Indonesia Research Partnership on Infectious Disease (INA-RESPOND), Badan Litbangkes, Building 4, 5th floor, Jl Percetakan Negara no 29, Jakarta, 10560, Indonesia.
| | - C Jason Liang
- National Institute of Allergy and Infectious Disease (NIAID), National Institutes of Health, Bethesda, MD, USA
| | - Musofa Rusli
- Dr. Soetomo Academic General Hospital - Faculty of Medicine Universitas Airlangga, Surabaya, Indonesia
| | | | - Nurhayati Lukman
- Indonesia Research Partnership on Infectious Disease (INA-RESPOND), Badan Litbangkes, Building 4, 5th floor, Jl Percetakan Negara no 29, Jakarta, 10560, Indonesia
| | - Kanti Laras
- Indonesia Research Partnership on Infectious Disease (INA-RESPOND), Badan Litbangkes, Building 4, 5th floor, Jl Percetakan Negara no 29, Jakarta, 10560, Indonesia
| | | | | | | | | | - Muhammad Karyana
- Indonesia Research Partnership on Infectious Disease (INA-RESPOND), Badan Litbangkes, Building 4, 5th floor, Jl Percetakan Negara no 29, Jakarta, 10560, Indonesia
- National Institute of Health Research and Development (NIHRD), Ministry of Health Republic of Indonesia, Jakarta, Indonesia
| | | | - Bachti Alisjahbana
- Hasan Sadikin Hospital - Faculty of Medicine Universitas Padjadjaran, Bandung, Indonesia
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3
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Anstead GM. History, Rats, Fleas, and Opossums: The Ascendency of Flea-Borne Typhus in the United States, 1910-1944. Trop Med Infect Dis 2020; 5:E37. [PMID: 32121541 PMCID: PMC7157735 DOI: 10.3390/tropicalmed5010037] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 02/07/2020] [Accepted: 02/10/2020] [Indexed: 12/03/2022] Open
Abstract
Flea-borne typhus, due to Rickettsia typhi and Rickettsia felis, is an infection causing fever, headache, rash, hepatitis, thrombocytopenia, and diverse organ manifestations. Although most cases are self-limited, 26%-28% have complications and up to one-third require intensive care. Flea-borne typhus was recognized as an illness similar to epidemic typhus, but having a milder course, in the Southeastern United States and TX from 1913 into the 1920s. Kenneth Maxcy of the US Public Health Service (USPHS) first described the illness in detail and proposed a rodent reservoir and an arthropod vector. Other investigators of the USPHS (Eugene Dyer, Adolph Rumreich, Lucius Badger, Elmer Ceder, William Workman, and George Brigham) determined that the brown and black rats were reservoirs and various species of fleas, especially the Oriental rat flea, were the vectors. The disease was recognized as a health concern in the Southern United States in the 1920s and an increasing number of cases were observed in the 1930s and 1940s, with about 42,000 cases reported between 1931-1946. Attempts to control the disease in the 1930s by fumigation and rat proofing and extermination were unsuccessful. The dramatic increase in the number of cases from 1930 through 1944 was due to: the diversification of Southern agriculture away from cotton; the displacement of the smaller black rat by the larger brown rat in many areas; poor housing conditions during the Great Depression and World War II; and shortages of effective rodenticides and insecticides during World War II.
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Affiliation(s)
- Gregory M. Anstead
- Medical Service, South Texas Veterans Health Care System, San Antonio, TX 78229, USA; ; Tel.: +210-567-4666; Fax: +210-567-4670
- Department of Medicine, University of Texas Health Science Center at San Antonio, San Antonio, TX 78229, USA
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4
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Biggs HM, Behravesh CB, Bradley KK, Dahlgren FS, Drexler NA, Dumler JS, Folk SM, Kato CY, Lash RR, Levin ML, Massung RF, Nadelman RB, Nicholson WL, Paddock CD, Pritt BS, Traeger MS. Diagnosis and Management of Tickborne Rickettsial Diseases: Rocky Mountain Spotted Fever and Other Spotted Fever Group Rickettsioses, Ehrlichioses, and Anaplasmosis - United States. MMWR Recomm Rep 2016; 65:1-44. [PMID: 27172113 DOI: 10.15585/mmwr.rr6502a1] [Citation(s) in RCA: 311] [Impact Index Per Article: 38.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022] Open
Abstract
Tickborne rickettsial diseases continue to cause severe illness and death in otherwise healthy adults and children, despite the availability of low-cost, effective antibacterial therapy. Recognition early in the clinical course is critical because this is the period when antibacterial therapy is most effective. Early signs and symptoms of these illnesses are nonspecific or mimic other illnesses, which can make diagnosis challenging. Previously undescribed tickborne rickettsial diseases continue to be recognized, and since 2004, three additional agents have been described as causes of human disease in the United States: Rickettsia parkeri, Ehrlichia muris-like agent, and Rickettsia species 364D. This report updates the 2006 CDC recommendations on the diagnosis and management of tickborne rickettsial diseases in the United States and includes information on the practical aspects of epidemiology, clinical assessment, treatment, laboratory diagnosis, and prevention of tickborne rickettsial diseases. The CDC Rickettsial Zoonoses Branch, in consultation with external clinical and academic specialists and public health professionals, developed this report to assist health care providers and public health professionals to 1) recognize key epidemiologic features and clinical manifestations of tickborne rickettsial diseases, 2) recognize that doxycycline is the treatment of choice for suspected tickborne rickettsial diseases in adults and children, 3) understand that early empiric antibacterial therapy can prevent severe disease and death, 4) request the appropriate confirmatory diagnostic tests and understand their usefulness and limitations, and 5) report probable and confirmed cases of tickborne rickettsial diseases to public health authorities.
