Pathophysiology.

The most common nutritional deficiency of children in the United States today is anemia caused by insufficient amounts of iron in the body. The incidence is highest during infancy and adolescence—two rapid growth periods. Anemia (an, “without,” and emia, “blood”) is a condition in which there is a reduction in the amount and size of the RBCs or in the amount of hemoglobin, or both. Iron-deficiency anemia may be caused by severe hemorrhage, the child’s inability to absorb the iron received, excessive growth requirements, or an inadequate diet. Researchers have also found that feeding whole cow’s milk to infants can precipitate gastrointestinal bleeding, resulting in anemia.

Prevention of iron-deficiency anemia begins with good prenatal care to ensure that the mother has a suitable intake of iron during pregnancy. During the first few months after birth, the newborn relies on iron that was stored in the system during fetal life. Preterm infants may be deprived of a sufficient supply, because iron is obtained late in the prenatal period. In addition, the iron stores of low-birth-weight infants and infants from multiple births are relatively small.

The highest incidence of iron-deficiency anemia occurs from the ninth to the twenty-fourth month. During this rapid growth period, the infant outgrows the limited iron reserve that was in the body; in addition, iron-fortified formula and infant cereals may have been eliminated from the diet. Poorly planned meals or feeding problems also contribute to this deficiency. The mother may sometimes rely too heavily on bottle feedings to avoid conflict at meals. Unfortunately, milk contains very little iron. Instead, the amounts of solid food should be increased and the amount of milk decreased. Boiled egg yolk, liver, leafy green vegetables, Cream of Wheat, dried fruits (apricots, peaches, prunes, raisins), dry beans, crushed nuts, and whole-grain bread are good sources of iron. Iron-fortified cereals eaten out of the box provide a nutritious snack. Unfortunately, not all the iron found in a food source is absorbed by the body. The bioavailability of iron in vegetables is less than that in meat.

Manifestations.

The symptoms of iron-deficiency anemia are pallor, irritability, anorexia, and a decrease in activity. Many infants are overweight because of excessive consumption of milk (so-called “milk babies”). Blood tests for anemia may include RBC count, hemoglobin and hematocrit levels, and determination of morphological cell changes and iron concentration. The stool may be tested for occult blood. A dietary history is also obtained. Sometimes a slight heart murmur is heard. The spleen may be enlarged.

Untreated iron-deficiency anemias progress slowly, and in severe cases the heart muscle becomes too weak to function. If this happens, heart failure follows. Children with long-standing anemia may also show growth retardation and cognitive changes. Screening procedures are suggested at 9 and 24 months for full-term infants and earlier for low-birth-weight infants.

Treatment.

Iron-deficiency anemia responds well to treatment. Iron, usually ferrous sulfate, is given orally two or three times a day between meals. Vitamin C aids in the absorption of iron; therefore giving juice when administering iron is suggested. Liquid preparations are taken through a straw to prevent temporary discoloration of the teeth. (Some iron preparations without this disadvantage are available.) The toddler needs solid foods that are rich sources of iron. An iron-dextran mixture (Imferon) given intramuscularly is also highly effective. It must be injected deep in a large muscle using the Z-track technique to minimize staining and tissue irritation.

Parent Education.

Parents need explicit instructions on proper foods for the infant. The nurse stresses the importance of breastfeeding for the first 6 months and the use of iron-fortified formula throughout the first year of life (the absorption of iron from human milk is much better than from cow’s milk). The amount of milk consumed during the day and night is determined. Solid food intake is reviewed, and specific iron-enriched nutrients are suggested. The nurse considers financial, ethnic, and family preferences in teaching plans. Behavior concerns at mealtime may also have to be addressed.

Pathophysiology.

Sickle cells contain an abnormal form of hemoglobin termed hemoglobin S (the sickling type). The membranes of these cells are fragile and easily destroyed. Their crescent shape makes it difficult for them to pass through the capillaries, causing a pileup of cells in the small vessels. This clumping may lead to a thrombosis (clot) and cause an obstruction. Infarcts, or areas of dead tissue, may result when the tissue is denied proper blood supply. These generally develop in the spleen but may also be seen in other areas of the body, such as the brain, heart, lungs, gastrointestinal tract, kidneys, and bones. The patient feels acute pain in the affected area.

There are two types of sickle cell disease: an asymptomatic (a, “without,” and symptoma, “symptom”) version (sickle cell trait) and much more severe forms that necessitate intermittent hospitalization (sickle cell anemia).

Diagnosis.

Sickle cell disease can be detected before birth by chorionic villi sampling. Early diagnosis by mandatory screening of all newborns in the United States allows early detection before symptoms occur. The sickling test (Sickledex) is commonly used for screening. Hemoglobin electrophoresis (“fingerprinting”) is used when the result is positive. This procedure separates and records the various peptide patterns of the blood. It distinguishes between patients with the trait and those with the disease.

Treatment and Nursing Care.

When the infant or child is hospitalized during a crisis, the treatment is supportive and symptomatic. The patient is confined to bed. Analgesics are given to relieve pain. Children in severe pain may need a continuous intravenous (IV) infusion containing a narcotic. Meperidine (Demerol) is not recommended for children with sickle cell disease because of the risk of normeperidine-induced seizures (National Institutes of Health [NIH], 2002). A patient-controlled analgesia (PCA) pump enables children older than 7 years to maintain control and participate in care. Every effort is made to combat dehydration and acidosis. Small blood transfusions may be administered to increase the hemoglobin count, but the results are only temporary. Packed RBCs are often given for this purpose. An accurate record of intake and output is kept. The patient’s body position is changed frequently but gently. Hemopoietic stem cell transplantation may provide a cure in the near future.

