Presentations in Adults
PIDs are not exclusively childhood diseases. Several common PIDs — including Common Variable Immunodeficiency (CVID), the most frequent symptomatic antibody deficiency — often present in the second or third decade of life.
In adults, the warning pattern includes:
– Recurrent pneumonias or sinusitis requiring hospital admission
– Unusually severe or prolonged viral infections
– Recurrent shingles at a young age
– Unexplained bronchiectasis (permanent widening and damage of the airways)
– Autoimmune complications (autoimmune cytopenias, inflammatory bowel disease, granulomatous disease) alongside recurrent infections
– An average delay of 8–12 years from symptom onset to diagnosis of CVID is documented globally — awareness matters
What Is Not Primary Immunodeficiency
Not every pattern of recurrent infection indicates immunodeficiency. Other common explanations include:
- Allergy (allergic rhinitis and adenoid hypertrophy causing recurrent ear and sinus infections in children)
- Anatomical problems (deviated nasal septum, Eustachian tube dysfunction)
- Environmental factors (passive cigarette smoke, crowded childcare settings)
- Uncontrolled conditions such as diabetes mellitus (which impairs immune function but is secondary, not primary)
The evaluation of PID is a specialist task. The purpose of the 10 Warning Signs is not to diagnose — it is to prompt referral.
What to Expect at an Immunology Evaluation
A clinical immunologist will assess:
History: Age of onset, types of organisms causing infections (bacterial vs fungal vs viral vs opportunistic), hospitalisations, response to antibiotics, family history, and vaccination status.
Initial blood tests:
– Complete blood count with differential (looking at lymphocyte and neutrophil counts)
– Immunoglobulin levels (IgG, IgA, IgM, IgE)
– Complement levels (C3, C4, CH50)
– Vaccine antibody titres (responses to prior vaccinations)
Specialist tests depending on clinical picture:
– Lymphocyte subset panels (T cells, B cells, NK cells)
– Neutrophil function testing (dihydrorhodamine — DHR — assay for CGD)
– Genetic testing where a specific disorder is suspected
Treatment Overview
Treatment depends on the specific PID:
Immunoglobulin replacement therapy — for antibody deficiency disorders (CVID, X-linked agammaglobulinaemia, and others). Immunoglobulin is given intravenously (IVIG) or subcutaneously (SCIG) every 3–4 weeks or weekly, replacing the antibodies the patient cannot produce. This is transformative — patients who were hospitalised multiple times per year become able to live near-normal lives.
Haematopoietic stem cell transplantation (HSCT) — curative for several severe PIDs, including SCID. Must be performed early in life for best outcomes. HSCT for PID is performed at a small number of centres in India.
Prophylactic antibiotics — for certain phagocyte disorders and complement deficiencies.
Gene therapy — now available or in late-stage trials for several specific PIDs (ADA-SCID, X-linked SCID). Not yet widely available in India.
Enzyme replacement therapy — for ADA deficiency.
Supportive care — aggressive treatment of acute infections, avoidance of live vaccines where contraindicated, and monitoring for complications including autoimmunity and lymphoma (which are elevated risks in CVID).
India-Specific Context
PID diagnosis in India is substantially delayed relative to high-income countries. Reasons include:
- Infectious diseases are more common, so recurrent infections are attributed to environmental exposure rather than host immune deficiency
- Specialist availability is limited — fewer than 100 trained clinical immunologists practice in India
- Genetic testing is expensive and not always available in smaller centres
- Awareness among general practitioners and paediatricians is low
Despite this, several centres in India — including NIMS Hyderabad, AIIMS, CMC Vellore, and PGIMER — have established immunology programmes with immunoglobulin replacement capacity.
Frequently Asked Questions
Are primary immunodeficiency diseases the same as HIV/AIDS?
No. HIV/AIDS is a secondary (acquired) immunodeficiency caused by a virus. Primary immunodeficiency diseases are genetic — they are present from birth and result from inborn errors in immune system development or function, not from any infection.
Can primary immunodeficiency develop in adults?
Yes. Common Variable Immunodeficiency (CVID), the most frequently diagnosed symptomatic PID, often presents in the second or third decade of life. Adults with unexplained recurrent severe infections should be evaluated.
Is immunoglobulin replacement available in India?
Yes, IVIG is available in India and covered by some insurance policies. Access outside major cities remains limited. Your clinical immunologist can help navigate procurement and insurance authorisation.
My child keeps getting ear infections. Do they have PID?
Most children with recurrent ear infections have common causes — allergy, adenoid hypertrophy, anatomical factors, or childcare-related repeated exposure. A full assessment by a paediatrician is the first step. If four or more ear infections have occurred in a year alongside other warning signs, a clinical immunology referral is warranted.
Are PIDs hereditary? Should siblings be tested?
Many PIDs follow Mendelian inheritance patterns. If a child is diagnosed with a PID, genetic counselling and sibling evaluation are standard recommendations, depending on the specific diagnosis. The inheritance pattern (autosomal recessive, X-linked, autosomal dominant) determines the sibling risk.
This article is for educational purposes. It does not constitute medical advice and does not replace specialist evaluation. Dr. Keerthi Vardhan, MD (Internal Medicine), DM (Clinical Immunology & Rheumatology), Assistant Professor, NIMS Hospital, Hyderabad.