A National Survey of Hereditary Angioedema and Acquired C1 Inhibitor Deficiency in the United Kingdom

BACKGROUND

Detailed demographic data on people with hereditary angioedema (HAE) and acquired C1 inhibitor deficiency in the United Kingdom are relatively limited. Better demographic data would be beneficial in planning service provision, identifying areas of improvement, and improving care.

OBJECTIVE

To obtain more accurate data on the demographics of HAE and acquired C1 inhibitor deficiency in the United Kingdom, including treatment modalities and services available to patients.

METHODS

A survey was distributed to all centers in the United Kingdom that look after patients with HAE and acquired C1 inhibitor deficiency to collect these data.

RESULTS

The survey identified 1152 patients with HAE-1/2 (58% female and 92% type 1), 22 patients with HAE with normal C1 inhibitor, and 91 patients with acquired C1 inhibitor deficiency. Data were provided by 37 centers across the United Kingdom. This gives a minimum prevalence of 1:59,000 for HAE-1/2 and 1:734,000 for acquired C1 inhibitor deficiency in the United Kingdom. A total of 45% of patients with HAE were on long-term prophylaxis (LTP) with the most used medication being danazol (55% of all patients on LTP). Eighty-two percent of patients with HAE had a home supply of acute treatment with C1 inhibitor or icatibant. A total of 45% of patients had a supply of icatibant and 56% had a supply of C1 inhibitor at home.

CONCLUSIONS

Data obtained from the survey provide useful information about the demographics and treatment modalities used in HAE and acquired C1 inhibitor deficiency in the United Kingdom. These data are useful for planning service provision and improving services for these patients.

Outcomes following SARS-CoV-2 infection in patients with primary and secondary immunodeficiency in the UK

In March 2020, the United Kingdom Primary Immunodeficiency Network (UKPIN) established a registry of cases to collate the outcomes of individuals with PID and SID following SARS-CoV-2 infection and treatment. A total of 310 cases of SARS-CoV-2 infection in individuals with PID or SID have now been reported in the UK. The overall mortality within the cohort was 17.7% (n = 55/310). Individuals with CVID demonstrated an infection fatality rate (IFR) of 18.3% (n = 17/93), individuals with PID receiving IgRT had an IFR of 16.3% (n = 26/159) and individuals with SID, an IFR of 27.2% (n = 25/92). Individuals with PID and SID had higher inpatient mortality and died at a younger age than the general population. Increasing age, low pre-SARS-CoV-2 infection lymphocyte count and the presence of common co-morbidities increased the risk of mortality in PID. Access to specific COVID-19 treatments in this cohort was limited: only 22.9% (n = 33/144) of patients admitted to the hospital received dexamethasone, remdesivir, an anti-SARS-CoV-2 antibody-based therapeutic (e.g. REGN-COV2 or convalescent plasma) or tocilizumab as a monotherapy or in combination. Dexamethasone, remdesivir, and anti-SARS-CoV-2 antibody-based therapeutics appeared efficacious in PID and SID. Compared to the general population, individuals with PID or SID are at high risk of mortality following SARS-CoV-2 infection. Increasing age, low baseline lymphocyte count, and the presence of co-morbidities are additional risk factors for poor outcome in this cohort.

P15 An audit of the management of Behçet's disease in a tertiary referral centre against guidelines from EULAR and the National Centres of Excellence

Background

BD patients are managed equivalently by multiple medical specialties in our trust. Failure to switch from IV to s/c antiTNFalpha therapies was noted and our use of methotrexate, hydroxychloroquine and cyclophosphamide deviates from guidelines. Whether this effects outcome is unknown it but seems likely to be considered clinically useful. A national audit would determine if our management is an anomaly or in keeping with standard practice in the UK prompting review of our treatment algorithm.

Methods

Involved specialities provided details of BD patients in their care. Electronic case records from January 2009 to July 2019 were reviewed. Data were extracted using standard pro-forma classifying patients into 3 groups determined by their most severe manifestation: less severe (predominant musculoskeletal, mucocutaneous); ophthalmic (all eye disease) and severe disease (predominant CNS and vascular disease). Medication was assessed against guidelines for escalation and de-escalation protocols.

