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S A Mendoza

Publications and source records attributed to S A Mendoza.

At least 19 recordsLinked to original sources
PubMed1997

Treatment of the idiopathic nephrotic syndrome: regimens and outcomes in children and adults.

This review compares the biopsy patterns, complications, responses to therapy, and long-term outcomes of idiopathic NS in children and adults. On first examination, distinctions between the pediatric and adult diseases seem more quantitative than absolute. However, underlying determinants of outcome, including immunocompetence, growth, maturity, and senescence, can present very different challenges for pediatricians and internists. The major biopsy patterns in pediatric NS include MCD, FSGS, and DMP. MCD is overwhelmingly the most frequent and most steroid-responsive of the three but commonly presents problems of massive edema, serious bacterial infections, and multiple relapses. Because of the prompt response of pediatric MCD to corticosteroids, steroid resistance in children has generally been defined as persistence of proteinuria after 1 month of daily followed by 1 month of intermittent prednisone administration. By this criterion, nephrotic FSGS is usually steroid-resistant and, if not controlled by more aggressive therapy, typically progresses to ESRD. DMP is commonly steroid-resistant but may slowly resolve. It is not clear to what extent remissions of DMP represent a delayed response to steroids or would have occurred without treatment. Biopsies showing a few globally obsolescent glomeruli or mild mesangial hypercellularity may be associated with greater difficulty in management but have been included in the broad category of MCD. Moreover, evolution of patterns in serial biopsies, variable steroid-responsiveness of FSGS and DMP, and progression of some cases of MCD to ESRD suggest common features in the three major categories. Among adults with idiopathic NS, FSGS is the most frequent biopsy pattern, followed by MN (which is rare in children) and then by MCD. In contrast to its pediatric counterpart, MCD in adults is less regularly and more slowly responsive to corticosteroids and in the elderly is more commonly associated with hypertension and renal failure. MCD in adults is less likely to relapse once remission is achieved. Adults with FSGS present less commonly with severe edema than do children with this lesion. Although children and adults with FSGS present similar challenges of resistance to therapy and loss of renal function, the more aggressive oral steroid regimens used by internists preclude strict comparisons between pediatric and adult series. There is insufficient information to support a systematic analysis of DMP in adults. Cytotoxic agents and cyclosporine have been used with varying success in children and adults with difficult cases of NS. In MCD, an alkylating agent can increase the likelihood and duration of remission. Cyclosporine can also improve control in MCD, but continued treatment is often needed to maintain remission. Significant control of steroid-resistant FSGS has not been achieved with limited courses of an alkylating agent or cyclosporine. Longer courses of either of these immunosuppressants, especially when combined with intermittent steroid administration, can produce more complete and/or more sustained remissions. However, cyclosporine nephrotoxicity is more severe in FSGS than in MCD and in steroid-resistant than in steroid-dependent NS, regardless of biopsy pattern. A protocol combining iv M-P pulses, alternate-day prednisone, and an alkylating agent in steroid-resistant pediatric FSGS has produced the highest percentage of sustained remissions with normal renal function, of all reported regimens. Controlled trials of this and other combined drug protocols are needed in children and adults.

Adult↗
PubMed1996

Steroid-resistant nephrotic focal segmental glomerulosclerosis: a treatable disease.

If not aggressively treated, oral steroid-resistant (SRst) nephrotic focal segmental glomerulosclerosis (FSGS) is likely to progress to end-stage renal failure. Three observations challenge the conclusion of the International Study of Kidney Diseases in Children (ISKDC) that SRst FSGS is unresponsive to further immunosuppression: (1) The ISKDC definitions of response and relapse, which fit the patterns in minimal change disease, precluded appropriate recognition of partial or gradual responses. (2) In two ISKDC studies, a small number of children with FSGS in one case, and the use of a year of alternate-day prednisone as a control in the other, may have obscured the effects of cyclophosphamide. (3) Recent studies of more aggressive therapies have provided strong evidence of benefit. High-dose methylprednisolone infusion therapy, with alternate-day prednisone alone or with alternate-day prednisone plus an alkylating agent (the M-P/ triple therapy protocol) has achieved sustained, complete remissions with stable renal function in 66% of children with SRst FSGS, and near-complete resolution of proteinuria in another 9%. Cyclosporine (CsA) plus alternate-day prednisone has produced complete or near-complete remissions in 35% of similar cases. Whether or not controlled studies will confirm the apparently greater efficacy of the M-P/triple therapy protocol, the favorable outcomes with both the M-P and the CsA regimens support the conclusion that a conservative approach to SRst FSGS is no longer appropriate.

Child↗
PubMed1995

Pulmonary hemorrhage in children with glomerulonephritis.

