Household transmission of haemolytic uraemic syndrome associated with Escherichia coli O104:H4, south-western France, June 2011.

Following the outbreak of haemolytic uraemic syndrome (HUS) on June 2011 in south-western France, household transmission due to Escherichia coli O104:H4 was suspected for two cases who developed symptoms 9 and 10 days after onset of symptoms of the index case. The analysis of exposures and of the incubation period is in favour of a secondary transmission within the family. Recommendations should be reinforced to prevent person-to-person transmission within households.

Treatment of gastrointestinal hemorrhage.

BACKGROUND: We assessed the value of selective arteriography in the diagnosis and management of acute gastrointestinal hemorrhage. METHODS: We reviewed the records of 107 consecutive patients who had gastrointestinal hemorrhage and underwent selective arteriography between January 1992 and October 2003: 10 had upper gastrointestinal bleeding, 79 had lower gastrointestinal bleeding, and 18 had varicose bleeding with portal hypertension. Selective embolization was attempted in 15 patients to obtain hemostasis. Angiographic findings were reviewed and prospective reports were compared with the final diagnosis and outcome. RESULTS: Of 129 angiographic studies, 36 correctly revealed the bleeding site and 93 were negative. Extravasation was seen in 24 cases at the level of stomach (n = 2), duodenum (n = 1), small bowel (n = 5), or colon (n = 16). Indirect signs of bleeding sources were identified in 12 patients (stomach in one, small bowel in four, large bowel in four, liver in three). Transcatheter embolization induced definitive hemostasis in 11 of 15 patients (73%), namely in the stomach (n = 2), small bowel (n = 3), colon (n = 7), and liver (n = 3). Three patients required surgery after embolization. CONCLUSION: Abdominal arteriography may localize gastrointestinal bleeding sources in approximately one-third of cases. Selective embolization may provide definitive hemostasis in most instances.

Parametric and quantitative analysis of MR renographic curves for assessing the functional behaviour of the kidney.

The aim of this study was to refine the description of the renal function based on MR images and through transit-time curve analysis on a normal population and on a population with renal failure, using the quantitative model of the up-slope. Thirty patients referred for a kidney MR exam were divided in a first population with well-functioning kidneys and in a second population with renal failure from ischaemic kidney disease. The perfusion sequence consisted of an intravenous injection of Gd-DTPA and of a fast GRE sequence T1-TFE with 90 degrees magnetisation preparation (Intera 1.5 T MR System, Philips Medical System). To convert the signal intensity into 1/T1, which is proportional to the contrast media concentration, a flow-corrected calibration procedure was used. Following segmentation of regions of interest in the cortex and medulla of the kidney and in the abdominal aorta, outflow curves were obtained and filtered to remove the high frequency fluctuations. The model of the up-slope method was then applied. Significant reduction of the cortical perfusion (Qc = 0.057+/-0.030 ml/(s 100 g) to Qc = 0.030 +/- 0.017 ml/(s 100 g), P < 0.013) of the medullary perfusion (Qm = 0.023 +/- 0.018 ml/(s 100 g) to Qm = 0.011 +/- 0.006 ml/(s 100 g), P < 0.046) and of the accumulation of contrast media in the medulla (Qa = 0.005 +/- 0.003 ml/(s 100 g) to Qa = 0.0009 +/- 0.0008 ml/(s 100 g), P < 0.001) were found in presence of renal failure. High correlations were found between the creatinine level and the accumulation Qa in the medulla (r2 = 0.72, P < 0.05), and between the perfusion ratio Qc/Qm and the accumulation Qa in the medulla (r2 = 0.81, P < 0.05). No significant difference was found in times to peak between both populations despite a trend showing Ta the time to the end of the increasing contrast accumulation period in the medulla, arriving later for renal failure. Advances in MR signal calibration with the building of quantitative model such as the up-slope allow to assess kinetic and haemodynamic and functional parameters of the diseased kidney.

