| Course | NU104 Pathophysiology for Nursing |
|---|---|
| Unit | Unit 8 |
| Paper type | Case study analysis |
| Length | About 850 words, 6 pages double-spaced |
| Format | APA 7 student paper |
| School | Purdue University Global |
| Program | BSN (prelicensure) |
| Updated | October 2026 |
Free sample paper for NU104 Unit 8
A Gland That Stopped Listening to Calcium: A Case Study Analysis of Primary Hyperparathyroidism From a Single Adenoma in a Composite 59-Year-Old Woman, With Kidney Stones, Thinning Bone and a Feedback Loop That No Longer Closes
[Student Name]
Purdue University Global
NU104: Pathophysiology for Nursing
Unit 8 Case Study Analysis
[Instructor Name]
[Date]
The patient is a composite; laboratory values are typical for the condition and bracketed where illustrative.
The Case
[Ruth], a composite 59-year-old school librarian, comes to the clinic after passing a second kidney stone in twelve months. She also mentions being tired, constipated and more forgetful than usual, which she had blamed on menopause and a busy year. Her blood calcium is [11.2] mg/dL, above the normal range, and her parathyroid hormone (PTH) is [128] pg/mL, also high. Her phosphate is low, her vitamin D level is adequate, and her kidney function is normal. A bone density scan shows thinning at the forearm. Imaging later finds a single enlarged parathyroid gland.
How the Loop Normally Works
Four small parathyroid glands sit behind the thyroid. Their cells carry calcium-sensing receptors on their surfaces. When blood calcium falls, fewer receptors are activated and the glands release more PTH. PTH then raises calcium in three ways: it releases calcium from bone by stimulating bone breakdown, it increases calcium reabsorption in the kidney while increasing phosphate loss, and it activates vitamin D in the kidney, which increases calcium absorption from the gut. As calcium rises back to normal, the receptors are activated again and PTH secretion falls. This is a classic negative feedback loop: the product of the system, calcium, switches off the signal that produced it (Rogers, 2023).
What Went Wrong in Ruth
In primary hyperparathyroidism, the problem lies in the gland itself. In about 80 to 85 percent of cases it is a single benign tumor, an adenoma (Bilezikian, 2018). The adenoma cells have fewer working calcium-sensing receptors or need a higher calcium level to switch off. They keep secreting PTH even when blood calcium is already high.
That is why Ruth's two values belong together. In a working loop, high calcium should come with low PTH. A high calcium with a high PTH means the gland is no longer responding to calcium: the loop has been opened. A high calcium with a low PTH would point elsewhere, for example to a cancer releasing a PTH-like protein, so reading the two values together is what identifies the source (Walker & Silverberg, 2018).
The diagnosis rests on a pair of numbers that should never rise together: a high calcium should have silenced the gland.
Connecting Each Finding to the Mechanism
Kidney stones. PTH raises calcium reabsorption in the kidney, yet so much calcium is filtered when blood levels are high that urinary calcium rises overall. Calcium combines with oxalate or phosphate in concentrated urine and forms crystals, which grow into stones.
Thinning bone. Continuous PTH stimulates bone breakdown more than formation. Bone at the forearm, which is rich in the dense outer layer of bone, tends to show loss first in this condition, which is why her scan was abnormal there (Bilezikian, 2018).
Low phosphate. PTH makes the kidney excrete phosphate, so blood phosphate falls.
Fatigue, constipation and forgetfulness. High calcium reduces the excitability of nerves and muscles. In the gut, slower smooth muscle activity causes constipation; in the brain, it can cause tiredness, low mood and poor concentration. These vague symptoms are easy to overlook, which is part of why the condition is often found on a routine blood test.
Why the Kidneys Are Still Normal
Ruth's kidney function remains normal, but persistent hypercalcemia and recurrent stones can damage the kidney over years, and high calcium can impair the kidney's ability to concentrate urine, causing increased urination and thirst. Her normal function is one reason the problem has been found at a stage when it can be corrected without lasting kidney harm. Finding it now also spares her bone further loss, since bone density often improves after the excess hormone is removed.
Ruling Out Other Causes
Low vitamin D can raise PTH by lowering calcium, but then calcium is low or normal, not high, and the PTH rise is an appropriate response rather than a broken loop. Her adequate vitamin D level and high calcium point away from that. Certain diuretics and lithium can also raise calcium; her medication list includes neither. A rare inherited condition, in which the kidney excretes very little calcium, can mimic the pattern and is checked with a urine calcium test (Walker & Silverberg, 2018).
Course and Nursing Relevance
Surgical removal of the single adenoma usually cures the condition. Because the remaining glands have been suppressed by high calcium, calcium can fall below normal for a few days after surgery, so nurses ask about numbness of the lips or fingertips and watch for cramping. Before surgery, adequate fluid intake helps reduce the risk of further stones. For Ruth, the case also shows why a normal-looking symptom list should not end the investigation when a lab value does not fit.
