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Video transcript

this is Charles prober and I'm Morgan theis and today we're going to talk about the extra pulmonary disease associated with tuberculosis which I find kind of interesting because I always think of tuberculosis as a lung disease so well in fact you're correct Morgan that the most prominent infection associated with tuberculosis is pulmonary disease is lung disease but extra pulmonary disease is also very important in fact it's so important that we're going to make two videos about extra pulmonary disease the first one we're going to focus on disease involving the lymph nodes and the genital urinary tract and then the second one we're going to talk about involvement of the bones the central nervous system the gastrointestinal tract and the heart and the reason that it's so important to give this much time to extra pulmonary disease is that recall tuberculosis the bug infects one-third of the world's population and after that initial infection some go on and immediately develop disease and others as we talked about before develops secondary disease and it comes out later and the infection may present in a myriad number of ways in fact that's one of the reasons that tuberculosis as roof is referred to as one of the great imitators it can imitate so many other kinds of disease so to videos okay so TB the great imitator exactly I mean some of the other great imitators people talk about these days are lupus which is of course not an infectious disease HIV infection which is an infectious disease epstein-barr virus infection which is a viral infection that those are other great imitators but today we're talking about tuberculosis okay and these are good to remember because since they can present in so many ways we sort of always have to have him on our differential diagnosis so we don't forget about him exactly so the first site that I'm going to talk about Morgan is lymph nodes and I'm talking about that first because it actually is the most common place that TB goes after the lungs okay and which lymph nodes are we talking about because they're everywhere in the body right so that is true they're everywhere in the body and the infection of the lymph nodes can occur anywhere in the body but the most common sites are posterior cervical so behind the lymph nodes be at the back of the neck and then another common site is the supraclavicular area so that space above the clavicle oftentimes when you feel a lymph node above the clavicle you appropriately think of some sort of malignancy in the abdominal area because that's a sentinel node the supraclavicular lymph node but something to remember that can also cause that is tuberculosis one of the features of aloof node infection with tuberculosis is that the lymph nodes tend to be painless so they don't hurt the person and also they tend to be not particularly Ender so when you push on them they also don't hurt the person they often have a lack of overlying redness or heat because there really isn't much of an acute inflammatory response it's more of a chronic slow process so these lymph nodes tend to sneak up on you gradually enlarging as they gradually enlarge some of them however can because it's a long term process can actually cause fistula Strax that is a connection that goes from the lymph node all the way up to the skin with drainage oh gosh so if you see a fistula Streck associated with an enlarged lymph node tuberculosis should be on your list the way these are diagnosed is that a sample of the lymph node may be obtained and when that under the microscope you may actually see the tuberculous bacilli those little red snappers as they're sometimes called or you may culture them if you don't actually see them taking a chest x-ray of patients with suspected TB and the lymph nodes is a good idea right however half the time or more than half the time the chest x-ray is negative so don't be discouraged from the diagnosis if the chest x-ray is negative because it oftentimes is negative got it so the next site that I'd like to talk about is the genital urinary site and I'm talking about this site next because after lymph node involvement comes the so-called GU or genital urinary involvement so to represent maybe 10 or 15% of cases of extra pulmonary TB as opposed to lymph nodes it's more like 35% so this is about half as common as is true of any infection that can involve the genital urinary site the kidneys in the genital area the patients may have very nonspecific complaints such as blood in their urine or pain when they urinate or needing to get up at night to urinate if you examine their urine under the microscope you may actually see white blood cells so pyuria but you don't see any bacteria typically so that can be a finding I I'm confused about that because why wouldn't the bacteria actually be in the urine so the main reason is that the amount of tuberculous bacilli they're often present at one of these extra pulmonary sites is quite small and unless you either centrifuge the urine or otherwise concentrated and stain it with tuberculous specific stains you will not see bacteria that's in contrast to regular bacterial infections of the urinary tract where there is typically hundreds of thousands - even millions of bacteria that show up in the typical stains that are used so the term that's used here is when you see the white cells in urine you don't and you don't see any bacteria and then you culture them for regular bacteria and they don't show up because TB doesn't show up on regular cultures it's culture-negative Peoria so culture negative Peoria should make you think of tuberculosis now if you actually send those urine samples to the lab and say I'm looking for tuberculosis and they're set up on tuberculosis specific media then you often will grow the TB but if you don't think about it you won't do the test and if you don't do the test you won't make the diagnosis you're asking for TB culture exactly I mentioned the chest x-ray in the context of lymph node involvement and it's often negative with genital urinary involvement the chest x-ray is often positive so if you see culture negative pyorrhea and you're thinking of tuberculosis the chest x-ray may have value the other part of the genital urinary infection that I'll mention here is specific to women and it's the tuberculosis may actually involve the internal genitalia of women that is the fallopian tubes and the endometrium and the importance of recognizing that is that this is one of the causes of infertility especially in the developing world where tuberculosis is more common there also men can also get infection of their internal genital organs including epididymis and the testicles they could also have prostate involvement so again tuberculosis can cause an itis and inflammation in multiple organs in this case in the genital urinary area and you say endometriosis is one of them and OB try to say and do it up in women can occur and I mentioned the fallopian tubes and when you have inflammation in those areas that can result in infertility you you