ANTIBODY TITER

Mnemonic

ABT

Synonym

Rh Titer

Includes

Determination of antibody titer by serial dilution.

Guidelines

Measures titer in antenatal maternal serum when antibody screen is positive. Useful to follow the development of antibody formation in cases of maternal-fetal blood incompatibility.

Specimen Collection Requirements

Collect

Three full 4.0 mL lavender (EDTA) top tubes

Handling

Tubes must be labeled appropriately. See Blood Bank Specimen Collection Guidelines.

Preferred Volume

Three full 4.0 mL lavender (EDTA) top tubes

Minimum Volume

Two full 4.0 mL lavender (EDTA) top tubes

Transport

Ambient or refrigerated

Rejection Criteria

Gross hemolysis, incorrect specimen container, incorrectly labeled or frozen specimen

Stability

Ambient: 24 hours; Refrigerated: 3 days; Frozen: Unacceptable

Testing Information

Note

Remaining plasma is frozen for subsequent parallel titers.

Performed

Mon - Fri 7:00 am - 3:30 pm

Method

Serial dilution, saline incubation followed by Antihuman globulin technique (AHG, Coombs')

Referral Lab

Samaritan Health Services Laboratories

Reference Values

Reference Values

An Anti-D titer of 16 is considered significant.
Critical titers for antibodies other than Anti-D have not been well defined.
A three-fold rise in titer is considered significant.

CPT Codes

86886

Blood Product

Limitations

While correlation does exist between titer and severity of erythroblastosis, titers do not always reflect the condition of an unborn child. False-negatives and false-positives occur. Abnormal results may indicate the need for amniocentesis

Last Updated: Thursday, January 5, 2017 03:41:59 AM