Pulmonary hemorrhage may occur in patients with immune-mediated glomerulonephritis. This association can be seen in a variety of disorders including systemic lupus erythematosus, vasculitis, Wegener's granulomatosis, anaphylactoid purpura and Goodpasture's syndrome. Immune mechanisms, such as immune complexes and/or autoantibodies, play a role in the pathogenesis of pulmonary and glomerular injury. Acute pulmonary hemorrhage can lead to respiratory failure and has a high mortality. Therapy with immunosuppressive agents such as pulse methylprednisolone and cyclophosphamide will control the hemorrhage and improve pulmonary function in most cases.

Adolescent↗
PubMed1995

Extracorporeal membrane oxygenation in the neonate with congenital renal disease and pulmonary hypoplasia.

Extracorporeal membrane oxygenation (ECMO) is an effective treatment modality for the newborn with refractory hypoxemia. Oligohydramnios can be associated with congenital renal disease (CRD) and can result in respiratory insufficiency from pulmonary hypoplasia, delayed lung maturation, and persistent pulmonary hypertension of the newborn. In this retrospective study, the authors reviewed the outcome of four children with CRD who required ECMO in the neonatal period. Between October 1987 and December 1995, ECMO was used in four newborns with CRD and pulmonary hypoplasia unresponsive to maximal medical management. The causes of CRD were urinary obstruction (2), renal dysplasia (1), and vesicoureteral reflux (1). Neonatal survivors of ECMO with CRD had regular follow-up with a nephrologist, urologist, and pediatrician. Developmental history, assessment of renal function, and a nutritional evaluation were recorded on each visit. The follow-up period ranged from 6 months to 5 years. All patients with CRD were successfully weaned from ECMO. One child died, at 1 month of age, because of renal failure. The estimated glomerular filtration rates in the three survivors were 20, 24, and 60 mL/min/1.73 m2. Growth and development have been delayed in two patients. Based on the author's experience, ECMO may improve the survival of neonates with pulmonary hypoplasia and CRD. Factors associated with successful long-term outcome include (1) renal disease amenable to surgical correction, (2) aggressive nutritional support, and (3) a reliable social support system.

Abnormalities, Multiple↗
PubMed1995

Management of the difficult nephrotic patient.

Most children with nephrotic syndrome do well, usually with multiple relapses and remissions. Some children require high doses of oral steroids to sustain a remission and develop significant steroid toxicity. These patients frequently can be managed with oral alkylating agents or with cyclosporine. A few nephrotic children to not respond to oral prednisone. The most common biopsy finding in steroid-resistant patients is focal segmental glomerulosclerosis. Many patients with this condition progress to chronic renal failure. Evidence suggests that the outcome is improved with either cyclosporine or with a protocol using pulse intravenous methylprednisolone and oral alkylating agents.

Child↗
PubMed1995

Intravenous methylprednisolone and oral alkylating agent therapy of prednisone-resistant pediatric focal segmental glomerulosclerosis: a long-term follow-up.

UNLABELLED: Prednisone-resistant nephrotic syndrome (NS) due to focal segmental glomerulosclerosis (FSGS), the most common acquired disease requiring chronic dialysis and transplantation in children, has a low likelihood of response to alkylating agent therapy. This report summarizes the results of a 0.75-12.5 (average 6.33) year follow-up of 32 pediatric cases of prednisone-resistant FSGS treated with a regimen of high-dose intravenous methylprednisolone (M-P) and alternate-day prednisone, plus an alkylating agent in 25/32. On last followup: 21/32 were in remission [urine protein-to-creatinine ratios (Pru/Cru) < or = 0.2]; 3/32 had mild proteinuria (Pru/Cru > 0.2-0.5); 2/32 had moderate proteinuria (Pru/Cru > 0.5-1.9); and 6/32 remained nephrotic (Pru/Cru > or = 2.0). Of the incomplete or nonresponders; 3/11 progressed to end-stage renal failure; 5/11 had decreased creatinine clearances (CrCl): and 3/11 had persistent proteinuria with normal CrCl. All of the persistently nephrotic children, but none of the complete responders, developed decreased CrCl. All of the complete responders were able to stop treatment; four relapsed but responded well to retreatment. CONCLUSIONS: This regimen of methylprednisolone and alternate-day prednisone, with or without an alkylating agent, is effective in achieving sustained remissions and preserving normal renal function in the great majority of children with FSGS and prednisone-resistant NS.

Child, Preschool↗
PubMed1994

Pediatric renal transplantation in Laurence-Moon-Biedl syndrome.

Two cases of renal transplantation in pediatric patients with Laurence-Moon-Biedl syndrome are reported. Immunosuppressive therapy consisted of cyclosporine, prednisone and azathioprine. Renal function has been good but both patients developed morbid obesity.

