In a 70‑year‑old woman with hypertension, type 2 diabetes mellitus, chronic kidney disease stage 3, who was recently hospitalized for acute kidney injury with hyperkalemia (now corrected) and now shows rising BUN and creatinine, falling estimated glomerular filtration rate, normal sodium and potassium, no new symptoms, and intentional fluid restriction, what history of present illness, review of systems, physical examination, assessment, and detailed management plan should be provided?

Clinical Documentation for 70-Year-Old Female with Worsening Renal Function

History of Present Illness

This patient requires immediate nephrology referral and urgent dialysis evaluation given eGFR 24 mL/min/1.73 m² (Stage 4 CKD progressing toward Stage 5), rising BUN and creatinine, and intentional severe fluid restriction causing pre-renal azotemia superimposed on chronic kidney disease. 1

Chief Complaint

Progressive worsening of renal function with rising BUN (46 mg/dL) and creatinine (2.2 mg/dL), declining eGFR (24 mL/min/1.73 m²) over 2-week period following recent hospitalization for AKI with hyperkalemia.

Present Illness Details

• Recent hospitalization: AKI with hyperkalemia (now corrected)
• Current laboratory trends 2:
  • BUN: 31 → 33 → 46 mg/dL (progressive elevation)
  • Creatinine: 1.6 → 1.8 → 2.2 mg/dL (37% increase from baseline)
  • eGFR: 35 → 30 → 24 mL/min/1.73 m² (31% decline, now Stage 4 CKD)
  • Sodium and potassium: within normal limits
• Critical behavioral factor: Patient intentionally restricts fluid intake to avoid urination, creating pre-renal component
• Symptom status: Denies uremic symptoms (nausea, vomiting, pruritus, altered mental status, dyspnea)
• Medication review needed: Assess for nephrotoxic agents (NSAIDs), ACE inhibitors/ARBs (may cause reversible GFR decline), diuretics 3

Review of Systems

Constitutional

• Fatigue or weakness (uremic symptoms) 1
• Unintentional weight changes
• Fever or chills (infection risk)

Cardiovascular

• Chest pain or palpitations (hyperkalemia risk, though currently normal K+) 2
• Orthopnea or paroxysmal nocturnal dyspnea (volume overload) 3
• Lower extremity edema 3

Respiratory

• Dyspnea at rest or with exertion (metabolic acidosis, volume overload) 1
• Cough (pulmonary edema)

Gastrointestinal

• Nausea, vomiting, anorexia (uremic symptoms) 1
• Diarrhea or constipation
• Abdominal pain

Genitourinary

• Urine output volume and frequency (oliguria indicates worsening kidney function) 3
• Dysuria, hematuria
• Nocturia patterns

Neurological

• Confusion, altered mental status (uremic encephalopathy) 1
• Seizures
• Peripheral neuropathy symptoms

Musculoskeletal

• Muscle weakness (electrolyte abnormalities, uremia) 2
• Bone pain (metabolic bone disease in CKD) 3

Integumentary

• Pruritus (uremia) 1
• Easy bruising (uremic platelet dysfunction)

Physical Examination

Vital Signs

• Blood pressure (assess for hypertension vs. hypotension from volume depletion) 3
• Heart rate and rhythm (arrhythmia risk with electrolyte shifts) 2
• Respiratory rate (Kussmaul respirations suggest metabolic acidosis) 1
• Temperature (infection)
• Weight (compare to recent hospitalization for volume status) 3
• Oxygen saturation

General Appearance

• Level of alertness and orientation (uremic encephalopathy) 1
• Signs of distress or uremic appearance

Cardiovascular

• Jugular venous pressure (volume status assessment) 3
• Heart sounds (pericardial friction rub indicates uremic pericarditis) 1
• Peripheral pulses
• Capillary refill

Respiratory

• Lung auscultation for crackles (volume overload) or clear fields 3
• Work of breathing

Abdominal

• Distension, tenderness
• Bowel sounds
• Organomegaly

Extremities

• Edema (pitting vs. non-pitting, location, severity) 3
• Skin turgor and mucous membrane moisture (volume depletion from fluid restriction) 3
• Asterixis (uremic encephalopathy) 1

Skin

• Uremic frost (severe uremia) 1
• Excoriations from pruritus
• Pallor (anemia of CKD) 3

Neurological

• Mental status examination
• Focal deficits
• Reflexes

Assessment

Primary Diagnosis

Acute-on-chronic kidney disease (Stage 4 CKD, eGFR 24 mL/min/1.73 m²) with pre-renal azotemia secondary to intentional severe fluid restriction, in a patient with hypertension, type 2 diabetes mellitus, and recent AKI with hyperkalemia. 3

