Functional and morphologic evaluation of kidney proximal tubuli and correlation with renal allograft prognosis.

Renal transplant patients with stable graft function and proximal tubular dysfunction (PTD) have an increased risk for chronic allograft nephropathy (CAN). In this study, we investigated the histologic pattern associated with PTD and its correlation with graft outcome. Forty-nine transplant patients with stable graft function were submitted to a biopsy. Simultaneously, urinary retinol-binding protein (uRBP) was measured and creatinine clearance was also determined. Banff's score and semi-quantitative histologic analyses were performed to assess tubulointerstitial alterations. Patients were followed for 24.0 + or - 7.8 months. At biopsy time, mean serum creatinine was 1.43 + or - 0.33 mg/dl. Twelve patients (24.5%) had uRBP > or = 1 mg/l, indicating PTD and 67% of biopsies had some degree of tubulointerstitial injury. At the end of the study period, 18 (36.7%) patients had lost renal function. uRBP levels were not associated with morphologic findings of interstitial fibrosis and tubular atrophy (IF/TA), interstitial fibrosis measured by Sirius red or tubulointerstitial damage. However, in multivariate analysis, the only variable associated with the loss of renal function was uRBP level > or = 1 mg/l, determining a risk of 5.290 of loss of renal function (P = 0.003). Renal transplant patients who present PTD have functional alteration, which is not associated with morphologic alteration. This functional alteration is associated to progressive decrease in renal function.

Influence of muscle mass and physical activity on serum and urinary creatinine and serum cystatin C.

BACKGROUND AND OBJECTIVES: For addressing the influence of muscle mass on serum and urinary creatinine and serum cystatin C, body composition was assessed by skinfold thickness measurement and bioelectrical impedance analyses. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A total of 170 healthy individuals (92 women, 78 men) were classified as sedentary or with mild or moderate/intense physical activity. Blood, 24-h urine samples, and 24-h food recall were obtained from all individuals. RESULTS: Serum and urinary creatinine correlated significantly with body weight, but the level of correlation with lean mass was even greater. There was no significant correlation between body weight and lean mass with cystatin C. Individuals with moderate/intense physical activity presented significantly lower mean body mass index (23.1 +/- 2.5 versus 25.7 +/- 3.9 kg/m(2)) and higher lean mass (55.3 +/- 10.0 versus 48.5 +/- 10.4%), serum creatinine (1.04 +/- 0.12 versus 0.95 +/- 0.17 mg/dl), urinary creatinine (1437 +/- 471 versus 1231 +/- 430 mg/24 h), protein intake (1.4 +/- 0.6 versus 1.1 +/- 0.6 g/kg per d), and meat intake (0.7 +/- 0.3 versus 0.5 +/- 0.4 g/kg per d) than the sedentary individuals. Conversely, mean serum cystatin did not differ between these two groups. A multivariate analysis of covariance showed that lean mass was significantly related to serum and urinary creatinine but not with cystatin, even after adjustment for protein/meat intake and physical activity. CONCLUSIONS: Cystatin C may represent a more adequate alternative to assess renal function in individuals with higher muscle mass when mild kidney impairment is suspected.

Cryoglobulinemia in chronic hepatitis C: clinical aspects and response to treatment with interferon alpha and ribavirin.

