Clinics in Dermatology (2015) 33, 1–2
Commentary
Leprosy—An intriguing disease On February 28, 1873, the scientific world was shocked when Dr. Armaeur Hansen announced in Bergen, Norway that leprosy was caused directly by bacteria.1 It was no longer hereditary, due to a curse or the result of a sin. Most of his colleagues and physicians elsewhere laughed; however, he was right. Trying to fulfill Koch’s postulates was not successful. Besides an ancient heritage and threatening face, leprosy started to become an intriguing disease to researchers. In this sense, when the advances in medical science are taken into consideration, it is amazing to realize that leprosy in the 21st century still affects large proportions of the world population and that many obscure pathophysiologic mechanisms still remain to be understood.2 Taking this scenario into account, and considering the relevance of leprosy to dermatologists, this issue of Clinics in Dermatology is directed towards contributing to the discussions on the future of leprosy.
Leprosy reconsidered The current issue is divided into three parts: Leprosy in the 21st century, clinical aspects of leprosy, and leprosy in the laboratory.
Leprosy in the 21st century The number begins with a necessary, but critical, glossary to set the stage for establishing the ground work for discussing key concepts and providing uniform definitions presently used in the field of leprosy research, public health, and clinical approaches.3 This is followed by a chapter on the history of leprosy. Far from the usual repetition of well-known information concerning the historical aspects surrounding leprosy, Grzybowski et al explore in an innovative way the evolution of the disease relating to its etiologic concepts.4 Richardus’s chapter addresses an old and still highly controversial aspect of leprosy control, chemoprophylaxis. With the continued transmission of the disease in endemic countries, a mass preventive measure, such as chemoprophylaxis and http://dx.doi.org/10.1016/j.clindermatol.2014.10.002 0738-081X/© 2015 Elsevier Inc. All rights reserved.
immunoprophylaxis seems opportune, for an effective vaccine for leprosy is lacking. Richardus presents the rationale of these control measures and advocates the use of preventive interventions, utilizing chemoprophylaxis and immunoprophylaxis. In fact, modeling studies have shown that both interventions may reduce the incidence of leprosy in the population.5
Clinical aspects of leprosy The clinical presentation of leprosy is florid and ample. Being a spectral disease, clinical features range from a small single hypopigmented skin patch to a massive inflammatory involvement of the eyes, palate, spleen, liver, testis, bones, joints, peripheral nerves trunks, and skin during immunologic mediated reactions. Clinical manifestations of leprosy are not only part of the portfolio of dermatologists, but also relevant for ophthalmologists, otolaryngologists, general surgeons, and, of course, neurologists. In this regard, the chapters in this section explore the variety of approaches for a single disease. The basic and essential clinical concepts and characteristics of the disease are well documented and extensively discussed by Penna et al.6 The expressive and peculiar aspects of the pathology of the disease are covered by Massone and associates with sound knowledge of the theme and impressive photographic documentation.7 Perhaps, the paramount feature of leprosy is the involvement of peripheral nerves. Once inside nerves, Mycobacterium leprae are ingested by Schwann cells, with a wide array of consequences. Schollard’s contribution on mechanisms of nerve damage in leprosy approaches in detail this relevant, although still obscure, and intriguing hallmark of the disease.8 Leprosy, as a noncurable disease, was one of the pillars of the stigma attached to the disease and those affected by it in past centuries. A new era arose in the early 1940s with the introduction of dapsone, which proved effective as a bacteriostatic agent against the M leprae. The long treatment required and lack of compliance led to the onset of a resistant organism. New drugs and schemes were proposed since then. Kar and Gupta address the important issue of the therapeutics of leprosy with their acknowledged expertize in this field.9
2
Commentary
Lucio’s leprosy is a well-defined and special clinical form of polar lepromatous leprosy that has a special type of lepra reaction. Histopathologically, it corresponds with necrotizing vasculitis and thrombosis. It was named Lucio’s phenomenon or necrotizing erythema by Latapi in 1936. Jurado et al review this fascinating concept.10 Highly neglected, even among physicians dealing with leprosy, eye involvement is extensively described and illustrated by Grzybowski et al. Imagine losing sensation in the hands and feet and then becoming blind.11
