History of Present Illness
A 26-year-old male firefighter presents to his PCP following an ED visit for an episode of dehydration and severe muscle pain experienced during rigorous physical activity. Yesterday, he fought a fire for an extended period under extreme physical conditions. Despite consuming significant amounts of water, he began feeling lightheaded, experienced severe pain in his calves and shoulders, and noticed dark-colored urine. He was evaluated in the ED and discharged with instructions to hydrate. However, he continues to have dark-colored urine, generalized muscle pain, and fatigue. He reports feeling "like I’ve been hit by a truck."
Review of Systems (ROS)
Positive: Weakness, exhaustion, palpitations, shortness of breath, nausea, dark-colored urine, muscle pain (shoulders, lower back, calves).
Negative: Diarrhea, constipation, anuria, hematuria, muscle weakness, numbness, tingling.
Past Medical History: Recurrent musculoskeletal injuries (shoulder, knee), HTN, and anxiety.
Social History: Moderate alcohol use (occasional beer), no tobacco or drug use. Unmarried in a casual relationship with no children. Active lifestyle
Family History: Mother with breast cancer (remission), father without chronic conditions. Sibling brother with Hx chronic migraines
Allergies: None.
Medications: Ibuprofen 200mg PO q 8 hrs PRN muscle aches, Lisinopril 2.5mg PO daily, Lexapro 10mg PO daily.
Physical Examination
Vitals: T 37.3°C (99.1°F), P 96BPM, RR 12 BPM, BP 134/86, BMI 29.7.
General: A&O; no acute distress; overweight.
Skin: No erythema, pallor, or abnormalities noted.
HEENT: Normal findings.
Lungs: Vesicular breath sounds throughout, equal bilaterally.
Cardiac: Regular rate and rhythm, no murmurs/rubs/gallops.
Abdomen: Soft, mild epigastric tenderness, bilateral flank tenderness, no CVA tenderness.
Musculoskeletal: Tenderness over bilateral shoulders, reduced ROM due to pain, generalized tenderness of calves and quadriceps, severe paralumbar tenderness with guarding and hypertonicity.
Neurological: A&O×3; cranial nerves intact.
Based on the subjective and objective information presented, select and prioritize three differential diagnoses, including each diagnosis's rationale, pathophysiology, and pertinent positives and negatives.
For the working diagnosis, explain why this is the primary diagnosis, what physical findings support the primary diagnosis, and list any additional body systems not addressed in the physical exam and how those physical findings could further support your primary diagnosis.
• List any additional questions you may have inquired about in your history taking that have not already been presented in the HPI and are necessary to establish your diagnosis.
• Address any necessary laboratory or diagnostic testing and the clinical significance of these diagnostics for your diagnosis or ultimate treatment plan.
• Discuss the next appropriate steps in your management and at least two potential complications of this diagnosis untreated.
• Finally, discuss medication management, including pharmacologic and nonpharmacologic choices with appropriate dosing, comprehensive patient education, and follow-up recommendations.
Full Answer Section
Acute Kidney Injury (AKI):
- Rationale: Rhabdomyolysis can lead to AKI due to the release of myoglobin, which can damage the kidneys.
- Pathophysiology: AKI can result from various causes, including decreased blood flow to the kidneys, direct damage to the kidneys, or obstruction of the urinary tract.
- Pertinent Positives: Dark urine, elevated creatinine.
- Pertinent Negatives: No significant fluid overload, normal blood pressure.
3. Heat Stroke:
- Rationale: The patient's exposure to extreme heat and physical exertion could have triggered heat stroke, leading to muscle breakdown and organ damage.
- Pathophysiology: Heat stroke occurs when the body's temperature regulation system fails, leading to hyperthermia and organ damage.
- Pertinent Positives: Muscle pain, weakness, dark urine, and elevated temperature (if present).
- Pertinent Negatives: No significant altered mental status, normal vital signs (except for possible tachycardia).
Working Diagnosis: Rhabdomyolysis
Rationale: Based on the patient's history of intense physical exertion, muscle pain, weakness, dark urine, and elevated CK levels, rhabdomyolysis is the most likely diagnosis.
Physical Exam Findings: Muscle tenderness, especially in the shoulders, calves, and lower back, supports the diagnosis of rhabdomyolysis.
Additional Physical Exam: Neurologic exam to assess for signs of neurologic involvement (e.g., weakness, sensory loss, reflexes).
Additional History Questions:
- Duration of symptoms: How long have the muscle pain, weakness, and dark urine been present?
- Fluid intake: How much fluid has the patient been consuming since the incident?
- Urine output: Has the patient noticed any changes in urine output or color?
- Medications: Are there any medications that could contribute to muscle breakdown or kidney injury?
Laboratory Tests:
- Complete blood count (CBC): To assess for anemia, which can occur with chronic blood loss.
- Basic metabolic panel (BMP): To evaluate renal function and electrolyte balance.
- Creatine kinase (CK): To assess muscle damage.
- Urine analysis and microscopy: To evaluate for myoglobinuria and hematuria.
- Urine myoglobin: To confirm the presence of myoglobin in the urine.
Management:
- Aggressive hydration: Intravenous fluids to maintain adequate urine output and prevent kidney injury.
- Pain management: Oral or intravenous pain medications to alleviate muscle pain.
- Close monitoring: Monitor vital signs, urine output, and electrolyte levels.
- Renal function monitoring: Serial measurements of creatinine and blood urea nitrogen (BUN) to assess kidney function.
- Consultation with nephrologist: For patients with severe rhabdomyolysis or acute kidney injury.
Potential Complications:
- Acute kidney injury
- Compartment syndrome
Medication Management:
- Pain management: Nonsteroidal anti-inflammatory drugs (NSAIDs) like ibuprofen can be used for mild to moderate pain. For severe pain, stronger analgesics like opioids may be necessary.
- Hydration: Oral fluids are sufficient for mild cases. For severe cases, intravenous fluids are required.
- Electrolyte replacement: If electrolyte imbalances are present, appropriate electrolyte solutions should be administered.
Patient Education:
- Importance of adequate hydration, especially during and after intense physical activity.
- Recognition of early signs and symptoms of rhabdomyolysis.
- Importance of seeking medical attention promptly.
- Potential complications of untreated rhabdomyolysis.
Follow-up:
- Follow-up with the primary care physician for monitoring kidney function and muscle recovery.
- Regular follow-up with a nephrologist if necessary.