HEME cases

Question 1

1. A 62 yo male with HTN and DM presents for a routine visit and lab review. BP 136/84, HR 74. PE is unremarkable. On CBC his Hgb is 12, Hct 37%, MCV 82. On CMP his creatinine is 1.8, glucose (fasting) 138. Hgb A1c 8%. Urine microalbumin 60 (normal <30). The remainder of his labs are normal. What is the most likely cause of his anemia?

Answer 1

· Anemia of chronic disease; poor renal function from HTN and DM

Question 2

2. A 45 yo female c/o increasingly heavy menstrual periods x 6 months, hot flashes and night sweats. She is fatigued but denies DOE, palpitations or tachycardia. VSS, PE normal. Hgb 10, Hct 32%, MCV 74. What is the next lab test you want to order?

Answer 2

· Iron studies: serum iron, TIBC, ferritin

Question 3

3. A 56 yo male s/p gastric bypass surgery c/o fatigue, numbness/tingling in his hands and feet, and a raw feeling in his mouth. You note glossitis and decreased vibratory sensation on his distal extremities. Hgb 10, Hct 34%, MCV 120. What is the pathophysiology of this condition?

Answer 3

· Vitamin B12 is absorbed in the terminal ileum, attached to intrinsic factor; due to gastric bypass surgery the gut absorption has been damaged/reduced, resulting in macrocytic anemia and ineffective erythropoiesis from vitamin B12 deficiency

Question 4

4. A 22 yo male recently had a viral illness and now c/o fatigue, nausea and jaundice. On exam you note mild jaundice and splenomegaly. Lab results show anemia with low MCV, increased reticulocyte count, and a negative Coombs test; the peripheral smear shows a predominance of spherocytes. The eosin-5-maleimide binding test is positive. What is the pathophysiology of this condition?

Answer 4

· Hereditary spherocytosis (HS) is the most common hemolytic anemia due to a red cell membrane defect. It is a result of heterogeneous alterations in one of six genes (most often the ankyrin gene) that encode for proteins involved in vertical associations that tie the membrane skeleton to the lipid bilayer.

Question 5

5. A 12 yo African American male has one parent with sickle cell trait. What test would you order to determine if the patient is a carrier of this trait as well?

Answer 5

· Hemoglobin electrophoresis

Question 6

6. A 15 yo female c/o heavy menstrual bleeding since menarche at age 12; she also reports easy bruising. She has a family history of bleeding disorder, but she does not know what type. PE is normal. A CBC shows mild microcytic anemia; she is found to have a decrease in von Willebrand factor activity. What is the next step in the management of this patient?

Answer 6

· Refer to Hematology for classification of the type of von Willebrand disease and appropriate treatment

Question 7

7. A 36 yo female presents for a well woman exam; she is asymptomatic without any complaints. On review of her labs, everything appears normal except a mild anemia with a very low MCV. She tells you her family is from Greece. What is the most likely diagnosis?

Answer 7

· Thalassemia, most likely β-thalssemia minor based on ethnic/racial heritage, minor anemia without symptoms

Question 8

8. A 60 year old man presents with thrombophlebitis on his right leg; on further questioning he reports sweating, headache, malaise, nausea and itching after a hot shower. On PE you note the thrombophlebitis of the RLE as well as HSM and facial plethora. CBC shows erythrocytosis and thrombocytosis with Hgb 19. You order a test for JAK2 mutation because you suspect:

Answer 8

· Polycythemia vera

Question 9

9. Hannibal Lecter enjoyed a meal including fava beans and a nice Chianti; if he was lacking a certain enzyme, this would cause headache, nausea, back pain, fever/chills, jaundice and hemoglobinuria. What will cause such a presentation?

Answer 9

· Glucose-6-phosphate dehydrogenase (G6PD) deficiency will cause hemolytic anemia with ingestion of certain foods or medications, including fava beans

Question 10

10. A 78 yo female with colon cancer c/o acute onset of pleuritic chest pain, fever and shortness of breath. On exam she is tachycardic and tachypneic with a fever. She has a positive D-dimer. What is the best diagnostic study to confirm your suspected diagnosis?

Answer 10

· CT angiogram to diagnosis acute pulmonary embolism

Question 11

11. A 14 yo male is brought in for rash and nosebleeds that have been occurring for the past week; he had a viral syndrome 2 weeks ago. On PE you note a petechial rash on his extremities. CBC shows isolated thrombocytopenia. What is the most likely diagnosis?