Results

50 patients (representing approximately 7% of the national BD population) were identified from 4 specialties (Table 1). 23 were female; 45 identified as White British. 26 were regularly reviewed by 2 or more specialties, 4 had discontinued follow up. 26/50 had used antiTNFalpha therapies and 9/50 had received IV cyclophosphamide. Adherence to guidelines was determined by specialty and disease severity (Table 1). The EULAR guideline was followed least well by Rheumatology; low rates of adherence to the national guideline reflected frequent use of methotrexate and hydroxychloroquine in the less severe group and failure to switch to from IV to sub-cutaneous antiTNFalpha therapies. Deviations from national and EULAR guidelines in the ‘severe’ category related to the first line use of IV cyclophosphamide for acute organ/sight threatening disease.

Conclusion

BD patients are managed equivalently by multiple medical specialties in our Trust. Failure to switch from IV to s/c antiTNFalpha therapies was noted and our use of methotrexate, hydroxychloroquine and cyclophosphamide deviates from guidelines. Whether this effects outcome is unknown it but seems likely to be considered clinically useful. A national audit would determine if our management is an anomaly or in keeping with standard practice in the UK prompting review of our treatment algorithm.

Disclosures

J. Weightman None. B. Griffiths None. R. Pandit None. C. Stroud None. A.D. Price None. A.R. Lorenzi None.

Respiratory Health and Related Quality of Life in Patients with Congenital Agammaglobulinemia in the Northern Region of the UK

Introduction

Patients with congenital agammaglobulinemia, characterized by a defect in B lymphocyte differentiation causing B alymphocytosis, require life-long IgG replacement. There is scant literature regarding the effectiveness of IgG treatment at preventing mucosal (particularly sinopulmonary tract) infection and whether current management adequately restores “normal” health and quality of life (QoL). We aimed to document infective episodes pre- and post-commencing IgG replacement, determine any change in lung function and structure and assess respiratory status and QoL in a cohort of patients treated in Newcastle.

Methods

Clinical data were extracted from medical records of 15 patients identified from the immunology database, focusing on infective episodes, serial chest CT and spirometry results. Thirteen patients completed a selection of standardized and validated questionnaires assessing physical health, respiratory health and QoL.

Results

Pediatric patients on IgG therapy suffered fewer infections per patient year (0.74) than adults (2.13). 6/14 patients showed deteriorating respiratory status despite adequate therapy. Health questionnaires revealed a significant burden of respiratory disease on a patient’s life.

Conclusion

Clinical data showed patients with congenital agammaglobulinemia receiving immunoglobulin therapy retained a higher than average infection rate, most of which affected mucosal barriers. Most patients self-reported worse respiratory symptoms, a lower respiratory-related QoL and a lower general health QoL relative to a healthy population. Most participants had progressive structural lung damage and decreased lung function. These results suggest that current management is not entirely effective at preventing deterioration of respiratory health or restoring QoL.

Practical management of antibiotic allergy in adults

This review looks at the main issues around immediate hypersensitivity and the role and limitations of testing. The majority of literature on antibiotic hypersensitivity relates to β-lactam antibiotics, mainly because of the heavy usage of this class of drugs. Concerns around cross-reactivity always worry clinicians, particularly in the emergency situation. Reasonable data now exist in relation to β-lactam antibiotics and derivatives, which enable appropriate risk management to be undertaken. The available literature for other classes of antibiotics is also discussed.

Falsely normal C4 in a case of acquired C1 esterase inhibitor deficiency

A 59-year-old lady presented with recurrent angioedema without urticaria. The clinical history and examination were consistent with an acquired C1 esterase deficiency secondary to lymphoproliferative disease. Despite a low C1 esterase level, the C4 level assayed by nephelometry on our automated analyser was normal. Analysis using different nephelometric analysers revealed consistently low C4, despite consistent normal readings in our analyser. Further investigation revealed an IgM-kappa paraprotein that seemed to interfere with both this and haematology coagulation assays. Splenic marginal zone lymphoma was confirmed on bone marrow biopsy. Monoclonal paraproteins may interfere with nephelometric, turbidimetric and immunological assays in a non-antibody-specific manner and should be considered when there are unusual or unexpected results, particularly in a patient with lymphoproliferative disease.

