Rituximab to treat prolidase deficiency due to a novel pathogenic copy number variation in PEPD

Prolidase deficiency (PD) is a rare autosomal recessive inborn error of immunity caused by biallelic homozygous or compound heterozygous loss-of-function mutations in PEPD, the gene that encodes prolidase. PD typically manifests with variable dysmorphic features, chronic cutaneous ulcers, recurrent infections and autoimmune features, including systemic lupus erythematosus. So far, there is no consensus regarding treatment of PD and its autoimmune manifestations. Here, we present a 28-year-old female patient with PD due to a novel homozygous intragenic deletion in PEPD, diagnosed at the age of 6 years and 7 months with an undifferentiated connective tissue disease that, apart from its very early onset, would be consistent with the diagnosis of Sjögren's syndrome. Steroids and diverse conventional synthetic disease-modifying antirheumatic drugs failed to control PD-associated vasculitis and mucocutaneous ulcerations and led to infectious complications, including cytomegalovirus colitis. Introduction of rituximab (RTX) treatment in this patient led to sustained recession of mucocutaneous ulceration, enabling tapering of steroids. High interleukin-1β (IL-1β) production by this patient's monocytes, together with the detection of both IL-1β and interleukin-18 (IL-18) in her serum, suggest enhanced inflammasome activation in PD, whereas the therapeutic efficacy of RTX implies a role for CD20 positive B cells in the complex immunopathogenesis of PD.

Survival in patients with congenital heart disease and down syndrome

Background

Increasing survivorship among patients with congenital heart disease (CHD) has been reported during the past decades. However, a number of patients with CHD have an associated Down syndrome diagnosis and the long-term prognosis is still debated.

Purpose

The aim of the present study was to estimate the mortality risk in CHD patients with Down syndrome compared to a matched control population without CHD.

Methods

We linked data from the Swedish National Patient Register and Cause of Death Register to identify all CHD patients born between January 1970 and December 2017. Then we identified all CHD patients with Down syndrome. Each CHD patient with Down syndrome was matched for sex and birth year with eight controls without CHD or Down syndrome from the Total Population Register. A Cox proportional regression model was used to estimate the mortality risk and Kaplan Meier for survival analysis.

Results

In total, 3,285 patients with CHD and Down syndrome and 26,128 matched controls were identified. During a mean follow-up of 16.0 (±12.6) years, 558 CHD patients (17%) with Down syndrome, and 198 controls (0.76%) died. CHD patients with Down syndrome had 25.1 times higher risk of mortality (Hazard ratio 25.1, 95%, confidence interval (CI) 21.3–29.5) compared with controls. Patients with the most complex CHD were found to have the highest mortality risk (Hazard ratio 32.3, 95% CI 26.1–39.9). A decrease in risk of mortality during the first year of life was found between the two birth periods, risk of mortality was 46.8 (CI 29.5–74.0) in 1970–1989 and 17.7 (CI 12.8–24.42) 1990–2017. In addition, the mortality risk was two times (95% CI 1.94–2.31) higher for CHD patients with Down syndrome when compared to CHD patients without Down syndrome.

Conclusion

The risk of mortality among CHD patients with Down syndrome was 25 times higher compared to controls without CHD or Down syndrome. The highest risk of mortality was found in patients with complex CHD. The survivorship rate was exponentially increased in CHD patients with Down syndrome that were born after 1990, determining the modern era of congenital heart care.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swedish state under an agreement between the Swedish Government and county Councils (ALF)

Heart failure and long-term prognosis in patients with congenital heart disease: a nationwide, register-based cohort study

Introduction

Heart failure (HF) is associated with high morbidity and severe prognosis. The aim of this study was to investigate the risk of HF in patients with congenital heart disease (CHD) and to determine the prognosis after HF diagnoses in patients with CHD compared to HF controls without CHD.

Methods

We identified 89,532 patients with CHD born between 1930 and 2017 from the National Patient Register in Sweden and matched with 10 controls without CHD by gender and birth year from the National Population Register. The study population was followed-up until 2017, through the Swedish Patient Register and Cause of Death Register.

