Antibody status in children with steroid-sensitive nephrotic syndrome

Infectious Diseases and Secondary Antibody Deficiency in Patients from a Mesoregion of São Paulo State, Brazil

Our aim was to determine the secondary antibody deficiency (SAD) profiles of patients in a mesoregion of São Paulo state, Brazil, focusing on infectious diseases. Demographic characteristics, and clinical and laboratory data were obtained from electronic files; infections were classified as organ-specific and graded as mild, moderate, life-threatening, and fatal. Non-Hodgkin's lymphoma (NHL) accounted for 30% of patients, nephrotic syndrome (NS) 25%, chronic lymphocyte leukemia 20%, and multiple myeloma 15%. Patients with NS were younger than those in other groups, and hypo-γ-globulinemia was detected in 94.1%, IgG < 400 mg/dL in 60.0%, IgA < 40 mg/dL in 55.0%, and CD19 < 20 cells/mm3 in 30.0%. One hundred and one infections were found; 82.1% were classified as mild or moderate, 7.9% as life-threatening, and 3.0% as fatal. Respiratory tract infections were more prevalent (41.5%), and pneumonia accounted for 19.8%. Lower levels of infections were found in patients with NS compared with NHL (p = 0.0001). Most patients progressed to hypo-γ-globulinemia and SAD after treatment with immunosuppressants, and mild and moderate infections were predominant. These therapies are increasing in patients with different diseases; therefore, monitoring hypo-γ-globulinemia and infections may help to identify patients at high risk for severe complications, antibiotic prophylaxis or treatment, and immunoglobulin replacement.

Practical guidance for the diagnosis and management of secondary hypogammaglobulinemia: A Work Group Report of the AAAAI Primary Immunodeficiency and Altered Immune Response Committees

Secondary hypogammaglobulinemia (SHG) is characterized by reduced immunoglobulin levels due to acquired causes of decreased antibody production or increased antibody loss. Clarification regarding whether the hypogammaglobulinemia is secondary or primary is important because this has implications for evaluation and management. Prior receipt of immunosuppressive medications and/or presence of conditions associated with SHG development, including protein loss syndromes, are histories that raise suspicion for SHG. In patients with these histories, a thorough investigation of potential etiologies of SHG reviewed in this report is needed to devise an effective treatment plan focused on removal of iatrogenic causes (eg, discontinuation of an offending drug) or treatment of the underlying condition (eg, management of nephrotic syndrome). When iatrogenic causes cannot be removed or underlying conditions cannot be reversed, therapeutic options are not clearly delineated but include heightened monitoring for clinical infections, supportive antimicrobials, and in some cases, immunoglobulin replacement therapy. This report serves to summarize the existing literature regarding immunosuppressive medications and populations (autoimmune, neurologic, hematologic/oncologic, pulmonary, posttransplant, protein-losing) associated with SHG and highlights key areas for future investigation.

Seroprotection against measles in previously vaccinated children with difficult-to-treat nephrotic syndrome

BACKGROUND

Children with nephrotic syndrome (NS) are vulnerable to infections. Measles infection is an important cause of morbidity and mortality in immunosuppressed children. A suboptimal seroprotection against measles has been shown in immunocompromised children. There is limited published literature on measles immunity in children with difficult-to-treat nephrotic syndrome (DTNS). We compared the proportions of children with DTNS and healthy controls who were seroprotected against measles.

METHODS

This was a cross-sectional study. Measles-specific IgG antibodies of 108 children with DTNS (3 to 10 years of age) and an equal number of age-matched healthy controls were measured. All children had received two doses of measles-containing vaccine at 9-12 and 16-24 months of age under routine immunisation programme. Serum measles IgG antibody titres were measured by indirect ELISA. The assay results were interpreted as (1) > 11 NTU (NovaTec Units), positive/seroprotective titres; (2) 9-11, equivocal; and (3) < 9 NTU, negative. Inter- and intra-group comparisons were made to identify the disease characteristics related to seroprotection status.

RESULTS

The proportion of children with protective anti-measles antibodies (n = 70, 65%) was significantly lower in DTNS as compared to controls (n = 88, 81.48%) (p = 0.005). Their median [IQR] antibody titres were also significantly lower than those in controls (14.1 [14] NTU vs. 18.3 [15.2] NTU (p = 0.001). The age, gender, clinical subtype, duration of disease, and type of immunosuppressive therapy were not significantly different between seroprotected and non-seroprotected children with DTNS.

