Clinical Consequences of Toxic Exposure
The line on the gums of this 30-year-old man indicates lead poisoning. The patient had been employed for 8 months at a lead smelting plant in which no occupational safety precautions had been enforced. He was admitted to the hospital with the classic symptoms and signs of lead poisoning--pain in the nape of the neck that radiated down the spine, posterior thighs, and calves to the plantar aspect of the feet; colicky panabdominal pain; anorexia; weight loss; nausea; vomiting; constipation; bone and muscle tenderness; hyperesthesia of all extremities; insomnia; irritability; generalized weakness; malaise; and dizziness.
The patient acknowledged habitual finger chewing, and biting and eating his nails (pica), which contributed to his lead exposure. No foot or wrist drop was evident. His serum free-lead level was 96 µg/dL. A peripheral blood smear revealed hypochromia, microcytosis, and basophilic stippling. The free erythrocyte protoporphyrin level was 230 µg/dL. Urinalysis was normal.
Treatment with edetate calcium disodium followed by d-penicillamine produced excellent results in this case.
A minimally responsive 26-year-old man was brought to the emergency department after being found in his home by a friend. A suicide note lay next to his body. The patient had a history of depression. He was lethargic with decreased respirations.
Multiple metallic densities scattered throughout the lungs were evident on an anterior chest film and a lateral view. Densities overlying the heart and the superior mediastinum were also seen. These findings indicate the presence of mercury within the right ventricle.
The patient's note revealed that he had injected himself with about 10 mL of mercury obtained from thermometers and an old thermostat. He had harvested the mercury, placed the liquid in a syringe, and injected it into an antecubital vein.
The main complication of acute mercury poisoning is renal failure; the patient underwent chelation therapy and received supportive care. He was discharged from the hospital 10 days after admission and referred for outpatient psychiatric therapy. The patient experienced no long-lasting sequelae from the mercury poisoning.
Prolonged occupational/environmental exposure to arsenic caused these brown, rough, palmar papules. Similar lesions were present on the patient's sole. These arsenical keratoses were the result of contact with agricultural arsenic-containing insecticides and probable exposure to arsenic-laden well water.
Arsenical keratoses should prompt a thorough search for cutaneous carcinoma; this patient had several basal cell epitheliomas in non-sun-exposed areas. In addition, such patients may be at increased risk for respiratory, GI, or genitourinary malignancy many decades after arsenic exposure.