Search PubMed⌕ Search

Biomedical subjects

R Manfredi

Publications and source records attributed to R Manfredi.

At least 91 records · Page 5Linked to original sources
PubMed2000

Severe chronic pancreatitis versus suspected pancreatic disease: dynamic MR cholangiopancreatography after secretin stimulation.

PURPOSE: To assess whether secretin stimulation improves visualization of the pancreatic ducts at magnetic resonance (MR) cholangiopancreatography (MRCP) in patients with severe chronic pancreatitis or suspected pancreatic disease. MATERIALS AND METHODS: Thirty-one patients (group 1) with chronic pancreatitis and 84 patients (group 2) with clinical and/or laboratory findings suggestive of pancreatic disease who did not have ductal alterations at ultrasonography (US) and/or computed tomography (CT) underwent MRCP before and up to 10 minutes after secretin stimulation. Size of the main pancreatic duct (head, body, tail) and duodenal filling before and after secretin stimulation were measured quantitatively. Image quality, number of main pancreatic ductal segments visualized, visualization of side branches, ductal narrowing, endoluminal filling defects, and presence of pancreas divisum were analyzed qualitatively. RESULTS: In both groups, the size of the main pancreatic duct increased significantly 3 minutes after secretin stimulation. Reduced duodenal filling was detected in patients with severe chronic pancreatitis (P < .001). The number of segments of the main pancreatic duct visualized improved from 85 (91%) to 93 (100%) of 93 in group 1 and from 164 (65%) to 245 (97%) of 252 (P < .001) in group 2. Visualization of side branches improved from 22 (71%) to 31 (100%) of 31 in group 1 and from three (4%) to 53 (63%) of 84 (P < .001) in group 2. Pancreas divisum was visualized in one additional patient in group 1 and in six additional patients in group 2. CONCLUSION: The administration of secretin improves visualization of the pancreatic ducts and helps in the evaluation of exocrine reserve.

Adolescent↗
PubMed2000

Focal liver lesions: evaluation of the efficacy of gadobenate dimeglumine in MR imaging--a multicenter phase III clinical study.

PURPOSE: To evaluate gadobenate dimeglumine (Gd-BOPTA) for dynamic and delayed magnetic resonance (MR) imaging of focal liver lesions. MATERIALS AND METHODS: In 126 of 214 patients, MR imaging was performed before Gd-BOPTA administration, immediately after bolus administration of a 0.05- mmol/kg dose of Gd-BOPTA, and 60-120 minutes after an additional intravenously infused 0.05-mmol/kg dose. In 88 patients, imaging was performed before and 60-120 minutes after a single, intravenously infused 0.1-mmol/kg dose. T1- and T2-weighted spin-echo and T1-weighted gradient-echo images were acquired. On-site and blinded off-site reviewers prospectively evaluated all images. Intraoperative ultrasonography, computed tomography (CT) during arterial portography, and/or CT with iodized oil served as the reference methods in 110 patients. RESULTS: Significantly more lesions were detected on combined pre- and postcontrast images compared with on precontrast images alone (P <. 01). All reviewers reported a decreased mean size of the smallest detected lesion and improved lesion conspicuity on postcontrast images. All on-site reviewers and two off-site reviewers reported increased overall diagnostic confidence (P <.01). Additional lesion characterization information was provided on up to 109 (59%) of 184 delayed images and for up to 50 (42%) of 118 patients in whom dynamic images were assessed. Gd-BOPTA would have helped change the diagnosis in 99 (47%) of 209 cases and affected patient treatment in 408 (23%) of 209 cases. CONCLUSION: Gd-BOPTA increases liver lesion conspicuity and detectability and aids in the characterization of lesions.

Adult↗
PubMed2000

Pancreas divisum and "santorinicele": diagnosis with dynamic MR cholangiopancreatography with secretin stimulation.

