Profiling of historical rag papers by their non-cellulosic polysaccharide composition

Hemicellulose and pectin are noteworthy components of historical European rag papers, and have not been studied in detail so far. Rag papers were made from used textiles, and fiber-based utilities, such as ropes and bags. These had been prepared until the mid-19th century from plant-based fibers. Their polysaccharide composition could relate to their condition and history. This information can be expected to hold importance for the preservation and conservation of historical objects. We investigated a collection of rag papers of different age for their composition of non-cellulosic polysaccharides, and compared the findings with modern rag papers and wood pulps. Furthermore, a non-destructive determination of the hemicellulose and pectin content by near-infrared spectroscopy was developed. Historical rag papers had a lower hemicellulose/pectin content than pulps; the fractions of rhamnose, galactose, and arabinose were higher, while xylose was lower. In modern rag papers, xylose tended to be at the higher end of the range, which suggests a degradation of hemicelluloses/pectin over time or a change in raw materials and manufacturing. Rag papers also showed higher crystallinity than wood pulp papers. These findings provide insights into rag paper characteristics and offer potential classification methods.

A step towards tuning the jute fiber structure and properties by employing sodium periodate oxidation and coating with alginate

This paper outlines a novel simple protocol for tuning the structure and properties of jute using sodium periodate (NaIO4) oxidation and coating with alginate. When compared to the raw jute, fabrics oxidized with a 0.2 or 0.4 % NaIO4 solution for 30-120 min exhibited an increased aldehyde group content (0.185 vs. 0.239-0.398 mmol/g), a significantly increased negative zeta potential (from -8.57 down to -20.12 mV), a slight disruption of fiber crystallinity, 15.1-37.5 % and 27.9-49.8 % lower fabric maximum force and stiffness, respectively. Owing to the removal of hydrophobic surface barrier, decreased crystallinity index and the presence of micropores on the fabrics' surfaces, oxidized fabrics have a 22.3-29.6 % improved ability for moisture sorption compared to raw fabric. Oxidized fabrics characterized by very long wetting times and excellent antioxidant activities (> 98 %), can find applications as hydrophobic packaging materials. To further extend the utilization of jute in biocarpet engineering such as water-binding geo-prebiotic supports, oxidized fabrics were coated with alginate resulting in 7.9-24.9 % higher moisture sorption and 352-660 times lower wetting times than their oxidized counterparts. This modification protocol has never been applied to lignocellulosic fibers and sheds new light on obtaining jute fabrics with tuned structure and properties intended for various applications.

The influence of the tooth preparation finish line position on the expression of matrix metalloproteinase-9 and the presence of periodontopathogens in the gingival crevicular fluid

OBJECTIVE

The objective of the study was to determine the concentration of matrix metalloproteinase 9 (MMP-9) and changes in the presence of periodontopathogens in the gingival crevicular fluid before and after tooth preparation with the subgingival and equigingival finish line position.

PATIENTS AND METHODS

The clinical prospective study included 20 subjects with an indication for upper canine preparation, with the subgingival (group 1) and equigingival finish line (group 2). Samples were taken in four observation intervals: 5 minutes before (control samples), as well as 15 minutes, 24 and 72 hours after tooth preparation (experimental samples). Measurement of MMP-9 was done using Enzyme-linked Immunosorbent Assay (ELISA). The presence of bacteria in the gingival fluid was proven by the Polymerase chain reaction (PCR) analysis.

RESULTS

The MMP-9 values did not differ statistically significantly between the groups (p=0.524). The MMP-9 values showed a statistically significant difference in the given observation period (p<0.001) with a significant linear increase in values (p<0.001). A significant quadratic trend recorded a decrease in the MMP-9 values 15 minutes after preparation, and an increase 24 hours after preparation, without a significant difference in the interaction between groups (p=0.392). After preparation, a significant difference in the presence of periodontopathogens was confirmed, i.e., a decrease in the presence of Prevotella intermedia (p=0.025) and Tannerella forsythia (p=0.016) in group 1, and an increase in the presence of Aggregatibacter actinomycetemcomitans in both groups (p=0.029, p=0.026).

CONCLUSIONS

The study is a good basis for determining the influence of tooth preparation on gingival inflammation, with therapeutic (choice of preparation technique) and preventive significance regarding the protection of the periodontal tissue from possible iatrogenic damage.

Biodegradable Cellulose/Polycaprolactone/Keratin/Calcium Carbonate Mulch Films Prepared in Imidazolium-Based Ionic Liquid

Ionic liquid 1-butyl-3-methylimidazolium chloride [BMIM][Cl] was used to prepare cellulose (CELL), cellulose/polycaprolactone (CELL/PCL), cellulose/polycaprolactone/keratin (CELL/PCL/KER), and cellulose/polycaprolactone/keratin/ground calcium carbonate (CELL/PCL/KER/GCC) biodegradable mulch films. Attenuated Total Reflectance Fourier-Transform Infrared (ATR-FTIR) spectroscopy, optical microscopy, and Field-Emission Scanning Electron Microscopy (FE-SEM) were used to verify the films' surface chemistry and morphology. Mulch film made of only cellulose regenerated from ionic liquid solution exhibited the highest tensile strength (75.3 ± 2.1 MPa) and modulus of elasticity of 944.4 ± 2.0 MPa. Among samples containing PCL, CELL/PCL/KER/GCC is characterized by the highest tensile strength (15.8 ± 0.4 MPa) and modulus of elasticity (687.5 ± 16.6 MPa). The film's breaking strain decreased for all samples containing PCL upon the addition of KER and KER/GCC. The melting temperature of pure PCL is 62.3 °C, whereas that of CELL/PCL film has a slight tendency for melting point depression (61.0 °C), which is a characteristic of partially miscible polymer blends. Furthermore, Differential Scanning Calorimetry (DSC) analysis revealed that the addition of KER or KER/GCC to CELL/PCL films resulted in an increment in melting temperature from 61.0 to 62.6 and 68.9 °C and an improvement in sample crystallinity by 2.2 and 3.0 times, respectively. The light transmittance of all studied samples was greater than 60%. The reported method for mulch film preparation is green and recyclable ([BMIM][Cl] can be recovered), and the inclusion of KER derived by extraction from waste chicken feathers enables conversion to organic biofertilizer. The findings of this study contribute to sustainable agriculture by providing nutrients that enhance the growth rate of plants, and hence food production, while reducing environmental pressure. The addition of GCC furthermore provides a source of Ca²⁺ for plant micronutrition and a supplementary control of soil pH.

Obtaining Medical Textiles Based on Viscose and Chitosan/Zinc Nanoparticles with Improved Antibacterial Properties by Using a Dielectric Barrier Discharge

This study aimed to obtain functional viscose textiles based on chitosan coatings with improved antibacterial properties and washing durability. For that reason, before functionalization with chitosan/zinc nanoparticles (NCH+Zn), the viscose fabric was modified by nonthermal gas plasma of dielectric barrier discharge (DBD) to introduce into its structure functional groups suitable for attachment of NCH+Zn. NCH+Zn were characterized by measurements of hydrodynamic diameter and zeta potential and AFM. DBD-plasma-modified and NCH+Zn-functionalized fabrics were characterized by zeta potential measurements, ATR-FTIR spectroscopy, the calcium acetate method (determination of content of carboxyl and aldehyde groups), SEM, breaking-strength measurements, elemental analysis, and ICP-OES. Their antibacterial activity was determined under dynamic contact conditions. In addition to SEM, the NCH+Zn distributions on viscose fabrics were also indirectly characterized by measuring their absorbent capacities before and after functionalization with NCH+Zn. Washing durability was monitored through changes in the zeta potential, chitosan and zinc content, and antibacterial activity after 1, 3, and 5 washing cycles. The obtained results showed that DBD plasma modification contributed to the simultaneous improvement of NCH+Zn sorption and antibacterial properties of the viscose fabric functionalized with NCH+Zn, and its washing durability, making it suitable for the production of high-value-added medical textiles.