Results

Altogether, 7,013 (7.8%) patients with CHD and 9,681 (1.1%) controls developed HF. The overall incidence rate of HF was 31.6 per 104 person-years in patients with CHD and 4.0 per 104 person-years in controls. The mean age for HF diagnoses was 40.3 (± 28.8) in patients with CHD and 66.4 (± 13.6) for controls. The risk for developing HF was significantly higher in complex than non-complex CHD lesion groups, HR 28.7 (26.5–31.0) and HR 6.9 (6.7–7.2) respectively. Mortality incidence rate was twice as high in controls with HF compared to CHD with HF (IR 9.7 (9.4–10.0) and 4.74 (4.6–4.9), respectively). The mortality incidence was higher within all age groups except for 18–39 years and there was no difference between complex and non complex lesions

Conclusion

One out of thirteen CHD patients will develop HF. The highest risk for HF is within CHD patients with complex lesions. CHD patients develops HF at a considerably younger age, reflecting their slightly better prognosis after development of HF compared to controls with HF.

Funding Acknowledgement

Type of funding sources: None.

Risk predictors and outcomes of infective endocarditis among adult patients with congenital heart disease

Background

Infective endocarditis (IE) is a serious disease associated with increased morbidity and mortality. Patients with adult congenital heart disease (ACHD) have been reported to be at a particularly increased risk of infective endocarditis (IE).

Purpose

To investigate the risk predictors of IE, and the long-term risk of IE among ACHD patients aged 18–65 years, compared with matched controls without ACHD, in a nationwide setting.

Methods

All patients with ACHD in Sweden born in years 1952–1999 and who survived until 18 years of age were followed in the National Patient Register and Cause of Death Register until year 2017. For each case of ACHD, approximately ten controls without ACHD were randomly selected from the Total Population Register and matched by birth year and sex. The study population was followed from 18 years of age and until a first time diagnosis of IE, death or end of study. Both comorbidities and occurrence of ACHD related surgery were collected from 1970 and onwards. Cox proportional hazard models were used to predict the risk of IE.

Results

Altogether, 36,189 ACHD patients and 403,962 controls without ACHD were included. A total of 706 (1.95%) ACHD patients and 147 (0.04%) controls developed IE during a median follow-up of 15.5 (interquartile range (IQR) 6.9–28.5) years (ACHD) and 15.5 (IQR 7.5–28.5) years (controls). ACHD patients were somewhat younger at age of IE diagnosis compared with controls, median age 33.9 (IQR 25.4–44.1) years in ACHD vs 39.8 (IQR 30.6–52.0) years in controls. The overall risk of IE was markedly higher among ACHD patients compared with controls, with a hazard ratio (HR) of 54.8 (95% confidence interval (CI), 45.9–65.5). More than one third of the ACHD patients with IE (n=272, 38.5%) had undergone any kind of previous congenital heart surgery whereof 122 (44.9%) had undergone valve replacement (mechanical/biological) prior to IE.

In ACHD patients, the most important risk predictors for IE were ACHD related cardiac surgery and valve replacement surgery, HR 117 (95% CI 93.0–148) and HR 74.8 (95% CI 56.4–99.2), respectively. Diabetes mellitus, previous ischemic stroke and presence of an intracardiac electronic device also predicted the risk of IE, however, they were less important predictors (diabetes: HR 1.69, 95% CI 1.01–2.82, ischemic stroke: HR 1.75, 95% CI 1.21–2.52, electronic device: HR 1.59, 95% CI 1.05–2.39).

Conclusion

The risk of developing IE was found to be almost 55 times higher in patients with ACHD aged 18–65 years compared with matched controls. Previous ACHD related surgery and valve replacement were the most significant risk predictors. These results underscore the need of continuous clinical follow-up as well as the need of further research to prevent this serious complication of ACHD.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): The work was supported by grants from the Swedish state under an agreement between the Swedish government and country councils, the ALF-agreement (grant numbers 236611 and 917361); and the Swedish Heart-Lung Foundation (grant number: 20180644 and 20200521).

Ischemic stroke in patients with congenital heart disease and atrial fibrillation

Background

Atrial fibrillation (AF) is one of the most common arrhythmias in patients with congenital heart disease (CHD). The risk of developing AF is more than 20 times higher in patients with CHD compared with non-CHD controls. However, while it is known that young non-CHD patients with AF have a low risk for ischemic stroke (IS), little is known about the risk for IS young CHD patients with AF.

Purpose

To investigate the risk of developing IS in younger patients with CHD and AF compared to non-CHD control patients with AF.

