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V Fanos

Publications and source records attributed to V Fanos.

At least 37 records · Page 2Linked to original sources

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↗

Transient hyperechogenicity of the renal medullary pyramids: incidence in the healthy term newborn.

A screening program was performed on 1881 clinically healthy term newborns, aimed at detecting eventual pathological conditions not diagnosed during pregnancy. Seventy-three cases of transient hyperechogenicity of the renal medullary pyramids were observed, involving one or both kidneys with either sectorial or diffuse pattern. None of the neonates examined had evidence of renal dysfunction and follow-up ultrasound scans demonstrated complete resolution of the sonographic picture. Medullary hyperechogenicity is not rare in healthy term newborns (3.9%); it presents rapid resolution and should be considered in differential diagnosis of pathological conditions.

Female↗

Cystatin C in healthy women at term pregnancy and in their infant newborns: relationship between maternal and neonatal serum levels and reference values.

Human cystatin C, a basic low molecular mass protein with 120 amino acid residues, is freely filtered by the glomerulus and almost completely reabsorbed and catabolized by the proximal tubular cells. Cystatin C has been recently proposed as a new sensitive endogenous serum marker for the early assessment of changes in the glomerular filtration rate. To define a reference basis for future clinical investigations in the perinatal period, we investigated the relationship between maternal and neonatal serum cystatin C in comparison with that of creatinine. We also defined reference values in healthy women at full-term pregnancy and in full-term newborns over the first 5 days of life. Seventy-eight women with uncomplicated pregnancy, aged between 19 and 40 years, and their infant newborns (43 males, 35 females) were enrolled in the study. The gestational age ranged from 37 to 43 weeks, and the birth weight from 2.50 to 4.15 kg. Blood samples were taken from all the women immediately before delivery and from their newborns at birth, 72 and 96 h after birth. Maternal and neonatal renal function was evaluated by standards parameters and by calculating creatinine clearance. In all serum samples, we measured cystatin C, creatinine, and urea. At term gestation, serum cystatin C ranged from 0.64 to 2.30 mg/L. At birth, serum cystatin C values ranged from 1.17 to 3.06 mg/L, significantly decreasing after 3 and 5 days of life. No correlation was found between maternal and neonatal serum cystatin C values (r = 0.09). As cystatin C serum levels in newborns are not significantly correlated with the respective maternal levels, neonatal serum cystatin C may originate almost exclusively in the neonate.

Adult↗

Antimicrobial survey of urinary tract isolates from a pediatric department.

The epidemiology of urinary tract colonization/infection in children admitted during 1996 to the Pediatric Department of the University of Verona has been studied; 501/1959 urine cultures were positive (25.57%). 584 microorganisms (64.89% Gram-negative, 24.82% Gram-positive, 10.27% fungi) were isolated. The highest rate of Gram-negative isolation (80.0%) was observed in infants, while the highest rate of Gram-positive isolation (29.6%) was found in newborns admitted to the neonatal intensive care unit. Escherichia coli was the most frequently isolated microorganism in infants and children, but not in newborns. A 3-fold increase in resistant E. coli strains to cotrimoxazole/sulfamethoxazole and amoxicillin/clavulanic acid was documented during the last 3 years in this pediatric population. Our observations underline the importance of the survey of microbial maps in pediatric departments in order to optimize therapeutic and preventive choices.

Anti-Bacterial Agents↗

Candida infections in newborns: a review.

Despite adequate treatment, nosocomial fungal infections have become an increasingly important cause of morbidity, extended hospitalization, and mortality in critically ill newborn babies. Furthermore, the high incidence of central nervous system involvement in septic newborns frequently results in serious neurological damage and psychomotorial sequelae. The prevention of fungal colonization in the population at risk, together with prompt diagnosis and treatment, are an efficient combination which lead to a better outcome of neonatal fungal infections. New drugs characterized by great efficacy and tolerance have recently been employed in clinical practice. This article summarizes certain aspects of Candida spp. infections in the neonatal period with regard to multisystemic presentation and involvement.