Biosorbents from Plant Fibers of Hemp and Flax for Metal Removal: Comparison of Their Biosorption Properties

Lignocellulosic fibers extracted from plants are considered an interesting raw material for environmentally friendly products with multiple applications. This work investigated the feasibility of using hemp- and flax-based materials in the form of felts as biosorbents for the removal of metals present in aqueous solutions. Biosorption of Al, Cd, Co, Cu, Mn, Ni and Zn from a single solution by the two lignocellulosic-based felts was examined using a batch mode. The parameters studied were initial metal concentration, adsorbent dosage, contact time, and pH. In controlled conditions, the results showed that: (i) the flax-based felt had higher biosorption capacities with respect to the metals studied than the hemp-based felt; (ii) the highest removal efficiency was always obtained for Cu ions, and the following order of Cu > Cd > Zn > Ni > Co > Al > Mn was found for both examined biosorbents; (iii) the process was rapid and 10 min were sufficient to attain the equilibrium; (iv) the efficiency improved with the increase of the adsorbent dosage; and (v) the biosorption capacities were independent of pH between 4 and 6. Based on the obtained results, it can be considered that plant-based felts are new, efficient materials for metal removal.

Unnecessary prescribing of antibiotics to healthy/asymptomatic school-age carriers of potentially pathogenic bacteria

OBJECTIVES

To re-draw attention to the unnecessary prescribing of antibiotics.

METHODS

We monitored nasopharyngeal colonization by 3 potentially pathogenic bacteria, Streptococcus pyogenes, Streptococcus pneumoniae, and Haemophilus influenzae type b in 81 children between the ages of 6 and 7 years who attended the same primary school. The children's health status was also monitored, without using antimicrobial treatment for healthy/asymptomatic carriers. Nasopharyngeal swabs were collected on 6 occasions during autumn months, from mid-September to mid-December 2016. The children who fell ill during the study were treated at the Ear, Nose and Throat Clinic, Sisters of Mercy University Hospital Center, Zagreb, Croatia.

RESULTS

Four hundred and sixty-three  nasopharyngeal swabs were collected. Each child had at least one positive swab result. Bacterial colonization with Streptococcus pyogenes had the highest colonization rate. During the study, 83% of the children were healthy/asymptomatic carriers with no clinical signs of disease,  while 17% became ill. The statistical results showed that the increase in all examined bacteria was statistically significant.

CONCLUSIONS

  Our  study results showed that positive bacterial findings in nasopharyngeal swabs from clinically healthy carriers were not an indication for antibiotic therapy.

Hypertrophic recurring lichen planus of the external auditory canal

INTRODUCTION

We report a case of unilateral progressive primary hypertrophic lichen planus of the external auditory canal requiring several surgical interventions to deal with constant pruritus, otorrhoea, stenosis and conductive hearing loss.

CASE SUMMARY

A 58-year-old woman was initially treated with meatoplasty for suspected chronic obliterating otitis externa. She remained symptom-free for 5 years, before the disease recurred, affecting other body surfaces as well. Otorrhoea, conductive hearing loss and pruritus worsened, and a canal wall down tympanomastoidectomy was performed, removing the skin of the external auditory canal and the tympanic membrane completely. Lichen planus was confirmed histopathologically.

DISCUSSION

Very few surgical results have been published on stenosis of the external auditory canal caused by lichen planus. Complete medial external auditory canal skin elevation and removal with postoperative split-skin grafting is advised for initial treatment. We discuss treatment options and surgical outcome after initial surgical failure.

Serum Neutrophil Gelatinase-Associated Lipocalin and Urinary Kidney Injury Molecule-1 as Potential Biomarkers of Subclinical Nephrotoxicity After Gadolinium-Based and Iodinated-Based Contrast Media Exposure in Pediatric Patients with Normal Kidney Function

Background

New renal biomarkers such as neutrophil gelatinase-associated lipocalin (NGAL) and kidney injury molecule-1 (KIM-1) show promise in early diagnosis of contrast media induced acute kidney injury (CI-AKI). The purpose of our study was to compare the subclinical nephrotoxicity (a condition without changes in standard renal biomarkers) of gadolinium-based contrast media (Gd-DTPA, gadopentetate dimeglumine) and iodinated-based contrast media (iopromide) in pediatric patients with normal kidney function.

Material/Methods

The first group (n=58) of patients included in the study were undergoing angiography with iopromide, and the second group (n=65) were undergoing magnetic resonance (MR) angiography/urography with Gd-DTPA administration. The concentrations of NGAL and KIM-1 were measured four times in the urine (pre-contrast, then at four hours, 24 hours, and 48 hours after contrast administration), and serum NGAL was measured at 0 (baseline), 24 hours, and 48 hours after contrast exposure.

Results

After 24 hours, serum NGAL increase of ≥25% was noticed in 32.6% of the patients in the iopromide group and in 25.45% of the patients in the gadolinium group, with significantly higher average percent of this increase in first group (62.23% vs. 36.44%, p=0.002). In the Gd-DTPA group, we observed a statistically significant increase in urinary KIM-1 24 hours after the procedure. Normalized urinary KIM-1, 24 hours after contrast exposure, was a better predictive factor for CI-AKI than other biomarkers (AUC 0.757, cut off 214 pg/mg, sensitivity 83.3%, specificity 54.2%, p=0.035).

Conclusions

In children with normal renal function, exposure to iodinated-based and gadolinium-based media might lead to subclinical nephrotoxicity, which could be detected using serum NGAL and urinary KIM-1.

Granulomatous interstitial nephritis associated with influenza A: H1N1 infection--A case report

INTRODUCTION

The causes of acute tubulointerstitial nephritis can be grouped into four broad categories: medications, infections, immunologic diseases, or idiopathic processes. Here we report a 17-year-old female who developed acute kidney injury (AKI) due to granulomatous interstitial nephritis (GIN) associated with influenza A: H1N1 infection.

CASE OUTLINE

The illness presented after two weeks of respiratory tract infection, skin rash and hypermenorrhea. On admission the patient was febrile, with bilateral pedal edema, macular skin rash, and auscultatory finding that suggested pneumonia. Laboratory investigations showed normocytic anemia, azotemia, hematuria and proteinuria. Renal ultrasound was normal. Antinuclear antibodies, antineutrophil cytoplasmic antibodies, lupus anticoagulant, antiphospholipid antibodies were negative with normal complement. Urine cultures including analysis for Mycobacterium tuberculosis were negative. The diagnosis of influenza A: H1N1 infection was made by positive serology. A kidney biopsy showed interstitial nephritis with peritubular granulomas. Glomeruli were normal. Staining for immunoglobulins A, M, G, and F was negative. The girl was treated with oseltamivir phosphate (Tamiflu; Genentech, Inc., South San Francisco, CA, USA) for five days, as well as with tapered prednisone after a starting dose of 2 mg/kg. The treatment resulted in a complete remission during two years of follow-up.

CONCLUSION

We present a severe but reversible case of GIN and AKI associated with influenza A: H1N1 infection. Although a causal effect cannot be confirmed, this case suggests that influenza A: H1N1 should be considered in the differential diagnosis of GIN manifested with AKI in children.

Clinical and audiological findings in children with acute otitis media

CONCLUSION

It is recommended to perform follow-up tympanometry and if necessary tonal audiometry in children who have normal plain otoscopy findings after recovering from acute otitis media (AOM). Children with Type B tympanogram, 3 months following the onset of AOM, are very likely to have a conductive hearing loss. Type B tympanogram is a much better indicator of effusion in the middle ear compared to plain otoscopy.

OBJECTIVE

This study was undertaken to investigate the frequency and duration of middle ear effusion in children following an episode of acute otitis media, to track changes in tonal audiometry and tympanometry findings in the post-AOM period, and recognize the optimal timing for performing both tests.

METHODS

In this study, 125 children aged 5-7 years with bilateral AOM were randomly selected and separately followed up for 3 months. The children underwent six ear, nose, and throat (ENT 1-6) examinations, six tympanometries (TM 1-6), and three tonal audiometries (TA 1-3). Evaluation of nasopharynx was done at the ENT 1 examination. Children who received ventilation tubes were followed for 21 month altogether.