Adolescent↗
PubMed1993

Evaluation of delayed puberty in the female adolescent with chronic renal failure.

The purpose of this report is to discuss the differential diagnosis of delayed puberty in the adolescent female with chronic renal failure. The appropriate therapy varies depending on the etiology of the delay. Frasier syndrome--chronic renal failure with true gonadal dysgenesis--should be considered in the diagnosis of a normal phenotypic female with end-stage renal disease and delayed puberty.

Adolescent↗
PubMed1992

End-stage renal disease and primary hypogonadism associated with a 46,XX karyotype.

OBJECTIVE: To determine the cause of absent sexual development in a 17-year-old girl with end-stage renal disease. DESIGN: Case study. PARTICIPANT: Seventeen-year-old girl with end-stage renal failure. INTERVENTIONS: None. MEASUREMENTS/MAIN RESULTS: The patient had phenotypically normal external female genitalia, müllerian duct hypoplasia, and no ovaries. Her serum gonadotropin levels were in the castrate range at baseline and after gonadotropin-releasing hormone stimulation. Her karyotype, in lymphocytes and cultured fibroblasts, was 46,XX. Analysis of genomic DNA, following polymerase chain reaction-amplication with oligonucleotide primers corresponding to the Y-encoded zinc finger protein ZFY and the testis-determining SRY gene, showed Y chromosome material in a male control but none in the patient. CONCLUSIONS: The results suggest a diagnosis of Frasier syndrome, a disorder characterized by true gonadal dysgenesis and end-stage renal disease occurring in normal phenotypic girls. Although previously reported only in individuals with a 46,XX karyotype, our studies indicate that Frasier syndrome may also occur in 46,XX girls. Delayed puberty is not uncommon in renal failure. This case illustrates the importance of measuring gonadotropin levels in teenage girls with delayed puberty and renal failure, particularly if the origin of the renal disease is obscure.

Adolescent↗
PubMed1992

Treatment of childhood nephrotic syndrome.

This review examines selected aspects of the treatment of the nephrotic syndrome in children. Particular attention has been paid to two groups of nephrotic children. First, children with steroid-responsive nephrotic syndrome are discussed. Recently, a series of controlled studies have provided important information regarding the optimal duration of steroid therapy. Initial episodes of the nephrotic syndrome are best treated with "long" courses of prednisone therapy (6 wk of high-dose daily prednisone followed by 6 wk of alternate-day prednisone). In contrast, relapses do as well with "short" courses (about 2 wk of daily prednisone and 2 wk of alternate-day therapy). Some children who are steroid responsive require high doses of prednisone to remain in remission. These patients may require alkylating agent therapy. The most common cause of steroid-resistant nephrotic syndrome is focal segmental glomerulosclerosis. Over the past 10 yr, these patients have been treated with an intensive protocol involving multiple infusions of high-dose methylprednisolone and, in many cases, oral alkylating agent therapy. Current experience with this treatment is presented. The protocol appears to improve the outcome in children with focal segmental glomerulosclerosis, although it is believed that it is essential that these observations be confirmed by a controlled trial. There is also interest in the use of angiotensin-converting enzyme inhibitors and cyclosporine in the treatment of childhood nephrotic syndrome. The experience with these agents is briefly reviewed, but the current data are inadequate to indicate their role(s) in this condition.

Administration, Oral↗
PubMed1991

Symptomatic cholelithiasis in pediatric renal transplant recipients.

We report two cases of symptomatic cholelithiasis in pediatric renal transplant recipients immunosuppressed with cyclosporine (CsA), prednisone and azathioprine. CsA was present in the bile and in the cholesterol gallstones of one patient. The diagnosis of cholelithiasis was established in both cases by abdominal ultrasound examination.

Child↗
PubMed1991

Peritoneal dialysis for acute renal failure in children.

Fifty infants and children with acute renal failure were treated with acute peritoneal dialysis between 1987 and 1990. The patients were dialyzed using either a catheter introduced percutaneously over a guide-wire (n = 40) or a Tenckhoff catheter (n = 10). The cause of the acute renal failure was primary renal disease in 17 children, cardiac disease in 19, and trauma/sepsis in 14. Peritoneal dialysis succeeded in controlling metabolic abnormalities, improving fluid balance, and relieving the complications of uremia. The procedure had few major complications. Overall mortality was 50%, reflecting the serious nature of the underlying diseases. We conclude that acute peritoneal dialysis is a safe and effective treatment in most pediatric patients with acute renal failure. Our series of patients treated with acute peritoneal dialysis serves as a basis of comparison for the evaluation of new modalities of therapy in childhood acute renal failure.

Acute Kidney Injury↗