Blood Transfusion and Leukocyte Depletion

Leukocyte Depletion Filter

• Speed of infusion: 15gtts = 1mL, 60gtts = 1min, 1min = 4mL, 1hr = 240mL, Rate = 240mL/hr
• 1 unit must be completed within 4hrs of blood transfusion

Polyagglutination

• Also known as Hubener-Thomsen-Fridenrich Phenomenon
• Cryptantigens (Hidden Ag9s) are covered with N-acetylneuraminic acid (NANA) or sialic acid
• When NANA is destroyed (by neuraminidase), Ag9s are exposed
• Exposed Ag9s react with tetrasaccharide of Thomas & Winzler (T receptor)

Microbially-Associated Polyagglutination

• Caused by bacteria that produce neuraminidase:
• C.perfringens
• V.cholerae
• S.pneumoniae
• E.coli
• Proteus sp.

ABO Hemolytic Disease of the Newborn (ABO HDN)

• Mother: Group O
• Child: Group A or B

Group I Discrepancies

• Weak reacting/missing Ab9s
• Occurs in:
• Newborns
• Elderly patients
• Hypogammaglobulinemia/agammaglobulinemia

Group II Discrepancies

• Weak reacting/missing Ag9s (less frequent)
• Occurs in:
• Leukemia
• Acquired B phenomenon
• Subgroups of A
• Hodgkin's disease
• BGSS (Remedy: Wash RBCs)

Group III Discrepancies

• Plasma abnormalities resulting in Rouleaux formation (Plasma factor)
• Caused by:
• ñ globulins: MM, WM, HL
• ñ fibrinogen
• Dextran and PVP
• Wharton's jelly (Remedy: Wash cord cells 6-8x)

Group IV Discrepancies

• Miscellaneous:
• Polyagglutination
• Anti-I (cold agglutinin)
• Cis > E > C > e (Least immunogenic)

Rh Blood Group System

• R or r
• D or d
• 1 or 8
• Ce
• 2 or 89
• cE
• Z or y
• CE
• G: D+C+ red cell
• Rh: 13, 14, 15, 16 (4 different parts of the D mosaic)

Weak D

• Genetic weak D: D Ag9s expressed appear complete but few in number
• D Mosaic (Partial D): if one or more parts of D Ag is missing → weakened expression of D Ag
• May produce anti-D (Ab against missing fragment)

Other

• C Trans: D ---(trans)---> C (Ex. Produce weaker neuraminidase)
• Tx: Bacterial and viral, unknown mechanism
• Tk: N-acetyl + galactosamine, Galactosamine = Group B
• Remedy: Add acetic anhydride
• VA: Vienna, Virginia, Microbial fucosidase = òfucose = òH
• Acquired Non-Microbially Associated Polyagglutination:
• Tn: (-) β-3-D-galactosyltransferase enzyme needed for the normal structure of T receptor (Tetrasaccharide of Thomas and Winzler)
• Inherited Polyagglutination:
  • Cad: ñSd a
  • HEPAS/CDA II: ñAdult i Ag = òH Ag, òSialic acid
  • Others: HbM – Hyde Park, NOR = Norfolk, Virginia

Autologous Donation

• Predeposit AD: Before anticipated transfusion
• Requirements:
• No age limit
• No strict weight requirement (òvol)