RESULTS

At the first otoscopy, pathological findings were recorded in 250 ears/125 children (100.0%). The number of pathological otoscopy findings decreased at each subsequent examination. At ENT 6 all children had normal otoscopy findings. Type B tympanogram was detected in 49/250 (19.6%) ears at TM 6, performed 3 months following the onset of the disease. At the TA 1 conductive hearing impairment was recorded in 158/250 (63.2%) ears, at TA 2 in 66/250 (26.4%), and at TA 3 in 39/250 (15.6%). Most of them were associated with Type B tympanogram.

Influence of psycho-social factors on the emergence of depression and suicidal risk in patients with schizophrenia

BACKGROUND

The aim of this study was to investigate the influence of certain psychosocial factors - insight, psycho-education, family and social support, loneliness and social isolation - on the appearance of depression and suicidal risk in schizophrenia.

SUBJECTS AND METHODS

This was a cross-sectional study that comprised hospitalized patients with schizophrenia in the initial remission phase. The assessment of depression and suicidal risk was made by applying a semi-structured psychiatric interview that included scrutinized factors (insight, psycho-education, family and social support, loneliness and social isolation), Positive and Negative Syndrome Scale (PANSS), and Calgary Depression Scale for Schizophrenia (CDSS). On the basis of the assessment results, the sample was divided into two groups: Group of patients with depression and suicidal risk in schizophrenia (N = 53) and Control group (N = 159) of patients with schizophrenia without depression and suicidal risk.

RESULTS

In the Group of patients with depression and suicidal risk, compared with the Control group, there was significantly higher frequency of insight in the mental status (χ² = 31.736, p < 0.001), number of patients without psycho-education (χ² = 10.039, p = 0.002), deficit of family support (χ² = 13.359, p = 0.001), deficit of social support (χ² = 6.103, p=0.047), loneliness (χ² = 6.239, p = 0.012), and social isolation (χ² = 47.218, p < 0.001). Using the model of multi-variant logistic regression, insight, deficit of psycho-education and social isolation (p < 0.05) were identified as predictors of depression and suicidal risk in schizophrenia.

CONCLUSIONS

This study shows that considered psycho-social factors - insight in the mental status, lack of psycho-education, as well as social isolation - could be predictors for appearance of depression and suicidal risk in schizophrenia.

[Prosthetic rehabilitation in patient with forced class III malocclusion]

The paper presents clinical case of 63 years old edentulous patient with slight class III malocclusion. For 15 years he was using inadequately fabricated dentures causing forced severe class III malocclusion. Forced progeny was corrected by newly fabricated dentures which restored normal orofacial function and facial harmony.

Nasopharyngeal bacterial flora in healthy preschool children during winter-spring months

The paper aimed to determine the incidence of colonization of Streptococcus pyogenes, Streptococcus pneumoniae, Haemophilus influenzae type b and Neisseria meningitidis in the nasopharynges of healthy children in two preschool institutions during winter and spring months, without using antimicrobial treatment or serotyping of these bacteria. In addition to colonization of the above bacteria, the research that continued for 3 months monitored the length of their persistence in and disappearance from children's nasopharynges, children's health statuses, and provision of adequate medical interventions in children demonstrating clinical signs of disease. The ultimate aim of the paper was based on contributing to clearer and more accurate determination of a medical procedure in case of a positive result for bacteria intended to be found in the nasopharynx of a healthy child who spends time in a preschool institution.

Hyperlipidemia, oxidative stress, and intima media thickness in children with chronic kidney disease

BACKGROUND

The roles of dyslipidemia and oxidative stress in the early phases of atherosclerosis were tested in children with chronic kidney disease (CKD). Intima media thickness of common carotid arteries (cIMT) is used as a measure of early atherosclerosis.

METHODS

Fifty-two pediatric CKD patients were enrolled in the study (10 with chronic renal failure [CRF], 22 with a renal transplant [RT], 20 with chronic hemodialysis (cHD) patients, and 36 healthy children (control group, CG). Lipid status, oxidative stress, and paraoxonase 1 (PON1) status were assessed. cIMT was measured by ultrasound, adjusted for age and sex, and presented as standard deviation scores (SDS).

RESULTS

Children with CKD had disturbed lipid content, which was most pronounced in cHD children, with higher free cholesterol and triglycerides compared with healthy children. Oxidative stress was markedly increased (malodialdehyde [MDA, μmol/L]: CRF 1.50 ± 0.26, RT 1.55 ± 0.40, cHD 1.77 ± 0.34, CG 0.97 ± 0.33, p < 0.001) and antioxidative defense was compromised (superoxide dismutase [SOD, U/L]: CG 120 ± 21, CRF 84 ± 25, RT 93 ± 12, cHD 119 ± 37, p < 0.001). Multiple linear regression analysis showed that a model that included disease duration, blood pressure, urea, lipid, and oxidative status parameters accounted for more than 90% of the variability of cIMT-SDS.

CONCLUSIONS

Early atherosclerosis in CKD children is caused, at least in part, by dyslipidemia and oxidative stress. Monitoring of vessel wall changes, along with assessment of oxidative stress status and high density lipoprotein (HDL) functionality is necessary to ensure better therapeutic strategies for delaying atherosclerotic changes in their asymptomatic phase.

Benign paroxysmal vertigo in childhood

The aim of the paper is to describe the clinical picture of benign paroxysmal vertigo (BPV) in childhood. BPV in childhood often goes unrecognized in spite of the fact that vertigo and balance disorders are not uncommon in children. Four cases are described with clinical examination findings between the attacks.

Shiga toxin-producing Escherichia coli O171:H25 strain isolated from a patient with haemolytic uraemic syndrome

Shiga toxin-producing Escherichia coli (STEC) strains of O157:H7 serotype are a predominant cause of haemolytic uraemic syndrome (HUS) worldwide, but strains of non-O157 serotypes can also be associated with serious disease. Some of them are associated with outbreaks of HUS, others with sporadic cases of HUS, and some with diarrhoea but not with outbreaks or HUS. A large number of STEC serotypes isolated from ruminants and foods have never been associated with human disease. In this study we characterize a STEC strain belonging to serotype O171:H25 that is responsible for a case of HUS. This strain has a single Shiga toxin gene encoding Stx2 toxin, and hlyA gene, but is eae-negative.

Antibiotic resistance of uropathogens in newborns and young children with acute pyelonephritis

INTRODUCTION

Urinary tract infection is common in childhood. Depending on the localization of the infection, severity of its clinical presentation and possible acute and long-term complications, it may be described as either acute cystitis or acute pyelonephritis.

OBJECTIVE

The aim of this study was to assess the resistance patterns of uropathogens during the last 5 years in newborns and young children with acute pyelonephritis.

METHODS

Uropathogens resistance to commonly usable anti-microbial agents (ampicillin, a combination of sulphamethoxasole and trimethoprim, cephalexin, ceftriaxone, cefotaxime, ceftazidime, gentamycin, amikacin, ciprofloxacin, imipenem and nalidixic acid) was retrospectively studied in newborns and young children treated during early (2005-2007) and late (2008-2009) study periods. Anti-bacterial susceptibility testing of the urine isolates was performed by the standard disc diffusion method.

RESULTS

117 newborns and 294 children aged 9.3 +/- 0.7 months were treated during early (n=136) or late (n=275) study period due to the first episode of acute pyelonephritis. Escherichia coli was the most common bacterial pathogen (85.5%). Compared to children older than one month, newborns had higher degree of antibacterial resistance to 2nd and 3rd generation cephalosporins, aminoglycosides, and nalidixic acid during early, and to ceftazidime, aminoglycosides and nalidixic acid during late study period. Also, multidrug resistance was more common in newborns during the early study period.

CONCLUSION

Newborns had higher rate of antibacterial resistance than young children.The progressive increase of anti-microbial resistance in children with acute pyelonephritis is of great concern.

