Talk:Pernicious anemia

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I wasn't sure how to ask questions on this page so here goes! I have recently been seeing a nuerologist for possible MS diagnosis When performig blood tests he found that my intrinsic factors level was abnormal but b-12 levels were fine then he sayas I want you to get a b-12 shot every month. I said well I have to look into this he said nothing about PA I found this out for myself what do you think? —Preceding unsigned comment added by 74.47.168.202 (talk) 01:52, 6 March 2008 (UTC)

I think you need to ask your doctor, instead of random strangers on the internet. Good luck to you, WhatamIdoing (talk) 03:12, 15 March 2008 (UTC)

The

The page currently states Pernicious anemia is a caused by autoimmunity.

I suggest this is not true. Pernicious anemia is caused by B12 deficiency, yes, but not necessarily because the immune system has attacked parietal cells or has produced anti-bodies to intrinsic factor.

Mosby's Understanding Pathophysiology says:

"The underlying alteration in pernicious anemia os the absence of intrinsic factor (IF), an enzyme required for gastric absorption of dietary vitamin B12 ... Deficiency of IF may be congential or may be the result of adult-onset gastric mucosal atrophy in which the parietal cells are destroyed ... may be caused by type A chronic gastritis, an autoimmune disorder that causes destruction of parietal zymogenic cells ... In addition, pernicious anemia may be caused by heavy alcohol ingestion, hot tea, and cigarrette smoking. Pernicious anemia is also associated with other autoimmune conditions, particularly those that affect the endocrine system"

• The best model may be twofold 1)genetic susceptibility triggered by 2) an environmental disruptor. For example 1)a person with a family history of autoimmune disease such a mother with Graves disease, a father with rheumatoid arthritis and of Northern European ancestry that then 2) heavily smokes, has a heavy ethanol intake, drinks hot tea and/or coffee.Godspeed John Glenn! Will 04:44, 21 November 2006 (UTC)

I suggest that you not make silly statements that will hang around to embarrass you. Read up on the differences between Pernicious and other MEgaloblastic anemias.!65.93.33.220 (talk) 00:34, 2 January 2013 (UTC)

Thanks for thinking of him, but whatever path Will314159 was going to take after this claim was decided 6 years ago. - SummerPhD (talk) 01:49, 2 January 2013 (UTC)

Question

This is a semi-technical, semi-personal question. I was diagnosed a year ago with "a B12 deficiency" which, combined with my history of macrocytic anemia and the prescribed treatment regimen of cyanocobalamin injections since oral supplementation failed, seems to add up to pernicious anemia even though my doctor didn't use the term. However, my injections are sub-q instead of IM. Is the article wrong or incomplete, or is my doctor wrong and I'm not getting the correct treatment? My levels have stabilized in normal range since I started treatment.

I'm also inclined to think that this condition may be something of a mystery in my case, since except for the Northern European (assuming that means Anglo-Saxon/Germanic) ancestry I have none of the classic risk factors for autoimmune diseases and none of the environtmental disruptors. Isn't medicine fun? SkepticalGal 20:39, 2 April 2007 (UTC)

1. IM vs. SC question: you can probably look at the package insert for B12 to figure it out. You can pick one up at your local pharmacy... Also, you can look that up in the PDR at your local library. Wikipedia is probably not the best place to find an answer to that question. Sorry...

2. You are not understanding what B12 deficiency is, and what P.A. is. The article was lacking in this department, but I made some changes, and you hopefully will now understand what the difference is. P.A. is specifically the autoimmune phenomenon where there are antibodies directed against parietal cells or intrinsic factor. There are a lot of other etiologies of B12 deficiency, some of which I added to the P.A. page. If this is still not clear on the page, check back here. HTH. By the way, by reading about your illness and editing Wikipedia about it, you are helping reduce medical ignorance, which is a Good Thing.--67.113.79.113 05:22, 24 April 2007 (UTC)

April edits

I added some info about PA in a nice edit. Left to add is the relationship between PA and atrophic gastritis...

