Nieves Gallego

Impairment of Tubular Secretion of Urate in Renal Transplant Patients on Cyclosporine

The prevalence of hyperuricemia was investigated in 214 kidney allograft recipients, 81 were on azathioprine and steroids and 133 on cyclosprine (CyA) and low-dose steroids or on triple therapy. All had stable renal function, serum creatinine < 2.5 mg/dl, and a follow-up between 12 and 120 months. At the time of the study, blood and urine samples were obtained to perform tests of renal function. The renal handling of urate was evaluated by a combined pyrazinamide and probenecid test in 35 selected patients (12 normouricemic on azathioprine, 9 normouricemic on CyA and 14 hyperuricemic on CyA). The prevalence of hyperuricemia was higher in the group of patients on CyA (19.7 vs. 66.9%, p < 0.001), as well as the concentration of serum urate (6.1 +/- 1.9 vs. 7.6 +/- 1.7, p < 0.001), and serum creatinine (1.2 +/- 0.3 vs. 1.4 +/- 0.4, p < 0.001). In patients on CyA, multivariate analysis showed that the most important predictive variables of hyperuricemia were: serum creatinine, FEurate, diuretic use and CyA blood levels (r = 0.73, p < 0.0001). Thirteen patients on CyA (9.9%) had at least one episode of gouty arthritis. Those patients were older than the hyperuricemic patients without gout (45.7 +/- 6.7 vs. 37.1 +/- 13.5 years, p < 0.01), had worse renal function (serum creatinine 1.9 +/- 0.4 vs. 1.5 +/- 0.4 mg/dl, p < 0.01), and higher prevalence of hypertension (100 vs. 63.1%, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Prognosis of Children with Acute Renal Failure: A Study of 138 Cases

Acute renal failure (ARF) in children has a poor prognosis in spite of modern therapeutic techniques. For this reason, it would be useful to have prognostic indicators early in the course of the disease, in order to identify those patients that could benefit most from aggressive treatment. In an attempt to establish valid prognostic factors, we prospectively studied 138 cases of ARF in children. We examined age, sex, etiology of ARF, previous surgery, prerenal origin, clinical situation of the patient when first seen by the nephrologist and complications. All these variables were statistically analyzed individually by univariate tests and, except for sex and complications, also by multiple regression analysis. Median age of the patients was 26 months. The etiology of ARF was nephropathy in 16, tumor in 14, cardiopathy in 85 and other causes in 23 cases. For analysis, patients were divided into patients with and without prerenal ARF. In the prerenal group, mortality-related factors were hypotension, need for ventilatory support, age less than 1 month and serum values of creatinine. In the nonprerenal ARF group, the need for assisted ventilation and the need for dialysis correlate positively with the mortality, while an exclusive nephrological etiology was associated with less probability of death.

Nephrogenic diabetes insipidus and renal tubular acidosis secondary to foscarnet therapy.

Foscarnet is used as therapy of cytomegalovirus (CMV) infection in immunosuppressed subjects. We present a patient with human immunodeficiency virus infection under treatment with foscarnet for CMV retinitis who complained of thirst and polyuria. Laboratory data showed hypernatremia with increased plasma osmolality and metabolic hyperchloremic acidosis. A water deprivation test demonstrated a nephrogenic diabetes insipidus. Other laboratory studies, including urine pH, anion gap, titratable acidity, and bicarbonate, showed a distal tubular acidification defect. All abnormalities were transient, with recovery a few days after foscarnet withdrawal. No cases of renal acidosis, and only one case of nephrogenic diabetes insipidus, has been previously reported as a complication of foscarnet treatment. Our patient developed both nephrogenic diabetes insipidus and renal tubular acidosis with a temporal pattern that demonstrated a link between foscarnet therapy and these abnormalities.

Clinical Significance of IgM Mesangial Deposits in the Nephrotic Syndrome

We have studied 32 patients with idiopathic nephrotic syndrome aged from 3 to 59 years. The clinical course of 20 patients with IgM mesangial deposits was compared with that of 12 patients without glomerular immune deposits. The presence of IgM deposits seems to be unrelated to any particular clinical onset, histological pattern on light microscopy, therapy response, or clinical course in our relatively short follow-up. The conclusion from this study is that IgM mesangial deposition is not a marker for response to therapy in patients with idiopathic nephrotic syndrome.

Familial C1q Deficiency in 3 Siblings with Glomerulonephritis and Rothmund-Thomson Syndrome

Complete absence of C1q was demonstrated in the sera of 3 siblings in association with renal and cutaneous lesions. The serologic findings were consistent with an autoimmune disorder. Hematuria was the renal symptom present in all 3 patients; proteinuria was also present in 1. Renal biopsies showed mesangial proliferative glomerulonephritis with diffuse glomerular deposits of IgM and C3 in all cases. Clinical cutaneous manifestations and the histological picture were those of the Rothmund-Thompson syndrome. Three combined diseases, characterized by renal and cutaneous affection and serologic abnormalities, are presented in this paper.

