Hansen's disease (leprosy) in Japan, 1947-2020: an epidemiologic study during the declining phase to elimination.

OBJECTIVES: Leprosy, or Hansen's disease was a major public health problem in Japan in the early 20th century. Today, the number of new cases has decreased significantly. We aimed to investigate the trends of leprosy in Japan over the past 73 years and the challenges faced in recent years. METHODS: We assessed the data on newly registered cases of leprosy from 1947 to 2020. RESULTS: A total of 10,796 newly registered cases of leprosy were reported during the study period, of which 7573 were registered in mainland Japan, 2962 in Okinawa, and 250 were of foreign origin. Most autochthonous cases were born before 1950 in mainland Japan and before 1975 in Okinawa. The number of nonautochthonous cases surpassed that of autochthonous cases in 1992. Nonautochthonous cases originated from 26 countries, particularly Brazil and the Philippines. Three cases of antimicrobial resistance have been detected among nonautochthonous cases since 2004. CONCLUSION: Our data suggest that ongoing transmission of leprosy likely ceased in the 1940s in mainland Japan and in the 1970s in Okinawa. With the recent rise of nonautochthonous cases with globalization, continuous surveillance and efforts to maintain leprosy services within the country are necessary even after reaching the state of elimination.

[Guidelines for the treatment of Hansen's disease in Japan (third edition)].

ad hoc committee of Japanese Leprosy Association recommends revised standard treatment protocol of leprosy in Japan, which is a modification of World Health Organization's multidrug therapy (WHO/MDT, 2010). For paucibacillary (PB) leprosy, 6 months treatment by rifampicin and dapsone (MDT/PB) is enough. However, for high bacterial load multibacillary (MB) leprosy, 12 months treatment seems insufficient. Thus, (A) For MB with bacterial index (BI) > 3 before treatment, 2 years treatment by rifampicin, dapsone and clofazimine (MDT/MB) is necessary. When BI becomes negative and active lesion is lost within 2 years, no maintenance therapy is necessary. When BI is still positive, one year of MDT/MB is added (3 years in total), followed by maintenance therapy by dapsone and clofazimine until BI negativity and loss of active lesions. (B) For MB with BI < 3 or fresh MB (less than 6 months after the onset of the disease) with BI > 3, 1 year treatment by MDT/MB is necessary. When BI becomes negative and active lesion is lost within one year, no maintenance therapy is necessary. When BI is still positive or active lesion is remaining, additional therapy with MDT/MB for one more year is recommended. Brief summary of diagnosis, purpose of therapy, character of drugs, and prevention of deformity is also described.

[Conjugal leprosy infection in Japan--case report and review].

The authors reported a conjugal leprosy infection observed in Japan. The husband, index case, first noticed sensory disturbance at the lower right leg in his forties. He developed edematous swelling with redness of the right hand and forearm at the age of 72 (1989), and then developed multiple erythema and hypesthesia at the extremities. He was diagnosed as BL type leprosy (reactional stage) and treated with multi-drug therapy. His 71-year-old wife developed a few erythema at the right forearm in 1993. She was classified as BT type. The duration of their marriage life was over forty years. The couple did not have consanguinity. No other leprosy patients were found in their lineage. From their clinical courses the authors concluded that the husband infected his wife. According to Japanese literatures, the frequency of conjugal leprosy among new patients in Japan was approximately 1%. There were worldwide observations that the husband often infected the wife, and mostly the index case was multibacillary and the secondary case paucibacillary. The authors reviewed definition and frequency of conjugal leprosy, factors in conjugal infection and leprosy infection among the adults.

[Japanese guideline on thalidomide usage in the management of erythema nodosum leprosum].

Treatment of erythema nodosum leprosum (ENL, type 2 reaction) using thalidomide provides effective alternative choice to steroid therapy. Yet, the Japanese National Health Insurance approves thalidomide prescription only for the treatment of multiple myeloma under the Thalidomide Education and Risk Management System (TERMS). Benefit of thalidomide therapy for patients with ENL is already an established fact based on various reports from other countries, but limited experiences and standards in Japan have hindered application of the medication to our patients. This led us to compose a local guideline. Based on and following the TERMS, we suggest starting thalidomide from 50-100 mg/day and then onwards adjusting the dose according to the symptoms of each patient, not to exceed the maximum recommended dose of 300 mg/day, for the treatment of ENL.

