Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0024141 (systemic lupus erythematosus)
 44,322 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

C1q deposits are usually found in association with other complement components and immunoglobulins in proliferative glomerulonephritis and may predominate in systemic lupus erythematosus (SLE). We report the clinical outcome of four patients who developed a nephrotic syndrome associated with C1q nephropathy unrelated to SLE. On presentation the mean urinary protein loss was 6.8 g/24 h (range 4-10), and renal function impaired, mean serum creatinine 201 mumol/l (150-400). Over a mean follow up period of 6.5 years (1.7-19), all four patients improved, three spontaneously and one treated with steroids and cyclosporin, to a current urinary protein loss of 0.3 g/24 h (less than 0.2-0.9) and serum creatinine 98 mumol/l (68-115). C1q nephropathy was confirmed in each biopsy by conventional immunohistology. C1q deposits were demonstrated within the glomerular basement membrane of three biopsies and the mesangium in two samples. One patient had been categorized on light- and electron-microscopy as having mesangiocapillary glomerulonephritis, one membranous glomerulonephritis, one proliferative glomerulonephritis with focal segmental glomerulosclerosis, and one diffuse proliferative glomerulonephritis with both subendothelial and mesangial dense deposits. In view of the expected progressive nature of the underlying renal histopathological appearance, the presence of predominant C1q deposits would appear to be associated with a better clinical outcome.
 ...
PMID:C1q nephropathy: do C1q deposits have any prognostic significance in the nephrotic syndrome? 132 73

The presence, distribution, and intensity of glomerular C1q localization were evaluated by direct immunofluorescence microscopy in 800 renal biopsy specimens which were also studied by light and electron microscopy. Identified were 15 patients with extensive (mean: 3.6 + out of 4 +), predominantly mesangial, C1q localization along with C3 and immunoglobulins, but no evidence for systemic lupus erythematosus. Pathologically, this lesion most closely resembled lupus nephritis. Clinical and pathologic data from these 15 C1q nephropathy patients were compared to data from 30 lupus nephritis and 223 other proliferative glomerulonephritis patients, and the C1q nephropathy patients were found to be dissimilar to both groups. The 15 C1q nephropathy patients had an average age of 17.8 years, 8 males, 7 females, 9 Black, 100% had proteinuria (mean 7.5 g/d), 40% hematuria, 0% hypocomplementemia, and 0% antinuclear antibodies. By electron microscopy, 100% had mesangial dense deposits, 20% capillary wall dense deposits, and 0% endothelial tubuloreticular inclusions. Nine patients treated with steroids had no definite resolution of proteinuria. We proposed that C1q nephropathy is a distinct clinicopathologic entity, usually causing steroid-resistant nephrotic syndrome in older children and young adults.
 ...
PMID:C1q nephropathy: a distinct pathologic entity usually causing nephrotic syndrome. 387 86

C1q nephropathy is an immune complex glomerulonephritis defined by the presence of mesangial immunoglobulins and complement deposits, most notably C1q, and the absence of clinical and laboratory evidence of systemic lupus erythematosus. Histology in C1q nephropathy is characterized by a slight to severe increase in mesangial cellularity and matrix, with or without segmental sclerosis. C1q nephropathy usually presents with nephrotic-range proteinuria in older children and young adults, and has a poor response to steroids. Patients may have decreased creatinine clearance at presentation, but progression to end-stage renal disease (ESRD) is slow. Severe crescentic glomerulonephritis has not been reported in C1q nephropathy. We describe a 3-year-old Hispanic girl who presented with renal insufficiency. Kidney biopsy showed C1q nephropathy with severe crescentic glomerulonephritis. The clinical and serological evaluation ruled out systemic lupus erythematosus or other immunological or infectious etiologies. In spite of immunosuppressive therapy, she progressed to ESRD within 14 weeks and is currently on chronic peritoneal dialysis. The atypical features of C1q nephropathy observed in our patient, which have not been described in earlier reports, are an early age of onset, severe crescentic glomerulonephritis, and rapid progression to ESRD. C1q nephropathy should be added to the differential diagnosis of glomerulonephritis in young children and in the patient with crescentic glomerulonephritis.
 ...
PMID:C1q nephropathy presenting as rapidly progressive crescentic glomerulonephritis. 1097 10

C1q nephropathy is a distinct entity characterized by extensive and dominant C1q mesangial deposition with associated steroid resistant proteinuria in the absence of systemic lupus erythematosus. Several morphological patterns ranging from very subtle glomerular alterations to focal/segmental glomerulosclerosis and mesangial proliferative changes have been described. Interstitial nephritis secondary to BK polyomavirus is a recently recognized complication in kidney transplant recipients. It may be associated with a tubulitis-like picture, mimicking sometimes acute tubular rejection. We report the case of a kidney pancreas transplant recipient who developed de novo C1q nephropathy, in the setting of BK polyomaviral interstitial nephritis. He presented with renal allograft dysfunction and a kidney biopsy was performed. It was interpreted as acute cellular rejection. C1q deposits were detected by immunofluorescence studies and electron microscopy. The patient did not respond clinically to appropriate anti-rejection treatment and a second renal biopsy was performed. The possibility of an interstitial nephritis secondary to BK polyomavirus mimicking rejection was suggested. Special immunohistochemical and blood/urine PCR studies for BK virus were performed, confirming the diagnosis of BK virus tubulonterstitial nephritis with a persistent, probable BK virus induced C1q nephropathy.
 ...
PMID:De novo C1q nephropathy in the renal allograft of a kidney pancreas transplant recipient: BK virus-induced nephropathy? 1221 24