PURPOSE: To evaluate the usefulness of magnetic resonance (MR) cholangiopancreatography (MRCP) before and after secretin administration in diagnosing santorinicele in patients with pancreas divisum. MATERIALS AND METHODS: One hundred seven patients suspected of having pancreatic disease underwent MRCP before and after secretin administration (S-MRCP). S-MRCP images were evaluated for pancreas divisum and santorinicele and for size of the main pancreatic duct and santorinicele. The onset of duodenal filling was calculated on dynamic S-MRCP images. RESULTS: Pancreas divisum was detected in five (5%) of 107 patients at MRCP and in 10 (9%) of 107 patients at S-MRCP. Santorinicele was detected in three (21%) of 14 patients at MRCP and in an additional four (seven [50%] of 14) patients at S-MRCP in patients with pancreas divisum. Santorinicele was confirmed in six of seven patients at endoscopic retrograde cholangiopancreatography (ERCP); in one of seven patients, ERCP was unsuccessful. The duct of Santorini was significantly (P: <.05) larger in the pancreatic head in patients with pancreas divisum and santorinicele (3.6 mm) compared with those with only pancreas divisum (2.2 mm). A noteworthy reduction in size of the pancreatic duct (26%) and of the santorinicele (63%) was observed after sphincterotomy. The onset of duodenal filling was delayed significantly in patients with santorinicele (2.1 vs 1.3 minutes; P: <.05). CONCLUSION: S-MRCP helps in identifying pancreas divisum and santorinicele, which may be the cause of impeded pancreatic outflow.

Adolescent↗
PubMed2000

Moraxella catarrhalis pneumonia during HIV disease.

To assess the role of Moraxella catarrhalis complications in the setting of HIV disease, and to evaluate their occurrence and outcome according to several epidemiological, clinical, and laboratory parameters, the clinical records of 2123 consecutive HIV-infected patients hospitalized in a 9-year period were retrospectively reviewed, and 4 cases of community-acquired M. catarrhalis pneumonia were identified. Three adult patients had a diagnosis of AIDS and severe concurrent immunodeficiency (with a CD4+ lymphocyte count below 60 cells/microL), while the fourth case involved a child with vertical HIV disease. Leukopenia and neutropenia were never present, but no patient received a potent antiretroviral regimen at the time of disease onset. A concurrent respiratory infection by Streptococcus pneumoniae and Mycobacterium tuberculosis was recognized in 2 of 4 patients. Isolated M. catarrhalis strains were susceptible to all tested antimicrobial compounds (save ampicillin in 2 cases), and appropriate antimicrobial treatment led to clinical and microbiological cure in all described episodes. Only 8 cases of HIV-associated Moraxella spp. disease have been reported to date in seven different literature reports (6 cases of pneumonia, and 1 of septicemia). According to our experience, M. catarrhalis may be responsible for appreciable morbidity among patients with advanced HIV infection, especially when a low CD4+ cell count or coexisting respiratory disease are present. Clinicians and microbiologists who care for HIV-infected patients should carefully consider the potential pathogenic role of Moraxella spp. organisms.

AIDS-Related Opportunistic Infections↗
PubMed2000

Silent oophoritis due to cytomegalovirus in a patient with advanced HIV disease.

A case of isolated necrotizing cytomegalovirus (CMV) oophoritis disclosed only by necropsy studies in a patient with AIDS, is described. This unusual case report is discussed with a review of the literature dealing with CMV involvement of genital organs in the immunocompromised host, and in patients with HIV infection and AIDS.

AIDS-Related Opportunistic Infections↗
PubMed2000

Development of acute psychotic disorders and HIV-1 infection.

OBJECTIVE: To gain more understanding about the relationship between human immunodeficiency virus type 1 (HIV-1) infection and new-onset psychosis, we compared clinical and immunological findings, psychiatric symptoms, global cognitive performance and, when available, computerized tomography (CT) findings between HIV-1-seropositive patients with new-onset psychosis and well-matched nonpsychotic HIV-1-seropositives. METHODS: Two groups of subjects: HIV-1-seropositives with new-onset psychosis (n = 12) and HIV-1-seropositives without psychosis (n = 15) were recruited through outpatient departments. Organic Delusional Syndrome and Organic Hallucinosis were clinically diagnosed using DSM-III-R diagnostic criteria. Of the baseline participants, twenty-two participated in the two-year follow-up examination. RESULTS: The prevalence of new-onset psychosis in HIV-1-infected subjects was 3.7 per 100 (95% C.I. = 1.6-5.7). HIV-1-seropositive persons with new-onset psychosis had more frequently a positive past psychiatric history, no antiretroviral therapy, and a lower global cognitive performance than did the nonpsychotic HIV-1-seropositives. CT was positive, showing generalized brain atrophy, in three out of nine patients. Remission of psychotic symptoms was observed only in two HIV-1-seropositive persons with new-onset psychosis. Death occurred in two psychic HIV-1-seropositives with simple loosely held delusions. Autopsy results showed that cortical sulci and ventricle size were graded as with moderate/severe enlargement. CONCLUSIONS: New-onset psychosis in HIV infected patients could raise considerable problems in deciding whether a presentation is organic or functional. An interaction of the disease or of psychologically "having" the disease with the presence of a psychotic reaction should also be considered. Interestingly, a protective effect of antiretroviral therapy for new-onset psychosis is suggested.

