People Screened with Faulty Lead Tests Need Rechecks
The Centers for Disease Control and Prevention (CDC) recently issued a health advisory alerting healthcare providers and public health officials of a recall of faulty blood lead tests. The U.S. Food and Drug Administration (FDA) has issued the most serious type of recall (class I) because there is significant risk that the tests can return falsely low blood lead levels.
The faulty test kits are point-of-care tests that use drops of blood collected by pricking a finger or heel (for infants). The kits were distributed for use in clinical laboratories, healthcare providers’ offices, clinics and hospitals throughout the U.S. The FDA and the test manufacturer, Magellan Diagnostics, Inc., are instructing clients to discontinue using specific LeadCare® test kits and lots that were distributed October 27, 2020 to June 15, 2021.
The recall may have wide ranging implications. The vast majority of lead screenings are performed at the point-of-care, and the LeadCare® kits are some of the most widely used kits for point-of-care testing.
Falsely low lead results can mislead some healthcare providers and their patients to think the patients have not been exposed to dangerous levels of lead when they have indeed been exposed. Inaccurate blood lead results can cause serious harm because patients with elevated levels may not get the follow-up and treatment they need.
Lead is a metal that is present in small amounts throughout our environment. It is used in many industries and hobbies, and can be found in the paint and water pipes of some older homes built prior to 1978. Lead can be highly poisonous when it is breathed in as dust, swallowed, or absorbed through the skin. When it is absorbed into our bodies, it is stored in the blood, bones, and other tissues. This stored lead can be an ongoing source of lead poisoning, and it can take years for the level of lead to decrease in the body.
Children are especially vulnerable to lead’s toxic effects because their brains and nervous systems are still developing. Children with high lead levels can experience damage to their brains and nervous systems, may grow and develop more slowly than other children their age, and may have problems with learning, behavior, speech and hearing. No level of lead in children is considered safe.
Young children tend to be at higher risk for lead exposure because they often touch objects that can be contaminated with lead dust and then put their hands, or those objects, in their mouths. Others at high risk of lead exposure include some pregnant women, and adults who work in industries that could expose them to lead.
Groups at risk for lead poisoning are routinely screened by having their lead levels measured using blood collected from a fingerstick. Levels above 5 micrograms per deciliter (mcg/dL) require confirmation by collecting blood from a vein and using an alternate, more complex, method of testing performed in a laboratory, which is considered to be more accurate. Results that read below 5 mcg/dL usually require no follow up. With this recent recall, however, individuals screened with the defective test kits with results below the threshold level require retesting, according to the CDC.
Who should be retested?
The CDC advises that healthcare providers talk about the recall and the recommendation to be retested with patients and parents or caregivers of children who were initially tested with the defective kits. Any healthcare provider unsure whether any blood lead levels they have reviewed are affected by the recall are advised to contact the director of the lab that performed the test.
Retesting is recommended for:
- Children who were tested with the recalled test kits who had results less than 5 mcg/dL
- Children who were tested with a LeadCare test kit between October 27, 2020 and July 6, 2021 (the date of the CDC health advisory), and the lot number of the test kit is unknown
- Individuals who should be given priority for retesting include:
- Children with signs and symptoms or developmental problems that may be related to lead exposure
- People at higher risk of elevated lead levels
- Women who are pregnant or breastfeeding
Retesting should be done with a sample of blood drawn from a vein and performed with a different (and more complex) testing method than the original point-of-care screening test. This lead retesting is often available through local or state health departments, which can be important resources for patients and parents seeking testing.
Any retesting results above the recommended threshold should have follow up based on the CDC’s Recommended Actions Based on Blood Lead Level.
The current recall is the second incident in recent time that Magellan Diagnostic lead tests have been found to be defective. In 2017, the FDA and the CDC warned against using LeadCare® analyzers to test blood samples drawn from veins because they might return falsely low lead levels. Blood samples that were collected by fingerstick were not part of the 2017 CDC Health Alert, but it was recommended that patients who were initially screened using venous blood samples undergo retesting.
(July 6, 2021) Recall of LeadCare® Blood Lead Tests Due to Risk of Falsely Low Results. CDC Health Alert Network. Accessed 7/28/2021. https://emergency.cdc.gov/han/2021/han00445.asp
(July 9, 2021) Magellan Diagnostics Recalls LeadCare II, LeadCare Plus, and LeadCare Ultra Blood Lead Tests Due to Risk of Falsely Low Results. FDA Medical Device Recalls. Accessed 7/28/2021. https://www.fda.gov/medical-devices/medical-device-recalls/magellan-diagnostics-recalls-leadcare-ii-leadcare-plus-and-leadcare-ultra-blood-lead-tests-due-risk
(July 27, 2021) Centers for Disease Control and Prevention. Childhood Lead Poisoning Prevention Program. Accessed 7/28/2021. https://www.cdc.gov/nceh/lead/default.htm
(November 2, 2020) Centers for Disease Control and Prevention. Recommended Actions Based on Blood Lead Level. Accessed 7/28/2021. https://www.cdc.gov/nceh/lead/advisory/acclpp/actions-blls.htm
(April 5, 2021) Centers for Disease Control and Prevention. Blood Lead Levels in Children. Accessed 7/28/2021. https://www.cdc.gov/nceh/lead/prevention/blood-lead-levels.htm
(January 7, 2020) Centers for Disease Control and Prevention. Childhood Lead Poisoning Prevention Program: Health Effects of Lead Exposure. Accessed 7/28/2021. https://www.cdc.gov/nceh/lead/prevention/health-effects.htm
(April 21, 2021) Centers for Disease Control and Prevention. Childhood Lead Poisoning Prevention Program: Populations at Higher Risk. Accessed 7/28/2021. https://www.cdc.gov/nceh/lead/prevention/populations.htm
(June 18, 2018) Lead: Information for Workers, Health Problems Caused by Lead. The National Institute for Occupational Safety and Health (NIOSH). Accessed 7/28/2021. https://www.cdc.gov/niosh/topics/lead/health.html
(June 18, 2018) Lead: Information for Workers, Jobs That May Have Lead Exposure. The National Institute for Occupational Safety and Health (NIOSH). Accessed 7/28/2021. https://www.cdc.gov/niosh/topics/lead/jobs.html
(May 17, 2017) Potential for Falsely Low Blood Lead Test Results from LeadCare® Analyzers. CDC Health Alert Network. Accessed 7/28/2021. https://emergency.cdc.gov/han/han00403.asp