PA 524 Week 4 Prerenal Versus Intrinsic Brief Example

Course	PA 524 Comprehensive Clinical Module Nephrology & Genitourinary
Week	4
Paper type	Prerenal versus intrinsic brief
Length	About 770 words, 5 pages
Format	APA 7 student paper
School	Chamberlain University
Program	Master of Physician Assistant Studies (MPAS)
Updated	October 2026

Free sample paper for PA 524 Week 4

Prerenal Versus Intrinsic Brief: A Creatinine Rising From 1.4 to 2.3 After Three Days of Norovirus on Lisinopril and a Thiazide, Argued as Prerenal With the Obstruction Door Closed by a 40 mL Bladder Scan

Student Name

Chamberlain University

PA 524: Comprehensive Clinical Module Nephrology & Genitourinary

Instructor Name

Month Day, Year

What this page is doingThe title states the call, the setting and how the third possibility was closed, which tells the reader the brief commits early and checks the alternatives.

The Call

G.H.'s acute kidney injury is prerenal: the kidneys are being underfilled, and the tubules are intact.

What this page is doingOpening with a single committed sentence means every later piece of evidence can be read as support for or against a stated call.

The Setting

Eight months after the clinic catheter visit, and four months after a prostate procedure that resolved the retention, G.H. was admitted on a Friday, three days into a bout of vomiting and loose stools that began during a norovirus outbreak at the senior center. G.H. kept taking lisinopril 20 mg and hydrochlorothiazide 25 mg throughout. Admission creatinine was 2.3 mg/dL; the clinic baseline had been 1.4. Urine output on the ward: 240 mL in the first 12 hours.

Evidence Grouped by Source

For the call, from the bedside: dry mucous membranes; blood pressure 98/58 lying and 82/50 standing, with a pulse rising from 92 to 118; weight 55.4 kg against 58 kg at the last clinic visit.

For the call, from the urine: specific gravity 1.026; urine sodium 14 mmol/L; urine urea 410 mg/dL with a serum urea nitrogen of 62 mg/dL; sediment bland, with a few hyaline casts and no granular or epithelial casts.

For the call, from the arithmetic: fractional excretion of urea about 25 percent, below the 35 percent usually taken to suggest a prerenal state. The urea fraction was used instead of the sodium fraction because the thiazide increases urinary sodium loss and can make a prerenal kidney look as if it were wasting sodium.

For the call, from the blood: a urea nitrogen to creatinine ratio of 62 to 2.3, about 27.

What this page is doingGrouping the evidence by where it came from shows the call rests on independent sources rather than one test repeated in different words.

The Other Side at Full Strength

The case for intrinsic injury is not weak. G.H. is 74, has chronic kidney disease, was hypotensive for at least a day and took an ACE inhibitor and a diuretic through the illness. Prolonged underfilling of the kidney can progress to acute tubular necrosis, and older kidneys are more vulnerable. Hyaline casts can appear in both states. If the low pressure lasted long enough, part of the injury may already be tubular. KDIGO's framework treats prerenal and intrinsic causes as stages that can overlap rather than as fixed categories (Kellum & Lameire, 2013).

What Would Prove It Wrong

The call would be wrong if creatinine kept rising or failed to fall within 24 to 72 hours after volume was restored and the lisinopril and thiazide were held, or if the sediment on a repeat sample showed muddy brown granular casts or renal tubular cells. Either would point to tubular injury. A urine sodium that rose above 40 mmol/L after the thiazide had cleared, with continued poor output, would also count against the call.

The Medicines in the Middle of It

G.H.'s two blood pressure drugs each made the injury worse in a different way. The ACE inhibitor relaxes the outflow arteriole of the glomerulus, which normally helps hold filtration pressure up when blood flow falls; without that support, filtration drops sharply in a dry patient. The thiazide kept pushing salt and water into the urine while G.H. was already losing both from the gut. The chronic kidney disease guideline advises pausing these drugs during dehydrating illness for this reason (Stevens et al., 2024). Neither drug caused tubular damage directly, which is part of why a prerenal call is reasonable: the injury came from pressure and volume, both of which can be restored. G.H. was not taking an anti-inflammatory painkiller, which would have added a third insult to the same mechanism.

Closing the Third Door

Obstruction had to be excluded, given G.H.'s history of retention. A bladder scan after voiding showed 40 mL, and renal ultrasound showed no hydronephrosis on either side. The obstruction door is closed for this episode.

What this page is doingClosing the obstruction possibility with a measurement, not an assumption, is especially important in a patient with a history of retention.

What Happened Next

Lisinopril and hydrochlorothiazide were held, and G.H. received isotonic fluid with close monitoring for overload. By the next morning urine output was 900 mL over 12 hours, and creatinine fell to 1.9, then 1.6 on day three. That course fits the prerenal call. The medicines will be reviewed before discharge rather than restarted automatically, and G.H. was given written sick-day guidance to pause both drugs during any future vomiting or diarrhea.

