Utilidad clínica de las imágenes de fusión 67Ga SPECT/TC en pacientes con linfoma

AIM

The aim of this work is to show the clinical utility of the fused SPECT 67Ga/CT images in patients with lymphoma.

MATERIAL AND METHOD

44 patients (22 male) with lymphoma have been studied. 22 with Hodgkin's disease and 22 with non Hodgkin lymphoma. 59 studies were performed (33 thorax-cervical [T], 24 abdomen [A] and 2 skull-cervical area [SC]) with an hybrid gammacamera Millenium VG. We acquire consecutively a whole body scan, a SPECT and a CT, for its fusion with the SPECT, of the affects areas. The images were evaluated by two experts blinded, who classify the contribution of the fusion of images respect to the SPECT like: non changes, it improves the location or changes the extension of the injuries and it changes the staging. Final lesion location was confirmed by a high resolution CT performed within one month.

RESULTS

32/59 studies did not change the location or extension of the injuries (20T, 12A), 23/59 studies changed the location or extension of the injuries (12T, 9A and 2 SC) and on 4/59 the change of location induced a change of staging respect to showed by the SPECT.

CONCLUSION

To make fused SPECT 67Ga/CT images in patients with lymphoma allows improving the diagnostic precision in a 46% of the cases, mainly in the abdominal, bone and of the diaphragmatic area studies.

[Tesio twin catheter system for hemodialysis tunnelized using an echo-guided technique. Retrospective analysis of 210 catheters]

PURPOSE

Review a large experience in the placement of tunnelled catheters to assess the outcomes with twin catheter system as hemodialysis access.

MATERIAL AND METHODS

We retrospectively reviewed clinical and hemodialysis data regarding of ESRD patients who were referred from 2 dialysis facilities for placement of tunnelled catheters hemodialysis access between 1996 March and 2005 July. For catheter insertion a real-time sonography technique was used (Site Rite II Dymax corporation) in performing vascular access procedure. The twin catheter system available during the study period consisted of 2 x 10-F12. Patients suspected to present bacteraemia related to catheter were followed with established protocols. Catheter suspected malfunction or thrombosis was treated with low dose Urokinase. To evaluated dialysis dose and adequacy, blood flow rates were recorded and Kt/v calculated by Daugirdas 2nd generation formula.

RESULTS

Overall study period of 112 months, 210 catheters were inserted in 148 patients(93 males and 55 females, mean age 68,6 +/- 4,95 years). 101 catheters were inserted in internal jugular vein, 84 in femoral and 25 in subclavian. The successful insertion rate with only single needle pass was 87.8%, immediate procedural complications rate was 4.7%. The catheters were in place a total of 18,324 days during the study period (mean 87.2 days; range 4-1,280 days). The mean flow blood rate was 252,4 DS +/- 42.4 mL/min, Mean Kt/v was 1,21 DS +/- 0,07. Seventy-seven catheters malfunctioned during study period, in 55 cases urokinase was effective in recovering blood flow rate over 250 mL/min and 25 necessitated removal for ineffective urokinase. Infection incidence was 11.9% with bacteraemia related catheter rate of 2.8 episodes per 1,000 catheter-days, Gram positive bacteria was found in (84%), Gram negative in (12%) and others(4%).

CONCLUSION

Placement of tunnelled twin catheters system using real-time sonography technique can be performed with excellent technical success, safety and acceptable catheter performance and outcomes for effective hemodialysis.

Subdermal re-injection: a method to increase surgical detection of the sentinel node in breast cancer without increasing the false-negative rate

PURPOSE

The aim of this study was to evaluate in breast cancer whether subdermal (SB) re-injection improves surgical detection (SD) of the sentinel node (SN) in patients with negative lymphoscintigraphy on peritumoral (PT) injection, without increasing the false-negative (FN) rate.

METHODS

Group I comprised 261 patients with invasive breast cancer >3 cm and clinically negative axilla treated with primary chemotherapy. Axillary lymphadenectomy was performed in all of these patients. Group IA comprised 201 patients with PT injection, while group IB comprised 60 patients with SB injection in the tumour quadrant. Group II comprised 652 patients with breast cancer <3 cm; in 73 of these patients with negative lymphoscintigraphy, SB re-injection was performed. For lymphoscintigraphy, 37-55 MBq (99m)Tc-albumin nanocolloid in 1 ml was used for PT injection, and 18 MBq in 0.2 ml for SB injection. Five-minute images were obtained 2 h p.i. for PT injection and 20-30 min p.i. for SB injection. SD was performed 4 or 24 h p.i. Lymphoscintigraphic (LD), surgical and internal mammary (IM) detection rates were calculated. In group I, FN, negative predictive value (NPV) and accuracy (A) were calculated. Statistical analysis was performed using the chi-square test.