INTRODUCTION: The main extra-hepatic manifestation of hepatitis C is mixed cryoglobulinemia (MC). The aim of this study was to evaluate its prevalence among patients with chronic hepatitis C (CHC), to correlate its presence to host and virological variables and to the response to combined therapy with interferon-alpha and ribavirin. CASUISTIC AND METHODS: 202 CHC naive patients (136 with chronic hepatitis and 66 with cirrhosis) were consecutively evaluated for the presence of cryoglobulins. Cryoprecipitates were characterized by immunoelectrophoresis and classified according to the Brouet's criteria. RESULTS: The prevalence of MC was 27% (54/202), and 24% of them (13/54) showed major clinical manifestation of the disease. Even though type III MC was more frequent (78%), symptomatic MC was more common in type II MC. The presence of cirrhosis (RR=2.073; IC95%=1.029-4.179; p=0.041), and age of the patients (RR=1.035; IC95%=1.008-1.062; p=0.01) were independently associated with the presence of cryoglobulins. No relationship was found with viral load and genotype. 102 patients were treated with interferon alpha and ribavirin. Among these, 31 had MC. Sustained virological response (around 30%) was similar in patients with and without MC (p=0.971). CONCLUSION: MC represents a prevalent complication in patients with CHC, specially older and cirrhotic patients. Only 24% of these patients show clinical manifestation of the disease, specially those with type II MC. The presence of MC did not affect the response to therapy.

Cryoglobulinemia in chronic hepatitis C: clinical aspects and response to treatment with interferon alpha and ribavirin

INTRODUCTION: The main extra-hepatic manifestation of hepatitis C is mixed cryoglobulinemia (MC). The aim of this study was to evaluate its prevalence among patients with chronic hepatitis C (CHC), to correlate its presence to host and virological variables and to the response to combined therapy with interferon-alpha and ribavirin. CASUISTIC AND METHODS: 202 CHC naive patients (136 with chronic hepatitis and 66 with cirrhosis) were consecutively evaluated for the presence of cryoglobulins. Cryoprecipitates were characterized by immunoelectrophoresis and classified according to the Brouet's criteria. RESULTS: The prevalence of MC was 27 percent (54/202), and 24 percent of them (13/54) showed major clinical manifestation of the disease. Even though type III MC was more frequent (78 percent), symptomatic MC was more common in type II MC. The presence of cirrhosis (RR = 2.073; IC95 percent = 1.029 - 4.179; p = 0.041), and age of the patients (RR = 1.035; IC95 percent = 1.008 - 1.062; p = 0.01) were independently associated with the presence of cryoglobulins. No relationship was found with viral load and genotype. 102 patients were treated with interferon alpha and ribavirin. Among these, 31 had MC. Sustained virological response (around 30 percent) was similar in patients with and without MC (p = 0.971). CONCLUSION: MC represents a prevalent complication in patients with CHC, specially older and cirrhotic patients. Only 24 percent of these patients show clinical manifestation of the disease, specially those with type II MC. The presence of MC did not affect the response to therapy.

INTRODUÇÃO: A crioglobulinemia mista (CM) representa importante complicação extra-hepática da hepatite C. Nesse estudo avaliamos sua prevelência em pacientes com hepatite C crônica (HCC) e relacionamos sua presença com aspectos clínicos e resposta ao tratamento com interferon alfa e ribavirina. CASUíSTICA E MÉTODOS: 202 pacientes consecutivos com HCC (136 com hepatite crônica e 66 com cirrose) foram avaliados para a presença de CM. Os crioprecipitados foram caracterizados por imunoeletroforese e classificados de acordo com BROUET et al. RESULTADOS: A prevalência de CM nessa população foi de 27 por cento (54/202), e, desses, 24 por cento (13/54) apresentaram manifestações clínicas maiores da doença. Embora MC tipo III tenha sido a forma mais freqüentemente encontrada, a doença sintomática foi mais comum entre os pacientes com MC tipo II. A presença de cirrose (RR = 2,073; IC95 por cento = 1,029 - 4,179; p = 0,041) e a idade do paciente (RR = 1,035; IC95 por cento = 1,008 - 1,062; p = 0,01) estiveram independentemente associadas à presença de CM. Não houve associação entre a presença de CM e genótipo ou carga viral do vírus C. No total, 102 pacientes foram tratados com interferon alfa e ribavirina. Desses, 31 apresentavam CM. A resposta virológica sustentada (em torno de 30 por cento) não diferiu entre pacientes com e sem CM (p = 0,971). CONCLUSÃO: CM é uma freqüente complicação na HCC, especialmente em pacientes com idade avançada e com cirrose hepática. Apenas 24 por cento desses pacientes apresentam manifestações clínicas da doença, sendo mais freqüentes entre portadores de CM tipo II. A presença de crioglobulinemia não afetou a resposta virológica ao tratamento com interferon alfa e ribavirina.