AIDS Dementia Complex↗
PubMed2000

Evaluation of the accuracy of gadobenate dimeglumine-enhanced MR imaging in the detection and characterization of focal liver lesions.

OBJECTIVE: We evaluated the extent to which hepatic lesion characterization and detection is improved by using gadobenate dimeglumine for enhancement of MR images. MATERIALS AND METHODS: Eighty-six patients were imaged before gadobenate dimeglumine administration, immediately after the 2 mL/sec bolus administration of a 0.05 mmol/kg dose (dynamic imaging), and at 60-120 min after the IV infusion at 10 mL/min of a further 0.05 nmol/kg dose (delayed imaging). The accuracy for lesion characterization was assessed for a total of 107 lesions. Sensitivity for lesion detection was assessed for a total of 149 lesions detected on either intra-operative sonography, iodized oil CT, CT during arterial portography, or follow-up contrast-enhanced CT as the gold standard. RESULTS: The accuracy in differentiating benign from malignant liver lesions increased from 75% and 82% (the findings of two observers) on unenhanced images alone, to 89% and 80% on dynamic images alone (p<0.001, p = 0.8), and to 90.7% when combining the unenhanced and dynamic image sets (p<0.001, p = 0.023). Delayed images did not further improve accuracy (90% and 91%; p = 0.002, p< 0.05). A similar trend was apparent in terms of accuracy for specific diagnosis: values ranged from 49% and 62% on unenhanced images alone, to 76% and 70% on combined unenhanced and dynamic images (p<0.001, p = 0.06), and to 75% and 70% on inclusion of delayed images (p<0.001, p = 0.12). The sensitivity for lesion detection increased from 77% and 81% on unenhanced images alone, to 87% and 85% on combined unenhanced and dynamic images (p = 0.001, p = 0.267), and to 92% and 89% when all images were considered (p<0.001, p = 0.01). CONCLUSION: Contrast-enhanced dynamic MR imaging with gadobenate dimeglumine significantly increases sensitivity and accuracy over unenhanced imaging for the characterization of focal hepatic lesions, and delayed MR imaging contributes to the improved detection of lesions.

Adult↗
PubMed2000

[Modeling incomplete observations].

Incomplete observations, common in epidemiology as in many other fields, lead to problems of bias, precision and power. Using a simple example with 3 binary variables, we discuss situations where the observed odds ratio is biased. We present and compare the main strategies of analysis: complete observations modeling, missing data indicator, weighted analysis, simple imputation, multiple imputation, selection models, shared variable models.

Bias↗
PubMed2000

[Antiretroviral therapy in HIV infection. Effects of the introduction of new drugs on health care expenditures, 1994-1999].

The administration of antiretroviral compounds to our cohort of HIV-infected patients was assessed since 1994, on the ground of some epidemiological, clinical, and therapeutic variables. During the six-year study period, a significant increase of mean prescription rate of overall anti-HIV agents was observed, with a nearly 10-fold rise of mean prescribed daily doses per 1,000 patients-year. In particular, lamivudine and indinavir represented the most frequently administered drugs, among nucleoside analogues and protease inhibitors, respectively. A significant increase of the percentage of HIV-infected patients undergoing combined antiretroviral therapy (79.3% in 1999), and the mean number of drugs prescribed per patient (3.02 in 1999), was concurrently detected. The progressive changes of antiretroviral therapy guidelines were responsible for a nearly 16-fold increase of expenditures directly related to antiretroviral drug administration in 1999 compared with 1994 (with over 41% of costs related to protease inhibitors). On the other hand, a substantial modification of HIV disease evolution occurred in our patient cohort in terms of absolute morbidity and mortality figures, as expressed by a drop of notified AIDS cases and AIDS-related deaths ranging from 2.5 to 5 times, during the considered period.