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Affiliation(s)
- Holly M Biggs
- National Center for Emerging and Zoonotic Infectious Diseases, CDC, Atlanta, Georgia
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5
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Teng GG, Chatham WW. Vasculitis related to viral and other microbial agents. Best Pract Res Clin Rheumatol 2015; 29:226-43. [PMID: 26362741 DOI: 10.1016/j.berh.2015.05.007] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2015] [Accepted: 05/08/2015] [Indexed: 12/11/2022]
Abstract
Vasculitis due to infection may occur as a consequence of the inflammation of vessel walls due to direct or contiguous infection, type II or immune complex-mediated reaction, cell-mediated hypersensitivity, or inflammation due to immune dysregulation triggered by bacterial toxin and/or superantigen production. As immunosuppressive therapy administered in the absence of antimicrobial therapy may increase morbidity and fail to effect the resolution of infection-associated vascular inflammation, it is important to consider infectious entities as potential inciting factors in vasculitis syndromes. The causality between infection and vasculitis has been established in hepatitis B-associated polyarteritis nodosa (HBV-PAN) and hepatitis C-associated (cryoglobulinemic) vasculitis (HCV-CV). The review summarizes the recent literature on the pathophysiological mechanisms and the approaches to the management of HBV-PAN and HCV-CV. Roles of other viral and microbial infections, which either manifest as vasculitic syndromes or are implicated in the pathogenesis of primary vasculitides, are also discussed.
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Affiliation(s)
- Gim Gee Teng
- Division of Rheumatology, University Medicine Cluster, National University Health System, Singapore; Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore and National University Health System, Singapore
| | - W Winn Chatham
- Division of Clinical Immunology and Rheumatology, University of Alabama at Birmingham, Birmingham, AL, USA.
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6
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Trout Fryxell RT, Steelman CD, Szalanski AL, Billingsley PM, Williamson PC. Molecular Detection of Rickettsia Species Within Ticks (Acari: Ixodidae) Collected from Arkansas United States. JOURNAL OF MEDICAL ENTOMOLOGY 2015; 52:500-508. [PMID: 26334827 DOI: 10.1093/jme/tjv027] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 02/24/2015] [Indexed: 06/05/2023]
Abstract
Rocky Mountain spotted fever (RMSF), caused by the etiological agent Rickettsia rickettsii, is the most severe and frequently reported rickettsial illness in the United States, and is commonly diagnosed throughout the southeast. With the discoveries of Rickettsia parkeri and other spotted fever group rickettsiae (SFGR) in ticks, it remains inconclusive if the cases reported as RMSF are truly caused by R. rickettsii or other SFGR. Arkansas reports one of the highest incidence rates of RMSF in the country; consequently, to identify the rickettsiae in Arkansas, 1,731 ticks, 250 white-tailed deer, and 189 canines were screened by polymerase chain reaction (PCR) for the rickettsial genes gltA, rompB, and ompA. None of the white-tailed deer were positive, while two of the canines (1.1%) and 502 (29.0%) of the ticks were PCR positive. Five different tick species were PCR positive: 244 (37%) Amblyomma americanum L., 130 (38%) Ixodes scapularis Say, 65 (39%) Amblyomma maculatum (Koch), 30 (9%) Rhipicephalus sanguineus Latreille, 7 (4%) Dermacentor variabilis Say, and 26 (44%) unidentified Amblyomma ticks. None of the sequenced products were homologous to R. rickettsii. The most common Rickettsia via rompB amplification was Rickettsia montanensis and nonpathogenic Candidatus Rickettsia amblyommii, whereas with ompA amplification the most common Rickettsia was Ca. R. amblyommii. Many tick specimens collected in northwest Arkansas were PCR positive and these were commonly A. americanum harboring Ca. R. amblyommii, a currently nonpathogenic Rickettsia. Data reported here indicate that pathogenic R. rickettsii was absent from these ticks and suggest by extension that other SFGR are likely the causative agents for Arkansas diagnosed RMSF cases.
