Biomedical subjects

D Michalk

Publications and source records attributed to D Michalk.

At least 19 recordsLinked to original sources

PubMed2002

Type I IgE receptor, interleukin 4 receptor and interleukin 13 polymorphisms in children with nephrotic syndrome.

Polymorphisms in the genes encoding the high-affinity IgE receptor, the interleukin 4 (IL4) receptor and IL13 can be associated with the development of asthma and allergy. Although several studies have described an association between atopy and idiopathic childhood nephrotic syndrome (NS), it is not clear whether this association is of a causal nature. Furthermore, it is not known whether these polymorphisms are associated with the clinical course of NS. A total of 84 children (52 male and 32 female; mean age 12.1 years) with NS were included in the present study. Of these, 78 could be classified as either atopic or non-atopic. Atopy was defined by elevated IgE levels (>100 k-units/l) and/or a positive history of atopy (33 of 78 patients). DNA was extracted from blood collected in EDTA tubes, and polymorphisms at positions 50 and 551 of the IL4 receptor, position 110 of IL13 and position 181 of the high-affinity IgE receptor were investigated by sequence-specific PCR or direct sequencing. Although we noted a strong tendency towards a higher allele frequency of polymorphisms in children with atopy and NS compared with children with NS but without atopy (IL4 50, 30% compared with 18%; IL4 551, 39% compared with 31%; IL13 110, 45% compared with 33%; IgE 181, 12% compared with 13%), these differences did not reach statistical significance. There were no differences in the frequency of polymorphisms between the different clinical courses of NS (frequent relapsers, steroid-dependent or steroid-resistant NS). We conclude that polymorphisms in the IL4 receptor, the high-affinity IgE receptor and IL13 do not seem to predict the clinical course of NS, despite the fact that serum IgE elevations are more frequent in patients with NS than in normal control subjects. The investigated polymorphisms may contribute to the IgE switch in patients with NS.

Adolescent↗

PubMed2001

Congenital cystic adenomatoid malformation type 4.

A 9-day-old boy presented in respiratory distress and with failure to thrive. The chest X-ray showed a hyperlucent area of the left lung. A resection of the markedly emphysematous segment 2 of the left upper lobe was performed assuming the emphysematous tissue was due to congenital lobar emphysema (CLE). Histological examination of the lung tissue, however, revealed a pattern consistent with congenital cystic adenomatoid malformation (CCAM) type 4. The therapy for CLE as well as for CCAM is similar, i.e., resection of the emphysematous tissue. As far as the prognosis is concerned, it is important to diagnose the exact type of malformation in order to exclude associated anomalies, as well as the risk of development of malignancies in later life. The frequency of associated malformations of CCAM type 4 is unknown. Although the risk for development of malignancies from CCAM type 4 is not clear at the moment, the possible development of malignancies justifies prompt resection shortly after diagnosis, even in asymptomatic patients. A life-long follow-up in those patients who had a resection of CCAM in early childhood is recommended.

Cystic Adenomatoid Malformation of Lung, Congenita↗

PubMed2000

Analysis of muscle strength and bone structure in children with renal disease.

Bone structure and muscular strength of 30 children with renal disease were investigated by peripheral computed tomography and grip strength. Sixteen children suffered from nephrotic syndrome (NS) and had previously been treated with corticosteroids. Fourteen children suffered from chronic renal failure (CRF) ranging from mild renal failure to end-stage renal disease. Six children had received kidney transplants and corticosteroids for immunosuppression. There was a significant decrease in grip strength of children with NS (SD -0.91+/-1.5; P=0.042) and children with CRF (SD -1.38+/-1.4; P<0.001) compared with normal children. Furthermore, there was a significant correlation between cortical area and grip strength in all children with renal disease (r=0.92; P<0.0001). Trabecular bone mineral density did not correlate well with grip strength. These findings resemble results found in healthy children. Trabecular bone mineral density was significantly elevated in children with CRF compared with normal children (SD 1.14+/-1.4; P=0.008). Grip strength as a marker of muscle mass and cortical area as a marker of bone strength correlate well in children with renal disease, similar to the correlation in healthy children. Grip strength is significantly lower in children with NS and CRF compared with normal children. These data suggest that muscular impairment could be involved in renal osteopathy.

