Chief Complaint: 8-year-old girl with excessivethirst, frequent urination, and weight loss.

History: Cindy Mallon, an 8-year-old girl inpreviously good health, has noticed that, in the past month, she isincreasingly thirsty. She gets up several times a night to urinate,and finds herself gulping down glassfuls of water. At the dinnertable, she seems to be eating twice as much as she used to, yet shehas lost 5 pounds in the past month. In the past three days, shehas become nauseated, vomiting on three occasions, prompting avisit to her pediatrician.

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Questions

1. At the doctor's office, blood and urine samples are taken.The following lab results are noted:

blood glucose level = 545 mg/dl blood pH level = 7.23

(normal = 50 - 170 mg/dl) (normal = 7.35 - 7.45)

urine = tested positive for glucose and for acetone /acetoacetate (i.e. ketone bodies) (normally urine is free ofglucose and ketone bodies) Question 1: How will the urinary system attempt torectify Cindy’s decreased blood pH? Be specific. In her mid-forties, Cindy began to show early signs of diabeticnephropathy (kidney disease), consisting of persistent proteinuria,hypertension, and gradually decreasing renal function as measuredby chemical tests. She nonetheless felt fairly healthy over thenext 10 years. At age 55, however, she has noticed becomingincreasingly fatigued upon mild physical exertion and requiringmore sleep than previously. In addition, she has generally feltnauseated most of the time, and in the past two weeks, has vomitedon several occasions. She has increased swelling in her ankles, andis short of breath. She has also become less responsive over thepast day or so. Laboratory tests reveal that her kidney disease isnow progressing at a much faster rate: BUN (blood urea nitrogen) = 56 mg / dl        (normal = 10 - 20 mg /dl) Urinary output = 25 cc / hour                       (normal = 50-60 cc / hour) Cindy is advised by her physician that her kidneys are failing.She is informed about treatment options: hemodialysis vs.continuous ambulatory peritoneal dialysis (CAPD) vs. kidneytransplant. In consultation with her physician, Cindy chooses toundergo hemodialysis. A checkup two weeks after beginning dialysisreveals the BUN has decreased to 35 mg / dl. Although hemodialysisis fairly effective, it is not fool-proof. For example, patientswith chronic renal failure, despite a regular schedule ofhemodialysis, will experience disruptions in calcium and phosphatebalance. Question 2: How might the endocrine system compensatefor the change in blood calcium levels?