Candidiasis↗

Antibacterial-induced nephrotoxicity in the newborn.

Antibacterials are the primary cause of drug-induced kidney disease in all age groups and these agents bring about renal damage by 2 main mechanisms, namely, direct and immunologically mediated. For some antibacterials (aminoglycosides and vancomycin) nephrotoxicity is very frequent but generally reversible upon discontinuation of the drug. However, the development of acute renal failure with these agents is possible and its incidence in the newborn seems to be increasing. Antibacterials are very often used in the neonatal period especially in very low birthweight neonates. The role of neonatal age in developing nephrotoxicity has still to be defined. Since the traditional laboratory parameters of nephrotoxicity are abnormal only in the presence of substantial renal damage, the identification of early non-invasive markers of the renal damage (urinary microglobulins, enzymes and growth factors) is of importance. Aminoglycosides and glycopeptides are still frequently used, either alone or in combination, despite their low therapeutic index. Numerous factors intervene in bringing about the kidney damage induced by these 2 classes of antibacterials, such as factors related to the antibacterial itself and others related to the associated pathology as well as pharmacological factors. Nephrotoxicity can be caused by the beta-lactams and related compounds. Their potential to cause nephrotoxicity decreases in the order: carbapenems > cephalosporins > penicillins > monobactams. Third generation cephalosporins are frequently used in neonates. However, they are well tolerated compounds at the renal level. The nephrotoxicity of other classes of antibacterials is not discussed either because they are only used in neonates in exceptional circumstances, for example, chloramphenicol and cotrimoxazole (trimethoprim-sulfamethoxazole) or are not associated with significant nephrotoxicity, for example macrolides, clindamicin, quinolones, rifampicin (rifampin) and metronidazole. Antibacterial-induced nephrotoxicity is an important parameter to be considered when treating the newborn and this is particularly true when use of a combination of different antibacterials and/or drugs with a nephrotoxic potential is being considered. However, other parameters, such as antibacterial spectrum, pharmacokinetics, post-antibacterial effect, clinical efficacy, general adverse effect profile and cost, must also be considered in the choice of antibacterial therapy in the neonate. Knowledge of the renal safety of antibacterials and the correct approach to therapeutic drug monitoring may be useful elements for preventing iatrogenic renal disorders.

Aminoglycosides↗

Antibiotics in neonatal infections: a review.

The bacteria most commonly responsible for early-onset (materno-fetal) infections in neonates are group B streptococci, enterococci, Enterobacteriaceae and Listeria monocytogenes. Coagulase-negative staphylococci, particularly Staphylococcus epidermidis, are the main pathogens in late-onset (nosocomial) infections, especially in high-risk patients such as those with very low birthweight, umbilical or central venous catheters or undergoing prolonged ventilation. The primary objective of the paediatrician is to identity all potential cases of bacterial disease quickly and begin antibacterial treatment immediately after the appropriate cultures have been obtained. Combination therapy is recommended for initial empirical treatment in the neonate. In early-onset infections, an effective first-line empirical therapy is ampicillin plus an aminoglycoside (duration of treatment 10 days). An alternative is ampicillin plus a third-generation cephalosporin such as cefotaxime, a combination particularly useful in neonatal meningitis (mean duration of treatment 14 to 21 days), in patients at risk of nephrotoxicity and/or when therapeutic monitoring of aminoglycosides is not possible. Another potential substitute for the aminoglycoside is aztreonam. Triple combination therapy (such as amoxicillin plus cefotaxime and an aminoglycoside) could also be used for the first 2 to 3 days of life, followed by dual therapy after the microbiological results. In late-onset infections the combination oxacillin plus an aminoglycoside is widely recommended. However, vancomycin plus ceftazidime (+/- an aminoglycoside for the first 2 to 3 days) may be a better choice. Teicoplanin may be a substitute for vancomycin. However, the initial approach should always be modified by knowledge of the local bacterial epidemiology. After the microbiological results, treatment should be switched to narrower spectrum agents if a specific organism has been identified, and should be discontinued if cultures are negative and the neonate is in good clinical condition. Penicillins and third-generation cephalosporins are generally well tolerated in neonates. There is controversy regarding whether therapeutic drug monitoring of aminoglycosides will decrease toxicity (particularly renal damage) in neonates, and on the efficacy and safety of a single daily dose versus multiple daily doses of these drugs. Toxic effects caused by vancomycin are uncommon, but debate still exists over the need for therapeutic drug monitoring of this agent. When antibacterials are used in neonates, accurate determination of dosage is required, particularly for compounds with a low therapeutic index and in patients with renal failure. Very low birthweight infants are also particularly prone to antibacterial-induced toxicity.