Supporting Evidence

• Progressive renal dysfunction: 37% creatinine increase and 31% eGFR decline over 2 weeks indicates acute component 3
• Pre-renal component: BUN:Cr ratio >20:1 (46:2.2 = 20.9) with intentional fluid restriction 3
• Stage 4 CKD: eGFR 24 mL/min/1.73 m² places patient at high risk for progression to Stage 5 (kidney failure) 3, 1
• Diabetes and hypertension: Major risk factors for CKD progression 3

Differential Considerations

• Medication-induced AKI (ACE inhibitors, ARBs, NSAIDs, diuretics) 3
• Contrast-induced nephropathy (if recent imaging)
• Urinary obstruction (requires imaging)
• Rapidly progressive glomerulonephritis (less likely without hematuria/proteinuria)
• Atheroembolic disease

Complications to Monitor

• Electrolyte abnormalities (hyperkalemia recurrence, hypocalcemia, hyperphosphatemia, hypomagnesemia) 3, 2, 4
• Metabolic acidosis 3, 1
• Volume overload vs. dehydration 3
• Anemia of CKD 3
• Metabolic bone disease 3
• Uremic complications (pericarditis, encephalopathy, bleeding) 1

Detailed Management Plan

Immediate Actions (Within 24 Hours)

1. Urgent Nephrology Referral

Immediate nephrology consultation is mandatory given eGFR <30 mL/min/1.73 m² and rapid decline, with preparation for potential kidney replacement therapy. 3, 1

• eGFR 24 mL/min/1.73 m² is approaching absolute indication for RRT planning (eGFR <15) 1
• Risk of kidney failure within 1 year exceeds 20% threshold for timely referral 1
• Nephrology will assess need for urgent vs. elective dialysis initiation 1

2. Comprehensive Laboratory Assessment

Obtain complete metabolic panel, arterial blood gas, complete blood count, phosphate, magnesium, calcium, parathyroid hormone, and urinalysis with microscopy within 6 hours. 3, 2, 4

Critical laboratory monitoring 2:

• Electrolytes every 6-12 hours initially given recent hyperkalemia and Stage 4 CKD 2
• Serum potassium (target 4.0-5.0 mmol/L to prevent cardiac arrhythmias) 2
• Sodium, chloride, bicarbonate (assess for metabolic acidosis) 3, 1
• Phosphate (hyperphosphatemia common in CKD) 3, 4
• Magnesium (hypomagnesemia in 12% of hospitalized patients) 3, 4
• Calcium (hypocalcemia in CKD) 3, 4
• Complete blood count (anemia of CKD) 3
• Arterial blood gas if bicarbonate <22 mEq/L (metabolic acidosis assessment) 1
• Parathyroid hormone and 25-hydroxyvitamin D (metabolic bone disease) 3

Urinalysis with microscopy 3:

• Assess for proteinuria, hematuria, casts
• Urine albumin-to-creatinine ratio (UACR) 3
• Spot urine sodium and creatinine (calculate fractional excretion of sodium to confirm pre-renal etiology)

3. Medication Reconciliation and Adjustment

Immediately review and adjust all medications for eGFR 24 mL/min/1.73 m², discontinue nephrotoxins, and assess ACE inhibitor/ARB dosing. 3, 1

ACE inhibitor/ARB management 3:

• Continue ACE inhibitor or ARB even with eGFR <30 mL/min/1.73 m² unless creatinine rose >30% within 4 weeks of initiation 3
• Check serum creatinine and potassium 2-4 weeks after any dose adjustment 3
• Small elevations in creatinine (up to 30%) with RASi are expected and renoprotective, not true AKI 3
• Consider dose reduction only if symptomatic hypotension, uncontrolled hyperkalemia despite treatment, or to reduce uremic symptoms 3

Discontinue or adjust 3, 1:

• NSAIDs (nephrotoxic, increase hyperkalemia risk) 3, 1
• Potassium-sparing diuretics if hyperkalemia recurs 2, 1
• Metformin if eGFR <30 mL/min/1.73 m² (lactic acidosis risk)
• All medications requiring renal dose adjustment 1

Avoid 3:

• Iodinated contrast (contrast-induced nephropathy risk) 3
• Aminoglycosides and other nephrotoxic antibiotics

4. SGLT2 Inhibitor Consideration

Initiate SGLT2 inhibitor (empagliflozin, dapagliflozin, or canagliflozin) given type 2 diabetes and eGFR ≥20 mL/min/1.73 m². 3

• Strong 1A recommendation for patients with T2D, CKD, and eGFR ≥20 mL/min/1.73 m² 3
• Continue even if eGFR falls below 20 unless not tolerated or KRT initiated 3
• Withhold during prolonged fasting, surgery, or critical illness (ketosis risk) 3
• Does not require alteration of CKD monitoring frequency 3
• Reversible eGFR decrease on initiation is not indication to discontinue 3