[Genetic involvement of bacterial sensor molecules in Japanese leprosy].

Occurrence of new patients of leprosy, caused by Mycobacterium leprae infection, is now almost absent in Japan but is still uncontrolled in developing countries. As one factor affecting the disease development, genetic predisposition of a host has been considered to be associated. Actually, various gene mutations have been reported to be associated at two stages of the disease progression, not only establishment of the disease but also determination of the phenotype, such as lepromatous (L)-type, tuberculoid (T)-type and reversal reaction. On the basis of recent progress of the research on innate immunity, here we analyzed single nucleotide polymorphisms (SNPs) of the genes of major bacterial sensor molecules expressed in antigen-presenting cells, TLR2, DC-SIGN, NOD1 and NOD2, in Japanese leprosy patients. As a result, frequency of polymorphisms in DC-SIGN -336 showed significant difference between the leprosy patients and the healthy controls, reflecting its role in establishment of the disease. Especially, among those with a particular TLR2 -16934 genotype, frequency of the polymorphisms in DC-SIGN -336 showed significant difference between the patients and the controls, suggesting any cooperation of these SNPs.

[Drug resistance of multibacillary leprosy patients in Japan--results of molecular genetic analyses].

UNLABELLED: Gene mutation of Mycobacterium leprae was studied on bacilli-positive multibacillary leprosy patients since 2000 in Japan. SUBJECTS: LL 31 cases, BL 7 cases. RESULTS: gene mutation of folP was found in 19/36 cases (52.8%), that of rpoB in 13/33 cases (39.4%), that of gyrA in 6/31 cases (16.8%). Five cases showed both mutations of folP and rpoB, and one case showed those of fol/P and gyrA. Mutations of folP, rpoB andgyrA all were found in 4/36 cases (10.3%). High incidence of resistance to DDS or rifampicin was observed, and incidence of resistance to of loxacin was considerably high. These results reveal existence of multidrug-resistant bacilli in Japanese leprosy patients. Treatment of these cases was arranged according to the result of gene mutation analysis and satisfactory effects were obtained in 34/38 cases. One case did not response to newer treatment. Three cases refused use of improved treatment and their disease activities are not controlled. This study proved that gene mutation analysis is a rapid and accurate method to know the drug resistance against DDS, rifampicin and new quinolones, and important in chemotherapy of leprosy.

[Long-term follow-up of ofloxacin-combined therapy for leprosy patients].

This reports a long-term follow-up study on clinical effects of ofloxacin (OFLX)-combined therapy to 14 leprosy patients with various types and stages. Combined drugs were diaminodiphenyl sulfone (DDS), rifampicin (RFP) and clofazimine. Clinical evaluation of the treatment after OFLX-combined therapy was remarkable improvement 10 cases, improvement 3 and re-exacerbated after improvement 1 to whom clofazimine and minocycline were prescribed. The evaluation during the follow-up was remarkable improvement 10, improvement 1; three cases died of traffic accident or complications not related to chemotherapy and none of them showed relapse of leprosy. Bacterial negativity after onset of OFLX-combined therapy was achieved in about the same periods as RFP-combined therapy. OFLX-combined therapy was effective and safe. This follow-up study supports the efficacy of clinical guideline for the use of new quinolones published by Japanese leprosy Association.