Anti-Bacterial Agents↗

Cystatin C in paediatric nephrology. Present situation and prospects.

Cystatin C is a small basic protein with a MW of 13,359 Daltons, consisting of a non-glycosylated polypeptide chain containing 120 amino-acid residues. Cystatin C is produced in all the nucleated cells of the human body and its output rate is constant. The kidney is the main catabolic site of cystatin C, since the protein, by virtue of its low MW and its positive charge at normal pH, is freely filtered by the glomerulus and almost completely reabsorbed, catabolised and broken down in the cells of the proximal convoluted tubule. It is practically entirely filtered via the glomerular membrane, without any significant tubular secretion. The constant production rate of cystatin C in all the tissues, its elimination via the glomerular filter and its non-dependence on many extrinsic factors, including sex, age, diet, inflammation, are potentially ideal conditions for an endogenous biochemical marker of glomerular filtration. A recent method for determining cystatin C, is based on an immune reaction, could increase its clinical application. Not many studies have been conducted to date on cystatin C in children. The cystatin C concentration was higher during the first few days of life (range: 1.64-2.59 mg/L) with a rapid reduction during the first 4 months. Beyond the first year of life, cystatin C concentration became constant, with a reference range of 0.7-1.38 mg/L. On the basis of the data currently available, neonatal serum cystatin C would appear to derive from the newborn itself. In fact no correlations were found between maternal and neonatal serum cystatin C values. Cystatin C determination appears to be at least equivalent to serum creatinine measurement for the assessment of glomerular filtration rate in children. Further extended studies are needed to investigate these aspects more thoroughly in neonates.

Adolescent↗

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↗

A review of teicoplanin in the treatment of serious neonatal infections.

UNLABELLED: Gram-positive bacteria, notably coagulase negative staphylococci, have become an important cause of infection in neonates. Furthermore, many of these pathogens are now resistant to multiple antibacterial agents. Teicoplanin, a glycopeptide antibiotic, is active against a broad range of Gram-positive pathogens, including methicillin-resistant staphylococci. It has advantages over vancomycin in terms of tolerability, with a lower propensity to cause nephrotoxicity and anaphylactoid-like reactions, and in terms of ease of administration and monitoring requirements. The clinical utility of teicoplanin in neonates with Gram-positive infections has been investigated in several noncomparative studies. Clinical and bacteriological response rates in 173 neonates treated with teicoplanin 8-10 mg/kg intravenously or intramuscularly once daily after a loading-dose regimen of 10-20 mg/kg per day have ranged from 80%-100% and 83%-100%, respectively. Few adverse events related to teicoplanin have been reported in this patient population. CONCLUSION: Teicoplanin (8-10 mg/kg) administered intravenously or intramuscularly once daily after a loading-dose regimen of 15-20 mg/kg per day appears to be an effective and well tolerated treatment for Gram-positive infections in neonates.