The study population comprised all 20 patients followed since 1990 through December 2004 at the Le Bonheur Children's Medical Center with diagnosis of C1q nephropathy (55% boys; 60% African Americans). All were aged under 18 years at biopsy (mean 11.2 years, 65% aged 11 or over); the youngest presented at age 10 months and progressed to end-stage renal disease at 14 months. None had clinical or laboratory features of systemic lupus erythematosis or membranoproliferative glomerulonephritis. Clinical features assessed at diagnosis were age, gender, blood pressure, history of macroscopic hematuria, urinary protein to creatinine ratio, serum creatinine, estimated glomerular filtration rate, renal histology, and pattern for immunofluorescent reactants. At the time of biopsy 40% had nephrotic syndrome and 30% nephrotic range proteinuria without nephrotic syndrome. Three patients with nephrotic syndrome also had chronic renal insufficiency at diagnosis. The most common histological feature was focal segmental glomerulosclerosis in 40%, but 30% had minimal change lesion. Four patients, all with nephrotic syndrome at diagnosis, progressed to end-stage renal disease. Of the 12 patients not presenting with nephrotic syndrome, none had chronic renal insufficiency at last follow-up. Kidney survival was 94% and 78% at 1 and 5 years, respectively, in all patients and 88% and 49% in those presenting with nephrotic syndrome.
 ...
PMID:C1q nephropathy: features at presentation and outcome. 1613 42

C1q nephropathy (C1qNP) is a peculiar form of glomerulonephritis characterized by mesangial immunoglobulin and complement deposits, predominantly C1q, with no evidence of systemic lupus erythematosus. We describe the incidence, manifestation, histopathologic findings, follow-up, treatment and outcome of C1qNP. Twelve C1qNP patients were identified among 131 children who had undergone renal biopsy, accounting for a 9.16% incidence of C1qNP. Light microscopy examination showed focal segmental glomerulosclerosis (FSGS) with or without diffuse mesangial proliferation (n=6), minimal change disease (MCD) (n=4) or focal glomerulonephritis (n=2). C1q deposits were found in all, while electron microscopy revealed visible deposits in nine cases. Eight children presented with nephrotic syndrome, while one had nephrotic proteinuria and renal insufficiency that progressed to end-stage renal failure. The remaining three patients presented with nonnephrotic proteinuria associated with microhematuria, hypertension or renal insufficiency. Only one nephrotic syndrome patient responded excellently to corticosteroids, while four became corticosteroid dependent, and three were corticosteroid resistant, showing a very poor response to other immunosuppressive therapy as well. Patients with non-nephrotic proteinuria demonstrated fixed laboratory findings. Most C1qNP patients had FSGS or MCD, the majority of them presenting with corticosteroid-dependent or corticosteroid-resistant nephrotic syndrome. The latter showed a very poor response to any immunosuppressive therapy and high risk for progressive renal insufficiency.
 ...
PMID:C1Q nephropathy in children. 1624 48

C1q nephropathy (C1qNP) is a controversial and uncommon form of glomerulonephritis, characterized by mesangial immunoglobulin and complement deposits, predominantly C1q, with no evidence of systemic lupus erythematosus. Clinically, it may present as nephrotic syndrome and non-nephrotic proteinuria per se or associated with microhematuria, hypertension, or renal insufficiency. We describe two sisters with C1qNP, who presented with steroid-resistant nephrotic syndrome. Both sisters presented before the age of 2 years, and they showed a poor response to other immunosuppressive therapy. Both girls had normal serum complement levels, negative antinuclear antibodies (ANAs) and negative hepatitis B antigen. Renal biopsy in both patients showed histological features of mesangioproliferative glomerulonephritis, with diffuse "full-house" positive immunofluorescence reaction in the mesangial area. The immunofluorescence reaction for C1q was most intense and co-dominant with IgG in both patients. Correspondingly, electron microscopy demonstrated dense deposits mainly in the mesangial areas too. We report on two young sisters with the characteristic features of C1qNP presented in early childhood. To the best of our knowledge, this is the first report of C1qNP in siblings.
 ...
PMID:C1q nephropathy in two young sisters. 1795 93

