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M J Kemper

Publications and source records attributed to M J Kemper.

At least 19 recordsLinked to original sources
PubMed2000

Unfavorable response to cyclophosphamide in steroid-dependent nephrotic syndrome.

Development of steroid dependency represents a significant therapeutic challenge in steroid-sensitive nephrotic syndrome. Previous studies have shown conflicting results concerning the benefit of a 12-week treatment with cyclophosphamide (CPO), with 24%-67% of patients achieving long-term remission. We therefore analyzed the clinical response of 20 consecutive children with steroid-dependent nephrotic syndrome (SDNS) (12 male, median age at start of treatment 5.9 years, range 3.2-14.7 years) treated at our institution with CPO (2 mg/kg per day) for 12 weeks since 1989. Median duration of follow-up was 5.8 (range 1.1-9.25) years. Only 6 of 20 children (30%) showed a long-term remission of >2 years, while 14 of 20 (70%) developed relapses again. Of these, 12 patients (86%) again developed steroid dependency, requiring further alternative treatment. Our data show that a 12-week course of CPO leads to unfavorable results in the majority of patients with SDNS. We therefore conclude that there is a need for further optimization of therapy in SDNS.

Child↗
PubMed2000

Long-term results of pre-emptive liver transplantation in primary hyperoxaluria type 1.

In primary hyperoxaluria type 1 (PH 1), deficiency or mistargeting of hepatic alanine glyoxylate aminotransferase (AGT) results in over-production of oxalate and hyperoxaluria, leading to nephrocalcinosis and development of end-stage renal disease (ESRD) in the majority of patients. Renal transplantation (Tx) alone carries a high risk of disease recurrence as the metabolic defect is not cured. Therefore, combined liver/kidney Tx is recommended for patients with ESRD. An alternative approach is to cure PH 1 by pre-emptive isolated liver Tx (PLTx) before ESRD has occurred, but this approach has been carried out only occasionally and there are no uniformly accepted recommendations concerning the timing of this procedure. We report follow-up 3-5.7 yr after performing successful PLTx in four children (at the age of 3-9 yrs) with PH 1 prior to the occurrence of ESRD (glomerular filtration rate [GFR] range 27-98 mL/min/1.73 m2). There was no mortality or long-term morbidity associated with the Tx procedure. Plasma and urinary oxalate levels normalized rapidly within 4 weeks, and renal function did not deteriorate under immunosuppression, even in one patient with advanced chronic renal failure (GFR 27 mL/min/1.73 m2) who showed a stable course for more than 5.7 yrs. Although treatment must be individualized in this severe metabolic disorder, and PLTx has to be regarded as an invasive procedure, we consider that PLTx should be offered and considered early in the course of PH 1. PLTx cures the metabolic defect in PH 1 and can help to prevent, or at least delay, the progression to ESRD and systemic oxalosis.

Acute Kidney Injury↗
PubMed1999

Plasma calcium oxalate supersaturation in children with primary hyperoxaluria and end-stage renal failure.

