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D Benini

Publications and source records attributed to D Benini.

12 recordsLinked to original sources

Megaureter: classification, pathophysiology, and management.

The term megaureter does not define a specific pathological condition, because it can be due to different underlying abnormalities. The most used classification includes three groups: refluxing megaureter, associated with vesicoureteral reflux (VUR); obstructive megaureter, associated with urine flow impairment at the vesicoureteral junction; non-refluxing non-obstructive megaureter, if neither obstruction nor reflux can be identified. Each group can be divided into two subgroups: primary megaureter; secondary megaureter. With the advent of antenatal ultrasound an increased number of cases are identified prior to the onset of symptoms. The common used investigation are: urinary tract ultrasound, voiding cystourethrography, urography, serial diuretic renography and pressure-perfusion studies (Whitaker test). The advent of prenatal and neonatal echography has modified the natural history of megaureter. Nowadays non operative management is preferred. Operative intervention is indicated only in these cases: significant impairment to urine flow; worsening renal function during the observation time; recurrent UTI in spite of adequate antibiotic prophylaxis.

Child↗

46, XY, del (3) (pter-->p25) syndrome: further delineation of the clinical phenotype.

A boy with monosomy for the distal part of the short arm of chromosome 3 is described. The clinical features this patient has in common with the previously reported cases include pre- and post-natal growth delay, microcephaly, craniofacial dysmorphism and mental retardation. In addition, minor abnormalities not previously reported were observed, such as snapping thumbs, dorsiflected big toes, connecting anterior and posterior fontanelles at birth, nasolacrimal duct stenosis and double urethral meatus. Conclusion These five new clinical findings may help in further delineation of the syndrome and allow its early recognition. A complete revision of clinical findings published in literature is reported.

Abnormalities, Multiple↗

Renal tolerability of teicoplanin in a case of neonatal overdose.

The literature does not contain reports regarding teicoplanin overdose in newborns. In a neonate with a history of recent postasphyctic acute renal failure which recovered within 7 days of life, antibiotic therapy with teicoplanin was started for sepsis due to Staphylococcus hominis. However, for 5 days the dosage was excessive (20 mg/kg twice daily instead of an initial dose of 16 mg/kg and then doses of 8 mg/kg once daily). Once this error had been noted, therapy was immediately suspended. Clinically the newborn had improved and blood culture at the end of the therapy was negative. Biohumoral tests revealed constantly normal levels of serum creatinine, serum cystatin C and blood nitrogen. Urinary parameters of tubulotoxicity were also within normal values. Urinary epidermal growth factor was increased. Teicoplanin was well tolerated at the renal level in the newborn even in this case of excessive dosage.

Acute Kidney Injury↗

Urinary epidermal growth factor in different renal conditions in children.

Several studies have demonstrated the important role of growth factors, particularly epidermal growth factor (EGF) and transforming growth factor alpha (TGFalpha), in cellular growth after renal damage. EGF is mainly synthesized by the kidney. Many studies indicate that urinary EGF concentration significantly decreases in patients with acute and chronic renal failure. In this study we determined urinary EGF concentrations in children with renal and/or urological pathologies. We investigated 38 patients, 17 males and 21 females, of 3.34+/-2.96 years (mean +/- standard deviation), who were followed in the Nephrologic Unit of the Pediatric Department of the University of Verona for recurrent urinary tract infections: seven of these had vesicoureteric reflux and 4 had hypodysplasia. The results were compared with those from a healthy age-matched group of 44 children. In all patients, we assessed renal function including an examination of the urine with a microbiological evaluation. Moreover, a renal ultrasound and a voiding cystourethrogram were performed.

Case-Control Studies↗

[Renal calculosis in pediatrics].

Urinary stones (calculi) are not a rare problem in pediatrics, presenting a prevalence of 1 case/20,000 children/year. Both nephrocalcinosis (deposition of calculi within the renal parenchyma) and urolithiasis (stone formation in the calyces, renal pelvis and bladder) may occur. Etiology of urinary stones involves metabolic, infectious, anatomic and idiopathic causes. Diagnosis and treatment require knowledge of a wide range of diseases. After urinary stones have been suspected, biohumoral tests and ultrasound examination should be routinely performed.

Acidosis, Renal Tubular↗

[Acquired methemoglobinemia: a case report].

When an infant presents severe cyanosis which is not associated with respiratory distress, methaemoglobinemia should always be suspected. In children its main inducers are contaminated water or vegetable broths with high nitrate levels (especially spinach and carrots) used to prepare powdered formula or soups. Children affected with methaemoglobinemia have a peculiar lavender colour. Blood from the heel sticks is chocolate-brown and does not become pink when exposed to room air. Diagnosis can be confirmed by excluding other causes of cyanosis and by spectrophotometric analysis of blood for methaemoglobin. When methaemoglobin's levels reach 60% or more, the patient will collapse and become comatose and may die. Therapy with methylene blue results in prompt relief. In this article we report a case of methaemoglobinemia due to the administration of powdered formula mixed with vegetable broths to a newborn aged 16 days. Furthermore we will present a short review of literature regarding methaemoglobinemia caused by toxic agents over the last 10 years.