C1q nephropathy, first proposed by Jennette and Hipp [Am J Clin Pathol 83:415-420, 1985; Am J Kidney Dis 6:103-110, 1985], was described as a distinct glomerular disease entity characterized by extensive mesangial deposition of C1q, with associated mesangial immune complexes, and the absence of any clinical and laboratory evidence of systemic lupus erythematosus. Now, 20 years since the first report, the disease entity is gradually attaining recognition, particularly in the field of pediatrics. C1q is the subcomponent of C1 in the classical pathway of complement activation. Generally, C1q deposition is caused by the activation of C1 by immunoglobulin G (IgG) and IgM; therefore, C1q nephropathy is considered as an immune complex glomerulonephritis. However, in C1q nephropathy, it remains unclear whether the deposition of C1q in the glomeruli is in response to the deposition of immunoglobulin or immune complex, or whether deposition is non-specific trapping that accompanies increased glomerular protein trafficking associated with proteinuria. Since not only the pathogenesis of C1q deposition in glomeruli but also its significance are still uncertain, it has not yet been established as an independent disease. From recent publications of the clinical and pathological characterizations, C1q nephropathy has been thought to be a subgroup of primary focal segmental glomerular sclerosis. However, many reports describe different symptoms, histopathologies, therapeutic responses and prognoses, suggesting that C1q nephropathy is not a single disease entity, but that it may be a combination of several disease groups. There are many uncertain areas requiring further investigation, though it is hoped that a detailed examination of future cases will clarify the subgroups making up C1q nephropathy and their clinicopathological characteristics, and will lead to the establishment of C1q nephropathy as an independent disease entity.
 ...
PMID:Current status and issues of C1q nephropathy. 1937 20

Steroid resistant nephrotic syndrome (SRNS) remains a challenge facing pediatric nephrologists. The underlying histopathology usually affects the course of the disease and the response to treatment. We studied the pattern of histopathology in children with SRNS who presented to the King Abdul Aziz University Hospital (KAUH), Jeddah, Saudi Arabia. The records of all children with primary SRNS, who were seen between 2002 and 2007 were reviewed. Only patients who had undergone a renal biopsy were included in the study. The histopathology slides were reviewed by two renal pathologists independently. Patients with congenital nephrotic syndrome, lupus or sickle cell disease, were excluded from the study. Thirty-six children fulfilled the inclusion criteria, and included 25 girls and 11 boys with female to male ratio of 2.3:1. Fifty percent of the children (n=18) were Saudi and the remaining 50% were from various other racial backgrounds (9 Asians, 4 Arabs, 2 Africans and 3 from the Far East). Their mean age at presentation was 4.3 +/- 3.0 years (range 1-12 years). The mean serum albumin at presentation was 15.6 +/- 7.1 g/L and all of them had 4+ proteinuria on urinalysis. Five children had elevated serum creatinine at presentation while the mean serum creatinine was 50.4 +/- 45.6 micromol/L. Three children had low serum complement levels at presentation and none were positive for hepatitis B surface antigen or antinuclear antibody (ANA). The renal histopathology was compatible with focal and segmental glomerulosclerosis (FSGS) in 39% (n=14), IgM nephro-pathy in 28% (n=10), mesengioproliferative glomerulonephritis (MesPGN) in 17% (n=6), mini-mal change disease (MCD) and C1q nephropathy (C1qNP) in 8% each (n=3 + 3) and IgA nephro-pathy in 3% (n=1). Our retrospective review shows that FSGS was the commonest underlying histopathology in children who presented with SRNS followed by IgM nephropathy and other variants of MCD such as MesPGN. C1qNP was the underlying cause in some children.
 ...
PMID:Pattern of steroid resistant nephrotic syndrome in children living in the kingdom of Saudi Arabia: a single center study. 1973 91

We report the outcome of our single-center, long-term follow-up study of tacrolimus therapy in children with steroid-resistant nephrotic syndrome (SRNS). All cases of nephrotic syndrome (NS) with kidney biopsies treated at our center between January 2000 and July 2008 were reviewed. Children with systemic lupus erythematosus and steroid-dependent NS were excluded. Nineteen children with SRNS received tacrolimus. Histopathological analysis of the biopsy revealed the underlying conditions of these 19 patients to be focal segmental glomerulosclerosis (ten patients), C1q nephropathy (four), membranous nephropathy (two), minimal change disease (one), membranoproliferative glomerulonephritis (one), and immunoglobulin A nephropathy (one). The mean follow-up was 55 months, and the median age of the patient cohort was 10 years. We observed complete remission in 11 (58%) patients, partial remission in six (32%), and failure to respond in two (9%). The median time to response was 8 weeks. Side effects were mild and transient (one case of acute kidney injury and three cases of hyperglycemia). The initial rate for combined partial and complete remission of the NS in children with SRNS was 81%, which was sustained in 58% of the patients on follow-up. Among children with FSGS, the sustained remission rate was 50%, while 40% progressed to end-stage renal disease (ESRD) (mean time 52 months). Based on the results of this study, we conclude that tacrolimus is an effective and well-tolerated therapeutic option for the treatment of SRNS in children. However, the occurrence of relapses of the NS with progression to ESRD during the long-term follow-up indicates the need for careful monitoring of such patients.
 ...
PMID:Long-term outcome of children with steroid-resistant nephrotic syndrome treated with tacrolimus. 2021 33


1 2 3 Next >>