Change of pulsatility index of the fetal middle cerebral artery after auditory stimulation in no risk pregnancies and in pregnancies with gestational hypertension.

PURPOSE: An aim was to determine the degree and the mode of variation of PI of middle cerebral artery in no risk pregnancies and in pregnancies with gestational hypertension, after the constant sound stimuli. METHOD: Study included 343 patients divided in two groups. Group 1: low risk pregnancies and group 2: gestational hypertension. Ultrasound prenatal auditory screening was performed after the 27th week of gestation. RESULTS: The percentage of fetuses with increase of cerebral blood flow was slightly higher in the pregnancies with hypertension. CONCLUSION: An average change of PI of median cerebral artery was higher in this group.

Diagnostic role of initial renal cortical scintigraphy in children with the first episode of acute pyelonephritis.

OBJECTIVE: Assessment of the first febrile urinary tract infection (UTI) in children has been the subject of debate for many years. Diagnosis of acute pyelonephritis (APN) is usually based on clinical and biological data. The clinical usefulness of early Tc-99m DMSA scintigraphy remains controversial, although it may influence the type and duration of treatment. The aim of this study was to assess the role of initial cortical scintigraphy in the detection of early renal parenchymal damage in children highly suspected of having APN and to compare the scintigraphic findings with selected clinical/laboratory parameters and ultrasonography. METHODS: A prospective study was conducted in 34 infants and young children (18 boys, 16 girls), aged 1.5-36 months (mean 9.8 ± 8.7 months), hospitalized with a first episode of clinically suspected APN. Within the first 5 days after admission, Tc-99m DMSA renal scintigraphy, ultrasonography (US), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), white blood cell count (WBC) and urine analyses were performed. RESULTS: DMSA scintigraphy showed changes consistent with APN in 27/34 (79%) patients, with a mean age of 10.9 months, including 12 males (44%) and 15 (56%) females. Out of 9 febrile children with negative urine culture and supportive evidence of UTI, scintigraphy showed parenchymal involvement in 8 children (24% in the whole group, 30% in scintigraphically documented APN). There were no statistically significant correlations between the frequency or size of the initial scintigraphic abnormalities and age, sex, body temperature, CRP levels or ESR. A CRP level of >54 mg/L and a WBC of >13,300/mm³ had sensitivities of 56 and 59% and specificities of 86 and 71%, respectively. US showed changes consistent with APN in 7/34 (21%) in the whole group and in 7/27 (26%) patients with positive cortical scan (p < 0.05). CONCLUSION: Initial DMSA renal scintigraphy is a sensitive method for the early diagnosis of APN in young children and is useful in the assessment of the severity of kidney injury even in patients with negative urine culture. Clinical, biological and ultrasound parameters do not identify children with renal damage. Normal DMSA study, excluding parenchymal involvement and late sequelae, could minimize the use of scintigraphy in the follow-up and reduce the redundancy of cystography.

Oxidative stress in fetal distress: potential prospects for diagnosis.

Our aim was to investigate the relation between fetal distress and oxidative stress. Fetal distress was associated with increased concentration of superoxide in the fetal blood and with significant increase of the level of H2O2 in both maternal and fetal blood. The activity of superoxide dismutase was increased roughly sixfold (p<0.01) in the maternal (7330 +/- 2240 U/g of hemoglobin in controls (C) and 36811 +/- 16862 U/g in fetal distress (FD)) and fetal blood (C: 5930 +/- 2641 U/g; FD: 41912 +/- 17133 U/g). In contrast, fetal distress was related to a considerable decrease of catalase activity in both maternal (C: 26011 +/- 8811 U/g; FD: 7212 +/- 1270 U/g) and fetal blood (C: 37194 +/- 9191 U/g; FD: 6173 +/- 1965 U/g). From this we concluded that in fetal distress, the maternal and fetal bloods are exposed to superoxide- and H2O2-mediated oxidative stress, which could be initiated by hypoxic conditions in the fetal blood and placenta. A tremendous increase/decrease of the activities of superoxide dismutase/catalase in the blood of women bearing a distressed fetus in comparison to healthy subjects implies that the assessment of superoxide dismutase/catalase activity could be of use for establishing a timely and accurate ante- or intrapartum diagnosis of fetal distress.

Investigation of blood perfusion and metabolic activity of brain tumours in adults by using 99mTc-methoxyisobutylisonitrile.

