Lead is the major cause of heavy-metal toxicity in present-day society. Lead is found in storage batteries and was used as a constituent of paint and gasoline for many years. The most common causes of lead poisoning in the U.S. are ingestion of lead-based paint and industrial or environmental exposure. The symptoms of chronic lead poisoning are abdominal cramps, vomiting, constipation, lethargy, anemia, weight loss, muscle paralysis, nephropathy, and convulsions. Death is uncommon. When it does occur, it most often involves children in tenement areas who have a history of pica. These children, ages 18 months to 3 years, eat the lead-containing paint peelings that fall off the walls of their homes. Lead deposited in the bone produces a dense band at the ends of the long bones that can be seen on X-ray. Deaths of these children peak during the summer. At autopsy, the most striking finding is the brain, which is massively swollen, with flattening of the gyri, and is extremely pale, almost white. Blood smears show basophilic stippling of erythrocytes. Characteristic eosinophilic intranuclear inclusions may be seen in hepatocytes and cells of the proximal tubules of the kidneys (Figure 23.3). PAS-positive, pink-staining homogeneous material may be seen in the perivascular spaces in the brain.
In adults, 0.20 mg/L in venous blood is now considered the normal upper limit for blood lead. The upper limit of normal for lead in venous blood for children is 0.10 mg/L. Children with lead levels between 0.10 and 0.20 mg/L usually require observation with follow-up venous testing every 2 to 3 months, because levels can continue to rise. Children whose blood lead levels are >= 0.20 mg/L need clinical management, including a detailed environmental, nutritional, and medical history. Generally, levels >= 0.45 mg/L are treated with chelation, the removal of lead from the blood. Some physicians, however, order chelation with levels as low as 0.3 mg/L.14
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Did you ever think feeling angry and irritable could be a symptom of constipation? A horrible fullness and pressing sharp pains against the bladders can’t help but affect your mood. Sometimes you just want everyone to leave you alone and sleep to escape the pain. It is virtually impossible to be constipated and keep a sunny disposition. Follow the steps in this guide to alleviate constipation and lead a happier healthy life.