CONCLUSION

A significantly lower percentage of fully vaccinated children with DTNS were seroprotected against measles compared to healthy controls. A higher resolution version of the Graphical abstract is available as Supplementary information.

Infections and risk of end-stage renal disease in patients with nephrotic syndrome: a nationwide population-based case-control study

Background

Infections are a major cause of morbidity in patients with nephrotic syndrome (NS); however, the risk of infections in NS and its subsequent effect on adverse renal outcomes are not well established.

Methods

From 2000–2013 claims data, 4,856 patients with NS were identified from the Taiwanese National Health Insurance Research Database (NHIRD). In the study group, 554 patients progressing to end-stage renal disease (ESRD), as identified during follow-up, were enrolled. In the control group, two patients with NS without progression to ESRD, during the same period, matched with one patient from the study group were included. The correlation between rates of infections and risk of ESRD in patients with NS was estimated using conditional logistic regression analysis.

Results

The proportion of outpatient visits for infections in patients with NS with and without progression to ESRD was 61.2% and 32.8%, respectively, and the proportion of hospitalization due to infections was 28.9% and 1.7%, respectively. The risk of ESRD was higher in patients with frequent outpatient visits for infections (>10 outpatient visits), with a relative risk of 3.20 [95% confidence interval (CI), 1.84–5.57]. Additionally, a significant association was found between severe infections requiring hospitalization and ESRD, with a relative risk of 7.01 (95% CI, 3.65–13.44). Subgroup analysis stratified by sex or age indicated that the risk associated with ESRD was significantly higher in female and elderly patients with NS.

Conclusions

The risk of ESRD in patients with NS was linked to the incidence of infection, especially those requiring hospitalization due to more severe bacterial infections. Implications of study results are important for clinicians who should be aware of the possibility of ESRD development in patients with NS with infectious complications.

A unified pathogenesis for kidney diseases, including genetic diseases and cancers, by the protein-homeostasis-system hypothesis

Every cell of an organism is separated and protected by a cell membrane. It is proposed that harmony between intercellular communication and the health of an organism is controlled by a system, designated the protein-homeostasis-system (PHS). Kidneys consist of a variety of types of renal cells, each with its own characteristic cell-receptor interactions and producing characteristic proteins. A functional union of these renal cells can be determined by various renal function tests, and harmonious intercellular communication is essential for the healthy state of the host. Injury to a kind of renal cells can impair renal function and induce an imbalance in total body health. Every acute or chronic renal disease has unknown etiologic substances that are responsible for renal cell injury at the molecular level. The immune/repair system of the host should control the etiologic substances acting against renal cells; if this system fails, the disease progresses to end stage renal disease. Each renal disease has its characteristic pathologic lesions where immune cells and immune proteins, such as immunoglobulins and complements, are infiltrated. These immune cells and immune proteins may control the etiologic substances involved in renal pathologic lesions. Also, genetic renal diseases and cancers may originate from a protein deficiency or malfunctioning protein under the PHS. A unified pathogenesis for renal diseases, including acute glomerulonephritis, idiopathic nephrotic syndrome, immunoglobulin A nephropathy, genetic renal diseases such as Alport syndrome, and malignancies such as Wilms tumor and renal cell carcinoma, is proposed using the PHS hypothesis.

Immunoglobulin G and M levels in childhood nephrotic syndrome: two centers Egyptian study

INTRODUCTION

Idiopathic nephrotic syndrome (INS) is the most common glomerular disease in children. Immune cell subsets may play a role in pathogenesis of INS. We aimed to assess immunoglobulin G (IgG) and immunoglobulin M (IgM) levels in children with nephrotic syndrome (NS) to predict prognosis of the disease and response to treatment.

METHODS

This prospective case control study was done in Pediatric Nephrology Units at Minoufia and Benha University Hospitals, during the period from 1st March 2014 to 30th June 2015. Seventy-five children in the active stage of INS and 75 apparently healthy children of matched age and sex were included in this study. Statistical evaluation was performed by SPSS version 18.0 using independent-samples t-test, Chi-square, and Pearson's correlation coefficient (r).

RESULTS

Compared with healthy children, IgM level was high, IgG level and IgG/IgM ratio were low (p≤0.05). The IgG level and IgG/IgM ratio decreased more in FRNS than in IFRNS group, and was the lowest in SRNS group. The IgM level increased more in FRNS than in IFRNS group, and was the highest in SRNS group (p<0.05, respectively).