Acquired Immunodeficiency Syndrome↗
PubMed2000

[Influenza].

Influenza outbreaks remain today among the most serious and intractable health problems owing to high rates of morbidity and high economic costs. Periodical epidemics and pandemics in temperate regions of the world are due to high genetic variability of influenza viruses, which concerns primarily haemagglutinin and neuraminidase antigens (antigenic drift and shift). Most influenza infections are self-limited, but they cause increased mortality in high-risk groups of population (such as the elderly and the subjects with chronic diseases) and increased morbidity in the general population, with loss of productivity and high health costs. During the past thirty years, efforts to control influenza have focused on the use of inactivated vaccines in high-risk groups and of two antiviral drugs, amantadine and rimantadine. However, the wide spread of influenza in all population groups and the limits of adamantane compounds induced to investigate novel approaches for prevention and control of flu. The new live attenuated, cold-adapted, trivalent intranasal vaccine was shown to be highly effective in children against influenza A (H3N2) and B viruses. The new antiviral drugs (zanamivir and oseltamivir), neuraminidase inhibitors, reduced the median time to alleviation of the major symptoms of influenza by 1-2 days. These advances in the last few years will certainly modify our approaches to influenza treatment and prevention.

Acetamides↗
PubMed1999

Doppler sonographic assessment of functional response of the right and left portal venous branches to a meal.

PURPOSE: The aim of our study was to quantitate by Doppler sonography the blood flow in the right and left portal vein branches before and after a standard meal. We also assessed the functional response of the right and left lobes of the liver. METHODS: Portal blood flow was measured by Doppler sonography in the left and right portal vein branches and main portal trunk in 20 healthy volunteers in both fasting and postprandial states. The ratio between portal blood flow and liver volume (determined by MRI) was the portal flow index (PFI). RESULTS: Before the meal, a statistically significant difference in portal blood flow volume was observed between the right and left portal branches (p < 0.01). The right PFI (0.83 ml/minute/cm3) and left PFI (1.1 ml/minute/cm3) were also significantly different (p < 0.01). The increase in portal venous blood flow after a meal was found to be greater in the left portal branch (128%) than in the right portal branch (78%). The postprandial PFI also differed significantly (right, 1.54 ml/minute/cm3; left, 2.5 ml/minute/cm3). CONCLUSIONS: These findings suggest that the left lobe of the liver has a better postprandial compliance than the right lobe has.

Adult↗
PubMed1999

Delayed MR imaging of hepatocellular carcinoma enhanced by gadobenate dimeglumine (Gd-BOPTA).

The purpose of this study was to determine the efficacy of gadobenate dimeglumine (Gd-BOPTA)-enhanced magnetic resonance (MR) imaging for evaluation of hepatocellular carcinoma HCC. MR images were obtained in 14 patients with 31 HCC nodules as a part of a phase III clinical trial. T1- and T2-weighted images were obtained before and after iv administration of 0.1 mmol/kg of Gd-BOPTA. Two blinded readers evaluated pre- and delayed postcontrast images separately for detection of tumor nodules. Quantitative measurements of signal-to-noise (SNR) and tumor/liver contrast-to-noise (CNR) ratios were also performed. A signal/intensity ratio was calculated. Tumor enhancement was correlated with histologic findings. Consensus agreement of precontrast T1- and T2-weighted images revealed 23/31 HCC nodules in 14 patients; postcontrast T1-weighted images demonstrated 24/31 HCC nodules in the same number of patients. Combining both pre- and postcontrast images, 27/31 lesions were detected. Four patients had four well-differentiated HCC nodules detected only on postcontrast images, while three well-differentiated lesions in two patients were only seen on precontrast images. Quantitative evaluation showed an SNR ratio increase in both liver parenchyma and HCC nodules, as well as a significant increase in the absolute CNR ratio on postcontrast T1-weighted gradient-recalled images (P < 0.05). Well-differentiated HCC lesions showed a greater enhancement than poorly differentiated HCC lesions.

Aged↗
PubMed1999

Flavobacterium spp. organisms as opportunistic bacterial pathogens during advanced HIV disease.

