W3 Case Studies - Lead Poisoning & NTDs Flashcards
The three main sources of lead exposure in the U.S. are environmental, occupational, and miscellaneous. Name 1-2 sources of lead from each category.
Environmental: Paint, dust, soil, water, air, and food, with the largest contributor being leaded fuel.
Occupational: Lead containing materials at work esp. for miners, refiners, smelters, and construction. Some artists, shooting range instructors, gun-smiths, police officers (possibly)
Misc: Food and beverages, veggies, rice, milk, and fish in some areas. Moonshine (from lead-containing automobile radiators used in the the distillation process), medications (Ayurvedic meds), herbs, cosmetics, kids plastic jewelry (if chewed on).
The primary risk for pediatric lead exposure/toxicity is:
a. chipped lead paint
b. dust
c. contaminated soil
d. all of the above
d. all of the above
Deficiency in what 3 minerals can increase lead absorption?
a. iron, calcium, and zinc
b. copper, zinc, and calcium
c. copper, calcium, and zinc
d. manganese, iron, and zinc
a. iron, calcium, and zinc
Deficiency in these 3 can enhance absorption of lead in the GI tract. Calcium is specifically important. Once absorbed children store 70% lead burden in bone (adults store 90% in bone) - lead lines.
Lead impacts the kidney, leading to impaired renal biogenesis of ___________.
a. vitamin c
b. vitamin e
c. vitamin d
d. calcium
c. vitamin d
* As blood level of lead increases, serum vitamin d decreases
Treatment of vitamin D deficiency due to lead exposure should include removal of ________, and addition of ________ for 8-12 weeks.
lead exposure, vitamin d
*high strength calciferol (ergocalciferol or colecalciferol)
Is folate or folic acid more bioavailable?
Folic acid. Folic acid is synthetic, and is twice as bioavailable as folate. Folic acid is used in vitamin supplements and food fortification.
The neural tube is formed ______ days post-conception.
a. 18-30
b. 27-40
c. 100-110
a. 18-30. Therefore this may occur before a woman knows she is pregnant.
* Neural tube defects occur when the brain and spinal cord fail to close properly during the first 4 weeks of gestation. The neural tube forms the spine and brain thus defects can lead to anencephaly (absense of formation of most of the brain), spina bifida (defects in spinal closure), and open NTD’s including meningoceles, and myoceles.
Neural Tube Defects can occur for 2 reasons, which are __________ and ________.
- An increased folate demand in pregnancy not met through dietary intake,
and - A genetic defect in the production of enzymes involved in folate metabolism (including MTHFR andglutamate formiminotransferase deficiency).
Folic acid supplementation for pregnant women is recommended at _____mcg per day.
400.
*To be taken prior to conception and at least through the first trimester for the prevention of NTD’s.
True or false. Neural Tube Defect risk increases if a family member has a history of NTD’s in offspring?
True.
*In addition, pre-gestational insulin dependent diabetes and maternal pre-pregnancy obesity are environmental risk factors for NTD’s.
True or false. The term folate includes all compounds that have the vitamin properties of folic acid - including folic acid and naturally occurring compounds in food.
True.
Humans cannot synthesize folate from other sources and are therefore entirely dependent on dietary sources and/or supplements to meet requirements.
Folate functions as a methyl donor for the enzyme _____.
a. Trypsin
b. Lipase
c. MTHFR
d. Y1RC
c. MTHFR
* MTHFR is involved in the conversion of homocysteine to methionine. Folate deficiency (as well as B6 and B12) can lead to reduced breakdown of homocysteine. Increase homocysteine on blood work can signify vitamin deficiency (as well as heart disease or MTHFR gene mutation).
Food sources high in folate include:
a. Dark green leafy vegetables
b. Dried beans
c. Citrus fruits,
d. Wheat germ
f. Fortified cereals.
e. all of the above
e. all of the above
