The Use of Immunoglobulin Therapy for Patients With Primary Immune Deficiency: An Evidence-Based Practice Guideline

Relationships between bronchiectasis and time to achieving target trough immunoglobulin G levels in patients with common variable immunodeficiency

Background: The main treatment of common variable immunodeficiency (CVID) is to maintain immunoglobulin G (IgG) levels within the target range. However, trough IgG levels differ among patients with similar body mass index (BMI) and those receiving the same dose of immunoglobulin replacement therapy (IGRT). A crucial factor that underlies these differences is the presence of extensive bronchiectasis, which is associated with the immunoglobulin salvage pathway. Objective: We compared trough IgG levels in patients with CVID and with and in those without bronchiectasis who had received the same dose of IGRT for 2 years to determine the association of IgG level with infection frequency. Method: This retrospective cohort study included 61 patients with CVID, of whom 21 had bronchiectasis. We reviewed the electronic records for demographic variables, baseline immunoglobulin levels, mean trough IgG levels over 2 years, efficacy levels (trough IgG level - baseline IgG level), the time interval from treatment initiation to achieving the target trough IgG level (700 mg/dL), and the number of infections. Results: The median age of the patients was 39 years (IQR, 27-51), and 29 were women (47.5%). There were no significant differences between the groups in terms of age, age at diagnosis, delay in diagnosis, sex, BMI, IGRT type (subcutaneous or intravenous), and baseline immunoglobulin levels. Trough IgG and efficacy levels were lower (P < 0.001 and P = 0.016, respectively), the time required to achieve the target IgG level was longer in patients with bronchiectasis than in those without bronchiectasis, and this time interval was significantly associated with the infection frequency. Trough IgG and albumin levels were correlated (p = 0.007), with minor differences between the groups (p = 0.04). Conclusion: Bronchiectasis was significantly associated with a longer time to achieve the target IgG levels. These long-term differences between the patients with and those without bronchiectasis have significant clinical implications.

Immunoglobulin replacement products protect against SARS-CoV-2 infection in vivo despite poor neutralizing activity

Immunoglobulin (IG) replacement products are used routinely in patients with immune deficiency and other immune dysregulation disorders who have poor responses to vaccination and require passive immunity conferred by commercial antibody products. The binding, neutralizing, and protective activity of intravenously administered IG against SARS-CoV-2 emerging variants remains unknown. Here, we tested 198 different IG products manufactured from December 2019 to August 2022. We show that prepandemic IG had no appreciable cross-reactivity or neutralizing activity against SARS-CoV-2. Anti-spike antibody titers and neutralizing activity against SARS-CoV-2 WA1/2020 D614G increased gradually after the pandemic started and reached levels comparable to vaccinated healthy donors 18 months after the diagnosis of the first COVID-19 case in the United States in January 2020. The average time between production to infusion of IG products was 8 months, which resulted in poor neutralization of the variant strain circulating at the time of infusion. Despite limited neutralizing activity, IG prophylaxis with clinically relevant dosing protected susceptible K18-hACE2-transgenic mice against clinical disease, lung infection, and lung inflammation caused by the XBB.1.5 Omicron variant. Moreover, following IG prophylaxis, levels of XBB.1.5 infection in the lung were higher in FcγR-KO mice than in WT mice. Thus, IG replacement products with poor neutralizing activity against evolving SARS-CoV-2 variants likely confer protection to patients with immune deficiency disorders through Fc effector function mechanisms.

Trends in intravenous immunoglobulin use in New South Wales, Australia

BACKGROUND

Intravenous immunoglobulin (IVIg) is a critical replacement therapy for immunodeficiencies and immunomodulatory treatment for autoimmune and inflammatory diseases. Adequate supply of IVIg is a global issue, necessitating supply restrictions. In Australia, despite strict criteria for use, demand for IVIg has increased over time and exceeds domestic supply.

OBJECTIVE

Factors associated with the upward trend in overall IVIg use were examined, including in the number of unique patients, IVIg dosing and treatment frequency and variations by prescribing discipline and disease group.

METHODS

De-identified data of IVIg dispensed in the largest Australian state (New South Wales) from 2007 to 2013 were provided by Australian Red Cross Lifeblood. Trends and projections were calculated using log-linear regression of unique patients, treatment episodes and grams of IVIg for overall use and use stratified by discipline and disease group.

RESULTS

During the study period, 169 453 treatment episodes were recorded for 12 547 unique patients accounting for 5 827 787 g of IVIg use. Overall, IVIg use increased by 12.0% (11.5-12.6%) per year representing a 97.7% increase (91.6-104%) over the study period. The highest growth was among neurological conditions (16.0% (14.9-17.1%) per year). An increase in the number of unique patients was the primary driver of this growth, augmented by increases in the frequency and average dose per treatment.

CONCLUSIONS

Clinically acceptable measures to improve management of IVIg supply are needed including optimising dose, frequency and duration of treatment. Formal evaluation of IVIg versus alternatives, including cost-effectiveness and comparative efficacy, is warranted.

Screening for Antibody Deficiencies in Adults by Serum Electrophoresis and Calculated Globin

PURPOSE

This study aimed to investigate the correlation between calculated globulin (CG, total protein level minus albumin level) and the gamma globulin fraction (Gamma), obtained from serum protein electrophoresis with serum IgG levels in adults (≥ 18 years).

METHODS

Using linear regression models, analyses of CG and Gamma levels correlation with IgG levels in adults were performed. Receiver-operator curves were created to determine cutoff values and the respective sensitivity and specificity measures.

RESULTS

A total of 886 samples were analyzed. CG and Gamma were positively and statistically correlated with IgG levels (r2 = 0.4628 for CG, and = 0.7941 for Gamma, p < 0.0001 for both analyses). For the detection of hypogammaglobulinemia, i.e., IgG level below the reference value (6 g/L), a CG cutoff value of 24 g/L showed a sensitivity of 86.2% (95% CI 69.4-94.5) and a specificity of 92% (90.0-93.6). A Gamma cutoff value of 7.15 g/L yielded a sensitivity of 100% (88.3-100) and a specificity of 96.8 (95.3-97.8).

CONCLUSION

Both CG and Gamma levels determined by protein electrophoresis analysis may be used to screen for antibody deficiencies in adults, enabling earlier diagnosis of antibody deficiencies in a routine clinical setting.

Patient-reported outcomes in patients with primary immunodeficiency diseases in Japan: baseline results from a prospective observational study

Introduction

Primary immunodeficiency diseases (PIDs) are rare inherited diseases resulting in impaired immunity. People with PID experience lower health-related quality of life (HR-QOL) and disease-related burdens in daily activities. This ongoing, prospective observational study aims to evaluate disease activity, treatment status, treatment-related burden, daily activities, and HR-QOL in patients with PID in Japan over a 1-year period. In this interim report (database lock: July 29, 2022), we present baseline results.

Methods

Participants were enrolled between November 2021 and May 2022; data were collected four times/year per participant until May 2023 using an online electronic patient-reported outcomes system. Patients with PID and healthy volunteers aged ≥12 years, residing in Japan, and with access to a smartphone were eligible. HR-QOL (primary endpoint) was assessed by the EuroQol-5 Dimensions-5 Levels (EQ-5D-5L) and the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36). Work productivity was assessed by the Work Productivity and Activity Impairment (WPAI) Questionnaire. Other aspects of PID and burden were assessed with a new questionnaire developed in-house. The study is registered at the University hospital Medical Information Network clinical trials registry (UMIN000045622).

