[Japanese spotted fever complicated by acute respiratory failure].

A 66-year-old male was admitted to our hospital, presenting a high fever and generalized erythema on June 9, 1999. Physical examination revealed many eschars on his legs. Laboratory examinations were as follows: platelet counts, 5.5 x 10(4)/microliter: FDP, 25 micrograms/ml: TAT, 70.9 ng/ml: GOT, 177 IU/l, GPT, 174 IU/l: CRP, 32.3 mg/dl. Based on these findings, he was diagnosed as having rickettsiosis with DIC, and minocycline (200 mg/day) and heparin were started immediately, but had no clinical effect for 3 days. Blood gas analysis showed severe hypoxia and the chest CT scan revealed increased CT value in all lung fields with reticular shadows in the lower fields and pleural effusion, suggested interstitial pneumonia. Methyl-prednisolone pulse therapy was started on June 12, after which he completely recovered. Anti-Rikettia japonica IgM antibody was found to be x8,192 by immunofluorescent test, establishing the diagnosis of Japanese spotted fever. Acute respiratory failure with interstitial pneumonia shadows should be emphasized as a complication of severe rickettsiosis.