Thursday 11/10/2005

8:30 AM– 10:30 AM

A 35 year old woman is seen for easy fatigue for many months. She is now 24 weeks pregnant with her 3rd child in 3 years. She does not see any obstetrician and does not take any vitamins. Lately, she has developed a taste for eating ice. She has no other complaint. Family and past history are negative. She does not smoke or drink. Physical examination is positive for pale conjunctiva, mild spooning of nails, and a II/VI systolic murmur at left lower sternal border. Stools are negative for occult blood.

Labs: Complete blood count (CBC) - Hg 7.1 gm/dl, Hct 23%, WBC 5,400/mm3 (differential is normal), platelets 450,000/mm3; Mean Corpuscular volume (MCV) is 74 fl (normal 85-95 fl); Red cell Distribution Width (RDW) is 17.1% (normal 13-15).

QUESTIONS

1. Explain "tasting for eating ice". Spooning of nails.

2. How reliable is physical examination in diagnosing anemia?

3. What is the normal RBC

4. What is the main function of RBC's?

5. First step is to make a distinction between hypo- and hyperproliferative anemia. How will you decide that? What is your understanding of  those terms?

6. How will you recognize reticulocytes in the peripheral smear?

7. How do you count and express reticulocyte count? 

8. How do MCV and RDW help you in the diagnostic work-up of anemia? Do the other indices-Mean Corpuscular Hemoglobin (MCH) and Mean Corpuscular Hemoglobin Concentration (MCHC)-add anything?

Let us return to our case. She has MCV of 74 fl (normal 85-95 fl). Let us evaluate her peripheral smear. 

She has microcytic hypochromic anemia.

9. What is the differential for microcytic hypochromic anemia.

10. Does microcytic anemia represents a maturation defect or abnormal hemoglobin synthesis?

11. How would you proceed to differentiate between the different possibilities for  microcytic anemia?

12. What further tests would you like to do in this patient to confirm iron deficiency? 

13. Calculate her iron saturation? How useful is iron saturation in the diagnosis of anemia's?

14. What is ferritin? How do you interpret low and high ferritin values?

15. If this patient was African-American, would you want to obtain a hemoglobin electrophoresis?

16. Should one do a bone marrow test in this patient? If one did , what would you expect to see?

17. Could she have 'anemia of chronic disorder'? What are the known mechanisms of anemia of chronic disorder?

18. Your intern wants you to order a B12 and folate level also, for sake of completeness. Is that justifiable?

Now that we have confirmed that this patient has iron deficiency anemia, let us understand few basics.

19. What tissues /cells require Iron for normal development?

20. What are the normal resource for iron in diet?

21. What is the daily requirement of iron for a normal adult? Is it different for females or pregnant women?

22. This patient's old records indicate that she did not have a murmur in the past. Should one obtain an echocardiogram to rule out valvular heart disease?

23. What are the common causes of iron deficiency anemia? Children, Young adult, Older adult. Males, Females.

24. What are the clinical sequelae to iron deficiency anemia?

25. What is your therapeutic strategy for treatment of iron deficiency anemia?

26. What treatment would you prescribe for this patient?  How soon should you expect a response?

27. How long will you treat her with iron supplement and why?

28. In which part of GI tract is iron absorbed? What else is necessary for iron absorption?

29. Are there any problems associated with iron therapy?

30. Is there a role for Blood transfusion?