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Affiliation(s)
- R T Trout Fryxell
- Department of Entomology and Plant Pathology, University of Tennessee, 370 Plant Biotechnology Bldg., 2505 E J Chapman Dr., Knoxville, TN 37996-4560.
| | - C D Steelman
- Department of Entomology, University of Arkansas, Fayetteville Arkansas
| | - A L Szalanski
- Department of Entomology, University of Arkansas, Fayetteville Arkansas
| | - P M Billingsley
- Department of Forensic and Investigative Genetics, University of North Texas Health Science Center, Ft. Worth, Texas
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7
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Paddock CD, Denison AM, Lash RR, Liu L, Bollweg BC, Dahlgren FS, Kanamura CT, Angerami RN, Pereira dos Santos FC, Brasil Martines R, Karpathy SE. Phylogeography of Rickettsia rickettsii genotypes associated with fatal Rocky Mountain spotted fever. Am J Trop Med Hyg 2014; 91:589-97. [PMID: 24957541 DOI: 10.4269/ajtmh.14-0146] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Rocky Mountain spotted fever (RMSF), a tick-borne zoonosis caused by Rickettsia rickettsii, is among the deadliest of all infectious diseases. To identify the distribution of various genotypes of R. rickettsii associated with fatal RMSF, we applied molecular typing methods to samples of DNA extracted from formalin-fixed, paraffin-embedded tissue specimens obtained at autopsy from 103 case-patients from seven countries who died of RMSF. Complete sequences of one or more intergenic regions were amplified from tissues of 30 (29%) case-patients and revealed a distribution of genotypes consisting of four distinct clades, including the Hlp clade, regarded previously as a non-pathogenic strain of R. rickettsii. Distinct phylogeographic patterns were identified when composite case-patient and reference strain data were mapped to the state and country of origin. The phylogeography of R. rickettsii is likely determined by ecological and environmental factors that exist independently of the distribution of a particular tick vector.
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Affiliation(s)
- Christopher D Paddock
- Infectious Diseases Pathology Branch and Rickettsial Zoonoses Branch, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Núcleo de Anatomica Patológia, Centro de Patologia do Instituto Adolfo Lutz, São Paulo, Brazil; Departamento de Vigilância em Saúde, Secretaria Municipal de Saúde de Campinas, São Paulo, Brazil
| | - Amy M Denison
- Infectious Diseases Pathology Branch and Rickettsial Zoonoses Branch, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Núcleo de Anatomica Patológia, Centro de Patologia do Instituto Adolfo Lutz, São Paulo, Brazil; Departamento de Vigilância em Saúde, Secretaria Municipal de Saúde de Campinas, São Paulo, Brazil
| | - R Ryan Lash
- Infectious Diseases Pathology Branch and Rickettsial Zoonoses Branch, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Núcleo de Anatomica Patológia, Centro de Patologia do Instituto Adolfo Lutz, São Paulo, Brazil; Departamento de Vigilância em Saúde, Secretaria Municipal de Saúde de Campinas, São Paulo, Brazil
| | - Lindy Liu
- Infectious Diseases Pathology Branch and Rickettsial Zoonoses Branch, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Núcleo de Anatomica Patológia, Centro de Patologia do Instituto Adolfo Lutz, São Paulo, Brazil; Departamento de Vigilância em Saúde, Secretaria Municipal de Saúde de Campinas, São Paulo, Brazil
| | - Brigid C Bollweg
- Infectious Diseases Pathology Branch and Rickettsial Zoonoses Branch, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Núcleo de Anatomica Patológia, Centro de Patologia do Instituto Adolfo Lutz, São Paulo, Brazil; Departamento de Vigilância em Saúde, Secretaria Municipal de Saúde de Campinas, São Paulo, Brazil
| | - F Scott Dahlgren
- Infectious Diseases Pathology Branch and Rickettsial Zoonoses Branch, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Núcleo de Anatomica Patológia, Centro de Patologia do Instituto Adolfo Lutz, São Paulo, Brazil; Departamento de Vigilância em Saúde, Secretaria Municipal de Saúde de Campinas, São Paulo, Brazil
| | - Cristina T Kanamura
- Infectious Diseases Pathology Branch and Rickettsial Zoonoses Branch, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Núcleo de Anatomica Patológia, Centro de Patologia do Instituto Adolfo Lutz, São Paulo, Brazil; Departamento de Vigilância em Saúde, Secretaria Municipal de Saúde de Campinas, São Paulo, Brazil
| | - Rodrigo N Angerami
- Infectious Diseases Pathology Branch and Rickettsial Zoonoses Branch, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Núcleo de Anatomica Patológia, Centro de Patologia do Instituto Adolfo Lutz, São Paulo, Brazil; Departamento de Vigilância em Saúde, Secretaria Municipal de Saúde de Campinas, São Paulo, Brazil
| | - Fabiana C Pereira dos Santos
- Infectious Diseases Pathology Branch and Rickettsial Zoonoses Branch, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Núcleo de Anatomica Patológia, Centro de Patologia do Instituto Adolfo Lutz, São Paulo, Brazil; Departamento de Vigilância em Saúde, Secretaria Municipal de Saúde de Campinas, São Paulo, Brazil
| | - Roosecelis Brasil Martines
- Infectious Diseases Pathology Branch and Rickettsial Zoonoses Branch, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Núcleo de Anatomica Patológia, Centro de Patologia do Instituto Adolfo Lutz, São Paulo, Brazil; Departamento de Vigilância em Saúde, Secretaria Municipal de Saúde de Campinas, São Paulo, Brazil
| | - Sandor E Karpathy
- Infectious Diseases Pathology Branch and Rickettsial Zoonoses Branch, National Center for Emerging and Zoonotic Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia; Núcleo de Anatomica Patológia, Centro de Patologia do Instituto Adolfo Lutz, São Paulo, Brazil; Departamento de Vigilância em Saúde, Secretaria Municipal de Saúde de Campinas, São Paulo, Brazil
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Abstract
Rocky Mountain spotted fever is typically undifferentiated from many other infections in the first few days of illness. Treatment should not be delayed pending confirmation of infection when Rocky Mountain spotted fever is suspected. Doxycycline is the drug of choice even for infants and children less than 8 years old.