5. Fluid Management Strategy

Implement structured hydration protocol with goal of 1.5-2 liters daily oral fluid intake, with patient education on importance of adequate hydration to prevent pre-renal azotemia. 3, 1

Rationale:

• Current intentional fluid restriction is causing pre-renal component (BUN:Cr ratio >20:1) 3
• Adequate hydration essential to prevent further AKI 3
• Avoid aggressive IV fluids given Stage 4 CKD and volume overload risk 1
• If IV fluids needed, use balanced crystalloids rather than 0.9% saline 1

Patient education 3:

• Explain that adequate fluid intake will not worsen kidney function
• Discuss strategies to manage urinary frequency (timed voiding, pelvic floor exercises)
• Consider urology referral if overactive bladder symptoms present

Short-Term Management (1-7 Days)

6. Hyperkalemia Prevention and Monitoring

Implement hyperkalemia prevention protocol with dietary potassium restriction (2-3 g/day), medication review, and frequent potassium monitoring every 6-12 hours initially. 2, 5, 6, 7

Dietary modifications 5, 7:

• Restrict dietary potassium to 2-3 g/day (2000-3000 mg/day)
• Avoid high-potassium foods (bananas, oranges, tomatoes, potatoes, salt substitutes)
• Dietitian consultation for renal diet education

Monitoring strategy 2:

• Serum potassium every 6-12 hours for first 48 hours 2
• Then daily until stable
• Obtain ECG immediately if potassium >6.0 mmol/L 2
• Target potassium 4.0-5.0 mmol/L 2

Rule out pseudohyperkalemia 2:

• Repeat measurement with proper technique if elevated
• Avoid repeated fist clenching during phlebotomy 2
• Consider arterial sample if hemolysis suspected 2

Risk factors present 5:

• eGFR <45 mL/min/1.73 m² (patient has eGFR 24) 5
• Diabetes mellitus 5
• Likely on ACE inhibitor or ARB 5

If hyperkalemia recurs 6, 7, 8:

• Consider newer potassium binders (patiromer or sodium zirconium cyclosilicate) to allow continuation of RASi therapy 6, 8
• Avoid discontinuing ACE inhibitor/ARB if possible, as this increases mortality 6, 8

7. Metabolic Acidosis Management

Monitor for metabolic acidosis with serum bicarbonate and arterial blood gas; treat if bicarbonate <22 mEq/L with oral sodium bicarbonate 650-1300 mg three times daily. 3, 1

• Metabolic acidosis common in Stage 4-5 CKD 3
• Check serum bicarbonate and anion gap 1
• If bicarbonate <22 mEq/L, initiate oral sodium bicarbonate 3
• Monitor for volume overload with sodium bicarbonate therapy 3

8. Anemia Assessment and Management

Check hemoglobin, iron studies (serum iron, TIBC, ferritin, transferrin saturation); initiate erythropoiesis-stimulating agent if hemoglobin <10 g/dL and iron replete. 3

• Anemia of CKD expected with eGFR <30 mL/min/1.73 m² 3
• Iron deficiency common; supplement if ferritin <100 ng/mL or transferrin saturation <20% 3
• Target hemoglobin 10-11.5 g/dL (avoid >13 g/dL due to cardiovascular risk) 3

9. Mineral Bone Disease Evaluation

Assess calcium, phosphate, parathyroid hormone, and 25-hydroxyvitamin D; initiate phosphate binders if phosphate >5.5 mg/dL and vitamin D supplementation if deficient. 3

• Metabolic bone disease common in CKD 3
• Check PTH, calcium, phosphate, vitamin D 3
• Restrict dietary phosphate to 800-1000 mg/day 3
• Initiate phosphate binders with meals if hyperphosphatemia present 3
• Supplement vitamin D if 25(OH)D <30 ng/mL 3

10. Blood Pressure Management

Target blood pressure <130/80 mmHg using ACE inhibitor or ARB as first-line agent, with addition of other antihypertensives as needed. 3

• Hypertension accelerates CKD progression 3
• Continue ACE inhibitor or ARB for renoprotection 3
• Add calcium channel blocker or diuretic if needed for BP control 3
• Monitor BP at every visit 3

Medium-Term Management (1-4 Weeks)

11. Renal Replacement Therapy Planning

Initiate comprehensive RRT education covering hemodialysis, peritoneal dialysis, kidney transplantation, and conservative management options. 1

Patient and family education 1:

• Hemodialysis (in-center vs. home)
• Peritoneal dialysis (continuous ambulatory vs. automated)
• Kidney transplantation (living vs. deceased donor)
• Conservative management (supportive care without dialysis)