BACKGROUND: Children with primary hyperoxaluria type 1 (PH 1) are at great risk to develop systemic oxalosis in end-stage renal disease (ESRD), as endogenous oxalate production exceeds oxalate removal by dialytic therapy. As oxalate accumulates, calcium oxalate (CaOx) tissue deposition occurs. Children with other causes of ESRD, however, are not prone to CaOx deposition despite elevated plasma oxalate (POx) levels. METHODS: Our study objective was to examine the potential mechanisms for these observations. We measured POx, sulfate, citrate, and calculated CaOx saturation (betaCaOx) in 7 children with ESRD caused by PH 1 and in 33 children with non-PH-related ESRD. Maintenance hemodialysis (HD) was performed in 6 PH 1 and 22 non-PH patients: Pre- and post-HD levels were analyzed at this point and were repeated twice within 12 months in 5 PH 1 and 14 non-PH patients. Samples were obtained only once in 12 patients (one PH 1) on peritoneal dialysis (PD). After liver-kidney or kidney transplantation, plasma levels were measured repetitively. RESULTS: The mean POx was higher in PH 1 (125.7 +/- 17.9 micromol/liter) than in non-PH patients (44.2 +/- 3.3 micromol/liter, P < 10(-4)). All other determined anions did not differ between the two groups. betaCaOx was higher in PH 1 (4.71 +/- 0.69 relative units) compared with non-PH children (1.56 +/- 0.12 units, P < 10(-4)). POx and betaCaOx were correlated in both the PH 1 (r = 0.98, P < 2 x 10(-4)) and the non-PH group (r = 0.98, P < 10(-4)). POx and betaCaOx remained stable over time in the non-PH children, whereas an insignificant decline was observed in PH 1 patients after six months of more aggressive dialysis. betaCaOx was supersaturated (more than 1) in all PH 1 and in 25 out of 33 non-PH patients. Post-HD betaCaOx remained more than 1 in all PH 1, but in only 2 out of 22 non-PH patients. In non-PH children, POx and betaCaOx decreased to normal within three weeks after successful kidney transplantation, whereas the levels still remained elevated seven months after combined liver-kidney transplantation in two PH 1 patients. CONCLUSION: Systemic oxalosis in PH 1 children with ESRD is due to higher POx and betaCaOx levels. As betaCaOx remained supersaturated in PH 1 even after aggressive HD, oxalate accumulation increases, and CaOx tissue deposition occurs. Therefore, sufficient reduction of POx and betaCaOx is crucial in PH 1 and might only be achieved by early, preemptive, combined liver-kidney transplantation or liver transplantation alone.

Bone and Bones↗
PubMed1999

Iron homeostasis in relapsing steroid-sensitive nephrotic syndrome of childhood.

AIM: Urinary transferrin loss is a typical feature in relapse of the idiopathic nephrotic syndrome, however, the impact on serum iron homeostasis and hematological parameters has not been studied systematically so far. PATIENTS AND METHODS: Therefore, we investigated serum iron (Fe), erythropoietin (EPO), ferritin (FN), transferrin (TF), total iron-binding capacity (TEBK), transferrin saturation and the soluble transferrin receptor (sTFR) combined with hematological parameters (hemoglobin, MCV, MCH) in 42 children with relapsing, steroid-sensitive nephrotic syndrome (NS) in remission (RM, n = 26) and relapse (RL, n = 16), including 13 patients who were studied in both states. Thirty-three age-matched healthy children served as controls. RESULTS: Fe, TEBK and TF were significantly reduced in RL compared to RM in cross-sectional as well as in paired studies while ferritin, hematological parameters and EPO levels remained unchanged. A significant increase, however, of the soluble transferrin-receptor could be demonstrated in cross-sectional analysis comparing RL to RM and healthy controls (3568+/-713 mg/ml vs 2625+/-576 vs 2646+/-697; p < 0.001 respectively) as well as in paired analysis of 13 patients in RL and RM (p < 0.001). CONCLUSION: We conclude that transient transferrin and iron deficiency occurs in RL of INS but this seems to be counterbalanced by upregulation of the sTFR, a mechanism that might be important in preventing the development of iron deficiency anemia during the active nephrotic state.

Adolescent↗
PubMed1998

[The treatment with levamisole of frequently recurring steroid-sensitive idiopathic nephrotic syndrome in children].

BACKGROUND AND OBJECTIVE: The treatment of frequently relapsing steroid-sensitive nephrotic syndrome in children with established immunosuppressive drugs (steroids, cyclophosphamide, cyclosporin A) sometimes presents problems because of the expected incidence of side effects. Stimulation of the immune system with the anthelminthic drug levamisole in this disease has been documented. Aim of this study was to assess in a prospective but uncontrolled series of observations its value and side effects. PATIENTS AND METHODS: 25 patients (15 boys, ten girls; median age 10 [3.5-22] years) were given levamisole, 2 mg/kg/48 h. Before this treatment was started eight of the children/adolescents (32%) had frequent relapses and 17 (68%) had become steroid-dependent. Treatment was started during steroid-induced remission and continued for 3-24 (median 6) month, while steroids were discontinued after four weeks. RESULTS: Relapse frequency per patient month was reduced from a mean of 0.5 (0.33-0.83) before to 0.31 (0-0.67) during levamisole administration (P < 0.001). In 12 patients (48%) no or considerably fewer relapses were observed. Patients with exclusively frequent relapses responded to levamisole better than those with steroid dependence (7/8 [87.5%] vs. 5/18 [27.7%], P = 0.01). Side effects were reversible leukopenia in two patients and nonspecific skin rash as well as epigastric pain in one patient. CONCLUSION: Levamisole is an efficacious addition or alternative, with a low incidence of side effects, in the treatment of frequently relapsing nephrotic syndrome, particularly so in yet steroid-dependent patients.

