Immunoglobulins in chronic renal failure of childhood: effects of dialysis modalities

Lower serum AMH concentration is correlated with serum IgG1 decreased in the infertile woman: A real-world retrospective study

OBJECTIVES

In this real-world approach, we examined the serum Anti-Mullerian Hormone (AMH) level and the relationship with serum IgG subclass in the infertile women.

METHODS

A total of 574 female participants were recruited for this study. The serum AMH, IgG subclass(IgG1, IgG2, IgG3, IgG4) and immunoglobulin (Ig) G、IgM、IgA、IgE as well as complement C3, C4 were analyzed. The difference in serum AMH level was assessed according categorized as above or below the median of the ratio of serum IgG subclass(IgG1, IgG2, IgG3, IgG4) to total IgG (RIgG subclass/IgG).

RESULTS

The serum AMH level of the low RIgG1/IgG group is significantly decreased than that high RIgG1/IgG group (p < 0.05). The Spearman correlation analysis showed that the serum AMH level was significantly negatively correlated with age and significantly positively correlated with serum IgG1 levels respectively (p < 0.05). GLMMs multivariate model showed that after adjusting the covariate and possible mixed factors including age, serum immunoglobulin, complement C3 and C4, the serum AMH level was significantly positively correlated with IgG1 level (p < 0.01).

CONCLUSIONS

Decreased serum IgG1 may significantly affect the ovarian reserve function of women. Confirmation of this association and elucidation of its underlying mechanisms are needed to place these results in a clinical perspective.

Distribution characteristics of circulating B cell subpopulations in patients with chronic kidney disease

This study compared the levels of circulating B cell subpopulations in patients with different stages of chronic kidney disease (CKD), investigated the effects of haemodialysis (HD) on the B cell-related immune spectrum in patients with end-stage renal disease, and evaluated the link between renal function and immune homeostasis. Overall, 197 patients with CKD (158 non-dialysis patients with CKD stages I-V and 39 end-stage patients undergoing maintenance HD) and 77 healthy controls were included. Compared to healthy controls, patients with CKD stages I-II showed no significant differences except for the proportion of transitional B cells; patients with CKD stage V showed a significant decrease in the proportions of transitional B cells and CD5+ B cells and a significant increase in double-negative (DN) B cells. Compared with early-stage patients with CKD, the absolute count of various B cell subpopulations in advanced-stage patients with CKD showed a significant decrease. The distribution of circulating B cell subpopulations in patients with CKD was significantly altered and was associated with CKD progression. Furthermore, the proportion of DN B cells and CD5+ B cells was inconsistent pre- and post-HD. This in-depth study of the immune status of patients with CKD may have important clinical value.

Hypogammaglobulinemia in neonates: illustrative cases and review of the literature

This article presents a review of causes of hypogammaglobulinemia in neonates utilizing illustrative cases to demonstrate commonly seen conditions. Overall, the causes of low immunoglobulin level can be divided into three main categories: decreased maternal transfer or production (due to physiological nadir, transient hypogammaglobulinemia of infancy, medication effects, or immunodeficiency), increased loss of immunoglobulins (from the gastrointestinal (GI) system, lymphatics, kidneys, skin disease, or blood loss) or destruction/suppression (from medication effects). Treatment of hypogammaglobulinemia is generally tailored to the underlying cause and condition of the patient. This can be through supportive care, prophylactic measures, or with immunoglobulin G (IgG) replacement at the recommendation of an immunologist.

Urinary tract infections in patients with renal insufficiency and dialysis - epidemiology, pathogenesis, clinical symptoms, diagnosis and treatment

