1 / 29

Leprosy

Leprosy. Nadine Chase & Priyanka Patel. Taxonomy. Genus: Mycobacterium Family: Mycobacteriaceae Mycobacterium Leprae Acid-fast Bacillus Gram Positive Bacillus shape Single arrangement Aerobic Optimum growth temperature is 30° Trivia Can not be grown in culture.

kirti
Télécharger la présentation

Leprosy

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Leprosy Nadine Chase & Priyanka Patel

  2. Taxonomy • Genus: Mycobacterium • Family: Mycobacteriaceae • Mycobacterium Leprae • Acid-fast Bacillus • Gram Positive • Bacillus shape • Single arrangement • Aerobic • Optimum growth temperature is 30° • Trivia • Can not be grown in culture http://asylumeclectica.com/asylum/malady/archives/leprosy/leprosy4.jpg

  3. Sehgal, Alfica. Leprosy, Deadly Diseases and Epidemics. Philadelphia, PA, 2006.

  4. Sehgal, Alfica. Leprosy, Deadly Diseases and Epidemics. Philadelphia, PA, 2006.

  5. Types • Tuberculoid Leprosy • Pauci-bacillary (PB) Leprosy • Well defined skin lesions that are numb • 1-5 skin lesions • Lepromatous Leprosy • Multi-bacillary (MB) Leprosy • Chronically stuffy nose • Many skin lesions and nodules • >5 skin lesions

  6. Target Tissues • Skin tissue • Peripheral nerves • Mucus membranes • Bacteria prefers outer cooler parts of the body Sehgal, Alfica. Leprosy, Deadly Diseases and Epidemics. Philadelphia, PA, 2006.

  7. Ecology • Widespread organism living in water and food sources • Obligate Parasites (cannot live independently) • Fish • Insects

  8. Infection Process • Not very contagious • Air born disease • Droplets discharged from the respiratory tract • Nasal secretions • Prolonged contact with excretions from lesions • Slow replication time • Long incubation period

  9. Infection process cont. • Affinity for macrophages and Schwann cells • In Schwann cell • Mycobacterium binds to the G domain of alpha chain of laminin 2 in the basal lamina • Stimulates cell mediated immune response which causes swelling, chronic inflammatory response • Ultimately leads to axonal (nerve) death http://www.med.nyu.edu/news_and_views/images/leprosy.jpg

  10. Nerve cell Normal Nerve Cell Nerve Cell enlargement Arnold, Harry. Modern Concepts of Leprosy. Springfield, IL, 1953.

  11. Preventative Measures • Avoid contact with infected persons • 99% of the population have natural immunity http://www.ruggedelegantliving.com/journal/images/2003/05/01/sars.mask.jpg

  12. Symptoms • Long incubation period • Skin lesions with decreased sensitivity • Numbness • Muscle weakness • Cosmetic Disfiguration • Death is usually caused by a secondary opportunistic disease http://www.wrongdiagnosis.com/l/leprosy/deaths.htm

  13. Diagnostic Test • Leprosy Skin Test • Inactive Leprosy-causing bacteria injected into skin • Body will react to the Leprosy antigens • Check injection 3 days and 28 days later • Positive skin reaction is seen in Tuberculoid Leprosy only • Normal result: little to no skin irritation around injection site http://www.nlm.nih.gov/medlineplus/ency/article/003383.htm

  14. Diagnostic Test: Skin Biopsy • Shave Biopsy • Least invasive • Superficial layers of lesion scraped off • No stitches required • Bacteria can be identified on a slide http://www.nlm.nih.gov/medlineplus/ency/article/003383.htm

  15. Diagnostic Test: Skin Biopsy • Punch Biopsy • Small cylinder of skin removed • Sizes vary depending on size of lesion • May require stitches http://www.nlm.nih.gov/medlineplus/ency/article/003383.htm

  16. Diagnostic Test: Skin Biopsy • Excisional Biopsy • Local anesthetic applied • Entire lesion is removed • Stitches are usually needed http://www.nlm.nih.gov/medlineplus/ency/article/003383.htm

  17. Diagnostic Test: • Methacholine sweat testing • An intradermal injection of methacholine demonstrates the absence of sweating in leprous lesions. • Helpful to identify diagnosis when lesions are not visible on dark skin individuals Arnold, Harry. Modern Concepts of Leprosy. Springfield, IL, 1953.

