Cluster of cases due to Shigella flexneri producing CTX-M-15 in Spain

The aim of our study was to delineate an outbreak of gastroenteritis caused by Shigella flexneri and affecting sixteen persons between May and June 2014 in Bilbao, Spain. All patients exhibited symptoms after consuming kebab in the same kebab shop.The outbreak is described through the clinical cases, the microbiological and molecular genetic diagnosis, and the epidemiologic investigation. Minimum inhibitory concentrations for ampicillin, amoxicillin plus clavulanic acid, third and fourth generation cephalosporins, carbapenems, monobactams, aminoglycosides, fluoroquinolones, co-trimoxazole, colistin and tigecycline were measured. The S. flexneri strains were screened by PCR for TEM, SHV, CTX-M beta-lactamases and plasmidic AmpCs and aac(6')-Ib gene. Serotyping, pulsed field gel-electrophoresis, conjugation assay, plasmid sizing by S1 enzyme digestion and Southern blot hybridization were accomplished.All the S. flexneri isolates proved to be serotype 2 and produced extended-spectrum beta-lactamase (ESBL). Carbapenems, fluoroquinolones, tigecycline, colistin, and co-trimoxazole remained active antibiotics. All the strains harboured blaCTX-M-15 and blaOXA-1 genes. The strains hosted two high-molecular weight plasmids of 100 and 230 kb, respectively. According to the hybridization assay blaCTX-M-15 was located on the plasmid of 230 kb. The identical pulsotype verified the presence of outbreak.Remarkable, that one of the food handlers has travelled recently to Pakistan, where ESBL-producing Shigella strains had been reported previously. To the best of our knowledge, this is the first outbreak caused by CTX-M-15-expressing S. flexneri in Spain and as well as in Europe.

11C-Choline PET/CT in the primary diagnosis of prostate cancer: impact on treatment planning

AIM

Aim of the present study was to evaluate the usefulness of 11C-choline PET/CT for detecting lymphatic or haematogenous spread and for planning radiotherapy in patients with medium-to-high risk prostate cancer.

METHODS

We have included 61 consecutive patients recently diagnosed with cancer prostate by biopsy. All patients were classified as medium-to-high risk: Gleason: 7-9; PSA: 6.3-30.4 ng/mL; stage T2c (N.=20) or stage T3 (N.=41). Image acquisition began 5 min after intravenous injection of 11C-choline (656+119 MBq), starting at the pelvis and continuing craniocaudally. Images were interpreted visually to evaluate uptake by the prostate gland. Lymph nodes with 11C-choline uptake were considered invaded, regardless of their size. Bone lesions were considered positive when they showed greater focal uptake than the surrounding bone. In patients with evidence of lymph-node invasion or bone metastases (15 patients), disease was classified as locoregional, oligometastatic, or multimetastatic.

RESULTS

All patients had prostate gland uptake (20 focal, 8 bifocal, and 33 multifocal). Extraprostatic disease was present in 15 patients (24.6%), as follows: 9 (60%) in a single location: in an infradiaphragmatic lymph node (N.=6), in a supradiaphragmatic lymph node (N.=1), and in bone (M1) (N.=2). Six (40%) as multifocal invasion: with both infra- and supradiaphragmatic lymph node involvement (N.=2); with infradiaphragmatic lymph node involvement and M1 bone metastases (N.=3); and infra- and supradiaphragmatic lymph node involvement plus M1 bone metastases (N.=1). Disease was classified as locoregional (N.=6), oligometastatic (N.=5), and multimetastatic (N.=4). The 11 (73.3%) patients with locoregional and oligometastatic disease were selected to undergo intensity-modulated radiation therapy with dose escalation based on the PET findings.

CONCLUSION

Our results suggest that 11C-choline PET/CT is a useful one-stop diagnostic procedure for evaluating patients with medium/high risk prostate cancer scheduled for radical treatment. 11C-choline PET/CT can reliably rule out lymph node involvement and remote metastases, allowing to select candidates for radiotherapy and to plan their treatment.

