Acute leukemia is a malignant proliferation of white blood cell (WBC) precursors (blasts) in bone marrow or lymph tissue and their accumulation in peripheral blood, bone marrow, and body tissues.
The most common forms are acute lymphoblastic (lymphocytic) leukemia (ALL), characterized by the abnormal growth of lymphocyte precursors (lymphoblasts); acute myeloblastic (myelogenous) leukemia (AML), in which myeloid precursors (myeloblasts) rapidly accumulate; and acute monoblastic (monocytic) leukemia, or Schilling’s type, characterized by a marked increase in monocyte precursors (monoblasts). Other variants include acute myelomonocytic leukemia and acute erythroleukemia.
Untreated, acute leukemia is invariably fatal, usually because of complications that result from leukemic cell infiltration of bone marrow or vital organs. With treatment, the prognosis varies.
With ALL, treatment induces remissions in 90% of children (average survival time is 5 years) and in 65% of adults (average survival time is 1 to 2 years). Children ages 2 to 8 have the best survival rate with intensive therapy.
With AML, the average survival time is only 1 year after diagnosis, even with aggressive treatment. With acute monoblastic leukemia, treatment induces remissions lasting 2 to 10 months in 50% of children; adults survive only about 1 year after diagnosis, even with treatment.
Research on predisposing factors is inconclusive, but points to some combination of viruses (viral remnants have been found in leukemic cells), genetic and immunologic factors, and exposure to radiation and certain chemicals.
Pathogenesis isn’t clearly understood, but immature, nonfunctioning WBCs appear to accumulate first in the tissue where they originate (lymphocytes in lymph tissue, granulocytes in bone marrow). These immature WBCs then spill into the bloodstream and from there infiltrate other tissues, eventually causing organ malfunction because of encroachment or hemorrhage. (See What happens in leukemia.)
Acute leukemia is more common in males than in females, in whites (especially people of Jewish descent), in children between ages 2 and 5 (80% of all leukemias in this age-group are ALL), and in people who live in urban and industrialized areas. Acute leukemia ranks 20th in causes of cancer-related deaths among people of all age-groups. Among children, however, it’s the most common form of cancer.
Signs and symptoms of acute leukemia are the sudden onset of high fever accompanied by thrombocytopenia and abnormal bleeding, such as nosebleeds, gingival bleeding, purpura, ecchymoses, petechiae, easy bruising after minor trauma, and prolonged menses. Nonspecific signs and symptoms — such as low-grade fever, weakness, and lassitude — may persist for days or months before visible signs appear.
Other insidious signs and symptoms include pallor, chills, and recurrent infections. In addition, ALL, AML, and acute monoblastic leukemia may cause dyspnea, anemia, fatigue, malaise, tachycardia, palpitations, systolic ejection murmur, and abdominal or bone pain. When leukemic cells cross the blood-brain barrier and thereby escape the effects of systemic chemotherapy, the patient may develop meningeal leukemia, characterized by confusion, lethargy, and headache.
Typical signs and symptoms and bone marrow aspirate showing a proliferation of immature WBCs confirm acute leukemia. An aspirate that’s dry or free from leukemic cells in a patient with typical signs and symptoms requires a bone marrow biopsy, usually of the posterior superior iliac spine.
Blood counts show thrombocytopenia and neutropenia. A differential leukocyte count determines cell type. Lumbar puncture detects meningeal involvement.
Systemic chemotherapy aims to eradicate leukemic cells and induce remission. Chemotherapy varies according to the type of leukemia:
❑ meningeal leukemia — intrathecal instillation of methotrexate or cytarabine with cranial radiation is used.
❑ ALL — vincristine, prednisone, methotrexate, 6-mercaptopurine, and cyclophosphamide are used. Intrathecal therapy may be required. Radiation therapy is given for testicular infiltration.
❑ AML — a combination of I.V. chemotherapeutic drugs is used. In acute promyelocytic leukemia, a type of AML, all-trans retinoic acid is used to cause leukemia cells to mature into normal WBCs. It’s used in remission and increases the cure rate of AML. If this drug fails, arsenic trioxide may help.
❑ acute monoblastic leukemia — cytarabine and thioguanine with daunorubicin or doxorubicin is used.
A bone marrow or stem cell transplant may be possible. Treatment also may include antibiotic, antifungal, and antiviral drugs and granulocyte injections to control infection. Platelet transfusions (to prevent bleeding) and red blood cell transfusions (to prevent anemia) may also be given.
