Leprosy is caused by a bacteria very similar to tuberculosis called Mycobacterium leprae. Like Mycobacterium tuberculosis, it has an extremely long doubling time (the amount of time it takes for the bacteria to divide), but unlike M. tuberculosis, it lacks many key enzymes for extra cellular growth and has thus far only been cultured using living media. Most laboratories use immune compromised mice, but a few use armadillo foot pads, because weirdly enough, it has been found in armadillos. Funny aside about this, Karigiri brought in an armadillo from louisiana to see how they could use it in their research, but it died in like three days...poor armadillo...Coming from America to the sweltering Indian April heat was just too much... I think I'll have another sip of water.
The bacteria doesn't grow so well at 98.6, much preferring several degrees below that. This may lead many of you to shout, "why doesn't it just leave us the hell alone?! Well it developed a nasty way around this; it infects in the periphery, the more peripheral the better, striking the fingers and toes most often, but not uncommonly moving to the face and respiratory tract.
In these places it infects nerve cells, and it grows and multiplies inside the cells. How it gets there is still something of a mystery, but the most current research points to the skin or respiratory tract as the most likely culprits, not through sexual contact as was previously believed (another interesting aside, it is now thought that many of the ancient cases of leprosy may have been syphilis, which was transmitted sexually and can lead to similar impairments) However, leprosy is very, very poorly contagious, and very few of those even in very close, intimate contact with individuals highly infected will themselves get the disease. It is believed that fewer than 5% of all individuals are capable of becoming infected, and this variation is thought to be due to slight differences in the immune system.
Once infected with the bacteria, your body has a "choice." To describe it, I'll use an analogy. Imagine your kitchen is on fire. Your house looks fine on the outside, still got that white picket fence, nicely coordinated color scheme. If your neighbor walked by they wouldn't notice anything wrong. Inside, however, it is quickly going to hell in a hand basket. You run outside to grab a garden hose to douse the flames and now have a "choice": you can take the hose through the window into the kitchen and put out the fire, or you can turn the hose on outside and just spray the outside of your house to your hearts content.
Sounds like a no brainier right. Jump inside the house, put out the fire for good, then head to Lowe's to improve the resale value (but really, just call the fire department. No heroics). Using the hose on the outside of the house would only really work once the fire finished of the kitchen as well as the rest of the house. Might even have a go at the other houses on your block as well.
This is the choice your immune system has. It can mount a cell mediated response, meaning your body makes seal team six esque cells that find cells infected with M. leprae and destroy them (ok, so not like the hose analogy). Or it makes antibodies, which softly patter on the outside of the cells like ineffectual droplets of water as your nerves are destroyed by the bacteria.
People who mount an antibody only response have more rapid onset and much more damage caused by the bacteria. People who mount a cell mediated response typically have a few hypo pigmented patches on their skin and some sensory loss from the nerve damage, and many will clear the disease on your own. Why your body chooses one root or the other is currently a mystery, but discovering why, and more importantly if can do anything to alter the immune response is likely central to finding a quicker treatment.
Leprosy is treatable with a combination of antibiotics, necessary due to growing resistance especially when only one antibiotic is used. And while the treatment has come a long way, removing the stigma associated with the disease has not. Many people in India are banished from their families once they develop the external manifestations of the disease. The physicians, nurses, social workers and volunteers at karigiri are hard at work to remove this stigma and provide these people with more effective social support.
The bacteria doesn't grow so well at 98.6, much preferring several degrees below that. This may lead many of you to shout, "why doesn't it just leave us the hell alone?! Well it developed a nasty way around this; it infects in the periphery, the more peripheral the better, striking the fingers and toes most often, but not uncommonly moving to the face and respiratory tract.
In these places it infects nerve cells, and it grows and multiplies inside the cells. How it gets there is still something of a mystery, but the most current research points to the skin or respiratory tract as the most likely culprits, not through sexual contact as was previously believed (another interesting aside, it is now thought that many of the ancient cases of leprosy may have been syphilis, which was transmitted sexually and can lead to similar impairments) However, leprosy is very, very poorly contagious, and very few of those even in very close, intimate contact with individuals highly infected will themselves get the disease. It is believed that fewer than 5% of all individuals are capable of becoming infected, and this variation is thought to be due to slight differences in the immune system.
Once infected with the bacteria, your body has a "choice." To describe it, I'll use an analogy. Imagine your kitchen is on fire. Your house looks fine on the outside, still got that white picket fence, nicely coordinated color scheme. If your neighbor walked by they wouldn't notice anything wrong. Inside, however, it is quickly going to hell in a hand basket. You run outside to grab a garden hose to douse the flames and now have a "choice": you can take the hose through the window into the kitchen and put out the fire, or you can turn the hose on outside and just spray the outside of your house to your hearts content.
Sounds like a no brainier right. Jump inside the house, put out the fire for good, then head to Lowe's to improve the resale value (but really, just call the fire department. No heroics). Using the hose on the outside of the house would only really work once the fire finished of the kitchen as well as the rest of the house. Might even have a go at the other houses on your block as well.
This is the choice your immune system has. It can mount a cell mediated response, meaning your body makes seal team six esque cells that find cells infected with M. leprae and destroy them (ok, so not like the hose analogy). Or it makes antibodies, which softly patter on the outside of the cells like ineffectual droplets of water as your nerves are destroyed by the bacteria.
People who mount an antibody only response have more rapid onset and much more damage caused by the bacteria. People who mount a cell mediated response typically have a few hypo pigmented patches on their skin and some sensory loss from the nerve damage, and many will clear the disease on your own. Why your body chooses one root or the other is currently a mystery, but discovering why, and more importantly if can do anything to alter the immune response is likely central to finding a quicker treatment.
Leprosy is treatable with a combination of antibiotics, necessary due to growing resistance especially when only one antibiotic is used. And while the treatment has come a long way, removing the stigma associated with the disease has not. Many people in India are banished from their families once they develop the external manifestations of the disease. The physicians, nurses, social workers and volunteers at karigiri are hard at work to remove this stigma and provide these people with more effective social support.
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