Answer

I do not believe that PA is caused by autoimmunity. It is caused by the lack of gastric juices in the intrinsic factor. Gastric juice helps in the absorbtion of Vitamin B12. Therefore, if there is a lack of absorbers, then how can it apsorb the needed amount of B12? It can't. This is how Mayo Clinic, Taber's Medical Dictionary, and various other sources explain it. I agree with the below statement from Mosby's encyclopedia.

I have recently heard a case of chronic PA, in other words, JPA (juvenille Pernicious Anemia). This is supposively caused by the same thing, a lack of intrinsic factor. But...the intrinsic factor was never there, hence we suppose the something malfunctioned in the stomach before the child was born. We can only guess at this.

PA was once a fatal disease before the year 1926 (I believe that is the correct year), when doctors gathered together and ran tests and polls on patients. They concluded that continuous B12 injections help the patient's recovery. Previously, PA victims ate 1/2 a pound of raw liver every day for a treatment. Dr. Adison first discovered this disease as a problem and perscribed this. Dr. Newcastle (isn't that the correct name?) found that he could regurgitate his gastric juices and feed it to his patients (of course he did not tell them where he got it). This took the place of daily liver, and these people improved. But he could not keep a steady supply, so they continued to eat liver.

For furthur research, I suggest the book "Anemia In Women". It has chapters and several lists of causes, effects, and symptoms.

Would anyone like me to post all the symptoms on the page? I have done various reports and essays on this disease for school (a lot of research). OnFire4Jesus (talk) 7:30, 1 January 2008

OnFire4Jesus, In reference to your question about posting all the symptoms, please do, along with references of course. Might I also suggest we break them down into the various systems they affect. I too have done a great deal of research and find the list misleading due to its organization and lack of completeness. Let me know if I can be of help too as this is something I was going to volunteer for before seeing your kind offer! My shrink has printed me out some recent articles that may be of use in this process.

I'm sure that your help would be welcome on this article, but you might benefit from doing a little further research first. For example, the Mayo Clinic webpage, which says (three paragraphs from the bottom of the linked page): "Lack of intrinsic factor may be due to an autoimmune reaction, in which your immune system mistakenly attacks the stomach cells that produce intrinsic factor,"[1] which is different from what you asserted above.

What this article needs most is someone to find a good, reputable, reliable source (or several) to support basically every paragraph in the article. Even just finding a website like the Mayo Clinic pages and putting the link in square brackets (like I just did) would be remarkably helpful. This free tool produces the fancier style if you prefer that (be sure to click the box to add <ref> tags, and switch from PubMed id number to regular URL for a normal webpage). WhatamIdoing (talk) 00:19, 28 January 2008 (UTC)

While I agree that an overhaul would be optimal, getting some info out there right now, is still better isn't it, then waiting on an unknown amount of time before the major overhaul? PA is rare and therefore I've found that even medical professionals have to look up the specifics, and get frustrated that information is not always up to date.

January 1 Edits

I added some to the history. I hope to add some to the causes and maybe list the symptoms in the near future... —Preceding unsigned comment added by OnFire4Jesus (talk • contribs) 01:50, 2 January 2008

I have added the commonest symptoms experienced by members of the Pernicious Anaemia Society. Following the society's use of Focus Groups to fully explore the symptoms this list of symptoms emerged. Martyn Hooper (talk) 07:34, 5 January 2009 (UTC)

I hope that you haven't just copied and pasted information off their website? That would be a serious copyright violation. WhatamIdoing (talk) 00:18, 22 January 2009 (UTC)

The "Common Physical Symptoms" section appears to be a copyvio of pernicious-anaemia-society.org The clear indication is the text "None of the above words..." which doesn't work on the wikipedia page. The writing style here is arguably POV and/or original research, or at a minimum lacking references. It should be noted, though that the "History" section of the PA society lists Martyn Hooper as the founder, so the edit is likely not in bad faith. I have added a copypaste tag to this section to flag it as a problem. Jerfgoke (talk) 19:12, 26 February 2009 (UTC)

I also think that the writing style is more "patient support" than plain "encyclopedia". Would you like to take a stab at rewriting it? WhatamIdoing (talk) 19:36, 2 March 2009 (UTC)