Epidemiological studies show an increasing number of patients worldwide suffering from chronic kidney diseases (CKD), which are associated with a risk for progression to end-stage kidney disease (ESKD). CKD patients stage 2-5, patients with regular chronic dialysis treatment (hemo- or peritoneal dialysis), and patients suffering from kidney allograft dysfunction are at high risk to develop infections, e.g. urinary tract infections (UTI) and/or sepsis (urosepsis). These groups show metabolic disturbance, chronic inflammation, and impaired immunocompetence. Escherichia coli is still the most common pathogen in UTI. A wide variety of other pathogens may be involved in UTI. Urological interventions, catheterization, as well as repeated courses of antibiotics contribute to an increased challenge of antimicrobial resistance. The diagnosis of UTI in CKD is based on standard clinical and laboratory criteria. Pyuria (≥10 leucocytes/µl) is more often observed in patients with oligoanuria and low bacterial colony counts. The treatment strategies for this population are based on the same principles as in patients with normal renal function. However, drugs cleared by the kidney or by dialysis membranes need dose adjustment. Antimicrobials with potential systemic toxicity and nephrotoxicity should be administered with caution.

Clinical Pharmacology and Interplay of Immune Checkpoint Agents: A Yin-Yang Balance

T cells have a central role in immune system balance. When activated, they may lead to autoimmune diseases. When too anergic, they contribute to infection spread and cancer proliferation. Immune checkpoint proteins regulate T cell function, including cytotoxic T lymphocyte antigen-4 (CTLA-4) and programmed cell death-1 (PD-1) and its ligand (PD-L1). These nodes of self-tolerance may be exploited pharmacologically to downregulate (CTLA-4 agonists) and activate [CTLA-4 and PD-1/PD-L1 antagonists, also called immune checkpoint inhibitors (ICIs)] the immune system.CTLA-4 agonists are used to treat rheumatologic immune disorders and graft rejection. CTLA-4, PD-1, and PD-L1 antagonists are approved for multiple cancer types and are being investigated for chronic viral infections. Notably, ICIs may be associated with immune-related adverse events (irAEs), which can be highly morbid or fatal. CTLA-4 agonism has been a promising method to reverse such life-threatening irAEs. Herein, we review the clinical pharmacology of these immune checkpoint agents with a focus on their interplay in human diseases.

Peritoneal Transport Kinetics of Proteins in Children on Chronic Peritoneal Dialysis

Objective

This study describes a modified 4-hour peritoneal equilibration test (PET) for analyzing peritoneal transport characteristics of proteins with different molecular weights and predicting daily peritoneal protein losses in children on chronic peritoneal dialysis (PD).

Design

Cross-sectional study.

Setting

A single regional pediatric dialysis unit in a teaching hospital.

Patients

9 stable pediatric dialysis patients; 4 were on continuous ambulatory PD, 5 were on continuous cycling PD.

Main Outcome Measures

Serum and dialysate concentrations of IgG, albumin, β2-microglobulin, and transferrin were determined during a PET. Changes in dialysate-to-plasma (D/P) ratios were determined hourly. Agreement between PET-derived and measured daily peritoneal protein losses was examined.

Results

The D/P ratio decreased with increased molecular radius ( p < 0.0001). Many children had low plasma levels of IgG, albumin, and transferrin, but elevated levels of β2-microglobulin. The D/P ratio increased linearly during the PET for all measured proteins, regardless of molecular weight. There was close correlation between 4-hour PET protein losses and 24-hour losses during routine PD.

Conclusions

Proteins are lost through the peritoneum according to their size, demonstrating linear transport kinetics during a 4-hour PET. The PET-derived data predicted daily protein losses in children on chronic PD. This approach might help to eliminate inaccuracies due to incomplete dialysate collection.

Characteristics of Peripheral and Peritoneal White Blood Cells in Children with Chronic Renal Failure, Dialyzed or Not

Objective

To explore further the mechanisms leading to immune deficiency in chronic renal failure and the role of dialysis treatment in these mechanisms.

Design

Cross-sectional and longitudinal analysis.

Patients

We studied 39 children treated with peritoneal dialysis (PD), 23 children treated with hemodialysis (HD), 33 children not yet dialyzed [chronic renal failure (CRF)], and 27 healthy children. Peritoneal cells were also obtained from PD children for analysis.

Methods

White blood cells (WBCs) were isolated from blood and peritoneal dialysis effluent by centrifugation. The number of CD2+, CD4+, and CD8+T cells, B cells, and natural killer cells were measured by flow cytometry.