RESULTS

In percentages, results were as follows: Group IA: SD: 84.1, FN: 13.6, NPV: 88.9, A: 78.6, IM: 14.5*. Group IB: SD: 90, FN: 0, NPV: 100, A: 90, IM: 1.7* (*p<0.025). Group II: PT injection only: LD: 82.4, SD: 94; PT injection+SB re-injection: LD: 90, SD: 98.5. SD was 97.8** in patients with positive lymphoscintigraphy and 58.5** when lymphoscintigraphy was negative (**p<0.001).

CONCLUSION

For correct staging, including extra-axillary drainage, peritumoural injection should first be performed. When the SN is not visualised, and only in those cases, SB re-injection should be performed, which increases the SD rate without increasing the FN rate.

[First diagnostic choice in patients with high clinical suspicion of pulmonary thromboembolism: helical CT or ventilation/perfusion pulmonary scintigraphy?]

AIM

Comparative analysis about helical CT (ThC) vs ventilation-perfusion pulmonary scintigraphy (V/P Sc) diagnosis effectiveness, as a first diagnosis technique in patients with high clinical suspicion of pulmonary thromboembolism (PT).

MATERIALS AND METHODS

Prospective study of 30 patients with high clinical suspicion and high Dimer-D levels (> 250 microg/l). The diagnosis was defined as anticoagulant therapeutic prescription and posterior clinical evolution. V/P Sc were performed to each patient within the next 48 h (an average of 14.8 h) after TCh, without anticoagulant treatment. We classified the scintigrams according to the PIOPED criteria and hTC images as positive, negative and indeterminated.

RESULTS

In sixteen patients final diagnosis was PT: in 9 both techniques were positive; in 5 scintigraphy was positive with normal hTC and in 1, hTC was normal with negative scintigraphy. The last case was an indeterminated hTC with negative scintigraphy. In fourteen patients, final diagnosis was non-PT: in 6 both techniques were negative; in 7 scintigraphy was negative with positive hTC and in 1, both results were indeterminated. The sensitivity, specificity, positive predictive value, negative predictive value and efficiency were respectively 87.5, 100, 100, 87.5 and 93 % for V/P Sc and 62, 50, 58.8, 53.8 and 53 % for TCh.

CONCLUSION

V/P Sc has better PT diagnosis reliability. It is recommended to do V/P Sc in all patients with high clinical suspicion of PT.

High-Q microwave photonic filter with a tuned modulator

We propose the use of tuned electro-optic or electroabsorption external modulators to implement high-quality (high-Q) factor, single-bandpass photonic filters for microwave signals. Using this approach, we experimentally demonstrate a transversal finite impulse response with a Q factor of 237. This is to our knowledge the highest value ever reported for a passive finite impulse-response microwave photonic filter.

Antibodies to carbonic anhydrase and IgG4 levels in idiopathic chronic pancreatitis: relevance for diagnosis of autoimmune pancreatitis

BACKGROUND

Increased serum antibodies against carbonic anhydrase II (CA-II Ab) or IgG4 levels have been reported in cases of autoimmune chronic pancreatitis (ACP).

AIM

To assess the relevance of serum CA-II Ab and IgG4 levels for the diagnosis of ACP in idiopathic CP (ICP) versus alcoholic CP and Sjogren's syndrome (SS).

SUBJECTS

This was a multicentre study involving 227 subjects divided into four groups: ICP (n = 54), normal controls (n = 54, paired by age and sex with ICP patients), alcoholic CP (n = 86), and SS (n = 33).

METHODS

CA-II Ab was measured by ELISA and confirmed by western blotting. A score of easy clinical use with major clinical, morphological, and biochemical parameters for the diagnosis of ACP was applied.

RESULTS

The percentage of patients with increased serum CA-II Ab was higher in the ICP group (28%) than in controls (1.9%) and in patients with alcoholic CP (10.5%), but lower than in patients with SS (64%). The proportion with elevated IgG4 levels was higher in the ICP group (15%) compared with controls (1.9%) and SS (0%) but not significantly different from alcoholic CP (8%). Most ICP patients (7/8) with high IgG4 levels exhibited increased CA-II Ab and a compatible ACP score. A definitive diagnosis of ACP by histological analysis was associated with other autoimmune disorders, an increase in both serum IgG4 and CA-II Ab levels, and IgG4 positive plasma cells.

CONCLUSIONS

The increase in serum IgG4 levels was strongly associated with elevated CA-II Ab levels, manifestations compatible with ACP, and lymphoplasmacytic infiltration when surgical specimens were available.

