Buruli ulcer is a skin disease caused by Mycobacterium ulcerans (M. ulcerans). In this review, we introduce our recent studies and other important works. Lesions of Buruli ulcer are usually painless, despite the extensive tissue necrosis. We have reported that mice inoculated with M. ulcerans show nerve degeneration and absence of pain, but the mechanism evoking the nerve damage have not been clarified. In order to define whether mycolactone, a toxic lipid produced by M. ulcerans, can induce nerve damages, we have injected mycolactone A/B to BALB/c mouse footpads. Mycolactone induced footpad swelling, and sensory test showed hyperesthesia on day 7 and 14, recovery on day 21, and hypoesthesia on days 28 and 42. Histologically, nerve bundles showed hemorrhage, neutrophilic infiltration, and loss of Schwann cell nuclei on days 7 and 14. Semithin section studies revealed vacuolar change of Schwann cells started on day 14, which subsided by day 42, but myelinated fiber density remained low. This study suggests that mycolactone directly damages nerves and is responsible for the absence of pain characteristic of Buruli ulcer. In the human lesions, presence of neuritis is reported (Rondini S, 2006), and murine studies showed "autoamputation" (Addo P, 2005). In order to prevent the serious deformities evoked by Buruli ulcer, further studies are necessary.

View full abstract

  We aimed to elucidate the patterns and trends of autochthonous leprosy in Japan from 1964 to 2009, to compare them with the findings from other studies of leprosy in decline. Data on registered leprosy cases in Japan in the period 1964-2009 were analysed with reference to trends in case detection, geographical distribution, age at diagnosis, sex, classification and family history. A consistent decline in leprosy case detection was observed in all areas of the country over the period 1964-2009. Highest incidence was consistently in Okinawa. Autochthonous leprosy has not been reported in anyone born in Japan since 1980. Increasing average age and a shift towards lower latitudes were demonstrated throughout the period. Analyses of data on autochthonous cases revealed patterns similar to those reported in other countries with declining leprosy.
  Okinawa has had the highest incidence of leprosy in all of Japan since the first national survey in 1900. Several possible explanations include the difference of leprosy control history between Okinawa and the rest of Japan, Okinawa's unique geographical condition, large-scale problem of stigma and discrimination against leprosy patients and delayed improvement of socio-economic conditions.

View full abstract

  Drugs included in new-quinolone are used for the treatment of leprosy with single lesion. These drugs are also known to be effective drugs for the treatment of multi-drug resistant M. tuberculosis. Recent emergence of new-quinolone resistant M. leprae and M. tuberculosis enforced the urgent elucidation of the mode of emergence of new-quinolone resistant strains. In this review, new-quinolone drugs, their mode of action and mechanism of acquisition of resistance by M. leprae and M. tuberculosis were explained. And rapid differentiation methods for resistant bacilli were also introduced.

View full abstract

  Leprosy is suspected to develop after a long period of latency following infection with Mycobacterium leprae (M. leprae) during infancy, but definitive proof has been lacking. We found a rare case of leprosy in a chimpanzee (Pan troglodytes) born in West Africa (Sierra Leone) and brought to Japan around 2 years of age. At 31, the ape started exhibiting pathognomic signs of leprosy. Pathological diagnosis, skin smear, serum anti-phenolic glycolipid-I (PGL-I) antibody, and by PCR analysis demonstrated lepromatous leprosy. Single-nucleotide polymorphism (SNP) analysis verified the West African origin of the bacilli. This occurrence suggests the possibility of leprosy being endemic among wild chimpanzees in West Africa, potentially posing a zoonotic risk.

View full abstract

  The epidemiological situation of leprosy is reported by the health division of each country to WHO. The reported data is collected by WHO and is immediately run on the Weekly Epidemiological Record. On this latest edition, data from the beginning of 2010 was reported. In almost all of the highly endemic countries, control activities have been integrated within the general healthcare system. However, early case detection and prompt treatment with MDT remain the cornerstone of leprosy. In order to reduce the physical, mental and socioeconomic burden of leprosy, much remains to be done.

View full abstract

[in Japanese]

View full abstract

  A letter of Matuki Miyazaki, the director of Kyushu Sanatorium to Masao Ota was found in the materials of Masao Ota stored at the library of University of Tokyo.
  Miyazaki, who was president of 12th annual meeting of Japanese Leprosy Association in Kumamoto in 1938, thanked Ota for the acceptance of a special lecture.
  Ota lectured on the title of inoculation of leprosy bacteria to animals.

View full abstract

  The Leprosy Mailing List (LML) is an e-mailing list open to whoever interested in the field from all over the world. It acts as a forum for exchanging information related to Hansen's disease. It was established in February 2001 in Italy, and the present moderator of the LML is Dr. Salvatore Noto. He and his colleague have recently introduced an atlas for diagnosing Hansen's disease which they brought together information and photos collected through the LML. The atlas is divided into three sections, (1) Introduction, (2) Cardinal signs, and (3) Diagnosis and the clinical spectrum of leprosy, and they are all accompanied with relevant photos.
  This time, Dr. Noto kindly permitted us to translate the atlas into Japanese to be published in the Japanese Journal of Leprosy and posted in the Japanese Leprosy Association homepage. This article includes the translation and some of the most informative photos. For more information, please refer to the homepage where you will find all photos in the atlas.

View full abstract

[in Japanese]

View full abstract