Summary Selective immunoglobulin A (IgA) deficiency (IgAD) is the most common primary immunodeficiency in the western world. The aim of the study was to investigate the prevalence and clinical characteristics of Helicobacter pylori-infected dyspeptic patients with IgAD. Case samples were drawn from all subjects ≥ 12 years of age (n = 104729) who had undergone serum total IgA measurements during 2004–14 for any reason at Leumit Healthcare Services (Israel) and had serum total IgA < 0·07 g/l. The control group was comprised of a random sample of remaining patients with a case–control ratio of 10 controls for each case. The dyspeptic diseases were identified and retrieved from Leumit Health Care Services electronic database using specific ICD-9-CM diagnostic codes. The case group included 347 subjects and the control group 3470 subjects. There were no significant differences in the prevalence of patients with dyspepsia [84 (24·2%) versus 821 (23·6%) for cases and controls, respectively]. Additionally, there was no difference in a proportion of dyspeptic H. pylori-positive subjects [59 (17·1%) versus 524 (15·1%)] between the case and control groups. Only 59 (17%) among the 347 IgAD patients underwent gastroscopy. A significantly larger proportion of case subjects experienced several forms of gastritis [13 (61·9%) versus 38 (21·6%), P < 0·001), duodenal ulcers [seven (33·3%) versus 19 (10·8%); P = 0·01] and nodular lymphoid hyperplasia (NLH) [two (9·5%) versus none; P = 0·011]. IgAD is not associated with increased prevalence of H. pylori-associated dyspepsia; nevertheless, H. pylori-infected dyspeptic IgAD subjects experience more EGD-proved gastritis, duodenal ulcers and NLH.

Despite the established association between chronic idiopathic/spontaneous urticaria (CIU) and presence of antinuclear antibodies (ANAs), the prevalence of autoimmune comorbidities in this population has not been analyzed. Here, we aim to identify clinical and laboratory manifestations associated with ANA-positive CIU. ANA-positive patients were identified via electronic data capture from the electronic patient record database of Leumit Health care Services (LHS) of Israel. Patient characteristics, medical histories, and details of diagnostic workup, medical treatment, and follow-up were retrieved by performing a chart review of electronic patient records (EPRs). The prevalence of target diseases among ANA(+) CIU(+), ANA(+) CIU(-), and ANA(-) CIU(+) patients was calculated. A total of 91 ANA(+) CIU(+), 3131 ANA(+) CIU(-), and 478 ANA(-) CIU(+) patients were identified. The ANA(+) CIU(+) group was characterized by higher prevalence of Sjögren's syndrome (SS)-A 52 antibodies (Ab) (7.7% versus 2.4%; p = 0.008), SS-A 60 Ab (11% versus 2.8%; p = < 0.001), and SS-B Ab (14.3% versus 3.2%; p < 0.001), compared with ANA(-) CIU(+) group. Additionally, ANA(+) CIU(+) patients were more likely to be diagnosed with thyroid autoimmune diseases, higher C-reactive protein (6.4 ± 10.3 versus 4.1 ± 8.8 mg/L; p = 0.027), and more profound basopenia (0.04 ± 0.09 versus 0.15 ± 0.11 cell/mm(3); p < 0.001) than ANA(-) CIU patients. More ANA(+) CIU(+) patients were resistant to four-fold standard licensed doses of antihistamines than ANA(-) CIU(+) patients [11 (12.1%) versus 29 (6.1%); p = 0.046]. ANA-positive CIU is characterized by higher prevalence of SS-A 52, SS-A 60, and SS-B antibodies and poorer clinical response to antihistamine medications.