❑ For the patient with leukemia, goals of therapy include promoting comfort, minimizing the adverse effects of chemotherapy, preserving the veins, managing complications, and providing teaching and psychological support. Because so many of these patients are children, be especially sensitive to their emotional needs and those of their families.
Before treatment:
❑ Explain the course of the disease, treatments, and adverse effects of prescribed drugs.
❑ Teach the patient and his family how to recognize infection (fever, chills, cough, sore throat) and abnormal bleeding (bruising, petechiae) and how to stop such bleeding (applying pressure and ice to the area).
❑ Promote good nutrition. Explain that chemotherapy may cause weight loss and anorexia, so encourage the patient to eat and drink high-calorie, high-protein foods and beverages. However, chemotherapeutic drugs and prednisone may cause weight gain, so dietary counseling and teaching are helpful.
❑ Help establish an appropriate rehabilitation for the patient during remission.
For supportive care:
❑ Watch for signs and symptoms of meningeal leukemia (confusion, lethargy, headache). If these occur, know how to manage care after intrathecal chemotherapy. After such instillation, place the patient in Trendelenburg’s position for 30 minutes. Give the patient plenty of fluids, and keep him in a supine position for 4 to 6 hours.
❑ Check the lumbar puncture site often for bleeding.
❑ If the patient receives cranial radiation, teach him about potential adverse effects, and do what you can to minimize them.
❑ Prevent hyperuricemia, which may result from rapid chemotherapy-induced leukemic cell lysis. Give the patient about 2 qt (2 L) of fluids daily, and administer acetazolamide, sodium bicarbonate tablets, and allopurinol. Check urine pH often — it should be above 7.5. Watch for a rash or another hypersensitivity reaction to allopurinol.
❑ If the patient receives daunorubicin or doxorubicin, watch for early signs of cardiotoxicity, such as arrhythmias, and signs of heart failure.
❑ Control infection by placing the patient in a private room and imposing reverse isolation, if necessary. (The benefits of reverse isolation are controversial.) Coordinate patient care so the patient doesn’t come in contact with staff who also care for patients with infections or infectious diseases. Avoid using indwelling urinary catheters and giving I.M. injections because they can cause infection. Screen staff and visitors for contagious diseases, and watch for signs of infection.
❑ Provide thorough skin care by keeping the patient’s skin and perianal area clean, applying mild lotions or creams to keep skin from drying and cracking, and thoroughly cleaning skin before all invasive skin procedures. Use strict aseptic technique and a metal scalp vein needle (metal butterfly needle) when starting I.V. lines. If the patient receives total parenteral nutrition, provide scrupulous subclavian catheter care.
❑ Monitor the patient’s temperature every 4 hours.
CLINICAL TIP: A patient with a temperature over 101° F (38.3° C) and a decreased WBC count should receive prompt antibiotic therapy.
❑ Watch for bleeding; if it occurs, apply ice compresses and pressure, and elevate the extremity. Avoid giving I.M. injections, aspirin, and aspirin-containing drugs. Also avoid taking rectal temperatures, giving rectal suppositories, and performing digital examinations.
❑ Prevent constipation by providing adequate hydration, a high-residue diet, a stool softener, and a mild laxative and by encouraging walking.
❑ Control mouth ulceration by checking often for obvious ulcers and gum swelling and by providing frequent mouth care and saline rinses.
❑ Tell the patient to use a soft toothbrush and to avoid hot, spicy foods and overuse of commercial mouthwashes. Also, check the rectal area daily for induration, swelling, erythema, skin discoloration, or drainage.
❑ Minimize stress by providing a calm, quiet atmosphere that’s conducive to rest and relaxation. For children particularly, be flexible with patient care and visiting hours to promote maximum interaction with family and friends and to allow time for schoolwork and play.
❑ For those patients who are refractory to chemotherapy and in the terminal phase of the disease, supportive nursing care aims to provide comfort; management of pain, fever, and bleeding; and patient and family support. Provide the opportunity for religious counseling. Discuss the option of home or hospice care. Support groups, such as the American Cancer Society, may also be helpful.
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Copyright notice for book excerpts: Copyright © 2008 Lippincott Williams & Wilkins. All rights reserved.
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More About This Book:
Title: Handbook of Diseases Authors: Springhouse Publisher: Lippincott Williams & Wilkins Copyright: 2003 ISBN: 1-58255-266-5 
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