Adolescent↗

PubMed1999

Probucol for treatment of hyperlipidemia in persistent childhood nephrotic syndrome. Report of a prospective uncontrolled multicenter study.

In a prospective, uncontrolled multicenter study, we have evaluated the effects of probucol on hyperlipidemia, proteinuria, and glomerular filtration rate (GFR) in hyperlipidemic children with persistent nephrotic syndrome. Probucol was started for a total of 12 weeks in 8 children and for 24 weeks in 14 children. Lipoprotein profiles, serum malondialdehyde (MDA) levels, proteinuria, renal function, and electrocardiogram were monitored every 4 weeks. Side effects were recorded by questionnaire. Treatment was completed by 7 of 8 patients for 12 weeks and by 7 of 14 children for 24 weeks. After 12 weeks, the mean serum concentrations of triglycerides (-15%), total cholesterol (-25%), very low-density lipoprotein-cholesterol (-27%), low-density lipoprotein-cholesterol (-23%), and high-density lipoprotein-cholesterol (-24%), as well as apolipoprotein (apo) A-I (-19%), apo B (-21%), and MDA (-32%) were reduced. The positive effects of probucol on the lipoprotein profile persisted over 24 weeks; however, there was no significant effect on either proteinuria or GFR. In conclusion, probucol had beneficial effects on lipoproteins and lipid peroxidation, but improved neither proteinuria nor GFR. The drug was generally tolerated well, but had to be discontinued because of a prolonged QT interval in 4 of 22 patients.

Adolescent↗

PubMed1999

Intravenous iron treatment of renal anemia in children on hemodialysis.

Treatment of anemia in children with end-stage renal disease (ESRD) has been greatly facilitated by the introduction of recombinant human erythropoietin (rHuEPO). A major limiting factor in the treatment of renal anemia is sufficient iron supplementation. Eight children (aged 10-17 years) receiving hemodialysis were treated with intravenous iron (1 mg/kg per week) for 3 months. Hemoglobin (Hb), hematocrit (Hct), and serum ferritin levels were measured regularly. The mean Hct increased from 25% to 30%, the mean Hb increased from 7. 8 g/dl to 9.2 g/dl, and the mean ferritin level from 200 to 395 mg/dl. The mean EPO dosage could be tapered from 6,500 IU to 6,150 IU. No adverse side-effects were noted. Hence, in this uncontrolled study intravenous iron was an effective treatment for iron deficiency during rHuEPO therapy in children with ESRD on hemodialysis.

Adolescent↗

PubMed1999

Antagonistic effects of vitamin D and parathyroid hormone on lipoprotein lipase in cultured adipocytes.

The effects of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) (calcitriol) and parathyroid hormone (PTH) on synthesis and secretion of lipoprotein lipase (LPL) were studied in 3T3-L1 adipocytes. Expression of the vitamin D receptor was demonstrated by saturation kinetics with radiolabeled calcitriol. Incubation with calcitriol (10(-8) M) for up to 4 d resulted in a time-dependent significant increase in heparin-releasable LPL activity (LPLa) accompanied by a significant increase in LPL mRNA. In contrast, incubation with intact (1-84) PTH (10(-6) to 10(-9) M) produced a time- and dose-dependent significant decrease in LPLa, but no change in LPL mRNA. The effect of PTH (24-h incubation, 10(-8) M) could be prevented by the calcium channel blocker verapamil. Coincubation with both calcitriol and PTH at equimolar concentration (10(-8) M) resulted in an increase in LPLa and LPL mRNA. These data indicate an antagonistic role for calcitriol and PTH in the regulation of LPL, possibly mediated by intracellular calcium, which may contribute to the alterations in lipoprotein metabolism occurring in uremia.