CONCLUSIONS

Our findings support the idea that IgG level has a prognostic value in NS in children.

Vaccinations in children on immunosuppressive medications for renal disease

Renal diseases are often treated with immunosuppressive medications, placing patients at risk of infections, some of which are vaccine-preventable. However, in such patients vaccinations may be delayed or disregarded due to complications of the underlying disease process and challenges in its management. The decision to administer vaccines to immunosuppressed children is a risk-benefit balance as such children may have a qualitatively diminished immunological response or develop diseases caused by the vaccine pathogen. Vaccination may cause a flare-up of disease activity or provocation of graft rejection in renal transplant recipients. Moreover, it cannot be assumed that a given antibody level provides the same protection in immunosupressed children as in healthy ones. We have evaluated the safety and efficacy of licensed vaccines in children on immunosuppressive therapy and in renal transplant recipients. The limited evidence available suggests that vaccines are most effective if given early, ideally before the requirement for immunosuppressive therapy, which may require administration of accelerated vaccine courses. Once treatment with immunosuppressive drugs is started, inactivated vaccines are usually considered to be safe when the disease is quiescent, but supplemental doses may be required. In the majority of cases, live vaccines are to be avoided. All vaccines are generally contraindicated within 3-6 months of a renal transplant.

A common immunopathogenesis mechanism for infectious diseases: the protein-homeostasis-system hypothesis

It was once believed that host cell injury in various infectious diseases is caused solely by pathogens themselves; however, it is now known that host immune reactions to the substances from the infectious agents and/or from the injured host cells by infectious insults are also involved. All biological phenomena in living organisms, including biochemical, physiological and pathological processes, are performed by the proteins that have various sizes and shapes, which in turn are controlled by an interacting network within the living organisms. The author proposes that this network is controlled by the protein homeostasis system (PHS), and that the immune system is one part of the PHS of the host. Each immune cell in the host may recognize and respond to substances, including pathogenic proteins (PPs) that are toxic to target cells of the host, in ways that depend on the size and property of the PPs. Every infectious disease has its own set of toxic substances, including PPs, associated with disease onset, and the PPs and the corresponding immune cells may be responsible for the inflammatory processes that develop in those infectious diseases.

Seroprotection for hepatitis B in children with nephrotic syndrome

BACKGROUND

Children with nephrotic syndrome have been shown to have lower seroconversion to various vaccines due to immune dysregulation, prolonged immunosuppressive treatment and recurrent prolonged proteinuria.The primary aim of this study was to determine hepatitis B surface antibody (anti-HBs) titers in children with nephrotic syndrome who had been previously vaccinated against hepatitis B. The secondary aim was to study the association of anti-HBs titers with type of disease, schedule and dose of vaccination, and type of immunosuppressive therapy.

METHODS

This cross-sectional study was conducted in the Department of Pediatrics in a tertiary care hospital between January 2011 and January 2012). All children (aged 1-18 years) with nephrotic syndrome who tested negative for hepatitis B surface antigen and who had previously been vaccinated against hepatitis B, with the last dose being at least 1 month prior to being included in the study. A form consisting of history and clinical details was filled in, and the schedule and dose of vaccination(s) received was noted. A blood sample was taken from all patients for biochemical assessment and determination of anti-HBs titer.

RESULTS

The patient cohort comprised 75 children (51 males; 24 females) of whom 42 (56%) had steroid-resistant nephrotic syndrome (SRNS) and 33 (44%) had steroid-sensitive nephrotic syndrome (SSNS). Most patients enrolled in the study (96%) were in remission at the time of the biochemical and serological assessment. Twenty-one (28%) patients had received only steroids, while 72 % also received other immunosuppressants. Forty-six (61.3%) patients had received a double dose of vaccine. Of the 75 children enrolled, 36 (48%) and 39 (52%) had an anti-HBs titer of ≥10 mIU/mL (seroprotected) and <10 mIU/mL (unprotected), respectively. The mean titer among all patients was 143.58 mIU/mL. The seroprotection rates were 63.6% in SSNS patients and 35.7% in SRNS subjects (P = 0.016).

CONCLUSIONS

Based on our results, we conclude that children with SRNS are less likely to seroconvert with vaccination. A higher dose (double) of hepatitis B vaccine should be used for vaccinating such patients. Anti-HBs titers should be monitored in SRNS patients post-vaccination, and a booster should be given if titers fall to <10 mIU/mL.