References

Kellum, J. A., & Lameire, N. (2013). Diagnosis, evaluation, and management of acute kidney injury: A KDIGO summary (Part 1). Critical Care, 17(1), Article 204. https://doi.org/10.1186/cc11454

Stevens, P. E., Ahmed, S. B., Carrero, J. J., Foster, B., Francis, A., Hall, R. K., Herrington, W. G., Hill, G., Inker, L. A., Kazancıoğlu, R., Lamb, E., Lin, P., Madero, M., McIntyre, N., Morrow, K., Roberts, G., Sabanayagam, D., Schaeffner, E., Shlipak, M., . . . Levin, A. (2024). KDIGO 2024 clinical practice guideline for the evaluation and management of chronic kidney disease. Kidney International, 105(4, Suppl.), S117-S314. https://doi.org/10.1016/j.kint.2023.10.018

PA 524 Week 4 instructions, in plain terms

Week four asks for a short brief arguing whether an acute kidney injury is prerenal or intrinsic. Open with a single sentence naming the compartment you are arguing for. Present the evidence grouped by source, bedside findings, urine studies, calculations and blood tests, and include the urine findings as evidence in their own right. Choose the right urine index for your patient and explain the choice if a drug affects it. Then give the opposing compartment a real argument, not a token mention. State what findings or course would prove your call wrong. Address the third possibility, obstruction, and say how it was excluded. Explain how any medicines contributed. If the case continues, show how the course supports or undermines the call. Cite the definitions you use.

Inside the PA 524 Week 4 example

The brief opens with a one-line prerenal call, then sets the scene: an admission eight months after the retention episode, after three days of vomiting and loose stools with lisinopril and hydrochlorothiazide continued. Evidence is grouped: dry mouth, orthostatic hypotension and a 2.6 kg weight loss; specific gravity 1.026, urine sodium 14 and a bland sediment; fractional excretion of urea about 25 percent, chosen because the thiazide distorts sodium excretion; and a urea to creatinine ratio near 27. The intrinsic case is argued from age, hypotension and drugs, citing the KDIGO summary. Conditions that would overturn the call are listed. A 40 mL bladder scan and normal ultrasound close the obstruction question. A drug section, citing KDIGO 2024, explains each drug's role, and the recovery to 1.6 is reported.

PA 524 Week 4 rubric: what full points look like

Faculty grade this brief on commitment and evidence. A brief that hedges between compartments, or reaches its call only at the end, loses the most. Evidence must be grouped by source; a single list mixing exam, urine and blood is marked down. Credit goes to choosing the correct urine index for the patient's medicines and explaining why. The opposing argument must be presented at full strength, and a token sentence costs points. Stating what would prove the call wrong is weighted heavily, as it shows the call is testable. Excluding obstruction with a measurement, rather than assuming, earns its own share. Medication effects and the subsequent course add credit when they are specific. Definitions and indices should be cited.

Common PA 524 Week 4 mistakes, and how to avoid them

The usual problem with this brief is a list of findings and a conclusion that hedges. Send your case findings and medicine list, and the brief we draft would open on the call, group the evidence by source and choose the urine index that suits your patient's drugs. The opposing compartment gets a fair argument before the brief explains why it is less likely. Obstruction is addressed with whatever measurement your case provides. The findings that would overturn the call are listed so the reader can test it. If your case includes the hospital course, it is used to support or question the call. Match each value and index to your own record before the reasoning goes into your submission.

Get a PA-524 Week 4 example written to your instructions

Upload the case your classroom supplies, along with the word limit and whichever citation style is in force, and a custom example built to it comes back inside 24 to 48 hours, the first one free. Where the assignment wants all three compartments argued rather than two, say so and the brief is built that way.

More PA 524 papers and MPAS samples

PA 524 Week 4 questions, answered

The case gives no urine chemistry. Can the brief still commit?

It can, and it says what the commitment is standing on. Without urine values the argument leans harder on the history and the trajectory of the serum figures, and the brief admits that openly rather than writing around the hole. The falsification line then does extra work, naming the urine result that would settle it, and in a sparse case that one line often carries the piece.

How long is a brief supposed to be?

Sections publish different limits and the example is built to whichever one yours states, but the shape holds at any length: the call, the two sets of evidence, the reconciliation, the falsification line. When the limit is tight, the opposing case is compressed rather than cut, because removing it converts an argument back into an assertion and that is the more expensive trade.

Ours asks for a differential instead of a category. Does that change the example?

The evidence work is identical and only the top layer moves. A differential version ranks named conditions and attaches each to a compartment, so the two-sided evidence structure still carries the marks. The generic method for building and narrowing a list belongs to the foundations course your program runs earlier; this week assumes it and spends its space on the three compartments instead.

Where can I find a free PA 524 Week 4 sample paper?

The full PA 524 Week 4 prerenal versus intrinsic brief is on this page, committing to a prerenal call and closing the obstruction door with a bladder scan.

Why does the PA 524 Week 4 sample use fractional excretion of urea?

The patient was taking hydrochlorothiazide, which pushes sodium into the urine and can make a prerenal kidney look as if it were wasting sodium.