Results

The full interim analysis set comprised 71 patients with PID and 47 healthy volunteers. The most common International Union of Immunological Societies PID category was primary antibody deficiency (56.3% of patients). Complications were common, especially recurrent respiratory tract infections (63.4%). Most patients with PID were treated with immunoglobulin replacement therapy (73.2%); 22.4% of these patients had serum immunoglobulin levels <700 mg/dL. Among patients who did not undergo hematopoietic cell transplantation, EQ-5D-5L (n=67) and SF-36 (n=59) Physical and Mental Component Summary scores were significantly lower than in healthy volunteers (p < 0.001). WPAI absenteeism, work productivity loss, and activity impairment scores were significantly lower in 42 working patients with PID than in 37 working healthy volunteers (p < 0.05). Other results indicated that patients with PID experience substantial burdens related to medical visits, expenses, work, and daily activities.

Discussion

This interim analysis confirms that patients with PID in Japan have lower HR-QOL and work productivity compared with healthy individuals and experience substantial limitations and burdens in their daily lives.

Guardians of Immunity: Advances in Primary Immunodeficiency Disorders and Management

Primary immunodeficiency disorders (PIDs) are a heterogeneous group of genetic conditions profoundly impacting immune function. The investigation spans various PID categories, offering insights into their distinct pathogenic mechanisms and clinical manifestations. Within the adaptive immune system, B-cell, T-cell, and combined immunodeficiencies are dissected, emphasizing their critical roles in orchestrating effective immune responses. In the realm of the innate immune system, focus is directed toward phagocytes and complement deficiencies, underscoring the pivotal roles of these components in initial defense against infections. Furthermore, the review delves into disorders of immune dysregulation, encompassing hemophagocytic lymphohistiocytosis (HLH), autoimmune lymphoproliferative syndrome (ALPS), immune dysregulation, polyendocrinopathy, enteropathy, and X-linked(IPEX), and autoimmunity polyendocrinopathy candidiasis-ectodermal dystrophy(APECED), elucidating the intricate interplay between immune tolerance and autoimmunity prevention. Diagnostic strategies for PIDs are explored, highlighting advancements in genetic and molecular techniques that enable precise identification of underlying genetic mutations and alterations in immune function. We have also outlined treatment modalities for PIDs, which often entail a multidisciplinary approach involving immunoglobulin replacement, antimicrobial prophylaxis, and, in select cases, hematopoietic stem cell transplantation. Emerging therapies, including gene therapy, hold promise for targeted interventions. In essence, this review encapsulates the complexity of PIDs, emphasizing the critical importance of early diagnosis and tailored therapeutic interventions. As research advances, a clearer understanding of these disorders emerges, fostering optimism for enhanced patient care and management in the future.

Immunodeficiency due to a novel variant in PIK3CD: a case report

BACKGROUND

Primary immunodeficiencies are immunological disorders caused by gene mutations involved in immune system development and activation. Recently, activated phosphoinositide 3-kinase delta syndrome (APDS) due to mutations in the phosphoinositide 3-kinase (PI3K), phosphatidylinositol-4, 5-bisphosphate 3-kinase, catalytic subunit delta gene (PIK3CD), and phosphoinositide 3-kinase regulatory subunit 1 (PIK3R1) genes have been reported to induce a combined immunodeficiency syndrome leading to senescent T cells, lymphadenopathy, and immunodeficiency. The exact diagnosis of these deficiencies is essential for treatment and prognosis. In recent years, targeted treatment with selective PI3Kd inhibitors has had a significant effect on controlling the symptoms of these patients.

CASE PRESENTATION

In this case report, we represent a 27-month-old girl with recurrent fever, an increased level of inflammatory markers, and erythema nodosum, who was referred to the rheumatology clinic. In the course of evaluations, because of the lack of clinical improvement with usual treatments, and a history of frequent respiratory infections, combined immunodeficiency was diagnosed in the immunological investigations. Moreover, whole-exome sequencing was performed for her.

CONCLUSION

The genetic analysis found a novel variant of PIK3CD (c.1429 G > A) in the patient. Following daily antibiotic prophylaxis and monthly IV therapy, the patient's frequent infections and fevers were controlled.

The Evolutionary Scenario of Pediatric Unclassified Primary Antibody Deficiency to Adulthood

BACKGROUND

Unclassified primary antibody deficiency (unPAD) is a relatively novel inborn error of immunity (IEI) condition that can vary with time to more defined entities. Since long-term follow-up (FU) studies are scarce, we aimed to provide insight into the evolutionary clinical and immunological scenario of unPAD children to adulthood and identification of biomarkers of primary immune deficiency (PID) persistence.

METHODS

A total of 23 pediatric unPAD patients underwent clinical and immunological FU for a mean time of 14 years (range 3-32 years, median 16 years).

RESULTS

UnPAD diagnosis may change over time. At the last FU, 10/23 (44%) children matched the diagnosis of transient hypogammaglobulinemia of infancy and 13/23 (56%) suffered from a persistent PID. In detail, an unPAD condition was confirmed in 7/23 (30%) patients, whereas 3/23 (13%), 2/23 (9%), and 1/23 (4%) were reclassified as common variable immunodeficiency, selective IgA deficiency, and isolated IgM deficiency, respectively. Low IgA, low specific antibody response to pneumococcus, and lower respiratory tract infections at diagnosis were independently associated with IEI persistence.

CONCLUSIONS

Long-term monitoring of unPAD patients is required to define their outcome and possible evolution towards a definitive IEI diagnosis.

Evaluation of immunoglobulin replacement therapy in secondary immunodeficiency at three British Columbia hospitals

BACKGROUND AND OBJECTIVES

Immunoglobulin (Ig) usage has ongoing shortage concerns. Secondary immunodeficiencies (SIDs) account for a major proportion of usage of Igs in Canada. We audited Ig usage in patients with SID at three British Columbia hospitals to determine whether more stringent local guidelines are necessary.

MATERIALS AND METHODS

A retrospective chart review was performed for patients who had Ig ordered between 1 January 2018 and 31 December 2019 for any SID indication. Cohorts were stratified into chronic and new users, and the Australian BloodSTAR guidelines were used as the benchmark at the time of conception. Having an eligible primary diagnosis, meeting SID criteria, an appropriate dosage and follow-up immunoglobulin G (IgG) levels encompassed appropriate usage.

RESULTS

There were no demographic differences between chronic (N = 81) and new (N = 33) cohorts. The new cohort had a higher rate of appropriate usage (45.7% vs. 66.7%, p = 0.06). The most common reason for inappropriate usage in both groups was the lack of follow-up IgG level at 6 or 12 months. Factors, displayed by relative risk (RR), associated with appropriateness included the dispensing hospital (RR: 6.60), use of subcutaneous Ig (RR: 3.84), having an IgG level before starting therapy (RR: 3.51) and documentation of clinical benefit (RR: 4.70).

CONCLUSION

There are high rates of inappropriate Ig usage in SID patients in both new and chronically treated groups. More stringent local guidelines and processes for assessing initial and ongoing Ig replacement are warranted.

Mechanisms of Obesity-Induced Changes in Pharmacokinetics of IgG in Rats

PURPOSE

To evaluate how obesity affects the pharmacokinetics of human IgG following subcutaneous (SC) and intravenous (IV) administration to rats and the homeostasis of endogenous rat IgG.