Tunable and reconfigurable microwave filter by use of a Bragg-grating-based acousto-optic superlattice modulator

We present an all-optical novel configuration for implementing multitap transversal filters by use of a broadband source sliced by fiber Bragg grating arrays generated by propagating an acoustic wave along a strong uniform fiber Bragg grating. The tunability and reconfigurability of the microwave filter are demonstrated.

Comprehensive analysis of the 9p21 region in neuroblastoma suggests a role for genes mapping to 9p21-23 in the biology of favourable stage 4 tumours

Chromosome 9p21 is frequently deleted in many cancers. Previous reports have indicated that 9p21 LOH is an uncommon finding in neuroblastoma (NB), a tumour of childhood. We have performed an extensive analysis of 9p21 and genes located in this region (cyclin-dependent kinase inhibitor 2A – CDKN2A/p16^INK4a, CDKN2A/p14^ARF, CDKN2B/p15^INK4b, MTAP, interferon α and β cluster). LOH was detected in 16.4% of 177 NB. The SRO was identified between markers D9S1751 and D9S254, at 9p21–23, a region telomeric to the CDKN2A and MTAP genes. A significantly better overall and progression-free survival was detected in stage 4 patients displaying 9p21–23 LOH. Hemizygous deletion of the region harbouring the CDKN2A and CDKN2B loci was identified in two tumours by means of fluorescent in situ hybridisation and MTAP was present by immunostaining in all but one tumour analysed. The transcriptional profile of tumours with 9p21–23 LOH was compared to that of NB displaying normal 9p21–23 status by means of oligonucleotide microarrays. Four of the 363 probe sets downregulated in tumours with 9p21–23 LOH were encoded by genes mapping to 9p22–24. The only well-characterised transcript among them was nuclear factor I-B3. Our results suggest a role for genes located telomeric of 9p21 in good risk NB.

Complete sequence of the genome of the human isolate of Andes virus CHI-7913: comparative sequence and protein structure analysis

We report here the complete genomic sequence of the Chilean human isolate of Andes virus CHI-7913. The S, M, and L genome segment sequences of this isolate are 1,802, 3,641 and 6,466 bases in length, with an overall GC content of 38.7%. These genome segments code for a nucleocapsid protein of 428 amino acids, a glycoprotein precursor protein of 1,138 amino acids and a RNA-dependent RNA polymerase of 2,152 amino acids. In addition, the genome also has other ORFs coding for putative proteins of 34 to 103 amino acids. The encoded proteins have greater than 98% overall similarity with the proteins of Andes virus isolates AH-1 and Chile R123. Among other sequenced Hantavirus, CHI-7913 is more closely related to Sin Nombre virus, with an overall protein similarity of 92%. The characteristics of the encoded proteins of this isolate, such as hydrophobic domains, glycosylation sites, and conserved amino acid motifs shared with other Hantavirus and other members of the Bunyaviridae family, are identified and discussed.

Estudio de cea y cyfra 21.1 pre-tratamiento en 252 pacientes con carcinoma de cabeza y cuello

INTRODUCTION

Squamous cell carcinoma is the most frequent malignant tumor in the head and neck. As in most malignant tumors, the earlier the diagnosis, is made the longer the survivalis. Several molecules, including CEA and Cyfra 21.1, have been evaluated in an attempt to improve diagnosis and follow-up.

OBJECTIVE

To investigate whether CEA and Cyfra 21.1 present pathological increased values prior to treatment, and to correlate tumor and patient characteristics with CEA and Cyfra 21.1 levels.

MATERIAL AND METHODS

CEA and Cyfra 21.1 were measured pre-treatment in sera of 252 patients treated for head and neck tumors from1999 to 2003.

RESULTS

Increases of CEA were detected in 23.6%, and increases of Cyfra 21.1 in 19.1% of patients. Significative differences were found between the concentrations of Cyfra 21.1 related to the tumor stage, local extension, histological grade, and an increasing relation with age. No differences were found in relation to the primary tumor site. Regarding CEA, the only finding was an increased relation between concentrations of this marker and cigarette and alcohol habits.

CONCLUSIONS

Cyfra 21.1 does not appear to be a good marker for tumoral screening of head and neck carcinomas. However, a good correlation was observed between sera concentrations of Cyfra 21.1, tumoral burden, and histological grade of the tumor, but this was not the case with CEA.

Tunable all-optical negative multitap microwave filters based on uniform fiber Bragg gratings

We present a novel and simple technique for obtaining transversal filters with negative coefficients by using uniform fiber Bragg gratings. We demonstrate a wide tuning range, good performance, low cost, and easy implementation of multitap filters in an all-optical passive configuration in which negative taps are obtained by use of the transmission of a broadband source through uniform Bragg gratings.