Leprosy in the laboratory The final group of papers addresses the laboratory aspects of leprosy, focusing on the most recent advances of science in the fields of immunology, genetics, and experimental leprosy. Nath covers the basic concepts of immunology as applied to leprosy as an immunologic disease,12 while Mira and associates reveal the findings of genetics in leprosy, a science that has just recently approached leprosy as a target for study.13 In the final chapter, Truman addresses one of the most intriguing aspects of leprosy: The difficulty to replicate the disease in experimental conditions. The armadillo is susceptible to experimental infection with M leprae and brings new hope to many studies that were so far difficult or impossible to conduct because of the lack of a reliable animal model.14 Marcos Virmond, MD, PhD Division of Rehabilitation Instituto Lauro de Souza Lima Rod Cmt Joao R Barros Km 226 Bauru – SP, 17034-971, Brazil E-mail address: [email protected]
Andrzej Grzybowski, MD, PhD Department of Ophthalmology Poznan City Hospital, ul., Szwajcarska 3 61-285 Poznań, Poland E-mail address: [email protected]
References 1. Irgens LM. Hansen, 150 years after his birth, the context of a medical discovery. Int J Lepr Other Mycobact Dis. 1992;60:466-469. 2. Virmond M. Foreword. In: Nunzi E, Massone C, eds. Leprosy—A Practical Guide. Italy: Springer; 2012. p. vii-viii. 3. Virmond M, Grzybowski A, Virmond L. Leprosy: A glossary. Clin Dermatol. 2014;33:8-18. 4. Grzybowski A, Sak J, Suchodolska E, Virmond M. Lepra: Various etiologies from miasma to bacteriology and genetics. Clin Dermatol. 2014;33:3-7. 5. Richardus JH, Oskam L. Protecting people against leprosy: Chemoprophylaxis and immunoprophylaxis. Clin Dermatol. 2014;33:19-25. 6. Talhari C, Talhari S, Penna GO. Clinical aspects of leprosy. Clin Dermatol. 2014;33:16-37. 7. Massone C, Belachew WA, Schettini A. Histopathology of the lepromatous skin biopsy. Clin Dermatol. 2014;33:38-45. 8. Scollard DM, Truman RW, Ebenezer GJ. Mechanisms of nerve injury in leprosy. Clin Dermatol. 2014;33:46-54. 9. Kar HK, Gupta R. Treatment of leprosy. Clin Dermatol. 2014;33:55-65. 10. Jurado F, Rodriguez O, Novales J, et al. Lucio’s leprosy, a clinical and therapeutic challenge. Clin Dermatol. 2014;33:66-78. 11. Grzbowski A, Nita M, Virmond M. Ocular leprosy. Clin Dermatol. 2014;33:79-89. 12. Nath I, Saini C, Valluri VL. Immunology of human leprosy and diagnostic challenges. Clin Dermatol. 2014;33:90-98. 13. Sauer MED, Salomão H, Ramos GB, et al. Genetics of leprosy: Expected and unexpected developments and perspectives. Clin Dermatol. 2014;33:99-107. 14. Balamayooran G, Pena M, Sharma R, Truman RW. The armadillo as an animal model and reservoir host for Mycobacterium leprae. Clin Dermatol. 2014;33:108-115.
Commentary
Leprosy—An intriguing disease On February 28, 1873, the scientific world was shocked when Dr. Armaeur Hansen announced in Bergen, Norway that leprosy was caused directly by bacteria.1 It was no longer hereditary, due to a curse or the result of a sin. Most of his colleagues and physicians elsewhere laughed; however, he was right. Trying to fulfill Koch’s postulates was not successful. Besides an ancient heritage and threatening face, leprosy started to become an intriguing disease to researchers. In this sense, when the advances in medical science are taken into consideration, it is amazing to realize that leprosy in the 21st century still affects large proportions of the world population and that many obscure pathophysiologic mechanisms still remain to be understood.2 Taking this scenario into account, and considering the relevance of leprosy to dermatologists, this issue of Clinics in Dermatology is directed towards contributing to the discussions on the future of leprosy.
Leprosy reconsidered The current issue is divided into three parts: Leprosy in the 21st century, clinical aspects of leprosy, and leprosy in the laboratory.
Leprosy in the 21st century The number begins with a necessary, but critical, glossary to set the stage for establishing the ground work for discussing key concepts and providing uniform definitions presently used in the field of leprosy research, public health, and clinical approaches.3 This is followed by a chapter on the history of leprosy. Far from the usual repetition of well-known information concerning the historical aspects surrounding leprosy, Grzybowski et al explore in an innovative way the evolution of the disease relating to its etiologic concepts.4 Richardus’s chapter addresses an old and still highly controversial aspect of leprosy control, chemoprophylaxis. With the continued transmission of the disease in endemic countries, a mass preventive measure, such as chemoprophylaxis and http://dx.doi.org/10.1016/j.clindermatol.2014.10.002 0738-081X/© 2015 Elsevier Inc. All rights reserved.
