Jose R. Salcedo

Focal glomerulosclerosis in children: correlation of histology with prognosis.

The clinical and pathologic data of 32 nephrotic children diagnosed as having focal glomerulosclerosis were retrospectively analyzed to determine what factors were responsible for progression to renal failure in 12 of these children. The patients were classified into three groups based on the histologic findings in their initial renal biopsies: Group I (n = 19) had a combination of global and segmental lesions; Group II (n = 8) had only globally sclerotic or obsolescent glomeruli; and Group III (n = 5) had only segmentally sclerosed glomeruli. Ten of the 12 patients with end-stage renal failure came from Group I and two from Group II. The median period from recognition of symptoms to renal failure was four years. Clinical features were of little prognostic value. However, comparison of the histopathologic data of the ten patients in Group I with renal failure (Group Ia) and Groups Ib, II, and III revealed that the risk of progressing to renal failure was significantly higher in patients having greater than 20% of their glomeruli involved by both global and segmental lesions (P = 0.005). Furthermore, patients in Group I and III had a lower probability of responding to treatment as compared to patients in Group II (P less than 0.025).

Vancomycin Prevents Polytetrafluoroethylene Graft Infections in Pediatric Patients Receiving Chronic Hemodialysis

Polytetrafluoroethylene (PTFE) grafts have been a useful addition to the pediatric hemodialysis vascular access armamentarium. In this study, 17 pediatric patients underwent 331 total months of hemodialysis via PTFE grafts. There was a statistically significant (P less than .025) decrease in the incidence of graft infections in 12 patients (235 patient-months) while receiving prophylactic parenteral vancomycin compared with 9 patients (96 patient-months) while receiving no vancomycin (0% v 44%). Vancomycin side effects were uncommon and mild. Vancomycin is a safe and effective agent for the prevention of PTFE graft infections in pediatric patients receiving chronic hemodialysis.

Urinothorax as a manifestation of nondilated obstructive uropathy following renal transplantation.

A 12-year-old patient developed prolonged nondilated urinary obstruction and pleural effusion shortly after undergoing renal transplantation. Renal sonography, angiography, and isotope renography failed to identify an obstructive process. On the 18th postoperative day, pleural effusion was noted in the right hemithorax, and by day 24, increased perinephric fluid was observed on renal scan. Following a nephrostomy, the pleural effusion resolved and renal function improved remarkably. A ureterovesical junction obstruction and renal pelvis tear that were later discovered were repaired. Whenever a ureteral obstruction is suspected the diagnosis should be pursued vigorously, despite normal radiologic findings, especially in the presence of pleural effusion. Consideration of the possibility of urinothorax in such cases may obviate the need for lung biopsy.

Accelerated recovery from immune-mediated thrombocytopenia with plasmapheresis

Autoimmune thrombocytopenia unresponsive to corticosteroid therapy developed in a 16-year-old female with long-standing Sjögrens syndrome. Serial plasma exchange caused a linear decrease in platelet antibody titer associated with a concomitant rise in platelet count. Statistical analysis of sequential platelet counts revealed an increase with plasmapheresis and immunosuppression that was significantly greater than that achieved with immunosuppression alone (p less than 0.005).

Hematuria after renal allograft biopsy: Treatment with aminocaproic acid

Aminocaproic acid (EACA) was used in 2 patients with cadaveric renal allografts because gross hematuria developed after percutaneous renal biopsies. Marked improvement was noted within twelve hours with no recurrence after discontinuation of EACA. EACA was effective in moderate renal failure.

Curable hypertension: Usefulness of renal vein renin ratio

A case of severe hypertension in an adolescent male is presented. Initial evaluation of hypertension revealed a unilateral nonfunctioning kidney with no lateralization of renal vein renin ratio. Following 10 months of medical therapy, lateralization of renal vein renin was demonstrated, with subsequent cure of hypertension following nephrectomy.

ATRIAL NATRIURETIC PEPTIDE (ANP): THE RELATIONSHIP WITH VOLUME, TACHYCARDIA AND CRITICAL ILLNESS

This study examines the effect of volume overload, atrial heart rate and critical illness on ANP levels in children. ANP levels were measured in 7 children undergoing dialysis(D), 4 children undergoing cardiac catheterization with electrophysiological pacing(EP), and 4 children in the ICU with pulmonary artery (PA) catheters. Thirty-four children were controls. The ANa results (RIA technique) are expressed in pg/ml (mean±SD). ANF levels in all 3 study groups were significantly different from normal (6.5±4.9) as follows: pre D pts, 139.7 ± 71.3 (p <.001); EP, 48.5^20.5 (p<.02); ICU patients, 104.0 ± 44.9 (p<.001). Pre and post D samples were significantly different (139.7±71.3 vs. 90.7±50.6, p<.004)and the change in ANF was correlated with the percent weight loss (R = .733). Pacing increased heart rates (117 ± 17 vs. 157 ± 20, p <.01) and ANP levels correlated with the increase in heart rate (48.5 ± 20.5 vs. 203.0 ± 66.0., p <.005, R = .66). ICU patients had elevated but statistically equivalent ANP levels in central venous, PA and arterial samples. CONCLUSION: ANP levels are increased in children with fluid overload, elevated heart rates and in critical illness. Removal of fluid from volume overloaded patients directly correlated with a decrease in ANP. Pacing of the right atrium in children caused a significant elevation of ANP confirming the association of tachycardia with ANP.

NON-INVASIVE INDICATORS OF RENAL ARTERY STENOSIS |[lpar]|RAS|[rpar]| IN CHILDREN

Unilateral and bilateral RAS are significant and potentially correctable causes of secondary hypertension in children. The technical difficulties and risks of angiography led us to do a retrospective analysis of non-invasive predictors of RAS in 10 consecutive hypertensive children who had renal arteriograms. Five had RAS and all had similar preliminary diagnostic evaluations. Patient ages ranged from 2 to 17 years and there were no differences in sex or age distribution between the RAS and non-RAS groups. An abnormal physical examination (abdominal bruit, cafe-au-lait spots) was highly related to RAS. Further, small sample predictive analysis indicated that a high accuracy of RAS classification may be possible utilizing only the variables of absolute elevations of plasma renin activity and BP [s/d 95%] (BP [s/d 95%] is the sum of the age-adjusted difference for systolic and diastolic BP exceeding the 95%). By contrast, poor correlation with the diagnosis of RAS was found with the following: renal scintillation scanning, depression in blood pressure (BP) using saralasin, and plasma aldosterone. We conclude that physical examination, plasma renin activity and BP [s/d 95%] are important predictors of RAS and help in the pre-selection of children needing renal angiography. In addition, the value of performing the other diagnostic tests studied is questioned.