Method

Using data from the National Swedish Patient Register and Cause of Death register, all CHD and born in Sweden between 1970 and 2017 with history of AF were identified. The Swedish total population register was used to identify age and sex matched controls. Among the matched controls, non-CHD patients AF were identified and used as reference group. CHD and non-CHD patients were followed from onset of AF until index IS, death or end of study (31st December 2017). Cox proportional hazard regression model with hazard ratio (HR) and 95% confidence interval (CI) was used to estimate the risk of IS in CHD patients with AF compared with non-CHD controls with AF.

Results

A total of 951 CHD with AF and 606 non-CHD controls with AF were identified. With ages ranging from 0 to 47 years, the median age was 25.6 and 30.7 years for CHD and non-CHD respectively. In patients with CHD and AF, 2.9% of patients (n=28) developed IS during follow up (mean follow up 34 years, SD ± 11.2), compared 0.5% (n=3) in non-CHD controls with AF (mean follow up 37 years, SD ± 9.5 years). The unadjusted HR for IS in CHD patients with AF compared with non-CHD controls with AF was 4.61 (95% CI1.39–15.25). When adjusted for age, sex, hypertension and heart failure, the risk of IS was more than five times higher (HR 5.16, 95% CI 1.52–17.46) in CHD patients compared with non-CHD patients. The adjusted HR for developing IS in non-complex CHD with AF compared with matched controls was 4.56 (95% CI 1.00–20.79). For patients born 1970–1989 the HR of IS was 7.35 (95% CI 1.70–31.75).

Conclusion

In this nationwide, register-based cohort study, the absolute number of IS among younger CHD patients with AF was relatively low. However, the risk for developing IS was more than 5 times higher compared to non-CHD patients with AF; highlighting the need of stroke score models in younger population, particularly to CHD patients.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swedish state under an agreement between the Swedish government and city Councils

Long-term mortality from birth in individuals with and without isolated congenital aortic stenosis: a nationwide, register-based cohort study

Background

Congenital aortic valve stenosis (CAVS) accounts for almost 5% of congenital heart defects. Increased survival has been reported in patients with complex congenital heart defects over the last decade. However, data on the long-term outcomes of simple defects such as in isolated CAVS, are still limited.

Purpose

The present study aimed to investigate the risk of mortality in patients with isolated CAVS over the last half century in Sweden.

Methods

We used data from the Swedish National Patient and Cause of Death Register to identify patients with isolated CAVS born between 1970 and 2017. Each CAVS was matched with 10 controls without congenital heart disease from the Total Population Register, according to sex and birth year. The maximal follow-up time was from birth up to 47.5 years of age. We estimated mortality rates for cases and controls, and the 95% confidence interval (CI) of their ratio. Kaplan-Meier curves were used to estimate the survival for cases and controls under the follow-up.

Results

A total of 1,258 patients with isolated CAVS and 12,550 matched controls were included in the study. The median follow-up was 24.5 years (interquartile range (IQR):18.0) for cases and 25.5 years (IQR: 17.6) for controls respectively. The overall risk of mortality was more than three times higher for patients with isolated CAVS, compared with matched controls, hazard ratio (HR) 3.1 (95%, CI 2.1–4.5). Survival at 47.5 years of age was 94.1% for cases and 97.3% for controls. Within the first year of life, the mortality risk in patients with isolated CAVS was more than 19 times higher (95%, CI 8.8–43.6) than controls. By contrast, when diagnosed with isolated CAVS above the age of 10 years, the risk of mortality was 2.1 times higher (95%, CI 1.1–3.5) compared to controls.

Conclusions

The mortality in patients with isolated CAVS was more than three times higher compared with matched controls. The highest mortality was found in patients with a diagnosis of isolated CAVS diagnosed within the first year after birth, verifying the critical form of the disease. Furthermore, patients diagnosed with isolated CAVS later in life (hence clinically assumed as a mild form of valvulopathy) have a mortality risk twice as high as controls, highlighting the need for follow-up and lifetime management, even in the mild forms of valvulopathies.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swedish state under an agreement between the Swedish Government and county Councils (ALF)

Chronic kidney disease in patients with congenital heart disease – a nationwide, register-based cohort study

Aims

To investigate the risk of chronic kidney disease (CKD) in young patients with congenital heart disease (CHD) (age 0–47 years) compared with age- and sex-matched controls without CHD.