(11)C-choline PET/CT and multiparametric MRI in patients with biochemical relapse of prostate cancer

CLINIC PROBLEM AND CASE SERIES

To assess the diagnostic usefulness of (11)C-choline PET/CT vs. multi-parametric MRI in the prostate cancer relapse. A retrospective study of 21 patients with prostate cancer treated initially with surgery (n=12), radiotherapy (n=9). PSA levels were increased (post-surgery: .3-3.6 ng/ml; post-radiotherapy: 2.4-8.8 ng/ml). In an interval of time of 15 days all patients were underwent to: whole-body-dual-modality PET-CT carried out early after (11)C-choline (296 ± 29 MBq) injection, and multiparametric prostate MRI with paramagnetic intravenous contrast (using anatomical imaging sequences, diffusion-weighted imaging and dynamic contrast-enhanced imaging). On the basis of our results, all patients were underwent to directed diagnosis and/or clinical, analytic and imaging follow-up. In 15 patients (71.4%) both procedures showed concordant results: 4 negative and 11 positive cases [7 local recurrences, 3 isolated pelvic lymph nodes (2 infracentimetric), 1 local relapse and only one M1 bone metastases]. The results were discordant in 6 patients (28.6%): 3 local relapses in MRI with no PET significance, 1 local relapse in PET with no MRI significance. 2 bone metastases were identified with PET (out of the field-of-view of MRI).

COMMENT

(11)C-choline PET/CT and multi-parametric MRI play a complementary role in the detection of local relapse in prostate cancer patients, with similar sensitivity for the detection of lymph involvement. Whole-body 11C-choline PET/CT technique is also useful for bone staging.

Prevalence of HLA-B*57:01 allele in Argentinean HIV-1 infected patients

Hypersensitivity reaction to abacavir (ABC hypersensitivity syndrome, AHS) is strongly associated with the presence of the HLA-B*57:01 allele. This study was designed to estimate the prevalence of HLA-B*57:01 allele in Argentinean HIV-1 infected patients. We analyzed the presence of HLA-B*57:01 allele in 1646 HIV-1 infected patients from different regions of Argentina. This allele was detected in 81 patients; most of them corresponded to patients living in the central region of the country. The prevalence of HLA-B*57:01 was 4.9%, similar to other Caucasian populations and higher than other data reported for South American populations. This strongly supports screening for the presence of HLA-B*57:01 in abacavir treatment of HIV-1 in our country.

[Diagnostic performance of bone scintigraphy and (11)C-Choline PET/CT in the detection of bone metastases in patients with biochemical recurrence of prostate cancer]

AIM

To compare bone scan (BS) with (11)C-Choline PET/CT for the detection of bone metastases in patients with biochemical recurrence of prostate cancer (PC).

MATERIAL AND METHODS

A total of 169 patients with biochemical recurrence of PC(PSA:2.4-58 ng/ml) who were referred for both exams (0-15 days-in-between) were included. Lesion-detection-rate per patients and lesions were analyzed for both BS and (11)C-Choline PET/CT. Metastasis diagnosis was reached by: biopsy, CT/(18)F-Fluoride PET/MRI confirmation, or evidence of progression in subsequent imaging procedures.

RESULTS

A total of 91 lesions were found to be active in BS and/or (11)C-choline PET/CT (40 patients), with 78 of which were metastatic. BS detected 38 blastic, 2 lytic and 10 non-CT-evident lesions. (11)C-Choline PET/CT detected 41 blastic, 4 lytic and 29 non-CT-evident lesions. BS and (11)C-Choline PET/CT sensitivities were 65.4% and 96.1%; specificities ere 38.5 and 92.3% (χ(2) 8.27, p<0.04). Both imaging techniques were negative in 118 patients. Tracer avid lesions were found in 51 patients: with 30/51 being BS and (11)C-Choline PET/CT concordant; in 21/51 patients had discordant lesions (kappa 0.712, p=0.00). Lesions were absolutely discordant in 10/19 patients,: 5 FN BS, 2 FP BS (degenerative changes; dysplasia), 1 FN (11)C-Choline PET/CT (blastic), 1 FP (11)C-Choline PET/CT (degenerative), 1 out of field-of-view lesion with (11)C-Choline PET/CT (tibia alone). (11)C-Choline PET/CT showed extraosseous involvement in 26/51 patients with bone metastases: 9 local recurrences, 5 infra-diaphragmatic-lymph-nodes, 2 supra-diaphragmatic, 5 local and infra-diaphragmatic, 4 infra- and supra-diaphragmatic, 1 supra-diaphragmatic and lung metastases.

CONCLUSION

(11)C-Choline PET/CT yielded better sensitivity and specificity than BS for the detection of bone involvement in patients with biochemical recurrence of PC and allowed extraosseous restaging, with an impact in the clinical management of these patients.

