Case Presentation - Final Product:
S.M. is a 65 year old Hispanic female with type 2 diabetes mellitus, hypertension, hyperlipidemia, coronary artery disease requiring coronary artery bypass graft surgery in 2006, osteoarthritis and chronic kidney disease stage 3 with a baseline creatinine level over the past 6 months ranging between 1.4 and 1.6 mg/dl. The patient’s most recent serum creatinine as an outpatient was 1.4 mg/dl in October 2010 on a blood test obtained at her primary care physician’s office. Because of the recent cold weather, her joints have been hurting more than usual and she has been taking over-the-counter Advil 200 mg strength 3-4 times per day for the past couple weeks.
This patient presented to her cardiologist last week complaining of frequent episodes (almost daily) of angina (chest pressure similar to the type of pressure she had before requiring bypass surgery in 2006) brought on by walking briskly or doing mildly strenuous activities like climbing stairs. Her cardiologist subsequently recommended a cardiac catheterization test (study utilizing injectible contrast dye to visualize the coronary arteries and bypass grafts looking for blockages). The patient underwent this cardiac catheterization procedure which revealed 2 mild to moderate severity stenoses (blockages) of the bypass grafts but, no lesions that required angioplasty/stents or repeat bypass surgery. The cardiologist recommended solely “medical therapy” of these stenoses with adjustment of the patient’s anti-anginal medications. The patient left the hospital a few hours after this procedure feeling fine.
Three days later, the patient presented to the emergency room complaining of feeling weak, nauseous, and having no appetite. She also noticed that she had been making less urine over the past day and the small amount of urine she made appeared dark and concentrated. On physical examination, blood pressure was 150/90 mmHg, pulse was 84 bpm, weight was 153 lbs (patient normally weighs 145 lbs) and the emergency room physician noted that the patient had “crackles” in the lower portions of her lung exam and 2+ (moderate amount) edema in both ankles. On blood testing, the patient had a serum creatinine of 4.5 mg/dl, BUN of 58 mg/dl and potassium level of 6.1 meq/L.
Normal serum creatinine 0.6-1.2 mg/dl
Normal BUN 7-18 mg/dl
Normal potassium (K) level 3.5-5.4 meq/L
Normal blood pressure <130/80
Questions to think about:
What is this patient’s new problem(s)/diagnosis(es)?
The patient presents a new problem of Acute Renal Failure. The symptoms and signs of this are: weakness, nausea, lack of appetite, less urine production, small amount produced was dark and concentrated, high blood pressure, high pulse, weight gain, and fluid in lungs, edema, high creatinine, high BUN, and a high potassium level.
What are the potential causes of this?
The potential causes of the renal failure include the consumption of NSAIDs (Advil) multiple times a day, and the intravenous contrast dye that can cause temporary acute renal failure. This type of acute renal failure is called "contrast nephropathy." It is usually a temporary type of renal failure—kidney function should improve within days to weeks after the contrast dye administration
Are there preexisting conditions that could have made the patient more susceptible to this new problem? If so, what?
Preexisting conditions that made the patient more likely to acquire renal failure are a history of chronic kidney disease, and nutrient levels in the blood. The most recent blood test revealed that creatinine level was 1.4 (higher than average).
What measures could have been taken to prevent this new problem?
The physician would give the patient IV fluids and a medication called mucomyst to "protect" the kidneys from the effects of the contrast dye used before the cardiac catheterization procedure.
What further testing should be done to confirm this new diagnosis?
1. Urinalysis (urine sample): This procedure involves using a dipstick that has different reagents on it that change to different colors based on the presence of RBCs, WBCs, or protein in the urine. This is done by placing the dipstick in the urine sample. If any of the aforementioned cells were found in the urine, the physician would consider inflammatory kidney disease as the cause of acute renal failure instead of the failure being caused by the medication or procedure.
2. Renal Ultrasound: This procedure would reveal any blockages of urinary flow accounting for acute renal failure. For example, kidney stones in the ureter would greatly decrease urine excretion. The physician would expect this test to be negative.
What can be done to treat this new diagnosis?
Both the medication effect and procedure effect just have to "wear off."
The physician would have to make sure the patient is no longer taking the medication that caused renal failure. The patient would be started on a diuretic like Lasix because of the excess of fluid in her body (presence of fluid in lungs and ankles—edema). The patient would be treated with Kayexelate, a medication that causes diarrhea and reduces blood potassium level through loss of potassium from the G.I. tract. If the diuretic failed to help the patient make more urine, or if the Kayexelate did not bring the potassium level down to normal, the doctor would consider doing acute hemodialysis (blood filtering procedure) using a catheter. Hemodialysis is done by placing a catheter in a large vein (Ex: internal jugular vein or femoral vein) to remove excess fluid from the blood stream and excess potassium from the blood.
