c5-INBORN ERRORS OF METABOLISM.docx

INBORN ERRORS OF METABOLISM =========================== In the U.S., newborns are routinely screened for various metabolic and genetic defects by analyzing a blood sample collected on a specific filter paper. Screening newborns assists in the early detection of genetic, metabolic, and infectious di...

INBORN ERRORS OF METABOLISM =========================== In the U.S., newborns are routinely screened for various metabolic and genetic defects by analyzing a blood sample collected on a specific filter paper. Screening newborns assists in the early detection of genetic, metabolic, and infectious diseases and disorders. Blood-spot testing for newborn screenings are performed before the newborn is 72 hr. old. If the specimen is obtained before the newborn is 24 hr. old, a second specimen should be obtained for screening up to 2 weeks of age. Screenings aid in the early detection, diagnosis, and treatment of the following conditions. - Cystic fibrosis - Hypothyroidism - Phenylketonuria (PKU) - Galactosemia - Other genetic disorders (biotinidase deficiency, sickle cell disease) - Infectious diseases (human immunodeficiency virus \[HIV\], toxoplasmosis) Newborn screenings are state-required blood specimens that are collected onto specific forms or cards. These forms include absorbent areas called filter paper. Fill out the forms completely in ink with all required information and check the forms for expiration dates; the substances within the absorbent areas can expire. Double-check that the guardian\'s phone number is correct and included on the form. If any of the tests performed have positive results, the parent or guardian will be notified immediately so appropriate care and treatment can begin. Newborn screenings are almost always performed as a capillary puncture on the infant's heel. To perform a heel stick on an infant, you must follow the procedures listed on the required state forms. Following is a common list of instructions used in the collection of these samples. - Properly identify the infant. - Ensure that the paperwork or card is filled out completely, including parent's/guardian's phone number. - Avoid touching the filter paper part, even with gloved hands, to prevent contamination. - Wash hands and don gloves. - Check the temperature of the infant's heel, and warm it if necessary. - Cleanse the infant's heel with an antiseptic and allow the skin to dry. - Puncture the heel, across the prints of the heel, with a semi-automated lancet device no deeper than 2 mm. - Wipe off the first drop of blood. - Allow a large blood droplet to form at the puncture site. - Touch the filter paper to the drop of blood to soak through completely in each circle. The circles must be totally saturated. This is evident by viewing the paper from both sides. *Blood is applied to only one side of the form. Avoid touching the skin with the card. Avoid blotting or attempting to color in the circle with several blood drops, this can cause serum rings and alter test results.* - Do not use capillary tubes because they often make the filter paper rough and cause overabsorption. - Air-dry the blood spots thoroughly for 3 hr. at room temperature. Keep them away from direct sunlight and heat. - Wet filter papers should not touch each other because they are sticky and will adhere to other forms. Once thoroughly dried, mail state collection forms to the appropriate state laboratories for testing. Send the cards with all other required paperwork. It is important that infants who test positive for these conditions are treated quickly. Do not postpone submitting completed collection cards. These specimens can be unusable and rejected if any of the following occur: - A circle is oversaturated. - All circles are not completely filled. - An expired form is used. - The form is not received within 14 days of collection. - The specimen is contaminated with a foreign substance. - The specimen is not allowed to dry thoroughly. - The circles have serum rings.