Macrocytic anemia: Difference between revisions

Jump to navigation Jump to search
No edit summary
 
(19 intermediate revisions by 7 users not shown)
Line 1: Line 1:
__NOTOC__
'''For patient information click [[Megaloblastic anemia (patient information)|here]]'''
'''For patient information click [[Megaloblastic anemia (patient information)|here]]'''


Line 5: Line 6:
   Image          = Megaloblastic anemia.jpg |
   Image          = Megaloblastic anemia.jpg |
   Caption        = Megaloblastic anemia blood smear |
   Caption        = Megaloblastic anemia blood smear |
   DiseasesDB    = 29507 |
   DiseasesDB    = |
   ICD10          = {{ICD10|D|51|1|d|50}}, {{ICD10|D|52|0|d|50}}, {{ICD10|D|53|1|d|50}} |
   ICD10          = {{ICD10|D|51|1|d|50}}, {{ICD10|D|52|0|d|50}}, {{ICD10|D|53|1|d|50}} |
   ICD9          = {{ICD9|281}} |
   ICD9          = {{ICD9|281}} |
Line 14: Line 15:
}}
}}
{{Macrocytic anemia}}
{{Macrocytic anemia}}
{{CMG}}; '''Associate Editor-In-Chief:''' {{CZ}}
{{CMG}} {{shyam}}; '''Associate Editor-In-Chief:''' {{OK}}, {{ADS}}, {{CZ}}


==[[Macrocytic anemia overview|Overview]]==
==[[Macrocytic anemia overview|Overview]]==
Line 37: Line 38:


==Diagnosis==
==Diagnosis==
==[[Macrocytic anemia history and symptoms|History and Symptoms]]==
[[Macrocytic anemia diagnostic study of choice|Diagnostic Study of Choice]] | [[Macrocytic anemia history and symptoms|History and Symptoms]] | [[Macrocytic anemia physical examination|Physical Examination]] | [[Macrocytic anemia laboratory findings|Laboratory Findings]] | [[Macrocytic anemia electrocardiogram|Electrocardiogram]] | [[Macrocytic anemia x-ray|X-ray]] | [[Macrocytic anemia echocardiography and ultrasound|Echocardiography and Ultrasound]] | [[Macrocytic anemia ct|CT]] | [[Macrocytic anemia mri|MRI]] | [[Macrocytic anemia other imaging findings|Other Imaging Findings]] | [[Macrocytic anemia other diagnostic studies|Other Diagnostic Studies]]
 
==[[Macrocytic anemia physical examination|Physical Examination]]==
 
==[[Macrocytic anemia laboratory findings|Laboratory Findings]]==
 
==[[Macrocytic anemia electrocardiogram|Electrocardiogram]]==
 
==[[Macrocytic anemia chest x ray|Chest X Ray]]==
 
==[[Macrocytic anemia CT|CT]]==
 
==[[Macrocytic anemia MRI|MRI]]==
 
==[[Macrocytic anemia echocardiography or ultrasound|Echocardiography or Ultrasound]]==
 
==[[Macrocytic anemia other imaging findings|Other Imaging Findings]]==
 
==[[Macrocytic anemia other diagnostic studies|Other Diagnostic Studies]]==
 
==Treatment==
==Treatment==
[[Macrocytic anemia medical therapy|Medical Therapy]] | [[Macrocytic anemia surgery|Surgery]] | [[Macrocytic anemia primary prevention|Primary Prevention]] | [[Macrocytic anemia secondary prevention|Secondary Prevention]] | [[Macrocytic anemia cost-effectiveness of therapy|Cost-Effectiveness of Therapy]] | [[Macrocytic anemia future or investigational therapies|Future or Investigational Therapies]]


==[[Macrocytic anemia medical therapy|Medical Therapy]]==
==Case Studies==
 
:[[Macrocytic anemia case study one|Case #1]]
==[[Macrocytic anemia surgery|Surgery]]==
 
==[[Macrocytic anemia primary prevention|Primary Prevention]]==
 
==[[Macrocytic anemia secondary prevention|Secondary Prevention]]==
 
==[[Macrocytic anemia cost-effectiveness of therapy|Cost-Effectiveness of Therapy]]==


==[[Macrocytic anemia future or investigational therapies|Future or Investigational Therapies]]==


==Case Studies==


==[[Macrocytic anemia case study one|Case #1]]==


===Hematological findings===
MCV is often >110.  Hct can often be as low as 15.  Elevated LDH and bilirubin are seen since dyserythopoesis leads to destruction of >90% of RBC precursors.  Hypersegmentation of PMNs is quite sensitive (>5% with 5 or more lobes or >1% with 6 lobes).  Reticulocyte, WBC and platelets are low to normal.  In one series of patients with B12 deficiency, 64% had a MCV greater than 100, and only 29% had anemia.
In general the [[blood film]] can point towards vitamin deficiency:
*Decreased [[red blood cell]] (RBC) count and [[hemoglobin]] levels
*Increased [[mean corpuscular volume]] (MCV >95 fl often >110) and [[mean corpuscular hemoglobin]] (MCH)
*The [[reticulocyte]] count is normal
*The [[platelet]] count may be reduced.
*[[Neutrophil granulocyte]]s may show multisegmented nuclei ("senile neutrophil"). This is thought to be due to decreased production and a compensatory prolonged lifespan for circulating neutrophils.
*[[Anisocytosis]] (increased variation in RBC size) and [[poikilocytosis]] (abnormally shaped RBCs).
*Macrocytes (larger than normal RBCs) are present.
*Ovalocytes (oval shaped RBCs) are present.
*[[Bone marrow]] (not normally checked in a patient suspected of megaloblastic anemia) shows megaloblastic [[hyperplasia]].
*[[Howell-Jolly body|Howell-Jolly bodies]] (chromosomal remnant) also present.


