Heavy Metal Flashcards
lead distribution
about 99% of lead in the bloodstream binds
to hemoglobin in erythrocytes; only around 1% is available to
the tissues; initially, lead is distributed to soft tissues (tubular
epithelium of the kidney and liver), but in time the lead is
redistributed and deposited mostly in bone but also in teeth
and hair
lead symptoms
a. GI: GI effects are an early warning sign of lead exposure;
anorexia, muscle discomfort, malaise, and headache;
constipation; a persistent metallic taste; lead colic (severe
abdominal pain)
b. neuromuscular: lead palsy or neuromuscular syndrome is
rare in the U.S.; muscle weakness (wrist-drop and foot-drop)
and fatigue occur long before paralysis
c. CNS: lead encephalopathy; is the most serious manifestation
of lead poisoning and more common in children; early signs
are clumsiness, vertigo, ataxia, falling, headache, insomnia,
restlessness, and irritability; later, delirium, tonic-clonic
convulsions, and coma follow; may be a progressive mental
deterioration in children
lead hematological
blood lead concentration of 80 g/dl
causes basophilic stippling (aggregated RNA) but is not
pathognomonic of lead poisoning; hypochromic microcytic
anemia is more common and reflects a decreased life span of
the erythrocytes and an inhibition of heme synthesis
e. renal: less dramatic than the CNS or GI effects
Lead lines: long bones on X-ray
lead- what accumulates in blood
delta-aminolevulinate (delta-ALA)- second step in heme synthesis is blocked by lead
protoporph accumulates in blood
lead chelators
1) Dimercaprol, 2) Succimer
(kids) , 3) EDTA and 4) penicllamine
mercury
dental amalgams & fish (methylmercury)
organic mercury
organic mercurials are more completely absorbed (90%)
from the GI tract than inorganic mercury salts; the primary
concentration is in erythrocytes and hair; t1/2 is 45-105 days
organic can cross BBB & placents
mercury is similar to …
methionine- can go thro aa transporters in the body
mercury symptoms
neurological
mercury treatment
polythiol resin
target for arsenic
sulfhydryol groups- will be found in high levels in hair and nails
arsenic half life
short compared to other metals bc it is metabolized by glutathione
chronic arsenic poisoning
a. early signs are muscle weakness and aching, skin
pigmentation (eyelids, neck, nipples and axillae)
b. less prominent GI effects; garlic odor of the breath and
perspiration
arsenic treatment
dimercaprol
cadmium half life
the half life is 10-30 years
chronic cadmium poisoning
kidney: cadmium combines with glutathione and with
metallothionine (brings it to the kidney); effects are mainly on the proximal tubule
cells
cancer: tumors of the lung, prostate, kidney and stomach
have been reported from workers exposed occupationally
to cadmium
iron poisoning symptoms
only one im worried about acute poisoning
a. occur within 30 min.
b. abdominal pain, diarrhea, brown and bloody vomitus;
pallor or cyanosis, drowsiness, hyperventilation,
cardiovascular collapse
c. death within 6 hrs or 12-24 hrs
iron treatment
deferoxamine
penicillamine
for copper poisoning- wilsons disease
trientine is alternatiev
what will flush iron pills
sorbitol
acetaminophen
acetylcysteine
anticholinesterases: organophosphates, carbamates
atropine
TCAs, quinidine
bicarb, sodium
fluoride, CCBs
calcium
theophylline, caffeine, metaproterenol
esmolol
benzos
flumazenil
methanol, ethylene glycol
alcohol
fomepizole- long acting
B- blockers
glucagon
opioids
naloxone
carbon monoxide
oxygen
antimuscarinic blockers
phyostigmine
organophosphates cholinesterase inhibitors
Pralidoxime (2-PAM)