Enzyme Inhibitors↗

[Hematuria in pediatric clinical practice].

Haematuria, which was known at the time of Hippocrates, is defined as the presence of an anomalous number of red globules in the urine. It may present itself in a macroscopic or microscopic form. The latter is frequently found and is present in 1-2% of children. The pathogenesis of haematuria has been the object of recent acquisitions. The diagnosis is based in the first instance on the association of a positive urinary stick and confirmation of the presence of red globules in an assay of the sediment. The study of erythrocytic morphology is still the most useful test to identify the site of bleeding, even if more recently other markers, such as an excessive presence of acanthocytes or reduced mean corpuscle volume, together with the traditional study of cylindruria may represent elements to differentiate between glomerular and non-glomerular haematuria. Both family and personal medical history as well as objective examination play an important role in the definition of haematuria. Abdominal ultrasonography and biohumoral tests may, in association with the earlier data, allow a rapid and correct diagnosis of children with haematuria. A more detailed diagnosis using biopsy should be taken into consideration in selected cases, for example in familial forms that are not clearly defined and forms associated with altered renal function tests, as well as in persistent microhaematuria lasting for more than one year.

Age Factors↗

[Nutrition in chronic renal insufficiency in the first year of life].

In the first year of life, period of maximal anabolism, optimal metabolic and nutritional conditions are strictly required. In fact growth retardation of the infant is seldom recoverable in the following pediatric ages. Conservative management of chronic renal failure in the first year of life is essentially dietetic. Normal growth is warranted by adequate protein intake (6-8% of total calories) and optimal caloric support (> 75-80% of RDA). Water requirements (evaluated on the basis of diuresis, hydratation and weight variations) must be administrated during the whole 24-hours period to avoid dehydration. Sodium and potassium limitations are not generally indicated and only in advanced phases must be carefully evaluated. On the contrary, in early stages, a reduction of phosphorus intake and calcium and vitamin D supplementation are commonly suggested. Maternal milk is the nutritional gold standard during the first year of life. Hyposmolar formula with normal Na and low P content (Ca/P ratio = 1.4-2) and a protein content comprised between 1.4 and 1.8 g/100 ml represent the second choice.

Calcium↗

[Glycopeptides and the newborn infant's kidney].

The aim of this paper was to evaluate glycopeptide nephrotoxicity in the newborn. The exact mechanism of nephrotoxicity has not been defined. Basal mechanism of vancomycin nephrotoxicity seems related to the energy-dependent tubular transport of the drug from blood to tubular cell across the basolateral membrane. Moreover a tubular reabsorption is probably involved, but it is not relevant for nephrotoxicity. Considering the widespread use of this antibiotic, the question of nephrotoxic side effects in humans is of great importance. However, the results of studies published to date are controversial. Results differ considerably depending on the period considered and on the sensitivity of the methods used to indicate renal damage. In paediatric patients (including neonates) the nephrotoxicity of vancomycin appears to be less than that in adults, thus confirming a number of experimental observations. It is commonly suggested that pharmacokinetic monitoring of doses in children should minimize nephrotoxicity. The most important risk factors for the development of the nephrotoxic action of vancomycin are: pre-dose values > 10 mg/l, prolonged therapy (> 21 days), and concomitant treatment with aminoglycosides. In most cases nephrotoxicity associated with vancomycin is reversible, even after high doses. In conclusion it could be speculated that vancomycin nephrotoxicity relates to the combined effect of a large area under the concentration-time curve and duration of therapy. Teicoplanin is a new glycopeptide that is effective in the treatment of both children and neonates and offers the advantages of once daily administration, choice of administration route (intramuscular or rapid intravenous bolus) and lack of requirement for routine therapeutic drug monitoring. Finally it seems less nephrotoxic than vancomycin. In the neonatal age bracket, none of the 173 patients treated presented abnormalities of traditional kidney function parameters.

Anti-Bacterial Agents↗

[Vesico-ureteral reflux in pediatrics].

Vesico-ureteral reflux (VUR) is the most frequent uropathy involving 1-2% of children. Genetics, familiarity, race gender and age intervene in the pathogenesis of VUR. In particular, neonatal VUR seems to represent a specific entity. Different factors determine a renal damage due to RVU: direct action of VUR (back pression), urinary tract infection (UTI), inflammatory mechanisms and renal dysplasia. Micturing cystourethrography and nuclear cystography are currently performed for the diagnosis of VUR, being ultrasound examination aspecific. Functional parameters are now investigated in association with new morphologic studies. The strict relationship of VUR and UTI is discussed. The treatment (medical, surgical) of VUR is not well established, although some guidelines can be suggested. Finally an adequate support must be given to the family for an optimal management.

Female↗