Invasive Haemophilus influenzae type a infection and polyarthritis in a 72-year-old Japanese man: A case report.

Haemophilus influenzae is a small, nonmotile, non-spore-forming bacterium classified into 6 serotypes (a to f) and non-typeable strains that lack a capsule. Although H. influenzae serotype a (Hia) is prevalent in Canada, the United States, Brazil, Australia, across the African continent, and several other locations, it has not been reported in Japan thus far. Our case was of a 72-year-old Japanese man who sought medical consultation after presenting with chills, fever, and polyarthritis. Cultures of blood and synovial fluid from the left knee revealed H. influenzae infection. Diagnostic imaging showed poor contrast regions in both kidneys, fluid retention around both knee joints, the left shoulder joint, and both elbow joints. Subsequently, the patient was diagnosed with invasive H. influenzae infection accompanied by polyarthritis and renal infarction. 16S ribosomal RNA gene sequencing revealed that the bacterial strain was Hia. The patient was treated with antimicrobial agents and arthroscopic curettage. We present a case of invasive Hia infection accompanied by polyarthritis and renal infarction. To the best of our knowledge, this is the first case of Hia infection in Japan. The case is very rare considering that the disease occurred in an elderly patient who developed polyarthritis.

Chlamydia trachomatis serotype A infections in the Amazon region of Brazil: prevalence, entry and dissemination

INTRODUCTION: Chlamydia infection is associated with debilitating human diseases including trachoma, pneumonia, coronary heart disease and urogenital diseases. Serotypes of C. trachomatis show a fair correlation with the group of diseases they cause, and their distribution follows a well-described geographic pattern. Serotype A, a trachoma-associated strain, is known for its limited dissemination in the Middle East and Northern Africa. However, knowledge on the spread of bacteria from the genus Chlamydia as well as the distribution of serotypes in Brazil is quite limited. METHODS: Blood samples of 1,710 individuals from ten human population groups in the Amazon region of Brazil were examined for antibodies to Chlamydia using indirect immunofluorescence and microimmunofluorescence assays. RESULTS: The prevalence of antibodies to Chlamydia ranged from 23.9% (Wayana-Apalai) to 90.7% (Awa-Guaja) with a mean prevalence of 50.2%. Seroreactivity was detected to C. pneumoniae and to all serotypes of C. trachomatis tested; furthermore, we report clear evidence of the as-yet-undescribed occurrence of serotype A of C. trachomatis. CONCLUSIONS: Specific seroreactivity not only accounts for the large extent of dissemination of C. trachomatis in the Amazon region of Brazil but also shows an expanded area of occurrence of serotype A outside the epidemiological settings previously described. Furthermore, these data suggest possible routes of Chlamydia introduction into the Amazon region from the massive human migration that occurred during the 1,700s. .