Increased Respiratory Viral Detection and Symptom Burden Among Patients with Primary Antibody Deficiency: Results from the BIPAD Study

Background Patients with primary antibody deficiency (PAD) are at increased risk of respiratory tract infections, but our understanding their nature and consequences remains limited. Objective To define the symptomatic microbial burden upper airway infection in adults PAD relative to age-matched controls. Methods Prospective 12-month observational study consisting a daily lower symptom score alongside fortnightly nasal swab molecular detection 19 pathogen targets. Results A total 44 patients 42 controls (including 34 household pairs) were recruited, providing more than 22,500 days scores 1,496 swabs. Swab questionnaire compliance exceeded 70%. At enrollment, 64% received prophylactic antibiotics, 34% prevalence bronchiectasis. On average, experienced exacerbations every 6 compared weeks for controls, associated significant impairment respiratory-specific quality-of-life scores. Viral detections worsening from participant's baseline. had odds ratio (OR) detection, particularly viral (OR, 2.73; 95% CI, 2.09-3.57), specifically human rhinovirus 3.60; 2.53-5.13) parainfluenza 3.06; 1.25-7.50). Haemophilus influenzae Streptococcus pneumoniae also frequent PAD. Young child exposure, IgM deficiency, presence bronchiectasis independent factors detection. Prophylactic antibiotic use was bacterial by PCR. Conclusions have frequency despite immunoglobulin replacement use. This highlights clear need future therapeutic trials population PAD, informs design.