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Abstract
Alcoholic individuals are at increased risk of infection in general, in part because of immune defects. In addition, associated situations, such as depressed mental status, increase risk to specific syndromes such as lung abscess related to depressed consciousness and aspiration. Social factors related to hygiene and living situations are also linked to specific microorganisms, such as Mycobacteria tuberculosis, Bartonella quintana, Vibrio vulnificus, and Capnocytophaga canimorus..
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10
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Walker DH. Rickettsial diseases in travelers. Travel Med Infect Dis 2012; 1:35-40. [PMID: 17291879 DOI: 10.1016/s1477-8939(03)00025-5] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2003] [Accepted: 03/11/2003] [Indexed: 10/27/2022]
Abstract
Often undiagnosed in travelers with acute nonspecific febrile illness, gastrointestinal, abdominal, pulmonary, neurologic, or cutaneous signs and symptoms, rickettsial diseases are transmitted in particular geographic and ecologic settings by ticks, fleas, chiggers, and lice. Recognition of an eschar at the vector inoculation site can be a key diagnostic clue for scrub typhus, African tick bite fever, and other tick-borne spotted fevers. Although laboratory confirmation is necessary, usually during convalescence, for an accurate diagnosis, a clinical diagnosis and empiric treatment with doxycycline are the standard practical approach. Knowledge of potential exposure, the natural history of the infection, and incubation periods of each rickettsiosis assist in considering particular rickettsioses.
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Affiliation(s)
- David H Walker
- Department of Pathology, Center for Biodefense and Emerging Infectious Diseases, University of Texas Medical Branch, 301 University Boulevard, Rm 1.116, Keiller Building, Galveston, TX 77555-0609, USA
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11
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Fang R, Ismail N, Walker DH. Contribution of NK cells to the innate phase of host protection against an intracellular bacterium targeting systemic endothelium. THE AMERICAN JOURNAL OF PATHOLOGY 2012; 181:185-95. [PMID: 22617213 DOI: 10.1016/j.ajpath.2012.03.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2011] [Revised: 02/10/2012] [Accepted: 03/22/2012] [Indexed: 11/19/2022]
Abstract
We investigated the mechanisms by which natural killer (NK) cells mediate innate host defense against infection with an endothelium-targeting intracellular bacterium, Rickettsia. We found that a robust Rickettsia-induced innate response in resistant mice cleared the bacteria early in the infection and was associated with significantly higher frequencies of splenic interferon (IFN)-γ (+) CD8(+) T cells and cytotoxic NK cells compared with susceptible mice. More importantly, NK cell-deficient Rag(-/-)γc(-/-) animals displayed significantly increased susceptibility to Rickettsia infection compared with NK cell-sufficient Rag(-/-) mice, as evidenced by impaired bacterial clearance, early development of severe thrombosis in the liver, and a decreased serum level of IFN-γ. Furthermore, the lack of NK cells also impaired host resistance of CB-17 scid mice to Rickettsia, similar to what was observed in Rag(-/-)γc(-/-) mice. Interestingly, perforin deficiency in Rag(-/-)Prf1(-/-) mice resulted in greater thrombosis and insignificantly different systemic levels of IFN-γ compared with Rag(-/-) mice, suggesting that perforin, which is mainly produced by NK cells, is involved in the prevention of vascular damage. Together, these findings reveal that NK cells mediate the innate phase of host protection against infection with rickettsiae, most likely via IFN-γ production. Furthermore, NK cells are involved in preventing rickettsial infection-induced endothelial cell damage, possibly via perforin production.
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Affiliation(s)
- Rong Fang
- Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609, USA
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12
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Kim CO, Huh AJ, Yeom JS, Lee KS, Chin BS, Han SH, Jeong SJ, Choi JY, Song YG, Kim JM. Lack of effect of dexamethasone on growth of Orientia tsutsugamushi Gilliam in mouse L929 cells. Yonsei Med J 2011; 52:624-9. [PMID: 21623605 PMCID: PMC3104446 DOI: 10.3349/ymj.2011.52.4.624] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
PURPOSE Previous studies and our own clinical experience suggest that concurrent corticosteroid treatment for severe rickettsial disease with multiorgan failure may improve the clinical course or reduce mortality. However, the use of corticosteroids as adjunctive treatment for rickettsial diseases is controversial. We attempted to determine the influences of corticosteroid on the growth of Orientia tsutsugamushi in vitro to justify and evaluate the clinical applicability of corticosteroid in rickettsial disease. MATERIALS AND METHODS L929 cells were infected with Orientia tsutsugamushi Gilliam. Dexamethasone was added to the cells at final concentrations of 10¹ and 10⁷ pg/mL. Cultures were incubated at 35°C and processed for flow cytometry on the 6th day after addition of dexamethasone. RESULTS Observation on the 6th day after treatment with dexamethasone in infected cultures revealed that there was no difference in fluorescence intensity among the treatment wells. Treatment of the cells with dexamethasone at concentrations of 10¹ and 10⁷ pg/mL showed no influence on the growth of Orientia tsutsugamushi. CONCLUSION Our results to show that isolated corticosteroid does not enhance the replication of Orientia tsutsugamushi in vitro. Concurrent use of anti-inflammatory or immunosuppressive doses of corticosteroids in conjunction with antibiotics may not have detrimental effects on the course of scrub typhus.
