How to manage a 61-year-old female patient with sciatic hip pain, hyperglycemia (elevated glucose), hypouricemia (low Blood Urea Nitrogen (BUN)), low BUN/Creatinine ratio, hyponatremia (low sodium), and vitamin D deficiency (low 25-Hydroxy vitamin D level)?

Management Based on Laboratory Abnormalities

This 61-year-old female with sciatic hip pain requires immediate vitamin D supplementation at 50,000 IU weekly for 8 weeks, followed by maintenance dosing of 800-1,000 IU daily, along with calcium supplementation of 1,000-1,500 mg daily. 1, 2

Vitamin D Deficiency (22.2 ng/mL) - Primary Concern

The vitamin D level of 22.2 ng/mL represents insufficiency (defined as 20-30 ng/mL) and requires aggressive repletion, particularly given the association with hip pain. 2

Treatment Protocol:

• Initiate ergocalciferol (vitamin D2) 50,000 IU orally weekly for 8 weeks to normalize vitamin D levels 2
• After normalization, transition to cholecalciferol (vitamin D3) 800-1,000 IU daily for maintenance 2
• Add calcium supplementation 1,000-1,500 mg daily in divided doses for optimal absorption 1
• Recheck 25-hydroxyvitamin D levels after 3 months to ensure adequate response, targeting levels >30 ng/mL 1

Clinical Rationale:

• Moderate vitamin D deficiency (12.5-25 nmol/L) independently predicts worsening knee and hip pain over 5 years in older adults 3
• Vitamin D deficiency is highly prevalent (74.3%) in patients with spinal stenosis and severe pain, and correlates with hip pain severity 4, 5
• The patient's sciatic hip pain may be partially attributable to vitamin D deficiency, which commonly manifests as symmetric low back pain, proximal muscle weakness, and throbbing bone pain 2

Bone Health Assessment Required

Order a DXA scan immediately to assess for osteoporosis given the vitamin D deficiency and hip pain. 1

• The combination of age 61 years, vitamin D insufficiency, and hip pain places this patient at elevated fracture risk 1
• If DXA demonstrates osteoporosis (T-score ≤-2.5) or osteopenia with fragility fractures, bisphosphonate therapy should be initiated after correcting vitamin D deficiency 6, 1
• Critical pitfall: Never initiate bisphosphonates before correcting vitamin D deficiency, as this can lead to increased fragility and fractures due to unrecognized osteomalacia 6

Mild Hyperglycemia (108 mg/dL)

The fasting glucose of 108 mg/dL indicates impaired fasting glucose (prediabetes) but does not require pharmacologic intervention at this time. 7

• Lifestyle modifications including dietary counseling and regular physical activity should be emphasized 6
• Recheck fasting glucose and consider hemoglobin A1C in 3-6 months 7
• Metformin is not indicated unless fasting glucose consistently exceeds 126 mg/dL or A1C ≥6.5% 7

Mild Hyponatremia (133 mmol/L)

The sodium of 133 mmol/L represents mild hyponatremia (normal 134-144 mmol/L) and requires assessment of volume status and medication review. 6

• Evaluate for symptoms of hyponatremia (confusion, weakness, nausea) - if asymptomatic, no immediate intervention needed 6
• Review medications for potential SIADH-inducing agents
• If persistent, check serum osmolality, urine sodium, and urine osmolality to determine etiology 6
• Avoid rapid correction; gradual increase through fluid restriction or addressing underlying cause is preferred 6

Low BUN (4 mg/dL) and Low BUN/Creatinine Ratio (7)

The low BUN with normal creatinine suggests either low protein intake or increased fluid intake, neither requiring specific intervention. 6

• The eGFR of 103 mL/min/1.73m² confirms normal renal function 6
• No treatment needed unless associated with malnutrition - assess dietary protein intake
• This pattern does not indicate renal pathology given normal creatinine and eGFR 6

Macrocytosis (MCV 100 fL)

The elevated MCV of 100 fL (normal 79-97 fL) with borderline low RBC requires evaluation for vitamin B12 and folate deficiency. 1

• Order serum vitamin B12, folate, and methylmalonic acid levels 1
• If B12 deficiency confirmed, initiate replacement therapy
• The normal hemoglobin (12.1 g/dL) suggests this is not causing symptomatic anemia currently 1

Follow-Up Timeline

• Week 8-12: Recheck 25-hydroxyvitamin D, calcium, and PTH levels 1
• Week 12: Obtain DXA scan results and determine need for bisphosphonate therapy 1
• Month 3: Reassess fasting glucose and consider A1C 7
• Month 3: Recheck CBC with B12/folate if macrocytosis workup initiated 1
• Month 6: Follow-up sodium if persistently low 6

Hip Pain Management Considerations

While addressing vitamin D deficiency, consider physical therapy for hip-related pain as first-line treatment. 6

• Exercise-based treatments should be at least 3 months duration for hip pain 6
• If conservative management fails after vitamin D repletion, consider intra-articular corticosteroid injection under fluoroscopic guidance 8
• NSAIDs may be used for symptomatic relief if no contraindications exist 6
• Avoid opioids for chronic hip pain 8