Adipocytes↗

PubMed1998

Urinary excretion substances in patients with cystic fibrosis: risk of urolithiasis?

Patients with cystic fibrosis (CF) have an increased risk of urolithiasis/nephrocalcinosis. To determine potential mechanisms responsible, we studied the urinary excretion of lithogenic and stone-inhibitory substances and calculated the urinary saturation for calcium-oxalate (CaOx), brushite (CaHPO4), and uric acid (UA). We examined 24-h urines in 63 patients with CF (34 female, 29 male) aged 5 months to 36 years. Renal ultrasonography was performed at the time of urine collection. Hyperoxaluria was found in 25 patients (range 0.51-1.71 mmol/1.73 m2 per 24 h). Urinary Ca was increased in 13 patients (4.1-8.22 mg/kg per 24 h). Hyperuricosuria was found in 16 patients (5.2-18.0 mmol/1.73 m2 per 24 h) and hypocitraturia in 14 patients (0.07-1.14 mmol/1.73 m2 per 24 h). CaOx saturation was elevated in 26 patients, related to hyperoxaluria in 19 patients. CaHPO4 saturation was increased in 19 patients and UA saturation in 11 patients. Urolithiasis in situ was diagnosed in 1 patient; 3 patients previously had renal stones; 4 patients had present nephrocalcinosis. Elevated excretion of lithogenic substances and urinary supersaturation might lead to the higher risk of urolithiasis/nephrocalcinosis in patients with CF.

Adolescent↗

PubMed1998

Levamisole treatment in steroid-sensitive and steroid-resistant nephrotic syndrome.

Since 1992 we have treated 11 children with frequently relapsing steroid-sensitive (n=6) or steroid-resistant (n=5) nephrotic syndrome with levamisole. All had been non-responsive to other immunosuppressive medication before levamisole treatment. All steroid-sensitive patients had signs of steroid toxicity. At least 1 kidney biopsy had been performed prior to study in each patient. Five children had minimal glomerular changes and the other 6 focal segmental glomerular sclerosis. The patients were treated with levamisole (2.5 mg/kg per 48 h) for at least 2 months (up to 18 months, median 10 months). Two patients had additional immunosuppression (cyclosporine A) during levamisole treatment. All patients with steroid-sensitive nephrotic syndrome became free of proteinuria within 2 months and have remained in remission after discontinuation of levamisole (follow-up time 8-50 months, median 24 months). None of the children with steroid-resistant nephrotic syndrome experienced a remission. Side effects were observed in 2 patients and included a granulocytopenia and a severe psoriasis-like cutaneous reaction; both were reversible after discontinuation of levamisole. We conclude that levamisole is of benefit in steroid-sensitive nephrotic syndrome but not in steroid-resistant nephrotic syndrome.

Adjuvants, Immunologic↗

PubMed1998

A 12-year-old boy with fatal hemolytic-uremic-syndrome, excessive neutrophilia and elevated endogenous granulocyte-colony-stimulating-factor serum concentrations.

We report the case of a 12-year-old boy with fatal enteropathic hemolytic-uremic syndrome who developed excessive neutrophilia in the course of his disease, his leukocyte count exceeding 200,000/mm3. Neutrophilia, as it was observed in this case, is an extreme manifestation of a phenomenon, that is commonly observed in hemolytic-uremic syndrome [Salzmann et al. 1991]. Neutrophilia is suspected to be correlated with a bad prognosis [Walters et al. 1989], but further explanation of this phenomenon is needed. Other underlying diseases related with neutrophilia, especially hematologic malignancies, could be ruled out by far. We examined endogenous G-CSF serum concentrations of the HUS patient from day 6 to 13 in the course of the disease. The assayed concentrations were found to be elevated in the first two samples taken (peak level 340 pg/ml). In the samples taken after plasmapheresis had started, G-CSF concentrations were not found to be elevated. The peak of neutrophilia was reached short before death on day 13 of the disease. We also measured the serum G-CSF concentrations of 28 children aged 3 months to 12 years, who were treated with various infectious and noninfectious diseases in our hospital. In none of the examined samples was there a G-CSF serum concentration exceeding 50 pg/ml. The reported case shows evidence that the commonly observed coincidence of leukocytosis and HUS may reflect the role of G-CSF (and other cytokines) in the inflammatory process underlying the HUS.

