Missed Opportunities to Diagnose Common Variable Immunodeficiency: a Population-Based Case-Control Study Identifying Indicator Diseases for Common Variable Immunodeficiency

PURPOSE

Delayed diagnosis of common variable immunodeficiency (CVID) remains a serious problem. We investigated whether some diseases diagnosed during out-patient visits or admission to hospitals could act as indicator conditions for CVID diagnosis.

METHODS

In this nested case-control study, we identified 128 cases diagnosed with CVID in Denmark (1999-2013) and 640 age-, gender-, and region-matched controls. We obtained data on diseases diagnosed at hospitals in the five years before CVID diagnosis from The National Hospital Registry. We grouped hospital diagnoses in 33 major disease categories and 210 subcategories. We used conditional logistic regression to calculate the odds ratios (OR) and 95% confidence intervals (CI) to estimate associations between disease exposure and subsequent CVID.

RESULTS

During the five years preceding a CVID diagnosis, cases had four times as many hospital contacts as the controls (p < 0.001). A diagnosis in 18 major disease categories showed a significant OR for subsequent diagnosis of CVID. The most substantial association with a subsequent CVID diagnosis was a diagnosis of lower respiratory tract infections (OR: 29.9; 95% CI: 14.2-63.2) and lung diseases (35.1; 15.0-82.5). We observed a similar association when we removed the last year before diagnosis from analysis and overall, in the years < 1, ≥ 1-3, and ≥ 3-5 before diagnosis, although the absolute number of exposures was small. Twenty-eight specific diseases displayed an at least 3-fold risk of subsequent CVID diagnosis.

CONCLUSION

Targeted screening for antibody deficiency in patients diagnosed with specific diseases associated with CVID may lead to earlier CVID diagnosis and treatment and thereby potentially reduced morbidity and mortality.

Evaluating Drug Prescription Patterns in Undiagnosed Common Variable Immunodeficiency Patients

OBJECTIVE

To compare the consumption of antibiotics (AB), systemic steroids, and inhaled bronchodilators/glucocorticoids in the 3 years preceding the diagnosis of common variable immunodeficiency (CVID) among CVID patients and matched controls and to estimate whether the level of consumption was associated with the risk of a subsequent CVID diagnosis.

METHODS

We conducted a nested case-control study, identifying all individuals (n=130 cases) diagnosed with CVID in Denmark (1994-2014) and 45 age- and sex-matched population controls per case (n=5850 controls) from national registers. Drug consumption was estimated as defined daily doses per person-year. We used conditional logistic regression to compute odds ratios and 95% confidence intervals.

RESULTS

In the 3 years preceding a CVID diagnosis, we observed more frequent and higher consumption of all three drug classes. The association between consumption and risk of subsequent CVID diagnosis was statistically significant for all drug classes. The association was stronger with higher consumption and shorter time to CVID diagnosis. The fraction of cases compared to the controls redeeming ≥1 prescription of the included drugs during the study period was higher for AB (97% vs 52%), systemic steroids (35% vs 7.4%), and inhaled bronchodilators/glucocorticoids (46% vs 11.7%) (p<0.001).

CONCLUSION

CVID patients have significantly higher use of AB, systemic steroids, and inhaled bronchodilators/glucocorticoids in the 3 years preceding CVID diagnosis than controls. Prescribing these drugs in primary healthcare could be an opportunity to consider (proactive) screening for CVID. Further studies are needed to identify optimal prescription cutoffs that could endorse its inclusion in public health policies.

How to Identify Common Variable Immunodeficiency Patients Earlier: General Practice Patterns

PURPOSE

Diagnostic delay is a major problem concerning common variable immunodeficiency (CVID). We aimed to determine the pattern of general practitioner (GP) consultations in individuals diagnosed with CVID within 3 years before the diagnosis and whether the risk of diagnosis was associated with the frequency of consultations or character of examinations.

METHODS

We conducted a nested case-control study, identifying 132 adult CVID patients and 5940 age- and gender-matched controls from national registers during 1997-2013. We used conditional logistic regression to calculate the odds ratios (OR) and 95% confidence intervals (95%CI).