Methods and results

Using data from the Swedish National Patient Register and the Cause of Death Register, 71,936 patients with CHD (50.2% male) born between 1970 and 2017 were identified. Each patient with CHD was matched by sex and age to 10 controls without CHD (n = 714,457). Follow-up data were collected for patients with CHD and controls until 2017. During a median follow-up of 13.5 (5.8; 25.5) years, 379 (0.5%) patients with CHD and 679 (0.1%) controls developed CKD. The risk of CKD was 6.4 times higher in patients with CHD than controls [95% confidence interval (CI): 5.65–7.27] and was highest in patients with severe non-conotruncal defects [hazard ratio (HR): 11.31; 95% CI: 7.37–17.36]. Compared with matched controls, the absolute and relative risks of CKD were greater for CHD patients born between 1997 and 2017 (HR: 9.98; 95% CI: 8.05–13.37) (incidence 39.5 per 100 000 person-years). The risk of CKD remained significantly higher after adjusting for hypertension, acute kidney injury, and diabetes mellitus (HR: 4.37; 95% CI: 3.83–5.00).

Conclusion

Although the absolute risk of CKD in young patients with CHD is relatively low, patients with CHD are six times more likely to develop CKD than non-CHD controls up to the age of 47 years. Further data are needed to inform guidelines on the prevention and follow-up of CKD in CHD patients.

Risk of myocardial infarction in middle aged and older patients with coarctation of the aorta

Introduction

Previous case-control studies have compared the risk of coronary artery disease/myocardial infarction (MI) in patients with coarctation of the aorta (CoA) with other congenital heart disease diagnoses, however, these studies have only included younger patients in their 20s and 30s, not older patients. As the atherosclerotic burden is increasing with increasing age, it is important to study the risk of MI in older patients (from early middle age and older) with CoA.

Purpose

The aim of our study was to investigate the risk of MI in older patients (≥40 years) with CoA, and to compare this risk with the risk in patients of the same age with ventricular septal defects (VSD), the most common congenital heart condition.

Methods

We used data from the Swedish National Patient Registry (NPR) to identify all patients alive at 40 years of age with a diagnosis of CoA or VSD, born during the period 1930–1970. The follow-up through the NPR and the Cause-specific Death Registry started in January 1970 and went on until December 2017.

Results

Altogether 1204 patients with CoA and 2079 patients with VSD were identified in the registers, and in total, 97 (8.1%) patients with CoA and 162 (7.8%) patients with VSD developed an MI during follow up. Mean follow up time was 20.6±10.3 years in CoA patients and 21.3±10.9 in the VSD group. The risk of MI was similar in CoA compared with VSD patients (HR 1.1, 95% confidence interval 0.9–1.5, p=0.3) Median age at MI was similar in CoA patients and in VSD patients; in CoA 59.8 years (range 40.1–87.5), in VSD 61.2 (range 40.2–87.5), p=0.3. Hypertension (diagnosed before MI or within a year after MI) was more common in CoA patients with an MI (58.8%) compared with VSD patients (37.7%), however, prevalence of diabetes mellitus and hyperlipidemia was similar in both patient groups (18.6% and 21.6% in CoA respectively, compared to 17.9% and 22.8% in VSD group). After adjustment for hypertension, diabetes mellitus and hyperlipidemia, the risk of MI remained similar in patients with CoA and VSD (hazard ratio 1.1, 95% confidence interval 0.8–1.4, p=0.5).

Conclusion

In this large nationwide study, we found that in older patients with CoA (median age at MI 60 years, range 40–88 years) the risk of MI was not increased and similar to that of patients with VSD with similar age at MI. Adjustment for hypertension, diabetes mellitus and hyperlipidemia did not modify this finding which suggests that patients with CoA do not have an increased risk of MI, compared to patients with VSD.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): This work was funded by the Swedish state under an agreement between the Swedish government and county councils, the ALF agreement (Grant number: 236611) and the Swedish Heart-Lung Foundation (Grant Number: 20090724).

Risk of ischemic stroke in adult patients with congenital heart disease

Introduction

With an increasing proportion of adults with congenital heart disease (CHD) surviving into middle age and beyond, CHD patients will be at increased risk of acquired cardiovascular conditions, such as ischemic stroke. Compared to controls, patients with CHD have a higher prevalence of arrhythmias, persistent shunts enabling paradoxical embolization, heart failure, mechanical valves as well as potentially hypercoagulable states, all of which can further increase the risk of stroke.

Purpose

The aim of our study was to investigate the risk of developing ischemic stroke in adults with CHD in Sweden compared to controls from the general population.