OBJECTIVE: To assess the role of Flavobacterium spp. infection in patients with HIV disease. METHODS: Clinical charts of 2412 consecutive HIV-infected patients hospitalized in a 8-year period were retrospectively reviewed, to identify all cases of Flavobacterium spp. infections, and to evaluate their occurrence and outcome according to several epidemiological, clinical, and laboratory parameters. RESULTS: Six patients out of 2412 (0.25%), developed Flavobacterium spp. complications: septicaemia in five cases, and pneumonia in the remaining patient, with F. meningosepticum and F. odoratum isolated in two cases and one case, respectively, and unnamed Flavobacterium spp. organisms in the remaining three cases. Flavobacterium spp. organisms were responsible for six out of 1939 overall episodes of non-mycobacterial bacterial diseases observed in our patient group (0.31%). All patients were severely immunocompromised, showing a prior diagnosis of AIDS, a mean CD4+ lymphocyte count of 64.2 (range 12-187) cells/microl, and a mean neutrophil count of 1.143 (range 700-1600) cells (range 700-1600) cells/microl. Antibiotic, corticosteriod, or cotrimoxazole treatment was carried out during the month preceding disease onset by three, two and five patients, respectively. Community-acquired and nosocomial Flavobacterium spp. disease were equally frequent, but the latter occurred with a significantly lower mean neutrophil and CD4+ cell count. Antimicrobial susceptibility assays showed complete sensitivity to ciprofloxacin, and variable resistance to ureidopenicillins, ceftazidime, imipenem, aztreonam, and aminoglycosides. An appropriate antimicrobial regimen obtained clinical and microbiological cure in all cases, in absence of related mortality or relapses. CONCLUSIONS: Since only one episode of HIV-associated F. (Sphingobacterium) multivorum complication has been described to date, our series represents the largest one dealing with Flavobacterium spp. infection in the setting of HIV disease. Our experience suggests that Flavobacterium spp. organisms may play a pathogenic role in patients with advanced HIV disease, even when some commonly recognized risk factors are lacking (i.e. indwelling catheters, instrumentation, IV drug abuse), while a very low CD4+ lymphocyte count, leukopaenia-neutropaenia, and concurrent AIDS-related infectious complications may act as important predisposing factors. In view of the infrequent occurrence of these infections, early suspicion is essential for both clinicians and microbiologists facing immunocompromised patients at risk for invasive bacterial complications. Flavobacterium spp. organisms should be taken into consideration as nosocomial- or community-acquired opportunistic pathogens, due to their relationship with advanced immunodeficiency and their elevated resistance to many antimicrobial agents commonly used against Gram-negative bacterial pathogens.

AIDS-Related Opportunistic Infections↗
PubMed1999

The changing face of AIDS-related opportunism: cryptococcosis in the highly active antiretroviral therapy (HAART) era. Case reports and literature review.

Only nine cases of AIDS-related cryptococcosis have been reported until now in patients receiving highly active antiretroviral therapy (HAART), all of them with abnormal clinical features. Two HIV-infected patients who experienced an atypical relapse of cryptococcosis shortly after the start of HAART and despite maintenance antifungal treatment, are described. Six different relapses of cryptococcal meningitis were observed in a 28-month period in a patient who obtained a poor immune recovery after HAART (as shown by a CD4+ lymphocyte count ranging from 78 to 149 cells/microL, opposed to a baseline level of 98 cells/microL). On the other hand, a patient with favorable immunological response to HAART (as expressed by a CD4+ count growing from 7 to 186 cells/microL), experienced isolated multiple indolent cryptococcal abscesses involving head, neck, the anterior thoracic wall, and regional lymph nodes, with repeatedly negative cultures, and diagnosis obtained by both histopathologic study and positive serum antigen assay. Both our case reports are representative of novel correlations between opportunistic pathogens and immune reactivity, descending from the introduction of HAART. The first episode describes an exceedingly elevated number of disease relapses despite HAART and antifungal maintenance treatment, which may descend from an incomplete immune response to antiretroviral therapy, possibly responsible for failure in obtaining eradication of yeasts, but also for lack of disease dissemination (usually leading to a lethal multivisceral involvement in the pre-HAART era). The abnormal disease course and localization of second reported patient well depicts an "immune reconstitution syndrome" probably representing a flare-up of a latent fungal infection, caused by a rapidly effective HAART. In patients treated with HAART, AIDS-related cryptococcosis cannot therefore be ruled out by the absence of neurological involvement, and by persistingly negative cultures.

AIDS-Related Opportunistic Infections↗