[MRI evaluation of carpal tunnel morphology after carpal tunnel release by a retinaculum lengthening technique]. / Magnetresonanztomographische Beurteilung der Karpaltunnelmorphologie nach Medianusdekompression mittels einer retinakulumverlängernden Technik.

AIM: The benefits of maintaining the pulley function of the flexor retinaculum in carpal tunnel release by lengthening or reconstructing it have been described. Quantitative MR imaging was used to investigate the morphological changes after open carpal tunnel release by such a retinaculum lengthening technique. METHOD: Ten patients had bilateral carpal tunnel MRI pre- and postoperatively. The MRI examinations were performed with a 1.5 Tesla imaging system and wrist coils. Carpal tunnel volume, carpal arch width, median nerve position and flexor tendon position in relation to the hamate-trapezial axis were recorded . RESULTS: Like other methods of carpal tunnel release with complete division of the flexor retinaculum, the retinaculum lengthening technique showed a significant postoperative increase of carpal tunnel volume. Carpal arch width increased only slightly. There was a significant palmar displacement of the median nerve but not of the flexor tendons. CONCLUSION: The findings support the hypothesis that maintenance of the pulley function of the retinaculum may lead to an early postoperative recovery of grip strength. In spite of some difficulties in application quantitative MR imaging may be a useful tool in evaluating the carpal tunnel morphology.

Treatment of hepatocellular carcinoma at the dawn of the third millennium: liver transplantation and its alternatives.

Hepatocellular carcinoma is one of the most frequent tumors worldwide, and its frequency is increasing. The management of hepatocellular carcinoma has changed in recent years, this because screening allows to discover tumors at an earlier stage, and because of effective treatments are available, such as liver transplantation, liver resection, percutaneous ablation and transarterial chemoembolization. Each one of these treatments has its own advantages and drawbacks, and range of application according to the stage of the tumor and of the underlying liver disease. This review summarizes the recent progress in the management of HCC and the practice in our unit.

Specificity of SPIO particles for characterization of liver hemangiomas using MRI.

We investigated the specificity of superparamagnetic iron oxide (SPIO)-enhanced T1-weighted spin-echo (SE) magnetic resonance (MR) images for the characterization of liver hemangiomas. When imaging liver hemangiomas, which are the most frequent benign liver tumors, a method with very high specificity is required, which will obviate other studies, follow-up, or invasive diagnostic procedures such as percutaneous biopsy. Eighty-three lesions were examined by MR imaging at 1.5 T before and after intravenous injection of SPIO particles. Lesions were categorized as follows according to the final diagnosis: 37 hemangiomas, nine focal nodular hyperplasias (FNHs), 19 hepatocellular carcinomas (HCCs), and 18 metastases. Their signal intensity values were normalized to muscle and compared. The only lesions showing a significant increase in signal intensity ratio (lesion to muscle) on postcontrast T1-weighted SE images were hemangiomas (p < 0.001). The signal intensity ratio of hemangiomas increased on average by 70%. Based on receiver operating characteristic analysis and using a cutoff level of 50% signal increase, the specificity and sensitivity of SPIO-enhanced MR imaging for the characterization of hemangiomas would be 100% and 70%, respectively. The T1 effect of SPIO particles can help differentiate hemangiomas from other focal liver lesions such as FNHs, HCCs, and metastases and may obviate biopsy. When using SPIO particles for liver imaging, it is useful to add a T1-weighted sequence to T2-weighted images, thereby providing additional information for lesion characterization.

Diffusion-weighted MRI in cortical ischaemia.

