Hepatitis B surface antigenaemia and glomerulopathies in children

Vaccine administration in children with chronic kidney disease

Pediatric patients with severe chronic kidney disease (CKD) on conservative treatment, on dialysis, and those with renal transplantation are at a higher risk for infectious diseases as the result of impaired immune responses against infectious agents. Infections in these patients can have drastic consequences for disease morbidity and mortality. Immunization is a crucial preventive strategy for disease management in this pediatric population. However, vaccination coverage among children with CKD remains low due to safety concerns and doubts about vaccine immunogenicity and efficacy. In this study, we reviewed why children with CKD are at higher risk of infections, the importance of vaccinations among these children, barriers to vaccinations, and recommend the best vaccination schedules. Overall, vaccines have acceptable immunogenicity, efficacy, and safety profiles in children with CKD. However, in some cases, the protective antibody levels induced by vaccines and the benefits and risks of booster vaccine doses must be individually managed. Furthermore, close contacts and household members of these children should complete age-appropriate vaccination schedules to increase the child's indirect protection.

Hepatitis B virus vaccination in children with steroid sensitive nephrotic syndrome: immunogenicity and safety?

We investigated the efficacy and safety of Hepatitis B vaccine (HBVac) in steroid sensitive nephrotic syndrome (SSNS) children. 41 patients with SSNS and 30 controls were vaccinated with HBVac(Engerix B(®)). Patients were divided into 3 subgroups:full dose steroid users, alternate-day steroid users and steroid non-users. Seroconversion rate was lower in steroid users than non-users at the 6th(p=0.015) and 12th(p=0.036) months. Antibody to Hepatitis B surface antigen(HBsAb) titers were significantly different between subgroups and controls at the 15th month. However, HBsAb and response rates were not different between subgroups at the 12th and 15th months (p>0.05). Five patients were unresponsive to HBVac. Relapse rates after the vaccination were higher than those in the prevaccination period (p=0.002). HBVac is less effective in producing immune response in SSNS children with steroid therapy. HBVac may trigger relapse in some patients. We recommend HBVac to SSNS children with low dose steroid therapy or after steroids are discontinued.

Extrarenal complications of the nephrotic syndrome

The systemic complications of nephrotic syndrome are responsible for much of the morbidity and mortality seen with this condition. This review discusses the causes for the hypoalbuminemia and the associated metabolic abnormalities of the nephrotic syndrome. No unifying hypothesis exists for the induction, maintenance, and resolution of nephrotic edema. In view of the wide spectrum of renal diseases leading to the nephrotic syndrome, more than a single mechanism may be responsible for the renal salt retention in these diverse conditions. Although hypoalbuminemia may be important, especially when plasma oncotic pressure is very low (serum albumin < 1.5 to 2.0 g/dL), primary impairment of salt and water excretion by the nephrotic kidney appears to be a major factor in pathogenesis of the edema. However, the decreased serum albumin and/or oncotic pressure seen with nephrotic syndrome is a major contributing factor to the development of the hyperlipidemia of nephrotic syndrome. Patients with unremitting nephrotic syndrome should be considered for combined dietary and lipid-lowering drug therapy. Urinary losses of binding proteins lead to the observed abnormalities in the endocrine system and in trace metals, and urinary losses of coagulation factors contribute to the hypercoagulable state. At present, selective renal venography is recommended when the suspicion of renal vein thrombosis is justified by clinical presentation. The impact on renal function caused by treating asymptomatic chronic renal vein thrombosis is undetermined, but anticoagulation for chronic renal vein thrombosis is associated with relatively few complications.

Immunization practices in childhood nephrotic syndrome: a survey of North American pediatric nephrologists

The indications for immunizing children with minimal change nephrotic syndrome are a subject of some controversy, since it has been reported that immunization may not be effective or may serve as an immunogenic stimulus that precipitates an episode of relapse. To determine the current recommendations of practicing pediatric nephrologists, a questionnaire was sent to the members of the American Society of Pediatric Nephrology. Over half responded, and the results of the survey indicated that a consensus for approaching immunization does not exist. Further, little data are available to support any particular immunization practice. Several potential means to accumulate such data are outlined.

Reduced response to hepatitis B virus vaccination in boys with steroid-sensitive nephrotic syndrome

Vaccination against hepatitis B virus (HBV) was performed in 18 boys (aged 5.7 +/- 2.4 years) suffering from steroid-sensitive nephrotic syndrome (SSNS) and in a control group of 21 healthy boys (aged 5.6 +/- 3.8 years). The percentage of patients who responded to vaccination was significantly lower than the control group 1, 6, 8, 12, 18 and 24 months after the start of vaccination. The titre of antibodies to HBV surface antigen produced by responders at 6 and 24 months was significantly lower in patients than in the control group. Boys with SSNS have an impaired response to HBV vaccination.

Hepatitis B virus-associated glomerulonephritis: electron microscopic studies in 98 children

Ninety-eight children with glomerulonephritis concomitant with hepatitis B surface HBs antigenemia were studied, the antigenemia being first documented at the clinical onset of glomerulopathy. Initial diagnoses, based on examination of the paraffin sections, varied, membrano-proliferative, mesangial, and membranous glomerulonephritis being most frequently considered. However, electron microscopic examination showed that 77 children had a uniform type of glomerulopathy, irrespective of the light microscopic appearance. This type was diagnosed as secondary membranous glomerulonephritis. The clinical course of this nephropathy was relatively indolent and short. Moreover, in many children, elimination of some hepatitis B virus (HBV) antigens from the circulation was also associated with clinical remission of glomerulopathy. The remaining 21 children with HBs antigenemia had various morphological forms of glomerulonephritis, these being similar to their idiopathic counterparts in both morphology and clinical course. The distinct clinical and morphological picture of secondary membranous glomerulonephritis with HBs antigenemia occurring in 77 of 98 children supports the hypothesis that HBsV-associated glomerulonephritis is of the secondary membranous type. Thus, we conclude that in children HBV antigenemia associated with glomerulonephritis other than secondary membranous is coincidental.