Disease relevance of Scrub Typhus

• METHODS: Serial HIV-1 viral load determinations were made in ten Thai adults with scrub typhus, who were not receiving antiretroviral therapy, and in five HIV-1-infected patients who had other infections (four malaria, one leptospirosis), during and after acute infections [1].
• The results of this study suggest that O. tsutsugamushi does invade the CSF and that scrub typhus should be considered one of the causes of mononuclear meningitis in areas of endemicity [2].
• Thai patients with scrub typhus caused by the intracellular pathogen Orientia tsutsugamushi displayed elevated plasma concentrations of granzymes A and B, interferon-gamma (IFN)-gamma-inducible protein 10, and monokine induced by IFN-gamma [3].
• Eleven other sera (1.2%) were positive for scrub typhus and spotted fever group rickettsiae and four (0.4%) were positive for scrub typhus, spotted fever group, and typhus group rickettsiae [4].
• A patient was admitted to our hospital with fever of unknown origin, lymphadenopathy and moderate anemia.The diagnosis of scrub typhus (tsutsugamushi disease) was established on specific serologic demonstration of antibodies to the cross-reacting proteins OX-K antigen and reaffirmed by successful treatment with doxycycline [5].

High impact information on Scrub Typhus

• INTERPRETATION: Rifampicin is more effective than doxycycline against scrub-typhus infections acquired in northern Thailand, where strains with reduced susceptibility to antibiotics can occur [6].
• Sera from HIV-1-infected patients with scrub typhus and from mice immunised with O. tsutsugamushi were examined for HIV-1-suppressive activity [1].
• Chloramphenicol, gentamicin, and ciprofloxacin against murine scrub typhus [7].
• Host defenses in experimental scrub typhus: inflammatory response of congenic C3H mice differing at the Ric gene [8].
• Host defenses in experimental scrub typhus: effect of chloramphenicol [9].

Chemical compound and disease context of Scrub Typhus

• Short-course doxycycline treatment versus conventional tetracycline therapy for scrub typhus: a multicenter randomized trial [10].
• Azithromycin therapy for scrub typhus during pregnancy [11].
• We evaluated the effect of roxithromycin, a macrolide antibiotic, on scrub typhus in children [12].
• Under the impression of scrub typhus, minocycline was administered [13].
• The recombinant Sta22 protein eluted from polyacrylamide gels induced a strong proliferative response from the scrub typhus rickettsiae reactive T-cell line [14].

Biological context of Scrub Typhus

• In all cases, no scrub typhus rickettsiae were found in the litters examined on days 1, 7, and 30 postpartum, and no antibody was found in sera collected 1 and 2 months postpartum [15].
• Three women had stillbirths, 1 an abortion and 1 a low birthweight baby, which suggests that ciprofloxacin should not be used for treating pregnant women and that scrub typhus leads to severe adverse effects during pregnancy [16].

Anatomical context of Scrub Typhus

• To understand the pathogenesis of scrub typhus, we have investigated the induction of tumor necrosis alpha (TNF-alpha) and interleukin-6 (IL-6) by O. tsutsugamushi in two murine macrophage cell lines [17].
• We detected immunoreactive interferon-gamma (IFN-gamma) both in cerebrospinal fluid (CSF) and in serum of 5 patients with scrub typhus, one with meningitis and 4 other cases with neither CSF pleocytosis nor blood-CSF barrier dysfunction [18].
• The influence of tsutsugamushi fever infection on the metabolism of blood lymphocytes of mice differing in susceptibility to Rickettsia tsutsugamushi and of rifampicine and tetracycline treatment was studied [19].

Gene context of Scrub Typhus

• To understand the pathogenesis of scrub typhus, we examined chemokine and cytokine production after infection with O. tsutsugamushi in mice [20].
• The dipstick assays were the Integrated Diagnostics (Baltimore, MD) Dip-S-Ticks Scrub Recombinant (r56) dipstick test (INDX assay) and the PanBio (Brisbane, Australia) Scrub Typhus IgM and IgG Rapid Immunochromatographic test (PanBio assay) [21].
• IFN-gamma, interleukin (IL)-18, and IL-15 levels were elevated only in patients with scrub typhus, whereas IL-12p40 and tumor necrosis factor-alpha concentrations were elevated in both patient groups, although more so in scrub typhus [22].
• Theses primers led to a 78-bp fragment by amplifying the genomic DNAs from five serovariants, i.e., the Gilliam, Karp, Kato, Kawasaki, and Kuroki strains of R. tsutsugamushi, and also the DNA from blood clots of patients with scrub typhus, even at the early stage of onset of the disease [23].
• A polymerase chain reaction system for rapid diagnosis of scrub typhus within six hours [24].

Analytical, diagnostic and therapeutic context of Scrub Typhus

• The use of doxycycline, as a prophylactic antibiotic against scrub typhus was investigated in a prospective, randomized, double-blind study [25].
• Both the immunoglobulin M (IgM) and IgG antibody titers of 12 sequential sera from four patients with scrub typhus were obtained by IFA and ELISA [26].
• When subjects who failed to comply with scheduled administration of doxycycline were removed from the analysis, the incidence rate of scrub typhus in the control group was five times greater than that in the drug group (P = 0.04) [27].
• The reactivity of sera from patients of Tsutsugamushi disease (scrub typhus) with the antigenic polypeptides of Rickettsia tsutsugamushi was analyzed by the immunoblotting method [28].
• Diagnosis of scrub typhus in Malaysian aborigines using nested polymerase chain reaction [29].

References