Question

A 52-year-old man with a history of AIDS, hypertension, diabetes mellitus, and alcohol abuse was found unconscious in his home by his roommate. In the ER, he was hypotensive (103/60 mm Hg), febrile (101º F), and unresponsive. Computed tomography scan of the abdomen showed cholecystitis and gallstones.

The patient was diagnosed with acute renal failure. He was administered intravenous fluids; BUN fell to 68 mg/dL and creatinine fell to 2.2 mg/dL. The patient’s blood culture report was positive for E. coli. He was treated with tobramycin and cefepime. The patient continued to deteriorate and died 5 days after admission. Cause of death was multiorgan failure secondary to AIDS, sepsis, and alcoholic cirrhosis.

Drugs of Abuse        Negative

Serum ethanol        84 mg/dL

CK                3,308 U/L (24-204)

CK-MB            15 ng/mL (0-7.5)

Troponin T            <0.01 ng/mL (0-0.4)

pH                7.50

pCO2            27 mm Hg

Total CO2            15 mmol/L

Urinalysis:

Hemoglobin                Positive

WBC                        4 HPF (0-4)

RBC                        2 HPF (0-4)    BUN                        71 mg/dL (8-21)

Creatinine                    4.1 mg/dL (0.9-1.5)

Alkaline phosphatase            443 U/L (45-122)

Aspartate aminotransferase        305 U/L (9-45)

Alanine aminotransferase        78 U/L (8-63)

G-glutamyl transpeptidase        724 U/L (11-50)

Total bilirubin                 2.7 mg/dL (0.2-1.0)

Direct bilirubin                2.4 mg/dL (0-0.2)

1. What is significance of the patient’s elevated CK? Explain why the physician ordered a CK-MB and troponin level. What can you conclude about the patient’s cardiac level?
2. what is the cause of his acute renal failure?

3. What is the significance of the patients large urine hemoglobin?

4. how would you interpret this patient's liver function tests considering his clinical history?

           

Answer 1

1. CPK MB is elevated in myocardial infarction (early detection) and muscular dystrophy reference unit is 10-50 IU.

CPK has 3 isoenzymes CPK1, CPK2, (subunit MB) and tissue of origin is heart, CPK3. In healthy individuals CPK2 is almost undetectable in serum with less than 2% of total CPK. After MI within first 6-18 hours CPK2 increases in the serum to as high as 20%. CPK2 is not elevated in skeletal muscle disorders so it the earliest reliable indicator of MI or that the patient has suffered an attack.

Troponin and tropomysin tests are done in preference to CPK. Troponin is the biomarker of choice for detection of MI. It is a protein released due to injury to myocardium due to ischaemia. Expression of Troponin is more specific and sensitive than CPK. Troponin levels are 0.00 to 0.04 units. Here the CPK MB (5-25 IU/l) and troponin levels are within normal limits hence the patient did not suffer from MI.

2 since the patient's blood culture shows presecence of E. Coli and also he died of sepsis.. The acute renal failure could possible due to septic shock which would have resulted in acute tubular necrosis leading to renal failure.

3 - e coli infections of urethra can lead to hemoglobinuria. The patient could have developed polynephritis commonly caused by E. Coli or haemorrhagic cystitis.

4- since the patient is a case of alcohol abuse and suffered from liver cirrhosis his serum AST, SGPT and SGOT must be elevated.

SGOT - ( aspartate transaminase) activity is increased In serum MI also in liver diseases. SGPT - (alanine transaminase) is elevated in acute hepatitis, jaundice and cirrhosis.

Alkaline phosphate levels elevated indicates hepatitis. Since the the liver enzymes where elevated much more than normal range also the patient is an alcoholic .. The patient suffered from liver cirrhosis and hepatitis..