RESULTS

The median number of consultations among individuals with CVID was more than twice that of the controls in all 3 years (3rd, 10; 2nd, 11.5; and 1st, 15.4 vs. 4). We found a statistically significant association between the number of consultations and the risk of a subsequent CVID diagnosis, independent of age and gender, but strongest in the individuals < 40 years. In the 3rd year before diagnosis, having 9-15 consultations compared with 1-4 was associated with an OR (95%CI) of 5.0 (2.3-10.9), 2.4 (1.1-5.4), and 1.3 (0.3-5.3) for those aged 18-40, 41-60, and > 60, respectively. Several examinations (i.e., blood tests for inflammation/infection and pulmonary function test) were associated with increased odds of a subsequent CVID diagnosis.

CONCLUSION

The risk of a CVID diagnosis was highly related to both the number of consultations and the character of examinations performed by the GP. CVID should be a differential diagnosis among patients with multiple consultations, especially in patients < 40 years old.

Identification and Characterization of a Nationwide Danish Adult Common Variable Immunodeficiency Cohort

In this study, we identified all adults living in Denmark diagnosed with common variable immunodeficiency (CVID) and characterized them according to clinical presentation and EUROclass classification. Using a retrospective, cross-sectional design, possible CVID patients were identified in the Danish National Patient Register and Centers in Denmark treating patients with primary immunodeficiencies. The CVID diagnosis was verified by review of medical records. One-hundred-seventy-nine adults with CVID were identified. This corresponds to a prevalence of 1:26,000. The median age at onset of symptoms was 29 years with no sex difference. The median age at diagnosis was 40 years. Males were diagnosed earlier with a peak in the fourth decade of life, whereas females were diagnosed later with a peak in the sixth decade. The median diagnostic delay was seven years. Recurrent sinopulmonary infections were seen in 92.7% of the patients. The prevalence of non-infectious complications was similar to that of previously reported cohorts: bronchiectasis (35.8%), splenomegaly (22.4%), lymphadenopathy (26.3%), granulomatous inflammation (3.9%) and idiopathic thrombocytopenic purpura (14.5%). Non-infectious complications were strongly associated with B cell phenotype, with all having a reduced number of isotype-switched memory B cells. One-hundred-seventy (95%) were treated with immunoglobulin replacement therapy, primarily administered subcutaneously. According to international guidelines, diagnostic evaluation was inadequate in most cases. This study emphasizes the need for improved diagnostic criteria and more awareness of CVID as a differential diagnosis. Diagnosis and management of CVID patients is a challenge requiring specialists with experience in the field of PID.

Rotavirus is frequent among adults hospitalised for acute gastroenteritis

INTRODUCTION

Rotavirus infection is the most common aetiology of acute gastroenteritis (AGE) among young children. In adults, diagnostics focus mainly on bacterial causes, though recent studies suggest that rotavirus is a frequent agent. The aim of this study was to examine the proportion of rotavirus in adults hospitalised with AGE and to identify possible predictors.

METHODS

During a 24-month period from 1 May 2010 adults (> 15 years) with AGE admitted to one of four hospitals in the Central Denmark Region were examined for rotavirus with VIKIA Rota-Adeno rapid test in addition to routine culture for bacterial pathogens.

RESULTS

A total of 265 adult patients were included. 9.4% tested positive for rotavirus. Enteropathogenic bacteria were found in 24.5% of the cases. In the majority of cases (62.3%), no pathogen was found. Overall, rotavirus was the second-most frequent pathogen, exceeded only by Campylobacter spp. Immunosuppression and a C-reactive protein (CRP) below 50 mg/l (0-8 mg/l) were associated with rotavirus. The seasonality of rotavirus differed markedly from that of bacterial gastroenteritis.

CONCLUSION

Rotavirus is the second-most frequently identified pathogen in adults hospitalised with AGE. Close contact to children or travel activity does not predict rotavirus gastroenteritis, but immunosuppression and a CRP below 50 mg/l do. The seasonality of rotavirus differs from that of bacterial gastroenteritis, making rotavirus the most frequently identified cause of AGE in adults admitted to hospital in the colder months.

FUNDING

The trial was funded by an unrestricted grant from Sanofi Pasteur MSD.

TRIAL REGISTRATION

not relevant.