Richard Herriot

Clinical spectrum and features of activated phosphoinositide 3-kinase δ syndrome: A large patient cohort study

Background: Activated phosphoinositide 3‐kinase &dgr; syndrome (APDS) is a recently described combined immunodeficiency resulting from gain‐of‐function mutations in PIK3CD, the gene encoding the catalytic subunit of phosphoinositide 3‐kinase &dgr; (PI3K&dgr;). Objective: We sought to review the clinical, immunologic, histopathologic, and radiologic features of APDS in a large genetically defined international cohort. Methods: We applied a clinical questionnaire and performed review of medical notes, radiology, histopathology, and laboratory investigations of 53 patients with APDS. Results: Recurrent sinopulmonary infections (98%) and nonneoplastic lymphoproliferation (75%) were common, often from childhood. Other significant complications included herpesvirus infections (49%), autoinflammatory disease (34%), and lymphoma (13%). Unexpectedly, neurodevelopmental delay occurred in 19% of the cohort, suggesting a role for PI3K&dgr; in the central nervous system; consistent with this, PI3K&dgr; is broadly expressed in the developing murine central nervous system. Thoracic imaging revealed high rates of mosaic attenuation (90%) and bronchiectasis (60%). Increased IgM levels (78%), IgG deficiency (43%), and CD4 lymphopenia (84%) were significant immunologic features. No immunologic marker reliably predicted clinical severity, which ranged from asymptomatic to death in early childhood. The majority of patients received immunoglobulin replacement and antibiotic prophylaxis, and 5 patients underwent hematopoietic stem cell transplantation. Five patients died from complications of APDS. Conclusion: APDS is a combined immunodeficiency with multiple clinical manifestations, many with incomplete penetrance and others with variable expressivity. The severity of complications in some patients supports consideration of hematopoietic stem cell transplantation for severe childhood disease. Clinical trials of selective PI3K&dgr; inhibitors offer new prospects for APDS treatment.

The United Kingdom Primary Immune Deficiency (UKPID) Registry: report of the first 4 years' activity 2008-2012

This report summarizes the establishment of the first national online registry of primary immune deficency in the United Kingdom, the United Kingdom Primary Immunodeficiency (UKPID Registry). This UKPID Registry is based on the European Society for Immune Deficiency (ESID) registry platform, hosted on servers at the Royal Free site of University College, London. It is accessible to users through the website of the United Kingdom Primary Immunodeficiency Network (www.ukpin.org.uk). Twenty‐seven centres in the United Kingdom are actively contributing data, with an additional nine centres completing their ethical and governance approvals to participate. This indicates that 36 of 38 (95%) of recognized centres in the United Kingdom have engaged with this project. To date, 2229 patients have been enrolled, with a notable increasing rate of recruitment in the past 12 months. Data are presented on the range of diagnoses recorded, estimated minimum disease prevalence, geographical distribution of patients across the United Kingdom, age at presentation, diagnostic delay, treatment modalities used and evidence of their monitoring and effectiveness.

Towards a safety net for management of 22q11.2 deletion syndrome: guidelines for our times.

The commonest autosomal deletion, 22q11.2 deletion syndrome (22q11DS) is a multisystem disorder varying greatly in severity and age of identification between affected individuals. Holistic care is best served by a multidisciplinary team, with an anticipatory approach. Priorities tend to change with age, from feeding difficulties, infections and surgery of congenital abnormalities particularly of the heart and velopharynx in infancy and early childhood to longer-term communication, learning, behavioural and mental health difficulties best served by evaluation at intervals to consider and initiate management. Regular monitoring of growth, endocrine status, haematological and immune function to enable early intervention helps in maintaining health. Conclusion: Guidelines to best practice management of 22q11DS based on a literature review and consensus have been developed by a national group of professionals with consideration of the limitations of available medical and educational resources.

Serum Trough IgG level and Annual Intravenous Immunoglobulin Dose Are Not Related to Body Size in Patients on Regular Replacement Therapy

Therapeutic regimens of intravenous immunoglobulin are currently based on actual body weight. The relationship between immunoglobulin dose and serum IgG level in relation to body size was retrospectively explored in patients on replacement therapy. Data were collected as part of a national audit on immunoglobulin therapy in patients with common variable immunodeficiency. 107 patients received immunoglobulin titrated to optimum effect. Correlations were sought between body mass index, trough IgG levels, infusion frequency and total annual dose. The mean (±SD) trough IgG level was 8.4±1.6 g/L and annual immunoglobulin dose received was 456.8±129.4 g. There was no relationship between annual dose and trough IgG level, regardless of infusion frequency, or adjustment for weight or body mass index. These results support the clinical practice of immunoglobulin prescription by clinical outcome rather than fixed dose by body weight. Future studies exploring immunoglobulin efficacy should include treatment arms with dosages based on both ideal and actual body weight, as ideal body weight-based prescribing would save significant amounts of product.