METHODS

Differences in body weight and size, body composition, and serum concentration of endogenous rat IgG in male Zucker obese (ZUC-FA/FA) and control (ZUC-LEAN) rats were measured from the age of 5 weeks up to 30 weeks. At the age of 23-24 weeks animals received a single IV or SC dose of human IgG (1 g/kg of total body weight), and serum pharmacokinetics was followed for 7 weeks. A mechanistic model linking obesity-related changes in pharmacokinetics with animal growth and changes in body composition was developed.

RESULTS

Significant differences were observed in both endogenous and exogenous IgG pharmacokinetics between obese and control groups. The AUC for human IgG was lower in obese groups (57.6% of control after IV and 48.1% after SC dosing), and clearance was 1.75-fold higher in obese animals. The mechanistic population model successfully captured the data and included several major components: endogenous rat IgG homeostasis with age-dependent synthesis rate; competition of human IgG and endogenous rat IgG for FcRn binding and its effect on endogenous rat IgG concentrations following injection of a high dose of human IgG; and the effect of body size and composition (changing over time and dependent on the obesity status) on pharmacokinetic parameters.

CONCLUSIONS

We identified important obesity-induced changes in the pharmacokinetics of IgG. Results can potentially facilitate optimization of the dosing of IgG-based therapeutics in the obese population.

Physician awareness and understanding of primary immunodeficiency disorders: a web-based study in Japan

Primary immunodeficiencies (PIDs)/Inborn errors of immunity (IEI) consist of a complex genetic group of disorders that cause susceptibility to infections, inflammation, immune dysregulation, autoimmunity, and malignancy. One of the key steps to reach an early diagnosis is improving knowledge of PID among the medical community. In this study, a web-based survey was conducted among 355 Japanese physicians, consisting of 121 pediatricians, 116 hematologists, and 118 general internal medicine physicians, to assess their awareness and knowledge about the diagnostic flow of PID. One of the major problems this study identified was the unawareness of optimal IgG trough levels among the physicians, while around half the physicians knew about the symptoms of PID. Results from the hypothetical case study revealed that over 70% of physicians considered PID after obtaining the past medical history of patients and 75.2% of physicians showed interest in gaining more knowledge about PID. The survey findings revealed that proper questioning to understand the exact medical history of patients may lead to basic immunological examination. There is a need to improve knowledge about PID, e.g., the '10 warning signs of PID' and '4 stages of testing for PID', and to motivate physicians to ensure earlier diagnosis of PID.

Gene Editing in Human Haematopoietic Stem Cells for the Treatment of Primary Immunodeficiencies

In recent years, gene-editing technologies have revolutionised precision medicine, and human trials of this technology have been reported in cell-based cancer therapies and other genetic disorders. The same techniques have the potential to reverse mutations in monogenic primary immunodeficiencies (PIDs), and transplantation of edited haematopoietic stem cells may provide a functional cure for these diseases. In this review, we discuss the methods of gene editing being explored and describe progress made so far with several PIDs. We also detail the remaining challenges, how to confidently detect off-target effects and chromosomal abnormalities in a timely manner, how to obtain long-term benefits, and how to achieve physiological levels of expression of the therapeutic gene. With advances in gene editing, we envisage a robust clinical translation of this technology in the coming decade.

Placebo and nocebo effects in transfusion medicine

BACKGROUND

Our own observations suggested that placebo and nocebo effects may occur with transfusions. However these effects seem to have been poorly studied.

OBJECTIVES

To examine published information on, and draw attention to the possibility of, placebo and nocebo effects with transfusion.

METHODS

Focused literature review.

RESULTS

There is some information on placebo effects with clotting factors and this effect appears modest at best. There is very little published information on this regarding other fresh blood components. Although unknown biologic effects cannot be ruled out, there are hints that placebo effects might operate - especially with red blood cell transfusions. There is practically no information on nocebo effects with transfusions.

CONCLUSIONS

There are ways of surmounting the practical and ethical difficulties involved, and obtaining better information on both types of effects. Individualised, contextualised, informed consenting of transfusion recipients may help to enhance placebo, and reduce nocebo, effects. This may be supportable ethically, and desirable clinically, and financially.

Facilitated subcutaneous immunoglobulin use in pediatric patients with primary or secondary immunodeficiency diseases

Aim: While facilitated subcutaneous immunoglobulin (fSCIG) has been evaluated in pediatric patients with primary immunodeficiency diseases in clinical trials, real-world data are lacking. Materials & methods: This multicenter, retrospective, chart review study assessed fSCIG utilization in 30 patients less than 18 years old, with primary or secondary immunodeficiency diseases. Medical records were reviewed at fSCIG initiation and at 6 months. Results: Most (90%) patients received their first fSCIG infusion at a medical facility; by 6 months, all fSCIG infusions were administered at home by the patient/caregiver, the majority infusing every 3-4 weeks into a single site. No serious adverse drug reactions occurred. Conclusion: This study supports the feasibility and tolerability of administering fSCIG at home to pediatric patients with immunodeficiencies. Clinical Trial Registration: DRKS00015436 (German Clinical Trials Register).

Serum Protein Electrophoresis May Be Used as a Screening Tool for Antibody Deficiency in Children and Adolescents

Background

Patients with antibody deficiency may experience exceptionally long diagnostic delays, increasing the risk of life-threatening infections, end-organ damage, mortality, and health costs.

Objective

This study aimed to analyze serum protein electrophoresis and verify the correlation between calculated globulin (CG, total protein minus albumin levels) or electrophoretically determined serum gamma globulin fraction (Gamma) with IgG levels in children and adolescents under 18 years old (yo).

Methods

We analyzed serum protein electrophoresis (GC or Gamma) and IgG levels from 1215 children and adolescents under 18 yo, classified into 5 age groups. We verified the correlation between CG or Gamma with serum IgG levels.

Results

Serum IgG levels varied according to age groups (from 4.3 ± 2.3 g/l in children under 6 months old to 11.4 ± 3.2 g/l in adolescents in the 10-<18 yo group). CG sensitivity and specificity to detect IgG below the reference range for all patients were 93.1% and 81.8%, respectively, and varied according to age group. Gamma sensitivity and specificity for all patients were 100% and 87.8%, respectively, and varied according to age group as well. We found serum IgG levels below the age reference level in 29 patients (2.4% of the cases) using CG or Gamma levels.

Conclusion

Both CG and Gamma levels may be of utility as a screening tool for earlier diagnosis of antibody deficiency in children and adolescents under 18 yo.

