TMPPM 2007 >J.3 Measuring Blood Lead Levels

J.3 Measuring Blood Lead Levels

Recent or ongoing exposures to lead can be detected by a blood test. Blood lead levels are stated as micrograms of lead per deciliter of whole blood. The Centers for Disease Control and Prevention (CDC) defines a blood lead level of 10 µg/dL a "level of concern," which is also the measurement standard in Texas for an "elevated blood lead level" and requires follow-up. The blood lead "level of concern" should not be interpreted as a definitive toxicological threshold. Mounting evidence suggests adverse health effects in children with blood lead levels below 10µg/dL and no definitive threshold for adverse effects has been demonstrated.

Blood lead tests, in order of occurrence:

•Screening test-A blood lead test to determine whether the client has an elevated blood lead level.

•Diagnostic test (confirmatory)-A venous blood lead test performed within recommended guidelines on a client who has previously had an elevated blood lead level on a screening test. Unless the diagnostic test occurs within six months of the screening date, it is not a diagnostic test but rather a new screening test.

•Follow-up test-A blood lead test to monitor the status of a client with a previously elevated diagnostic test for lead.

Note: This is not related to the THSteps follow-up visit. A visit to monitor a child with elevated blood lead tests would be submitted as an acute care evaluation and management (E/M) visit.

A screening test may be drawn from a venous site or capillary. Venous drawn is strongly recommended and preferred. Providers are responsible for conducting a diagnostic test when a screening test finds lead at 10 µg/dL or greater.

Note: The capillary lead screen analysis is subject to a false-elevated result from skin lead contamination during collection. A soap and water wash of the patient's hands or feet and the collector's hands (or the wearing of gloves) must be performed to minimize the chance of contamination. Alcohol cleansing alone is not sufficient.

If the initial blood lead test is 10 µg/dL or above, recalling a client for an office visit to take a venous blood sample may be billed as a THSteps follow-up visit. The specimen may be submitted, using the appropriate Department of State Health Services (DSHS) laboratory form, to the DSHS Clinical Chemistry Laboratory the same way as for all other THSteps laboratory blood specimens. An initial blood lead test collected as part of a THSteps medical check up must be submitted to the DSHS laboratory; subsequent screens for the same client may be sent to a private laboratory.

Refer to: Form Pb-109 "Form Pb-109: Physician Reference on Follow-up Testing and Case Management" for interpretation of laboratory test results and guidelines for follow-up for clients with elevated blood lead levels.

Providers may obtain more information about the medical and environmental management of lead-poisoned children from the DSHS Childhood Lead Poisoning Prevention Program (CLPPP) by visiting the website at www.dshs.state.tx.us/lead/ or by calling 1-800-588-1248.