Adjuvants, Immunologic↗
PubMed1998

Plasma calcium-oxalate saturation in children with renal insufficiency and in children with primary hyperoxaluria.

BACKGROUND: Calcium-oxalate (CaOx) deposition and systemic oxalosis are uncommon in children with chronic renal failure (CRI), but frequent in children with primary hyperoxaluria type I (PH-1). We hypothesized a difference in plasma CaOx saturation (betaCaOx) and its determining factors would explain this discrepancy. METHODS: Therefore, in addition to common biochemical measurements, plasma-oxalate (POx), citrate (PCit) and sulfate (PSulf) (plasma anions) were measured and betaCaOx was calculated in 17 PH-1 patients with normal renal function receiving pyridoxine and citrate therapy, in 54 children with CRI (SCr 0.9 to 5.9 mg/dl), and in 50 healthy children (NL). Plasma anions were analyzed by ion-chromatography and betaCaOx was calculated using a PC-based program for solution equilibria. RESULTS: Compared to NL, all plasma anion levels and betaCaOx were higher in PH-1 and CRI; POx, PCit and betaCaOx were higher in PH-1 than in CRI (P < 0.05), but PSulf was higher in CRI (P < 0.01). BetaCaOx and POx were correlated in all groups (r = 0.63 to 0.95, P < 10(-4)). POx and betaCaOx were both inversely correlated to a decrease in GFR in CRI patients. PCit and PSulf did not influence betaCaOx. Although supersaturation (betaCaOx > 1) was found in 7 CRI and in 4 PH-1 patients, eye examinations were suspicious for CaOx depositions only in the PH-1 patients, while systemic oxalosis was confirmed in one PH patient because of oxalate osteopathy. CONCLUSIONS: In PH-1, POx and betaCaOx are elevated even with normal renal function, which increases the likelihood of CaOx crystal deposition. Therefore, more effective therapy to decrease betaCaOx is crucial to reduce the risk of systemic oxalosis. In children with CRI unknown, but presumably protective substances, help prevent the risk of systemic oxalosis, despite increased POx and betaCaOx levels, often to supersaturation levels.

Calcium Oxalate↗
PubMed1998

Simultaneous determination of oxalate, citrate and sulfate in children's plasma with ion chromatography.

To improve our understanding of both diagnosis and treatment of diseases of oxalate metabolism, we first set out to establish a new ion-chromatographic method to determine normal plasma levels of oxalate, citrate and sulfate from single plasma samples. In 50 infants and children (23 girls, 27 boys, aged 0.2 to 17 years) with normal renal function, blood was drawn in Li-heparin tubes, placed on ice and preserved immediately with 40 microliters M HCl/ml plasma in two ultracentrifugation steps. For measurement, plasma was injected onto an ion chromatography system with NaOH as the mobile phase, and then run as a linear gradient from 5 mM to 52.5 mM over 21 minutes. Analysis yielded measurable and reproducible oxalate (6.43 +/- 1.06 microM/liter), citrate (79.3 +/- 27.4 microM/liter) and sulfate (235.0 +/- 85.3 microM/liter) levels, without any age and gender specific differences. The least detectable plasma oxalate level was < 0.3 microM with a high reliability and reproducibility (coefficient of variance 1.95 to 4.75%). In conclusion, we established a reproducible, precise method to determine the relevant plasma anions involved in mineral metabolism, which heretofore have not been easily measurable. Studies of diseases of oxalate and citrate metabolism are ongoing on the basis of the normal plasma values achieved in this study.

Adolescent↗
PubMed1997

Primary hyperoxaluria type 2.