Effectiveness of low-dose intravenous immunoglobulin therapy in minor primary antibody deficiencies: A 2-year real-life experience

Primary antibody deficiencies (PAD) are the most prevalent group of primary immunodeficiencies (PID) in adults and immunoglobulin replacement therapy (IRT) is the mainstay therapy to improve clinical outcomes. IRT is, however, expensive and, in minor PAD, clear recommendations concerning IRT are lacking. We conducted a retrospective real-life study to assess the effectiveness of low-dose IRT in minor PAD on 143 patients fulfilling European Society for Immunodeficiencies (ESID) diagnostic criteria for immunoglobulin (Ig)G subclass deficiency (IgGSD) or unclassified antibody deficiency (UAD). All patients were treated with intravenous low-dose IRT (0.14 ± 0.06 g/kg/month). Immunoglobulin (Ig) classes and IgG subclasses were measured at baseline and after 1 year of IRT. The annual rate of total infections, upper respiratory tract infections (URTI), lower respiratory tract infections (LRTI) and hospitalizations was measured at baseline and after 1 and 2 years of IRT. After 1 year of IRT significant improvement was demonstrated in: (a) serum IgG (787.9 ± 229.3 versus 929.1 ± 206.7 mg/dl; p < 0.0001); (b) serum IgG subclasses (IgG1 = 351.4 ± 109.9 versus 464.3 ± 124.1, p < 0.0001; IgG2 = 259.1 ± 140 versus 330.6 ± 124.9, p < 0.0001; IgG3 = 50.2 ± 26.7 versus 55.6 ± 28.9 mg/dl, p < 0.002); (c) annual rate of total infections (5.75 ± 3.87 versus 2.13 ± 1.74, p < 0.0001), URTI (1.48 ± 3.15 versus 0.69 ± 1.27; p < 0.005), LRTI (3.89 ± 3.52 versus 1.29 ± 1.37; p < 0.0001) and hospitalizations (0.37 ± 0.77 versus 0.15 ± 0.5; p < 0.0002). The improvement persisted after 2 years of IRT. No significant improvement in URTI annual rate was noted in UAD and in patients with bronchiectasis. In conclusion, low-dose IRT can improve clinical outcomes in UAD and IgGSD patients, providing a potential economical advantage over the standard IRT dose.

Steady-State Serum IgG Trough Levels Are Adequate for Pharmacokinetic Assessment in Patients with Immunodeficiencies Receiving Subcutaneous Immune Globulin

Patients with primary immunodeficiency diseases often require lifelong immunoglobulin (IG) therapy. Most clinical trials investigating IG therapies characterize serum immunoglobulin G (IgG) pharmacokinetic (PK) profiles by serially assessing serum IgG levels. This retrospective analysis evaluated whether steady-state serum IgG trough level measurement alone is adequate for PK assessment. Based on individual patient serum IgG trough levels from two pivotal trials (phase 2/3 European [NCT01412385] and North American [NCT01218438]) of weekly 20% subcutaneous IG (SCIG; Cuvitru, Ig20Gly), trough level-predicted IgG AUC (AUC_τ,tp) were calculated and compared with the reported AUC calculated from serum IgG concentration-time profiles (AUC_τ). In both studies, mean AUC_τ,tp values for Ig20Gly were essentially equivalent to AUC_τ with point estimates of geometric mean ratio (GMR) of AUC_τ,tp/AUC_τ near 1.0 and 90% CIs within 0.80-1.25. In contrast, for IVIG, 10%, mean AUC_τ,tp values were lower than AUC_τ by >20%, (GMR [90% CI]: 0.74 [0.70-0.78] and 0.77 [0.73-0.81] for the two studies, respectively). Mean AUC_τ,tp values calculated for 4 other SCIG products (based on mean IgG trough levels reported in the literature/labels) were also essentially equivalent to the reported AUC_τ (differences <10% for all except HyQvia, a facilitated SCIG product), while differences for IVIG products were >20%. In conclusion, steady-state serum IgG levels following weekly SCIG remain stable, allowing for reliable prediction of AUC over the dosing interval using trough IgG levels. These findings indicate that measuring steady-state serum IgG trough levels alone may be adequate for PK assessment of weekly SCIG.

Immunologic Phenotype of a Child With the MEHMO Syndrome

MEHMO syndrome is a rare X-linked syndrome characterized by Mental retardation, Epilepsy, Hypogenitalism, Microcephaly, and Obesity associated with the defect of protein synthesis caused by the EIF2S3 gene mutations. We hypothesized that the defect in protein synthesis could have an impact on the immune system. We describe immunologic phenotype and possible treatment outcomes in patient with MEHMO syndrome carrying a frame-shift mutation (I465fs) in the EIF2S3 gene. The proband (currently 9-year-old boy) had normal IgG and IgM levels, but had frequent respiratory and urinary tract infections. On subcutaneous immunoglobulin therapy achieving supra-physiological IgG levels the frequency of infections significantly decreased in Poisson regression by 54.5 % (CI 33.2-89.7, p=0.017). The MEHMO patient had had frequent acute infections despite normal IgG and IgM serum levels and responded well to the immunoglobulin treatment.

A Systematic Review and Meta-regression Analysis on the Impact of Increasing IgG Trough Level on Infection Rates in Primary Immunodeficiency Patients on Intravenous IgG Therapy

PURPOSE

We conducted a systematic review and meta-regression analysis to evaluate the impact of increasing immunoglobulin G (IgG) trough levels on the clinical outcomes in patients with PID receiving intravenous immunoglobulin G (IVIG) treatment.

METHODS

Systematic search was conducted in PubMed and Cochrane. Other relevant articles were searched by reviewing the references of the reviewed article. All clinical trials with documented IgG trough levels and clinical outcome of interest in patients receiving IVIG treatment were eligible to be included in this review. Meta-regression analysis was conducted using Comprehensive Meta-analysis Software. Additional sensitivity analyses were undertaken to evaluate the robustness of the overall results.

RESULTS

Twenty-eight clinical studies with 1218 patients reported from year 2001 to 2018 were included. The mean IVIG dose used ranges from 387 to 560 mg/kg every 3 to 4 weekly, and mean IgG trough obtained ranges from 660 to 1280 mg/dL. Random-effects meta-regression slope shows that IgG trough level increases significantly by 73 mg/dL with every increase of 100 mg/kg dose of IVIG (p < 0.05). Overall infection rates reduced significantly by 13% with every increment of 100 mg/dL of IgG trough up to 960 mg/dL (p < 0.05).

CONCLUSION

This meta-analysis concludes that titrating the IgG trough levels up to 960 mg/dL progressively reduces the rate of infections, and there is less additional benefit beyond that. Further studies to validate this result are required before it can be used in clinical practice.

Oral management of a patient with down syndrome and agammaglobulinemia: a case report

BACKGROUND

Down syndrome is characterized by a variety of dysmorphic features and congenital malformations, such as congenital heart disease, gastrointestinal disease, and other conditions like leukemia and autoimmune disorders. Patients with Down syndrome are highly prone to respiratory tract infections, which might be fatal to them. However, there are only few available data on patients diagnosed with Down syndrome and agammaglobulinemia. In this report, we describe a case of successful prevention of post-dental treatment complications (e.g., pneumonia and other bacterial infections) in a patient with Down syndrome and agammaglobulinemia.

CASE PRESENTATION

A 43-year-old man with Down syndrome, untreated agammaglobulinemia, and a history of recurrent pneumonia, was referred to our clinic for tooth mobility. To reduce the risk of post-operative infections, gammaglobulin treatment and prophylactic administration of antibiotics was scheduled before the dental procedure. Furthermore, the dental treatment, which included a filling and extractions, was conducted under general anesthesia and with the supervision of a hematologist. The dental procedures were successfully performed without any post-operative infection, and the patient is undergoing follow-up care.

CONCLUSIONS

The purpose of this case report was to recommend a close liaison between physicians and dentists who may encounter a similar case, and to emphasize the importance of improving oral health of immunodeficient patients to prevent infections caused by oral microbial flora.