immunoprophylaxis seems opportune, for an effective vaccine for leprosy is lacking. Richardus presents the rationale of these control measures and advocates the use of preventive interventions, utilizing chemoprophylaxis and immunoprophylaxis. In fact, modeling studies have shown that both interventions may reduce the incidence of leprosy in the population.5
Clinical aspects of leprosy The clinical presentation of leprosy is florid and ample. Being a spectral disease, clinical features range from a small single hypopigmented skin patch to a massive inflammatory involvement of the eyes, palate, spleen, liver, testis, bones, joints, peripheral nerves trunks, and skin during immunologic mediated reactions. Clinical manifestations of leprosy are not only part of the portfolio of dermatologists, but also relevant for ophthalmologists, otolaryngologists, general surgeons, and, of course, neurologists. In this regard, the chapters in this section explore the variety of approaches for a single disease. The basic and essential clinical concepts and characteristics of the disease are well documented and extensively discussed by Penna et al.6 The expressive and peculiar aspects of the pathology of the disease are covered by Massone and associates with sound knowledge of the theme and impressive photographic documentation.7 Perhaps, the paramount feature of leprosy is the involvement of peripheral nerves. Once inside nerves, Mycobacterium leprae are ingested by Schwann cells, with a wide array of consequences. Schollard’s contribution on mechanisms of nerve damage in leprosy approaches in detail this relevant, although still obscure, and intriguing hallmark of the disease.8 Leprosy, as a noncurable disease, was one of the pillars of the stigma attached to the disease and those affected by it in past centuries. A new era arose in the early 1940s with the introduction of dapsone, which proved effective as a bacteriostatic agent against the M leprae. The long treatment required and lack of compliance led to the onset of a resistant organism. New drugs and schemes were proposed since then. Kar and Gupta address the important issue of the therapeutics of leprosy with their acknowledged expertize in this field.9
2
Commentary
Lucio’s leprosy is a well-defined and special clinical form of polar lepromatous leprosy that has a special type of lepra reaction. Histopathologically, it corresponds with necrotizing vasculitis and thrombosis. It was named Lucio’s phenomenon or necrotizing erythema by Latapi in 1936. Jurado et al review this fascinating concept.10 Highly neglected, even among physicians dealing with leprosy, eye involvement is extensively described and illustrated by Grzybowski et al. Imagine losing sensation in the hands and feet and then becoming blind.11
Leprosy in the laboratory The final group of papers addresses the laboratory aspects of leprosy, focusing on the most recent advances of science in the fields of immunology, genetics, and experimental leprosy. Nath covers the basic concepts of immunology as applied to leprosy as an immunologic disease,12 while Mira and associates reveal the findings of genetics in leprosy, a science that has just recently approached leprosy as a target for study.13 In the final chapter, Truman addresses one of the most intriguing aspects of leprosy: The difficulty to replicate the disease in experimental conditions. The armadillo is susceptible to experimental infection with M leprae and brings new hope to many studies that were so far difficult or impossible to conduct because of the lack of a reliable animal model.14 Marcos Virmond, MD, PhD Division of Rehabilitation Instituto Lauro de Souza Lima Rod Cmt Joao R Barros Km 226 Bauru – SP, 17034-971, Brazil E-mail address: [email protected]
Andrzej Grzybowski, MD, PhD Department of Ophthalmology Poznan City Hospital, ul., Szwajcarska 3 61-285 Poznań, Poland E-mail address: [email protected]
References 1. Irgens LM. Hansen, 150 years after his birth, the context of a medical discovery. Int J Lepr Other Mycobact Dis. 1992;60:466-469. 2. Virmond M. Foreword. In: Nunzi E, Massone C, eds. Leprosy—A Practical Guide. Italy: Springer; 2012. p. vii-viii. 3. Virmond M, Grzybowski A, Virmond L. Leprosy: A glossary. Clin Dermatol. 2014;33:8-18. 4. Grzybowski A, Sak J, Suchodolska E, Virmond M. Lepra: Various etiologies from miasma to bacteriology and genetics. Clin Dermatol. 2014;33:3-7. 5. Richardus JH, Oskam L. Protecting people against leprosy: Chemoprophylaxis and immunoprophylaxis. Clin Dermatol. 2014;33:19-25. 6. Talhari C, Talhari S, Penna GO. Clinical aspects of leprosy. Clin Dermatol. 2014;33:16-37. 7. Massone C, Belachew WA, Schettini A. Histopathology of the lepromatous skin biopsy. Clin Dermatol. 2014;33:38-45. 8. Scollard DM, Truman RW, Ebenezer GJ. Mechanisms of nerve injury in leprosy. Clin Dermatol. 2014;33:46-54. 9. Kar HK, Gupta R. Treatment of leprosy. Clin Dermatol. 2014;33:55-65. 10. Jurado F, Rodriguez O, Novales J, et al. Lucio’s leprosy, a clinical and therapeutic challenge. Clin Dermatol. 2014;33:66-78. 11. Grzbowski A, Nita M, Virmond M. Ocular leprosy. Clin Dermatol. 2014;33:79-89. 12. Nath I, Saini C, Valluri VL. Immunology of human leprosy and diagnostic challenges. Clin Dermatol. 2014;33:90-98. 13. Sauer MED, Salomão H, Ramos GB, et al. Genetics of leprosy: Expected and unexpected developments and perspectives. Clin Dermatol. 2014;33:99-107. 14. Balamayooran G, Pena M, Sharma R, Truman RW. The armadillo as an animal model and reservoir host for Mycobacterium leprae. Clin Dermatol. 2014;33:108-115.