We carried out MRI on 16 male and three female comatose patients, aged 2 days to 79 years, with suspected cortical ischaemia referred from our intensive care units. Using a head coil, and following standard imaging, including coronal fluid-attenuated inversion-recovery images, we performed diffusion-weighted imaging (DWI) using a whole-brain multislice single-shot echo-planar sequence with b 0 and 1000 s/mm2: 5-mm slices covering the whole brain, TR 7000 TE 106 ms, 128 x 128 pixels, field of view 250 mm, one excitation. Maps of apparent diffusion coefficients (ADC) were generated automatically. DWI showed cortical, basal ganglia and watershed-area high signal in all cases, associated with a decrease in ADC to 60- 80% of normal. DWI showed lesions not seen (40%) or underestimated (40%) on conventional T2-weighted imaging. Within 24 h of the onset of symptoms, DWI showed changes not readily detectable on T2-weighted images. The cortical high signal on DWI and the ADC changes, suggesting severe ischaemia rather than oedema, was found in areas known to be affected by cortical laminar necrosis. Extension to the brain stem and white matter was associated with a higher likelihood of death.

The levelling effect of solvational imbalances in the reactions of oximate alpha-nucleophiles with electrophilic phosphorus centers. Relevance to detoxification of organophosphorus esters.

A study of the reactions of oximate alpha-nucleophiles with diisopropylphosphorofluoridate (DFP) and two model phosphonates, has revealed either a levelling-off in reactivity or a bell-shaped behaviour in accordance with a critical decoupling of desolvation and bond formation (solvational imbalances); the relevance of these results to detoxification is emphasized.

[Occult breast cancer. Detection and radioguided surgery with 99mTc-MIBI]. / Carcinoma oculto de mama. Detección y cirugía radioguiada con 99mTc-MIBI.

We include those patients who present with an isolated metastasis of axillary adenopathy in the occult primary breast cancer group. Presumably, the primary tumor is a primitive breast carcinoma, unsuspected until this moment and not clinically demonstrable by mammography or ultrasonography. When no method succeeds in confirming the primary breast lesion, the patients are usually treated assuming the existing of breast cancer. Several diagnostic methods have been used to find the primary breast lesion. Magnetic Resonance imaging (MRI), Positron Emission (PET) and Doppler sonography have been used in this way and several papers present the results reached with them. Our group incorporates detection and radioguided surgery with 99mTechnetium (99mTc) methoxyisobutil isonitrile into the study of these patients. We perform a planar scintimammography and SPECT (Single Photon Emission Computed Tomography) with 99mTc-MIBI. If the radioisotopic method shows a functional image compatible with a carcinoma, a gamma detecting probe is then used to locate the lesion and guide its surgical removal. In this paper, we present the application of the technique in 5 cases and describe the technique and its possibilities. Its advantages are explained in comparison with other methods. The dosimetric values found in the performance of the technique are reported. We consider that detection and radioguided surgery with 99mTc-MIBI in the diagnosis and treatment of occult breast cancer adds an effective tool and means progress in the approach to this disease.

Pelvic haemophilic pseudotumour: management of a patient with high level of inhibitors.

Haemophilic pseudotumour (HP) is a rare but very serious complication of haemophilia. HP affects mainly patients with severe haemophilia and those who have developed antibodies to factor VIII or factor IX. We report on a 45-year-old man with haemophilia A and high titres of inhibitors who developed an extensive HP with progressive destruction of the right ilium over a period of 12 years. The different therapeutic options (conservative management by replacement therapy, surgical approach, radiotherapy, percutaneous evacuation with secondary refilled cavity and transcatheter arterial embolization) are reviewed.

[Hepatic inflammatory pseudotumor regressing with antibiotic therapy]. / Pseudo-tumeur inflammatoire hépatique régressant sous antibiothérapie.

INTRODUCTION: Inflammatory hepatic pseudo-tumors are rare, non-neoplastic lesions, and their diagnosis is usually made on hepatectomy samples. OBSERVATION: The general health of a 77 year-old patient was suddenly altered and clinical examination (and scan) revealed a hepatic tumor. Diagnosis of inflammatory hepatic pseudo-tumor was evoked by analysis of a biopsy. In view of the age and the general state of the patient we chose prolonged antibiotic therapy rather than hepatic surgery. Nine months later, the tumor had regressed. COMMENTS: Because they are rare (100 cases described), hepatic pseudo-tumors raise two questions: can diagnosis be made simply by biopsy or should one always analyze the complete sample and, if hepatectomy is contraindicated, is non-surgical treatment effective? The progression of our patient permits us to reply positively to both questions.

