Case Studies

HEMATOLOGY CASE STUDY

A 58-year-old African American woman presents to the ER with complaints of progressive fatigue and weakness for the past 6 months. She is short of breath after walking several blocks. On review of the systems, she mentions mild diarrhea. She has noted intermittent numbness and tingling of her lower extremities and a loss of balance while walking. She denies other neurological or cardiac symptoms and has no history of black or bloody stools or other blood loss. On physical examination, she has tachycardia (110 bpm); other vital signs are within normal limits. Head and neck examination is notable for pale conjunctivas and a beefy red tongue with loss of papillae. Cardiac examination shows a rapid regular rhythm with a systolic murmur at the left sternal border. Lung, abdominal, and rectal exams are normal. Neurologic examination reveals decreased sensation to light touch and vibration in the lower extremities. The hematologist on call is asked to see this patient because of a low hematocrit and many macrocytic erythrocytes noted on the CBC differential.

QUESTIONS

1. a) This patient is probably suffering from what type of vitamin deficiency?

b) How/why does this result in anemia? (Be specific)

2. a) Besides macrocytes, what other findings are typical in blood smear with this type of anemia?

b) What other blood tests may be ordered and what are the anticipated results?

3. a) Workup reveals pernicious anemia. What is the pathogenesis of this disease?

b) What is the evidence to support an autoimmune origin?

4. Explain the significance of each of the following (what is it? what does it imply?)

a. tachycardia

b. heart murmur

c. black or bloody stool

5. What is the pathophysiologic mechanism of this woman’s symptoms of tachycardia, paresthesia, and impaired proprioception?

HEMATOLOGY CASE STUDY 2

Ms. Thomas, a 35-year-old female, was brought to the ER complaining of excessive bleeding following a therapeutic abortion performed 5 days earlier. She appeared to be in acute distress, with cold, mottled fingers and toes along with severe vaginal bleeding and evidence of nasal and oral bleeding. She was examined and taken to the OR where a large segment of retained placenta was removed. Lab tests included abnormal coagulation studies, especially partial thromboplastin times (67 seconds for a PTT) and a decreased fibrinogen count (105 mg/dl). An increased titer of fibrin degradation products (35 ug/ml) was found.

QUESTIONS

1. What does DIC stand for?

2. What type of disorder is it? Explain how this disorder is both a bleeding and a clotting disorder.

3. Describe the pathophysiology of this disorder.

4. Explain the reasons for the symptoms she is exhibiting.

5. Research the partial thromboplastin time, fibrinogen count, and fibrin degradation products – what is a normal value (range) for each, what does each lab test analyze, and speculate as to what might cause these lab values to be abnormal.

6. What risk factors are present in this patient for developing DIC?

7. There is acute and chronic DIC – which do you think occurred here. Justify your answer.

8. Why was the surgical procedure performed on a critically ill patient? What other treatment measures might be effective?

ENDOCRINE SYSTEM CASE

PART 1: HISTORY

A 27-year-old woman presents with depression, insomnia, increased facial fullness and recent increase in facial hair. She had also had an episode of depression and acute psychosis following uncomplicated delivery of normal baby boy 9 months previously. Her menses have been irregular since their resumption after the birth (she is not breast-feeding).

PHYSICAL EXAM

The heart rate was 90 beats per minute and the blood pressure was 146/110. Her face was puffy with an increase in facial hair and ruddy complexion. There was no truncal obesity, peripheral wasting, or striae.

ROUTINE LABS

Serum electrolytes:

K: 4.1 mEq/L

Na: 142 mEq/L

Cl: 101 mEq/L

White cell count: 6,700 cells/mm3

H&H: 14 g/dL; 41%

QUESTIONS

1. What parameters or clinical findings are abnormal? Identify whether they are high or low?

2. What are “striae” and what would they indicate?

3. What is/are the most probable diagnosis so far? Explain/Justify your answer.

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PART 2: PROBABLE DIAGNOSIS - ADRENAL DISORDER

DISCUSSION

There's not a lot of specific information to go on in this presentation. The increase in facial hair (hirsutism) might suggest increased androgens, and the depression and puffy face could fit into Cushing's syndrome. She is significantly hypertensive, which could be compatible with mineralocorticoid excess. The combination of increased androgens, cortisol, and mineralocorticoids, if present, would suggest increased adrenal stimulation by ACTH because all three major pathways of adrenal output would be hyperactive.

However, the serum electrolytes, which often show a hypokalemic alkalosis in mineralocorticoid excess, aren't helpful in this case. Also, the physical signs of Cushing's syndrome (and the hyperpigmentation that may be present in Cushing's disease) are minimally present, if at all. This could indicate a relatively early Cushing's, or another etiology for the patient's problems. Other causes for hypertension in a young woman (e.g. renovascular disease or pheochromocytoma) should also be considered.

Remember that depression and confusion with a puffy face can also be compatible with hypothyroidism (though a heart rate of 90 would be unusual in that setting), and depression in general following childbirth is not uncommon.

The bottom line is we really need more information before narrowing the differential too much.

QUESTION

4. What laboratory tests would you order to evaluate this patient? Explain what you are looking for in the lab results?

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PART 3: LABORATORY STUDIES

Because the symptoms in this case are fairly nonspecific, tests were carried out to evaluate pituitary, thyroid, and adrenal status.

Patient Reference

TSH (S) 3.2 uU/ml 0.7 - 7.0

T3, Total (S) 160 ng/dl 75 - 200

T4, Total (S) 6.2 µg/dl 4.6 - 12

Prolactin (S) 14 ng/ml Nonpreg. <20

LH, mid-follicular (S) 6 mU/ml 5 - 20

FSH, mid-follicular (S) 10 mU/ml 2.6 - 16

Cortisol

24:00 (S) 37 ug/dl <5

08:00 (S) 49 ug/dl 5 - 25

ACTH, 08:00 (P) 135 pg/ml <100

Cortisol (24 hr urine) 160 ug 20 - 90

17-OH-Corticosteroids (24 hr urine) 11.9 mg 3 - 8

17-Ketosteroids (24 hr urine) 18.8 mg 5 - 15

(S = serum specimen)

QUESTIONS

5. How would you interpret these results?

6. Your partner has suggested you order the following: Dexamethasone suppression testing. Research what this is for and why it is being suggested. What if this test is abnormal – what then would be indicated in this patient?