Child↗

PubMed1997

Vitamin D receptor genotypes and changes of bone density in physically active German women with high calcium intake.

Polymorphisms at the vitamin D receptor (VDR) gene have been reported to mediate important differences in bone mineral density (BMD) and bone metabolism. In this longitudinal study we examined the relationships between VDR genotypes and bone metabolism, changes in BMD and changes in ultrasound transmission velocity in a population of healthy unrelated German women. The study population comprised 50 physically active women (aged 43.3 to 62.8 years, 14 premenopausal, 36 postmenopausal) with a daily calcium intake of (mean +/- SD) 1045 +/- 338 mg, who had earlier participated in a longitudinal study on the association of physical activity and bone density and bone turnover. Each participant was genotyped for the BsmI polymorphism at the VDR gene locus. Markers of bone turnover (alkaline phosphatase, osteocalcin, procollagen type I C-terminal propeptide, collagen type I C-terminal telopeptide, tartrate-resistant acid phosphatase) were measured at baseline. BMD (determined by peripheral quantitative computed tomography at the distal radius) and ultrasound transmission velocity through bone (at calcaneus, patella and thumb) were analysed at baseline and 15 months later. The genotypic groups did not differ significantly (p > 0.05) in any of the parameters determined at baseline. Neither were there any differences between these groups in the changes of BMD or ultrasound transmission velocity during the study period. Thus, we conclude that in physically active German women with a relatively high calcium intake the impact of VDR genotypic polymorphisms on bone density, bone metabolism and changes in bone density may be of limited importance.

Alleles↗

PubMed1996

Taurine reduces experimental liver injury after cold ischemic preservation and a period of rewarming prior to reperfusion.

Livers of male Wistar rats (250-300 g) were isolated and flushed with 10 ml of Ringer's solution and 10 ml of UW preservation solution. Then the organs were stored for 24 h at 4 degrees C in UW solution. Livers of Group 1 were rinsed with 10 ml of Ringer's solution and reperfused after hypothermic storage with oxygenated Krebs-Henseleit solution (95% O2; 5% CO2) in a nonrecirculating system at constant pressure (10 mmHg) and 37 degrees C. Livers of Group 2 were incubated for 30 min at 37 degrees C prior to reperfusion, in order to simulate rewarming of the organ upon surgical implantation. Livers of Group 3 were treated like Group 2, but taurine was admixed to the UW solution (1 mM). Livers of Group 1 showed little signs of a preservation/reperfusion injury, with low enzyme activities of the parenchymal ALT and endothelial purine nucleoside phosphorylase (PNP) in the postischemic rinse solution (ALT: 19.9 +/- 12.4; PNP: 3.3 +/- 0.4 U/liter), adequate portal flow values about 3 ml/g/min and high O2 uptake at the end of the experiment (VO2: 3.2 +/- 0.4 ml/100g/min). Livers of Group 2 exhibited nearly tenfold higher enzyme activities in the rinse solution (ALT: 247.0 +/- 94.7*; PNP: 29.5 +/- 17.0* U/l) and disturbed tissue perfusion with significantly reduced flow values of about 2 ml/g/min during the first 10 min of reperfusion. As a result, the recovery of O2 uptake was only 2.2 +/- 0.3 ml/100 g/min*. Addition of taurine (Group 3) resulted in a significant reduction of the enzyme loss (ALT: 96.2 +/- 50.0#; PNP:12.4 +/- 7.0# U/liter) and improved portal flow values and O2 uptake at the end of reperfusion (2.7 +/- 0.3 ml/100 g/min#). The results give evidence for the importance of the rewarming period after hypothermic storage, which is inevitable during implantation of the organ in vivo. Taurine seems to exert a protective effect, affecting both the vascular endothelium and parenchymal tissue (*p < 0.05 vs Group 1; # p < 0.05 vs Group 2).