The influence of hospital-based intravenous immunoglobulin and home-based self-administrated subcutaneous immunoglobulin therapy in young children with primary immunodeficiency diseases on their parents' / caregivers' satisfaction

BACKGROUND

Immunoglobulin replacement has been standard therapy for patients with primary immunodeficiency diseases (PIDD). Intravenous immunoglobin (IVIg) is delivered at the hospital, whereas subcutaneous immunoglobin (SCIg) is used for home-based treatment. The aim of the study was to determine the advantages and disadvantages of IVIg and SCIg in Polish children aged 1-5 years, with PIDD, and the satisfaction of their parents / caregivers regarding immunoglobulin replacement.

METHODS

The research involved parents of 23 children with PIDD, aged 1-5 years. All children were given IVIg therapy and after at least 6 months they were switched towards home SCIg therapy for at least 6 months. A questionnaire assessing advantages and disadvantages of preferred types of treatment and the quality of life of PIDD patients' families' lives was used.

RESULTS

The research showed that IVIg therapy was better accepted by parents than SCIg therapy (P = 0.034) for the following reasons: It made it possible for the children to receive treatment once per month (60%); it reduced the fear of injecting the children (60%), and it provided better control of the disease through regular visits to the hospital (53.33%). Parents noticed, however, that IVIg had a significant impact on absence at school or work (70%). Parents who preferred SCIg for their children were guided mainly by the smaller number of side effects (40%), and the fact that the treatment did not interfere with parents' work or the children's school (40%).

CONCLUSION

The results showed that IVIg therapy was better accepted by parents than SCIg therapy Parents of children with SCIg are less satisfied with their life, and feel anxiety about their children disease, which is related to administering the medicine by themselves.

Primary Immunodeficiencies: Diseases of Children and Adults - A Review

Primary immunodeficiencies (PIDs) belong to a group of rare congenital diseases occurring all over the world that may be seen in both children and adults. In most cases, genetic predispositions are already known. As shown in this review, genetic abnormalities may be related to dysfunction of the immune system, which manifests itself as recurrent infections, increased risk of cancer, and autoimmune diseases. This article reviews the various forms of PIDs, including their characterization, management strategies, and complications. Novel aspects of the diagnostics and monitoring of PIDs are presented.

Prevalence of Hypogammaglobulinemia in Adult Invasive Pneumococcal Disease

Background

Patients with humoral immune deficiency are susceptible to invasive pneumococcal disease (IPD). This study estimates the prevalence of underlying hypogammaglobulinemia in admitted IPD cases and examines whether IPD cases had received preventative treatment.

Methods

All adult IPD cases (Streptococcus pneumoniae in blood or cerebrospinal fluid) admitted to The Ottawa Hospital (TOH) from January 2013 to December 2015 were identified through the Eastern Ontario Regional Laboratory. Documented clinical demographics, S. pneumoniae serotype, serum immunoglobulins measured previously or in convalescence, and vaccination status of the cases were collected retrospectively for descriptive analyses.

Results

There were 134 IPD in 133 patients (47.4% male; mean age 63, standard deviation [SD] = 15.6 years) during a 3-year observation period. All-cause mortality rate was 22.6% over a mean follow-up time of 362, SD = 345 days. Fifty-seven patients (42.9%) had serum immunoglobulin levels measured. Eighteen were either found to have hypogammaglobulinemia in convalescence (8/18) or previously known to have hypogammaglobulinemia (10/18). None of the known hypogammaglobulinemic patients had received antibiotic prophylaxis and/or immunoglobulin replacement therapy within 4 months prior to IPD. The high and low estimates of prevalence of hypogammaglobulinemia were 31.6% (of all measured) and 13.5% (of all cases). Among 18 patients with hematological malignancies in our cohort, 13 had hypogammaglobulinemia. Many isolates were vaccine serotypes; however, only 8 had documented previous pneumococcal vaccination.

Conclusions

IPD has high mortality, and hypogammaglobulinemia was present in at least 13.5% of IPD cases. Secondary hypogammaglobulinemia is especially common in cases with hematological malignancy and IPD.

Focus on Chronic Variable Immunodeficiency for Primary Care Practitioners, the Gatekeepers to Optimal Health Outcomes for Primary Immunodeficiency Syndromes

Purpose of Review

This review sought to assess the extent and causes of suboptimal healthcare outcomes for chronic variable immunodeficiency (CVID).

Recent Findings

Significant improvements in diagnostic technology and treatment protocols over time were found, leading to reduced morbidity and mortality for those accessing therapies. Treatments continue to be largely non-curative with financing (mainly insurance coverage) an obstacle. Symptom recognition by primary care practitioners (PCP) remains a gating factor to treatment and a widespread and persistent barrier to optimal health outcomes.

Summary

CVID is a subtype of primary immunodeficiency (PIDD) associated with under-diagnosis. It has emerged as a health issue more prevalent than historically known. No symptom-recognition framework for early detection of CVID has been generally accepted; those proposed for primary immunodeficiencies have shown low sensitivity, low specificity or both. Positive trends in cases diagnosed have been aided by awareness campaigns and international collaborations. However, treatments for CVID will not realize full potential without effective, accepted frameworks for timely identification in the clinic.

Trends in IVIG use at a tertiary care Canadian center and impact of provincial use mitigation strategies: 10-year retrospective study with interrupted time series analysis

BACKGROUND

Intravenous immunoglobulin (IVIG) is a fractionated plasma product used to treat a range of autoimmune or inflammatory conditions, as well as immunodeficiency. Demand for this high-cost product is increasing worldwide. Understanding historical changes in IVIG use is important for inventory management and demand forecasting as well as for the development of initiatives aimed at optimizing blood product use.

STUDY DESIGN AND METHODS

This was a 10-year retrospective cohort study of all patient encounters involving an IVIG transfusion from 2007 to 2016 at a four-site tertiary care hospital in Ontario, Canada. IVIG use was reported, including number of hospital encounters and amounts of IVIG prescribed. An interrupted time series analysis was performed to evaluate temporal changes in product use coinciding with the release of 2009-2010 provincial initiatives to optimize IVIG.

RESULTS

A total of 1,658,159.50 g of IVIG was administered from 2007 to 2016. Total annual volume administered initially decreased after implementation of new policies (-2032 g/quarter). The number of IVIG patient encounters also decreased (-49.8 encounters/quarter) but was mirrored by an increase in the total volume administered per patient encounter (+0.88 g/quarter). Use increased 820 g/quarter from 2013 to 2016 but was 21% lower than projected before implementation of provincial policies.

CONCLUSION

Trends in IVIG use show ongoing increases in the number of patients treated with the product. Development and implementation of provincial initiatives to optimize IVIG use coincided with significant short-term changes at a large tertiary care hospital. Novel initiatives aimed at dose minimization and prescription rationalization for this therapy are needed on local as well as larger scales.

