Treatment Regimens for Mycobacterium Tuberculosis – Antimycobacterial Agents

00:00 Okay, now in terms of the actual drug regimens that we're using in TB, here's a standard regimen.

00:08 Isoniazid, rifampin and pyrimethamine.

00:12 Now pyrimethamine is often stopped in a non-HIV patients.

00:15 Alternative regimens maybe isoniazid and rifampin for 9 months.

00:21 Or isoniazid and efambutol for 18 months.

00:25 In patients who have resistance.

00:28 And that resistance is usually to isoniazid.

00:31 We use rifampin, pyrimethamine and ethanamide for 6 months.

00:34 Or rifampin, pyrimethamine and streptomicin for 6 months.

00:38 So this can be a downloadable file so that you can have a look at it on your own.

00:45 I also recommend that you have a look at the treatment regimens for your part of the country or of the world.

00:52 And a really good example of this is the difference between say California and Alaska.

00:57 Or even between the US and Canada.

01:00 So it's interesting to see that the Yukon territory is right next territory to Alaska, they are neighbors.

01:06 And they will have completely different treatment regimens.

01:08 Germany and Poland have different regimens despite being neighbors.

01:12 Look at your own country or your own locations guidelines on TB management because it will be a little bit different.

01:18 Let's look at the treatment of leprosy.

01:22 So treatment of leprosy is with dapsone.

01:25 It is the most active drug against leprosy.

01:28 The oral agent penetrates very, very well.

01:31 And it inhibits folic acid synthesis.

01:34 We use dapsone in combination with rifampin many, many times.

01:39 The toxicity of this medication includes GI irritation, rash, hemolysis.

01:44 Specially hemolysis in people who have gluco 6 phosphotate deficiency.

01:49 Acedapsone is another version of dapsone.

01:54 It's a depot formulation that last for months.

01:57 And we also use this medication in HIV patients to treat certain pneumocystis infections as well.

02:03 Okay, let's move on to atypical microbacterium infections.

02:09 Let's start off with MAC.

02:11 It's also called Microbacterium avium complex or MAC.

02:16 It's also called Lady Windermere syndrome.

02:18 It's seen in HIV positive patients often.

02:22 It's often involved in the right lobe or the right middle lobe.

02:25 Sometimes you see it in the left lingular lobes.

02:28 Now prophylaxis with CD4 counts less than 50, is clarithromycin and -- sorry clarithromycin or azithromycin plus or minus rifabutin.

02:41 With treatment with patients who have CD4 counts less than 50, we have clarithromycin or azithro plus ethambutol, plus rifampin.

02:53 Other atypical microbacteria include microbacteria marinum and microbacteria ulcerons.

02:59 Obviously these two are seen in certain demographics.

03:04 Marinum is often seen in -- we use to call this Fish Workers disease or Fish Worker's ulcers.

03:10 And microbacteria ulcerons are seen in certain diabetic patients with ulcer activity.

03:15 It's often treated with regular antituberculous drugs.

03:20 Now here is a CT scan of a patient with right middle lobe consolidation, secondary to microbacterium avium.