613. From deadly fatal to easily overlooked among Karp strain: diversity of clinical features of Scrub typhus in Fukushima, Japan
Session: Poster Abstract Session: Oh One World: Infections from Near and Far
Thursday, October 27, 2016
Room: Poster Hall
  • 613 IDWeek Narita 10-19-16.pdf (393.3 kB)
  • Background: Scrub typhus (ST) is endemic in Fukushima, where the highest number has been reported from 2006 to 2011 in Japan. In 2009, One fatal case of ST had reported with delay of diagnosis and treatment. This study aimed to determine clinical features among strains (Karp, Irle/Kawasaki, Hirano/Kuroki) in this endemic area.

    Methods: We reviewed the charts of patients diagnosed with ST from 2008 to 2015 at Ohta Nishinouchi General Hospital, the largest teaching hospital in Koriyama-city, located in the center of Fukushima prefecture.

    Results: Total 48 cases (serotype Karp 21, serotype Irie/Kawasaki 19, Hirano/Kuroki 8) of ST were confirmed by elevated specific IgM and IgG in the paired sera and positivity by real-time PCR analysis of eschars. The clinical features categorized from type 1 to 4 based on two axes of characteristics: severity and presentation: triad (fever, rash and eschar) or atypical presentation without triad. Type 1 (mild/typical: 54% of 26/48) showed clinical triad with stable clinical course on treatment, Type 2 (severe/typical: 5% of 3/48) presented with shock found to have shock state with DIC. Type 3 (severe/ atypical: 15% of 7/48) predominantly showed organ damage such as arrhythmia and meningoencephalitis. Type 4 (mild/atypical: 25% of 12/48) presented with the lack of triad, easily overlooked and resolved without treatment on occasion (4% of 2/48). In terms of Phylogenetic information by the gene sequences of the locus for the 56-kDa proteins, all type 2 (severe/typical) located closely to Karp, JP-1 and Karp variant. Serum type of Karp distributed widely from Type 1 to 4 (57, 14, 19 and 10%, respectively), compared with Irie/Kawasaki of Type 1, 3 and 4 (58,16,26%, respectively) and Hirano/Kuroki of Type 1 and 4 (37.5 and 62.5%, respectively).

    Conclusion: The clinical features of each strains (Karp, Irie/Kawasaki and Hirano/Kuroki) of ST in Fukushima, Japan found to have a diversity in severity, typical and atypical presentation. Serotype of Karp has wide clinical features from fatal to mild cases compared with Irie/Kawasaki and Hirano/Kuroki. The virulence of Karp (especially JP-1) in Type 2 should be noted. Atypical presentation of ST should not be missed as differential diagnosis of fever in this endemic area.

    Masashi Narita, M.D., Department of Medicine, Okinawa Chubu Hospital, Uruma, Okinawa, Japan, Naota Monma, Ph.D, Department of Microbiology, Fukushima Prefectural Institute of Public Health, Fukushima-city, Fukushima, Japan, Kazuki Chiba, Ph.D, Fukushima Prefectural Institute of Public Health, Fukushima-city, Fukushima, Japan, Rie Suzuki, Ph.D, Fukushima prefectural institutes of health, Fukushima-city, Fukushima, Japan and Hiromi Fujita, Ph.D, Mahara acari institute, Anan city, Tokushima, Japan


    M. Narita, None

    N. Monma, None

    K. Chiba, None

    R. Suzuki, None

    H. Fujita, None

    Findings in the abstracts are embargoed until 12:01 a.m. CDT, Wednesday Oct. 26th with the exception of research findings presented at the IDWeek press conferences.