12 Most of the cases of murine typhus are mild and signs in untreated patients last for 7 to 14 days (Table 1). Patients usually present an abrupt onset of
symptoms like fever, rash, cough, headaches, maculopapular exanthema on the trunk to the half-patients, chills, as well as with myalgias and hepatomegaly.11 Less common manifestations of murine typhus are lymphadenopathy (4%) and splenomegaly (5%).12 In rare cases, aseptic meningitis, deafness, deep venous thrombosis, and even death have been reported with a fatality rate which may be as high as 4%.13 Diagnosis may be missed because the rash is not always presented. The rash is nonspecific and its prevalence differs as 20% of patients from Thailand presented rash, 38% of patients from Laos, 49% of patients from Texas, 80% of patients from Greece, and 62.5% of patients from Spain.12,14–17 None of our patient presented rash. A major role for the early diagnosis of murine typhus is the Histone Methyltransferase inhibitor epidemiologic investigation of patients. Murine typhus should be considered to patients from places with a high rat population like tropical countries, and also northern countries late in summer or early in autumn. When choosing a diagnostic method, one must take into account its specificity, Atezolizumab mw sensitivity, cost, the amount of antigen required, and its commercial availability. The microorganisms can be isolated by inoculation of specimens onto conventional cell cultures (Vero
cells).18 The most recent technique is the centrifugation shell vial method, in which specimens are inoculated in Vero or L299 cells on a coverslip within the shell vial and the ensuing centrifugation enhances the attachment and penetration Carbohydrate of rickettsiae into cells.18 The technique allows the identification of new rickettsiae and ensures early diagnosis because it can give a positive result before the antibody titer rises.19 The delay between sampling and inoculation in shell vials as well as the use of antibiotic therapy prior to sampling are important factors that limit the possibility of a positive culture.18 However, culture and isolation of Rickettsia
sp. must only be carried out in Biosafety Level 3 laboratories. PCR is a rapid, sensitive, and specific method and is considered the technique of choice for early diagnosis of the disease because it can give positive result before seroconversion.18,20 It is a significant tool in detecting rickettsiae in blood, skin biopsies, and arthropods and it is also used for differentiating the various species of Rickettsia.18 The genes that are specific of the typhus group Rickettsia are the rrs, gltA, ompB, and the gene D.18 Serological tests are the most frequently used and widely available methods for the diagnosis of murine typhus. Indirect immunofluorescence assay (IFA) adapted to a micromethod format is the reference method for the serodiagnosis of Rickettsia in most laboratories.