Pediatric lupus nephritis / Nefrite lúpica em pediatria

Abstract Involvement of the kidneys by lupus nephritis (LN) is one of the most severe clinical manifestations seen in individuals with systemic lupus erythematosus (SLE). LN is more frequent and severe in pediatric patients and has been associated with higher morbidity and mortality rates. This narrative review aimed to describe the general aspects of LN and its particularities when affecting children and adolescents, while focusing on the disease's etiopathogenesis, clinical manifestations, renal tissue alterations, and treatment options.

Resumo A nefrite lúpica (NL) é caracterizada pelo acometimento dos rins no contexto das diversas manifestações clínicas do Lupus Eritematoso Sistêmico (LES), e representa uma das manifestações clínicas mais graves da doença. A NL é mais frequente e mais grave nos pacientes pediátricos, em comparação com os adultos, e causa maiores taxas de morbidade e mortalidade. O objetivo desta revisão narrativa foi descrever os aspectos gerais da NL e suas particularidades em crianças e adolescentes, com foco em sua etiopatogênese, nas manifestações clínicas, nas alterações histopatológicas renais e na abordagem terapêutica.

Pediatric lupus nephritis.

Involvement of the kidneys by lupus nephritis (LN) is one of the most severe clinical manifestations seen in individuals with systemic lupus erythematosus (SLE). LN is more frequent and severe in pediatric patients and has been associated with higher morbidity and mortality rates. This narrative review aimed to describe the general aspects of LN and its particularities when affecting children and adolescents, while focusing on the disease's etiopathogenesis, clinical manifestations, renal tissue alterations, and treatment options.

Mesangial C4d deposition may predict progression of kidney disease in pediatric patients with IgA nephropathy.

BACKGROUND: Data on the risk factors for chronic kidney disease in children with immunoglobulin A nephropathy (IgAN) are scarce. This study was aimed at investigating whether glomerular C4d immunostaining is a prognostic marker in pediatric IgAN. METHODS: In this retrospective cohort study, 47 patients with IgAN biopsied from 1982 to 2010 were evaluated. Immunohistochemistry for C4d was performed in all cases. For analysis, patients were grouped according to positivity or not for C4d in the mesangial area. Primary outcome was a decline in baseline estimated glomerular filtration rate (eGFR) by 50% or more. RESULTS: Median follow-up was 8.3 years. Median renal survival was 13.7 years and the probability of a 50% decline in eGFR was 13% over 10 years. Nine children exhibited the primary outcome and 4 developed end-stage renal disease (ESRD). Compared with C4d-negative patients (n = 37), C4d-positive patients (n = 10) presented higher baseline proteinuria (1.66 ± 0.68 vs 0.47 ± 0.19 g/day/1.73 m2, p < 0.001), a progressive decline in eGFR (−10.04 ± 19.38 vs 1.70 ± 18.51 ml/min/1.73 m2/year; p = 0.045), and more frequently achieved the primary outcome (50.0 vs 10.8%, p = 0.013), and ESRD (30.0 vs 2.7%, p = 0.026). No difference was observed in Oxford classification variables. Baseline proteinuria, endocapillary hypercellularity and mesangial C4d deposition were associated with primary outcome in univariate analysis. Proteinuria and mesangial C4d deposition at baseline independently predicted the decline in eGFR. Renal survival was significantly reduced in C4d-positive patients (8.6 vs 15.1 years in C4d-negative patients, p < 0.001). CONCLUSIONS: In this exclusively pediatric cohort, positivity for C4d in the mesangial area was an independent predictor of renal function deterioration in IgAN.

Immunoglobulin a nephropathy: Pathological markers of renal survival in paediatric patients.