Direct measurements of urban OH reactivity during Nashville SOS in summer 1999

Emissions of volatile chemicals control the hydroxyl radical (OH), the atmosphere's main cleansing agent, and thus the production of secondary pollutants. Accounting for all of these chemicals can be difficult, especially in environments with mixed urban and forest emissions. The first direct measurements of the atmospheric OH reactivity, the inverse of the OH lifetime, were made as part of the Southern Oxidant Study (SOS) at Cornelia Fort Airpark in Nashville, TN in summer 1999. Measured OH reactivity was typically 11 s(-1). Measured OH reactivity was 1.4 times larger than OH reactivity calculated from the sum of the products of measured chemical concentrations and their OH reaction rate coefficients. This difference is statistically significant at the 1sigma uncertainty level of both the measurements and the calculations but not the 2sigma uncertainty level. Measured OH reactivity was 1.3 times larger than the OH reactivity from a model that uses measured ambient concentrations of volatile organic compounds (VOCs), NO, NO2, SO2, and CO. However, it was within approximately 10% of the OH reactivity from a model that includes hydrocarbon measurements made in a Nashville tunnel and scaled to the ambient CO at Cornelia Fort Airpark. These comparisons indicate that 30% of the OH reactivity in Nashville may come from short-lived highly reactive VOCs that are not usually measured in field intensive studies or by US EPA's Photochemical Assessment Monitoring Stations.

Randomised controlled trial of L-carnitine as a nutritional supplement in preterm infants

AIMS

To evaluate the effect of L-carnitine supplementation (25 mg/kg/d) on the growth and incidence of hypoglycaemia in preterm infants.

METHODS

A double blind, placebo controlled randomised trial, stratified for gestational age, was conducted of 86 preterm infants between 28 and 34 gestational weeks. The median gestational ages in the carnitine group and placebo groups were 30.7 weeks (range 28.0 to 33.6) and 31.4 weeks (range 28.0 to 33.9), respectively. The median birthweights were 1.557 kg (range 0.944 to 2.275) and 1.645 kg (range 0.885 to 2.545), respectively.

RESULTS

Mean plasma free carnitine concentrations were below values for normal term infants in both groups on day 1 (carnitine group 44.8 mumol/l, placebo group 25.5 mumol/l) in the placebo group on day 7 (50.7 mumol/l), but in neither group on days 14 and 28. Total, free, and acylcarnitine concentrations were significantly increased in both urine and blood in the L-carnitine group. There was no significant difference between the placebo and carnitine supplemented groups in growth rate, as assessed by weight, length, skinfold thickness and head circumference measurements, or in the incidence of episodes of hypoglycaemia.

CONCLUSION

The addition of carnitine as a nutritional supplement at a dose of 25 mg/kg/day did not improve growth in our group of preterm infants nor protect them from episodes of hypoglycaemia.

Shaping an atomic electron wave packet

We consider coherent control of the shape of an atomic electron's wavefunction using a train of short transform-limited laser pulses. This type of control is experimentally demonstrated by exciting with a train of three pulses and measuring the resulting quantum state distribution. We also present a general theory for control with a train of N pulses in the weak field limit and discuss the extension of this theory to the strong field limit.

Visualization of the core-scattering dynamics of Rydberg wave packets

We present classical and quantum studies of the scattering dynamics of Rydberg electron wave packets from the electronic core of alkali atoms. In quantum systems an ideal state for studying such effects is an angularly localized wavepacket in which the primary effect of the scattering is to cause precession. The scattering is enhanced by the application of an external dc electric field. We calculate and animate the field-induced dynamics of both hydrogenic and alkali wavepackets and compare them to classical atomic models. We end that in alkali systems the scattered wave function can be divided into two components: one whose nearly hydrogenic behavior is due to quantum interference near the core, and another which exhibits the orbital precession found in classical models of nonhydrogenic atoms.

Analysis of antibody-dependent cell-mediated cytotoxicity in autoimmune thyroid disease

There is no consensus on the role of antibody-dependent cell-mediated cytotoxicity (ADCC) in autoimmune thyroid disease; recent reports have suggested that antibodies mediating ADCC are found particularly in patients with primary myxoedema, occur less frequently in Hashimoto's thyroiditis and are absent in Graves' disease. Using an ADCC assay with a single source of effector and target cells, and expressing results as lytic units, we have found antibodies capable of mediating ADCC in 9 of 17 patients with primary myxoedema, 9 of 22 patients with Hashimoto's thyroiditis and 6 of 22 patients with Graves' disease. There was no significant difference between the groups in this distribution. Mean levels of ADCC activity were not significantly different comparing primary myxoedema and Hashimoto's thyroiditis patients, although levels were lower in Graves' disease patients compared to those with Hashimoto's thyroiditis (P < 0.05). There was no correlation between TPO antibodies (total IgG or IgG subclasses) measured by ELISA and ADCC activity. These results suggest that thyroid antigens besides TPO are involved in ADCC and that antibodies mediating ADCC are not restricted to subgroups of patients with autoimmune thyroid disease.

