Hypersensitivity reactions to iodinate contrast media in Italy: a retrospective study. Characteristics of patients and risk factors.

SUMMARY: Objective. The purpose of the study was to describe the characteristics of patients experiencing hypersensitivity reactions (HRs) to iodinated contrast media (ICM) in a large Italian population and to investigate potential risks factors in order to obtain a risk stratification, helpful in the management of these patients. Methods. Data of 407 patients investigated in 9 Italian Allergy Centers for suspected HRs to ICM were analyzed and compared with a control group of 152 subjects that tolerated one or more ICM-enhanced examinations. The univariate and multivariate logistic regression model was used to evaluate associated factors. Results. The mean age of reactive patients was 61 years and 60% were female; 67% of patients reported immediate reactions and 35% experienced the reaction, more frequently with immediate onset, at the first examination in life. Iomeprol, iopromide and iodixanol were the most frequent culprit agents and 20% of patients showed a positive skin test result. Previous adverse reactions to ICM were reported by 15.6% of patients, whereas 35% of subjects experienced the reaction, more frequently immediate, after the first ICM-enhanced examination in their life. The multivariate analysis showed that male gender and age > 65 were associated with ICM reactions as protective factors [ORadja = 0.51; 95% CI: 0.33-0.77 and ORadja = 0.60; 95% CI: 0.39-0.92 respectively]. Cardio-vascular disease [ORadja = 2.06; 95% CI: 1.22-3.50)], respiratory allergy [ORadja = 2.30; 95% CI: 1.09-4.83)] and adverse drug reactions [ORadja = 1.99; 95% CI: 1.05-3.77)] were identified as risk factors for ICM reactions. Food allergy was not significantly associated with reactions [ORadja = 1.51; 5% CI: 0.41-5.56]. Conclusions. This is the largest study on Italian patients experiencing hypersensitivity reactions to ICM. Most results are in line with other studies, showing some association with factors that could influence the incidence of hypersensitivity reactions but not allowing an easy risk stratification.

Comparison between magnetic resonance imaging and rigid rectoscopy in the preoperative identification of intra- and extraperitoneal rectal cancer.

AIM: Accurate preoperative discrimination between extra- and intraperitoneal rectal cancer has important treatment implications. Our main objective was to compare the diagnostic performance of MRI with rigid rectoscopy (RRS) in assessing the location of rectal cancers above or below the peritoneal reflection (PR), using the findings obtained during abdominal surgery for treatment of the cancer as the reference standard. We also compared the accuracy of MRI and RRS in assessing the level of the lower border of the tumour from the anal verge. METHOD: Patients with rectal carcinoma awaiting surgery underwent MRI and RRS. The MRI images were reviewed by two abdominal radiologists who determined the location of the inferior border of the tumour in relation to the PR. Receiver-operating characteristics (ROC) curve analysis was performed to determine the diagnostic performance of RRS at different cut-off values. RESULTS: The sensitivity and specificity were 98.15% and 100%, respectively, for MRI, and 100% and 76.92%, respectively, for RRS at a cut-off value of < 10 cm. The mean level of the lower border of the tumour from the anal verge was 68 ± 44.3 mm on RRS and 73.5 ± 42.4 mm on MRI (P = 0.25), with a trend towards overestimation with MRI. CONCLUSION: RRS is still the main means of assessing the level of a rectal tumour from the anal verge, but MRI has value in determining the level of the tumour in relation to the PR, which cannot be seen on endoscopy.

Measurement of liver iron overload: noninvasive calibration of MRI-R2* by magnetic iron detector susceptometer.

An accurate assessment of body iron accumulation is essential for the diagnosis and therapy of iron overload in diseases such as thalassemia or hemochromatosis. Magnetic iron detector susceptometry and MRI are noninvasive techniques capable of detecting iron overload in the liver. Although the transverse relaxation rate measured by MRI can be correlated with the presence of iron, a calibration step is needed to obtain the liver iron concentration. Magnetic iron detector provides an evaluation of the iron overload in the whole liver. In this article, we describe a retrospective observational study comparing magnetic iron detector and MRI examinations performed on the same group of 97 patients with transfusional or congenital iron overload. A biopsy-free linear calibration to convert the average transverse relaxation rate in iron overload (R(2) = 0.72), or in liver iron concentration evaluated in wet tissue (R(2) = 0.68), is presented. This article also compares liver iron concentrations calculated in dry tissue using MRI and the existing biopsy calibration with liver iron concentrations evaluated in wet tissue by magnetic iron detector to obtain an estimate of the wet-to-dry conversion factor of 6.7 ± 0.8 (95% confidence level).