[Extension study and evaluation of the therapeutic response in a patient with metastatic lung adenocarcinoma using sequential study with ¹⁸F-FDG PET-CT and ¹⁸F-fluoride PET-CT]

We report a case of a patient with lung adenocarcinoma and bone and extraosseus metastases studied with (18)F-FDG PET-CT, (99m)Tc-HMDP and (18)F-fluoride PET-CT. It assesses the usefulness of (18)F-FDG PET-CT for initial staging of the disease and monitoring response to therapy. For the study of the sclerotic bone metastases it shows the superiority of 99mTc-HMDP bone scintigraphy and (18)F-fluoride PET-CT over (18)F-FDG PET-CT, and (18)F-fluoride PET-CT over bone scintigraphy. It also shows the usefulness of (18)F-fluoride PET-CT for monitoring the bone metastases.

[Detection of tumors in the central zone of the prostate with 11C-Choline PET/CT]

Prostate tumors originate 68% in the peripheral region and 24% in the transitional region where tumors originating in the central zone are rare (8%). However, diagnosis of the tumors in the central zone is important since they exhibit greater aggressiveness conditioned by their location and different biological behavior. Magnetic resonance imaging shows problems in identifying lesions in the central prostate zone, since this region has a heterogeneous signal, mainly after the primary treatment. Ultrasound guided sextant biopsy shows a negative result in 28% of prostate tumors. Therefore, it is advisable to repeat or even to perform saturation biopsies. We present two patients, one of them with suspected biochemical prostate cancer and one with biochemical recurrence after radical treatment. In both, (11)C-Choline PET/CT allowed detection of the tumor focus in the central zone of the prostate, with negative complementary diagnostic test and biopsies.

[Detection of second tumors in 11C-choline PET/CT studies performed due to biochemical recurrence of prostate cancer]

Early localization of biochemical recurrence in patients after radical treatment of prostate cancer is a widely accepted clinical indication of (11)C-choline PET/CT. Its widespread clinical use has prompted the depiction of incidentalomas, unusual sites of metastatic lesions, as well as false positive and negative cases. Over the last 6 years, a total of 454 (11)C-choline PET/CT studies have been performed in our institution to locate biochemical recurrence of patients with prostate cancer. With these studies, a second neoplasm has been found in 7 patients (1.54%): 3 lung, 2 colorectal, 1 esophagus and 1 esophageal junction, respectively. Although the clinical usefulness of this technique for detecting cancer lesions other than prostate origin is known for those patients who undergo this technique in the accepted indication, the diagnosis of a second tumor has a significant impact on their therapeutic management.

[Metabolic and osteogenic pattern of prostate cancer bone metastases]

The current protocols include the bone scintigraphy and choline PET/CT to localize recurrence in patients having elevated serum PSA after treatment for prostate cancer. Both methods show good agreement in the diagnosis of bone metastases, however conflicting results can be found. We present three cases in which a PET/CT was performed with (18)F-Fluoride due to disagreement between the bone scintigraphy and (11)C-Choline PET/CT. The (18)F-Fluoride PET/CT was capable of confirming the existence of bone metastasis in all of them, so it may be an alternative to the MRI as a tracer of second bone imaging modality, although its use is limited by cost and availability.

Prognostic significance of surgical margins in transoral CO2 laser microsurgery for T1–T4 pharyngo-laryngeal cancers

Histological affected or close margin is an adverse factor in conventional surgery of larynx-hypopharynx cancer. Our objective was to analyze the relevance of the margins in transoral laser microsurgery (TLM). A retrospective study of 357 consecutive patients with cancer of the larynx and hypopharynx (T1-T4) treated with TLM. Three possible margins were considered: tumor free, affected, and uncertain. An affected margin showed marked tumor infiltration. An uncertain margin was defined when the sample was insufficient, when it showed carbonization impeding accurate evaluation, or when tumor cells were less than 2 mm. Margins were free in 254 (71.1%) patients, affected in 64 (17.9%) and uncertain in 39 (10.9%). One hundred and three patients (28.9%) presented tumor relapse. The margins were associated with tumor relapse (P < 0.001), but were not significantly related to the tumor site (P = 0.307), the pT classification (P = 0.183), or the difficulty of surgical exposure (P = 0.427). Distant metastases were found in 4.7% of the patients with free margins, in 7.7% of those with uncertain margins, and in 14.1% with affected margins. These differences were statistically significant (P = 0.028). Tumor involvement of the surgical margin was associated with higher rates of local relapse, distant metastasis and the necessity of salvage surgery, together with a lower specific actuarial survival rate.