Results

The total peripheral blood lymphocyte count was lower in PD children (2.6 x 109/L), HD children (2.1 x 109/L), and CRF children (2.0 x 109/L) compared with healthy children (3.1 x 109/L, p < 0.05). The B lymphocyte count was also lower in PD children (0.34x109/L), HD children (0.22 x 109/L), and CRF children (0.33 x 109/L) compared with healthy children (0.52 x 109/L, p < 0.01). Numbers of CD4+T cells were not different, but numbers of CD8+T cells were lower in PD children (0.56 x 109/L), HD children (0.63 x 109/L), and CRF children (0.53 x 109/L) compared with healthy children (0.77 x 109/L, p < 0.05). The count of natural killer cells was lower in PD children (0.21 x 109/L), HD children (0.17 x 109/L), and CRF children (0.18 x 109/L) compared with healthy children (0.50 x 109/L, p < 0.0001). The CD4/CD8 ratio of lymphocytes in peritoneal effluent was 0.8 versus 1.9 in peripheral blood ( p < 0.001). The CD2/CD19 ratio was not different. The cell subsets remained stable during the first year of PD treatment. The CD2/CD19 ratio in peritoneal effluent was higher in children with a peritonitis incidence ≥ 1 per year.

Conclusions

The reduced numbers of B lymphocytes, CD8+T cells, and natural killer cells found in CRF children, dialyzed or not, may favor the frequent occurrence of infections.

Nephrologists need to play a key role in improving annual influenza vaccination rates in children with kidney disease

AIM

This study investigated the under-researched area of annual influenza vaccination rates in children with chronic kidney disease and identified reasons for nonimmunisation.

METHODS

A prospective cross-sectional study was conducted in the nephrology clinic and dialysis unit of a tertiary paediatric medical centre from August to October 2011 and September to October 2012. Parents were asked to complete a questionnaire on their child's immunisation against influenza.

RESULTS

Of the 217 children studied, 45.6% were vaccinated against influenza. The major reason for nonimmunisation was because the parents had not received the necessary information from the primary physician or treating nephrologist. The nonvaccinated children were significantly more likely to be less than two years old and female and to have parents who did not believe in the benefits of vaccination (p < 0.05). Of the parents who did not vaccinate their child, 38% claimed they would have done so if the vaccine had been offered in the nephrology clinic.

CONCLUSION

Children with kidney disease had a higher annual influenza vaccination rate than the general population, but it was still suboptimal. Nephrologists should be alerted to the need to provide parents with information on influenza vaccinations and they should be available in nephrology clinics.

Hypogammaglobulinemia in infants receiving chronic peritoneal dialysis

BACKGROUND

Peritonitis is a severe complication of chronic peritoneal dialysis (CPD) in infants. Few studies have been conducted to evaluate the relationship between hypogammaglobulinemia and peritonitis risk, and the potential benefit of intravenous immunoglobulins (IVIG) therapy in infants receiving CPD.

METHODS

Patients aged 0-12 months at initiation of CPD between 1985 and 2012 were eligible for inclusion in this retrospective study. Data collected from the start of CPD up to 2 years post-dialysis initiation included patient demographics, dialysis characteristics, serum immunoglobulin (IgG) levels, IVIG administration history, infectious complications and outcomes. Cox regression analysis and linear mixed model analysis were used for statistical analysis.

RESULTS

Twenty-six consecutive patients were included in the study. Annualized peritonitis rates for infants aged 0-30 days (≤1-month age group; n = 16; 320.3 patient-months) and 31-365 days (>1-12-month age group; n = 10; 163.3 patient-months) at dialysis initiation were 0.27 (1 episode per 45.8 patient-months) and 0.15 (one episode per 81.7 patient-months), respectively. Seventy-six percent of the serum IgG levels were >1 standard deviation below the age-appropriate mean levels, and these did not differ in those who developed peritonitis versus those who did not (p = 0.39). Serum IgG levels were significantly lower in patients on CPD with oligoanuria than in non-oliguric patients (p = 0.04) and in patients on CPD for >90 days as compared to those who had received CPD for <90 days (p = 0.018). IVIG therapy was provided to 20 patients with hypogammaglobulinemia; this high prevalence of IVIG usage precluded any drawing of conclusion on the potential role of IVIG in the prevention of peritonitis.

