RESUMO
OBJECTIVE: To describe the clinical and laboratory features of obesity associated proteinuria and focal segmental glomerulosclerosis. STUDY DESIGN: The patients were seen over a 12-year period at two large children's hospitals. Renal biopsies, performed for the diagnosis of unexplained heavy proteinuria and prepared for light, immunofluorescent, and electron microscopy, were read independently by two pediatric pathologists. Blood pressure, body mass index, serum levels of creatinine, albumin, and cholesterol, and 24-hour urinary protein were measured. RESULTS: Seven African American adolescents were identified with obesity-associated proteinuria, which was characterized by severe obesity (120 +/- 30 kg), markedly elevated body mass index (46 +/- 11), mild hypertension (134/74 +/- 10/18 mm Hg), slightly low to normal serum albumin levels (3.6 +/- 0.2 g/dL), moderately elevated serum cholesterol levels (196 +/- 60 mg/dL), and elevated 24-hour protein excretion (3.1 +/- 1.3 g/dL). Calculated creatinine clearance was normal in 6 patients and decreased in one. Typical renal histologic features included glomerular hypertrophy, focal segmental glomerulosclerosis, increased mesangial matrix and cellularity, relative preservation of foot process morphology, and absence of evidence of inflammatory or immune-mediated pathogenesis. One patient showed a dramatic reduction in proteinuria in response to weight reduction. Three patients who were given angiotensin-converting enzyme inhibitors had reduced urinary protein losses from 2.9 g to 0.7 g per day. One patient developed end-stage renal disease. CONCLUSION: Obese adolescents should be monitored for proteinuria, which has distinct clinical and pathologic features and may be associated with significant renal sequelae. Such proteinuria may respond to weight reduction and/or treatment with angiotensin-converting enzyme inhibitors.
Assuntos
Glomerulosclerose Segmentar e Focal/etiologia , Obesidade Mórbida/complicações , Proteinúria/etiologia , Adolescente , População Negra , Índice de Massa Corporal , Peso Corporal , Criança , Feminino , Glomerulosclerose Segmentar e Focal/etnologia , Glomerulosclerose Segmentar e Focal/patologia , Humanos , Rim/patologia , Masculino , Obesidade Mórbida/etnologia , Obesidade Mórbida/patologia , Prognóstico , Proteinúria/etnologia , Proteinúria/patologia , Índice de Gravidade de DoençaRESUMO
Renal stones containing calcium can occur in patients with type 1 glycogen storage disease. We studied 11 patients with glycogen storage disease. Five patients had renal calculi, nephrocalcinosis, or both, and five had hypercalciuria. Serum levels of calcium, phosphorus, parathyroid hormone, and urate were normal. Serum levels of 1,25-dihydroxyvitamin D were elevated in each patient. None of the patients had a metabolic acidosis, but all nine who were tested had evidence of impaired acid excretion. In response to an acid load, eight of the nine patients had subnormal titratable acid excretion, and nine had subnormal ammonia excretion; six of nine patients were unable to secrete hydrogen ions in response to bicarbonate administration. These data indicate that patients with type 1 glycogen storage disease have an incomplete form of distal renal tubular acidosis. This may be the cause of hypercalciuria and nephrocalcinosis in these patients.
Assuntos
Acidose Tubular Renal/etiologia , Doença de Depósito de Glicogênio Tipo I/complicações , Cálculos Renais/etiologia , Adulto , Cálcio/análise , Criança , Pré-Escolar , Citratos/urina , Feminino , Doença de Depósito de Glicogênio Tipo I/sangue , Doença de Depósito de Glicogênio Tipo I/urina , Humanos , Cálculos Renais/química , Masculino , Nefrocalcinose/etiologia , Vitamina D/sangueRESUMO
The renal tubular Fanconi syndrome developed in five patients with Wilms tumor after treatment with ifosfamide, a derivative of cyclophosphamide. Glomerular filtration rates were severely decreased. Renal function was investigated because of the development of rickets. All patients had undergone reduction of renal mass by nephrectomy. None had preexisting renal tubular injury. The syndrome developed at cumulative doses of ifosfamide of 39 to 99 gm/m2. Low serum bicarbonate and phosphate concentrations with glucosuria, aminoaciduria, and hypochloremic metabolic acidosis were the manifestations of the Fanconi syndrome. Bicarbonate and phosphate replacement resulted in bone healing, but recovery of tubular and glomerular function did not occur. Monitoring of these laboratory values during ifosfamide therapy could allow earlier replacement therapy to prevent severe bone disease.