Modern approach of diagnosis and management of acute flank pain: review of all imaging modalities.

Acute flank pain is a common and complex clinical problem which might be caused by a variety of urinary and extraurinary abnormalities among which ureterolithiasis being the most frequent cause. Plain abdominal radiographs combined with intravenous urography (IVU) have been the standard imaging procedures of choice for the evaluation of acute flank pain over the last decades. Direct detection of even small ureteral calculi is achieved in 40-60%, whereas using indirect signs such as ureteral and renal pelvic dilatation stone detection is possible in up to 80-90% of all cases. However, IVU might be hampered by poor quality due to lack of bowel preparation, by nephrotoxicity of contrast agents, by serious allergic and anaphylactic reactions in 10% and 1% of the patients, respectively, and by significant radiation exposure. The use of ultrasonography (US) in the management of acute flank pain has been growing and when combining the findings of pyeloureteral dilatation, direct visualization of stones, and the absence of ureteral ejaculation, the sensitivity to detect ureteral dilatation can be as high as 96%. Recently, unenhanced helical CT (UHCT) has been introduced as imaging modality with a high sensitivity and specificity for the evaluation of acute flank pain. UHCT has been demonstrated to be superior since (1) it detects ureteral stones with a sensitivity and specificity from 98% to 100% regardless of size, location and chemical composition, (2) it identifies extraurinary causes of flank pain in about one third of all patients presenting with acute flank pain, (3) it does not need contrast agent, and (4) it is a time saving imaging technique being performed within 5min. Based on the data published, one can predict that UHCT will become the imaging procedure of choice for evaluation of acute flank pain within the next years. The purpose of this review is to critically evaluate the role all imaging modalities available for a modern approach of diagnosis and management of acute flank pain with regard to their sensitivity, specificity, positive and negative predictive values and their complications, toxicicty and morbidity.

Colonic diverticulitis: impact of imaging on surgical management -- a prospective study of 542 patients.

The aim of this study was to compare the performance of the CT and the water-soluble contrast enema (CE) in the diagnosis and the severity of acute left-colonic diverticulitis, and to recognize the impact of CT during the acute phase and after a first acute episode successfully treated medically. From 1986 to 1997, all patients admitted in our emergency center with clinically suspected left-colonic diverticulitis had a CE and a CT within 72 h of their admission, unless clinical findings required immediate laparotomy. They were prospectively included in the study if one or both radiological exams showed signs of acute diverticulitis and/or diverticulitis was surgically removed and histologically proven. Diverticulitis was considered moderate when CT showed localized thickening of the colonic wall (5 mm or more) and inflammation of pericolic fat and CE showed segmental lumen narrowing and tethered mucosa; it was considered severe when abscess and/or extraluminal air and/or contrast were observed on CT and when one or both of the latter signs were seen on CE. Five hundred forty-two patients entered the study; 465 patients (86%) had a CT exam, 439 (81%) had a CE, and 420 (77%) had both exams. The performance of CT is significantly superior to CE in terms of sensitivity (98 vs 92%, p<0.01), and in the evaluation of the severity of the inflammation (26 vs 9%, p<0.02). Moreover, of 69 patients who had an associated abscess seen on CT, only 20 (29%) had indirect signs of this complication on CE. During the acute phase the chances of medical treatment failure are statistically greater when diverticulitis is considered severe on CT than when it is considered moderate (26% for the severe diverticulitis vs 4% for the moderate ones, p<0.0001). After successful medical treatment of the acute episode, patients with severe diverticulitis on the CT had statistically greater incidence of secondary bad outcome than patients with moderate diverticulitis (36 vs 17%, p<0.0001). Computed tomography should be preferred to CE as the initial radiological exam of diverticulitis because of its statistically significant superiority in sensitivity and for its statistically much higher performance in the detection of severe infection, especially when an abscess is associated with the disease. The severity of diverticulitis on CT is statistically predictive of the risk of medical treatment failure during the acute phase and of the chances of bad secondary outcome after a successful medical treatment of the first episode.