Crohn's disease: prevalence of intestinal and extraintestinal manifestations detected by computed tomography enterography with water enema.

BACKGROUND: Computed tomography enterography (CTE) may detect the presence, severity, and extent of bowel inflammation in patients with Crohn's disease (CD). The aim of our study was to assess, among a cohort of 22 histologically proven CD patients, the prevalence of disease distribution, behavior, anastomotic recurrence and extraintestinal manifestations detected by an original CTE technique. METHODS: Two radiologists reviewed 221 CTEs performed providing both small and large bowel distension by oral administration of neutral contrast material and trans-rectal introduction of a water enema (CTE-WE). RESULTS: Ileal CD was detected in 116 CTE-WEs (52.4%), including 71/116 (61.2%) non-stricturing/non-penetrating, 17/116 (14.6%) stricturing, and 28/116 (24.1%) penetrating forms. Colonic CD was appreciable in 35 (15.8%) patients, including 18/35 (51.4%) non-stricturing/non-penetrating, 6/35 (17.1%) stricturing, and 11/35 (31.4%) penetrating forms. Ileocolic CD was present in 52 (23.5%) CTE-WEs, including 30/52 (57.7%) non-stricturing/ non-penetrating; 3/52 (5.7%) stricturing, and 19/52 (36.5%) penetrating forms. In 10/221 patients (4.5%), upper gastrointestinal involvement (UGI) was present. Perianal disease was observed in 17/221 patients (7.7%). Fistulas were present in 52 (23.5%) and abscesses in 24 (10.8%) CTE-WEs, respectively. Among 57/221 (25.8%) patients who had undergone a disease-related intestinal resection, in 30/57 cases (52.6%) CD recurrence at the anastomosis was present. 4/221 patients (1.8%) with a histologically confirmed intestinal neoplastic stenosis were observed. Sacroiliitis (24%) was found to be prevalent over hepatic steatosis (10.8%), cholelithiasis (8.6%), and nephrolithiasis (4%). CONCLUSIONS: CTE-WE represents a comprehensive imaging technique which may demonstrate bowel inflammation and CD extraintestinal manifestations. A peculiar prevalence of UGI involvement and neoplastic strictures were observed. In our study the prevalence of sacroiliitis resulted higher than previously reported.

Multidetector computerized tomography enteroclysis vs. rectal water contrast transvaginal ultrasonography in determining the presence and extent of bowel endometriosis.

OBJECTIVES: To compare the accuracy of multidetector computerized tomography enteroclysis (MDCT-e) and rectal water contrast transvaginal ultrasonography (RWC-TVS) in determining the presence and extent of bowel endometriosis. METHODS: This prospective study included 96 patients of reproductive age with suspicion of bowel endometriosis. Patients underwent MDCT-e and RWC-TVS before operative laparoscopy. Findings of MDCT-e and RWC-TVS were compared with histological results. The severity of pain experienced during MDCT-e and RWC-TVS was measured by a 10-cm visual analog scale. RESULTS: Fifty-one patients had bowel endometriotic nodules at surgery. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy for the diagnosis of rectosigmoid endometriosis were 95.8% (46/48), 100.0% (48/48), 100.0% (46/46), 96.0% (48/50) and 97.9% (94/96) for MDCT-e and 93.8% (45/48), 97.9% (47/48), 97.8% (45/46), 94.0% (47/50) and 95.8% (92/96) for RWC-TVS. MDCT-e was associated with more intense pain than was RWC-TVS. CONCLUSIONS: MDCT-e and RWC-TVS have similar accuracy in the diagnosis of rectosigmoid endometriosis, but patients tolerate RWC-TVS better than they do MDCT-e.