Long-term functional outcomes after 10 years of bilateral cochlear implantat use

The aims were to determine the benefit of bilateral cochlear implantation in a 20 years old patient implanted in Croatia on hearing and speech development. The male patient, after 10 years of deafness, got cochlear implants Med-EL Combi 40+ on both sides in one-stage surgery. The etiology of his deafness was posttraumatic meningitis. Auditory capacity and speech recognition tests were performed for both ears separately and together Average hearing level on the right ear with right cochlear implant switched on started at 62 dB 1 month after the cochlear implantation and was on 55 dB after 10 years. Average hearing level on the left ear with left cochlear implant switched on started at 55 dB 1 month after the cochlear implantation and was on 32 dB after 10 years. Average hearing level on the both ears with 2 cochlear implants switched on started at 35 dB 1 month after the cochlear implantation and was on 27 dB after 10 years. Long-term functional outcomes with bilateral cochlear implantation provides advantages over unilateral implantation including improved hearing level, speech perception in noise and improved sound localization.

Microalbuminuria in relation to metabolic control and blood pressure in adolescents with type 1 diabetes

INTRODUCTION

The objective of this study was to assess the frequency of microalbuminuria and the relationship with other risk factors for the development of diabetic nephropathy.

MATERIAL AND METHODS

Our cross-section study involved a group of 60 adolescence of both sexes, mean age 15.3 ±2.43 years with mean duration of diabetes 7.74 ±3.44 years. Albumin excretion rate was measured on 2-3 samples of the first morning urine in the period below 6 months and persistent microalbuminuria was defined if its increased in two out of three urine specimens. Ambulatory blood pressure was monitored (ABPM, SpaceLabs 90207).

RESULTS

Microalbuminuria developed in 13.3% of adolescents with mostly completed sexual development, statistically significantly poorer metabolic control (9.79% vs. 8.7%) and higher BMI (23.59 kg/m(2) vs. 20.85 kg/m(2)) than in the patients with normoalbuminuria. The mean night-time systolic blood pressure (SBP) was statistically significantly higher in microalbuminuric patients than in normoalbuminurics. The nocturnal dip was reduced in 41.7% of our patients; 38.5% of nondippers were in normoalbuminuric and 62.5% in microalbuminuric patients.

CONCLUSIONS

Diabetic adolescents require particular attention in order to minimize the factors such as high HbA(1c), elevated body mass index and night-time SBP in the development of incipient nephropathy.

Infantile nephropathic cystinosis

INTRODUCTION

Infantile nephropathic cystinosis (INC) is a metabolic disorder due to impaired carrier-mediated transport of cystine out of cellular lysosomes.

OBJECTIVE

To examine the prevalence and clinical characteristics of INC in paediatric patients with endstage renal disease (ESRD) in Serbia and give a recent statement of the disease.

METHODS

ESRD database of the Centre for Paediatric Renal Replacement Therapy (RRT) in Serbia was used to identify all patients with INC who started RRT before age of 19 years during the period January 1980 - December 2008; their records concerning clinical characteristics, therapy and outcome were evaluated.

RESULTS

Only three of 298 paediatric patients with ESRD had INC. The first signs of the illness were recognised during infancy. Fancony syndrome was diagnosed in the second year, but the diagnosis of cystinosis was delayed at mean 6 years. ESRD occurred in the first decade of life. All patients underwent cadaver kidney transplantation. At the end of the study period all patients were alive. A 31-year-old female patient was on maintenance chemodialysis due to graft failure after functioning for 11 years. She was growth retarded, single, unemployed, with severe signs of renal dystrophy. Two male patients (14.3 and 14.7 years old) had normal graft function, normal education, and good quality of life, although they were also severe growth retarded.

CONCLUSION

The prevalence of infantile nephropathic cystinosis is low in Serbia. The diagnosis of cystinosis was delayed in all patients, although they exhibited the typical course of the disease.

The IL-6 -174G/C polymorphism and renal scarring in children with first acute pyelonephritis

Urinary tract infections (UTI) are common in infants and children and may result in serious complications, such as renal scarring, hypertension, and renal failure. Identification of the new markers in relation to acute pyelonephritis (APN) and its treatment is essential for designing interventions that would minimize tissue damage. This prospective study investigated the first UTI infection in 71 children (age range: 1-24 months) in respect to interleukin-6 (IL-6) -174G/C polymorphism and renal scarring. The patients were divided into an APN group and a lower UTI group according to dimercaptosuccinic acid (DMSA). The IL-6 -174G/C genotypes were determined by tetra-primer ARMSPCR. Serum IL-6 was significantly higher in the APN group than in the group with lower UTI (p<0.05). In both groups, the -174G/C genotype and allele frequencies did not differ significantly from the control group. The highest white blood cell (WBC) count was observed in the CC genotype (p<0.05). A non-significant trend toward higher serum IL-6 was observed in children with CC genotype. On follow-up DMSA imaging performed 6 months later, renal scarring was detected in 36.9% of APN children. We did not find the significant association of IL-6 -174G/C polymorphism with APN and/or postinfectious renal scarring. These results indicate that serum IL-6 concentrations were significantly higher in children with APN than in patients with lower UTI.

Expression profiling of the AT2R mRNA in affected tissue from children with CAKUT

OBJECTIVES

Congenital anomalies of the kidney and urinary tract (CAKUT) are common causes of chronic renal failure in children. The angiotensin II receptor type 2 (AT2R) is one of proposed candidate genes for CAKUT, but the expression was never explored in humans. The aim was to establish the AT2R gene expression in human CAKUT concerning -1332A/G polymorphism, which might affect alternative splicing.

DESIGN AND METHODS

Forty-eight patients with CAKUT constitute the basis of this study. Genotyping for -1332A/G, RT-PCR for AT2R gene expression and confirmation sequencing were performed.

RESULTS

The expression of Ex 1/2/3 and Ex 1/3 transcript splice variants of the AT2R mRNA were detected in human CAKUT tissue. The pattern was observed independently of A to G transition.

CONCLUSIONS

The expression of AT2R mRNA in human CAKUT was established for the first time and was not affected by -1332A/G polymorphism in children with CAKUT.

Pulmonary inflammatory myofibroblastic tumor associated with nephrotic syndrome

Inflammatory myofibroblastic tumor (IMT) of the lung is a benign, non-metastasizing tumor with the possibility of local infiltration, recurrence or persistent local growth. This kind of tumor arises due to an unregulated growth of inflammatory cells. To our knowledge, IMT associated with nephrotic syndrome has not yet been recognized. Therefore, we present the case of a 14-year-old girl with lung IMT associated with secondary nephrotic syndrome (NS), which was cured after tumor removal.

Infantile polyarteritis nodosa presenting as hyponatraemic hypertensive syndrome

The association of arterial hypertension with hyponatraemic dehydration, known as hyponatraemic hypertensive syndrome (HHS), is a rare and serious hypertensive complication. Here, we describe a 17-mo-old girl who presented with severe hyponatraemic dehydration, hypokalaemia, polyuria, and nephrotic-range proteinuria associated with malignant arterial hypertension and systemic inflammatory disease. Diagnosis of classic polyarteritis nodosa (c-PAN) was made on the basis of renal arteriography demonstrating small arterial aneurysms in association with non-aneurismal changes such as arterial cut-off, arterial tapering stenosis and nephrogram perfusion defect. A decrease of blood pressure by antihypertensive treatment resulted in the normalization of HHS abnormalities. However, c-PAN became well controlled only after 4 mo of immunosuppressive therapy.

CONCLUSION

The main interest of this case was the uncommon presentation of systemic polyarteritis nodosa in a very young child. Renal ischaemia from intrarenal vessel disease may have been the trigger event for HHS in our case. Management of PAN-associated severe arterial hypertension is based on immunosuppressive and antihypertensive treatment.