Role of nasopharyngeal culture in antibiotic prescription for patients with common cold or acute sinusitis.

The aim of the present study was to assess the hypothesis that, when present in nasopharyngeal secretions, Streptococcus pneumoniae. Haemophilus influenzae, and Moraxella catarrhalis play a pathogenic role early in the course of an upper respiratory tract infection. Adults with a clinical diagnosis of acute sinusitis or common cold were enrolled. Participants were randomly assigned in a double-blind manner to receive azithromycin 500 mg daily or placebo for 3 days. The effect of treatment on symptom evolution in the predefined subset of patients with Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis in their nasopharyngeal secretions was assessed. Of 265 patients enrolled, 132 received placebo and 133 azithromycin. Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis was identified in nasopharyngeal secretions of 77 patients (29%). In this predefined subgroup of patients with Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis, resolution of symptoms by day 7 occurred in 73% of those treated with azithromycin compared with 47% of those who received placebo (P=0.007). The median time before resolution of symptoms was 5 days in the azithromycin group compared to 7 days in the placebo group. Respiratory complications requiring antibiotic treatment occurred in 19% of patients in the placebo group and in 3% of the azithromycin group (P=0.025). In the remaining 188 patients without Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis, resolution of symptoms by day 7 was similar in both groups (69% in the placebo group vs. 64% in the azithromycin group [P=0.75]). Antibiotic treatment is of clinical benefit for patients with acute sinusitis or common cold when Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis is present in nasopharyngeal secretions. This observation provides new insights into the pathogenic role of these bacteria in the early stage of the common cold.

[Sentinel lymph nodes in breast cancer. Multidisciplinary approach; critical analysis of the learning curve; results obtained with a radiopharmaceutical not previously utilized]. / Ganglio centinela en cáncer de mama. Abordaje multidisciplinario; análisis crítico de la curva de aprendizaje; resultados obtenidos con un radiofármaco no utilizado anteriormente.

Detection of the sentinel node is slowly becoming a new and promising procedure to stage patients suffering from breast cancer. Various articles have attempted to analyze objectively the predictive value of the histopathological examination to reveal the presence of metastatic cells in the axillary node without having to carry out an axillary dissection. In this paper, 60 patients with breast cancer (T up to 3 cm, clinically negative axilla) have been studied. A colloid bound to 99m Technetium was injected. Intra-surgical radioguided detection of the sentinel lymph node was performed and this was excised and its pathology was analyzed. After a complete axillary dissection was performed. With this technique it was possible to predict the condition ot the axilla in 96.5% of the cases and the sensitivity of the method was 92%. A training program on this technique has been developed and its application is suggested. The results of the use of a radiopharmaceutical which has not been previously documented in the published literature is discussed.

Electrochemical oxidation of sigma-complex-type intermediates in aromatic nucleophilic substitutions.

A series of sigma-adducts (1H-...7H-) derived from the addition of 2-nitropropenide ion to various nitrobenzofuroxans and nitrobenzofurazans have been oxidized electrochemically. The results show that the rearomatization of the carbocyclic ring of these adducts as well as that of a few additional 4,6-dinitrobenzofuroxan adducts (8 H- a-c) is associated with much higher oxidation potentials than found for the same process in the dinitro- and trinitrobenzene series. Especially high Eo values are measured for the oxidation of the 2-nitropropenide 4,6-dinitro- and 4-nitro-6-trifluoromethylsulfonylbenzofuroxan adducts 1H- and 4H- in acetonitrile: E (1H-)= 1.15 V versus SCE; Eo(4H-)=1.33V versus SCE. These values fit well with the available evidence that the chemical oxidation of these adducts requires the use of very strong oxidizing agents to proceed efficiently. The mechanism for the oxidation process has been established. It is shown to involve transfer of two electrons and liberation of one proton per sigma-complex precursor with no evidence whatsoever for the intermediacy of radical anionic species.