Adenosine↗

PubMed1996

Case of the month.

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Antibodies, Viral↗

PubMed1996

Aplasia of the cerebellar vermis associated with chronic renal disease. A report of six cases and a review of the literature.

UNLABELLED: We report six patients with aplasia or hypoplasia of the cerebellar vermis with early symptoms consisting of psychomotor retardation, nystagmus and severely reduced visual acuity due to congenital amaurosis. At age 5.6-12.1 years, five of these patients developed symptoms of chronic renal failure due to renal maldevelopment. CONCLUSION: Children presenting with vermis aplasia should be monitored for associated disorders, especially renal disease.

Blindness↗

PubMed1996

Oxalate elimination via hemodialysis or peritoneal dialysis in children with chronic renal failure.

Oxalate elimination and oxalate dialysance via hemodialysis (HD) or peritoneal dialysis (CAPD) has not been studied in detail in pediatric patients. We studied plasma oxalate, oxalate elimination, and oxalate dialysance in 15 infants and children undergoing CAPD (9 female, 6 male, aged 9 months to 18 years) and in 10 children on HD (4 female, 6 male, aged 7-18 years). Two children in each group had primary hyperoxaluria (PH). The mean duration of dialysis prior to examination was 12 +/- 11 months in CAPD and 31 +/- 23 months in HD patients. Bicarbonate HD was performed 5 h three times a week, CAPD consisted of five daily exchanges in 5 patients and four changes in the remaining 10 children (dwell volume 40 ml/kg body weight, 2.3 g/l glucose). Although oxalate dialysance was significantly higher in HD (mean 115.6 ml/ min per 1.73 m2 in HD versus 7.14 ml/min in CAPD), mean oxalate elimination per week was not different between both renal replacement therapies (3,478 mumol/1.73 m2 surface area/week in CAPD versus 3,915 mumol/1.73 m2 per week in HD). Oxalate elimination in patients with PH was between 6,650 and 9,900 mumol/week. Plasma oxalate remained elevated in both procedures [28-84 mumol/l in CAPD (92/148 in PH) and 33-101 mumol/l in HD (70/93 in PH)]. Oxalate elimination can be increased by a more frequent hemodialysis regimen.

Adolescent↗

PubMed1996

Influence of muscle strength on bone strength during childhood and adolescence.

In connection with the prevention of osteoporosis, paediatrics is challenged with ensuring the optimal formation of the skeletal system with maximal bone strength during childhood and youth. Biomechanical use represents the most important stimulus for activating the skeletal system. The measurement of muscle strength (grip strength) in 97 females aged 3-62 years and 71 males aged 3-61 years showed an age-dependent course. On the whole, males have greater strength with a more pronounced increase after puberty, reaching a peak maximum at 25-30 years. Females show a more moderate increase after puberty. In a pilot study, bone strength (as bone strength index-BSI) was analysed at the distal radius using peripheral quantitative computerized tomography (pQCT). BSI was calculated on the basis of the geometric data of the polar moment of resistance in combination with the cortical bone density. BSI values increase with age and reach a peak maximum at 25-30 years. There was a highly significant correlation between BSI and grip strength (r = 0.87). These relationships are especially interesting for therapeutic concepts differentiating between direct and indirect (via the muscle system) influences on the skeletal system. The non-invasive bone strength analysis in combination with muscle strength offer new perspectives for the evaluation of the functional muscle-bone unit.

Adolescent↗

PubMed1996

Pneumococcal vaccine in children and young adults with chronic renal disease.

