Quantcast Cold Antibodies - Immunohematology and Blood Banking II

Share on Google+Share on FacebookShare on LinkedInShare on TwitterShare on DiggShare on Stumble Upon
Custom Search
 
  
 
(2)  Variation in the strength of the antigen. Some antigens that do not show
dosage in terms of zygosity may vary in strength on cells from different individuals. The
antigens most notable for this are P1, Sda, Lea, Leb, and I. Sometimes diminished
antigenic strength can be related to disease, or to the length of time that the cell
suspension has been stored.
1-38. COLD ANTIBODIES
a. Background. These antibodies react best at room temperature (RT) and
below, while reactions after 37C incubation and with AGT are negative or weakly
positive. Some cold agglutinating antibodies, notably anti-I, anti-lH, and anti-H, bind
complement following the antigen-antibody interaction at low temperatures; subsequent
37C incubation may cause the antibody to elute from the cell, but the attached
complement remains, and produces a positive reaction when antiglobulin serum is
added. An antibody displaying these characteristics in the screening test or in
crossmatches should be tested at 18C and/or 4C with specially selected cells, such as
cord cells.
b. Cold Autoabsorption to Remove Cold-Reactive Autoantibody.
(1)  When a strong, cold, autoantibody is present, meaningful
antibody-screening and compatibility studies cannot be done until the autoantibody is
removed. This can be done with the patient's untreated or enzyme-treated cells.
Enzyme pretreatment results in faster antibody removal, and is more effective with very
high-titered autoantibodies. Untreated autoabsorption is usually satisfactory for
removing low-level activity.
(2)  Some alloantibody may also be removed by the Matuhasi-Ogata
phenomenon, or by transfused cells in the circulation. In recently transfused patients,
when autoabsorption might result in removing alloantibody activity, the
antibody-screening test and compatibility tests should be done at 37C, using serum
from a blood sample clotted at 37C and kept at that temperature until the serum is
removed. This permits detection of antibodies active at 37C, and by AGT, but not
cold-reactive alloantibodies.
(a) STEP 1. Obtain a blood specimen from the patient. At the bedside
draw two specimens of blood, one in a tube immediately placed in ice, the other in a
tube containing anticoagulant and incubate it at once at 37C. To do this, bring a
heated block, water bath, or vacuum jug of 37C water to the patient's bedside. The
tube may also be transported in an inside pocket.
(b) STEP 2. Allow the first (iced) specimen to clot in the refrigerator.
Separate the serum by centrifuging in ice-filled cups or a refrigerated centrifuge.
Immediately remove the serum from the clot.
MD0846
1-52



Medical News
New Regimens Boost Optimism for Pancreatic Ca (CME/CE)
SAN FRANCISCO (MedPage Today) -- Stereotactic ablative radiation allowed 40%...
medpagetoday.com
This Week: Ebola, Interns, and Low-T Tx
(MedPage Today) -- An exclusive piece on the rising costs...
medpagetoday.com
Twenty-four percent of middle-aged and older Americans meet muscle-strengthening guidelines
Past research has shown that strength training can benefit older...
scopeblog.stanford.edu
Twenty-four percent of middle-aged and older Americans meet muscle-strengthening guidelines
Past research has shown that strength training can benefit older...
scopeblog.stanford.edu
Vitamin K antagonist plus clopidogrel feasible for PCI
(HealthDay)—Vitamin K antagonists (VKA) combined with clopidogrel may be a...
medicalxpress.com
Electronic health records tied to shorter time in ER
(HealthDay)—Length of emergency room stay for trauma patients is shorter...
medicalxpress.com
Tight blood sugar control doesn't prevent strokes in diabetics
(HealthDay)—A six-year study of people with type 2 diabetes found...
medicalxpress.com
Friday Feedback: Docs Defend Fee-for-Service
(MedPage Today) -- Are American healthcare providers ready to let...
medpagetoday.com
Presence of peers ups health workers' hand hygiene
(HealthDay)—The presence of other health care workers improves hand hygiene...
medicalxpress.com
Surgical Training Can Be Fun and Games
(MedPage Today) -- Competition and prizes motivated surgical residents to...
medpagetoday.com
UN: Ebola 'Threat to Security'
(MedPage Today) -- The West Africa Ebola epidemic is a...
medpagetoday.com
Study explores docs' roles in end-of-life hospitalizations
(HealthDay)—Family physicians have several distinct roles in preventing and guiding...
medicalxpress.com
Adults over 45 not meeting US muscle strengthening guidelines, study says
(HealthDay)—Although there is mounting evidence that muscle-strength training provides key...
medicalxpress.com
Germany, France plan air lifts to help fight Ebola
Germany and France will send military transport planes to West...
medicalxpress.com
When A Hospital Closes
BELHAVEN, N.C. (MedPage Today) -- People in this one-stoplight farming...
medpagetoday.com
Researchers reveal pathway that contributes to Alzheimer's disease
Researchers at Jacksonville's campus of Mayo Clinic have discovered a...
medicalxpress.com
Research predicts possible 6,800 new Ebola cases this month
New research published today in the online journal PLoS Outbreaks...
medicalxpress.com
A better way to track emerging cell therapies using MRIs
Cellular therapeutics – using intact cells to treat and cure...
medicalxpress.com
SBRT Transforms Lives of Many With NSCLC (CME/CE)
(MedPage Today) -- A cohort of patients with inoperable non-small...
medpagetoday.com
New surgeons take time out for mental health
I spent a recent morning watching about 30 Stanford surgical...
scopeblog.stanford.edu
 


Privacy Statement - Copyright Information. - Contact Us

comments powered by Disqus

Integrated Publishing, Inc.
9438 US Hwy 19N #311 Port Richey, FL 34668

Phone For Parts Inquiries: (727) 755-3260
Google +