OBJECTIVES: (i) To examine blood perfusion and metabolic activity of various brain tumours using radionuclide cerebral angiography (RCA) and single-photon emission tomography (SPET) after a single dose of Tc-methoxyisobutylisonitrile (MIBI). (ii) To examine if the inclusion of RCA can improve insight into the relative contribution of tumour perfusion to the uptake of MIBI shown by SPET, and to improve evaluation of tumour biology. (iii) To determine the value and the roles of MIBI in the management of brain tumour patients. METHODS: Fifty adult patients (38 male, 12 female) with a total of 56 intracranial space-occupying lesions have been included prospectively, 37 of which were newly diagnosed and the remaining with signs of recurrence/rest of earlier resected and irradiated brain tumours. The control group consisted of nine volunteers with no evidence of organic cerebral disease. Scintigraphic examination consisted of a dynamic first-pass study lasting 60 s (3 s/frame) and two SPET studies (60 projections each, 25 s/projection), starting 15 min and 2 h after intravenous injection of MIBI. Regions of interest of the tumour and normal brain tissue were drawn on RCA and both early and delayed SPET slices. The following tumour/brain activity ratios have been calculated: (i) tumour perfusion index (P); (ii) early uptake index (E); (iii) delayed uptake index (D); and(iv) retention index (R). Analogous indices have been calculated from the same examinations performed in controls, reflecting maximal physiologic regional variations of perfusion and uptake in brain tissue. RESULTS: Mean P of various brain tumours (low-grade gliomas 0.98, anaplastic gliomas 1.14, glioblastoma multiforme 1.20, metastases 1.09, lymphomas 1.08) differ little from each other and do not exceed maximal physiologic regional variations of cerebral perfusion (1.33), with the exception of meningioma (1.87, F=2.83, P=0.015). The receiver operating characteristics curve analysis of P showed that for the cut-off value of 1.45 the sensitivity for distinguishing meningioma from other tumours is 75%, specificity 87%, positive predictive value 33% and negative predictive value 97%. Mean E of malignant brain tumours (8.3, n=31, 23 primary, eight secondary), except anaplastic gliomas (3.5, n=5), differed significantly (P=0.02) from those of benign gliomas (3, n=9) but not from that of meningioma (11.9, n=4). The cut-off value for distinguishing malignant from benign lesions on the basis of E set at 4.8 resulted in sensitivity 67%, specificity 75%, accuracy 70%, positive predictive value 80% and negative predictive value 60%. D and R showed tendency of wash-out of MIBI from meningiomas, but otherwise did not improve the results substantially. CONCLUSION: Integrated results of RCA and SPET with Tc-MIBI indicate that blood perfusion, blood-tumour barrier permeability and metabolic activity of the tumour are all very important for the resultant uptake shown by SPET. If the perfusion index is less than 1.45, then meningioma can be ruled out. Early SPET is recommendable for distinguishing glioblastoma from low-grade gliomas, as a complement to standard magnetic resonance imaging and/or computed tomography.

[Normal values of cerebral blood flow velocities in neonates].

INTRODUCTION: There was used color Doppler ultrasonography (cD-USI), allowing simultaneous examination of parenchymal and vascular cerebral structures. The evaluation of blood flow velocities in cerebral arteries is important in the assessment of cerebral circulation in hypoxic-ischaemic and haemorrhagic brain damage in neonates. OBJECTIVE: The aim of this study was to estimate normal values of cerebral blood flow velocities (CBFV) and Doppler indices--pulsatility index (PI) and resistance index (RI)--in the anterior cerebral artery (ACA) during the first days of life in infants. METHODS: CBFV, PI and RI were obtained during the first week of life with cD-US in 70 infants divided in four groups of gestational age (GA): < or =28 gestational weeks (GW); 29-32 GW; 33-36 GW; and > or =37 GW. Infants with congenital malformations, severe perinatal asphyxia, cerebral haemorrhagic lesion, DAP or severe hypotension were excluded. RESULTS: The mean GA of infants was 34.5 +/- 5.5 GW (range 26-40 GW) and the mean birth weight (BW) was 2540 +/- 950 g (range 750-4000 g). In the 1st group of 10 infants, < or =28 GW, the mean BW was 950 +/- 110 g and values of RI were 0.59 +/- 0.10 and PI 1.06 +/- 0.080. In the 2nd group of 20 infants, 29-32 GW, the mean BW was 1350 +/- 290 g and values of RI were 0.60 +/- 0.10 and PI 1.10 +/- 0.15. In the 3rd group of 20 infants, 33-36 GW, the mean BW was 1950 +/- 750 g and values of RI were 0.63 +/- 0.08 and PI 1.15 +/- 0.30. In the 4th group of 20 infants, > or =37 GW, the mean BW was 3540 +/- 950 g and values of RI were 0.65 +/- 0.05 and PI 1.18 +/- 0.35. CONCLUSION: Values of CBFV progressively increase with GA and BW due to progressive increase of cardiac output, blood pressure and closing of ductus arteriosus. Values of RI and PI gradually increase with GA and BW as a result of progressive maturation and opening of vascular cerebral bed with a reduction of the cerebrovascular resistance.

[The serum level of C-reactive protein in neonatal sepsis].

INTRODUCTION: C-reactive protein (CRP) is the most common diagnostic marker of infection. OBJECTIVE: Objectives of this study were to determine the serum CRP level in neonates with sepsis and establish the influence of gestational age (GA) on the CRP level in the first few weeks after birth. METHOD: Diagnosis of neonatal sepsis was established by the presence of clinical signs of sepsis, isolation of the causative agent of sepsis and abnormal haematological parameters. All neonates were divided into two groups: early onset sepsis (EOS) and late onset sepsis (LOS). According to GA all neonates were divided into three groups: < 32 GA, 32-36 GA and > or = 37 GA. Serum CRP was measured 0-72 h after the onset of signs and symptoms of infection. RESULTS: This study included all neonates with sepsis at our Institute during 2003. EOS was diagnosed in 130 neonates (mean age was 33 weeks; range 27-41 weeks) and 33 infants (mean age 29 weeks; range 27-38 weeks). We defined a relevant CRP response as a concentration of > 10 mg/l for term and near term neonates and > 5 mg/l for preterm neonates. The maximum concentrations of CRP were reached 48 hr after the first symptoms of neonatal sepsis. CONCLUSION: CRP levels are proportional with increasing GA and body weight in EOS. The effects of gestational age do not influence CRP levels in LOS. Maturation changes in the immune system are the most likely explanation for this and partly the organisms responsible for an infection may be different at different gestational ages and also in EOS and LOS. There is no correlation with serum CRP levels and with the severity of the disease and bad prognosis in EOS.