CONCLUSIONS

Hypogammaglobulinemia is a frequent complication of CPD during infancy. In our experience, it was not associated with an increased risk for peritonitis.

Vaccine-preventable infection morbidity of patients with chronic kidney disease and cocoon vaccination strategies

Individuals with chronic kidney disease (CKD) are vulnerable to vaccine-preventable infections due to impaired immunity, immunosuppressive treatments and dialysis. Protection of CKD patients by vaccination is hampered by reduced efficacy of vaccines and safety concerns for transplant candidates or recipients. 'Cocooning' vaccination policies, targeting the protection of a vulnerable individual through immunization of close contacts, have recently been introduced for infants and, to a lesser degree, for high-risk groups of immunocompromised individuals. In this article, we discuss the potentiality of implementing cocoon strategies for the high-risk group of CKD patients and conclude that this not yet officially recommended policy can substantially contribute to protection against infection and motivate vaccination among families and healthcare workers.

Serum immunoglobulin G levels and peritonitis in peritoneal dialysis patients

BACKGROUND

Peritonitis is a frequent and serious complication of peritoneal dialysis (PD). Whether low immunoglobulin level is associated with PD-related peritonitis is unknown.

METHODS

We conducted a prospective study to assess whether immunoglobulin levels at PD onset could predict the occurrence of peritonitis. All patients starting peritoneal dialysis between 01/2005 and 12/2010 at the University hospital of Besançon, France, were included in the study.

RESULTS

Of 240 consecutive PD patients enrolled (mean follow-up 25 ± 12 months), 76 (32%) had at least one episode of peritonitis. Mean immunoglobulin (Ig)G level at PD start was lower in patients who subsequently experienced peritonitis (7.9 + 3.4 vs. 9.7 + 3.4 g/l, p = 0.005). An increased IgG level at PD onset was associated with a reduced risk of peritonitis [hazard ratio (HR) 0.88, 95% confidence interval (CI) 0.80-0.97 for each increase of 1 g/l in IgG, p = 0.008]. IgG level ≤6.4 g/l ("low IgG") was the best predictive value for the occurrence of subsequent peritonitis: 52 patients (24%) had low IgG levels. At multivariate analysis, both low IgG level (HR 2.49, 95% CI 1.32-4.69, p = 0.005) and diabetes (HR 2.78, 95% CI 1.49-5.20, p = 0.001) were predictive of the occurrence of peritonitis.

CONCLUSION

Low IgG levels predict the occurrence of PD-related peritonitis. Randomized studies should determine whether such patients could benefit from intravenous immunoglobulin administration.

Immune cell dysfunction and inflammation in end-stage renal disease

Uraemia causes inflammation and reduces immune system function as evidenced by an increased risk of viral-associated cancers, increased susceptibility to infections and decreased vaccination responses in patients with end-stage renal disease (ESRD). The substantially increased risk of atherosclerosis in these patients is also probably related to uraemia-associated inflammation. Uraemia is associated with a reduction in the number and function of lymphoid cells, whereas numbers of myeloid cells in uraemic patients are normal or increased with increased production of inflammatory cytokines and reactive oxygen species. Similar to healthy elderly individuals, patients with ESRD have increased numbers of specific proinflammatory subsets of T cells and monocytes, suggesting the presence of premature immunological ageing in these patients. These cells might contribute to inflammation and destabilization of atherosclerotic plaques, and have, therefore, been identified as novel nonclassical cardiovascular risk factors. The cellular composition of the immune system does not normalize after successful kidney transplantation despite a rapid reduction in inflammation and oxidative stress. This finding suggests that premature ageing of the immune system in patients with ESRD might be related to a permanent skewing of the haematopoetic stem cell population towards myeloid-generating subsets, similar to that seen in healthy elderly individuals.