Casual and ambulatory blood pressure monitoring in children with renal scarring

INTRODUCTION Renal scarring is the most common cause of arterial hypertension in children. High blood pressure (BP) and microalbuminuria contribute to the progression of chronic renal disease. OBJECTIVE The aims of the study were: to assess BP in children with renal scarring by continuous ambulatory blood pressure measurement (ABPM) in comparison to the casual method (CBP), and to determine the correlation between ambulatory blood pressure (ABP) and/or casual blood pressure (CBP) values and proteinuria in children with renal scarring. METHOD This forward-looking study comprised thirty-five children (26 girls and 9 boys), aged between 3-13 years, 10.4?3.9, X+SD. Blood pressure was measured using the casual method (CBP) with a mercury manometer; BP was measured three times and the average was taken as a referent value. ABPM was performed using the oscillometric method with the Space Labs device, model 90207. RESULTS 45.71% of patients were classified as hypertensive by ABPM, while only 22.6% of CBP measurements were above the 95th percentile (p<0.01). "White coat hypertension" was present in 40% of the patients. Non-dipping BP alteration was detected in 37.14% of the patients. CONCLUSION Nocturnal systolic hypertension (systolic non-dipping alteration) is very frequent in children with renal scarring. Nocturnal diastolic blood pressure, detectable only via ABPM, is positively correlated with proteinuria and may be an initial sign of the progression of renal scarring. ABPM is more sensitive than CBP in the evaluation of BP in children with renal scarring.

[The benefit of plasmapheresis in a patient with steroid-resistant nephrotic syndrome and anuria--long-term follow-up]

Recently, plasma exchange (PE) has been added to the treatment regimen for patients with steroid-, cyclophosphamide-, and cyclosporine-resistant nephrotic syndrome. This is a case report of a female patient with severe acute renal failure (ARF) during the relapse of steroid-resistant nephrotic syndrome (SRNS) who recovered completely after PE and became steroid-sensitive in further follow-up of 48 months. An 8-year-old girl was referred to Nephrology Department of the University Children's Hospital due to relapse of SRNS complicated with ARF. Her nephrotic syndrome (mesangioproliferative glomerulonephritis) was diagnosed at the age of 17 months. During the following 6 years, she was given several therapeutic regimens including pulse prednisolone, cyclophosphamide, Cyclosporine (CyA), but she continued to have frequent relapses and during the last six months she was steroid- and cyclosporine-resistant. Three days before admission, she was febrile, had cellulites of the lower abdominal wall, diarrhea, vomiting, hypovolemic shock with generalized edema, severe hypoproteinemia and hypoalbuminemia. In a local hospital, she was treated with fresh frozen plasma, albumin, methylprednisolone, furosemide and antibiotics, but she became anuric and was referred to our hospital. There were no signs of hemolysis. Anuria lasted for 12 days. She was discharged after 42 days in remission with normal GFR. Principal treatment included: 13 sequential hemodialysis sessions (30% of body weight was removed as excess volume), 6 PE, corticosteroids, CyA, ACE inhibitor, antibiotics, antimycotics, and cimetidine. Six PE sessions were performed every other day. In further 48-month follow-up, while under the treatment of CyA the patient had a few steroid-sensitive relapses, the first being 6 months after PE. The second kidney biopsy showed focal segmental glomerulosclerosis with no signs of apparent CyA nephrotoxicity. "Malignant" course of disease in our patient was a good reason to introduce PE into the treatment. Since PE was the only additional mode of treatment, it is believed that its effect was crucial for milder activity of the disease.

ACE and AT1 receptor gene polymorphisms and renal scarring in urinary bladder dysfunction

The objective of this study was to investigate whether DNA polymorphisms of the renin-angiotensin system (RAS) genes were associated with renal scar formation in pediatric patients with bladder dysfunction (BD). Although these children are born healthy, due to persistence of immature voiding habits and evolution of BD, some develop progressive renal damage. It has been suggested that the DD genotype of the angiotensin I-converting enzyme (ACE) gene might be an adverse renal prognostic factor. The insertion/deletion (I/D) polymorphism of the ACE gene and the A1166C polymorphism of the angiotensin II type 1 receptor (ATR1) gene were identified by polymerase chain reaction amplification in 42 children with BD (aged 5-14 years) and 198 healthy adult controls. Twelve children had urgency syndrome and 30 had dysfunctional voiding. Renal scarring was found in 16 patients, while 26 patients had normal kidneys on dimercaptosuccinic acid scan. In children with renal lesions there was significant over-representation of the DD genotype compared with either controls or patients without renal damage ( P<0.05). On multivariate analysis, the DD genotype was the only factor that had a significant impact on renal scar formation, introducing a 2.51-fold risk (odds ratio 2.51, 95% confidence interval 1.04-6.04, P=0.04). The A1166C gene polymorphism was not significantly associated with the development of parenchymal damage in children with BD. Our findings introduce ACE I/D gene polymorphism as an independent risk factor for parenchymal destruction in pediatric patients with BD.

[Renovascular hypertension in a child with type 1 neurofibromatosis]

Arterial hypertension in pediatric patients with neurofibromatosis type 1 (NF 1) is usually due to renal artery stenosis (RAS) mainly involving the proximal part of the vessel. The treatment modalities are highly individualized. In severe and/or bilateral RAS, antihypertensive drugs are either ineffective or have the potential risk for acute renal failure, while percutaneous transluminal angioplasty (PTA) has limited success due to the ostial localization of RAS and the tough fibrotic tissue involved that is refractory to dilatation Renal autotransplantation has potential advantages when medical control and PTA/or bypass techniques failed. Here we report 5 year-old girl with NF 1 and hyponatremic hypertensive syndrome due to severe bilateral disease, occluded proximal part of the right artery and ostial stenosis (80%) of the left one. Only left kidney was identified on 99 m Tc DTPA, but the right one was visualized on the renal ultrasonography and in the late phase of arterial renography due to well developed collateral circulation. Multiple antihypertensive drugs (nifedipine, labetolol and minoxidil) in maximal doses and PTA failed to normalize BP while short term therapy with ACEI with NF1 and hyponatremic hypertensive syndrome due to severe bilateral renovascular disease; occluded proximal part of the right renal artery and ostial stenosis (80%) of the left one. Only left kidney was identified on 99 m Tc DTPA, but the right one was visualized on the renal ultrasonography and in the late phase of arterial renography due to well developed collateral circulation. Multiple antiphypertensive drugs (nifedipine, labetolol and minoxidil) in maximal doses and PTA failed to normalize BP while. short term therapy with ACEI, captopril induced transient acute renal failure. Autotransplantation of right kidney saved its function and improved BP control. Our current case Autotransplantation of right kidney saved its function and improved BP control. Our current case is illustrative for a difficult management of renovascular hypertension in children with NF1. This is the first and up to now the only case of autotransplantation performed in Yugoslavia.

[Continuous ambulatory monitoring of blood pressure and the left ventricular mass index in children with kidney diseases]

INTRODUCTION

Numerous epidemiological studies have shown that blood pressure (BP) is positively related to cardiovascular morbidity and mortality. Although the relationship between BP and the incidence of morbid events is consistent and highly significant, it is difficult to predict the absolute risk. Several studies have shown that the organ damage associated with hypertension correlate to a greater degree with 24 h average BP than with clinic BP and the most of them evaluated left ventricular hypertrophy in these patients.

OBJECTIVE

To evaluate the correlation between left ventricular mass index (LVMi) and BP, BP variability, pulse pressure (PP), BP load and hyperbaric index (HBI).

DESIGN AND METHODS

Ambulatory blood pressure monitoring (ABPM) was performed in 30 children with renal disease aged 12.7 +/- 5.5 years. Ten of them had normal renal function, 3 had renal transplant and 17 of them had end-stage renal disease and were on chronic haemodialysis. All of the patients were submitted to an echocardiographic evaluation and LVMi was calculated according to Penn convention. Ambulatory blood pressure monitoring was performed during the 24 h period and average values of systolic and diastolic BP were evaluated. As an index of variability of BP values we used standard deviation (SD) of mean. Evaluation of average BP values has some disadvantages--it does not take into account the peaks of blood pressure and the values are lower if the circadian rhythm of BP is preserved--for this reason BP load and HBI were evaluated as well. BP load represented the percentage of BPs exceeding the upper limits of normal and HBI the integrated area under the ambulatory BP curve. For the upper limits of normal was used 95th percentile from the multicenter study of German authors.

