High Blood Lead Level - Capillary Test

[jesusisking1]

At our 12 month pediatrician’s appointment our baby had a heel-prick capillary blood draw test to check for lead and tested 5.5 μg/dL (3.5 μg/dL is threshold for follow-up). We were naturally really worried; our house was recently renovated but built in 1970 and I immediately went about doing research, grabbing lead test swabs to check any exposed/chipped paint, and generally quietly panicking.

We took him in for a venous blood draw the next day (nurse was a pro and baby handled it like a champ) and just got the results back. Turns out his blood lead level (BLL) was well below 3.5 μg/dL and in line with average. Huge sigh of relief.

My hypothesis- despite the nurse at the pediatrician’s office using an alcohol swab on the baby’s heel prior to the capillary test, the test picked up dust and other contaminants on the baby’s heel (he had been walking barefoot in our house earlier that day) that resulted in an inaccurately high capillary test BLL result.

Just wanted to share this for any parents who get a concerning capillary blood lead test. It certainly needs prompt follow-up, but don’t panic or get too concerned until you have a venous blood draw that can accurately assess BLL. Capillary blood lead tests (heel prick or finger prick) are helpful for screening to determine whether more testing is needed, but far from dispositive.

 

[cookiesforthree]

@jesusisking1 Capillary tests are not as reliable as venous tests. They are offered to see if a more invasive test is necessary. You’re right that the capillary test could pick up lead from the skin on baby’s heel.

However, if there is lead dust on baby’s foot, you’re not out of the woods. You’ll want to repeat testing at age 2, if not 18 months. People talk about lead paint chips but lead dust is the real culprit. If you have lead paint on doors and windows, even if it has been painted over many times (!!) when the doors/windows open and close, dust is ground off. Babies and young children will put toys, hands and feet in their mouth, all contaminated by lead dust. Horrifically, lead tastes sweet. Under age 6 or so, young children don’t have a blood brain barrier. The body doesn’t know what to do with lead so it treats it as calcium. So this poison goes right to a young child’s brain.

Source: our four year old had high lead, public health got involved, we did lead abatement, read a million DHHS pamphlets about childhood lead exposure. Happy to share links.

 

[wren84]

@jesusisking1 I mean. This means there’s heavy amounts of lead dust where your baby is walking. I wouldn’t say it was unnecessary. Now you know you need to be very vigilant about vacuuming removing shoes outside before coming in washing hands and wet mopping and wiping daily.

 

[rachelporo]

@wren84 Wet mopping daily? I can barely find the time to clean daily