'''Blood chemistries will also show:'''
*Increased homocysteine and methylmalonic acid in B12 deficiency
*Increased homocysteine in folate defiency
<div align="left">
<gallery heights="175" widths="175">
Image:Peripheral blood in megaloblastic anemia 0001.jpg|Peripheral blood in megaloblastic anemia
Image:Howell-Jolly bodies 0001.jpg|Howell-Jolly bodies
Image:Howell-Jolly bodies and erythroblast.jpg|Howell-Jolly bodies and erythroblast
</gallery>
</div>


===Analysis===
The [[Schilling test]] was performed in the past to determine the nature of the vitamin B12 deficiency, but due to the lack of available radioactive B12, it is now largely a historical artifact.  Vitamin B{{ssub|12}} is a necessary prosthetic group to the enzyme [[methylmalonyl-coenzyme A mutase]].  B{{ssub|12}} deficiency leads to dysfunction of this enzyme and a buildup of its substrate, [[methylmalonic acid]], the elevated level of which can be detected in the urine and blood.  Since the level of methylmalonic acid is not elevated in folic acid deficiency, this test provides a one tool in differentiating the two. However, since the test for elevated methylmalonic acid is not specific enough, the gold standard for the diagnosis of B12 deficiency is a low blood level of B12. Unlike the Shilling test, which often included B12 with intrinsic factor, a low level of blood B12 gives no indication as to the etiology of the low B12, which may result from a number of mechanisms.


==Treatment==
* Folate is administered 1mg QD.  Higher doses may be required in malabsorptive syndromes.  It is empirically given to those with SCD and those on HD.
* B12 must be given as a load then maintenance.  Most advocate 1000 mcg IM Qweek x4 then 100mcg/month.
* LDH falls in 2 days.  Hypokalemia requiring replacement can occur in the acute phase as new cells are being generated rapidly.
* A reticulocytosis begins in 3-5 days and peaks in 10 days.  The HCT will rise within 10days.  If it does not, suspect another disorder.  Hypersegmented PMNs disappear in 10-14 days.
* Neurologic abnormalities may take up to 6 months to resolve if ever.  The longer the disease has been present, the worse is the prognosis for recovery.
* Persons with PA have a 2x risk of gastric CA (in some studies).  Screen for occult blood.


[[el:Μακροκυτταρική αναιμία]]
[[sq:Anemi makrocitike]]
{{WikiDoc Help Menu}}
{{WikiDoc Sources}}


==References==
{{Reflist|2}}
[[es:Anemia megaloblástica]]
[[gl:Anemia megaloblástica]]
[[he:אנמיה מגלובלסטית]]
[[it:Anemia megaloblastica]]
[[pl:Niedokrwistość megaloblastyczna]]
[[pt:Anemia megaloblástica]]
[[ru:Пернициозная анемия]]
[[sl:Megaloblastna anemija]]
[[sr:Мегалобластна анемија]]
[[tr:Megaloblastik anemi]]


{{WikiDoc Help Menu}}
{{WikiDoc Help Menu}}

Latest revision as of 16:31, 2 December 2018

For patient information click here

Macrocytic anemia
Megaloblastic anemia blood smear
ICD-10 D51.1, D52.0, D53.1
ICD-9 281
MeSH D000749

Macrocytic anemia Microchapters

Home

Patient Information

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Macrocytic anemia from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

Diagnostic Study of Choice

History and Symptoms

Physical Examination

Laboratory Findings

Electrocardiogram

X-ray

Echocardiography and Ultrasound

CT

MRI

Other Imaging Findings

Other Diagnostic Studies

Treatment

Medical Therapy

Surgery

Primary Prevention

Secondary Prevention

Cost-Effectiveness of Therapy

Future or Investigational Therapies

Case Studies

Case #1

Macrocytic anemia On the Web

Most recent articles

Most cited articles

Review articles

CME Programs

Powerpoint slides

Images

American Roentgen Ray Society Images of Macrocytic anemia

All Images
X-rays
Echo & Ultrasound
CT Images
MRI

Ongoing Trials at Clinical Trials.gov

US National Guidelines Clearinghouse

NICE Guidance

FDA on Macrocytic anemia

CDC on Macrocytic anemia

Macrocytic anemia in the news

Blogs on Macrocytic anemia

Directions to Hospitals Treating Macrocytic anemia

Risk calculators and risk factors for Macrocytic anemia

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Shyam Patel [2]; Associate Editor-In-Chief: Omer Kamal, M.D.[3], Amandeep Singh M.D.[4], Cafer Zorkun, M.D., Ph.D. [5]

Overview

Historical Perspective

Classification

Pathophysiology

Causes

Differentiating Macrocytic anemia from other Diseases

Epidemiology and Demographics

Risk Factors

Screening

Natural History, Complications and Prognosis

Diagnosis

Diagnostic Study of Choice | History and Symptoms | Physical Examination | Laboratory Findings | Electrocardiogram | X-ray | Echocardiography and Ultrasound | CT | MRI | Other Imaging Findings | Other Diagnostic Studies

Treatment

Medical Therapy | Surgery | Primary Prevention | Secondary Prevention | Cost-Effectiveness of Therapy | Future or Investigational Therapies

Case Studies

Case #1






Template:WikiDoc Sources