Semen quality in a population of volunteers from the province of Barcelona

A prospective study was carried out on 1005 male volunteers residing in the province of Barcelona. Participants were asked to complete a questionnaire concerning their health status and lifestyle, and provided a semen sample for analysis. Sperm concentration and percentages of motile, and normal forms were evaluated. The effect of smoking, alcohol consumption, stress and previous disease on semen parameters was also evaluated. Normal parameters were found in 22% of volunteers and sperm counts and/or percentage motility below normal threshold values were found in 78%. Asthenozoospermia detected in 62% and oligozoospermia in 17% of volunteers. No statistically significant association was found between semen quality and age, with the exception of a decrease in semen volume (P = 0.04) and progressive motility (P = 0.01). No statistically significant differences in semen parameters were found between smokers and non-smokers or between males who consumed alcohol versus those that did not. However, stress had a negative effect on sperm concentration. In conclusion, the prevalence of normal semen parameters in the study population evaluated was markedly lower than that reported for the general population (60-70%). Since sperm concentration did not appear to decrease with age, the decrease observed in the last decades may be related to exposure to environmental toxicants during the fetal period, as previously suggested.

Bulky cervical liposarcoma associated with sleep apnea syndrome

Sarcomas of the head and neck are relatively infrequent tumors. Liposarcomas represent 10-16% of all soft tissue sarcomas and <5% of them arise from the head and neck. The retropharyngeal area is rarely involved. We present the case of a middle-aged male with clinical symptoms of sleep apnea. A fiber-optic examination revealed a soft submucosal lesion compressing the posterior pharyngeal wall, with partial obstruction of the airway tract. CT showed a large heterogeneous prevertebral mass (6 x 20 cm(2)) occupying the posterior mediastinum. A transoral submucosal biopsy was performed. Histological findings were compatible with a low-grade liposarcoma. The mass was removed in monoblock using a classical laterocervical neck incision. The surgical specimen weighed 500 g. After 24 months of follow-up no signs of tumor recurrence or sleep apnea syndrome were noted.

Delivery of a healthy baby following the transfer of embryos cryopreserved for 13 years

Although embryos can theoretically be frozen for an unlimited period of time, there is still uncertainty about how long embryos can be cryopreserved without compromising pregnancy outcome. Following transfer of fresh embryos obtained after IVF, surplus embryos are usually frozen for personal use in later treatments. A 40-year-old woman was admitted to the centre's embryo adoption programme. She had a 7-year-old son, was diagnosed with ovarian factor infertility and her husband had secretory azoospermia. They underwent two cycles of IVF with donor spermatozoa and one cycle of donor intrauterine insemination that ended in spontaneous abortion. At this point, the couple was admitted to the embryo adoption programme. Six frozen embryos, obtained from a couple that had had a pregnancy through IVF at the centre and that had abandoned their surplus frozen embryos, were assigned to this patient. All six embryos were cryopreserved for 13 years. Of these, three were transferred and the patient became pregnant and delivered a healthy boy. Thanks to the embryo adoption programme, these embryos, rather than being left frozen for an indefinite period of time, were transferred to a couple that was willing to adopt them, resulting in the birth of a healthy newborn.

Prognostic significance of SCC antigen in the serum of patients with head and neck cancer

SCC antigen (Ag) is a tumor-associated Ag (TAA) obtained from squamous cell carcinoma of the uterine cervix. This study reports the evaluation of this TAA in patients with head and neck malignant diseases and its possible prognostic value. Serum samples from 28 patients with benign head and neck diseases from 399 patients with cancer were obtained prior to treatment. SCC Ag serum levels were determined by radioimmunoassay using 2.5 ng/ml as the upper limit of normality. Elevated SCC Ag serum levels were found in 14% of 28 patients with benign diseases, in 29% of 217 patients with primary tumors, in 48% of 46 patients with recurrence (43% in locoregional, 64% in metastases) and in 4% of 136 patients with no evidence of disease. In patients with primary tumors, SCC Ag serum levels were related to nodal involvement and tumor location with significantly higher levels in node-positive patients (p = 0.001) and in tumors located in the nasopharynx and piriform sinus (p = 0.02). Presurgical SCC Ag serum levels in patients with primary tumors had prognostic value with shorter disease-free survival in those patients with abnormal values of this TAA (p < 0.001), in both, node-negative and node-positive patients (p < 0.01). Multivariate analyses showed that SCC Ag is a significant independent predictor of disease-free survival even when other prognostic factors are considered. In conclusion, pretreatment SCC Ag serum levels are an independent prognostic indicator in patients with head and neck malignancies.

