Rapidly Progressive Glomerulonephritis (rpgn) & Subtypes

00:00 Now, once again, let me make sure we’re clear.

00:03 Two definitions, so that picture that I showed you, light microscopy with crescentic proliferation, remember, that is a syndrome so you could have many, many, many causes that may lead into it.

00:13 Nephritic always is where you’re coming from, tell me about your patient and presentation, hypertension, hematuria, RBC casts, we have many dysmorphic RBC, we have oliguria, and with nephritic is where I’m coming from and how quickly will the kidney die? 12 weeks.

00:31 Now, if you missed this question, I will come out and find you, and slap you silly.

00:34 Twelve weeks is rapid.

00:37 This is not acute renal failure, completely different definition and then, we’ll go into chronic later on.

00:43 Patients present with nephritic, everything we just said, H&E, light microscopy, we’ll show you Bowman’s space which has completely been occupied by crescentic cells which does what? Restricts and compresses the glomerular tuft, prognosis, poor, and go into end stage renal failure really quick.

01:02 Now, with RPGN, there are different types that we’ll talk about.

01:05 Now, it is not important for you to know type one, type two, type three, that’s not what’s important.

01:11 However, what I’d recommend and what we have in medicine is that type one RPGN include these diseases.

01:19 Type two will include more and type three will be even more.

01:23 What I would also do is because it’s impossible in my opinion to memorize everything at one time.

01:29 So what you wanna do is take a look at type one and give yourself an organization pattern, isn’t that much more effective? So type one, RPGN, perhaps it’s anti-glomerular basement membrane disease is what the patient had.

01:42 Who is your patient? Young patient, 20’s maybe, male more likely, and was coughing.

01:51 When coughing, found what? Blood, hemoptysis, also, had hematuria.

01:57 Why? It’s a nephritic, okay.

01:59 Any sinusitis? No.

02:01 Why did I put that in the mix? Sinusitis to you should give you a different diagnosis or have you think about another differential known as, well, once again, you know this being Wegener but now, what is it called? Granulomatosis with polyangiitis, I’ll abbreviate it as being GPA just to make our lives easy, I’m going to keep repeating that until it becomes part of your unconscious reflex.

02:25 Next, what else? It could be idiopathic, it could be, well, as you we said, Goodpasture.

02:31 Under type two, the category is, well, these are causing RPGN.

02:35 With type two, these are immune-complex diseases.

02:39 Let me walk you through this and you tell me where these immune-complex are located on your otomicroscopy.

02:45 Ready? Postreptococcal, postreptococcal infectious glomerulonephritis.

02:50 Where did it come from? Two places, pharynx or skin.

02:56 Give yourself an approximation of two to four weeks.

02:59 Later your child may be perhaps presented with hematuria.

03:04 Remember some of the streptozyme tests and some of them included anti-DNase B that want the skin which is 60% of the time they’ll present with PSGN will come from the skin and at least, give yourself S as in skin, S as in streptokinase being frequently found as being a streptozyme test.

03:24 Next, tell me about the immune-complex, where is it? Use the P to your advantage, subepithelial, good.

03:31 Pattern on immunofluorescence, granular.

03:34 Another one with a deposit, SLE.

03:39 What kind of stain or marker would you find with kidney damage? How many kidneys? Two, anti-double stranded DNA, good.

03:50 What is the prototype that you’d find here with SLE? It’s called DPGN, diffuse proliferative glomerulonephritis.

03:59 How are you gonna use that D for immune-complex? D as in subendothelial, clear? Once again, what kind of pattern on immunofluorescence? Granular, excellent.

04:11 Let’s move on to Henoch-Schonlein purpura, what’s a better name for this? IgA nephropathy? No.

04:19 IgA nephropathy or glomerulopathy is Berger, IgA vasculopathy is Henoch-Schonlein.

04:28 How can you make that differentiation? What does purpura mean to you? Damaged blood vessel, fibronoid necrosis, bleeding, purpura, IgA vasculopathy.

04:40 Are all of these dealing with immune-complexes? Sure they are.

04:43 You tell me how HSP, Henoch-Schonlein, is then affecting the kidney.

04:48 Could you get IgA deposition in the mesangium with HSP? Of course, you can.

04:53 Could all of these result in RPGN? That’s the point, isn’t it? Let me go into type three.

05:00 Type three that may result in RPGN, these will be Pauci-immune.

05:05 What’s Pauci mean? Pauci means little, okay, pauci means little.

05:09 So you have little immune involvement, but you are ANCA positive and when the time is right, we’ll talk about anti-neutrophil cytoplasmic antibodies being positive.

05:19 Now, the one that you all - well, you must know both of these but the one that you all know so well is granulomatosis with polyangiitis.

05:26 It was formally known as - good, Wegener.

05:30 What else do you wanna know as far as current day practice is that you know this being c-ANCA positive, don’t you? What’s the third letter of the alphabet? Ah, A, B, C, oh, wow, that’s letter C.

05:42 There it is.

05:43 So therefore, antiproteinase three, ANCA positive.

05:49 That’s a lot of words that you need to know and yes, you do need to know.

05:53 Microscopic polyangiitis, p-ANCA positive.