Acute interstitial nephritis superimposed on glomerulonephritis: report of a case

A 7-year-old boy with a history of recurrent acute renal failure and macroscopic haematuria is reported. A renal biopsy performed during the first episode of renal function deterioration showed mesangial glomerulonephritis with C3 mesangial deposits. Macroscopic haematuria associated with respiratory infections recurred four times over the next 14 months, each time in association with acute derangement of renal function. A second biopsy showed acute interstitial nephritis and similar glomerular abnormalities. Retrospectively, a causal relationship between the ingestion of paracetamol and the appearance of the symptoms was observed. No derangement of renal function was present in subsequent episodes of macroscopic haematuria following removal of the offending drug. This is a case of drug-induced acute interstitial nephritis superimposed on a glomerular disease, and suggests the importance of recognizingthis association.

Progression of renal failure in chronic primary glomerular diseases.

The rate of progression of renal failure was analyzed in 19 patients with biopsy-proven chronic primary glomerular diseases, by the slope (regression coefficient) of the linear regression of reciprocal serum creatinine on time. The relative importance of proteinuria, sex, underlying disease and components of arterial pressure (systolic, diastolic and mean) was tested using stepwise multiple linear regression, the dependent variable being the slope of progression. We found that the only variable significantly related with slopes of progression was arterial pressure. Hypertension was found in 14 of the 19 patients. There was a significant linear relationship (p < 0.05) between mean arterial pressure and slopes of progression. Notwithstanding, the best fit to the data follows a quadratic function (p < 0.001 for mean arterial pressure), which corresponds to a negative parabolic curve. Therefore, either low or high values of mean arterial pressure were associated with faster mean progression rates. Thus, an accurate approach of this relationship fits a nonlinear regression model.

Carpal osteolysis: an unusual entity treated by renal transplantation.

Dra. Purificación Ros, C/Monforte de Lemos, 81, 7° A, E-28029 Madrid (Spain) Dear Sir, Carpal and tarsal osteolysis (CTO) is a severe disorder of unknown etiology characterized by gradual resorption and lysis of bones of the hands and feet, beginning in the carpal and tarsal bones [1]. The diagnosis is based on the X-ray abnormalities and both sporadic and familial cases have been reported [2,3]. The nephropathy appears more frequently in the sporadic form and it does not have specific features, appearing during childhood or adolescence, with progression to end-stage renal disease (ESRD) in a variable period of time [4–7]. We report here a case of a patient with sporadic CTO and renal failure that received a cadaveric renal transplant after treatment with continuous ambulatory peritoneal dialysis (CAPD). To our knowledge, there are only two previous cases successfully transplanted [8, 9]. Case Report A 14-year-old girl was admitted to the hospital to receive a renal transplant. Her previous medical history was unremarkable. At the age of 7 years, she consulted somewhere else because of slow growth, pes cavus and limitation of flexion and extension of both wrists. The physical examination at that time revealed height 107 cm (p < 3), weight 17.800 kg (p < 3). A rather distinctive and asymmetric face with micrognathia, retrognathia and hypertrichosis was evident. Small hands with ulnar deviation of the fingers and nodules at the level of proximal interphalangeal joints of the right hand were observed. Flexion and extension of both wrists were mildly limited. Routine laboratory data, including tests for renal function and urinalysis, were normal. X-rays of the wrists showed absence of the second line of the carpal bones with no other abnormalities. Karyotype was normal. Eight months before admission, she developed vomitting, generalized edema, dyspnea and oliguria and was admitted at another hospital. She looked severely ill and pale. Blood pressure was 160/96 mm Hg (p > 95). Heart rate was 140 bpm. Laboratory tests showed hemoglobin 80 g/l (8 g/dl), creatinine 1,096 μmol/l (12.4 mg/dl), urea Ill.7 mmol/l (313 mg/dl), sodium 135 mmol/l, calcium 1.57 mmol/l (6.3 mg/dl), total serum proteins 48 g/l. Serum phosphate was not reported. X-ray of the abdomen showed decreased-

Urinary Acidification Response to Furosemide Administration in Patients on Low-Dose Cyclosporine Therapy

The response of urinary acidification parameters and electrolytes to furosemide administration was prospectively studied in 9 psoriatic patients treated with a low-dose cyclosporine A schedule (initial dose: 5 mg/kg body weight) before beginning cyclosporine A, after 3 months on cyclosporine A and 1 month after cyclosporine A withdrawal. The test was also performed in 29 psoriatic patients after 3 months on 5 mg/kg body weight cyclosporine A treatment. There were no significant differences between before and after cyclosporine A treatment regarding furosemide-induced changes in urinary volume, sodium or potassium excretion. Contrarily, the post-furosemide urinary pH decrease and ammonium and titrable acid increase were significantly lower in cyclosporine-A-treated patients. Five of the 29 studied patients showed abnormal furosemide tests (17%). These patients had lower total serum CO2, urea and creatinine but similar serum potassium and fractional potassium excretion. We conclude that some patients treated with low-dose cyclosporine A therapy develop an abnormal tubular distal response to furosemide administration, suggesting an alteration in the H(+)-ATPase pump or a voltage-dependent mechanism.