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Affiliation(s)
- Chang Oh Kim
- Department of Internal Medicine and AIDS Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Ae Jung Huh
- Department of Internal Medicine, National Health Insurance Corporation Ilsan Hospital, Goyang, Korea
| | - Joon Sup Yeom
- Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Kkot Sil Lee
- Department of Internal Medicine, Kwandong University Myongji Hospital, Kwandong University College of Medicine, Goyang, Korea
| | - Bum Sik Chin
- Department of Internal Medicine and AIDS Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Sang Hoon Han
- Department of Internal Medicine and AIDS Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Su Jin Jeong
- Department of Internal Medicine and AIDS Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Jun Yong Choi
- Department of Internal Medicine and AIDS Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - Young Goo Song
- Department of Internal Medicine and AIDS Research Institute, Yonsei University College of Medicine, Seoul, Korea
| | - June Myung Kim
- Department of Internal Medicine and AIDS Research Institute, Yonsei University College of Medicine, Seoul, Korea
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13
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Host, pathogen and treatment-related prognostic factors in rickettsioses. Eur J Clin Microbiol Infect Dis 2011; 30:1139-50. [PMID: 21519943 DOI: 10.1007/s10096-011-1208-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2011] [Accepted: 02/28/2011] [Indexed: 10/18/2022]
Abstract
Diseases caused by rickettsiae, which are vector-borne bacteria, vary widely from mild and self-limiting, to severe and life-threatening. Factors influencing this diversity of outcome are related to the host, to the infectious agent and to the treatment used to treat the infection. A literature search was conducted on PubMed using the phrases "factors-related severity, outcome, host, pathogen, Rickettsia conorii, R. rickettsii, R. africae, R. felis, R. prowazekii, R. typhi, genomics". Among host factors, old age and the male gender have been associated with poor outcome in rickettsioses. Co-morbidities, ethnical factors and the genetic background of the host also seem to influence the outcome of rickettsial diseases. Moreover, although the degree of the host response is beneficial, it could also partly explain the severity observed in some patients. Among pathogen-related factors, traditional concepts of factors of virulence had been challenged and genomic reductive evolution with loss of regulatory genes is the main hypothesis to explain virulence observed in some species, such as Rickettsia prowazekii, the agent of epidemic typhus. R. prowazekii is the more pathogenic rickettsiae and harbours the smaller genome size (1.1 Mb) compared to less or non-virulent species, and is not intracellularly motile, a factor considered as a virulence factor for other intracellular bacteria. The antibiotic regimen used to treat rickettsioses also has an influence on prognosis. Usual concepts of severity and virulence in rickettsioses are challenging and are frequently paradoxical. In this mini-review, we will describe factors currently thought to influence the outcome of the main rickettsioses responsible for illness in humans.
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Chen LF, Sexton DJ. What's New in Rocky Mountain Spotted Fever? Infect Dis Clin North Am 2008; 22:415-32, vii-viii. [DOI: 10.1016/j.idc.2008.03.008] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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15
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Castelli F, Capone S, Pedruzzi B, Matteelli A. Antimicrobial prevention and therapy for travelers' infection. Expert Rev Anti Infect Ther 2008; 5:1031-48. [PMID: 18039086 DOI: 10.1586/14787210.5.6.1031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
International journeys are increasing and more than 70 million people from industrialized countries cross the borders of tropical countries every year. More than 50% of them will suffer from some form of infectious illness, ranging from mild travelers' diarrhea to severe dengue fever to fatal malaria, with a wide spectrum of microbiological entities. Travel-related respiratory infections, including TB, and sexually transmitted infections are also increasingly reported. Awareness of travel-related risk is not always adequate among international travelers. Specific training on travel medicine-related issues, as well as better diagnostic facilities for imported diseases, is crucial for physicians and nurses in industrialized countries.
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Affiliation(s)
- Francesco Castelli
- University of Brescia, Unit for Tropical and Imported Diseases, Spedali Civili General Hospital, Piazza Spedali Civili, 1 25123 Brescia, Italy.