UNLABELLED: Primary hyperoxaluria type 2 (PH2) is a rare disease with only 24 patients reported in the literature so far. It should be considered in any patient presenting with urolithiasis or nephrocalcinosis due to hyperoxaluria. The metabolic defect is deficiency of D-glycerate dehydrogenase/glyoxylate reductase leading to characteristic hyperoxaluria and excretion of L-glycerate, the cornerstone of diagnosis of PH 2. Although development of terminal renal failure seems to be less prevalent than in PH 1, recent reports indicate that chronic as well as terminal renal insufficiency may occur. Therefore specific therapeutic measures should aim at reduction of urinary calcium oxalate saturation by potassium citrate or pyrophosphate to reduce the incidence of nephrolithiasis and nephrocalcinosis and thus improve renal survival. Secondary complications (obstruction, urinary tract infections and pyelonephritis) must be avoided. In patients with terminal renal failure isolated renal transplantation seems to carry a high risk of disease recurrence. CONCLUSION: PH 2 is a rare but important cause of urolithiasis and nephrocalcinosis; long-term follow up is necessary, since the renal prognosis may be worse than previously anticipated.

Humans↗
PubMed1997

IgG2 deficiency in uremic children is not restricted to peritoneal dialysis treatment.

To date there are no data concerning IgG subclasses in children with preterminal chronic renal failure (CRF), although a reduction of total serum IgG, including its major subclasses IgG1 and IgG2, has been demonstrated in patients on peritoneal dialysis (PD). Therefore we studied total IgG, IgA, IgM, and IgG subclasses in preterminal CRF (n = 25), PD (n = 22) patients, and 13 age-matched healthy children and also compared results with age-related normal values previously established in 226 healthy children. While total IgG, IgA, IgM, and IgG 1 were comparable, there was a significant deficiency of IgG2 in children both with preterminal CRF and on PD compared with controls. Moreover, the prevalence of IgG2 deficiency compared with age-related normal values was significantly increased not only in PD but also in preterminal CRF patients. We conclude that there are alterations in serum IgG subclasses in children with CRF, with IgG2 deficiency not restricted to PD, but being present in the preterminal state as well.

Adolescent↗
PubMed1997

Novel COL4A5/COL4A6 deletions and further characterization of the diffuse leiomyomatosis-Alport syndrome (DL-AS) locus define the DL critical region.

Diffuse leiomyomatosis (DL) with Alport syndrome (AS) has been shown to be associated with contiguous gene deletions of the COL4A5 and COL4A6 genes, with the COL4A6 breakpoint of the deletions invariably located in the large intron 2 of the gene. We describe four YAC clones covering the locus and a refined restriction map of the entire COL4A6 gene. These resources have allowed us to make a precise estimate of the size of COL4A6 introns 2 and 3, as well as the size of the gene itself. We also describe five novel deletions which, in conjunction with previous reports, allow the definition of a 90-kb critical region in which to search for a gene or other entity involved in the pathogenesis of DL.

Adult↗
PubMed1997

Disseminated islands of gastric mucosa in jejunum and ileum detected by technetium-99m-pertechnetate scintigraphy.

Disseminated islands of gastric mucosa are very rare in the small intestine. The secretion of hydrochloric acid can lead to ulceration which results in gastrointestinal bleeding. It is often difficult to localize the focus in case of gastrointestinal blood loss especially in the small bowel. Technetium-99m-pertechnetate scintigraphy may be a helpful tool in detecting ectopic gastric mucosa. We report a case of a 21-mo-old boy with recurrent gastrointestinal bleeding. By using pertechnetate scintigraphy, extensive tracer accumulation in the jejunum and proximal ileum was detected. Histologically, multiple islands of ectopic gastric mucosa were found in about 50 excited mucosal and transmural biopsies. The unusual finding of disseminated accumulation of 99mTc-pertechnetate in the small intestine was the diagnostic clue for such a rare disease.

Biopsy↗
PubMed1996

Effective treatment of acute hyperkalaemia in childhood by short-term infusion of salbutamol.

UNLABELLED: Hyperkalaemia is a life-threatening emergency and infusion of glucose with insulin has so far been regarded as the standard treatment of choice. Recently the beta-2 stimulatory drug salbutamol has been shown to be an effective agent to treat hyperkalaemia by inducing a shift of potassium into the intracellular compartment. We treated 15 children aged 0.1-14 (mean 5.2) years suffering from acute hyperkalaemia (mean level 6.6 +/- 0.54, range 5.9-7.7 mmol/l) with a single infusion of salbutamol (5 micrograms/kg over 15 min). Serum potassium concentrations decreased significantly within 30 min to levels of 5.74 +/- 0.53 and 4.92 +/- 0.53 mmol/l after 120 min (P < 0.001, respectively). No side-effects occurred other than a light increase in heart rate in 3 patients. CONCLUSION: A single intravenous infusion of salbutamol at a dose of 5 micrograms/kg is a highly effective treatment for hyperkalaemia with minimal clinical side-effects. The effect lasts for at least 120 min and may reverse hyperkalaemia in some patients without further interventions so that salbutamol seems justified as the first choice treatment for this condition in childhood.