Imaging of renal leiomyomas.

BACKGROUND: Renal leiomyomas are rare benign tumors of the kidney which can be found at autopsy as small capsular nodules in about 5% of cases. The clinical incidence of such lesions is much smaller, and only case reports or small series have been reported in the imaging literature. PURPOSE: To describe the imaging characteristics observed in a series of eight patients with pathology-proven asymptomatic leiomyomas of the kidney. MATERIAL AND METHODS: We reviewed the imaging findings observed in eight patients with pathologically proven asymptomatic renal leiomyomas discovered during studies performed for reasons unrelated to the kidney. All patients had undergone computed tomography (CT), two ultrasonography, and one magnetic resonance imaging (MRI). RESULTS: Lesions ranged in size from 1.2 to 13 cm. Six were at the periphery of the kidney, compressed its outer surface, but did not cause disruption of the cortex; two involved the renal cortex. All had regular outer margins. A cleavage plane between the tumor and the kidney was revealed at CT and/or ultrasonography in three of the cases located at the periphery. At ultrasonography, leiomyomas appeared hypoechogenic. At CT, they were slightly hyperdense before contrast medium injection; all were hypodense to the renal cortex after contrast medium. Four were homogeneous, two were slightly heterogeneous, and the remaining two were frankly heterogeneous. The lesion studied by MRI, which was homogeneous at the postcontrast CT study, had a heterogeneous structure on both T1- and T2-weighted images, with internal areas of hypointensity on T1. CONCLUSION: There are some imaging findings that can help to suggest the diagnosis of renal leiomyomas. First, their density: all tumors examined before contrast were hyperdense to the kidney, with density similar to that of muscles, and all had lower enhancement than the adjacent renal parenchyma. Second, the location and margins of the tumors: most were peripheral, without involvement of the renal cortex and with well-defined margins. Although not pathognomonic for a renal leiomyoma, the combination of these findings should include leiomyoma in the list of differential diagnoses.

Schedule-selective biochemical modulation of 5-fluorouracil: a phase II study in advanced colorectal cancer.

Based on experimental findings suggesting that 5-fluorouracil (FUra) may have different mechanisms of action depending on the schedule of administration, we generated the hypothesis that biochemical modulation of this fluoropyrimidine should be schedule specific. We thus tested the activity of a hybrid regimen consisting of two biweekly cycles of FUra bolus (600 mg/m2) modulated by pretreatment (24-h interval) with methotrexate (200 mg/m2), alternating with a 3-week continuous infusion of FUra (200 mg/m2/day) modulated by low-dose (6S)leucovorin (20 mg/m2 bolus weekly). Thirty-three consecutive patients with advanced measurable colorectal cancer and no prior therapy for metastatic disease entered the study from February 1992 to August 1993. They were treated with two biweekly cycles of FUra bolus (600 mg/m2) preceded by (24-h interval) methotrexate (200 mg/m2), alternating with a 3-week continuous infusion of FUra (200 mg/m2/day) modulated by low-dose (6S)leucovorin (20 mg/m2 bolus weekly). The median Eastern Cooperative Oncology Group performance status was 1; the liver was the only metastatic site in 17 patients. Treatment outcome was evaluated by computed tomographic scan in all patients, except for two. Three complete and 13 partial responses were obtained among these 33 patients (response rate, 48%; 95% confidence limits, 31-66%). Performance status (Eastern Cooperative Oncology Group) influenced clinical response. The combined complete response and partial response rate was 69%, 33%, and 25% in patients with an Eastern Cooperative Oncology Group performance status of 0, 1, and 2, respectively (chi2, 4.6, P = 0.032, two-tailed Mantel test for trend). After a median follow-up time of 26 months, 10 patients are still alive. The median progression-free survival and overall survival were 9.5 and 20.2 months, respectively. No toxic deaths or grade 4 toxicity occurred. The incidence of grade 3 toxicity per patient in any cycle was: mucositis 6%, diarrhea 3%, and vomiting 3% for the bolus part and 21%, 3%, and 6%, respectively, for the continuous infusion part of the regimen. Hand-foot syndrome occurred in 27% of the patients treated with the continuous infusion regimen.

