MHD I SESSION X. Renal Disease

Transcription

1 MHD I, Session X, Student Copy Page 1 CASE-BASED SMALL GROUP DISCUSSION MHD I SESSION X Renal Disease Monday, November 11, 2013

2 MHD I, Session X, Student Copy Page 2 Case #1 Cc: I have had weeks of diarrhea The patient is a 35 year-old women with AIDS brought to the emergency department with a chief complaint of diarrhea and dizziness. She has averaged 6-7 loose brown stools per day for the past several weeks. She denies having had blood in her stool or melena. She denies nausea or vomiting. Her appetite is poor. Her friend got worried when the patient fell in her apartment because she was dizzy and brought her to the ED The patient is not compliant with her medications. On physical exam the patient is a well-developed, thin female in moderate distress. Vital signs- (supine) blood pressure 100/60, pulse 100 and (standing) blood pressure 80/40, pulse 125, respirations 18 and she was febrile. HEENT exam was normal. Cardiac exam demonstrated an S1 and S2 without S3, S4 or murmur. Lungs were clear to auscultation and percussion. The abdomen was supple and minimally tender to palpation. Bowel sounds were hyperactive. Stool was guiac negative. Extremities were without cyanosis, clubbing or edema. Neurological exam was normal. Laboratory Data BASIC METABOLIC PNL Sodium 136 [ ] mmol/l Potassium 3.4 [ ] mmol/l Chloride 112 [98-108] mmol/l Total CO 2 14 [23-27] mmol/l BUN 42 [7-22] mg/dl Creatinine 1.6 [ ] mg/dl Glucose 105 [70-100] mg/dl ARTERIAL BLD GAS ph 7.35 [ ] pco2 27 [32-46] mmhg po2 90 [74-108] mmhg HCO3 14 [21-29] mm/l BE 3 mm/l STUDY QUESTIONS 1. Calculate the anion gap. 2. What is the primary acid-base abnormality?

3 MHD I, Session X, Student Copy Page 3 3. What is the predicted compensatory response for this acid-based abnormality? Is this a simple or mixed disorder? 4. Formulate a differential diagnosis for conditions which may cause the acid-base disorder present in this patient. What is the etiology in this patient? 5. What are the physiologic mechanisms responsible for the generation of this disturbance? 6. What is your approach to managing this patient?

4 MHD I, Session X, Student Copy Page 4 Case #2 Cc: My husband has been sick for several days and he is worse today The patient is a 35 year-old man with a history of diabetes mellitus, type 1. For the past several days he has complained of malaise, nausea, anorexia, low grade fevers, and muscle aches. His 3 year old daughter stayed home from day care a few days ago because of fever and sore throat. The patient ate very little for dinner the evening before. His wife believes that he may have skipped his insulin the night before as well as this morning. His wife brought him to the emergency room stating that he has become increasingly lethargic. His medications include glargine insulin 16 units before bed and lispro insulin 6 units with meals. He does not smoke and does not drink alcohol. On physical exam the patient is a well-developed, thin male appearing his stated age. Blood pressure 101/62, pulse 102, respirations 28. He was afebrile. HEENT exam was remarkable for mild pharyngeal erythema without exudates. His mucous membranes were dry. Cardiac exam demonstrated an S1, S2 without S3, S4 or murmur. Pulmonary auscultation and percussion were within normal limits. There was mild diffuse tenderness on abdominal exam without rebound or guarding. Extremities were without abnormality. Laboratory Data Basic Metabolic Panel Sodium mmol/l Potassium mmol/l Chloride mmol/l Total CO mmol/l BUN mg/dl Creatinine mg/dl Glucose mg/dl ARTERIAL BLD GAS ph 7.30 [ ] pco2 22 [32-46] mmhg po2 108 [74-108] mmhg HCO3 10 [21-29] mm/l Study Questions 1. Calculate the anion gap. 2. What is the primary acid-base abnormality?

5 MHD I, Session X, Student Copy Page 5 3. What is the predicted compensatory mechanism and response for this acid-based disorder? Is this a simple or mixed disorder? 4. What is the relationship of the bicarbonate and the anion gap? 5. Formulate a differential diagnosis for the conditions which may cause the acid-base disturbance present in this patient. Additional Laboratory Data Ketone Bodies 320 [NEG] mg/dl b-hydroxybutyrate 3.8 [ ] mmol/l 6. What is the etiology of the acid-base disturbance in this patient. Support your answer. How does the above laboratory data help in determining the etiology? 7. What are the physiologic mechanisms responsible for the generation of this disturbance? 8. Discuss your approach to management of the acid-base disorder of this patient.

