Immune Deficiency Testing: When Should You Consider It?

Written by Kristy Beard, MSN, APRN, FNP-C — Board-Certified Family Nurse Practitioner and Founder of Elevate Health and Wellness, serving patients across the Gulf Coast in Gautier, MS and Foley, AL.

When Getting Sick Too Often Is a Clinical Signal

Most adults expect to experience two to four respiratory infections per year — this is within the range of normal immune function even in healthy individuals. But certain patterns of illness should prompt a more thorough clinical evaluation: four or more ear infections in a year, two or more serious sinus infections requiring antibiotics in a year, two or more pneumonias in a two-year period, recurrent deep skin or organ infections, persistent oral or skin thrush in an otherwise healthy adult, or infections with unusual organisms that a healthy immune system would normally control. These patterns — outlined in the warning signs developed by the Jeffrey Modell Foundation — suggest the possibility of an underlying primary or secondary immune deficiency that warrants investigation.

Primary vs. Secondary Immune Deficiency

Primary immunodeficiencies are genetic conditions present from birth in which a specific component of the immune system is absent or functionally impaired. While some are diagnosed in childhood, many — particularly common variable immunodeficiency (CVID), selective IgA deficiency, and specific antibody deficiency — are not identified until adulthood. The average delay from symptom onset to diagnosis of primary immunodeficiency is over 12 years, during which time patients accumulate organ damage from recurrent infections. Secondary immunodeficiencies develop as a consequence of another medical condition or treatment — including HIV infection, malignancy, prolonged corticosteroid use, chemotherapy, organ transplantation, severe malnutrition, or uncontrolled diabetes.

What Immune Deficiency Testing at Elevate Evaluates

At Elevate Health and Wellness, Kristy Beard, MSN, APRN, FNP-C evaluates suspected immune deficiency with a targeted panel that may include complete blood count with differential — evaluating absolute lymphocyte, neutrophil, and natural killer cell counts; immunoglobulin levels (IgG, IgA, IgM, IgE) — which identify humoral immune deficiencies including CVID and selective IgA deficiency; complement levels (C3, C4, CH50) for complement pathway deficiencies; HIV testing when indicated; nutritional markers including vitamin D, zinc, and B12 that significantly affect immune function; and thyroid function, as hypothyroidism produces secondary immune suppression. When initial results suggest a primary immunodeficiency, referral to a clinical immunologist is coordinated for more specialized evaluation.

Nutritional Immune Deficiency: The Most Actionable Finding

The most common and most actionable cause of secondary immune deficiency identified at Elevate is nutritional — particularly deficiencies in vitamin D, zinc, and B12 that significantly impair immune cell development, function, and surveillance. These deficiencies are extremely prevalent on the Gulf Coast, are reliably identified through standard blood testing, and respond predictably to targeted repletion through oral supplementation, injections, or IV therapy. For many patients who present with recurrent infections, addressing underlying nutritional deficiencies produces dramatic improvements in immune resilience without requiring specialist referral or complex immunological treatment.

Concerned about frequent illness or immune function? Learn about our comprehensive lab and primary care services at Elevate in Gautier, MS and Foley, AL.

Sources: Jeffrey Modell Foundation. Warning Signs of Primary Immunodeficiency. info4pi.org. | NIH. Primary Immunodeficiency Diseases. niaid.nih.gov.

This article is written by Kristy Beard, MSN, APRN, FNP-C, board-certified Family Nurse Practitioner and founder of Elevate Health and Wellness. Information provided is for educational purposes only and does not constitute medical advice. Please consult a licensed healthcare provider for personalized care.