Immunogenicity of meningococcus C vaccination in a patient with atypical hemolytic uremic syndrome (aHUS) on eculizumab therapy

We report successful kidney transplantation in a 10-yr-old boy with aHUS and heterozygous factor H mutation using the terminal complement inhibitor eculizumab to avoid recurrence of aHUS in the renal graft. Vaccination against meningococcus C (Men C) is essential in patients with dysfunction of the complement system, as induced by eculizumab. In our patient, we report waning SBA titers but maintenance of protective SBA titers (≥1:8) after kidney transplantation under immunosuppressive therapy with mycophenolate mofetil, tacrolimus, steroids, and eculizumab over a 27-month observational period. Our case illustrates that a humoral immune response to conjugate Men C vaccination may be mounted and maintained despite chronic renal disease, kidney transplantation, immunosuppressive drugs, and immunomodulatory therapy with eculizumab. However, it remains unclear whether serologically defined protective SBA titers mediate true protection from invasive meningococcal disease in an immunocompromised patient, particularly under treatment with a complement inhibitor. Thus, close monitoring of SBA titers seems mandatory in this patient.

A comparison of herpes zoster incidence across the spectrum of chronic kidney disease, dialysis and transplantation

BACKGROUND

The effect of different renal replacement therapies on the risk of developing herpes zoster in renal failure patients is unknown. We aimed to investigate the incidence of herpes zoster attack among renal failure patients who were receiving different dialysis modalities, renal transplantation (RT), or not receiving any of the above mentioned therapies yet.

METHODS

A retrospective cohort study of the national health insurance register database was conducted. This observational cohort study involved 79,581 study controls, 15,802 chronic kidney disease patients, 3,694 hemodialysis (HD) patients, 317 peritoneal dialysis (PD) patients, and 159 RT patients.

RESULTS

The RT group had the worst risk of herpes zoster (hazard ratio, HR, 8.46; 95% CI 5.85-12.2), followed by PD (HR 3.61; 95% CI 2.49-4.83) and HD (HR 1.35; 95% CI 1.18-1.55), compared with the comparison group (p < 0.0001). The RT group had also the highest risk of developing herpes zoster with complications among all groups (adjusted HR 15.3). The HRs of the PD group were higher than the HRs of the HD group in terms of herpes zoster or its complications (p < 0.0001 and p = 0.0002, respectively).

CONCLUSIONS

This study suggests that different treatment modalities are associated with different risks of herpes zoster attacks in renal failure patients. PD patients had higher risks than the HD group in terms of herpes zoster or its complications.

Comparison of hepatitis B surface antibody decay rates after vaccination between hemodialysis and peritoneal dialysis patients

BACKGROUND AND OBJECTIVES

The available information about maintaining effective immunity after hepatitis B virus (HBV) vaccination in dialysis patients is limited. The aim of this study was to determine whether a difference exists in the persistence of immunity between hemodialysis (HD) and peritoneal dialysis (PD) patients. We compared the decay rate of hepatitis B surface antibody (anti-HBs) titers after HBV vaccination between HD and PD patients.

DESIGN, SETTING, PARTICIPANTS, AND MEASURES

A total of 103 HD and 53 PD patients who were completely vaccinated were enrolled. We examined their anti-HBs titers at the 1st month after vaccination then annually thereafter. Changes in the anti-HBs titers were assessed by comparing annual geometric mean titers (GMTs).

RESULTS

The slopes of the anti-HBs titer decay rates plotted on a logarithmic scale for the HD and PD groups were -23.41 and -31.48, respectively. The decay rate of the PD group was significantly faster than that of the HD group (P=0.0053).

CONCLUSION

The decay rate of anti-HBs titers in the PD group was faster than that in the HD group. Hepatitis B vaccination could not offer long-term protection in HD or PD patients. Post-vaccination testing every 6-12 months is necessary and revaccination may be protective in dialysis patients, especially in hyper-endemic areas of hepatitis B infection.

