Blood

A father brings in his 6-year-old son to the clinic who is taking induction chemotherapy for ALL. The school will not allow the child to register until his immunizations are up to date. The best course of action is to:

  1. Call the school nurse or principal to inform them that this child cannot receive immunizations while he is taking chemotherapy.
  2. Update all immunizations except for measles-mumps-rubella (MMR) and varicella.
  3. Update all immunizations except for oral polio vaccine.
  4. Update all immunizations.
  5. Call the school nurse or principal to inform them that this child will never receive immunizations because of the alter­ation in his immune system.

A. Live virus vaccines are contraindicated for the child with ALL (and all members of the household) during chemotherapy and for at least 6 months after completion of treatment. Al­though the viruses in the MMR and varicella vaccine are atten­uated, immunosuppression from treatment can be profound and actual viral disease can result. While immunizations that do not contain live virus (diphtheria, tetanus, inactivated poliovirus vaccine, hepatitis B, hepatitis A) are not directly contraindicated for the child receiving chemotherapy, the associated immunosuppression often inhibits antibody responses so he mostly will not benefit from these vaccines.

Two weeks after a viral syndrome, a 2-year-old develops bruis­ing and generalized petechiae, more prominent over the legs. He has neither hepatosplenomegaly nor lymph node enlargement. Laboratory testing reveals a normal hemoglobin, hematocrit, and white blood cell count and differential. The platelet count is 15,000/mm3. The most likely diagnosis is:

  1. Von Willebrand disease
  2. Acute lymphoblastic leukemia
  3. Immune thrombocytopenia
  4. Aplastic anemia
  5. Thrombotic thrombocytopenic purpura

C. In children, immune thrombocytopenic purpura (ITP) is the most common form of thrombocytopenic purpura. In most cases a preceding viral infection can be documented. The platelet count is frequently less than 20,000/mm3, but other lab­oratory tests yield normal results. In patient wit normal clinical finding and one cell line affected, other options are not valid.

A 16-year-old Alaskan adolescent girl comes to the office for an evaluation of lethargy. Her father notes that recently she seemed pale. She eats a regular diet and has no significant past medical history. Her menses are regular and have not changed. During the last 2 years she has helped her mother in the family seafood restaurant after school. Her complete blood count reveals a megaloblastic anemia. The next appropriate study is:

    1. Stool for ova and parasites
    2. Transcobalamin levels
    3. Iron levels
    4. Gastric endoscopy
    5. Hypoxanthine-guanine phosphribosyltransferase (HI assay for Lesch-Nyhan syndrome

A. The fish tape worm Diphyllobothrium latum uses vitamin B12 for growth and egg production as many as I million eggs a day may be produced. The parasite also inactivates the BI2 intrinsic factor complex, inhibiting absorption in the terminal ileum. The fish tapeworm is the longest tapeworm to infect hu­mans, sometimes growing to more than 10 meters in length. In 2% to 9% of infestations, megaloblastic anemia may result; oth­erwise, most infestations are asymptomatic. Risk factors in­clude eating raw or undercooked fish. In North America, it is most commonly seen in the northern United States, Alaska, and Canada. Eggs have a unique morphology and are easily found in stool samples

A 3-year-old plump, healthy-appearing toddler comes to your office for her health maintenance examination. In discussing her dietary history with her mother, you find that the child refuses solid food, instead preferring to drink cow’s milk almost exclusively. The parents tried to cut her off once but could not endure the subsequent whining and gave in to her de­mands for milk. Her blood pressure, heart rate, and respiratory effort are normal. Her complete blood count is significant for hemoglobin of 7 g/dL and an MCV of 60 fL (normal 70-90). Appropriate therapy should include:

    1. Transfusion of packed red blood cells to get her to a normal hemoglobin, and then initiation of oral iron replacement.
    2. Discussion with the family about dietary changes, and then initiation of oral iron replacement.
    3. Intramuscular iron injection and follow-up visit in 1 week.
    4. Hospital admission to monitor vital signs.
    5. Reassuring the parents that the behavior and laboratory findings are normal.

B. The child in the question has iron deficiency secondary to ex­cessive cow’s milk ingestion. Cow’s milk contains little iron. The child’s vital signs are normal, suggesting transfusion of blood is not necessary. Intramuscular iron can cause fever, ana­phylaxis, hypotension, rash, and arthralgias; oral replacement is preferred. The best long-term management is dietary counseling for the family.

You are caring for a child with homozygous beta-thalassemia (thalassemia major) who requires monthly blood transfusions. What ongoing medication is vital to the health of this patient?