References
Bilezikian, J. P. (2018). Primary hyperparathyroidism. The Journal of Clinical Endocrinology & Metabolism, 103(11), 3993-4004. https://doi.org/10.1210/jc.2018-01225
Rogers, J. L. (Ed.). (2023). McCance & Huether's pathophysiology: The biologic basis for disease in adults and children (9th ed.). Elsevier.
Walker, M. D., & Silverberg, S. J. (2018). Primary hyperparathyroidism. Nature Reviews Endocrinology, 14(2), 115-125. https://doi.org/10.1038/nrendo.2017.104
NU104 Unit 8 instructions, in plain terms
Unit 8 usually turns to the endocrine system and asks for a case in which a feedback loop has stopped working. Prompts commonly want the normal loop described, the point where it fails identified, the laboratory pattern interpreted and each finding in the case explained. A paper of roughly three to four pages fits most prompts, and graders check for a clear statement of what the hormone does and what normally turns it off, and for paired laboratory values read together, since the pairing usually identifies where the problem lies. Every symptom should be linked to the mechanism, including vague ones. Many rubrics also reward ruling out a similar condition by a specific feature and a brief note on nursing care tied to the mechanism.
How this NU104 Unit 8 example is built
The analysis begins with the case: two stones, fatigue, constipation, forgetfulness, and laboratory results including calcium, hormone, phosphate and vitamin D. The normal loop follows, with the three ways parathyroid hormone raises calcium and the receptor that shuts it off. The section on what went wrong explains how adenoma cells lose their response to calcium, with the highlighted line on a pair of numbers that should never rise together. Each finding then gets a short paragraph. A section explains why her kidneys are still normal and what earlier detection spares. Other causes are ruled out by named features, and the analysis closes with surgery and postoperative monitoring for low calcium.
Where the points sit in the NU104 Unit 8 rubric
Case study analyses in NU 104 tend to be graded on understanding of normal physiology, identification of the failure, explanation of findings, and clinical reasoning. Normal physiology earns credit when the hormone's actions and its feedback control are described correctly. Identification points go to analyses that locate the failure precisely and use paired laboratory values to support it. Explanation of findings is weighted heavily and rewards linking every symptom and result to a mechanism. Clinical reasoning covers ruling out look-alike conditions and connecting nursing care to the physiology, such as watching for low calcium after surgery. APA 7 sources and organized headings make up the remainder.
Common NU104 Unit 8 mistakes, and how to avoid them
Analyses often describe the hormone's effects without explaining what normally switches it off, which leaves the broken loop unexplained. Another common error is reading calcium and hormone levels separately, when it is the combination that matters. Vague symptoms such as fatigue are sometimes left out because they seem unimportant, though they are part of the picture. Some papers jump straight to surgery without explaining why calcium may fall afterward. Describe the loop first, read paired values together, account for every symptom, rule out at least one similar condition by a specific test or feature, and link each nursing observation to the mechanism behind it.
Get an NU104 Unit 8 example written to your instructions
Upload the Unit 8 endocrine case and the rubric your section attached. Whether it involves diabetes, thyroid disease or adrenal failure, your free first case study analysis follows that case and those criteria, and it arrives in 24-48h. The patient in it remains a composite drawn from typical features. The paper above is an original model document written by our desk, not a submitted student paper and not an official Purdue University Global document.
More NU104 papers and BSN samples
- NU104 Unit 1: Discussion Board Post
- NU104 Unit 2: Concept Map
- NU104 Unit 3: Case Study Analysis
- NU104 Unit 4: Mechanism Write-Up
- NU104 Unit 5: Systems Review
- NU104 Unit 6: Seminar Reflection
- NU104 Unit 7: Lab Value Interpretation
- NU104 Unit 9: Concept Map
- NU104 Unit 10: Final Synthesis Paper
NU104 Unit 8 questions, answered
Where can I find a free NU104 Unit 8 sample paper?
This page holds the complete NU104 Unit 8 case study analysis of primary hyperparathyroidism, from the normal feedback loop and the adenoma to each finding, look-alikes and postoperative care, with three references. A custom endocrine case analysis can be written for your own section.
Why is high calcium with high PTH abnormal?
In a working loop, high calcium activates receptors on the parathyroid glands and switches hormone release off. A high hormone level despite high calcium means the gland has stopped responding, which is the hallmark of primary hyperparathyroidism.
How does hyperparathyroidism cause kidney stones?
So much calcium is filtered when blood levels are high that urinary calcium rises even though the hormone increases reabsorption. Calcium combines with oxalate or phosphate in concentrated urine and forms stones.
Why can calcium fall after parathyroid surgery?
The remaining glands have been suppressed by months of high calcium and take days to recover. Until they do, calcium can drop, so nurses watch for numbness of the lips or fingertips and cramping.
What else can raise PTH in NU104 Unit 8?
Low vitamin D can raise the hormone by lowering calcium, but then calcium is low or normal. Certain diuretics, lithium and a rare inherited condition can also mimic the pattern and are checked before diagnosis.