Anti-glomerular basement membrane glomerulonephritis in an HIV positive patient: case report.

We report on a case of a patient with HIV infection, diagnosed 18 months prior to the development of an anti-glomerular basement membrane (anti-GBM) rapidly progressive glomerulonephritis; this is probably the first report of such an association. A 30-year-old white man presented with elevation of serum creatinine (1.3 - 13.5 mg/dL within one month). At admission, the urinalysis showed proteinuria of 7.2 g/L and 8,000,000 erythrocytes/mL. Renal biopsy corresponded to a crescentic diffuse proliferative glomerulonephritis mediated by anti-GBM, and serum testing for anti-GBM antibodies was positive; antinuclear antibodies (ANA) and anti-neutrophilic cytoplasmic antibodies (ANCA) were also positive. The patient underwent hemodyalisis and was treated with plasmapheresis, cyclophosphamide and prednisone. The association described here is not casual, as crescentic glomerulonephritis is not common in HIV-positive patients, anti-GBM glomerulonephritis is rare and anti-GBM antibodies are frequently observed in HIV-positive subjects when compared to the overall population. Based on the current case and on the elevated frequency of the positivity for such antibodies in this group of patients, it is advisable to be aware of the eventual association between these two conditions and to promote an active search for anti-GBM antibodies and early diagnosis of eventual urinary abnormalities in HIV-positive subjects, considering the severity of anti-GBM glomerulonephritis.

Anti-glomerular basement membrane glomerulonephritis in an HIV positive patient: case report

We report on a case of a patient with HIV infection, diagnosed 18 months prior to the development of an anti-glomerular basement membrane (anti-GBM) rapidly progressive glomerulonephritis; this is probably the first report of such an association. A 30-year-old white man presented with elevation of serum creatinine (1.3 - 13.5 mg/dL within one month). At admission, the urinalysis showed proteinuria of 7.2 g/L and 8,000,000 erythrocytes/mL. Renal biopsy corresponded to a crescentic diffuse proliferative glomerulonephritis mediated by anti-GBM, and serum testing for anti-GBM antibodies was positive; antinuclear antibodies (ANA) and anti-neutrophilic cytoplasmic antibodies (ANCA) were also positive. The patient underwent hemodyalisis and was treated with plasmapheresis, cyclophosphamide and prednisone. The association described here is not casual, as crescentic glomerulonephritis is not common in HIV-positive patients, anti-GBM glomerulonephritis is rare and anti-GBM antibodies are frequently observed in HIV-positive subjects when compared to the overall population. Based on the current case and on the elevated frequency of the positivity for such antibodies in this group of patients, it is advisable to be aware of the eventual association between these two conditions and to promote an active search for anti-GBM antibodies and early diagnosis of eventual urinary abnormalities in HIV-positive subjects, considering the severity of anti-GBM glomerulonephritis.

Urinary neopterin quantification by reverse-phase high-performance liquid chromatography with ultraviolet detection.