CD40 ligand deficiency: treatment strategies and novel therapeutic perspectives

INTRODUCTION

CD40 ligand (CD40L) deficiency or X-linked Hyper-IgM syndrome is a severe primary immunodeficiency caused by mutations in the CD40L gene. Despite currently available treatments, CD40L-deficient patients remain susceptible to life-threatening infections and have poor long term survival. Areas covered: Here, we discuss clinical and immunological characteristics of CD40L deficiency as well as current therapeutic strategies used for patient management. This review highlights that beyond B cell defects, patients' susceptibility to opportunistic pathogens might be due to impaired T cell and innate immune responses. In this context, we discuss how better knowledge of CD40L function and regulation may result in the development of new treatments. Expert opinion: Despite the introduction of hematopoietic stem-cell transplantation, immunoglobulin replacement, granulocyte colony-stimulating factor (G-CSF) administration, and prophylactic antibiotic therapies, life-threatening infections still cause high morbidity and mortality among CD40L-deficient patients. The reasons for this inadequate response to current therapies remains poorly understood, but recent reports suggest the involvement of CD40L-CD40 interaction in early stages of the innate immune system ontogeny. The development of novel gene therapeutic approaches and the use of redirected immunotherapies represent alternative treatment methods that could offer reduced morbidity and mortality rates for patients with CD40L deficiency.

Direct and Indirect Costs of Immunoglobulin Replacement Therapy in Patients with Common Variable Immunodeficiency (CVID) and X-Linked Agammaglobulinemia (XLA) in Italy

BACKGROUND

In Italy, there is scarce evidence on the epidemiological and economic burden induced by primary antibody deficiencies.

OBJECTIVE

The aim of this study was to elaborate the available epidemiological and cost data in order to estimate the annual expenditure induced by the management of patients affected by the common variable immunodeficiency (CVID) and X-linked agammaglobulinemia (XLA) requiring immunoglobulin (Ig) replacement therapy.

METHODS

A probabilistic cost-of-illness model was developed to estimate the number of patients with CVID and XLA, and the economic burden associated with their therapy in terms of direct or indirect costs. A systematic literature review was carried out to reveal both epidemiological and economic data. Furthermore, a probabilistic sensitivity analysis with 5000 Monte Carlo simulations was performed.

RESULTS

The epidemiological model allowed us to estimate the number of prevalent patients affected by XLA and CVID in Italy in 2017, corresponding to 1885 (95% confidence interval [CI] 944-3145) and 133 (95% CI 115-152) patients, respectively. The estimated total expenditure for the treatment and management of patients with CVID and XLA requiring Ig replacement therapy amounts to €42.68 million (95% CI €14.38-€86.1 million).

CONCLUSIONS

This information provides a comprehensive perspective of the economic issues, and facilitates better-informed public health decision making, in the management of CVID and XLA in Italy.

Passive transfer of anti-HBc after intravenous immunoglobulin administration in patients with cancer: a retrospective chart review

BACKGROUND

Patients previously infected with hepatitis B virus (HBV; indicated by positivity for anti-HBc) can experience HBV reactivation during cancer chemotherapy. Intravenous immunoglobulin infusion, which is frequently used in supportive care, might facilitate passive transfer of anti-HBc. We aimed to estimate the probability of passive transfer of anti-HBc after intravenous immunoglobulin infusion in patients with cancer.

METHODS

We reviewed institutional databases to identify adult patients who received outpatient chemotherapy between Jan 1, 2004, and Dec 31, 2011, at the University of Texas MD Anderson Cancer Center, Houston, TX, USA. Eligible patients had received intravenous immunoglobulin therapy, had tested negative for both anti-HBc and HBsAg before infusion, and had been tested for anti-HBc after infusion. The primary endpoint was the proportion of patients who became positive for anti-HBc after intravenous immunoglobulin infusion.

FINDINGS

950 of 18 874 patients who underwent chemotherapy within the study time frame received intravenous immunoglobulin, of whom 870 had been tested for anti-HBc before infusion. 199 patients who were negative for anti-HBc before receiving intravenous immunoglobulin were retested after infusion, of whom 29 (15% [95% CI 10-20]) became positive for anti-HBc. The probability of anti-HBc conversion at 1 week after intravenous immunoglobulin infusion was 34% (95% CI 22-48) and at 12 weeks was 4% (2-7).

INTERPRETATION

Conversion of patients from anti-HBc negativity to anti-HBc positivity was common after intravenous immunoglobulin administration. However, the probability of a positive test decreased with time since infusion. Positive anti-HBc tests done shortly after intravenous immunoglobulin infusion should be interpreted with caution because they might indicate passive transfer instead of true infection.

FUNDING

None.

Combined Treatment with Zinc Aspartate and Intravenous Immunoglobulins (IVIGs) Ameliorates Experimental Autoimmune Encephalomyelitis (EAE)

Intravenous immunoglobulins (IVIGs) are widely used in replacement therapy of primary and secondary immunodeficiency disorders and in approved autoimmune indications. In addition, IVIG application is used off-label for treatment of other autoimmune diseases, e.g., multiple sclerosis (MS), an inflammatory autoimmune disorder with a clear T cell-mediated immune pathogenesis. The trace element zinc is shown to play a regulatory role in the maintenance of immune functions. Changes of zinc homeostasis affect both the innate and the adaptive immune system. On one hand, therapeutic zinc supplementation can normalize impaired immune functions due to zinc deficiency. On the other hand, therapeutic zinc supplementation is under consideration as a possible option to treat T cell-mediated autoimmune diseases. The aim of the present study was to investigate the influence of IVIG (Octagam®), zinc aspartate (Unizink®), and the combined application of both preparations in the experimental autoimmune encephalomyelitis (EAE), the animal model of MS. Therapeutic intraperitoneal application of zinc aspartate significantly diminished clinical signs during the relapsing-remitting phase of EAE in SJL/J mice. In contrast, IVIG given in a therapeutic manner did not influence the course of EAE. Interestingly, the combined application of both, IVIG and zinc aspartate, significantly reduced the severity of the disease during the acute and the relapsing-remitting phase of the EAE. Our data suggest that the combination of IVIG and zinc aspartate may have beneficial effects in autoimmune diseases, like MS. Further studies should verify the benefit of a controlled immunosuppressive therapy with IVIG and zinc for such diseases.

Primary immunodeficiency

Primary immunodeficiency disorder (PID) refers to a large heterogeneous group of disorders that result from defects in immune system development and/or function. PIDs are broadly classified as disorders of adaptive immunity (i.e., T cell, B-cell or combined immunodeficiencies) or of innate immunity (e.g., phagocyte and complement disorders). Although the clinical manifestations of PIDs are highly variable, many disorders involve an increased susceptibility to infection. Early consultation with a clinical immunologist is essential, as timely diagnosis and treatment are imperative for preventing significant disease-associated morbidity. PIDs should be suspected in patients with: recurrent sinus or ear infections or pneumonias within a 1 year period; failure to thrive; poor response to prolonged use of antibiotics; persistent thrush or skin abscesses; or a family history of PID. Patients with multiple autoimmune diseases should also be evaluated. Diagnostic testing often involves lymphocyte proliferation assays, flow cytometry, measurement of serum immunoglobulin (Ig) levels, assessment of serum specific antibody titers in response to vaccine antigens, neutrophil function assays, stimulation assays for cytokine responses, and complement studies. The treatment of PIDs is complex and generally requires both supportive and definitive strategies. Ig replacement therapy is the mainstay of therapy for B-cell disorders, and is also an important supportive treatment for many patients with combined immunodeficiency disorders. The disorders affecting the activity of the T-cell arm of the adaptive system, such as severe combined immunodeficiency, require immune reconstitution as soon as possible. The treatment of innate immunodeficiency disorders varies depending on the type of defect, but may involve antifungal and antibiotic prophylaxis, cytokine replacement, vaccinations and bone marrow transplantation. This article provides an overview of the major categories of PIDs and strategies for the appropriate diagnosis and management of these rare disorders.