I went back to the pre-possible-violation state and got the (unfortunately unsourced) list, which I've copyedited into something less like a laundry list and more like a statement of common symptoms. I'd be happy to see someone else improve on it. WhatamIdoing (talk) 17:28, 10 March 2009 (UTC)

symptoms multiples

removed the double mention of fatigue, and removed the description "yellow skin" which was allready followed by the correct description, 'jaundice' —Preceding unsigned comment added by Spicypeanut (talk • contribs) 16:34, 21 January 2008 (UTC)

B is for Barely

This article desperately needs appropriate references. It shouldn't be hard to find good, solid references here. WhatamIdoing (talk) 00:04, 28 January 2008 (UTC)

Actually its harder than you think. I am recently diagnosed and have had several MDs give me conflicting information based on the resources they had. I am resourceful and dedicated to getting to the bottom of this, mainly because its affecting my own health. Still, I feel a need to educate the public about it. I have sent feelers out to some experts in the field, and I am building a small but nice stack of recent publications about PA. Though I am not a licensed medical professional, I hope that when I have organized my information and sources to be displayed, it will be suitable to the wikipolice. Unfortunately, the expert I visited last said that the worst symptom of PA is often memory loss, which I struggle with and makes it harder to speed up this process. I am making it a priority though to get my information online. PA is only found in .02% of the population, and the majority of those patients are over 60. I was diagnosed at 30, which is a less that .01% chance. I have "inspiration" to get correct up-to-date information online.~~Nfrost

Thanks, Arcadian. You have worked wonders. WhatamIdoing (talk) 05:19, 28 January 2008 (UTC)

Happy to help. --Arcadian (talk) 17:33, 28 January 2008 (UTC)

Keeping It Legit

Hey everybody. I am going to add a new chapter (is that what it's called?) on JPA (juvenille PA). I have been researching this also, as a high school student (young, but sharp) preparing to study hematology. Let's try to keep everything legit here, because it is getting out of hand with improper names. If someone needs to know the meaning of a medical word that we use here, they can look it up. Arcadian, I know it is so hard. Thankfully, today there are treatments that can help keep down the symptoms and effects. I recently studied a case from 1885 that had JPA from the day she was born until it killed her at 59 (Betsie ten Boom). OnFire4Jesus (talk) 9:03 p.m, 14 March 2008 (EST) —Preceding unsigned comment added by 75.110.157.136 (talk)

Careful. Even if we define juvenile pernicious anemia as that produced by lack of intrinsic factor in children (leaving out the other forms of B12 deficiency in children, which are far more common) there are still half a dozen mechanisms for children to be deficient in IF. So if you do a bit on this, you have to describe them all. This will get you started: [2]. And as for Ms. ten Boom, who knows what she had, unless thoroughly worked up. If she merely had anemia responsive to B12 since childhood, odds are it was a megaloblastic anemia from B12 deficiency which was NOT juvenile PA. SBHarris 01:54, 15 March 2008 (UTC)

Depending on the scope, and how different JPA really is from PA, then it might be better to create a separate article for it. It can certainly start as a section here, however. WhatamIdoing (talk) 03:12, 15 March 2008 (UTC)

MEDMOS

As some significant work is being planned, I just wanted to invite current editors to look at WP:MEDMOS for information about the current recommended sections of a disease-related article. For example, signs and symptoms are normally lumped together, presumably because average readers don't care what the technical difference is. WhatamIdoing (talk) 03:12, 15 March 2008 (UTC)

I don't see anything in WP:MEDMOS about the desirablity to "lump" signs and symptoms. Where does it say to do that? It's not a good idea anyway. If the reader doesn't know the difference between a symptom (what the patient complains of) and what the doctor sees or tests for, then they should learn. SBHarris 22:32, 25 March 2009 (UTC)

WP:MEDMOS#Diseases.2Fdisorders.2Fsyndromes: The recommended section contains both. I believe that the recommendation is based in part on the desirability of simplicity, but also because of the overlap between the categories: If I phone the physician to complain that my skin is yellow, how would you classify that? Do "symptoms", strictly defined, truly exist in the neonate? What about in a severely disabled person, e.g., due to advanced dementia? WhatamIdoing (talk) 03:22, 26 March 2009 (UTC)