Vascular access planning 1:

• Refer to vascular surgery for arteriovenous fistula creation if hemodialysis anticipated
• Fistula requires 3-6 months to mature before use
• Avoid venipuncture and blood pressure measurements in non-dominant arm (preserve veins)

Peritoneal dialysis catheter 1:

• Consider if patient prefers home-based therapy
• Requires abdominal surgery for catheter placement

Transplant evaluation 1:

• Refer to transplant center if candidate
• Living donor evaluation if available

12. Nutritional Management

Refer to renal dietitian for comprehensive dietary counseling on protein restriction (0.8 g/kg/day), potassium restriction (2-3 g/day), phosphate restriction (800-1000 mg/day), and sodium restriction (<2 g/day). 3, 4

Dietary recommendations 3, 4:

• Protein: 0.8 g/kg/day (avoid excessive restriction to prevent malnutrition)
• Potassium: 2-3 g/day (2000-3000 mg/day)
• Phosphate: 800-1000 mg/day
• Sodium: <2 g/day (2000 mg/day)
• Fluid: 1.5-2 liters/day (adjust based on urine output and volume status)
• Calories: adequate to maintain body weight

Micronutrient supplementation 3:

• Water-soluble vitamins (B-complex, vitamin C, folate) often deficient in CKD 3
• Avoid vitamin A supplementation (accumulates in kidney failure)
• Monitor and supplement thiamine, vitamin B6, folate 3

13. Diabetes Management

Optimize glycemic control with target HbA1c <7% using renal-dosed medications; discontinue metformin given eGFR <30 mL/min/1.73 m². 3

• Adjust all diabetes medications for eGFR 24 mL/min/1.73 m² 3
• Discontinue metformin (lactic acidosis risk with eGFR <30) 3
• SGLT2 inhibitor appropriate (see above) 3
• Insulin often required in advanced CKD (reduced clearance, adjust doses)
• Monitor glucose every 4-6 hours if hospitalized 3

14. Cardiovascular Risk Reduction

Initiate statin therapy for cardiovascular risk reduction and optimize management of hypertension and diabetes. 3

• CKD is cardiovascular disease equivalent 3
• Statin therapy reduces cardiovascular events in CKD 3
• Aspirin for secondary prevention if indicated
• Smoking cessation counseling if applicable

Long-Term Management (>1 Month)

15. Ongoing Monitoring Schedule

Establish regular follow-up schedule with nephrology every 2-4 weeks initially, then monthly once stable, with laboratory monitoring every 1-3 months. 3

Laboratory monitoring frequency 3:

• Stage 4 CKD: every 3-5 months when stable 3
• More frequent (every 1-3 months) given recent AKI and rapid decline 3
• Electrolytes, BUN, creatinine, eGFR 3
• Calcium, phosphate, PTH, vitamin D 3
• Hemoglobin, iron studies 3
• Urinalysis and UACR 3

Clinical monitoring 3:

• Blood pressure at every visit 3
• Weight and volume status 3
• Medication review and adjustment 3
• Assessment for uremic symptoms 1
• Evaluation for CKD complications 3

16. Advance Care Planning

Initiate advance care planning discussions regarding goals of care, dialysis preferences, and end-of-life wishes. 1

• Discuss prognosis and expected disease trajectory
• Document advance directives
• Identify healthcare proxy
• Discuss quality of life priorities
• Consider palliative care consultation if conservative management preferred

Critical Pitfalls to Avoid

Do not delay nephrology consultation waiting for further deterioration; urgent dialysis may be needed if hyperkalemia worsens, acidosis progresses, or uremic symptoms develop. 1

Avoid discontinuing ACE inhibitor/ARB solely due to eGFR <30 mL/min/1.73 m² or small creatinine increases (<30%); these medications provide critical renoprotection and cardiovascular benefit. 3

Do not aggressively administer IV fluids given Stage 4 CKD and volume overload risk; use balanced crystalloids rather than 0.9% saline if IV fluids needed. 1

Pseudohyperkalemia must always be ruled out before aggressive treatment by repeating measurement with proper technique or obtaining arterial sample. 2

Review all medications that can cause hyperkalemia (RASi, potassium-sparing diuretics, NSAIDs, beta-blockers, trimethoprim-sulfamethoxazole, heparin, calcineurin inhibitors) and discontinue or dose-adjust as necessary. 2, 1

All nephrotoxic medications should be discontinued or dose-adjusted for eGFR <30 mL/min/1.73 m². 1

Avoid venipuncture and blood pressure measurements in non-dominant arm to preserve veins for future vascular access. 1

Do not wait until eGFR <15 mL/min/1.73 m² to initiate RRT planning; vascular access creation requires 3-6 months for fistula maturation. 1