Detection of experimental hepatic tumors using long circulating superparamagnetic particles.

RATIONALE AND OBJECTIVES: To evaluate the potential of an iron oxide-based MR contrast agent for the detection and delineation of experimental liver tumors during the early vascular phase of the compound. METHODS: Superparamagnetic blood pool agent (SBPA) was administered intravenously to rabbits bearing VX2 tumors. Images were acquired before the injection, immediately after, and 1 or 3 weeks later. The variations of signal intensity were measured in the tumors and in several tissues for various T1-weighted spin-echo, T2-weighted fast spin-echo, and T2-weighted gradient-recalled-echo sequences. RESULTS: Fourteen and 12 of the 16 tumors were detected immediately after SBPA injection using, respectively, the T2-weighted fast spin-echo and T2-weighted gradient-recalled-echo sequences. A significant decrease in signal intensity was observed in well-perfused organs, and blood signal was abolished even at the lowest injected dose and using a T1-weighted sequence. In the late phase, the loss in signal intensity of the liver was even more pronounced. CONCLUSION: The dominant T2 effect of SBPA induces an increase in the tumor-to-liver and tumor-to-blood contrast during the vascular phase, improving the detection of the tumors and allowing the distinction between small lesions and vessels through plane. This effect on the liver signal persists for several days because of the incorporation of SBPA in the reticuloendothelial system.

Dual behavior of 4-aza-6-nitrobenzofuroxan. A powerful electrophile in hydration and sigma-complex formation and a potential dienophile or heterodiene in diels-alder type reactions

In investigating the reactivities of aza analogues of super-electrophile 4,6-dinitrobenzofuroxan (DNBF, 1), we have found that the nitro-substituted pyridofuroxan 2 gives a remarkably stable hydrate 3 in aqueous solution (as evidenced by the requirement of ca. 50% H(2)SO(4) (H(0) approximately -3) for complete recovery of 2). The equilibrium constant K(H)()2(O) for hydration of 2 is estimated to be >/= 100, being comparable only with the K(H)()2(O) values reported for hydration of highly activated neutral polyazaaromatics such as 2- and 6-hydroxypteridines or 7-azapteridine. Interestingly, the NH group of 3 undergoes ionization at rather low pH (p = 5.79), affording an anionic hydroxy sigma-adduct 4 which is thermodynamically 10(8) times more stable than the related sigma-adduct of pteridine. The experimental evidence is that 4 is slightly more stable than the hydroxy sigma-adduct of DNBF, indicating not only that 2 ranks among the most electrophilic heteroaromatics known to date but also than an aza group may in fact be as efficient as a nitro group in promoting sigma-complex formation. 2 is also found to be a versatile Diels-Alder reagent, as a result of the low aromatic character of its six-membered ring. Upon treatment of 2 with cyclopentadiene and 2,3-dimethylbutadiene, various reactivity patterns have been observed. These led to different cycloadducts arising from normal as well as inverse electron-demand condensations involving the pyridine ring as the dienophile or the heterodiene contributor. Altogether, the results reveal major differences between the reactivity of 2 and that of DNBF, with in particular a remarkable tendency of the pyridofuroxan adducts to undergo covalent hydration, resulting in the formation of stable carbinolamines. Also noteworthy is the characterization of a diadduct which results from a Diels-Alder trapping of the o-dinitroso intermediate involved in the exchange of the 1-oxide and 3-oxide tautomers of 2.