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16
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Sahni SK, Rydkina E, Sahni A, Joshi SG, Silverman DJ. Potential Roles for Regulatory Oxygenases in Rickettsial Pathogenesis. Ann N Y Acad Sci 2005; 1063:207-14. [PMID: 16481516 DOI: 10.1196/annals.1355.033] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Clinical and experimental evidence suggests an important role for oxidative stress and associated cellular defense mechanisms in the pathogenesis of vasculopathic rickettsioses. Our laboratory has reported that R. rickettsii infection of endothelial cells in vitro induces the expression of HO-1, the inducible isoform of the antioxidant defense enzyme heme oxygenase. HO-1 plays a critical role in maintaining the integrity of the vasculature and controls the functioning of the cyclooxygenase (COX) system. This study was undertaken to investigate the expression of COX and HO isozymes during in vitro infection of EC with two major representatives of spotted fever group Rickettsia species. The mRNA expression of COX-2 was significantly increased in endothelial cells infected with R. rickettsii and R. conorii, while that of COX-1 remained unaffected. Western blot analysis using total protein lysates from infected endothelial cells and corresponding uninfected controls further confirmed specific induction of COX-2 in response to infection. ELISA measurements on culture supernatants also suggested enhanced secretion of 6-keto PGF(1alpha) (stable hydrolysis product of PGI(2) and PGE(2). As a functional consequence of HO-1 upregulation, increased expression of the iron storage protein ferritin following R. rickettsii and R. conorii infection was also evident. Since products of HO-1 and COX-2 reactions govern a variety of physiologically important functions in the vasculature, further studies to define their regulation in the host cell should provide useful insights into the pathogenesis of rickettsial diseases.
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Affiliation(s)
- Sanjeev K Sahni
- Hematology-Oncology Unit, Department of Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA.
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Ndip LM, Bouyer DH, Travassos Da Rosa APA, Titanji VPK, Tesh RB, Walker DH. Acute spotted fever rickettsiosis among febrile patients, Cameroon. Emerg Infect Dis 2004. [PMID: 15109409 DOI: 10.32012/eid1003.020713] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023] Open
Abstract
Although potential arthropod vectors are abundant in Cameroon, acute febrile illnesses are rarely evaluated for arboviral or rickettsial infections. Serum samples from 234 acutely febrile patients at clinics in Tiko and Buea, Cameroon, were examined for antibodies to Rickettsia africae and African alphaviruses and flaviviruses. These serum samples did not contain antibodies against typhoid, and blood malarial parasites were not detected. Serum samples of 32% contained immunoglobulin M antibodies reactive with R. africae by immunofluorescence assay and were reactive with outer membrane proteins A and B of R. africae by immunoblotting. These findings established a diagnosis of acute rickettsiosis, most likely African tick-bite fever. Hemagglutination inhibition testing of the serum samples also detected antibodies to Chikungunya virus (47%) and flaviviruses (47%). High prevalence of antibodies to arboviruses may represent a major, previously unrecognized public health problem in an area where endemic malaria and typhoid fever have been the principal diagnostic considerations.
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Affiliation(s)
- Lucy M Ndip
- University of Buea, Buea, South West Province, Cameroon
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Ndip LM, Bouyer DH, Da Rosa APT, Titanji V, Tesh RB, Walker DH. Acute spotted fever rickettsiosis among febrile patients, Cameroon. Emerg Infect Dis 2004; 10:432-7. [PMID: 15109409 PMCID: PMC3322773 DOI: 10.3201/eid1003.020713] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Although potential arthropod vectors are abundant in Cameroon, acute febrile illnesses are rarely evaluated for arboviral or rickettsial infections. Serum samples from 234 acutely febrile patients at clinics in Tiko and Buea, Cameroon, were examined for antibodies to Rickettsia africae and African alphaviruses and flaviviruses. These serum samples did not contain antibodies against typhoid, and blood malarial parasites were not detected. Serum samples of 32% contained immunoglobulin M antibodies reactive with R. africae by immunofluorescence assay and were reactive with outer membrane proteins A and B of R. africae by immunoblotting. These findings established a diagnosis of acute rickettsiosis, most likely African tick-bite fever. Hemagglutination inhibition testing of the serum samples also detected antibodies to Chikungunya virus (47%) and flaviviruses (47%). High prevalence of antibodies to arboviruses may represent a major, previously unrecognized public health problem in an area where endemic malaria and typhoid fever have been the principal diagnostic considerations.