By the classical definition, symptoms indeed don't exist in the person who cannot report their own problem. Thus indeed, animals, neonates, and severely demented or comatose people can have no classical symptoms. A mother calling to tell the doctor of the child's runny nose is reporting a sign. If you call the doc up and tell him or her your skin is yellow, or that it is green, orange, red, or purple, that's a symptom until your spouse gets on the phone and confirms it. At that point it becomes an (objective) sign, even if the doc hasn't seen it, yet. The point is confirmation by somebody other than the person suffering the pathological change. It might not seem epistemologically "fair" to differentiate self-report of illness from "other person report", but it's quite useful, inasmuch as a person's report of their own pathology is quantitatively and qualitatively often quite different than that of anybody else (whether family or doctor). Your report of yellow skin might be due to digitalis or conjunctival icterus, and might not be confirmed by somebody else looking at your skin. So although there is overlap, to be sure, the terminology remains useful. SBHarris 03:49, 26 March 2009 (UTC)

In general, I agree that the distinction can have value. But I think that combining them will usually produce a better encyclopedia article, especially in a disease like this one: rapid heartbeat, pallor, shortness of breath, diarrhea, jaundice, and glossitis could all be both objectively observed "signs" and patient-reported "symptoms". WhatamIdoing (talk) 04:26, 26 March 2009 (UTC)

Understandable?

Do you current editors think this article is understandable? I stated in a previous entry that readers can look up the words they do not know, but is that fair enough? I'm just trying to keep this as legit, helpful, and understandable as possible for everyone. Thanks! OnFire4Jesus (talk) 03:17, 23 March 2008 (EST)

Contradiction

I'm confused by this lone sentence in the intro: "It [pernicious anemia] is the most common cause of adult vitamin B12 deficiency.[3]" Isn't Vitamin B12 deficiency the cause of the anemia and not vice versa? The reference supports this statement ("Pernicious anemia is the most common cause of vitamin B12 deficiency in adults."),[3] but it seems contradictory to the rest of the article, which claims that Vitamin B12 deficiency is the cause of the anemia. (EhJJ)^TALK 22:09, 30 March 2008 (UTC)

As I understand it, this confusion is caused by discrepancy between what PA used to mean (as in 1800's, early 20th c) and what it means now. Back then, the condition was only detected once you were anemic. So PA referred to that type of anemia (the effects in the blood.) The more modern definition, I've gathered, is that PA refers to the lack of intrinsic factor, as explained here, whether or not you are or ever were anemic. So if you say "I have PA", it means you lack IF, not necessarily that you're anemic or even that your serum B-12 is low at the present moment. So today it's used to describe one cause of low B-12 (which can also be caused by lack of B-12 in the diet, and can still lead to anemia in that case, but then wouldn't be called PA.) I'm no expert and don't have a reference handy, but I have this condition and have done a bunch of research and talking to people about it. There is a lot of confusion on this out there, and it would be great if this article could clear it up. --Bhamster (talk) 01:29, 25 April 2008 (UTC)

NEUROLOGICAL manifestations:

Neurological manifestations of B12 deficiency include:

Dementia,

Posterlateral sclerosis of the spinal cord,

peripheral neuropathy,

anosmia, and

optic nerve disease.

Pernicious anemia most usually presents via neurological symptoms in societies where food is fortified with folic acid (because folate-fortified foods obscure the better known megaloblastic anemia seen in red blood cells when inadequate B12 is accompanied by inadequate folate.

Symptoms

Some of the neurological symptoms of this disease are not due to anemia as the cut down version of the article suggest. In particular, "mild cognitive deficits" is an insufficient explanation of the neurological manifestations of the disease which can present themselves even with a healthy RBC. Brain fog may be a little too colloquial a term, but there are significant working memory deficits, coordination problems, proprioceptive deficits, and occasionally even major depressive episodes, which medicine has come to recognize as warning signs of the illness. The current page needs better references, and it will take some significant research, but to leave the article stunted as recent edits have would be irresponsible. —Preceding unsigned comment added by 66.30.179.80 (talk) 18:49, 12 March 2009 (UTC)

Thank you for your suggestion. When you believe an article needs improvement, please feel free to make those changes. Wikipedia is a wiki, so anyone can edit almost any article by simply following the edit this page link at the top. The Wikipedia community encourages you to be bold in updating pages. Don't worry too much about making honest mistakes — they're likely to be found and corrected quickly. If you're not sure how editing works, check out how to edit a page, or use the sandbox to try out your editing skills. New contributors are always welcome. You don't even need to log in (although there are many reasons why you might want to).