    1. Penicillin
    2. Iron
    3. Hydroxyurea
    4. Iron chelators
    5. Prednisone

D. Patients requiring hypertransfusion will ultimately develop hemosiderosis if not treated with the iron-chelating medication. Each unit of packed red blood cells delivers 200 mg of iron; left untreated, the patient develops a significant iron overload with high morbidity and mortality..

A father brings his 10 years old child to you for evaluation of a rash and fatigue. The child was healthy until about 2 months ago when he first developed a vesicular rash and swelling in his right foot. The rash seemed to coincide with a barefoot run through the family’s farm, so the father thought lit­tle of it. At about the same time as the rash developed the child developed a cough. The father reports that while the cough has resolved the child has seemed ill and has not been able to do his chores. The boy has had occasional abdominal pain and diar­rhea, but has no specific complaint today aside from fatigue. His physical examination is significant for pallor and mild ab­dominal tenderness without rebound. Laboratory studies reveal a microcytic, hypochromic anemia with an elevated percentage of eosinophils. The next step in arriving at this patient’s diagnosis is:

  1. Iron studies
  2. Hemoglobin electrophoresis
  3. Serum chemistries
  4. Vitamin B 12 level
  5. Stool for ova and parasites.

E. This patient is on a farm, has been barefoot, developed a rash in his feet, developed cough, and now has microcytic anemia with eosinophilia. He is likely infected with a hookworm. Routine microscopy on a stool specimen for eggs will confirm that.

A 2-year-old girl presents with new onset rash. She was well until 2 weeks prior when she had fever and upper respiratory symptoms that resolved without treatment. She has not had fever since and has continued to be playful and active. Upon ex­amination she has petechiae on her upper and lower extremities and trunk. Her platelet count is 25,000/mm3, her white blood cell count and hemoglobin are normal. Which of the following is the best next step in management?

  1. Obtain a review of the peripheral blood smear.
  2. Administer intravenous immunoglobulin.
  3. Send a blood culture and begin empiric antimicrobial therapy.
  4. Order a platelet transfusion.
  5. Arrange for bone marrow biopsy.

A. This child has classic features of ITP: isolated thrombocy­topenia in a well-appearing child. A thorough physical exami­nation and peripheral blood smear are necessary. If the child does not have lymphadenopathy or organomegaly and the pe­ripheral blood smear is normal, initial management includes close observation and a protective environment.

A l4-year-old girl presents with a rash on her arms and legs. She was diagnosed with a urinary tract infection 4 days ago, which is being treated with trimethoprim-sulfamethoxazole. She denies fever, vomiting, diarrhea, headache, and dysuria. Her examination is remarkable for multiple petechiae on her up­per and lower extremities. Her white blood cell count and he­moglobin are normal and her platelet count is 35,000/mm3. The next step in management is to:

  1. Send blood for antinuclear antibody (ANA).
  2. Send a repeat urinalysis.
  3. Discontinue the trimethoprim-sulfamethoxazole.
  4. Obtain HIV testing.
  5. Administer intravenous immunoglobulin.

C.This patient’s thrombocytopenia may be a result of the use of  trimethoprim-sulfamethoxazole. The medication should be dis­continued and her platelet count should be monitored. If she has continued thrombocytopenia after the medication is discontin­ued, she may have ITP and must also be followed for possible chronic ITP. Chronic ITP occurs in older children with a female predominance and may be associated with systemic lupus ery­thematosus or with chronic infections.

A l4-year-old girl presents with a rash on her arms and legs. She was diagnosed with a urinary tract infection 4 days ago, which is being treated with trimethoprim-sulfamethoxazole. She denies fever, vomiting, diarrhea, headache, and dysuria. Her examination is remarkable for multiple petechiae on her up­per and lower extremities. Her white blood cell count and he­moglobin are normal and her platelet count is 35,000/mm3. The next step in management is to:

  1. A complete blood count is likely to reveal thrombocytosis.
  2. Initial therapy includes systemic corticosteroids.
  3. Empiric antimicrobial therapy for sepsis should be initiated.
  4. An emergent oncology consultation for probable leukemia should be arranged.
  5. The serum creatinine is likely to be elevated.