Answer 11

· Idiopathic (immune) thrombocytopenic purpura (ITP)

Question 12

12. A 55 yo Caucasian male presents with his second DVT in 3 years. After his first DVT he was on warfarin for 9 months. Genetic testing indicates that the patient has the Factor V Leiden mutation. What is the pathophysiology of this condition (how does this mutation cause thrombosis)?

Answer 12

· Factor V is a procoagulant clotting factor that amplifies the production of thrombin, the central enzyme in formation of fibrinogen from fibrin, which leads to clot formation. Factor V Leiden results from a single point mutation in the factor V gene, which leads to a single amino acid change. The factor V Leiden mutation simultaneously increases coagulation by creating two distinct changes in the coagulation cascade: Reduced anticoagulant role of factor V and Enhanced procoagulant role of factor Va. The dual roles of factor V also help to explain why the risk of thrombosis is greater in patients homozygous or pseudohomozygous for factor V Leiden. The plasma of heterozygotes contains factor V Leiden and normal factor V. The normal factor V has APC cofactor activity for the inactivation of factor VIIIa, affording some protection against thrombosis. [from uptodate.com]

Question 13

13. A 24 yo female has had 4 spontaneous miscarriages. She is a generally healthy Hispanic female who does not smoke, take any medications or drugs. Her menstrual periods are heavy but regular. Her father died of an MI at the age of 43. Her PE is unremarkable. Her initial lab evaluation including CBC, CMP, TSH is normal. What is next in the evaluation of this patient?

Answer 13

· She needs to be evaluated for an inherited thrombophilia, including Factor V Leiden, protein C/S deficiency, prothrombin gene mutation, and antithrombin deficiency (she ended up having protein C deficiency, and with appropriate antepartum treatment now has 3 healthy children)

Question 14

14. A 26 yo female PA student goes to Mexico for 1 week after Summer semester. The week prior to her trip she had arthroscopic repair of a torn ACL in her right knee. She takes oral contraceptives (OCP), no other medications. Two days after arriving in Mexico she develops pain and swelling in her right calf. What is the most likely diagnosis?

Answer 14

· Deep venous thrombosis (DVT)

Question 15

15. What is the appropriate management of the above patient?

Answer 15

· Low molecular weight heparin (Lovenox) SQ daily and begin warfarin therapy; discontinue Lovenox when INR reaches 2-3, continue warfarin 6-9 mos with goal INR 2-3. Discontinue OCP indefinitely, consider evaluation for inherited thrombophilia.

Question 16

16. The above patient returns from Mexico and has labs done; her INR is 6 (goal 2-3). She denies active bleeding. How do you manage this?

Answer 16

· Assuming she is no longer on Lovenox (d/c Lovenox immediately if she is still taking it), hold warfarin for 2 days, give an injection of vitamin K today and recheck INR in 2 days. · Please note, this is what I would do; you will find a lot of clinical variability in managing warfarin, and as long as you have close follow up of your patient it will turn out ok!

Question 17

17. A 62 yo female, previously well, c/o fatigue and rash progressively worse over the past several weeks. On PE you note conjunctival pallor, gingival hyperplasia and petechiae on the arms. CBC shows WBC 60,000, Hgb 9, Hct 28%, platelets 40,000. A peripheral smear shows a predominance of immature cells. You refer the patient to Hematology for evaluation and a bone marrow biopsy, because you suspect what diagnosis?

Answer 17

· Acute myeloid leukemia (AML)

Question 18

18. A 52 yo male c/o fatigue, night sweats and anorexia over the past 6 months; he reports weight loss of about 12 pounds in that time. On PE you note splenomegaly, no other abnormalities. CBC shows mild normocytic anemia, normal platelets, WBC 55,000 with increased basophils. He has positive Philadelphia chromosome. What is the diagnosis?

Answer 18

· Chronic myeloid leukemia (CML)

Question 19

19. A 28 yo male c/o painless right neck lymphadenopathy x 2 weeks; he was treated with a course of antibiotic without resolution. CBC shows Hgb 10, Hct 32%, MCV 80, WBC 3,000, platelet count 100,000. He has elevated serum LDH level. What is the next step in the evaluation?

Answer 19

· Excisional biopsy of the lymph node for probably lymphoma

Question 20

20. 70 yo female with hypothyroidism presents for a routine exam. On exam you note bilateral nontender cervical adenopathy. Lab results show TSH 1.5; WBC 17,000 with predominance of lymphocytes, Hgb 11, MCV 80, platelets 150,000. You order flow cytometry of the peripheral blood, which shows clonality of the circulating B lymphocytes. What is the most likely diagnosis?

Answer 20

· Chronic lymphocytic leukemia (CLL)