Pick any two diseases that require diagnostic tests to identify them from the body system. Use of the body systems: cardiovascular, respiratory, renal, hepatobiliary, lymphatic, reproductive or nervous systems. For each of the diseases, explain:

• Why is a particular test recommended?
• How does the test work?
• What information is obtained from the diagnostic test regarding the disease?
• Does the diagnosis need confirmation with another diagnostic test?

The hepatobiliary system

Test for hepatobiliaryoften starts with a pain that a person may be experiencing in the upper right side of their stomach or they may be having digestive problems and feel as if their food isn't digesting properly and bring this to their doctor's attention. Or, the doctor could find an abnormal sound and ask a series of questions while examining the patient during a routine check-up.

The doctor then prepares a series of diagnostic testing. The hepatobiliary system consists of the liver, the pancreas, bile ducts and gallbladder. One such organ that can sometimes become diseased is the gallbladder.(St Peter's Hospital, n.d.) It is an organ of the hepatobiliary system that can sometimes develop gall stones or gallbladder cancer, bile duct cancer (cholangiocarcinoma) leaks (of bile, caused from trauma and surgery) and stricture (a narrowing of the bile duct that moves bile from the liver to the small intestine.

To determine which of these conditions are affecting the diseased gallbladder, there are a few diagnostic tests that a person would have to subscribe to or have done. One such test to start with to check for gallstones is a CT scan to gather pictures of your gallbladder to look for signs of gallstones. To check for gallstones in the bile ducts to determine if a blockage has occurred from a gallstone stone is possibly a hepatobiliary iminodiacetic acid (HIDA) scan in this scan the radioactive chemical or tracer (dye) is injected into a view in your arm, or a magnetic resonance imaging (MRI) or endoscopic retrograde cholangiopancreatography (ERCP). Gallstones discovered using ERCP can be removed during the procedure. A dye is used along with the test to highlight the images so that your doctor can determine if a gallstone is present or other disease is present. (Merck Manual, 2016)

Other tests along with the above test will also include blood tests to see if any infections or other complications are present. These tests can result in the finding of any blockages in the bile ducts. During a gallbladder scan this radioactive tracer (dye) which is injected into the arm can move through the bloodstream and to the bile that flows through the ducts to the gallbladder. The gallbladder releases the tracer into the small intestine. A camera (gamma) (Merck Manual, 2016) takes pictures of the tracer as it moves through the liver, bile ducts, gallbladder and small intestine. (Merck Manual, 2016

This helps to determine the cause of pain, check the function of the gallbladder in the right side of the stomach. An ultrasound may be done before a gallbladder scan to help find structural problems in the gallbladder. The ultrasound is the best diagnostic test that can detect any abnormality that may exist within the hepatobiliary system. A gallbladder scan determine the cause of jaundice if present, find blockage of the bile ducts and look for leakage of bile which is an  after surgery or from an injury which is known as 'strictures'.

Further test may be needed if after during the initial ultrasound. Blood test along with the CT, MRI or scintigraphy may be given to substantiate a diagnosis. The Ultrasonography is the primarydiagnostic test in gallbladder disease because of its high accuracy. (Merck Manual, 2016) Blood test along with the ultrasound test would substantiate that the organ is diseased.

The Renal System

The renal system consistsof the kidneys, ureters, bladder and urethra. (National Kidney Foundation, 2016) This is the urinary system of all the organs involved in the formation and release of urine. What would happen if a kidney became diseased? Waste in your body would build up to high levels in your blood and make you ill. From this you may develop complications such as high blood pressure, anemia, weak bones and nerve damage among other illnesses.

Tests are often given for the renal system to measure kidney function and detect abnormalities  during a routine checkup unless the patient comes in with a complaint. This blood test includes measuring the creatinine (waste)removal levels. A creatinine level of more than 1.2 for women and 1.4 for men may be an early sign that the kidneys are not working properly.(National Kidney Foundation, 2016) So if the creatinine in the blood raises this may indicate that there is a kidney disease in progress.

Another blood test is that of the glomerular filtration rate (GFR). This test measure how well the kidneys are removing wastes and excess fluid from the blood. A blood test will also include the blood urea nitrogen (BUN).This test measures the breakdown of protein in the foods you eat. A normal BUN level is between 7 and 20. (National Kidney Foundation, 2016) As kidney function decreases the BUN level raises.

Imaging tests for renal would occur if the blood test would suggest that there is something wrong with the kidney or renal system. An ultrasound (sound waves) will get a picture of the kidney which checks further for abnormalities in size or position of the kidneys or obstructions such as stones or tumors.

The CT scan is another imaging technique that uses the contrast dye to get a picture of the kidneys. This may also be able to be used to look for structural abnormalities and the presence of obstructions.

Kidney biopsy would to identify a specific disease process and determine whether it will respond to a particular type of treatment. It will also evaluate the amount of damage that has occurred in the kidney.(National Kidney Foundation, 2016) The most common of tests is the urine tests which includes the urinalysis, urine protein, and microalbuminuria and creatinine clearance.

If initially the urine test and blood test show abnormal signs, then the MRI's or CT's would have to be taken to have a conclusive finding. These tests would show a detailed image of exactly what is going on and where the infection and or disease are within the organ itself.

Reference

Merck Manual Professional Version, (2016)  Imaging Tests of the Liver and Gallbladder, Retrieved April 9, 2016 from http://www.merckmanuals.com/professional/hepatic-and-biliary-disorders/testing-for-hepatic-and-biliary-disorders/imaging-te

National Kidney Foundation, (2016) Tests to Measure Kidney Function, Damage And Detect Abnormalities, Retrieved April 9, 2016 from https://www.kidney.org/atoz/content/kidneytests