Dialysis-associated peritonitis in children

Peritonitis remains a frequent complication of peritoneal dialysis in children and is the most common reason for technique failure. The microbiology is characterized by a predominance of Gram-positive organisms, with fungi responsible for less than 5% of episodes. Data collected by the International Pediatric Peritonitis Registry have revealed a worldwide variation in the bacterial etiology of peritonitis, as well as in the rate of culture-negative peritonitis. Risk factors for infection include young age, the absence of prophylactic antibiotics at catheter placement, spiking of dialysis bags, and the presence of a catheter exit-site or tunnel infection. Clinical symptoms at presentation are somewhat organism specific and can be objectively assessed with a Disease Severity Score. Whereas recommendations for empiric antibiotic therapy in children have been published by the International Society of Peritoneal Dialysis, epidemiologic data and antibiotic susceptibility data suggest that it may be desirable to take the patient- and center-specific history of microorganisms and their sensitivity patterns into account when prescribing initial therapy. The vast majority of patients are treated successfully and continue peritoneal dialysis, with the poorest outcome noted in patients with peritonitis secondary to Gram-negative organisms or fungi and in those with a relapsing infection.

Demand for evaluation of vaccination antibody titers in children considered for renal transplantation

Vaccinations are recommended for achieving protection against vaccine-preventable infections in solid-organ transplant recipients. In order to evaluate the protection at the time of renal transplantation, the antibody titers against measles, mumps, rubella, varicella, hepatitis B, diphtheria, and tetanus were determined in 35 children one month prior to transplantation. Only 26% of patients on dialysis listed for transplantation showed protective antibodies against all tested pathogens. Particularly, low protection was found for hepatitis B. Children younger than four yr showed significantly lower protective antibody titers compared with older children for almost all vaccines. Children who completed vaccination in the last six months to six yr prior to renal transplantation showed higher rates of protective antibody titers against all pathogens compared with children who had vaccination more than six yr before transplantation. Preventive strategies in children with chronic renal failure include repeated measurements of serum antibodies and appropriate revaccination if titers decline. Our results underline the demand for continuous surveillance of specific antibody titers against vaccine-preventable diseases in the risk group of renal transplant recipients.

Immunization in children with chronic renal failure: a practical approach

The prevention of systemic viral and bacterial infections by effective vaccination represents an essential task of pediatric nephrologists caring for children with chronic renal failure (CRF) undergoing renal transplantation (RTPL) with life-long immunosuppression. This review addresses three issues: risk of vaccine-preventable diseases, safety, immunogenicity, and clinical efficacy of available vaccines, and implementation of immunization guidelines. Infections (including vaccine-preventable infections) represent the leading cause of morbidity and mortality in children on dialysis and after RTPL. Vaccination in children with CRF and after RTPL is safe and does not cause reactivation of an immune-related renal disease or rejection after RTPL. Children with CRF generally produce protective serum antibodies to primary vaccinations with killed or component vaccines and live virus vaccines; some children on dialysis and after RTPL may not respond optimally, requiring repeated vaccination. Proof of vaccine efficacy is absence of disease, which can only be confirmed in large cohort studies. A few observational studies provide evidence that vaccination has contributed significantly, at least in the western hemisphere, to the low prevalence of vaccine-preventable diseases among children with CRF. Close cooperation between the local pediatrician/practitioner and the pediatric nephrologist is essential for successful implementation of the vaccination schedule.

Children with chronic renal failure have reduced numbers of memory B cells

Reduced serum IgG and subclass levels have been demonstrated in children with chronic renal failure. To study possible causes of this reduction, we analysed B cell subset composition, T helper cell frequencies and immunoglobulin (Ig) production capacity in vitro in children with chronic renal failure, with or without dialysis treatment. B cell subsets were characterized by determining CD27, IgM, IgD and CD5 expression within the CD19(+) population. Intracellular expression of interferon (IFN)-gamma, interleukin (IL)-2 and IL-4 in PMA/ionomycin-stimulated peripheral blood mononuclear cells (PBMC) was used to evaluate T helper frequencies. The capacity of B cells to secrete Ig in vitro was determined by measuring IgG(1), IgG(2) and IgM in culture supernatants of anti-CD2/CD28 monoclonal antibody (MoAb)- or SAC/IL-2-stimulated PBMC. Memory B cell numbers (identified as percentage or absolute number of CD19(+) IgM-IgD- or CD19(+)CD27(+) lymphocytes) were lower in children treated with haemodialysis (HD), peritoneal dialysis (PD) and children with chronic renal failure before starting dialysis treatment (CRF) compared to healthy controls (HC) (P < 0.05). Compared with HC, CD5(+) (naive) B cells were reduced in HD-treated patients but not for PD or for children with chronic renal failure before starting dialysis treatment (CRF). No significant differences in CD4(+) T helper cell subsets were found between the groups. However, CRF children had a higher percentage of IFN-gamma producing CD8(+) T lymphocytes compared to HC (P = 0.02). Finally, IgG(1), IgG(2) and IgM production in vitro was similar in the four groups. In conclusion, significantly lower numbers of memory type B cells were found in children with chronic renal failure compared to healthy controls. This reduction may contribute to the low Ig levels found in these children.

