American Medical Association Family Medical Guide - American Medical Association [199]
The condition occurs most often in late fall and winter, affecting mostly children between ages 2 and 7, boys more frequently than girls. Severe cases can lead to kidney failure (see page 817), bleeding into the intestinal tract and other organs, and, rarely, intestinal obstruction (intussusception; see page 406). In some children, allergic purpura can recur for up to 2 years before it finally disappears for good.
Symptoms
Allergic purpura usually starts as an itchy skin rash that is purplish red, irregularly shaped, flat or raised, and can vary in size, resembling bruises. The spots usually appear on the ankles, shins, buttocks, and elbows. The spots tend to come and go and fade after several weeks. In some people, the rash is preceded by a sore throat, headache, fever, and loss of appetite.
Some children also may have swollen joints (usually the ankles or the knees), abdominal pain that is often severe and persistent, and blood in the stool. About half have blood in their urine and a low volume of urine, which, in severe cases, can indicate widespread obstruction of the tiny blood vessels (capillaries) in the filtering structures (glomeruli) of the kidneys (glomerulonephritis; see page 807). Some children may develop high blood pressure.
Diagnosis and Treatment
Allergic purpura is diagnosed by the symptoms, a physical examination, a thorough health history, and blood and urine tests. X-rays or CT scans may be performed to evaluate any complications that develop in the intestines or other organs. In most cases, treatment is not necessary because the condition tends to clear up on its own within a month, but a child may be hospitalized to watch for serious complications. For severe cases, a doctor may prescribe corticosteroids to reduce inflammation, or intravenous gamma globulin (which contains antibodies to fight infection) to alleviate symptoms.
If the kidneys are affected, the doctor will want to see the child for regular checkups to monitor the health of the kidneys. In some cases, a doctor may do a kidney biopsy (microscopic examination of a sample of tissue from the kidney). Elevated levels of blood or protein in the urine may persist for months in some children; these symptoms also require follow-up checkups. If the child develops high blood pressure, the doctor will prescribe medication to control it.
Iron Deficiency Anemia in Children
Iron deficiency anemia, the most common form of anemia in children, results from an insufficient supply of hemoglobin (the oxygen-carrying protein) in the blood. The disorder usually results from an insufficient intake of iron in the diet or from poor absorption of iron by the body. Most full-term babies are born with an adequate supply of iron from their mother during pregnancy and receive iron from breast milk or formula. However, as the child grows and has an increased need for iron, a diet deficient in iron can lead to anemia. Preterm infants, who often are born with an inadequate supply of iron, and children who have a disorder that inhibits iron absorption, such as celiac disease (see page 768), have an increased risk of developing anemia. Infants should not drink cow’s milk because it interferes with the absorption of iron and irritates the intestinal lining, causing intestinal bleeding and further contributing to anemia.
Symptoms
Mild anemia usually causes no obvious symptoms. In more severe cases, symptoms can include pale skin (especially on the hands and inside the lower eyelids), fatigue, weakness, or behavioral changes such as irritability or anger. Less often, fainting, breathlessness, and heart palpitations may occur. All of these symptoms are more obvious after physical activity. If your child is less active than usual or if he or she is breathless after even moderate activity, see your doctor. If you suspect that your child may have anemia, do not try to treat it yourself with iron supplements, because too much