High resolution ultrasound anatomy of normal Achilles tendon.

To evaluate the ultrasound (US) appearance of the normal Achilles tendon at increasing frequency and establish an anatomical correlation for US findings, 30 normal tendons were examined in vivo and three in vitro with 10 MHz and 15 MHz mechanical sector probes. Side-by-side comparison was performed in vitro between the sonograms and the corresponding anatomical sections. Two tendinous portions were detected by presence of an internal acoustic interface which had different appearances: one (type I) or two (type II) continuous lines of increased thickness and greater reflectivity than adjacent fibrils; or displacement (type III) of the distal portion of the well insonated sector of the tendon body. When, on coronal scans of the tendon, no intratendinous linear echoes of increased reflectivity were visible, the two portions of the tendon were identified through the converging course of their bundles (type 0 pattern). Different echogenicity allowed the detection of two tendinous portions, also on axial images. Scanning of isolated tendons allowed precise location of these interfaces at the boundary between anatomically distinct tendinous portions arising from the soleus and gastrocnemius muscles. Although the normal Achilles tendon is commonly regarded as a uniform structure by US, the use of high resolution probes allows identification of its constituent portions. Their identification may be useful to avoid misdiagnoses of pathological findings.

Imaging of patients with pancreaticobiliary diversion for obesity: post-operative anatomy and findings in small bowel obstruction.

Pancreaticobiliary diversion is a surgical procedure undertaken for obesity. It consists of a distal gastrectomy with a long Roux-en-Y reconstruction, the enteroenterostomy being placed 200 cm distal to the gastroenterostomy and 50 cm proximal to the ileocaecal valve. Three intestinal limbs are recognized: (a) the alimentary loop from the gastroenterostomy to the enteroenterostomy; (b) common loop from the enteroenterostomy to the ileocaecal valve and (c) pancreaticobiliary loop from the duodenum to the enteroenterostomy. The radiological findings in 15 pancreaticobiliary diversion patients with small bowel obstruction were reviewed (15 plain abdominal radiographs, 13 ultrasound (US), 8 CT) and compared with 20 plain abdominal radiographs, 10 US, and 10 CT studies performed for other causes in patients with pancreaticobiliary diversion and 15 CT scans from non-operated patients. After pancreaticobiliary diversion the pancreaticobiliary loop was completely air-free. In the patients operated on more than 1 year previously, alimentary and common loops were significantly larger than the pancreaticobiliary loop and small bowel loops of non-operated subjects. Obstruction of the pancreaticobiliary loop arrests only the flow of pancreaticobiliary secretions with non-specific clinical findings. Plain abdominal radiographs were not diagnostic in all but two cases with radiographically detectable dilated fluid filled loops. Air-fluid levels were never apparent. US and CT showed markedly dilatated intestinal loops and duodenum. Obstruction of the alimentary and common loops presented with symptoms, clinical signs, and radiological findings more typical for bowel obstruction in intact subjects.

[Diagnostic and therapeutic problems in angiodysplasias of the digestive tract]. / Problemi diagnostici e terapeutici nelle angiodisplasie dell'apparato digerente.

After a review of recent literature on angiodysplasias of the digestive system, a diagnostic procedure based on personal experience is proposed for haemorrhagic patients. Criteria for the selection of treatment protocols are then proposed for cases where angiodysplasia is recognised as the cause of the bleeding.

[The role of segmental transit time in the large intestine in the diagnosis of severe constipation]. / Il ruolo dei tempi di transito settoriale del crasso nella diagnosi della stipsi grave.