Neopterin plays an important role in the malignant disease diagnostics. However, the methods employed in neopterin determination are generally difficult and/or time consuming. The aim of this work was to standardize a practical method to quantify neopterin using high-performance liquid chromatography-ultraviolet (HPLC-UV) and quantify it in patients with systemic lupus erythematosus (SLE). Urine was collected from healthy subjects (n= 49), patients with inactive (n= 15), active (n= 28), and highly active SLE (n= 6). The HPLC was performed using two coupled reverse-phase columns eluted with 150 mM sodium phosphate, pH 4.0, under a flow rate of 0.8 ml/min, with UV detector set at 353 nm and 100-fold diluted urines. The inter- and intra-assay studies presented an imprecision of 12.5% and 12.9% for quality controls of 3.94 and 1.1 micromol/ml, respectively. Recovery from 79.5% to 82% was observed throughout the assay's linear range. Subjects with active (874.2 +/- 165.38 micromol/mol creatinin) and highly active SLE (1753.8 +/- 453.9 micromol/mol creatinin) showed three- and sixfold increased neopterin levels, respectively, compared to subjects with inactive SLE (314.3 +/- 121.3 micromol/mol creatinin) and healthy subjects (294.6 +/- 178.6 micromol/mol creatinin) (P< 0.05). Briefly, the proposed method was precise, specific, and reproducible, not invasive and allows the urinary neopterin quantification only with UV detection.

Relato de caso: glomerulosclerose segmentar e focal familiar / Familial focal segmental glomerulosclerosis

A ocorrência familiar de glomeruloscierose segmentar e focal (GESF) vem sendo relatada na literatura e atualmente é a lesão histopatológica mais freqüente entre pacientes com síndrome nefrática familiar. Tanto a herança autossômica dominante quanto a herança autossômica recessiva já foram descritas. A doença caracteriza-se por pobre resposta ao tratamento com corticóide, evoluçãovariável para insuficiência renal crônica (IRC) e ausênciade recorrência no transplante renal. Os autores fazem uma revisão dos aspectos clínicos da GESF familiar e chamam a atenção para a importância deste diagnóstico. Vinte e nove membros de uma família brasileira (três gerações) com GESF familiar foram investigados e o estudo genético encontrou associação com o gene N PHS2 localizado no cromossomo 1 q25-3 1.

Valor da detecçäo de imunecomplexos circulantes na glomerulonefrite difusa aguda pós-estreptocócica / Value of detection of circulating immune complexes in acute poststreptococcal diffuse glomerulonephritis

Imunecomplexos circulantes (ICCs) foram pesquisados no soro de 60 pacientes com glomeruolonefrite difusa aguda pós-estreptocócia. Usando-se dois radioimunoensaios, níveis elevados de ICCs foram detectados em 18% e 36% dos pacintes pelos métodos do fator reumatóide monoclonal e da conglutinina, respectivamente. Níveis de ICCs näo se correlacionaram com níveis de uréia, proteinúria ou hipertensäo arterial. É provável que haja formaçäo de imunecomplexos in situ nos gomérulos. Outro mecanismo de ativaçäo e consumo de C3, independente da presença de ICCs, é sugerido

Acido siálico em glomerulonefrite difusa aguda pós-estreptocócica: um marcador válido? / Sialic acid in diffuse acute post-streptococcic glomerulonephritis: a valid marka?

Utilizando um método colorimétrico de dosagem de ácido siálico livre, que depende de sua reaçäo com o ácido tiobarbitúrico, estudamos 49 pacientes com GNDAPE, que foram comparados a 25 indivíduos normais. Quarenta e um por cento dos pacientes apresentavam valores elevados e significantemente maiores que os do grupo controle. A sensibilidade e especificidade do método foram respectivamente de 41% e 96%. Näo houve correlaçäo entre dosagem de ácido siálico livre e precocidade de nefrite clínica ou entre uréia plasmática e níveis de C3 séricos

Glomerulonefrite difusa aguda após-estreptocócica: fatos e controvérsias / Acute diffuse poststreptococcal glomerulonephritis: facts and controversies

Mecanismos imunológicos envolvidos na patogenia da glomerulonefrite difusa aguda pós-estreptocócica säo revistos neste artigo. Säo discutidos: a participaçäo dos imunecomplexos, seu local inicial de formaçäo (na circulaçäo ou in situ nos glomérulos), a natureza do sistema antígeno-anticorpo e a presença de fatores reumatóides nesses pacientes