Question

What is urinanalysis? Explain the basis for the presence of:

                a) ketone bodies in the urine of an anorexia nervosa patient.

                b) glucose in the urine

                c) hCG in urine

Answer 1

Answer

Urinanalysis is the test that assess the the concentration of the contents in the urine in order to detect disorders. infections and other physiological imbalances.  

a) Ketone bodies in the urine of an anorexia nervosa patient

• In fasting state, the blood glucose levels are depleted.
• In order to gain energy, liver initiated gluconeogenesis - production of glucose from lipids and proteins.
• Lipolysis (breakdown of lipid) into fatty acids ocurs. when fatty acids are brokendown to glucose, ketone bodies are formed.
• Prolonged fasting, such as in case of anorexia nervous (a person undergoes starvation) leads to build up of ketone bodies in blood that appears in the urine.

b) Glucose in the urine

• Normally, all the filtered glucose is reabsorbed by the cells in proximal convoluted tubule.
• When blood glucose levels are high, such as in case of diabetes mellitus (lack of insulin prevents uptake of glucose by the liver and muscle cells) the levels of glucose in nephron exceeds its transport maximum.
• The transport maximum for glucose in nephron tubule is 375 mg/min.
• Excess glucose cannot be reabsorbed and is excreted in the urine.

c) hCG in urine

• After fertilization of male and female gametes, the zygote implants into the endometrium of the uterus.
• The placenta releases human chorionic gonadotropin (hCG) in the early pregnancy to stimulate production of progesterone by corpus luteum.
• hCG circulates in the blood and is excreted in urine.
• The appearance of hCG in urine can be used as a test to detect preganancy.