  18. Treatments • Multi-drug therapy • PB Leprosy • Two Drugs: Rifampicin and Dapsone for 6 months • MB Leprosy • Three Drugs: Rifampicin, Dapsone, Clofazimine for 12 months http://www.nlm.nih.gov/medlineplus/ency/article/003383.htm

  19. Sehgal, Alfica. Leprosy, Deadly Diseases and Epidemics. Philadelphia, PA, 2006.

  20. Treatments cont. • Special Footwear to prevent foot ulcers Grunberg, E., Babger, LF, et al. Leprosy. New York, 1951.

  21. Epidemiology • Age • Children are more susceptible • Bimodal age distribution with peaks at ages 10-14 and 35-44 with higher susceptibilities in younger years • Sex • Higher infection rate in males compare to females • Ratio of infection is 2:1

  22. Epidemiology cont. • Race • African blacks are highly susceptible to the tuberculoid form of leprosy • Caucasians and Chinese are more susceptible to the lepromatous type of Leprosy • Its more rural than urban disease in Asia and Pacific Basin

  23. http://tmcr.usuhs.mil/tmcr/chapter34/large34/34-01.jpg

  24. Morbidity and Mortality • 2002 Data • 1,000 deaths in North and South America • 96 cases in the U.S • 3,000 deaths in South East Asia • 1,000 death in Eastern Mediterranean • 1,000 deaths Western Pacific • 2005 Data • 166 new cases were reported in U.S. • 60% of these cases occurred in: • California • Louisiana • Massachusetts • New York • Texas

  25. HANSEN DISEASE (LEPROSY) Number of reported cases, by year United States, 1973-2003 www.cdc.gov/epo/dphsi/annsum/2003/slides/hansgraf.ppt

  26. Research • Attempt to identify new drugs that can stop the neural damage caused by the bacteria • Bacteria needs to recognize certain type glycoprotein on the cell surface to bind with and subsequently enter the cell • If these glycoprotein can be identified and a drug can interfere with the binding between the bacterium and the protein, this could potentially prevent entry of the bacteria and stop neural damage

  27. A Twin Study • Leprosy has been found to NOT be hereditary • If twin siblings become infected, the disease is passed from one to the other solely because of the proximity in which they live • Twin A acquired the disease at age 15 • Twin B at age 19 • The disease effects the twins differently

  28. Twin Study Twin A Twin B Chakravartti, M.R. and Vogel, F. A Twin Study on Leprosy. Germany, 1973.

  29. References Arnold, Harry. Modern Concepts of Leprosy. Springfield, IL, 1953. Chakravartti, M.R. and Vogel, F. A Twin Study on Leprosy. Germany, 1973. Grunberg, E., Babger, LF, et al. Leprosy. New York, 1951. http://www.cdc.gov/ncidod/dbmd/diseaseinfo/hansens_t.htm http://www.nlm.nih.gov/medlineplus/ency/article/003383.htm http://tmcr.usuhs.mil/tmcr/chapter34/large34/34-01.jpg http://www.wrongdiagnosis.com/l/leprosy/deaths.htm “Leprosy. “eMedicine from webmed. http://www.sunysccc.edu/academic/mst/microbes/16mlepr.htm 21 July 2007. “Leprosy, The Disease” World Health Organization; Regional Office for Southeast Asia.www.searo.who.int/En/Section10/section20/section57_8963.htm. 22 December 2006. Sehgal, Alfica. Leprosy, Deadly Diseases and Epidemics. Philadelphia, PA, 2006.

More Related