Type I Membranoproliferative Glomerulonephritis (MPGN)

00:00 Type I MPGN. Most common type it is.

00:03 Nephrotic syndrome presentation, what does that mean to you? You begin with protein loss.

00:09 And greater than 3.5 grams of protein per day.

00:11 Hypoalbuminemia and generalized edema.

00:15 You would have loss of antithrombin III, Anticoagulation, maybe a little bit of hypertension.

00:20 That's your nephrotic presentation, isn't it? Some cases it will have nephritic.

00:25 I told you earlier that MPGN and DPGN will have a little bit of nephritic, a little bit of nephrotic.

00:33 Now, most of this with MPGN in fact, is nephrotic.

00:36 Associated with hepatitis C, more common or cryoglobulinemia.

00:42 What does that even mean? That means that you might have conditions and at some point in time, when you get into cryoglobulinemia, there are three different types.

00:51 One, two, and three, cryoglobulinemia.

00:52 The big ones.

00:53 Type I associated with multi-myeloma.

00:57 Type II and III, more or less associated with infections and autoimmune diseases.

01:02 What do all of these have in common? Autoimmune diseases.

01:05 Monoclonal gammopathies and hepatitis C could be put in there as well.

01:10 They are associated with antigen-antibody complexes. Okay.

01:19 Two components, circulating through the body.

01:23 All of a sudden cryo.

01:24 What does that mean? Cold exposure.

01:29 The globulins will precipitate resulting in all kinds of issues in your patient.

01:34 Mostly, what do you know this about Waldenstrom? In Waldenstrom, what then happens when you have your globulins that will precipitate in the blood? It’s almost like a thrombus, isn't it? And so therefore it’s hyperviscosity. Hyperviscosity.

01:52 Cryoglobulinemia is a big deal, a big clinical condition or syndrome, and I've given you a few examples of type I, type II, type III.

02:01 My point at this point though, what kind of MPGN are we dealing with? Type I.

02:07 In the previous discussion what branch of our MPGN would that follow? Immunecomplex mediated or would it be complement-mediated? Good, immune complex mediated. Much more common, type I.

02:23 Which type I? On your light microscopy, can't really tell the difference between type I and type II, that I can tell you for certain.

02:31 However, where you can start seeing differences? When you hear at this point, it should be reflexive.

02:39 When you say subendothelial immune complexes, what kind of biopsy is this? Good. Electron microscopy.

02:46 If you see a granular pattern, what kind of biopsy is that? Good. Immunofluorescence.

02:51 Aren’t you feeling good about this now? You're reading, as if you’re reading a clinical vignette.

02:55 You're reading as if it was a medical journal.

02:56 Lancet, New England’s Journal Of Medicine. Whatever it may be.

02:59 And these are the kind of information that it has and you should be able to- These are the kind of questions, information that everyone expects you to know, at your level of medical education.

03:11 The immune complexes activate classical and alternative complement pathway.

03:16 You know that already.

03:17 Electron microscopy shows tram-track.

03:22 What’s that even mean? Tram-track means, the membranes being involved, membranoproliferative.

03:28 The membranes been involve, what happens? Split of the glomerular basement membrane by ingrowth of mesangium.

03:37 Tram-track, is that specific? No. It’s not.

03:41 Anything that weakens that membrane, do you think that you would then have deposition of mesangium and splitting of it? Sure. Another good differential, Alport Syndrome.

03:51 Hypertension, 35% of the majority of your patients will have hematuria.

03:56 Remember, MPGN? Nephritic/Nephrotic presentation.

03:59 Majority will progress to chronic renal failure.

04:02 Which was most common, type I or type II? Type I.

04:06 If it’s type I, what kind of association? Immune complexes.

04:10 Examples, autoimmune disease, infections such as Hepatitis C and cryoglobulinemia.

04:17 And we have monoclonal gammopathies, including Waldenstrom.

04:21 With type I, response to corticosteroids not established, let it go.