Sickle cell disease may take a wide variety of courses. As always, the individual patient’s progress is followed. Sometimes it is difficult to distinguish between abdominal pain caused by a sickle cell crisis and abdominal pain caused by appendicitis. The nurse must remember that pain experienced by a child with sickle cell disease may also be caused by an unrelated condition.

Prevention of infection and prevention of dehydration are important goals in the care of a child with sickle cell disease. Pneumococcal and meningococcal vaccinations and annual influenza vaccination are recommended. Oral penicillin prophylaxis before any invasive treatment, including dental care, is also advised (NIH, 2002). Multiple transfusions of packed cells may be required to maintain adequate hemoglobin levels. The nurse should observe the child for reactions to the blood transfusion. Hemosiderosis (the deposit of iron into organs and tissues in the body) is a complication of this type of hemolytic disease. An exchange transfusion may reduce the number of circulating sickle cells and prevent complications such as thrombus formation and stroke. High-dose IV methylprednisolone may be used to decrease severe pain (Dover & Platt, 2003).

The main goals of therapy are to prevent sickling, dehydration, hypoxia, and infection, which can cause a sickle cell crisis. Erythropoietin and some chemotherapy regimens can increase the production of fetal hemoglobin and reduce complications. Bone marrow transplantation and gene replacement therapy may hold a promising cure (Jackson et al., 2009).

Surgery.

The use of splenectomy in children with sickle cell disease has been conservative. A recurrence of acute splenic sequestration becomes less likely after age 5 years. Routine splenectomy is not recommended because the spleen generally atrophies on its own because of fibrotic changes that take place in patients with sickle cell disease.

Pathophysiology.

The thalassemias are a group of hereditary blood disorders in which the patient’s body cannot produce sufficient adult hemoglobin. The RBCs are abnormal in size and shape and are rapidly destroyed. This abnormality results in chronic anemia. The body attempts to compensate by producing large amounts of fetal hemoglobin. Thalassemias are caused by a deficiency in the normal synthesis of hemoglobin polypeptide chains. They are categorized according to the Greek letters designating the polypeptide chain affected as α-, β-, γ-, or δ-thalassemia.

The most common variety of thalassemia involves impaired production of beta chains and is known as β-thalassemia. This variety consists of two forms: thalassemia minor and thalassemia major. Thalassemia major is also called Cooley’s anemia. Thalassemia occurs mainly in persons of Mediterranean origin, such as Greeks, Syrians, and Italians, and their descendants elsewhere. The term is derived from the Greek thalassa, which means “sea.” Thalassemia can also occur from spontaneous mutations.

Treatment and Nursing Care.

The goals of care for children with thalassemia are to (1) maintain hemoglobin levels at 9.5 g/dL to prevent overgrowth of bone marrow and resultant deformities and (2) provide for growth and development and normal physical activity. Prevention or early treatment of infection is important. Some patients require splenectomy. Bone marrow transplantation holds promise for the future treatment of this condition (Jackson et al., 2009).

The mainstay of treatment for thalassemia major is frequent blood transfusions to maintain the hemoglobin level above 9.5 g/dL. As a result of repeated blood transfusions, excessive deposits of iron may be stored in the tissues. This is termed hemosiderosis and is seen especially in the spleen, liver, heart, pancreas, and lymph glands. Deferoxamine mesylate (Desferal), an iron-chelating agent, is given to counteract hemosiderosis. Severe splenomegaly may occur in some children. Splenectomy may make the patient more comfortable, increase the ability to move about, and allow for more normal growth. After surgery, these children are given prophylactic antibiotics to prevent infection.

Pathophysiology.

Hemophilia is one of the oldest hereditary diseases known to humanity. In this disorder the blood does not clot normally, and even the slightest injury can cause severe bleeding. It has been called the disease of kings because it has occurred in the children of several royal families in Russia and Europe. This congenital disorder is confined almost exclusively to males but is transmitted by symptom-free females.

Hemophilia is inherited as a sex-linked recessive trait. It is termed sex-linked because the defective gene is located on the X, or female, chromosome. Different combinations of genes account for the fact that some children inherit the disease, some become carriers, and others neither inherit nor carry the trait. New mutations do occur, and the reason for this is unclear. The sex of the fetus can be determined by amniocentesis. Fetal blood sampling detects hemophilia. Some carrier women can also be identified.

There are several types of hemophilia. More than 10 identified factors in blood are involved in the clotting mechanism. A deficiency in any one of the factors will interfere with normal blood clotting. The two most common types of hemophilia are hemophilia B, or Christmas disease (a factor IX deficiency), and hemophilia A (a deficiency in factor VIII). This discussion is limited to classic hemophilia, or hemophilia A, which accounts for approximately 84% of cases.

Hemophilia A is caused by a deficiency of coagulation factor VIII, or antihemophilic globulin (AHG). The severity of the disease depends on the level of factor VIII in the plasma of the patient’s blood. Some patients’ lives are endangered by minor injury, whereas a child with a mild case of hemophilia might just bruise a little more easily than the normal person. The degree of severity tends to remain constant within a given family. The aim of therapy is to increase the level of factor VIII high enough to ensure clotting. It is possible to determine the level of factor VIII in the blood by means of a test called the partial thromboplastin time (PTT), which can help to diagnose and assess the child’s condition. Prenatal diagnosis by amniocentesis is possible.