Anti-Bacterial Agents↗

Evaluation of antibiotic-induced nephrotoxicity in preterm neonates by determining urinary alpha 1-microglobulin.

alpha 1-Microglobulin (alpha 1-m, protein HC), a relatively low molecular weight protein of about 31,000 daltons, was measured in urine of three groups of 34 preterm neonates: group A consisted of 9 healthy preterm neonates; groups B (n = 13) and C (n = 12) consisted of preterm neonates with suspected or confirmed bacterial infections. Immediately after birth, all group B neonates were treated with ampicillin and aztreonam in combination, and all group C neonates were treated with oxacillin and amikacin in combination. To optimize amikacin administration, computerized individually tailored doses were administered. Urine samples were obtained from a short collection in sterile bags on the 1st, 4th, and 7th day after delivery in all infants. Urinary alpha 1-m concentrations were measured by a turbidimetric method (latex agglutination photometric immunoassay) and results were expressed as a ratio to urinary creatinine. In group A, urinary alpha 1-m concentrations were stable after birth. In group C, alpha 1-m excretion increased immediately within the 1st day of treatment, and over the 1st week of life urinary alpha 1-m levels were significantly higher than in group A (P = 0.033). These data support the conclusion that amikacin administration was the most important factor inducing renal tubular dysfunction in the neonates of group C.

Alpha-Globulins↗

Low molecular mass proteins and urinary enzymes in amniotic fluid of healthy pregnant women at progressive stages of gestation.

OBJECTIVES: Amniotic fluid alpha1-microglobulin (alpha1-m) and beta2-microglobulin (beta2-m) levels, as well as N-acetyl-beta-D-glucosaminidase (NAG) and alanine aminopeptidase (AAP) activities, were measured in the course of uncomplicated pregnancies to assess their variations as gestation progresses. DESIGN AND METHODS: Samples were obtained from 141 healthy pregnant women divided into three groups on the basis of gestational stage. Quantitative estimation of proteins was performed immunometrically and enzyme activities were determined spectrophotometrically. RESULTS: It was found that, during pregnancy, alpha1-m and beta2-m concentrations as well as AAP activity significantly decrease, although their reduction patterns vary. Controversial results were found for NAG activity: the normalization of values for amniotic fluid creatinine significantly changed the reduction pattern of this enzyme. No statistically significant differences were found between male and female fetuses for amniotic fluid values of the biochemical substances studied. CONCLUSIONS: The behavior observed for alpha1-m, beta2-m, and AAP might be linked to the progressive development and maturation of fetal renal tubular function. Amniotic fluid total NAG activity seems not to depend only on fetal urinary excretion.

Acetylglucosaminidase↗

Staphylococcus epidermidis isolation and antibiotic resistance in a neonatal intensive care unit.

Bacterial ecology was studied in 1114 newborns (355 at term, 759 preterm) admitted to a neonatal intensive care unit (NICU) during a three year period. Bacterial samples were taken in each newborn from external ear canal, pharynx and eyes in all patients, and from endotracheal tube, umbilical catheter and blood in selected patients. The predominant flora was characterized by gram-positive microorganisms (63.53%), Staphylococcus epidermidis representing 34.68% of all isolated strains. S. epidermidis isolation increased significantly with time (p < 0.002) and was highest in summer. The percentage of S. epidermidis resistant strains to oxacillin (63.8%) and to amikacin (17.8%) was high. This is the antimicrobial combination we commonly employ as empirical treatment of suspected bacterial infection in our NICU. Knowledge of characteristics of local microbial flora seems important in order to optimize preventive and therapeutic policies for neonatal infections.

Drug Resistance, Microbial↗

Tubular proteins and enzyme content in the amniotic fluid.

Amniotic fluid is the product of many substances and fetal urine is considered to be one of the principal components. Only a few reports have been published describing the concentration of microglobulins and urinary enzymes in the amniotic fluid. We determined the levels of alpha 1-m, beta 2-m, AAP and NAG, in 154 samples of amniotic fluid (103 early determinations and 51 late determinations) as a function of gestational age. We observed a statistically significant decrease in concentration of alpha 1-m (P < 0.001), beta 2-m (P < 0.01) and AAP (P < 0.001) when early and late amniotic fluid samples were compared. A statistically significant increase of NAG (P < 0.01) and creatinine (P < 0.01) was also found. A significant correlation was observed between alpha 1-m and beta 2-m, and between AAP and NAG, respectively. The potential role of urinary enzyme and microglobulin determination in amniotic fluid as an index of fetal kidney development, is discussed.