Surfactant content in children with inflammatory lung disease

OBJECTIVE

To determine surfactant profiles of tracheal secretions in mechanically ventilated children with respiratory failure secondary to bacterial pneumonia, viral pneumonitis, adult respiratory distress syndrome (ARDS), and cardiopulmonary bypass.

DESIGN

Prospective, cohort study.

SETTING

Tertiary, multidisciplinary, pediatric intensive care unit.

PATIENTS

One hundred twenty pediatric patients with respiratory failure requiring mechanical ventilation.

INTERVENTIONS

Routine tracheal aspirates were collected from children with bacterial pneumonia, viral pneumonitis, ARDS, postcardiopulmonary bypass, and a postsurgical control group. Samples were obtained on days 1, 2, 3, after every week of intubation and on the day of extubation.

MEASUREMENTS AND MAIN RESULTS

The tracheal aspirates were analyzed by high-performance liquid chromatography for lecithin/sphingomyelin rations and by enzyme-linked immunosorbent assay for surfactant proteins A and B. Lung compliance and the oxygenation index were measured on each day of sample collection. On day 1, patients with bacterial pneumonia, viral pneumonitis, and ARDS had decreased lecithin/sphingomyelin ration (p < .001), and those patients with bacterial pneumonia and viral pneumonitis had decreased surfactant protein A/protein concentration (p < .001). The lecithin/sphingomyelin ratios and surfactant protein A/protein concentration were significantly different among the groups (p < .001), with the bacterial pneumonia and viral pneumonitis groups having higher lecithin/sphingomyelin ratios and increased surfactant protein concentrations before extubation. Pulmonary compliance was lower and the oxygenation index was higher than controls (p < .001) in patients with bacterial pneumonia, viral pneumonitis, and ARDS. Pulmonary compliance was correlated weakly with lecithin/sphingomyelin ratio (r2 = .11, p < .001) and surfactant protein A/protein concentration (r2 = .03, p < .05). Surfactant protein B was similar in the diagnostic groups. Surfactant content in tracheal secretions from cardiopulmonary bypass patients was equivalent to controls.

CONCLUSION

Abnormal tracheal aspirate surfactant phospholipids and surfactant protein A were noted in children with bacterial pneumonia, viral pneumonitis, and ARDS, but not in children on cardiopulmonary bypass.

Relationship of exposure to human T lymphotropic virus and T helper cells in homosexual men

The detection of serum antibodies (Ab) against HTLV-III in individuals with AIDS and related symptoms (ARC) has unambiguously defined the association of the virus infection to AIDS. This study was done to determine the extent of exposure to HTLV-III in homosexual men by measuring (Ab) and relating it to the stage of disease and T cell subsets. We found Ab in 89.5% of the 492 men with the median titers by stage of disease being 1600 for symptom-free, 6400 for ARC or Kaposi's sarcoma, and 4800 for opportunistic infection (OI), respectively. There was no correlation between Ab titers and either absolute or relative T helper cells (T4+), even though these cells decreased with disease severity. More specifically, however, symptom free patients had a normal distribution of the helpers of suppression (T4+/Leu8+), whereas, in symptomatic men, there was a significant decrease suggesting that the target cell for the virus is a subpopulation of the T helper cell.

Behavioural correlates of an experimental hippocampal epileptiform syndrome in rats

Experiments are reported describing assessment of abnormal behaviour of rats in which a chronic epileptiform syndrome has been induced by the injection of tetanus toxin bilaterally into their hippocampi. The abnormal behaviour included hyper-reactivity to a novel environment, intermittent aggression on handling, and abnormally passive response to a strange rat introduced into their home cage. In animals with unilateral injection of toxin, electrical records from the hippocampi have been obtained. They illustrated bilaterally simultaneous discharges and also some independence between the two hippocampi. The discharges were accompanied by overt signs of complex partial seizures during the first few weeks of the syndrome but later occurred without motor signs. In this later stage the rats were somewhat resistant to the convulsant effects of pentylenetetrazol.