II Brazilian Consensus on the use of human immunoglobulin in patients with primary immunodeficiencies

In the last few years, new primary immunodeficiencies and genetic defects have been described. Recently, immunoglobulin products with improved compositions and for subcutaneous use have become available in Brazil. In order to guide physicians on the use of human immunoglobulin to treat primary immunodeficiencies, based on a narrative literature review and their professional experience, the members of the Primary Immunodeficiency Group of the Brazilian Society of Allergy and Immunology prepared an updated document of the 1^st Brazilian Consensus, published in 2010. The document presents new knowledge about the indications and efficacy of immunoglobulin therapy in primary immunodeficiencies, relevant production-related aspects, mode of use (routes of administration, pharmacokinetics, doses and intervals), adverse events (major, prevention, treatment and reporting), patient monitoring, presentations available and how to have access to this therapeutic resource in Brazil.

Occurrence of acute renal failure on the same day as immune globulin product administrations during 2008 to 2014

BACKGROUND

Acute renal failure (ARF) is a rare serious adverse event after immune globulin (IG) use. Our large claims-based study evaluated occurrence of same-day ARF after administration of different IGs and ascertained potential risk factors, during the 2008 to 2014 study period.

STUDY DESIGN AND METHODS

A retrospective cohort study was conducted using a large commercial administrative database. The cohort included individuals exposed to IG products as identified by procedure codes. ARF was ascertained using ICD-9-CM diagnoses. Unadjusted same-day ARF rates (per 1000 persons exposed) were estimated overall and by age, sex, and IG products. Regression analyses were conducted to control for confounding and assess potential risk factors.

RESULTS

Of 20,440 persons exposed, 163 (7.97 per 1000) had a recorded same-day ARF. The unadjusted nonzero same-day ARF rates (per 1000) ranged from 1.92 (95% confidence interval [CI], 0.05-10.69) for Hizentra to 16.97 (95% CI, 11.36-24.37) for Privigen and differed by sex. In multivariate analyses, compared to Gammagard Liquid, no significantly elevated ARF risks were identified with any IGs. A significantly lower odds ratio was identified with Gamunex, 0.53 (95% CI, 0.30-0.93). Age 45 and over, prior renal impairment, hypertension, and other factors were associated with increased risk of same-day ARF.

CONCLUSION

The study showed variation in the risk of IG-related ARF by age, sex, and IG products. The study results suggest the importance of recipient factors, such as older age and underlying health conditions. Variations in ARF occurrence may also be explained by product dosage, administration route and rate, and manufacturing processes, which warrant further evaluation.

Periodontal and other oral manifestations of immunodeficiency diseases

The list of immunodeficiency diseases grows each year as novel disorders are discovered, classified, and sometimes reclassified due to our ever-increasing knowledge of immune system function. Although the number of patients with secondary immunodeficiencies (SIDs) greatly exceeds those with primary immunodeficiencies (PIDs), the prevalence of both appears to be on the rise probably because of scientific breakthroughs that facilitate earlier and more accurate diagnosis. Primary immunodeficiencies in adults are not as rare as once thought. Globally, the main causes of secondary immunodeficiency are HIV infection and nutritional insufficiencies. Persons with acquired immune disorders such as AIDS caused by the human immunodeficiency virus (HIV) are now living long and fulfilling lives as a result of highly active antiretroviral therapy (HAART). Irrespective of whether the patient's immune-deficient state is a consequence of a genetic defect or is secondary in nature, dental and medical practitioners must be aware of the constant potential for infections and/or expressions of autoimmunity in these individuals. The purpose of this review was to study the most common conditions resulting from primary and secondary immunodeficiency states, how they are classified, and the detrimental manifestations of these disorders on the periodontal and oral tissues.

Audit of provincial IVIG Request Forms and efficacy documentation in four Ontario tertiary care centres

OBJECTIVE

Retrospective audit of IVIG Request Forms in four Ontario tertiary care centres: to determine the case mix of new IVIG requests, to authenticate information provided, and to determine documentation of clinical efficacy.

AIMS

To understand contributors to increases in IVIG utilisation and to determine whether IVIG is being used and monitored appropriately.

INTRODUCTION

Intravenous immunoglobulin (IVIG) use in Canada is high compared with other developed countries. We performed a retrospective audit of new IVIG Request Forms across four tertiary care centres in Ontario, one with an active surveillance programme, to determine the case mix, authenticate information provided and assess documentation of efficacy.

METHODS

Consecutive adult patients with a first-time IVIG request in 2014 were included. The ordering physician specialty, form completeness, documentation of diagnostic criteria for the medical condition and indication for IVIG use and documentation of efficacy were assessed by form and chart review.

RESULTS

Of 178 patients, the most common indications for IVIG were immune thrombocytopenia (24.2%) and secondary immune deficiency (20.2%). The most frequent prescribers were haematologists (37.6%) and neurologists (10.7%). Other conditions not listed on the form represented 24.2% of cases, with most not indicated in current guidelines. A total of 32.6% of cases overall lacked verification of diagnostic criteria and 51.7% lacked verification for IVIG utilisation criteria, with the number of cases meeting criteria based on documentation being higher at the active surveillance site (P = 0.005). A total of 19.1% of cases had a discrepancy between the indication written on the form and the documented clinical diagnosis. A total of 18.7% of clinic notes following IVIG had no mention of efficacy.

CONCLUSION

Our audit demonstrates a lack of compliance with IVIG Request Form requirements, a lack of documentation of diagnostic criteria and efficacy, and suggests inappropriate use of IVIG. Current implementation of the form may not be sufficient as a strategy for improving appropriate IVIG use.

Primary immunodeficiencies in Chile evaluated through ICD-10 coded hospital admissions

BACKGROUND

The epidemiology and hospitalisation trends of primary immunodeficiency (PID) in Chile are unknown. We aimed to evaluate hospitalisation trends and demographic characteristics of PID admissions in Chile.

METHODS

PID admissions between 2001 and 2010 (ICD-10 codes D70.0, D70.4, D71, 72.0, D76.1, D80-D84, E70.3, G11.3) were reviewed using national hospital discharge databases.

RESULTS

During the study period, 5486 admissions due to PID were registered (0.03% of total). 58.5% of patients were male and 66.3% were under 18 years. Median length of stay was one day (range 1-403 days). The most frequent diagnoses were hypogammaglobulinaemia (27.6%), unspecified immunodeficiency (21.9%), haemophagocytic lymphohystiocytosis (18.3%) and common variable immunodeficiency (11.2%). There was a significant increase in PID admission rate and in one-day hospitalisations during this period (β=0.2; P=0.001 and β=33; P≤0.001, respectively), however no significant variation was found for longer admissions (β=4.8; P=0.175). The increasing trend in PID admission rate was significant in patients with private, but not public insurance (β=0.53; P≤0.001 vs. β=0.08; P=0.079, respectively).

CONCLUSIONS

We report an increasing trend in admissions due to PID in Chile over a 10-year period. Increase is mainly due to short hospitalisations, possibly accounting for improvements in IVIG access. Higher admission rates in patients with private vs. public insurance suggest socioeconomic disparities in access to PID treatment. ICD-10 coded hospitalisation databases may be useful to determine hospitalisation trends and demographic characteristics of PID admissions worldwide.