RESULTS

There was no correlation between LVMi and evaluated parameters.

CONCLUSIONS

The response of myocardium to chronic increase of the afterload is highly individual, and probably the role of genetics in this is very important. Echocardiography (LVMi) could not be used with certainty for the evaluation of ventricular mass.

[Evaluation of representative blood pressure measurement in children on hemodialysis]

The diagnosis of hypertension in patients on chronic haemodialysis is not easy because the blood pressure changes as a consequence of therapy (haemodialysis) and attenuated circadian rhythm of blood pressure is often present. The estimation of representative blood pressure levels is difficult because it is not known whether blood pressures measured before starting or after completion of haemodialysis are predictive for the average interdialytic blood pressure. Our group of patients consisted of 18 children with endstage renal failure, aged 13.5 +/- 3.2 years, treated with chronic haemodialysis from 0.1 to 110 (mean 25.8, median 19) months. Ambulatory blood pressure monitoring was performed during 44 h interdialytic period. Blood pressure was also measured with sphygmomanometer before starting and after completion of heamodialysis. The average blood pressure values for the last ten haemodialyses were evaluated as well. Multiregression analysis showed significant correlation between interdialytic blood pressure (systolic and diastolic) and blood pressures measured before haemodialysis (r = 0.74; p < 0.001, r = 0.78; p < 0.001, respectively) and after haemodialysis (r = 0.76; p < 0.01, r = 0.6; p < 0.05, respectively). Statistically high correlation between these blood pressures was also confirmed for the average blood pressure values for the last 10 haemodialyses (r = 0.78; p < 0.001, r = 0.75; p < 0.001 and r = 0.78; p < 0.001, r = 0.86; p < 0.001, respectively). Our findings show that blood pressures measured before starting or after completion of haemodialysis give good information about interdialytic blood pressure in children on chronic haemodialysis.

[The Lesch-Nyhan syndrome]

Deficiency of hypoxanthine phosphoribosyltransferase (HPRT) has a broad spectrum of clinical manifestations, from the complete enzyme defect, the Lesch-Nyhan syndrome with severe neurological deficiency to the partial defect associated only with uric acid overproduction and its consequences. We present a 5-year old boy with Lesch-Nyhan syndrome. He came to our hospital because of abdominal pain, vomiting and gross haematuria. At the age of 8 months he was categorized as a "cerebral palsy" patient due to involuntary movements and high degree of spastically and tonic spasms. He remained incapable of sitting or standing alone. The patient's brother and two uncles were also categorized as "cerebral palsy" cases and died at the age of 8-14 years. Clinical examination revealed hyperuricaemia and hyperuricosuria, radiolucent renal and urinary bladder stones. HPRT enzyme activity was totally absent, while adenine phosphoribosyl transferase activity was increased compared to control. The patient was treated with allopurinol, urinary alkalization, low-purine diet and adequate hydration while he was in hospital. However, his parents refused further treatment and follow-up. The most important issue is whether the healthy sisters of the patients are heterozygotes for HPRT deficiency. This DNA analysis is now in progress.

Hyponatremic hypertensive syndrome

We report on a 4-year-old girl with hyponatremic-hypertensive syndrome (HHS), a rare entity in childhood. The girl was referred to us from a local hospital with a history of recurrent fever, vomiting, and seizures. On admission she was markedly dehydrated. Initial investigations revealed severe hyponatremia (serum Na 120 mmol/l), hypochloremia (serum Cl 68 mmol/l), and mild hypokalemia (serum K 3.3 mmol/l), while serum calcium and magnesium were normal. Serum urea was 5 mmol/l and serum creatinine was 62 mumol/l. Despite hyponatremic dehydration, her urine output was high (2050 ml/24 h), as was her urinary sodium (168 mmol/24 h). She had massive transient proteinuria (maximal 1642 mg/24 h) while being severely hypertensive (blood pressure 210/160 mmHg). Further investigations revealed right kidney scarring, hyper-reflexive bladder dysfunction, massive brain infarcts, and myocardial left ventricular hypertrophy. Renal arteries were normal on arteriography. Blood pressure control resulted in normalization of serum and urinary electrolytes and decrease of proteinuria. Hyponatremia and transient massive proteinuria in this patient seem to be caused by high-pressure-forced diuresis due to malignant renoparenchymal hypertension.

[20 years' experience in the treatment of children with terminal renal insufficiency in Yugoslavia]

The first specialized haemodialysis (HD) paediatric centre in former Yugoslavia was established at the University Children's Hospital in Belgrade in January 1980. A total of 194 children (F: 98, M: 96), aged less than 19 years (10.12 +/- 4.23), were treated for renal replacement therapy (RRT) over 20 years. Average annual incidence rate was 1.59 per million of child population (pmcp) aged less than 19 years for the period 1980-1990 (former Yugoslavia) and 2.85 pmcp aged less than 19 years for the period 1990-2000 (present Yugoslavia). Reflux nephropathy was the most frequent underlying disease and accounted for 37.06% of total cases, while other primary renal diseases were: glomerulonephritis (GN) 17.26%, cystic/hereditary familial nephropathy 12.69%, congenital disease 11.68%, interstitial nephritis 5.58%, non-recovered tubular necrosis 3.55%, secondary GN 1.52% and 10.66% remained with doubtful diagnosis. HD was the first RRT in 84.02%, peritoneal dialysis (PD) in 14.43% and pre-emptive transplantation in 1.55% of all patients. A total of 53 patients (27.3% of total terminal renal failure (TRF) patients) received 56 kidney transplants (58.93% live related, 37.50% cadaveric, 3.57% live-non related). Actual survival in RRT was 64.53% 5 in years; 51.68% in 10 and 48.23% in 15 years. Patient survival in HD was significantly better over the last ten-year period than in the first ten-year period (35.88% vs. 75.75%; p < 0.005) as well as the survival of transplanted patients in the same two periods (67.62% vs. 95.45%). Graft survival was 79.85% in 5 and 70.50% in 10 years. Cardiovascular complications were the most common cause of death of patients on RRT (56.10 posto) followed by infection (24.39). On December 31, 1999, 54 patients on RRT were alive less than 19 years: 75.92% in HD; 22.22% with functioning graft and 1.85% on automatic PD. This is the first national-wide long-term study of incidence and aetiology of paediatric TRF and outcome of paediatric RRT in Yugoslavia.

[The captopril test--an aid in the detection of scarring nephropathy as a cause of arterial hypertension in children]

