Case of Severe Vitamin D Deficiency Uncovered During a Wellness Visit

Case at a Glance

A 30-year-old male with a history of significant intentional weight loss was found to have severe vitamin D deficiency during a routine health screening. This case highlights common risk factors, including dark skin pigmentation and geographical location, and addresses the rationale behind high-dose, intermittent supplementation.

Patient's Story

A 30-year-old male presented to his primary care physician for a general wellness check-up. The visit was prompted by the patient's recent milestone birthday and a significant, intentional weight loss of 65 lbs over the preceding year. The patient did not report any specific symptoms like bone pain, muscle weakness, or fatigue but was interested in a comprehensive evaluation to ensure his weight loss was achieved healthily. He mentioned a past history of vitamin D deficiency diagnosed 12 years prior during a check-up for rapid weight gain in college, which was treated at the time.

Initial Assessment

The patient appeared healthy and well-nourished. His physical exam was unremarkable. Key risk factors for vitamin D deficiency were noted: the patient is dark-skinned, which reduces cutaneous vitamin D synthesis, and he resides in a northern region with limited sun exposure, particularly in the winter months. His history of a prior deficiency also suggested a predisposition.

The Diagnostic Journey

Given the patient's age and significant change in body weight, a comprehensive blood panel, including a 25-hydroxyvitamin D level, was ordered. While his complete blood count, metabolic panel, and other routine labs were all within normal ranges, the vitamin D level was critically low at <25 nmol/L (laboratory reference range: 75-200 nmol/L). This finding confirmed a severe deficiency that required intervention, despite the patient being asymptomatic.

Final Diagnosis

Severe Vitamin D Deficiency.

Treatment Plan

The patient was prescribed a high-dose weekly regimen of vitamin D (e.g., 50,000 IU of cholecalciferol) for an 8-week repletion period. The physician explained that a large, single weekly dose is a standard and effective method for rapidly correcting severe deficiency. This approach often improves patient adherence compared to a daily dosing schedule. Following the initial treatment course, the plan is to transition the patient to a daily over-the-counter maintenance dose (e.g., 1000-2000 IU) to prevent recurrence.

Outcome and Follow-up

The patient was counseled on the importance of long-term supplementation due to his ongoing risk factors. A follow-up appointment was scheduled in three months to repeat the 25-hydroxyvitamin D test to confirm that his levels have been restored to the normal range and to adjust the maintenance dose if necessary. The case underscores the value of routine screenings in at-risk populations, as significant nutritional deficiencies can exist without overt symptoms.