E. This child has features of hemolytic-uremic syndrome, which frequently follows a bout of gastroenteritis; it has been associated with Escherichia coli OI57:H7, Shigella and Sal­monella. Patients present with pallor, lethargy, and decreased urine output; some may have hepatosplenomegaly, petechiae, and edema. Hematologic laboratory findings include hemolytic anemia and thrombocytopenia; peripheral blood smear reveals helmet cells, burr cells, and fragmented red blood cells. Acute renal failure of HUS is manifested by hematuria, proteinuria, and elevated serum creatinine. Management is largely support­ive with careful monitoring of renal and hematologic parameters. With significant renal disease, peritoneal dialysis may be required.

A 2-year-old African American girl presents to the emergency center with a complaint of sudden onset of abdominal pain and weakness. She is afebrile but is tachypneic and tachycardic. Her mucus membranes are pale. Lung sounds are clear. A systolic murmur is noted at the base of the heart. The spleen tip is palpable 2 cm below the right costal margin. The initial work-up for this patient should include:

  1. Electrocardiogram
  2. Chest radiograph
  3. Magnetic resonance imaging (MRI) of the abdomen
  4. Complete blood count with peripheral smear
  5. Liver function tests.

D. The most likely and also the most urgent diagnosis for this child is splenic sequestration crisis in a patient with sickle cell disease. Rapid pooling of blood in the spleen, can lead to hypovolemia with significant morbidity and even death if not ad­dressed quickly. This child’s heart murmur is most likely due to chronic anemia associated with sickle cell disease.

The parents of a previously healthy 3-year-old bring the child to your office because she is complaining that her tongue hurts. The parents also report she has seemed weak and listless over the last several months and has not been eating well. Just recently she has had trouble walking. The family usually eats regular diet including meats and vegetables. On physical examination her tongue is smooth, red, and tender. She is pale and tachycardic. Her complete blood count reveals a macrocytic anemia. The most likely diagnosis in this child is:

  1. Iron deficiency
  2. Nutritional deficiency
  3. Transcobalamin deficiency
  4. Juvenile pernicious anemia
  5. Folate deficiency

D. This is the typical presentation for juvenile pernicious ane­mia, a rare autosomal recessive condition in which the child is not able to secrete intrinsic factor and thus cannot absorb vita­min B12. Supplies of vitamin BI2 passed to the fetus from the mother are typically sufficient for at least the first year or two of life. A deficiency in transcobalamin results in megaloblastic anemia in infancy, as transcobalamin is required for BI2 trans­port and utilization; therefore, the vitamin B12 provided by the mother cannot be used effectively.

You are asked to see a patient in consultation with his primary doctor. The 2-year-old boy was admitted to the hospital this morning with severe iron-deficiency anemia (hemoglobin of 2 g/dL). He is tachycardiac and lethargic. The patient’s physi­cian wants to transfuse him with packed red cells. You suggest:

  1. Transfusion of 1 unit of packed red blood cells over 4 hours.
  2. Transfusion of 20 cc/kg of packed red blood cells.
  3. An initial transfusion of 2 or 3 cc/kg of packed red blood cells over 4 hours.
  4. He does not need transfusion of packed red blood cells; in­stead, iron supplementation only should be initiated.
  5. Transfusion of 1 L of normal saline.

C. Patients with acute hemorrhage may be given red cell trans­fusion as quickly as necessary to maintain cardiovascular stabil­ity. In contrast, patients with severe iron-deficiency anemia or any other long-standing anemia have adapted to the persistently lower intravascular volume. Aggressive administration of fluids or packed red blood cells in such patients could quickly lead to heart failure; therefore, transfusion must start slowly.

A 7-year-old boy presents with a rash on his lower extremities and right knee pain. He has had a low-grade fever, abdominal pain, and has felt tired. Upon physical examination he has a nontoxic appearance and has palpable petechiae on his lower ex­tremities and buttocks. His right knee is edematous, erythema­tous, and warm. He is able to bear weight on his right leg, but the range of motion of his right knee is limited by the edema. The next step in treatment is to:

  1. Begin a course of systemic corticosteroids.
  2. Begin empiric antimicrobial therapy for sepsis.
  3. Obtain a urinalysis and provide supportive care.
  4. Perform aspiration of the synovial fluid in his right knee.
  5. Administer intravenous immunoglobulin.

C. This child has signs and symptoms of-Henoch-Schonlein purpura. HSP is a vasculitis of the small vessels and may have renal, gastrointestinal, joint and dermatologic involvement. Ini­tial therapy consists of hydration and pain control. With renal involvement, urinalysis reveals red blood cells, white blood cells, casts or protein. As gastrointestinal complications include; hemorrhage, obstruction, and intussusception, complaints of abdominal pain requires careful evaluation.