Acetylglucosaminidase↗

Pharmacokinetics of amikacin in neonates.

Only a few data have thus far been published on the pharmacokinetics of amikacin in neonates. To gain further information on this issue, we studied a series of 32 neonates who were treated with amikacin for suspected or documented bacterial infection. Nineteen neonates were preterm (mean gestational age = 32.0 +/- 3.6 weeks, mean body weight = 1.74 +/- 0.81 kg) while the remaining 13 were full-term (mean body weight = 3.19 +/- 0.82 kg). The 32 neonates were given amikacin by intramuscular route. A total of 121 concentrations were measured (average number of concentrations per patient = 3.8; range 3-6). To estimate amikacin pharmacokinetic parameters, the serum concentration values of the drug were fitted to the one-compartment pharmacokinetic model. The calculated pharmacokinetic parameters were the following (mean +/- SD): clearance = 64.6 +/- 30.8 ml/h/kg; volume of distribution = 0.655 +/- 0.414 liters/kg; half-life = 7.6 +/- 4.4 h. These results are similar to the values reported previously, with the important exception of the volume of distribution, which was considerably higher in our study. The intraindividual variability of amikacin pharmacokinetics was evaluated by the standard two-stage method yielding an intraindividual variability coefficient of 28.9%. No previous estimate of this parameter has as yet been published. The population parameters of amikacin in neonates, derived from the present study (i.e. coefficient for intraindividual variability and means +/- SD for clearance and volume of distribution), can be applied to a further series of neonates to facilitate the prospective use of the bayesian method for individualizing amikacin dosage.

Amikacin↗

[Ceftazidime in common infections in childhood. Experience in 262 cases].

We analyzed the clinical data collected from an open multicentre study (in 40 Hospital and University centres) with aim to evaluate clinical and bacteriological efficacy and safety of Ceftazidime (CTZ) in common infections of pediatric patients. The data were from 262 patients (137 M, 125 F) mean age 5.13 +/- 3.65 yrs (range 3 m. to 12 yrs). 158 pts with low respiratory tract infection, 32 pts. with upper respiratory tract infection and 72 pts. with urinary tract infection, were treated with CTZ (dose 50 mg/kg/die; i.v. or i.m.) for a mean of 9.4 days. The overall success rate was 96.2% (76.7% cured + 19.5% improved). In the evaluable cases (108) the bacteriological eradication rate was 92.18%. The safety of CTZ was good; adverse events (2 rash and 1 diarrhoea) were observed only in 3 patients. All events had moderate intensity and did not require drug withdrawal.

Age Factors↗

Pharmacokinetics and renal tolerance of aztreonam in premature infants.

Aztreonam (30 mg/kg of body weight) was administered intravenously over 3 min every 12 h to 30 preterm neonates divided into two groups according to gestational age (mean age for group A was less than 30 weeks and mean age for group B was greater than 30 weeks) and birth weight (mean weight for group A was less than 1,500 g and mean weight for group B was greater than 1,500 g). Blood and urine samples were analyzed by microbiological assay. The pharmacokinetics were described by one-compartment and noncompartment models. The mean half-life and clearance for premature infants weighing less than 1,500 g were 5.33 +/- 3.61 h and 1.52 +/- 1.33 ml/min/kg, respectively; for those weighing more than 1,500 g, the values were 4.08 +/- 2.28 h and 2.41 +/- 2.10 ml/min/kg, respectively. The mean urinary concentration of aztreonam in 15 premature infants during the first 6 h of therapy was 242.72 +/- 188.19 micrograms/ml, with a mean percentage of elimination of 13.29%. Urinary excretion of N-acetyl-beta-D-glucosaminidase (a specific and sensitive test for the detection of drug-induced renal tubule damage) did not show significant differences in our group of premature infants compared with that in a control group. The dose of 30 mg/kg and a dosage interval of 8 to 12 h could be recommended for the treatment of suitable bacterial infections in all premature infants.

Acetylglucosaminidase↗