Update on the use of immunoglobulin in human disease: A review of evidence

Human immunoglobulin preparations for intravenous or subcutaneous administration are the cornerstone of treatment in patients with primary immunodeficiency diseases affecting the humoral immune system. Intravenous preparations have a number of important uses in the treatment of other diseases in humans as well, some for which acceptable treatment alternatives do not exist. We provide an update of the evidence-based guideline on immunoglobulin therapy, last published in 2006. Given the potential risks and inherent scarcity of human immunoglobulin, careful consideration of its indications and administration is warranted.

Efficacy, Safety, and Pharmacokinetics of a Novel Human Immune Globulin Subcutaneous, 20 % in Patients with Primary Immunodeficiency Diseases in North America

Patients with primary immunodeficiency disease (PIDD) typically require life-long intravenous (IV) or subcutaneous (SC) immunoglobulin (Ig) replacement therapy to prevent recurrent infections. The efficacy, safety, and pharmacokinetics of a highly concentrated (20 %) Ig preparation for SC administration (IGSC 20 %) were evaluated in a prospective trial in patients with PIDD. A total of 74 patients (aged 3-83 years) received 4327 IGSC 20 % infusions over a median of 380.5 days. The rate of validated serious bacterial infections was 0.012 event/patient-year (p < 0.0001 compared with the historical control), and the annualized rate of infection was 2.41 events/patient. Median IgG trough levels were >14.5 g/l. The median maximum infusion rate was 60 ml/h/site (range 4.4-180), resulting in a median infusion duration of 0.95 h. A volume ≥30 ml was infused per site in 74.8 % of IGSC 20 % infusions. Most (84.9 %) infusions were administered using ≤2 infusion sites; for 99.8 % of infusions, there was no need to interrupt/stop administration or reduce the infusion rate. No related serious adverse event (AE) occurred during IGSC 20 % treatment; related non-serious AEs occurred at a rate of 0.036 event/infusion. The incidence of related local AEs was 0.015 event/infusion and of related systemic AEs was 0.021 event/infusion; most were mild in severity, none severe. Increased infusion rates or volumes were not associated with higher AE rates. The investigated IGSC 20 % treatment was shown to be effective and safe, enabling higher infusion rates and volumes per site compared to conventional SC treatments, resulting in fewer infusion sites and shorter infusion durations.

Clinical Experience with Octagam® 10 %, a solvent detergent virus inactivated intravenous immunoglobulin: a Canadian retrospective review of utilization

In Canada, intravenous immune globulin (IVIg) products are licensed for six disease indications, however it has been demonstrated that patients with a number of other conditions also benefit from IVIg. Here we report the routine clinical use of Octagam^® 10 % across three Canadian institutions. A total of 135 patients were treated with Octagam^®, for conditions represented by five distinct indication groups. The results of this review indicate that Octagam^® has been well adopted and is prescribed to Canadian patients similar to other IVIg products. In alignment with current practices, 85 % of Octagam’s utilization was classified as appropriate based on Canadian IVIg guidelines.

Common variable immunodeficiency in adults requires reserved protocols for long-term follow-up

BACKGROUND/AIM

The aim of this study is to establish follow-up protocols for adult patients with common variable immunodeficiency (CVID) in a recently founded adult immunology clinic in the Central Anatolia Region of Turkey, where a clinical immunology center for adults was not available previously.

MATERIALS AND METHODS

A total of 25 patients with CVID aged 18 years and older were included in this study. The file format consisted of 13 pages and was developed for the purpose of the study. Separate sections were designated for identity information, medical history, disease course, previous and current laboratory and imaging studies, follow-up plans, detection and management of complications/comorbidities, and treatment results.

RESULTS

The mean age of the patients was 36.6 ± 13.4 years. The delay in diagnosis was 107 ± 95.6 months. In 92% of patients, initial symptoms resulting in admission to healthcare facilities were infections. Seventeen of 25 patients (68%) had bronchiectasis at the beginning of follow-up.

CONCLUSION

Early identification of complications and comorbidities in patients with CVID will significantly improve quality of life and survival. Close observation and standardized protocols for follow-up are essential components of management.

A Canadian perspective on the use of immunoglobulin therapy to reduce infectious complications in chronic lymphocytic leukemia

Infections are a major cause of morbidity and mortality in patients with chronic lymphocytic leukemia (cll), who typically have increased susceptibility because of hypogammaglobulinemia (hgg) related to their disease and its treatment. Immunoglobulin replacement therapy (igrt) has been shown to reduce the frequency of bacterial infections and associated hospitalizations in patients with hgg or a history of infection, or both. However, use of igrt in cll is contentious. Studies examining such treatment were conducted largely before the use of newer chemoimmunotherapies, which can extend lifespan, but do not correct the hgg inherent to the disease. Thus, the utility of igrt has to be re-evaluated in the current setting. Here, we discuss the evidence for the use of igrt in cll and provide a practical approach to its use in the prevention and management of infections.

Diagnostics of primary immunodeficiency diseases: a sequencing capture approach

Primary Immunodeficiencies (PID) are genetically inherited disorders characterized by defects of the immune system, leading to increased susceptibility to infection. Due to the variety of clinical symptoms and the complexity of current diagnostic procedures, accurate diagnosis of PID is often difficult in daily clinical practice. Thanks to the advent of “next generation” sequencing technologies and target enrichment methods, the development of multiplex diagnostic assays is now possible. In this study, we applied a selector-based target enrichment assay to detect disease-causing mutations in 179 known PID genes. The usefulness of this assay for molecular diagnosis of PID was investigated by sequencing DNA from 33 patients, 18 of which had at least one known causal mutation at the onset of the experiment. We were able to identify the disease causing mutations in 60% of the investigated patients, indicating that the majority of PID cases could be resolved using a targeted sequencing approach. Causal mutations identified in the unknown patient samples were located in STAT3, IGLL1, RNF168 and PGM3. Based on our results, we propose a stepwise approach for PID diagnostics, involving targeted resequencing, followed by whole transcriptome and/or whole genome sequencing if causative variants are not found in the targeted exons.

Should development of Alzheimer's disease-specific intravenous immunoglobulin be considered?

Recent phase II and III studies with intravenous immunoglobulin (IVIG) in patients with Alzheimer's disease (AD) did not find evidence for the slowing of AD progression compared to placebo-treated patients, in contrast to encouraging results in pilot studies. An additional phase III trial is ongoing. If negative results are found, then further AD studies with IVIG are unlikely unless a manufacturer opts for a trial with high-dose IVIG, which would increase its anti-inflammatory effects but also the risk for adverse events. An alternative approach could be an AD-specific IVIG, supplementing IVIG with higher concentrations of selected antibodies purified from it or produced via recombinant polyclonal antibody technology. These antibodies could include those to amyloid-beta (Aβ, tau protein, inflammatory cytokines, complement activation proteins, and the receptor for advanced glycation end products. IgG fragment crystallizable (Fc) fragments containing terminal sialic acid could be added to increase anti-inflammatory effects. While this product might be more effective in slowing AD clinical progression than current IVIG, there are difficulties with this approach. Preclinical studies would be required to determine which of the antibodies of interest for supplementing current IVIG (for example, antibodies to phosphorylated or oligomeric tau) are actually present (and, therefore, available for purification) in IVIG, and the effects of the product in mouse models of AD. An Investigational New Drug application for an AD-specific IVIG would require United States Food and Drug Administration approval. If the drug would be found to benefit AD patients, meeting the increased demand for IVIG would be challenging.