Radon/CO/Lead poisoning Flashcards
Radon is a byproduct of uranium that usually accumulates in which 2 areas of high exposure?
Soil & Basements
Describe how radon leads to DNA damage in lung cancer
The byproducts of radon decay are alpha-emitters which cause irritation to the respiratory epithelial cells and DNA damage.
Note if a patient presents with lung cancer before 40yrs of age & they’ve never smoked suspect RADON poisoning!!!
If a patient under 40yrs old presents with lung cancer & they’ve never smoked &/or had little/no secondhand smoke exposure what causal agent should you expect?
Radon Poisoning
Poisoning:
- Burton’s lines (lead-lines on gingivae & metaphysis of long bones)
- Encephalopathy
- Erythrocyte basophilic stippling
- Abdominal colic
- Sideroblastic anemia
- Wrist/foot drop
What’s the poisoning?
Lead poisoning
Poisoning:
Describe some of the signs of lead poisoning
- Burton’s lines (lead-lines on gingivae & metaphysis of long bones)
- Encephalopathy
- Erythrocyte basophilic stippling
- Abdominal colic
- Sideroblastic anemia
- Wrist/foot drop
Describe how exposure to high levels of lead leads to lead poisoning
Lead has a high affinity for sulfhydryl groups, disrupts heme synthesis in the bone marrow erythroblasts by inhibiting gamma
Poisoning:
Labs:
Normal PaO2
Left shift on the O2-Hb curve
CO poisoning, a non-irritating, colorless, & odorless gas that can come from motor exhaust, gas furnaces, & fires
Describe the pathophysiology about how CO causes extreme tissue hypoxia
Carbon monoxide (CO) is able to bind to hemoglobin (Hb) 200 times more strongly than oxygen, which means that it “steals” Hb and combines with it to form carboxyhemoglobin.
This disrupts aerobic metabolism & lipid peroxidation by inhibiting complex IV in the ETC (aka cytochrome C)
Because of the way carboxyhemoglobin affects the way cells use oxygen, it makes it harder for supplemental oxygen to help.
Which 2 tissues within the hypothalamus are most sensitive to the effects of CO poisoning?
Basal ganglia & Lenticular nuclei
Poisoning:
Headaches
Cherry red skin
Vomiting
Confusion
Coma (within 5 mins)
Visual disturbances
Short term memory loss
What’s the condition?
CO poisoning
Describe the neurological sequelae of CO poisoning (aka long term neuro effects)
Motor disturbances
Peripheral neuropathy
Hearing loss
Vestibular abnormalities
Dementia
Psychosis
What is considered criteria for a poor prognosis for a person suffering from CO poisoning?
They’re older than 35yrs
They had CO exposure for over 24hrs
They have acidosis or are unconscious
Cardiorespiratory arrest
Cherry red skin & mucus membranes are associated with what condition
Acute exposure to CO poisoning because CO is accumulated in the superficial capillaries
For long term survivors of CO poisoning tend to have neurophysiological sequelae
Motor disturbances
Peripheral neuropathy
hearing loss
Vestibular abnormalities
Dementia
Psychosis
Sources of lead poisoning
Lead paint chips
Corrosion of lead poisoning
Folk medicines (azarcon & greta)
Are children or adults more at risk of lead poisoning
Children absorb 45-50% lead
What is a major risk of lead poisoning in pregnant women
Lead can be distributed in the blood through RBCs which can cross the placenta to affect the fetus
What is the order or lead excretion
urine > poop >hair, nails, sweat
Describe why patients chronic lead exposure may still experience side effects years-month later on
Distribution of lead from bones (up to 30YRS) into soft tissue can increase blood levels o lead for months to years after the source of contamination is removed
Describe the pathophysiology of lead exposure on the body in heme synthesis
It inhibits Delta-aminolaevulinic acid dehydratase & ferrochetalase to ignore heme synthesis
Describe the pathophysiology of lead exposure on the body in bones
It competes with Ca to deposit in bones and mess with metaphyseal & primary bone trabeculae in the epiphysis (aka lead stores on growth plates & increase bone densities.
Describe the pathophysiology of lead exposure on the body in renal function
Lead can cause proximal tubule damage associated with intranuclear lead inclusions & protein aggregates which can lead to chronic renal damage (Interstitial & Renal failure)
Labs:
Accumulation of urine coproporphyrin indicates what type of poisoning?
It indicates lead poisoning because it interferes with Delta-aminolaevulinic acid dehydratase
- Wrist drop (radial neuropathy due to elevated coproporphyrin)
- Nausea/clumsy
- Abdominal pain
- Ringed sideroblasts (inhibited ferrochetalase)
- Stippled RBCs
- Microcytic & hypochromic anemia
- Gingival lead lines (burtons)
- Dense metaphyseal bands on long bones (burtons)
Lead poisoning
What are sources of arsenic poisoning
Soil
Water
Wood preservatives
Herbicides
Mines
Smelting ind
What are the 3 most toxic forms of arsenic?
Arsenic trioxide
Sodium arsenite
Aresenic trichloride
Describe the pathophysiology of arsenic poisoning
It interferes with mitochondrial oxidative phosphorylation because it replaces 3 phosphate groups in ATP to inhibit enzyme activity and inhibits pyruvate dehydrogenase both causing apoptosis
Describe neurological symptoms of arsenic poisoning
happens 2-8 weeks after exposure:
- Paresthesia
- Numbness
- Pain
Describe the effects of chronic arsenic exposure
- Hyperpigmentation (arsenic binds keratin & increases cell prolif)
- Hyperkeratosis (Hands)
- Patchy hair loss
- Increase cancer risk
Describe the high cancers seen in arsenic poisoning
Defective nucleotide excision repair:
- Squamous cell carcinoma
- Basal cell carcinoma
- Bowens disease
Describe Bowens disease
Painless ulcers on the palms
Precancerous squamous cell carcinoma
Meese lines (nails)
Suspect HPV (if sexually promiscuous) or arsenic
Describe the features of Cadmium toxicity
It’s toxic to the kidney & lung epithelium causing alveolar necrosis (Obstructive lung disease) & proximal tubular necrosis (Chronic renal disease)
Presents with flu symptoms (fever, weakness, chills) osteomalacia, & osteoporosis
List some sources of Cadmium
Mining
Electroplating
Nickel-Cadmium battery factories
Soil
Plants/fertilizers
Ceramic food containers
Which 2 conditions does cadmium toxicity lead to?
Obstructive lung disease & Chronic renal disease
Acute exposure to Cadmium causes
flu-like symptoms (weakness, fever, headache, chills, sweating, & muscular pain)
Long term exposure to cadmium can lead to
- Lung cancer or obstruction
- Kidney damage or chronic kidney disease
- Pulmonary emphysema
- Bone disease (osteomalacia & osteoporosis)
93) A 52-year-old man visited ER complaining of coughing, shortness of breath and brown
expectorant for past 3 months. He works as a security guard and lives in the basement of
house, downtown, Chicago for the past 15 years. He smokes occasionally and social drinker. CT
scan showed mass in the right bronchus. Biopsy from the mass confirmed Squamous Cell
Carcinoma. Most likely risk factor for developing the cancer in this patient is due to.
A) Legionella pneumophila
B) Air pollution
C) Cigarette smoking
D) Arsenic toxicity
E) Radon
E) Radon