6 MHD I, Session X, Student Copy Page 6 Case #3 Cc: puffiness and swelling for at least 2 weeks The patient is a 46 year old man who presents to his physician with a concern about swelling over the past several weeks. He and his wife notice that when he wakes up he has a lot of puffiness around his eyes. As the day goes on his feet and ankles begin to swell to the point where he unties his shoes while sitting at his desk at work. His hands are also beginning to feel tight from the swelling. He has no shortness of breath, orthopnea or paroxysmal nocturnal dyspnea. His diet has not changed. He has no chronic medical problems and has had no surgeries. He takes acetaminophen as needed for occasional headaches and no other prescribed or over the counter medications. He has one older brother who has had problems with substance abuse. On physical exam he appears well-nourished. Blood pressure 140/88; pulse 72; respiratory rate 12; temperature F. He has minimal periorbital edema without associated erythema. His lungs are clear to auscultation and percussion bilaterally. On cardiac auscultation S1 and S2 are normal without murmurs, rubs, or gallops. There are no abdominal masses, no abdominal tenderness and no hepatosplenomegaly. Ascites is not appreciated. There is bilateral pitting lower extremity edema to above the knee. There are no skin rashes. There is no cervical, axillary, or inguinal lymphadenopathy. Laboratory Data UA w/micro Color Yellow [YELLOW] ph 6.0 [ ] Spec Gravity [ ] Protein 4+ [NEG] Blood None [NEG] Glucose NEG [NEG] Ketones NEG [NEG] Bilirubin NEG [NEG] Urobilinogen 0.2 [ ] eu/dl NITRATE NEG [NEG] LEUKOCYTES NEG [NEG] RBC 0-2 [0-2] /hpf WBC 0-2 [0-5] /hpf Complete Metabolic Panel Reference Range Sodium mmol/l Potassium mmol/l Chloride mmol/l CO mmol/l BUN mg/dl Creatinine mg/dl Glucose mg/dl Calcium mg/dl Albumin gm/dl Bilirubin, Total mg/dl Alkaline Phosphatase iu/l

7 AST (SGOT) iu/l ALT (SGPT) iu/l Protein, Total gm/dl MHD I, Session X, Student Copy Page 7 CBC RBC 4.43 [ ] m/ul Hgb 13.6 [ ] gm/dl Hct 40.8 [ ] % MCV 89 [85-95] fl MCH 29.2 [ ] pg MCHC 32.7 [ ] gm/dl RDW 14.3 [ ] % Plt Count 325 [ ] k/ul 1. Develop a problem list. The physician reviews the above laboratory data and schedules a follow-up visit in 3 days. The patient feels the same. His blood pressure reading is 146/88. Physical exam is otherwise unchanged. The physician orders additional laboratory tests. Cholesterol 465 <200 desirable mg/dl Protein Urine, random mg/dl Creatinine Urine, random 92.2 mg/dl 2. What is the estimated protein excretion per day?

8 MHD I, Session X, Student Copy Page 8 3. Based on the given data, what is the diagnosis (syndrome)? What is the pathogenesis of the proteinuria? 4. What are the primary glomerular diseases that cause this syndrome? What are systemic diseases that can cause this syndrome? The patient has additional studies done, including serum ANA and complement levels, which are unrevealing as to the cause of his proteinuria. The patient consents to a kidney biopsy. 5. Is the kidney biopsy indicated? Why or why not? A right kidney needle biopsy is performed under ultrasound guidance. There are no complications. The biopsy is reviewed with the pathologist. On light microscopy H&E and PAS stains, the glomeruli are normal (4 glomeruli were present in the biopsied tissue). Cells of the proximal tubules show lipid droplet accumulation. Immunofluorescence staining shows no immune deposits. Under electron microscopy the glomerular basement membrane (GBM) is normal and there are no electron dense deposits. There is diffuse effacement of the foot processes of the visceral epithelial cells.

9 MHD I, Session X, Student Copy Page 9 6. What is the diagnosis? 7. Discuss the epidemiology of this disease. 8. Is there therapy for this disease? What is this patient s prognosis? 9. Review Case Images - Renal Set 1 Case #4 Unknown Students will be provided case data when the session meets. *****