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Current time:0:00Total duration:12:50

Video transcript

this is Charles prober and Morgan theis and we're going to talk on this video about the treatment of active tuberculosis infection and I'll state the obvious up front which is the reason you want to treat somebody with any infectious disease in this case tuberculosis is to prevent disability and death from the infection another reason for treating infectious diseases especially important with TB is to reduce the spread of infection to other individuals the good news about the treatment of active TB infection is that we have a number of drugs which have been developed over time that are really quite effective at treating the infection the bad news is that unlike many infectious diseases these drugs have to be given for a fairly long period of time they usually have to be given in combination so you need multiple drugs to be effective in treating and other bad news is that resistance among strains of tuberculosis is becoming a problem globally and we're going to talk about the treatment of resistant organisms on another video because it in itself is quite complicated but for the purpose of this video we're going to talk about the treatment of active TB and we're going to make the infection the most common variety the one that were most likely to see and want to treat and that's an individual with pulmonary tuberculosis so the first thing is of course we have to diagnose the infection so let's assume that we've done that we know that this person has active TB caused by active TB and they in their lungs and we want to initiate therapy for most individuals the therapy begins with a combination of four drugs this is assuming we don't know that this is a resistant organism and the four drugs we start off with are there's an acronym called ripe or IPE where the R stands for refampin the I stands for isin iessod or inh the P stands for pure is in amide or pza and the e stands for Evangel and we treat the patient with all four drugs right at the outset with the reason for that and it's anticipated to be for a two-month period and the reason for that is we want to blast the infection and eliminate as many of the organisms as possible as quickly as possible so these are powerful anti tuberculous agents first-line agents that are aimed to kill the TB as quickly as possible over that two-month period so we're calling them bacteria settle right there bactericidal organ of antibiotics they kill the TV we confirm that by doing cultures along the way but those are the antibiotics that we start with and that's sort of the intensive phase of therapy at two-month period then if all goes well we back off to just two drugs for the ensuing four months and the two drugs are refampin and I&H and that sort of the consolidation phase of therapy we can use less drugs because we've killed the bulk of the tuberculous organisms hopefully in that first two months and now we're giving consolidated therapy at the end of this therapy which is his typical six month period if all goes well we do a chest x-ray at the end of therapy we determine that the chest x-ray is improved from the first one that led us to the diagnosis and that is the end of therapy okay however there are some patients that actually we end up needing to treat longer because they don't have the simple pulmonary form of the disease or they have some underlying problem so as if six months wasn't long enough you can actually have a longer treatment regimen exactly and sometimes the the things which are or the disorders that are often associated with a longer duration of therapy is if you have more severe disease so for example TB meningitis you would typically treat longer TB infection of the bones and joint you would typically treat longer so-called miliary TB you would treat longer and even pulmonary TB where there's a big cavity in the lung often will be treated longer another circumstance that yields or makes you treat longer is if the patient is co-infected with HIV or if the patient is pregnant a pregnancy creates a certain degree of immunosuppression and pregnant women are treated for longer durations finally patients who cultures remain positive throughout treatment or at least for more than two months into treatment if they remain positive they get treated for a longer period of time and patients who have a resistant organism which we'll talk about at another video get treated for a longer period of time so back to the patient that we're treating just for the regular period of time for that six month interval there are a couple of very important treatment protocols that you need to be aware of as these patients are being managed the first is you one has to make sure that they're taking their drug so that they're compliant with their medication I mean it seems like it'd be pretty hard for a patient to take of all these four medicines and then two medicines every day for six months so exactly and so recognizing that this is a challenge for patients to take multiple medications for multiple months you need to be aware of that challenge and try to make the take you to the medication as easy as possible and make sure that you you're observing that there are taking their medication and let's talk about that observing first this has been a huge benefit in the management of patients with TB recognizing the need the desirability and a benefit for something called directly observed therapy or dot directly observed therapy means exactly what it sounds like a health care provider is making sure the patient is taking their medication the reason that that's so important is that it will yield a higher cure rate if they are taking their medication consistently and less likelihood that they will develop a resistant organism so dot directly observed therapy is very important the other a spell iment of assuring compliance is to make it as easy as possible for the patient to take their medication well one strategy is you can have them take their medication three days a week as opposed to every day and it appears that the treatment is equally effective so under directly observed therapy you can have them take it just three times per week the student that the patients need to be encouraged constantly to take their medication underscoring why it's important that they do so there's some logistic issues that may help assuring compliance for example if you have convenient office hours where the patient can come and see you after their work providing incentives and enablers to patients for taking their Medicaid for example providing them meals or giving them travel vouchers to come into the clinic or to wherever you're seeing them and then there are some strategies for simplifying the regime's I've already mentioned one which is three times a week therapy there are also some combination medications available in some countries that may be valuable in enhancing compliance so while we are busy assuring compliance when we're seeing these patients on a regular basis we're also monitoring to make sure that they're the outcome of their infection is going well and so what that means is that we're evaluating them clinically at regular intervals often every month or so examining them we're also obtaining cultures from their Fitz pulmonary TB from their sputum at monthly intervals to make sure that they become culture negative in the anticipated two or less months if cultures aren't available you can do smears of their culture but it is better to get cultures when they are available and so that's all part of monitoring another important part of monitoring patients who are being treated for tuberculosis is watching for side effects and we'll do those for the ripe again for the four key anti microbials used for treating common T V infections so R again is for refampin and the main side effects to keep in mind about refampin are that it can cause hepatitis and so if a patient develops clinical symptoms and you think maybe hepatitis they get jaundice for example you have to be recognized and rifampin is one possibility another side effect of rifampin is decreased platelet counts that is thrombocytopenia and you need to be aware of that and then a very important side effect of Rafah pen is drug to drug interactions because rifampin is a potent inducer of certain enzymes in the liver site of cytochrome p450 enzymes there can be interactions with other drugs as it aside refampin also may color secretions red like red urine and red tears that make interfere with contact lenses but that's more an annoyance than a significant side effect with regards to eye and age horizon eye is it the main side effects to be familiar with again our hepatitis INH can cause hepatitis especially in those that already have a reason for having hepatitis for example alcoholics and Eisen ayahs it can also cause a peripheral neuropathy oftentimes resulting from vitamin b6 or pyridoxal deficiency so you can take care of that by prescribing periodic scene at the same time that's especially true if the patient has poor nutrition and alcoholic for example you can also get neuropathy in patients with chronic renal who are taking I&H with chronic renal failure and diabetes and so forth but neuropathy is important to keep in mind with regards to peers in abide these individuals may get high uric acid levels and resulting arthralgias they can even get overt gout and that would be a reason for stopping appear as in abide and then finally with regards to a fab you doll patients may develop an optic neuritis which can impair their vision and that would be a reason to stop if an adult their opee so being familiar with these side effects as you monitor the response of the patient to therapy and as you monitor their compliance is also an important part of the treatment of active TB