Question

A Day at the Beach - Case Study on Lipid Metabolism
By Justin Hines, Lafayette College, and Marcy Osgood, University of New Mexico

Jessie knew she was late for the family reunion, probably too late for the big picnic lunch at Forest Lake Beach, but too early for the barbecue dinner. “Too bad,” she thought, because she had skipped breakfast, trying to beat the traffic as she left the city. She hoped there would be some leftovers, because she was beginning to get that slightly dizzy feeling, which meant she was pushing her limits. To Jessie's chagrin, there were no leftovers. However, the whole family was sitting and talking on the beach, playing Frisbee golf, and throwing a football. Some of the younger cousins were having swimming contests from a floating platform at the edge of the swimming area. Jessie watched the kids swim and smiled sadly. She had been a competitive swimmer as a teenager and she still missed it. As she watched the group of splashing children, Jessie began to think that something was wrong. One little boy was off to the right, away from all the others. She put her hand up to shade her eyes from the sun and squinted.

The boy was in trouble! He was throwing his arms around randomly, and thrashing the water into a froth. None of the other children were close enough to notice, and there did not seem to be any other adults near enough to raise the alarm. Without any further thought, Jessie ran into the lake. After the first few lunges through the water, she dove shallowly and began swimming towards the now sinking child. Her muscle memory kicked in and her strokes became fast, efficient, and powerful. With each stroke, she raised her head enough to keep the boy's small head in sight. She was making progress, but he was going down quickly.

Jessie pushed harder and picked up speed, but she saw him sinking despite his frenzied paddling. Jessie took a breath and dove. She grabbed the boy's board shorts and kicked hard back towards the surface. She used a one‑sided stroke, which allowed her to keep his head above the water. She swam towards the beach, which seemed to be disappearing into a haze. Jessie felt exhausted, but she kept swimming, breathing in short gasps. Her vision narrowed, and she barely felt the sand beneath her knees as she reached the shallow water. As the little boy was taken from her arms, Jessie lost consciousness.

Jessie awoke in the hospital emergency room, weak and confused. She tried to sit up, but her arms and legs felt heavy, completely without strength. She was dizzy, disoriented, and exhausted. A gray‑haired woman in a short white lab coat came into view, as well as a younger person dressed in scrubs.

“Hello, Jessie. Glad to see you’re finally awake. You were out for a pretty long time. I understand you are a hero! Can you tell me what happened to make you faint? Did you hit your head or swallow too much water? Everyone says that you are a really good swimmer, and no one knows why you fainted.”

Jessie took a deep and unsteady breath. “I haven’t tried to swim that hard since I had a head injury five years ago,” she said. When the doctor asked Jessie if anything like this had happened to her before, she looked sheepish and said, “Yes.” She recalled similar episodes when she had pushed herself too hard.

You are shadowing the emergency room physician, who tasks you with identifying the specific cause of Jessie’s fainting episode.

Initial investigation results

The attending physician evaluates Jessie and determines that she is a young, adult female, with a slim athletic build and no visible injuries.

Fecal analysis shows no blood or intestinal parasites in the stool, and the fat levels are normal.

The physician asks Jessie about her diet as she looks for signs of a neurological problem. Jessie's cognitive function appears to be normal. She reports being a strict vegan for many years, but she claims to eat a large amount of protein from plant sources. She also reports eating a high‑calorie diet, and she occasionally consumes a moderate amount of alcohol. She has never smoked or used illegal drugs, and she does not recall eating anything unusual recently. In fact, she had not eaten anything on the day of the fainting episode because she had been in a rush to get to the lake.

You ask Jessie if she has ever been diagnosed as diabetic or borderline diabetic and whether she has had any trouble controlling her blood sugar levels in the past. She says, "I really don't know."

When asked about her past medical history, Jessie explains that she was on the verge of gaining a swimming scholarship to college when she injured her head in a rock climbing accident. Her head injury led to epileptic seizures, which are now well controlled with an anticonvulsant medication. Swimming was one of the activities she gave up because she feared having a seizure in the water. Since the accident, her endurance has diminished, which she attributed to no longer working out regularly. She sighs and says longingly, “I don’t swim anymore or really do much of anything in terms of hard exercise. I'm just miserably out of shape, I guess.”

You ask whether Jessie has had a blood test to look at her lipid profile recently, and she indicates that she has not had a full physical or bloodwork since she was discharged from the hospital five years ago.

Which blood measurement would be the most helpful in furthering this investigation?

Note: This question will not be graded as long as you answer it.

  

arterial blood pH

   

common electrolytes

   

common lipids

   

lactate and pyruvate

   

oxygen and carbon dioxide

   

total ammonia

Answer 1

ANSWER :-

1. First of all I would like to mention a few points regarding Jessie. She doesnt have any addiction towards drugs although she consumes alcohol occassionally. She is a vegan and consumes more calories and is on a low-fat diet. She consumes a lot of protein rich diet. She had met with an accident during which she developed epileptic seizures which leads to confusion, changes with eye sight, dizziness, etc. She has an athletic body as mentioned above and hence due to the consumption of a low fat diet the test for Lipid profile may not provide a significant help in evaluating the condition.
2. The next point that I would like to introduce is that she takes anticinvulsant which is an anti-epileptic drug to avoid convulsions and seizures. Now, there is always an association of such drugs when the food consumption routine is affected and may influence neuronal imbalance.
3. Arterial blood pH may provide a prominent estimation about the levels of Carbon dioxide and oxygen in the blood as a part of maintaining the blood pH and regulation of O2 and CO2 in the body. Low blood pH may lead to acidosis and can lead to irregularities in the balance between the two mentioned gases and can provide an insight with respect to neuronal associations in terms of consumption of the anticonvulsants.
4. Lactate and pyruvate detection is usually associated with certain inherited conditions regarding the associated hormones such as pyruvate dehydrogenase. There is no specific association of this type of disorder with the condition Jessie is facing. The most important association that should be highlighted is with that of ammonia due to the presence of high protein diet. This indicates that presence of ammonia may be detected in terms of problems associated with urea formation and elimination of ammonia from the body which can be reflected in the disoders associated with liver and kidneys.
5. Apart from this, electrolytes do not reflect any insight besides its role as certain associations related to metabolism and balance.
6. So, the tests should include Ammonia detection and arterial blood pH.