Renal scarring with and without vesicoureteral reflux (VUR) has been now recognized as an important cause of paediatric hypertension for many years [1-5]. However, its pathogenesis has still remained uncleared. The widespread concept implicated the activation of renin-angiotensin system finding a powerfull support in higher peripheral plasma renin activity (PRA) in children with reflux nephropathy than in controls [6, 7] and in beneficial antihypertensive effects of ACE inhibitors. The latter, in form of captopril, has also been used in captopril test and in renal scintigraphy and isotope renography following the administration of captopril to provide evidence for renin dependent hypertension [8, 9]. Published studies of captopril test have centred on the identification of renovascular as opposed to essential hypertension [10-18, 20-22]. The aim of our study was to assess the usefulness of captopril test in differentiation between hypertensive children with renal scarring from those with essential hypertension. We studied blood pressure (BP) and PRA responses to a single dose of captopril in two groups of hypertensive children. Group A consisted of 29 patients, 14 boys and 15 girls, who had renal scaring as demonstrated by renal 99mTc dimercaptosuccinid acid scan (99m Tc DMSA) and/or intravenous pyelography. Group B included 19 patients, 19 boys and 10 girls who had arterial hypertension, while clinical examination excluded renal and other definable causes of BP elevation, and they were therefore considered to have essential hypertension. At the time of the study all patients had normal glomerular filtration rate and were not salt depleted. They did not receive any antihypertensive medication for at least two weeks. The test was performed in the morning in fasting sitting patients. At the start of the test a small vein in the hand or forearm was cannulated to permit blood sampling. BP was measured 10, 20, and 30 minutes before captopril administration to get baseline BP (mean of these three measurements) and to allow the children to become accustomed to the test procedure. A single oral dose of captopril 0.64 +/- 0.04 mg/kg body weight was given to patients from group A and almost the same dose of captopril, 0.63 +/- 0.05 mg/kg body weight, to patients from group B. The patients remained sitting and BP was measured every 15 minutes during an hour. Blood for PRA was drown in the sitting position (17 patients from group A and 16 patients from group B) before and one hour after the dose of captopril. Samples of blood for basal PRA were collected from 16 patients from group A and in 14 patients from in B in lying position after waking up in the morning. PRA was measured by radioimmunoassay using a commercially available kit, SB-REN 2, from CIS Bio International. According to the criteria of Muller et al. [10] the captopril test was positive if the post-captopril PRA (ng/ml/h) was greater than or equal to 12 with an increase of greater than or equal to 10 and relative increase of greater than or equal to 15% (400% if initial PRA was < 3). The results of our study are presented in Tables 1 and 2 and in Graphs 1 and 2. The age of patients, doses of captopril, initial BP and PRA before the use of captopril did not much differ between studied groups. Fall of BP and PRA increase were highly significant (p < 0.001) both in group A and group B. However, the hypotensive reaction of diastolic BP and MAP were more pronounced in group A (14.45 +/- 1.67% and 15.81 +/- 1.62%) than in group B (6.95 +/- 2.21% and 8.96 +/- 1.75%; p < 0.01), but there were no significant differences in PRA and systolic BP changes and positive results of captopril test between the studied groups. Hypotensive responses of diastolic BP and MAP greater than 10% of initial values were found to be more frequent in group A (79.32% and 79.31%) than in group B (26.61% and 31.57 degrees %; p < 0.001 and p < 0.01). Diastolic BP and MAP were directly related to the dose of cap

[Renal tubular function in children with hypercalciuria]

INTRODUCTION

Renal stone disease is commonly due to hypercalciuria [1, 2], which may be assessed either from a 24-hour urinary collection or from the fasting first morning urine. Hypercalciuria during childhood has been defined by a 24-hour calcium excretion greater than 3.5 mg/kg per day and/or calcium to creatinine ratio greater than 0.20 [3]. The alteration in the calcium transporting systems plays a pathogenetic role in promoting hypercalciuria [4, 5]. Since calcium reabsorption along the nephron is intimately related to that of other electrolytes and substances, it can be hypothesized that patients with hypercalciuria may have other renal tubular defects. The aim of the study was to investigate proximal tubular function (tubular reabsorption of sodium, potassium, phosphate and glucose) and distal tubular function (urinary concentrating capacity and acidifying capacity) in children with hypercalciuria.

PATIENTS AND METHODS

Two groups of children were studied: hypercalciuric group included 23 children with hypercalciuria (10 males, aged 11.9 +/- 4.1 years), of whom 6 with nephrolithiasis, and control group included 42 healthy children (20 males, aged 11.2 +/- 3.8 years). All subjects had normal serum values for calcium, sodium, potassium, phosphate and glucose, as well as normal renal function. The urinary excretion of calcium, sodium, potassium, phosphate, glucose and creatinine was measured in a 24-hour urine specimen by standard laboratory methods. Urine osmolality and urinary specific gravity were measured following 12-hour water-deprivation test. A short ammonium chloride loading test was performed in 3 patients with urinary pH above 5.5. The fractional excretion of sodium, tubular phosphate reabsorption and renal threshold phosphate concentration were calculated according to standard formula. Statistical analysis was performed using the t-test and analysis of variance (ANOVA). Kruskal-Wallis method was used to compare urinary phosphate excretion between two groups.

RESULTS

Table 1 summarizes urinary excretion of electrolytes in children with hypercalciuria compared with healthy controls. We found that urinary sodium excretion was significantly increased in patients with hypercalciuria when compared with controls (p < 0.05). Urinary phosphate excretion was significantly higher in patients with hypercalciuria in comparison to controls, and this was accompanied by a significant lowering of the tubular phosphate reabsorptive threshold (p < 0.05). Urinary potassium excretion tended to be lower, although not significantly, in the hypercalciuric children than in normal subjects. Table 2 shows the mean values +/- standard deviation of urinary specific gravity, urinary osmolality and urinary pH. Urinary specific gravity mean value was significantly lower in patients with hypercalciuria in comparison to controls (p < 0.05). Urinary pH was found below 5.5 in all patients. Glycosuria was detected in 3 patients (13.3%). As shown in Graph. 1, a significant correlation between the urinary excretion of calcium and sodium was demonstrated in both groups of children (r = 0.29; p < 0.01).

DISCUSSION

The present study shows that children with hypercalciuria have significantly higher urinary sodium and urinary phosphate excretion in comparison to controls, while urinary potassium excretion is normal in both groups of children. According to some recent reports [6-9], these findings may indicated defects of the renal tubular transport of sodium and phosphate which may be interpreted as a cause or a consequence of the alteration of the calcium transporting system. Defects in both proximal and distal renal tubular functions have been demonstrated in patients with nephrolithiasis, particularly those with hypercalciuria. Proximal renal tubular defects include defects in sodium, fluid, phosphate and glucose reabsorption, which were evident also in our patients. (ABSTRACT TRUNCATED)

[Continuous ambulatory measurement of blood pressure in children--personal experience]

Ambulatory blood pressure monitoring (ABPM) during normal daily activities and during night, when the patient is asleep, is a new method of measuring blood pressure (BP) in children, used for better diagnosis and treatment of hypertension. Compared to casual BP measurements, it documents normal daily BP variations, BP during sleep, the influence of emotional and physical stress on BP and is a better predictor of hypertension associated with end-organ damage. However, the experience in ABPM in children is still limited. In our country ABPM has been used since recently, and first results are referred to children with end-stage renal failure.

SUBJECTS AND METHODS

ABPM was performed in two groups of children: group A consisted of 61 children, aged 14.3 +/- 2.9 (mean +/- SD) yrs in whom intermittent outpatient BP measurements (for at least 3 months) suggested the diagnosis of hypertension (according to the data of Second Task Force); group B consisted of 52 patients (pts), aged 12.8 +/- 4.6 yr with renal disease. Four pts from group A (6.6%) and 20 pts from group B (38.5%) received antihypertensive therapy (captopril, nifedipine, furosemide and propranolol ). All children from group A and half of the children from group B had normal renal function. Eighteen pts from group B were on chronic haemodialysis (34.6%). Blood pressure was recorded during a 24-hour period except in haemodialyzed pts (48 h) (Table 1). Results of BP measurements are presented as the mean values of BP during a 24-hour period, during normal daily activities and during sleep. We used the age- and gender-appropriate 95th percentile from the Task Force Study as the daytime upper-limit of normal and 10% lower for the upper-limit at night. According to BP load (the percentage of BPs exceeding the upper limits of normal for age), children were assumed to have mild-to-moderate hypertension (BP load between 20% and 40%) or severe hypertension (BP load more than 40%). The success of antihypertensive therapy was evaluated after 1-3 months in 11 pts (twice in 10 pts and three times in one pt).

RESULTS

In group A 39.4% of pts were normotensive and 36.1% were without antihypertensive therapy, 58.4% of normotensive and 40.5% of hypertensive pts had blunted circadian BP rhythm (nocturnal BP reduction of less than 10% of diurnal values) (Graph. 1). In group B 38.5% of pts were normotensive and 27% were without antihypertensive therapy. In the group of normotensive pts alteration of circadian BP rhythm was found in 40% of pts with normal renal function, 80% of pts with chronic renal failure and in 100% of pts with terminal renal failure, while in the hypertensive group, altered circadian BP rhythm had 68%, 100% and 92% of pts, respectively (Graph 2). Mild-to-moderate hypertension had 54% of hypertensive pts from group A and 37.5% of hypertensive pts from group B. Severe hypertension was more frequent in group B (62.5%) comparing to group A (46%). The effectiveness of antihypertensive therapy was assessed in 11 pts. In 69.2% of pts BP became normal or was significantly decreased, in 23.1% of pts BP was not changed and 7.7% of pts had higher values of BP.