IGG and complement receptor expression on peripheral white blood cells in uraemic children

BACKGROUND

Phagocytosis of IgG- or complement-opsonized bacteria and antibody production by lymphocytes are regulated by cell surface receptors for IgG (FcgammaRI, FcgammaRII and FcgammaRIII) and complement (CR1 and CR3). We measured the effect of uraemia and dialysis treatment on FcgammaR and CR expression on leukocytes in blood.

METHODS

Blood samples were obtained from children: 40 treated with peritoneal dialysis (PD), 23 with haemodialysis (HD), 46 not yet dialysed (CRF) and 33 healthy (HC). White blood cells, isolated from EDTA-blood by centrifugation after cell fixation with paraformaldehyde, were labelled with FITC-conjugated CD16 (FcgammaRIII), CD32 (FcgammaRII), CD64 (FcgammaRI), CD11b (CR3) and CD35 (CR1) monoclonal antibodies and analysed by flow cytometry.

RESULTS

In PD, HD, CRF and HC, monocytes and neutrophils were all positive for FcgammaR and CR, except for CD16 on monocytes (20% positive). Lymphocytes expressed CD16 and CD32 but not CD64. PD, HD and CRF children had lower percentages of CD16(+) and CD32(+) lymphocytes compared with HC. The percentage of CD11b(+) lymphocytes was lower only in PD and the percentage of CD35(+) lymphocytes was lower in HD and CRF compared with HC. The median CD32 mean fluorescense intensity (MFI) on lymphocytes, monocytes and neutrophils was lower in PD, HD and CRF compared with HC. On the other hand, CD11b MFI on lymphocytes, monocytes and neutrophils was higher in PD, HD and CRF children compared with HC. CD16 and CD64 MFI were not different among the groups and CD35 MFI was only lower on lymphocytes from PD, HD and CRF compared with HC.

CONCLUSIONS

In children with chronic renal failure, whether dialysed or not, FcgammaRII expression on lymphocytes, monocytes and neutrophils was reduced and CR3 expression was increased. Furthermore, CR1 expression on lymphocytes, important for the humoral response, was lower in children with renal failure. Age and uraemia are associated with these abnormalities and might contribute to impaired immune function in children with chronic renal failure.

Management of peritonitis in children receiving chronic peritoneal dialysis

Bacterial peritonitis is a major threat to long-term peritoneal membrane function in pediatric patients receiving chronic peritoneal dialysis (CPD). This review summarizes the demographics, risk factors, and current recommendations regarding diagnostic procedures, management, and prevention of peritonitis in children. Albeit decreasing in incidence, bacterial peritonitis remains a major cause of technique failure in children with endstage renal disease receiving CPD. The use of standardized diagnostic procedures, efficacious antibacterial treatment, and objective response criteria are crucial in improving the outcome of this complication. Current guidelines recommend combining a first- and third-generation cephalosporin for empiric therapy in uncomplicated cases. The initial use of a glycopeptide/third-generation cephalosporin combination should be restricted to patients with risk factors for severe disease, as defined by clinical presentation, young age (<2 years), and recent infection with a methicillin resistant micro-organism. Several risk factors for primary or relapsing peritonitis have been identified, some of which are amenable to preventive measures. These relate to catheter design and implantation technique, connection methodology, early catheter removal in refractory or relapsing peritonitis, and eradication of Staphylococcus aureus from the catheter exit site and/or nasal reservoirs in patients and their caregivers.