Necrotizing erythema nodosumin lepromatous leprosy associated with mixed infection by Mycobacterium lepromatosis and Mycobacterium leprae. Case report

Systematic Review of Hansen Disease Attributed to Mycobacterium lepromatosis

In 2008, bacilli from 2 Hansen disease (leprosy) cases were identified as a new species, Mycobacterium lepromatosis. We conducted a systematic review of studies investigating M. lepromatosis as a cause of HD. Twenty-one case reports described 27 patients with PCR-confirmed M. lepromatosis infection (6 dual M. leprae/M. lepromatosis): 10 case-patients in the United States (7 originally from Mexico), 6 in Mexico, 3 in the Dominican Republic, 2 each in Singapore and Myanmar, and 1 each in Indonesia, Paraguay, Cuba, and Canada. Twelve specimen surveys reported 1,098 PCR-positive findings from 1,428 specimens, including M. lepromatosis in 44.9% (133/296) from Mexico, 3.8% (5/133) in Colombia, 12.5% (10/80) in Brazil, and 0.9% (2/224) from the Asia-Pacific region. Biases toward investigating M. lepromatosis as an agent in cases of diffuse lepromatous leprosy or from Mesoamerica precluded conclusions about clinicopathologic manifestations and geographic distribution. Current multidrug treatments seem effective for this infection.

Epidemiological characteristics of leprosy during the period 2005-2020: A retrospective study based on the Chinese surveillance system

Background

Jiangsu Province is located in the Yangtze River Delta region, with a total area of 107,200 square kilometers. Since 1949, over 55,000 cases have been registered, with Taixing accounting for the highest number of patients. The proportion of new cases with MB and G2D was higher compared to other regions. As a result, Jiangsu has been considered a priority area for public health interventions in China.

Methods

This paper mainly described the population, time, and spatial distribution of the newly detected leprosy cases in Jiangsu Province between 2005 and 2020. In this study, all the data were entered into Microsoft Excel and SPSS for the descriptive analysis. ArcGIS was applied to create statistical maps, and Geoda was used to conduct spatial autocorrelation analysis with local Moran's I statistics (LISA). The epidemiological data were obtained from LEPMIS. In addition, population data were obtained from the Statistical Yearbook of Jiangsu Province.

Results

During the study period, 363 new cases were reported. Of these, 232 were men and 131 were women (1.77:1). The mean age at diagnosis was 60.56 years, and no adolescent cases were identified. Three hundred and twenty-seven (90.08%) were diagnosed with MB and 36 (9.92%) with PB. 31.68% (115/363) of the patients presented with G2D. Farmers accounted for 74.9%, and most cases were identified in skin clinics (248, 68.32%). We observed a decreasing trend in detection rate, with a higher concentration of new cases diagnosed between July and October. Spatial analysis showed that the new cases were primarily distributed in the northwest of Jiangsu province, and Suqian has the highest incidence of leprosy. Special attention should be paid to Wuzhong, a county with a potential risk of inter-provincial transmission. Furthermore, 55 new cases came from other Chinese provinces but lived in Jiangsu.

Conclusion

The NCDR of leprosy decreased, but the new cases showed disabilities, a sign of the late diagnosis. The results indicated that some regions were still suffering from the burden of leprosy. Thus, we recommend that the government should adopt effective strategies to promote leprosy control. The main priorities for eliminating new cases were to provide sustainable financial support, improve the quality of clinical services, strengthen preventive intervention and rehabilitation services for disabilities, provide health education among high-risk populations, and explore new approaches.

Leprosy Caused by Mycobacterium lepromatosis

OBJECTIVES

Leprosy is caused by Mycobacterium leprae or Mycobacterium lepromatosis. This study reviews literature on M lepromatosis and reports on a Mexican family with this infection.

METHODS

The review included all primary studies. Family history and surveys were used to uncover the infection cluster. Genome-based differential polymerase chain reactions were designed to detect etiologic agents.

RESULTS

Since the discovery of M lepromatosis in 2008, 154 cases of M lepromatosis infection from 11 countries in the Americas and Asia have been reported, with most cases coming from Mexico. These cases included diffuse lepromatous leprosy (DLL) and other leprosy forms. Genomes of M lepromatosis strains have lately been sequenced, revealing 3,271,694 nucleotides and approximately 15% mismatches with M leprae. The Mexican family with leprosy involved the grandfather, mother, and 2 grandsons. The index was the oldest grandson, who manifested DLL and likely contracted the infection from his maternal grandfather approximately 13 years earlier. Family surveys diagnosed DLL in the index patient's mother and borderline leprosy in his brother; both were likely infected by the index patient. M lepromatosis was identified from archived biopsies from the index patient and his mother, while M leprae was excluded.

CONCLUSIONS

M lepromatosis is a significant cause of leprosy in Mexico and requires better surveillance and control.

Mycobacterium leprae and Mycobacterium lepromatosis infection. A report of six multibacillary cases of leprosy in Dominican Republic

The causative agents of leprosy are Mycobacterium leprae and Mycobacterium lepromatosis. M. lepromatosis was found in 2008 to cause diffuse lepromatous leprosy in Mexican patients. The objective of this work was to identify M. leprae and M. lepromatosis in paraffin-embedded skin samples from Caribbean leprosy patients. A total of 6 skin samples were obtained from the Dominican Republic. All cases presented the multibacillary form; 5 cases were nodular lepromatous leprosy, and 1 case was borderline lepromatous leprosy. All patients received multidrug therapy. Molecular identification was achieved using the M. leprae-specific repetitive element (RLEP) for M. leprae and the hemN gene for M. lepromatosis. Mycobacterium leprae was identified in two lepromatous leprosy cases and 1 borderline lepromatous leprosy case; M. lepromatosis was found in 1 nodular lepromatous leprosy case. Both Mycobacterium species were present in two nodular lepromatous leprosy cases. This is the first report of M. lepromatosis in the Dominican Republic.

Mycobacterium lepromatosis as a Second Agent of Hansen's Disease

Mycobacterium lepromatosis was identified as a new species and second causal agent of Hansen's disease (HD, or leprosy) in 2008, 150years after the disease was first attributed to Mycobacterium leprae. M. lepromatosis has been implicated in a small number of HD cases, and clinical aspects of HD caused by M. lepromatosis are poorly characterized. HD is a recognized zoonosis through transmission of M. leprae from armadillos, but the role of M. lepromatosis as a zoonotic agent of HD is unknown. M. lepromatosis was initially associated with diffuse lepromatous leprosy, but subsequent case reports and surveys have linked it to other forms of HD. HD caused by M. lepromatosis has been reported from three endemic countries: Brazil, Myanmar, and Philippines, and three non-endemic countries: Mexico, Malaysia, and United States. Contact with armadillos in Mexico was mentioned in 2/21 M. lepromatosis HD case reports since 2008. M. lepromatosis in animals has been investigated only in non-endemic countries, in squirrels and chipmunks in Europe, white-throated woodrats in Mexico, and armadillos in the United States. To date, there have only been a small number of positive findings in Eurasian red squirrels in Britain and Ireland. A single study of environmental samples found no M. lepromatosis in soil from a Scottish red squirrel habitat. Future studies must focus on endemic countries to determine the true proportion of HD cases caused by M. lepromatosis, and whether viable M. lepromatosis occurs in non-human sources.