Chief Complaint: 8-year-old girl with excessive thirst, frequent urination, and

Question

Chief Complaint: 8-year-old girl with excessive thirst, frequent urination, and weight loss. History: Cindy Mallon, an 8-year-old girl in previously good health, has noticed that, in the past month, she is increasingly thirsty. She gets up several times a night to urinate, and finds herself gulping down glassfulls of water. At the dinner table, she seems to be eating twice as much as she used to, yet she has lost 5 pounds in the past month. In the past three days, she has become nauseated, vomiting on three occasions, prompting a visit to her pediatrician. 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 urine = tested positive for glucose and for acetone / acetoacetate,

A-5. Explain why Cindy is urinating so frequently?

6. How is Cindy's condition like that of starvation? Address the role of glucagon in your answer. Following her visit to the pediatrician, Cindy undergoes a diabetic care training program, learning how to self-inject insulin subcutaneously and check her blood-glucose level at home with chemstrips. In addition, she learns the importance of carrying candy and glucagon with her at all times as well as eating the right amounts of food at the right times each day.

7. What dangers confront Cindy as she gives herself insulin artificially on a daily basis?

8. Why must she carry candy and glucagon with her at all times?

9. Cindy is started on the following schedule of insulin dosing: morning dose = 8 units of NPH insulin and 4 units of regular insulin supper dose = 4 units of regular insulin bedtime dose = 5 units of NPH insulin total dose per day = 21 units. Three days later, she returns to the doctor's office for a review of her blood-glucose readings and a measurement of her fasting blood-glucose level, which is found to be 95 mg/dl. Most of her glucose readings during the day have been in the low- to mid-100 range. Her glucose levels before supper, however, are in the upper 200s.

10. How might you adjust Cindy's insulin-dosing schedule to bring her pre-supper glucose levels down? Cindy returns to her pediatrician three months later for a re-check, and is found to have a glycosylated hemoglobin level (Hb A1C) of 9.5%.

11. What is glycolsylated hemoglobin? What is the normal range for glycosylated hemoglobin?

12. What does Cindy's Hb A1C level indicate that a one-time direct measurement of blood glucose doesn't indicate?

Explanation / Answer

A-5. Due to the elevated levels of blood-glucose in Cindy the rate at which glucose filters out of blood is at an increased rate. Therefore during reabsorption the blood stream gets flooded by glucose and saturation occurs in the active transport pumps. Due to this saturation no more glucose can be reabsorbed and hence it remains in the renal tubules only. Then the water present in bloodstream gets drawn to the renal tubules by the process of osmosis. Due to this osmotic diuresis Cindy urinates frequently and gets the urge to drink so many glasses of water.
6. When body is starved body tries to compensate by ensuring that body has enough fuel and hence energy rich nutrients are still present in the bloodstream. To achieve this blood glucose levels are increased. Similarly in Cindy’s condition blood glucose levels are increased but due to low insulin level the organs are not able to take up the nutrients and utilize them. So these tissues are also starving. Hence in both the conditions insulin activity is outweighed by glucagon activity.
7. Cindy may not be able to correctly estimate the required insulin level as she is taking it through injection. There is the danger of under or over estimation of needed insulin level. She has the danger of diabetic ketoacidosis if by mistake she underestimates the insulin required as the glucose levels in blood may increase above the normal level.
8. In case Cindy over-estimates the insulin required in her blood then the level of glucose may decrease below normal level and cause hypoglycemia. This may further lead to insulin shock and coma. Hence, should carry candy and glucagon with her so that she can quickly take them in case her blood glucose gets low
9. This is not a question but information for the next set of questions.
10. For adjusting her dosing schedule the pre-supper blood glucose level is the best option. As before supper she is hyperglycemic hence she will need to make an increase in her morning dosage of NPH. Another solution would be to take insulin injection regularly before lunch.
11. When hexose is non-enzymatically attached to the hemoglobin’s beta chain then we get glycosylated hemoglobin. The normal percentage would be 6% of the total hemoglobin.
12. The elevation in Hb A1C point that with passing time Cindy’s blood has elevated glucose levels. So for around 3 months control of blood glucose can be estimated by this. Whereas direct measurement of blood glucose level will only point towards the level that is present at that point of time in blood.

Related Questions

Navigate

• Browse (All)
• Browse C
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.