Adolescent↗
PubMed1996

Nephrocalcinosis in a patient with primary hyperoxaluria type 2.

Although nephrocalcinosis is a classical finding in primary hyperoxaluria type 1 (PH 1) associated with a poor renal survival it is exceptional in patients with PH type 2 (PH 2), characterized by a more favorable outcome. We describe an 8-month-old girl who suffered from recurrent urinary tract infections. Imaging studies revealed a profound corticomedullary nephrocalcinosis with no evidence of calculi. Urinary oxalate and D-glycerate excretion were massively elevated, while urinary glycolate or glyoxylate could not be detected, confirming the diagnosis of PH 2. Although the nephrocalcinosis progressed radiologically, renal function remained stable for over 2 years. Only further follow-up will show whether the associated nephrocalcinosis worsens the prognosis of our patient and of PH 2 in general.

Child↗
PubMed1996

Hyperkalemia: therapeutic options in acute and chronic renal failure.

Hyperkalemia is a life threatening emergency and warrants immediate treatment because of its deleterious cardiac consequences. Initial measures in mild cases include restriction and binding of dietary potassium, correction of metabolic acidosis and increasing urinary excretion by furosemide. In moderate and severe hyperkalemia infusion of glucose with insulin has been regarded as the standard medical treatment so far. However, recently also the beta 2 stimulatory drug salbutamol has been shown to be an effective agent to treat hyperkalemia by inducing a shift of potassium into the intracellular compartment. We treated 15 pediatric patients of different age groups (mean age 5.16, range 0.1-16 years) suffering from acute hyperkalemia (mean level 6.6, range 5.9-7.7 mmol/l) by means of a single infusion of salbutamol (5 micrograms/kg over 15 minutes). Serum potassium concentrations decreased significantly to 5.74 +/- 0.53 after 30 minutes and furthermore to 5.19 +/- 0.48 and to 4.92 +/- 0.53 mmol/l after 60 and 120 minutes, respectively (p < 0.001 at all stages compared to pre-treatment). Since no side effects occurred besides a slight increase of heart rate in 3 patients, we conclude that short-term intravenous salbutamol infusion is an effective, rapid, safe and predictable way to treat children of any age suffering from acute hyperkalemia and therefore has become the first line treatment in our center.

Acute Disease↗
PubMed1975

Adam Politzer, otology and the Centennial Exhibition of 1876.

The Centennial Exhibition of 1876 was held in Philadelphia. Among the exhibits was a collection of temporal bone dissections produced by Adam Politzer of Vienna. This exhibit included both normal and pathological temporal bones, and emphasized the relationship of the tympanic membrane to the middle ear, external canal and bony labyrinth. At the close of the Centennial Exhibition the collection was purchased by the College of Physicians of Philadelphia. This collection and the congress associated with the Centennial had a tangible effect on the otology in this country.

Ear Canal↗
PubMedDate not supplied

[Bilharziasis as the etiology in hematuria and proteinuria in childhood].

Haematuria and proteinuria are important symptoms of primary and secondary nephropathies. We report three african children presenting to our center in whom infection with S. haematobium resulted in haematuria and proteinuria. The third patient concomitantly suffered from steroid-sensitive relapsing nephrotic syndrome with the histological features of focal and segmental glomerulo-sclerosis. The diagnosis was in all cases established by light microscopy and urinary symptoms improved after treatment with praziquantel. In the third patients long term remission of the nephrotic syndrome could be maintained after 4 doses of praziquantel for recurrent bladder symptoms. We conclude that bilharziosis must be considered in the differential diagnosis of children with haeamturia and proteinuria even in Europe. The diagnosis can be established easily by light microscopy and an effective and low-risk treatment (with Praziquantel) can be offered.

Adolescent↗