IgA nephropathy (IgAN) is one of the leading causes of glomerulonephritis characterized by the findings of IgA and IgG immune deposits in the mesangium of kidney biopsies from patients with persistent microscopic haematuria. IgAN is frequently detected among adolescents and young adults. IgAN presents a highly variable course that includes a spectrum from a very mild disease to end-stage renal disease (ESRD). There are several clinical and histological factors that strongly determined the final outcome of patients with IgAN. Pathological variables associated with unfavorable outcomes are mesangial hypercellularity, segmental glomerulosclerosis, endocapillary hypercellularity and interstitial fibrosis/tubular atrophy, according to the Oxford classification. Moreover, some studies also suggest a role for complement activation in the pathogenesis of IgAN. In this regard, staining for C4d may be an independent risk factor for the development of ESRD in IgAN. Despite the growing number of studies assessing IgAN risk factors, this kind of investigation in paediatric patients is still very limited. The aim of this article is to revise pathological markers related to deterioration of renal function in paediatric patients with IgAN, particularly those that can independently affect renal survival.

Immunoglobulin A nephropathy: a pathophysiology view.

BACKGROUND AND AIM: IgA nephropathy is one of the leading causes of primary glomerulonephritis worldwide and an important etiology of renal disease in young adults. IgA nephropathy is considered an immune complex-mediated disease. METHODS: This review article summarizes recent evidence on the pathophysiology of IgA nephropathy. RESULTS: Current studies indicate an ordered sequence of multi-hits as fundamental to disease occurrence. Altered glycan structures in the hinge region of the heavy chains of IgA1 molecules act as auto-antigens, potentially triggering the production of glycan-specific autoantibodies. Recognition of novel epitopes by IgA and IgG antibodies leads to the formation of immune complexes galactose deficient-IgA1/anti-glycan IgG or IgA. Immune complexes of IgA combined with FcαRI/CD89 have also been implicated in disease exacerbation. These nephritogenic immune complexes are formed in the circulation and deposited in renal mesangium. Deposited immune complexes ultimately induce glomerular injury, through the release of pro-inflammatory cytokines, secretion of chemokines and the resultant migration of macrophages into the kidney. The TfR1/CD71 receptor has a pivotal role in mesangial cells. New signaling intracellular mechanisms have also been described. CONCLUSION: The knowledge of the whole pathophysiology of this disease could provide the rational bases for developing novel approaches for diagnosis, for monitoring disease activity, and for disease-specific treatment.

Progressive multifocal leukoencephalopathy as an AIDS-defining condition in a patient with high CD4+ T-lymphocyte count.

We present the case of a 31-year-old man with acute manifestation of progressive multifocal leukoencephalopathy (PML) as an AIDS-defining disease. The patient presented with a three-day history of neurological disease, brain lesions without mass effect or contrast uptake and a slightly increased protein concentration in cerebrospinal fluid. A serological test for HIV was positive and the CD4+ T-cell count was 427/mm³. Histological examination of the brain tissue revealed abnormalities compatible with PML. The disease progressed despite antiretroviral therapy, and the patient died three months later. PML remains an important cause of morbidity and mortality among HIV-infected patients.

Progressive multifocal leukoencephalopathy as an AIDS-defining condition in a patient with high CD4+ T-lymphocyte count / Leucoencefalopatia multifocal progressiva como condição definidora de AIDS em paciente com contagem alta de linfócitos T CD4

We present the case of a 31-year-old man with acute manifestation of progressive multifocal leukoencephalopathy (PML) as an AIDS-defining disease. The patient presented with a three-day history of neurological disease, brain lesions without mass effect or contrast uptake and a slightly increased protein concentration in cerebrospinal fluid. A serological test for HIV was positive and the CD4+ T-cell count was 427/mm³. Histological examination of the brain tissue revealed abnormalities compatible with PML. The disease progressed despite antiretroviral therapy, and the patient died three months later. PML remains an important cause of morbidity and mortality among HIV-infected patients.

Apresentamos o caso de um homem de 31 anos com leucoencefalopatia multifocal progressiva (LMP) de manifestação aguda como doença definidora de AIDS. O paciente apresentou-se com doença neurológica com três dias de evolução, lesões encefálicas sem efeito de massa ou captação de contraste e leve aumento de proteínas no líquor. Sorologia para o HIV foi positiva e a contagem de linfócitos T CD4+ era de 427/mm³. O exame histológico de tecido cerebral revelou alterações compatíveis com LMP. A doença progrediu a despeito da terapia antirretroviral, e o paciente morreu após três meses. LMP permanece como causa relevante de mortalidade e morbidade em pacientes infectados pelo HIV.