Identification of coronary artery disease by 99mTc-MIBI myocardial perfusion single photon emission computed tomography: evaluation using Diamond's method and segmental score system

Three hundred and eighty-one consecutive patients referred to our Nuclear Medicine Service from the Cardiology Department during a period of two years have been studied to evaluate Coronary Artery Disease (CAP) using 99mTc-MIBI single photon emission computed tomography (SPECT). The sensitivity and specificity for detecting CAD in the whole group of patients, referred (n = 161) or not (n = 220) for coronary angiography, were calculated following Diamond's method, and were found to be 87% and 92%, respectively. Diamond's method estimates these values from those obtained in the subset of patients with angiography referral (sensitivity 91% and specificity 85%) and the pattern of SPECT responses of both groups (69% and 52%, respectively). A new segmental score system was used to evaluate the location and extent of CAD in the catheterized group. The sensitivity for detecting individual artery disease was 69% and specificity was 81%. The sensitivity in patients with single, double and triple-vessel disease was 90%, 96% and 89%, respectively. In the subgroup of patients without infarction (n = 66) the sensitivity and specificity were 76% (19/25) and 90% (37/41).

Tc-99m galactosyl-neoglycoalbumin hepatic scintigraphy in fulminant hepatic failure

Tc-99m galactosyl-neoglycoalbumin (NGA) is a new liver imaging agent that specifically binds to a hepatocyte specific membrane receptor, the hepatic binding protein. Scintigraphy with Tc-99m NGA is a noninvasive method that provides functional images of the liver. This report deals with one case of fulminant hepatic failure in which hepatic scintigraphy with Tc-99m NGA predicted hepatic recovery before clinical and biochemical parameters, being a prognostic index in this patient.

Prognostic value of TPS in patients with head and neck malignancies: comparison with SCC

TPS and SCC serum levels were evaluated in 113 patients with primary tumors, 19 with relapse and 59 with no evidence of disease after radical treatment. Abnormal serum levels were found in 37% and 33% of patients with primary untreated tumors and in 53% and 59% of patients with relapse, respectively, using 100 U/L and 2.5 ng/ml as the upper limit of normality for TPS and SCC, respectively. Either tumor marker was abnormal in 57.5% of primary tumors and in 74% of patients with relapse. TPS and SCC serum levels were related to nodal involvement, with significantly higher levels in patients with nodal invasion (p < 0.02 and p 0.001, respectively). No relationship was found between tumor size, age or histological grade and SCC or TPS values. Pretreatment TPS and SCC serum levels had prognostic interest in patients with locoregional tumors, with a significantly shorter disease-free interval (DFI) in patients with abnormal values (p < 0.01 and p < 0.02, respectively). When tumor marker levels and nodes were simultaneously evaluated, a trend toward shorter DFI in patients with abnormal serum concentrations was found, with no statistical significance. By contrast, TPS and SCC were useful in prognosis in node-negative patients (p < 0.02 and p < 0.001, respectively). Likewise, using both TAAs simultaneously, it is possible to increase prognostic information. Patients with TPS and/or SCC abnormal levels had a significantly lower DFI than those patients with normal values, in both node positive and negative patients (P < 0.01). In summary, TPS and SCC are useful TAAs in patients with head and neck malignancies. Likewise, with the simultaneous use of SCC and TPS, the TAA utility in this malignancy increases in the prognosis as well as disease follow-up.

Procedure for red blood cell labelling with 99mTc-HMPAO. Methodology and quality control

We present here results on the labelling of red blood cells with 99mTc-HMPAO as an alternative method to the usual in vitro technique. Anticoagulant agents, the labelling medium with plasma, and the lapse of time between 99mTc-HMPAO preparation and labelling are the main factors which affect the efficiency of the procedure. A 93.9 +/- 2.3% labelling yield was obtained with freshly prepared 99mTc-HMPAO. In vitro (tracer elution of 4.3 +/- 1.2% at 60 mins) and in vivo (percentage of plasma activity at 60 mins, 7.8 +/- 2.8%) stability of the label, as well as image quality, qualify 99mTc-HMPAO labelled red blood cells as a suitable agent for clinical use.