Segmental small and large bowel transit time of 25 healthy volunteers have been studied, as a control group, by means of radio-opaque markers prepared and administered according to an original method. The same study has been subsequently carried out on 37 patients suffering for chronic non organic constipation. The resulting data, though poorly homogeneous, may however, be plotted in 8 classes; each class groups subjects presenting very similar segmental transit time whose changes are less than 4 hours. The first class gathers the 8.1% of the cases, presenting in increased small bowel transit time; the patients of the second class (5.4%) has resulted affected by "right colon constipation syndrome"; another 5.4% of patients, plotted in the third class have shown a permanence time of the markers in the transverse colon of about 190 hours, while the 10.8% fourth class and the 16.2% fifth class have presented a 97 and 150 hours' one respectively. The patients of the sixth class (21.6%) have shown long lasting permanence of markers in the left colon and in the rectum. The 13.5% of cases, gathered in seventh class, has shown an increased transit time through the whole colon, while at last the eight class (19.0% of patients) has resulted affected by dischezia. The described method has thus revealed useful in the study of bowel segmental transit time from a topographic diagnostic point of view.

[Antibiotic preparation in operations on the large intestine. Experimental study]. / La preparazione antibiotica negli interventi sul grosso intestino. Studio sperimentale.

A controlled study was mounted to assess the possible benefit of a single phlebo administration of 600 mg lincomycin 1 hr prior to colon surgery, in addition to the erythromycin + neomycin combination proposed by Nichols, as a means of constituting a further pharmacological barrier to the spread of anaerobic bacteria. The study currently comprises two groups of 15 patients fully comparable with regard to pathology distribution and randomly assigned to the E.N. and the E.N.L. protocol respectively. Six instances of septic complication have been observed, five in the group prepared with E.N. and 1 prepared with E.N.L. No significance can be attached to the different incidence of complications in the two arms of the study, owing to the small number of cases examined.

Characterization of benign hepatic tumors arising in fatty liver with SonoVue and pulse inversion US.

BACKGROUND: We describe the spectrum of contrast-enhancement patterns of benign hepatic tumors arising in fatty liver on contrast-enhanced ultrasound (US). METHODS: Sixteen patients (12 women and four men) with 27 benign hepatic tumors (17 hemangiomas, eight focal nodular hyperplasias, and two hepatocellular adenomas) arising in fatty liver underwent baseline and pulse inversion US after administration of SonoVue. Two experienced radiologists evaluated baseline echogenicity and dynamic enhancement pattern of each lesion in comparison with adjacent liver parenchyma. RESULTS: After administration of SonoVue, in the arterial phase 13 of 17 hemangiomas showed peripheral globular enhancement and one showed a rim of peripheral enhancement, followed by progressive centripetal fill-in, which was complete in 10 of 14 cases and incomplete in four. Three of 18 hemangiomas showed rapid and complete fill-in in the arterial phase. Eight of eight focal nodular hyperplasias became hyperechoic in comparison with adjacent liver parenchyma in the arterial phase and slightly hyperechoic or isoechoic in the portal venous and delayed phases. Both adenomas showed strong arterial contrast enhancement that became less intense in the portal venous and delayed phases. CONCLUSION: Contrast-enhanced US after administration of SonoVue enables depiction of typical contrast-enhancement patterns in most benign hepatic tumors arising in fatty liver, thus providing useful clues for characterization.

Multidetector-row helical CT enteroclysis.

The authors illustrate the technique for small-bowel imaging using enteroclysis with multidetector-row computed tomography (MDCT), underscoring the important role played by CT in the assessment of the small bowel thanks to the advent of first the spiral and later the multidetector technique. The paper makes a detailed comparison of the various methods that have been used in CT study of the small bowel and proposes a standardised technique to achieve correct distension of bowel loops and adequate evaluation of bowel wall vascularity, making reference to the well-consolidated experiences of the various Italian research groups. The paper accurately describes the different procedures required for CT assessment of the small bowel, from nasojejunal intubation to the selection of the most appropriate acquisition phases for assessment of bowel wall vascularity.

Multidetector-row CT enteroclysis: indications and clinical applications.

This paper examines the diagnostic potential of multislice computed tomography enteroclysis (MSCT-E) to detect and assess different diseases affecting the small bowel, emphasising the increasingly important role assumed by the technique in the study of this anatomical region. After a short summary of the technical aspects, we discuss the different findings that can be observed during an MSCT-E study and that enable detection of small-bowel disease and, if necessary, assessment of the extent and stage of disease.