You might be interested in reading about Wikipedia's standards for reliable sources in articles like this one. WhatamIdoing (talk) 23:54, 12 March 2009 (UTC)

Outside Links

I suggest that the outside link "The Pernicious Anaemia Society, a UK-based charitable organisation" be removed. You can't get any information there without "joining" -- or even contact them to tell them that their site is so slow you'll deja vu back to 1992, without joining. For instance if you click symptoms, 5 minutes later you'll get a page that says something like "you may be tired -- join for more information". If it is truly a "charitable organization" it acts like something else.71.146.16.237 (talk) 18:24, 28 January 2010 (UTC)

Causes section

In the causes section, there are currently the following two paragraphs -

"Forms of B12 deficiency other than pernicious anemia must be considered in the differential diagnosis of megaloblastic anemia. For example, a B12-deficient state which causes megaloblastic anemia and which may be mistaken for classical PA may be caused by infection with the tapeworm Diphyllobothrium latum, possibly due to the parasite's competition for B12.[9]

A similar disorder involving impaired B12 absorption can also occur following gastric removal (gastrectomy) or gastric bypass surgery, especially the Roux-en-Y bypass. In this procedure, the stomach is separated into two sections, one a very small pouch for holding small amounts of food, and the other (the remainder of the stomach), which becomes nonfunctional. Therefore, the mucosal cells are no longer available; nor is the required intrinsic factor. This results in inadequate GI absorption of B12, and may result in a syndrome indistinguishable from PA. Gastric bypass or gastrectomy patients must take B12 as in treatment of PA: either oral megadoses, or by injection."

Interesting, but tangential. This is an article about pernicious anemia and not megaloblastic anemia or b12 deficiency more generally. Any objections to removing these paragraphs?

Cheers- Wawot1 (talk) 15:56, 1 June 2012 (UTC)

Referencing

I have just read this page and realised that it is very poorly referenced. I have just seen Whatamidoing's comment on it from 2008 and I just wanted to reiterate that there are still whole sections of unreferenced writing, as well as little bits inbetween referenced text. I'm going to try to sort bits over the next few weeks. I've put in the citation needed template on large parts of unreferenced text. Simon Caulton (talk) 08:28, 21 December 2012 (UTC)

The statement under the Red Blood Cells is NOT correct.

The statement under the Red Blood Cells picture is NOT correct. "In pernicious anemia, the body does not make enough red blood cells." SHOULD read: "In pernicious anemia, the body does not make enough or any intrinsic factor." My source is ME. I have the condition and nearly died from it before it was diagnosed. Uninformed people just hear the word "anemia" and ASSUME "not enough red blood cells OR enough IRON." CaptainWoodstock (talk) 04:51, 4 April 2014 (UTC)

I think you are correct. Anemia is defined in terms of reduced hemoglobin. In pernicious anemia: Autoimmune destruction of gastric parietal cells -> reduced intrinsic factor -> reduced absorption of vit B12 -> macrocytic anemia. Removed the caption as this is the only place I could see this. Lesion 00:19, 10 April 2014 (UTC)

It is true that in pernicious anemia there is a problem with intrinsic factor and subsequent reduction of B12 absorption. However, I would argue that the caption is not incorrect because the affect is decreased production of RBCs (B12 is a necessary building block for red cells). I do think that it may be misleading, but not incorrect.

Wawot1 (talk) 22:51, 14 April 2014 (UTC)

OK, misleading not incorrect. But isn't the intrinsic factor/B12 thing what differentiates pernicious anemia from other types of anemia? If you wanted to reduce the description of the disease down to one caption, it should probably mention intrinsic factor/B12? Lesion 09:08, 15 April 2014 (UTC)

Agreed. Wawot1 (talk) 20:09, 15 April 2014 (UTC)

Epidemiology - Estimations of prevalence

Hello. The section Epidemiology says (with reference) that: « PA is estimated to affect 0.1% of the general population and 1.9% of those over 60 ».