Methods

We used data from the Swedish National Patient and Cause of Death registries to identify all CHD patients ≥18 years of age, born during the period 1930–1998, with a first time diagnosis of ischemic stroke. Follow-up started in January 1970 and went on until December 2017. Approximately ten controls matched for age and sex were randomly selected from the general population for each patient with CHD. CHD diagnoses were classified into six lesion groups according to a previously published hierarchical classification system.

Results

In total, 43,110 patients with CHD and 474,267 controls were included in the study (51.4% men) and mean follow up time was 25.4±18.4 years. Patients with CHD had a 6 times higher risk of developing an ischemic stroke compared with controls (hazard ratio 6.0, 95% confidence interval 5.8–6.2, p≤0.001), with altogether 8.8% (n=3785) of CHD patients developing ischemic stroke compared with 1.6% (n=7516) of controls. Ischemic stroke was more common in all CHD lesion groups; however, patients with atrial septal defects/patent foramen ovale had the highest incidence rate of ischemic stroke with an incidence rate of 76.1 events/10,000 patient years compared with 8.7 in controls. Patients with CHD and ischemic stroke had markedly less hypertension, diabetes mellitus and hypercholesterolemia, compared with controls (7.1%, 2.0%, 2.9% respectively in CHD patients, compared with 19.6%, 6.6%, 5.3%, in controls, p≤0.001 for all). In addition, atrial fibrillation and heart failure were only slightly more common in CHD patients with ischemic stroke compared to controls (atrial fibrillation: 12.0% in CHD vs 10.4% in controls, p=0.01; heart failure: 8.7% in CHD vs 7.3% in controls, p=0.009).

Conclusion

In this large nationwide study, we found that the risk of ischemic stroke in adult patients with CHD was six times higher than in controls, despite a lower prevalence of common risk factors for stroke such as hypertension, diabetes mellitus and hypercholesterolemia. In addition, atrial fibrillation and heart failure were only slightly more common in CHD patients compared with controls. This implies that the etiology of ischemic stroke might be different in CHD patients compared with controls.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): This work was funded by the Swedish state under an agreement between the Swedish government and county councils, the ALF agreement (Grant number: 236611) and the Swedish Heart-Lung Foundation (Grant Number: 20090724).

Implant-based direction of magnetic nanoporous silica nanoparticles - influence of macrophage depletion and infection

Implant associated infections are still key problem in surgery. In the present study, the combination of a magnetic implant with administered magnetic nanoporous silica nanoparticles as potential drug carriers was examined in mice in dependence of local infection and macrophages as influencing factors. Four groups of mice (with and without implant infection and with and without macrophage depletion) received a magnet on the left and a titanium control on the right hind leg. Then, fluorescent nanoparticles were administered and particle accumulations at implant surfaces and in inner organs as well as local tissue reactions were analyzed. Magnetic nanoparticles could be found at the surfaces of magnetic implants in different amounts depending on the treatment groups and only rarely at titanium surfaces. Different interactions of magnetic implants, particles, infection and surrounding tissues occurred. The general principle of targeted accumulation of magnetic nanoparticles could be proven.

Progressive Immunodeficiency with Gradual Depletion of B and CD4⁺ T Cells in Immunodeficiency, Centromeric Instability and Facial Anomalies Syndrome 2 (ICF2)

Immunodeficiency, centromeric instability and facial anomalies syndrome 2 (ICF2) is a rare autosomal recessive primary immunodeficiency disorder. So far, 27 patients have been reported. Here, we present three siblings with ICF2 due to a homozygous ZBTB24 gene mutation (c.1222 T>G, p. (Cys408Gly)). Immune deficiency in these patients ranged from late-onset combined immunodeficiency (CID) with severe respiratory tract infections and recurrent shingles to asymptomatic selective antibody deficiency. Evident clinical heterogeneity manifested despite a common genetic background, suggesting the pathogenic relevance of epigenetic modification. Immunological follow-up reveals a previously unidentified gradual depletion of B and CD4⁺ T cells in all three presented patients with transition of a common variable immunodeficiency (CVID)-like disease to late-onset-CID in one of them. Considering all previously published cases with ICF2, we identify inadequate antibody responses to vaccines and reduction in CD27⁺ memory B cells as prevalent immunological traits. High mortality among ICF2 patients (20%) together with the progressive course of immunodeficiency suggest that hematopoietic stem cell transplantation (HSCT) should be considered as a treatment option in due time.