[Guideline for the treatment of Hansen's disease in Japan (Second edition)].

ad hoc committee of Japanese Leprosy Association recommends revised standard treatment protocol of leprosy in Japan, which is a modification of World Health Organization's multidrug therapy (WHO/MDT, 1997). For paucibacillary (PB) leprosy, 6 months treatment by rifampicin and dapsone (MDT/PB) is enough. However, for high bacterial load multibacillary (MB) leprosy, 12 months treatment seems insufficient. Thus, (A) For MB with bacterial index (BI) > or = 3 before treatment, 2 years treatment by rifampicin, dapsone and clofazimine (MDT/MB) is necessary. When BI become negative and active lesion is lost within 2 years, no maintenance therapy is necessary. When BI is still positive, one year of MDT/MB is added (3 years in total), followed by maintenance therapy by dapsone and clofazimine until BI negativity and loss of active lesions. (B) For MB with BI < 3 or fresh MB (less than 6 months after the onset of the disease) with BI > or = 3, 1 year treatment by MDT/MB is necessary. When BI become negative and active lesion is lost within one year, no maintenance therapy is necessary. When BI is still positive or active lesion is remaining, additional therapy with MDT/MB for one more year is recommended. This is a simplification of first version in 2000. Brief summary of diagnosis, purpose of therapy, character of drugs, and prevention of deformity is also described.

[Guideline for the treatment of leprosy by new quinolones].

Ofloxacin(OFLX) is often applied today as a substitution drug of MDT for drug resistance to dapsone, rifampicin or clofazimine. However, OFLX resistance is also becoming a great concern. Low and/or irregular administration are considered to be the major causes of OFLX resistance. OFLX should be used as a combined therapy, and minimal daily dose of 400 mg of OFLX or 200-300 mg of levofloxacin is required. Quinolone resistance should be considered when no improvement of clinical and/or bacterial index is observed after the treatment for 6 months. In such cases, resistance gene detection is necessary.

[Consequences of leprosy in the skin].

This summarizes a variety of impairments found in healed leprosy patients. Visible impairments and some secondary complications are presented from the viewpoint of dermatology. Neural damage may bring neuralgia, paraesthesia and progressive neuropathy after healing of leprosy itself.

[A case of Hansen's disease seen in an Indonesian resident, and tracing of the patient after coming back to Indonesia].

A 26-year-old Indonesian male living in Japan consulted our hospital with complaint of fever, general malaise and infiltrative erythematous plaques associated with lymph node swelling. Physical examination revealed a sensation disorder in the distal portion of the extremities and hypertrophy of peripheral nerves. Histopathology of the skin lesion showed the multifocal granulomatous inflammation containing many acid-fast bacilli associated with infiltration of foam cells and neutrophils. Under the diagnosis of leprosy (LL type) accompanied by erythema nodosum leprosum, the combined chemotherapy (clofazimine, rifampicin, and diphenyl sulfone) was started. For the leprosy reaction, short-term administration of the systemic steroid was added. The general condition was carried out soon, and the sensation disorder has also been gradually improved. The patient came back to Indonesia after 6 months treatment because of the time limit of visa. We traced the patient's condition through personal networks, and knew that the patient could not have continual treatment for the disease, and that he is suffering from disability of hands and feet. In this case, several medical facilities were consulted before the final diagnosis of leprosy. The Japanese medical doctors should also remember this disease when they examine persons with infiltrative skin eruptions and sensation disorders.

[Survey of newly diagnosed leprosy patients in Japan (1993-2000)].

We analyzed the medical and social problems of newly registered leprosy patients in the past 8 years from 1993 to 2000 in a low endemic country, Japan. There were 56 registered Japanese patients (males, 32; females, 24), and 76 registered foreign patients (males, 56; females, 20). The number of Japanese patients in each year was between 5 and 9, and 2/3 of them were from Okinawa Prefecture, located in subtropical zone. But the number of foreign patients in each year was between 5 and 18, and 2/5 of them were from Brazil. The number of foreign patients was greater than that of Japanese patients. Male/female ratio has decreased among the Japanese.

[Clinical cure of leprosy--a criteria in Japan(2002)].

In Japan, a cautious definition of clinical cure of leprosy has been used since 1988. This report presents a new definition of clinical cure for leprosy patients after multi-drug treatment is completed. When the patients complete the standard treatment published in 2000, they are defined as "clinically cured". The doctor in charge should inform the patient of the cure of the disease clearly. On the release from the treatment, it is important to explain necessary cares for protection against injuries and prevention from deformities. The patient should be careful about signs of relapse and reactions.