T cell participation in autoreactivity to NC16a epitopes in bullous pemphigoid.

Bullous pemphigoid is a blistering skin disease characterized by autoantibodies against the NC16a domain of bullous pemphigoid 180. This study was performed to characterize and map the fine specificity of T cell responses to NC16a. Peripheral blood mononuclear cells (PBMC) from a total of 28 bullous pemphigoid patients and 14 matched controls were tested for proliferative and cytokine responses to recombinant NC16a and a complete panel of 21 overlapping peptides spanning this region of BP180. Proliferative responses to NC16A and the peptide panel in the patients with active disease were similar in frequency and magnitude to those in healthy donors, and included late responses typical of naive cells in approximately 60% of each group. Interleukin (IL)‐4 responses were slightly stronger for six peptides, and significantly stronger for Nc16a, in patients than in controls. Factor analysis identified factors that separate responses to the peptide panel discretely into IL‐4, T helper type 2 (Th2) pattern, interferon (IFN)‐γ, Th1 pattern and IL‐10 or transforming growth factor [TGF‐β, regulatory T cell (Treg)] pattern. Factors segregating IL‐10 versus IFN‐γ were predicted by active blistering or remission, and TGF‐β or IL‐10 versus IFN‐γ by age. Finally, we confirmed a significant up‐regulation of IgE responses to BP180 in the patients with pemphigoid. This shows the complexity of T cell phenotype and fine autoreactive specificity in responses to NC16A, in patients and in normal controls. Important disease‐associated factors determine the balance of cytokine responses. Of these, specific IL‐4 and IgE responses show the strongest associations with pemphigoid, pointing to an important contribution by Th2 cytokines to pathogenesis.

Bronchiectasis and deteriorating lung function in agammaglobulinemia despite immunoglobulin replacement therapy

Immunoglobulin replacement therapy enhances survival and reduces infection risk in patients with agammaglobulinaemia. We hypothesized that despite regular immunoglobulin therapy, some patients will experience ongoing respiratory infections and develop progressive bronchiectasis with deteriorating lung function. One hundred and thirty‐nine (70%) of 199 patients aged 1–80 years from nine cities in the United Kingdom with agammaglobulinaemia currently listed on the UK Primary Immune Deficiency (UKPID) registry were recruited into this retrospective case study and their clinical and laboratory features analysed; 94% were male, 78% of whom had Bruton tyrosine kinase (BTK) gene mutations. All patients were on immunoglobulin replacement therapy and 52% had commenced therapy by the time they were 2 years old. Sixty per cent were also taking prophylactic oral antibiotics; 56% of patients had radiological evidence of bronchiectasis, which developed between the ages of 7 and 45 years. Multivariate analysis showed that three factors were associated significantly with bronchiectasis: reaching 18 years old [relative risk (RR) = 14·2, 95% confidence interval (CI) = 2·7–74·6], history of pneumonia (RR = 3·9, 95% CI = 1·1–13·8) and intravenous immunoglobulin (IVIG) rather than subcutaneous immunoglobulin (SCIG) = (RR = 3·5, 95% CI = 1·2–10·1), while starting immunoglobulin replacement after reaching 2 years of age, gender and recent serum IgG concentration were not associated significantly. Independent of age, patients with bronchiectasis had significantly poorer lung function [predicted forced expiratory volume in 1 s 74% (50–91)] than those without this complication [92% (84–101)] (P < 0·001). We conclude that despite immunoglobulin replacement therapy, many patients with agammaglobulinaemia can develop chronic lung disease and progressive impairment of lung function.

Misdiagnosis of common variable immune deficiency

We present details of a man who was originally diagnosed with sarcoidosis, based on a combination of nodal granulomatous inflammation and radiology confirming bilateral hilar lymphadenopathy with pulmonary infiltrates. The patient subsequently developed splenomegaly and idiopathic thrombocytopenic purpura (ITP) and, latterly, a severe cavitating pneumonia. Serum immunoglobulins were checked, confirming panhypogammaglobulinaemia, and his diagnosis was revised to common variable immune deficiency (CVID). CVID is a heterogeneous condition, which can mimic sarcoidosis with granulomatous organ involvement and is commonly complicated by autoimmune disorders, including ITP. Prompt recognition is important to allow early introduction of immunoglobulin replacement therapy to decrease infection frequency, reduce development of secondary disease complications and retard progression of tissue damage. Given the potential for misdiagnosis and delay in recognition of CVID, serum immunoglobulin measurement should be a first-line investigation in patients with suspected sarcoidosis, even if the presentation is ‘typical’. Current international sarcoidosis guidelines should be revised accordingly.

