Biomedical subjects

C Pizzini

Publications and source records attributed to C Pizzini.

8 recordsLinked to original sources

PubMed2001

Multicystic dysplastic kidney and contralateral vesicoureteral reflux. Renal growth.

BACKGROUND: To evaluate if vesicoureteral reflux (VUR) contralateral to the multicystic dysplastic kidney can interfere with the compensatory renal hypertrophy. METHODS: Twenty-seven patients (17 males, 10 females) with multicystic dysplastic kidney (MDK) (14 on the right, 13 on the left) have been treated at the Nephrology Unit of the Pediatric Department of the University of Verona from birth up to the second year of life. All these patients were diagnosed as having MDK by prenatal ultrasonography. Seven children (4 males and 3 females) had VUR (5 monolateral, 2 bilateral), diagnosed at the end of the first month of life. After diagnosis children underwent antibiotic prophylaxis with beta-lactam compounds at low doses. Four patients underwent a surgical correction of VUR associated with nephrectomy within the second year of life. The remaining 3 patients were treated with antibiotic prophylaxis; a progressive resolution or downgrading of reflux grade took place respectively in 1 and in 2 of them. Only 6 children with MDK underwent nephrectomy. Renal growth was studied by serial echographic measurements of the longitudinal renal lenght (performed at birth, at 6 months, and at 2 years of life). RESULTS: Renal length was 5.68+/-1.24 cm, 6.72+/-0.88 cm, 8.56+/-1.27 cm in children without VUR, respectively at birth, 6 months and 2 years of life. Renal length was 4.65+/-0.63 cm, 6.70+/-0.64 cm, 7.07+/-1.14 cm in children with VUR, respectively at birth, 6 months and 2 years of life. A statistically significant difference was observed between the two groups at birth (p<0.05) and at 2 years of life (p<0.01). CONCLUSIONS: The conclusion is that VUR contralateral to the MDK is associated with small kidneys and reduced renal growth both at birth and at 2 years of life.

Age Factors↗

PubMed2000

C-reactive protein and serum amyloid A protein in neonatal infections.

In this study, we examine C-reactive protein (CRP) and serum amyloid protein A (SAA). Although the former is the best known and most commonly used indicator of inflammation, certain considerations underline the inadequacy of CRP determination alone for the early diagnosis of infection. In fact symptoms often precede the CRP elevation. SAA protein comprises a family of polymorphic apolipoproteins produced mainly by the liver, and several studies have stressed its importance in the diagnosis and monitoring of various diseases. Pathological SAA values are often detected in association with normal CRP concentrations. SAA rises earlier and more sharply than CRP. Finally, contrary to CRP, SAA presents the same trend in viral as well as bacterial infections. Although the data available on SAA in neonates are currently very limited, it is possible to postulate a role of primary importance for SAA in the management of neonatal infections.

C-Reactive Protein↗

PubMed2000

Antibiotic prophylaxis in children with relapsing urinary tract infections: review.

Recurrent urinary tract infections (UTIs) are observed in 30-50% of children after the first UTI. Of these, approximately 90% occur within 3 months of the initial episode. The basic aim of antibiotic prophylaxis in children with malformative uropathy and/or recurrent UTIs, is to reduce the frequency of UTIs. The bacteria most frequently responsible for UTI are gram-negative organisms, with Escherichia coli accounting for 80% of urinary tract pathogens. In children with recurrent UTIs and in those treated with antibiotic prophylaxis there is a greater incidence of UTI due to Proteus spp., Klebsiella spp. and Enterobacter spp., whereas Pseudomonas spp., Serratia spp. and Candida spp. are more frequent in children with urogenital abnormalities and/or undergoing invasive instrumental investigations. Several factors are involved in the pathogenesis of UTI, the main ones being circumcision, periurethral flora, micturition disorders, bowel disorders, local factors and hygienic measures. Several factors facilitate UTI relapse: malformative uropathies, particularly of the obstructive type; vesico-ureteric reflux (VUR); previous repeated episodes of cystitis and/or pyelonephritis (3 or more episodes a year), even in the absence of urinary tract abnormalities; a frequently catheterized neurogenic bladder; kidney transplant. The precise mechanism of action of low-dose antibiotics is not yet fully known. The characteristics of the ideal prophylactic agent are presented in this review, as well as indications, dosages, side effects, clinical data of all molecules. While inappropriate use of antibiotic prophylaxis encourages the emergence of microbial resistance, its proper use may be of great value in clinical practice, by reducing the frequency and clinical expression of UTIs and, in some cases such as VUR, significantly helping to resolve the underlying pathology.

Anti-Infective Agents↗

PubMed2000

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↗

PubMedDate not supplied

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↗

PubMedDate not supplied

[Reflux nephropathy in absence of obvious vesicoureteral reflux].

Although the majority of patients with vesicoureteric reflux presents DMSA scan alterations, parenchimal renal scars are found also in children without vesicoureteric reflux. Two clinical cases of reflux nephropathy without evidence of reflux are presented. Several explanations could be advocated to justify this picture, including haematogenous source of infection, inadequate timing and/or procedure of cystouretrography, intermittency of reflux, ascending bacteria, previous presence of reflux, and appearance of controlateral reflux during the natural history of a monolateral documented reflux. Tailored diagnostic and therapeutic strategy should discussed for each patient.

Child↗

PubMedDate not supplied

[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↗

PubMedDate not supplied

[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↗