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Affiliation(s)
- Lucy M. Ndip
- University of Buea, Buea, South West Province, Cameroon
| | | | | | | | - Robert B. Tesh
- University of Texas Medical Branch, Galveston, Texas, USA
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Li Z, Díaz-Montero CM, Valbuena G, Yu XJ, Olano JP, Feng HM, Walker DH. Identification of CD8 T-lymphocyte epitopes in OmpB of Rickettsia conorii. Infect Immun 2003; 71:3920-6. [PMID: 12819078 PMCID: PMC161984 DOI: 10.1128/iai.71.7.3920-3926.2003] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The 1.2-kb DNA fragment of the Rickettsia conorii outer membrane protein B gene (OmpB(451-846)) was subcloned using site-specific PCR primers and expressed as six smaller fragments: OmpB(458-652), OmpB(595-744), OmpB(595-654), OmpB(645-692), OmpB(689-744), and OmpB(739-848). NCTC cells transfected with a mammalian expression vector expressing the fragments OmpB(689-744) and OmpB(739-848) stimulated immune anti-R. conorii CD8 T lymphocytes, suggesting the presence of CD8 T-lymphocyte-stimulating epitopes on these fragments. In order to further characterize the CD8 T-lymphocyte-stimulatory elements, CD8 T-lymphocyte epitopes on OmpB(689-744) and OmpB(739-848) were mapped by overlapping synthetic peptides. The ability of these synthetic peptides to stimulate immune CD8 T lymphocytes was determined by gamma interferon (IFN-gamma) production and cell proliferation after incubation with simian virus 40-transformed murine vascular endothelial cells in the presence of a 20 micro M solution of each synthetic peptide. Five synthetic peptides, SKGVNVDTV (OmpB(708-716)), ANVGSFVFN (OmpB(735-743)), IVSGTVGGQ (OmpB(749-757)), ANSTLQIGG (OmpB(789-797)), and IVEFVNTGP (OmpB(812-820)), induced secretion of IFN-gamma at significantly higher levels than the controls. Three of these five peptides, SKGVNVDTV (OmpB(708-716)), ANSTLQIGG (OmpB(789-797)), and IVEFVNTGP (OmpB(812-820)), also stimulated the proliferation of immune CD8 T lymphocytes. Significantly higher levels of specific cytotoxic T-lymphocyte killing were observed with the same three synthetic peptides, SKGVNVDTV (OmpB(708-716)), ANSTLQIGG (OmpB(789-797)), and IVEFVNTGP (OmpB(812-820)).
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Affiliation(s)
- Zhen Li
- Department of Pathology, WHO Collaborating Center for Tropical Diseases, University of Texas Medical Branch at Galveston, Galveston, Texas 77555-0609, USA
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20
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La Scola B, Raoult D. Laboratory diagnosis of rickettsioses: current approaches to diagnosis of old and new rickettsial diseases. J Clin Microbiol 1997; 35:2715-27. [PMID: 9350721 PMCID: PMC230049 DOI: 10.1128/jcm.35.11.2715-2727.1997] [Citation(s) in RCA: 310] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Affiliation(s)
- B La Scola
- Unité des Rickettsies, UPRESA 6020, Faculté de Médecine, Université de la Méditerrannée, Marseille, France
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21
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Breitschwerdt EB, Davidson MG, Hegarty BC, Papich MG, Grindem CB. Prednisolone at anti-inflammatory or immunosuppressive dosages in conjunction with doxycycline does not potentiate the severity of Rickettsia rickettsii infection in dogs. Antimicrob Agents Chemother 1997; 41:141-7. [PMID: 8980770 PMCID: PMC163675 DOI: 10.1128/aac.41.1.141] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Dogs were experimentally inoculated with Rickettsia rickettsii to determine if anti-inflammatory or immunosuppressive dosages of prednisolone, when administered in conjunction with an antirickettsial antibiotic (doxycycline), induced therapeutically relevant pathophysiological consequences that ultimately influence disease outcome. Although the duration of rickettsemia was prolonged in dogs receiving immunosuppressive, but not anti-inflammatory, corticosteroids, concurrent administration of doxycycline and corticosteroids conferred no other detected detrimental effects. Treatment with doxycycline or doxycycline in conjunction with prednisolone resulted in decreased R. rickettsii-specific antibody titers; however, examination of appropriately timed acute- and convalescent-phase serum samples would have facilitated an accurate diagnosis of Rocky Mountain spotted fever (RMSF) in all 16 dogs. We conclude that the concurrent use of anti-inflammatory or immunosuppressive doses of prednisolone in conjunction with doxycycline, early in the course of experimental RMSF, confers no clinically relevant detrimental effects and that additional studies might be indicated to detect possible beneficial effects in cases of severe or potentially fulminant RMSF. However, because the illness induced in these dogs was of mild to moderate severity, the results of this study should definitely not be construed as supporting the safety or efficacy of prednisolone for treatment of severe canine or human RMSF.
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Affiliation(s)
- E B Breitschwerdt
- Department of Companion Animal and Special Species Medicine, College of Veterinary Medicine, North Carolina State University, Raleigh 27606, USA.
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22
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La Scola B, Raoult D. Diagnosis of Mediterranean spotted fever by cultivation of Rickettsia conorii from blood and skin samples using the centrifugation-shell vial technique and by detection of R. conorii in circulating endothelial cells: a 6-year follow-up. J Clin Microbiol 1996; 34:2722-7. [PMID: 8897172 PMCID: PMC229393 DOI: 10.1128/jcm.34.11.2722-2727.1996] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Rickettsia conorii, an obligate intracellular bacterium that infects vascular endothelial cells, is the etiologic agent of Mediterranean spotted fever. We correlated the results of 205 R. conorii blood and skin cultures for 157 patients and the results of 48 detections of R. conorii in circulating endothelial cells (CEC) for 41 patients with relevant serological, clinical, and therapeutic data. R. conorii was cultured from 40% of patients and 29.8% of samples. R. conorii was detected in CEC in 50% of samples, representing 46.2% of patients. When these calculations were limited to the samples from untreated patients prior to their seroconversion to R. conorii, the sensitivity of culture was 59%, whereas it remained at 50% for detection in CEC. We also performed PCRs for the detection of R. conorii on eight shell vial supernatants from positive cultures and on 43 blood samples. Only nonfrozen supernatants from fresh cultures were positive. The methods described in this report are suitable for use in all laboratories. Our findings suggest that for samples to be suitable for culture they must be collected prior to the initiation of an antibiotic regimen, as early as possible in the course of the disease, and be inoculated onto shell vials with minimal delay, if R. conorii is to be successfully isolated. For patients who have been treated or who have a delayed diagnosis, detection of R. conorii in CEC remains helpful.
