Newborn Screening for Metabolic and Sickle Cell Disorders Program

Testing: Lab Test

Sample Acceptability/Unsatisfactory Specimens

When testing a sample, the Laboratory makes four 1/8" punches from each "circle". Therefore, it is necessary that blood fills up the entire circle and soaks through the filter paper but does not alter the homogeneity of the filter paper surface. Prior to testing, all specimens are inspected for acceptability. Those not acceptable are reported as "UNSATISFACTORY - PLEASE RESUBMIT." When a specimen is declared "unsatisfactory", the hospital and clinician listed on the screening card are promptly notified. Submitting invalid specimens lead to the inconvenience of retesting and delays in screening, placing the newborn at risk for delayed diagnosis of a screened condition. THE INFANT MUST BE RE-SCREENED AS SOON AS POSSIBLE. It is the responsibility of the birth hospital and the listed clinician to retrieve the newborn for a repeat collection.

Currently, specimens that are declared "unsatisfactory" are tested if there is blood on the screening card. If an abnormal result is found, in the interest of the child, it is reported to the appropriate follow-up program but no other results are reported.

Categories of Unsatisfactory Specimens

• QNS – quantity of blood not sufficient for testing
• Unevenly Saturated –  blood has not completely filled the circle and/or soaked through the filter paper from front to back
• Oversaturated –  excessive application of blood; repeated layering of blood; applying blood to both sides of the filter paper
• Roughed Up –  excessive handling of the specimen card; drying the specimen with heat
• Capillary Application –  uneven application of blood from a capillary tube; tearing the filter paper with the capillary tube
• Crumpled –  excessive blood application that results in clumps/clots/retraction of the filter paper (Appears as though filter paper was put in water and then dried)
• Contaminated – excessive squeezing of the puncture site produces serous fluid; filter paper in contact with: alcohol/antiseptic solution, hand lotion or powder, food or water
• Obsolete form –  out of date filter paper form. (Check expiration date printed on green top sheet of specimen card)
• Delayed – specimen received by the laboratory 7 days after the date of collection
• No Blood – no blood on the filter paper
• Insufficient Information – failure to complete form
• Invalid Data – data on form cannot be true (e.g., date of collection prior to date of birth)
• Illegible Data – data entry staff cannot read submitter’s writing
• Blood reattached to form – filter paper with blood is stapled or reattached to the form. Does the blood specimen belong to this baby? (If you are certain that you have reattached the blood spot to the correct baby, attach a letter of verification and send to the laboratory with the specimen.)

Specimen Analysis

All specimens are tested by the primary screening method. Abnormal results are then confirmed in duplicate and, if necessary, a second confirmation test is done. Screening results are usually available 2-3 working days after the specimen is received by the newborn screening lab. Results for specimens labeled as a "Requested repeat" are usually available in 1-2 working days.

Reporting Results

A written report of all newborn screening results is mailed to the hospital of birth and the clinician listed on the screening card, if this information is included.

Depending on the disorder, abnormal results may be reported as:

• "Above normal limits" with a value given
• "Below normal limits" with a value given
• "Inconclusive"
• "Positive"

For abnormal hemoglobin results, the hemoglobin type is given with a brief explanation. All abnormal results are reported to the appropriate Follow-up Program.

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