Well, the problem is, as about 22% of people are over 60, if 1.9% of those people have PA, this disease must affect at least 0.4% of the general population.

Grasyop ^✉ 10:56, 1 March 2015 (UTC)

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Definition of Pernicious Anemia

As far as I can tell the only part of the introduction to this article that actually defines pernicious anemia is at the end of the second paragraph where it is done as an aside ("While the term pernicious anemia is sometimes also incorrectly used to indicate megaloblastic anemia due to any cause of B12 deficiency, its proper usage refers to that caused by atrophic gastritis, parietal cell loss, and lack of intrinsic factor only.").

The introduction starts out "Pernicious anaemia (--) is one of many types of the larger family of megaloblastic anemias. One way pernicious anemia can develop is by loss of gastric parietal cells..." We are told one way it develops but we don't actually get a definition of what the disease is. I think this should be right up front but I am not informed enough on this subject to make an edit. — Preceding unsigned comment added by Coyne025 (talk • contribs) 20:39, 5 March 2016 (UTC)

To add to the definition. There are multiple reasons for B12 deficiency (lack of intake (veganism), malabsorption (sprue), lack of intrinsic factor (IF)). Technically, lack of intrinsic factor, due to anti-IF antibodies or IF malfuction, is defined as pernicious anemia. However, colloquially any B12 deficiency can be called "pernicious". — Preceding unsigned comment added by Cleverwater (talk • contribs) 21:27, 12 March 2016 (UTC)

Edits of this date

I have called for an expert to address the foregoing concern (definition) and to address a comparable need to describe actual standards of care in the Diagnosis section. Ideally, one would begin the diagnosis section with brief reiteration of most common presenting symptoms (that bring patient to see the clinician), moving from there to what, e.g., physicians in the U.S., the U.K. etc, would actually do to arrive at the diagnosis of PA. Other possible or rarely used diagnostic procedures, and the historic tests, would then close the section. This is my view, absent specific expertise in hematology. Cheers, Le Prof 50.179.252.14 (talk) 03:09, 11 March 2016 (UTC)

Anemia without anemia

This sentence is very confusing:

Many of the signs and symptoms are due to anemia itself, when anemia is present.

The topic of the article is Pernicious Anemia. If anemia itself isn't always a symptom of this misnamed disease, that fact should made clear before making a statement like that quoted above. In fact, I think it should be mentioned in the first paragraph and then explained in a succeeding section. Only then can you refer to it without creating confusion. Remember to revise the quoted sentence so it refers to what's already been stated about anemia-less anemia. KC 20:41, 31 March 2016 (UTC) KC 20:41, 31 March 2016 (UTC)

Comment

This page seems to incorrectly equate B12 deficiency-related anaemias (a larger class) with pernicious anaemia (autoimmune mediated IF deficiency). See [4] for more. --Tom (LT) (talk) 05:31, 17 November 2016 (UTC)

Some use the term more loosely than to just mean IF related. For example "Pernicious anemia (per-NISH-us uh-NEE-me-uh) is a condition in which the body can't make enough healthy red blood cells because it doesn't have enough vitamin B12."[5] Doc James (talk · contribs · email) 07:10, 17 November 2016 (UTC)

@Doc James as stated in the second paragraph of the very source you state "People who have pernicious anemia can't absorb enough vitamin B12 from food. This is because they lack intrinsic (in-TRIN-sik) factor". I am guessing this is divided to make it easier to understand when reading. Pernicious anaemia refers to IF deficiency-related anaemia

Note that in ICD-10 B-12 related anaemias are a class of anaemias (class D51). Pernicious anaemia is in part (51.0) - "Anaemia due to intrinsic factor deficiency". So we are not supported by sources used in the article here. We should in fact have an article B12 deficiency-related anaemias. --Tom (LT) (talk) 07:40, 17 November 2016 (UTC)

It than goes on to say "Technically, the term "pernicious anemia" refers to vitamin B12 deficiency due to a lack of intrinsic factor. Often though, vitamin B12 deficiency due to other causes also is called pernicious anemia." Doc James (talk · contribs · email) 07:44, 17 November 2016 (UTC)