BACKGROUND: Pneumococcal vaccination has been recommended for immunocompromised children over 2 years including patients with chronic renal disease. However, the effect of vaccination and revaccination is variable and the indication for immunization is a subject of controversy. METHODS: Forty children and young adults with chronic renal diseases (including the idiopathic nephrotic syndrome, chronic renal failure, patients undergoing dialysis and after transplantation) were vaccinated with a 23-valent pneumococcal vaccine. The efficacy of the vaccine was evaluated by measuring antibody titres before and 4 weeks, 6 months, and 12 months after vaccination. Twenty-two patients were submitted to a revaccination 1 year after the first vaccination. RESULTS: A sufficient immune response, defined as an at least fourfold increase of postvaccinal antibody titres and an antibody titre > 200, was observed in 83% of the patients 4 weeks after vaccination, but only in 68% after 6 months, and in 48% after 1 year. Revaccination produced a significant immune response in 11/22 patients (50%) followed by a rapid decline of antibody levels within 6 months. Both vaccinations were well tolerated. CONCLUSIONS: The currently available vaccine is without major side-effects and effective in producing a significant immune response. Antibody levels should be monitored in vaccinated patients with chronic renal diseases considering the rapid decline as early as 6 months after vaccination. Evaluation of the efficacy of revaccination in these patients requires further investigations.

Adolescent↗

PubMed1995

Acute glaucoma and intracranial hypertension in a child on long-term peritoneal dialysis treated with growth hormone.

A 7-year-old boy with end-stage renal disease on long-term peritoneal dialysis is described. The child developed intracranial hypertension and acute glaucoma during therapy with recombinant human growth hormone (rhGH), 18 months after the onset of treatment. Symptoms developed within 1.5 days and required neurosurgical treatment to reduce the intracranial hypertension because of imminent impaction of the cerebellum and brain stem. After ventricular cerebrospinal fluid drainage and cessation of growth hormone, all symptoms of intracranial hypertension and increased intraocular pressure disappeared. To our knowledge this is the first report of intracranial hypertension or hydrocephalus and acute glaucoma during rhGH therapy. Continuous and long-term control of the ophthalmological and neurological status of patients treated with rhGh is indicated.

Acute Disease↗

PubMed1995

Urinary excretion of galactosyl-hydroxylysine is a marker of growth in children.

Galactosyl-hydroxylysine (Gal-Hyl) is the predominant product of the posttranslational glycosylation of skeletal collagen. Urinary Gal-Hyl excretion is regarded as a marker of bone resorption in adults, but little information is available on the validity of this parameter in pediatric age groups. Using 24-h urine samples from 88 healthy children and adolescents ages 4-18 yr, reference ranges were established for this age group, and values were compared with measurements in children with overt GH deficiency (n = 14) or Ullrich-Turner syndrome (n = 21). When expressed relative to body weight (Gal-Hyl/wt), urinary Gal-Hyl excretion was 3.2 to 4.7 times higher in subjects 4-16 yr of age than in adults. Highest values were observed in very young children and during the pubertal growth spurt. In the total population, urinary Gal-Hyl/wt was closely related to growth velocity (r = 0.72) and significantly correlated with the urinary excretion of both hydroxyproline (r = 0.74) and deoxypyridinoline (r = 0.88; P < 0.001 each). Urinary Gal-Hyl/wt was significantly lower in children with GH deficiency or Ullrich-Turner syndrome than in healthy children (P < 0.001 each). The urinary excretion of Gal-Hyl was significantly correlated with growth velocity in GH-deficient children (r = 0.69; P = 0.004) but not in patients with Ullrich-Turner syndrome. In the latter, the increase in urinary Gal-Hyl excretion after 3 months of treatment with recombinant human GH correlated significantly with the increase in growth velocity after 12 months of treatment (r = 0.76; P = 0.002). We conclude that the urinary excretion of Gal-Hyl is a valid and potentially useful index of skeletal growth in children.

Adolescent↗