DISCUSSION

ABPM is very useful for diagnosing white coat hypertension. Like other authors, we have pointed out that more than one third of pts who were hypertensive according to usual BP measurements had normal 24-hour BP and we classified them as white coat hypertensives. More than a half of the pts had blunted circadian BP rhythm, and as it is not certain whether they will become hypertensive in adulthood they should be periodically controlled. There are several proofs that results of ABPM have a better correlation with hypertensive end-organ damage; therefore ABPM is used for assessing the severity of hypertension. In our former work, we showed excellent correlation of BP with left ventricular mass index in children with end-stage renal failure. (ABSTRACT TRUNCATED)

[Serum osteocalcin in children with chronic renal insufficiency]

The research of the bone metabolism has undergone a long evolution which began with the use of radioisotopes in calcium kinetic studies and went through the determination of several humoral parameters like alkaline phosphatase (ALP), hydroxyproline and intact immunoreactive parathyroid hormone (iPTH) and finally to the assay of a new serum and urinary parameters of bone metabolism, like osteocalcine (OC) and procollagen and collagen metabolites. The X-ray study of the skeleton, densitometric techniques, computerized tomography, scintigraphy and NMR are used for visualization of bone changes, but bone biopsy and histomorphometry provide the most precise evaluation [1]. Disorders of bone and mineral metabolism in children with chronic renal failure (CRF) are an almost regular occurrence; so early discovery and treatment of these changes are very important [2]. The aim of this study was to measure the serum OC level in children with CRF and terminal renal failure (TRF), treated with chronic haemodialysis, and to evaluate the significance of OC compared to other humoral parameters of renal osteodistrophy, such as ALP and iPTH.

MATERIALS AND METHODS

We studied the fasting levels of OC in three different groups of children: group A consisted of 18 patients with TRF; group B consisted of 12 patients at different stages of CRF, and group C consisted of 32 healthy children, all of the approximately same age. Clinical characteristics of the examinded children are presented in Table 1. Of 30 patients, 26 were treated with calcium carbonate and 21 with vitamin D analogues. None were treated with aluminium hydroxide. Additional parameters included serum calcium, phosphate, ALP and body height, while serum concentrations of iPTH and ionized serum calcium were measured only in group A. Serum OC was measured by radioimmunoassay using OSTK PR RIA (CIS), while ELISA-PTH (CIS) radioimmunoassay was used to determine iPTH plasma levels. Statistical analyses were performed using Kolmogorov-Smirnov test to confirm normal distribution, the Pearson and Spearman rank sum test for correlation between variables of interest, while analysis of variance was used to compare the findings.

RESULTS

Serum OC levels were significantly different in all groups (p < 0.01); they were three times higher in group A than in group C. Similar increase was noticed in plasma iPTH, assuming that "normal" uremic iPTH was raised up to threefold above normal range (between 10 and 60 pg/ml) [2]. However, the total serum ALP activity was not sensitive as OC and iPTH, since ALP increases were less as compared to them. OC was age related only in group A (p < 0.01), with a positive correlation between OC and duration of haemodialysis (p < 0.05), as well as between OC and serum phosphate (p < 0.05), but there was no correlation between OC and growth retardation (expressed by SDS), bone age and current therapy for renal osteodistrophy. A direct correlation between OC and ALP was found only in healthy children (p < 0.01), while in groups A and B it was remarkable, although not statistically significant (p = 0.08) (Graphs 1, 2, 3). In group A, ALP and iPTH were directly correlated (p < 0.001), but the correlation of OC with iPTH was less significant (p = 0.06). In patients with CRF no correlation was found between glomerular filtration rate and OC.

DISCUSSION

OC is a bone-derived noncollagenous protein of low molecular weight (about 5800 D), containing residues of the vitamin K dependent amino acid gamma-carboxyglutamic acid and is synthesized by osteoblasts and odontoblasts. Calcitriol is a potent stimulator of OC synthesis, acting at the transcriptional level and increasing mRNA severalfold. OC is found mainly in bone, but nanomolar concentrations circulate in the blood. Its serum levels are an expression of the bone formation process and are age related (higher in the neonatal and adolescent period). ABSTRACT TRUNCATED.

Endothelin-1 in acute renal failure

To study the pathological significance of circulating endothelin (ET) in ARF, we measured plasma ET in seven children (mean age 8.8 +/- 4.4 years) with ARF in the most severe phase and 3.7 +/- 3.5 months later in the recovery period. Twenty-seven healthy children were included in the study as controls. Plasma ET level was measured by highly sensitive and specific radioimmunoassay for ET-1 and ET-2 (ET-1/2, Biomedica, Vienna). Plasma ET was significantly higher in the most severe phase of ARF (4.75 +/- 4.08 fM/ml) than in the recovery period (0.78 +/- 0.24 fM/ml; p < 0.01), but comparing to plasma ET in the healthy children, the difference was only of borderline statistical significance (Pf, 0.0573). Since plasma concentrations of creatinine did not correlate with plasma ET in patients, either in acute or in the recovery phase of disease, we concluded that decreased GFR is not the main factor determining an increased ET in ARF. We suggest that elevated plasma ET in ARF may be secondary to vascular endothelial dysfunction and speculate that enhancement synthesis of endothelial relaxing factor (EDRF) inhibits ET synthesis during the recovery period. We did not find any relationship between plasma ET and blood pressure (BP) in patients with ARF, so we conclude that circulating ET is not the main factor determining BP in ARF.

[Kidney transplantation in children]

During the last 14 years, since the opening of the Center for Childrens' Hemodialysis the University Children's Hospital of Belgrade, 174 children with terminal renal failure were treated by chronic hemodialysis. Of these, only 35 patients (20.1%), 14 girls and 21 boys, mean age 12.6 +/- 4.9 years, were transplanted. The average waiting time for transplantation was 24.6 months (range 0-120 months). Twenty-five patients were transplanted with paternal kidney, the others were cadaveric transplantations. More than half of transplantations were done abroad. Of 35 patients, 20 were under follow-up for over 6 months (45.7 +/- 7.2 range 6 to 102 months). Five year patient survival was 94.1% and the graft survival over the same period was 76.4%. 45.7 +/- 7.2 months after transplantation the outcome was the following: 11 patients (55%) had GFR over 60 ml/min/1.73 m2, 5 patients (25%) had GFR from 25 to 60 ml/min/1.73 m2, 2 patients (10%) returned to chronic hemodialysis, 1 patient was retransplanted and 1 patient died. All patients with GFR of over 60 ml/min/1.73 m2 are well psychosocially rehabilitated, 62.4% are normotensive without antihypertensive therapy, and only 9.9% are growth retarded.

[Cystic tumefaction in the minor pelvis--the agenesis-dysplasia syndrome (case report)]

Ectopic kidney often shows signs of parenchyma maldifferentiation. Multicystic or dysplastic kidney is usually associated with congenital urogenital and skeletal system anomalies. In the Unilateral form of the agenesia-dysplasis syndrome, the kidney, if it is present, is small dysplastic and usually cystically changed. Ipsilateral uterus horn or vaginal agenesia are the most frequently associated anomalies. Case report. A six years old girl was clinically examined due to recurrent urinary tract infections. On ultrasound, the left kidney was enlarged, while the right kidney was absent in normal position. Cystic mass 4x5 cm was seen in the pelvis. The right kidney was not seen on IVP. CT scan showed a cystic formation in the pelvis, described as cystically changed dysplastic kidney. Pelviceal mass was extirpated. Exploration of the genital system revealed vaginal arch blinded in the hypoplastic right uterus horn. On pathohystology tumefaction corresponded to the dysplastic kidney.

IN CONCLUSION

unilateral renal aplasia or dysplasia may indicate genital anomalies having in mind the hereditary character of unilateral form of the agenesia-dysplasia syndrome therefore, it could be helpful in prenatal diagnosis of cystic pelvic mass of fetus in families with this syndrome.