The United Kingdom Primary Immune Deficiency (UKPID) Registry 2012 to 2017

This is the second report of the United Kingdom Primary Immunodeficiency (UKPID) registry. The registry will be a decade old in 2018 and, as of August 2017, had recruited 4758 patients encompassing 97% of immunology centres within the United Kingdom. This represents a doubling of recruitment into the registry since we reported on 2229 patients included in our first report of 2013. Minimum PID prevalence in the United Kingdom is currently 5·90/100 000 and an average incidence of PID between 1980 and 2000 of 7·6 cases per 100 000 UK live births. Data are presented on the frequency of diseases recorded, disease prevalence, diagnostic delay and treatment modality, including haematopoietic stem cell transplantation (HSCT) and gene therapy. The registry provides valuable information to clinicians, researchers, service commissioners and industry alike on PID within the United Kingdom, which may not otherwise be available without the existence of a well‐established registry.

Clinical and laboratory features of seventy-eight UK patients with Good’s syndrome (thymoma and hypogammaglobulinaemia): Good’s syndrome in the UK

Good’s syndrome (thymoma and hypogammaglobulinaemia) is a rare secondary immunodeficiency disease, previously reported in the published literature as mainly individual cases or small case series. We use the national UK‐Primary Immune Deficiency (UKPID) registry to identify a large cohort of patients in the UK with this PID to review its clinical course, natural history and prognosis. Clinical information, laboratory data, treatment and outcome were collated and analysed. Seventy‐eight patients with a median age of 64 years, 59% of whom were female, were reviewed. Median age of presentation was 54 years. Absolute B cell numbers and serum immunoglobulins were very low in all patients and all received immunoglobulin replacement therapy. All patients had undergone thymectomy and nine (12%) had thymic carcinoma (four locally invasive and five had disseminated disease) requiring adjuvant radiotherapy and/or chemotherapy. CD4 T cells were significantly lower in these patients with malignant thymoma. Seventy‐four (95%) presented with infections, 35 (45%) had bronchiectasis, seven (9%) chronic sinusitis, but only eight (10%) had serious invasive fungal or viral infections. Patients with AB‐type thymomas were more likely to have bronchiectasis. Twenty (26%) suffered from autoimmune diseases (pure red cell aplasia, hypothyroidism, arthritis, myasthenia gravis, systemic lupus erythematosus, Sjögren’s syndrome). There was no association between thymoma type and autoimmunity. Seven (9%) patients had died. Good’s syndrome is associated with significant morbidity relating to infectious and autoimmune complications. Prospective studies are required to understand why some patients with thymoma develop persistent hypogammaglobulinaemia.

The Clinical Manifestations, Management and Outcomes of Activated PI3K-Delta Syndrome (APDS) in UK and Ireland Cohort

describes the study design to facilitate the enrollment of patients treated in clinical settings. Study: All females who become pregnant during IgHy treatment (treated while pregnant or in the 30 days prior to conception) will be encouraged to participate. As soon as the patient becomes aware of the pregnancy, treatment with IgHy will be stopped. Subjects will receive an alternative gammaglobulin treatment and all other medical care will be performed as is standard. The overall duration of the study is approximately 6 years and there is no minimum sample size pre-specified. Data from medical records on the routine assessments during the pregnancy will be collected. In those subjects consenting to blood drawing, samples will be taken to assess antibodies against rHuPH20 every 3 months. Data will be assessed on the development of the fetus in utero, and on the growth and development of the infant for 2 years after delivery. Descriptive methods will be used to analyze and report data from this IgHy pregnancy registry. ESID-0098 Non-Interventional Post-Authorization Safety Study (PASS) on the Long-Term Safety of HYQVIA® (IGHY) K. Fielhauer, N. Nikolov, C. Hermann, A. Nagy, R.I. Schiff Bioscience, Baxter Healthcare, Vienna, Austria Bioscience, Baxter Healthcare SA, Zurich, Switzerland Bioscience, Baxter Healthcare, Westlake Village, USA Introduction: IgHy (recombinant human hyaluronidase [rHuPH20]-facilitated subcutaneous [SC] infusion of immunoglobulin [IG]) is a novel treatment that has been approved as a replacement therapy in adults (≥18 years) with primary immunodeficiency (PID) syndromes, myeloma, and chronic lymphocytic leukemia. This is a non-interventional, prospective, uncontrolled, multi-center, open label, post-authorization safety study to be conducted in the EEA to acquire additional data (including the assessment of anti-rHuPH20 antibodies) on the long-term safety of IgHy. This abstract describes the study design to facilitate the evaluation of patients treated in a