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Affiliation(s)
- B La Scola
- Unité des Rickettsies, Centre National de la Recherche Scientifique: EP J 0054, Faculté de médecine, Marseille, France
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Affiliation(s)
- L I Kaplan
- Division of Internal Medicine, Cooper Hospital/University Medical Center, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School at Camden 08103, USA
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Affiliation(s)
- J L Silber
- Department of Medicine, Cooper Hospital/University Medical Center, University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School at Camden, USA
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Herrero-Herrero JI, Ruiz-Beltrán R, Walker DH. Antigens of Rickettsia conorii recognized by seropositive healthy people from Salamanca (central-west Spain). Eur J Epidemiol 1993; 9:59-63. [PMID: 8472802 DOI: 10.1007/bf00463091] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
The antigenic reactivity in Western immunoblotting assay of individual Rickettsia conorii components with sera of healthy people living in Salamanca Province, an endemic zone of Mediterranean spotted fever, is evaluated. Polypeptides of molecular weights 100 kDa (92.7%), 135 kDa (75.6%), 160 kDa (70.7%) and 115 kDa (48.8%) were recognized by a higher proportion of sera with indirect immunofluorescent antibody test titers > or = 1:80. Reaction with apparent rickettsial lipopolysaccharide was found in 15 (36.6%) of these samples. The involvement of different rickettsial strains, atypical routes of inoculation, varying content of the inoculum, and host factors may be determinants of the clinical expression of the spotted fever group rickettsial infection in people who produce antibodies reactive with Rickettsia conorii antigens.
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Affiliation(s)
- A S Boyd
- Department of Dermatology, Texas Tech University Health Sciences Center School of Medicine, Lubbock
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28
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Schattner A, Leitner M, Keysary A, Geltner D. Case report: fatal seronegative rickettsial infection diagnosed by the polymerase chain reaction. Am J Med Sci 1992; 303:392-4. [PMID: 1605168 DOI: 10.1097/00000441-199206000-00007] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A previously healthy man presented with a five day history of high fever and headache, later followed by rash and the appearance of jaundice. On the second hospital day, he suddenly developed seizures, lapsed into a coma, and died. Polymerase chain reaction (PCR) amplification revealed a 434 base pairs DNA fragment common to the genome of typhus and spotted fever group rickettsiae in the patient's blood (estimated at about 1 x 10(2) organisms/ml), and to a lesser degree in the cerebrospinal fluid. However, serological tests for rickettsiae remained negative. PCR techniques may confirm the diagnosis at an early stage, even though the rickettsemia may be minimal and the patient seronegative.
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Affiliation(s)
- A Schattner
- Department of Medicine A, Kaplan Hospital, Rehovot, Israel
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Tselentis Y, Babalis TL, Chrysanthis D, Gikas A, Chaliotis G, Raoult D. Clinicoepidemiological study of murine typhus on the Greek island of Evia. Eur J Epidemiol 1992; 8:268-72. [PMID: 1644147 DOI: 10.1007/bf00144812] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Cases of murine typhus were described in Chalkis, capital town of the island Evia in Greece. In the present work a prospective study on murine typhus was carried out in Chalkis General Hospital in 1985, is presented. During this year 49 cases, serologically confirmed using indirect fluorescence assay, were diagnosed. Signs and symptoms of the patients as well as preliminary epidemiological data are reported in this paper.
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Affiliation(s)
- Y Tselentis
- Department of Clinical Parasitology, Zoonosis and Geographical Medicine, University of Crete Staurakia, Heraklion, Greece
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Abstract
Rickettsial diseases have a diversity of epidemiologic characteristics reflective of the variety of ecologic situations in which the obligate intracellular bacteria are transmitted to humans. For the spotted fever group (SFG) rickettsiae, Rickettsia typhi, R. tsutsugamushi, Coxiella burnetii, and the human ehrlichial agent, humans are a dead-end host who plays no role in the maintenance of the organism in nature. All rickettsioses exist as zoonoses. Moreover, all rickettsiae are found in infected arthopods, which generally serve as the natural hosts and can transmit the infection to the next generation of ticks, mites, chiggers, or fleas. From our anthropocentric viewpoint, Q fever aerosol infection from parturient animals and Brill-Zinsser disease ignited epidemics of louse-borne epidemic typhus are exceptions. However, silent cycles of C. burnetii in ticks and R. prowazekii in the flying squirrel flea may have maintained these agents in transovarial or enzootic cycles for eons before humans and their domestic animals arrived on the scene. Thus, the epidemiology of rickettsial diseases must be recognized as an unfortunate aberration of the rickettsial economy. Several excellent reviews of rickettsial ecology contain a wealth of useful information.
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Affiliation(s)
- D H Walker
- Department of Pathology, University of Texas Medical Branch, Galveston 77550
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