Clinical usefulness of KRAS mutational analysis in the diagnosis of pancreatic adenocarcinoma by means of endosonography-guided fine-needle aspiration biopsy

AIM

To establish the usefulness of KRAS mutational analysis in the diagnosis of pancreatic adenocarcinoma by comparing this technique with conventional cytology in aspirates obtained by endosonography-guided fine-needle aspiration.

METHODS

All consecutive patients with pancreatic focal lesions undergoing endosonography-guided fine-needle aspiration were included. Samples were obtained with the concurrence of an attendant cytopathologist. Detection of codon-12 KRAS mutations was performed by the restriction fragment length polymorphism-polymerase chain reaction method. The effectiveness of conventional cytology, KRAS mutational analysis and their combination was established with respect to the definitive diagnosis. A cost-effectiveness analysis was also performed.

RESULTS

Thirty-three patients had pancreatic adenocarcinoma and 24 patients had other lesions. A total of 136 samples was obtained. In patients in whom specimens were adequate (93% for cytology; 100% for mutational analysis), the specificity of both techniques was 100%, whereas the sensitivity favoured cytology (97% vs. 73%). When inadequate samples were considered as misdiagnosed, a combination of both techniques reached the highest overall accuracy (cytology, 91%; mutational analysis, 84%; combination of both, 98%).

CONCLUSIONS

Cytology from aspirates obtained by endosonography-guided fine-needle aspiration is the most precise single technique for the diagnosis of pancreatic adenocarcinoma. However, when adequate specimens are not available to reach a cytological diagnosis, the addition of KRAS mutational analysis represents the best strategy.

[Neurological explorations in Nuclear Medicine. A Spanish survey]

A representative Nuclear Medicine Service in Spain has two or three gammacameras. It performs neurologic studies one or two days at week wich account 2,1% of total workload. Brain Perfusion SPECT, specially in cognitive disorders, is the most frequent application. Neurooncology has a lower but established relevance. Neuroreceptors imaging are increasing in the last months. Emission tomography is obtained using a double-headed camera fitted with high-resolution parallel hole collimators and a half an hour total acquisition time. Datasets are reconstructed by filtered backprojection with Butterworth or Metz filtres. Images are visually interpreted with comparison to MRI and/or CT findings.

A system for the direct determination of the nonvolatile organic carbon, dissolved organic carbon, and inorganic carbon in water samples through inductively coupled plasma atomic emission spectrometry

A new system has been developed for the determination of total organic carbon (TOC) and inorganic carbon (IC) or total inorganic carbon (TIC) in waters. Only nonvolatile organic compounds can be detected through the present method. The system presented in this work is based on the measurement of the carbon atomic emission intensity in inductively coupled plasma atomic emission spectrometry (ICP-AES). This way, the organic matter does not undergo any preoxidation step. A semiautomatic accessory connected to the spectrometer separates the different carbon fractions (i.e., organic and inorganic). Because most of the solutions used in the present work did not contain suspended solid particles, the actual parameter that was determined was the dissolved organic carbon (DOC). The present system exhibits good sensitivities compared to those provided by conventional TOC and IC determination methods. The limits of detection obtained in the present work have been 0.07 and 0.0007 mg/L C in terms of TOC and IC, respectively. Furthermore, the system is able to handle high-salt-content solutions. This fact suggests that it would be possible to analyze seawater samples, avoiding some of the problems encountered with conventional methods, such as system blocking or interferences. The TOC and IC values found for natural samples are very close to those measured using conventional methods. The ICP-AES method has been successfully used in two interesting applications: (i) monitoring the efficiency of a water treatment plant and (ii) determining the contents of dissolved carbon dioxide, on one hand, and that of carbonate and bicarbonate, on the other, in the same sample.

[Endoscopic treatment of pancreatitis and its complications]

OBJECTIVES

To study the long- and short-term safety and efficacy of endoscopic treatment of pancreatitis and its complications in our environment.

PATIENTS AND METHODS

We performed a retrospective analysis of 43 patients with chronic pancreatitis, acute pancreatitis complicated with pseudocyst, and pancreatic fistula diagnosed by endoscopic retrograde cholangiopancreatography who were suitable for endoscopic treatment.

RESULTS

Endoscopic treatment was attempted in 35 patients. The indication for treatment was pain in 17 patients (48.5%), jaundice in 7 (20%), pseudocyst in 10 (28.5%) and suspected external fistula in 1 (3%). The technique was successfully performed in 28 (80%). Of the patients with pain, pancreatic prosthesis was inserted in 13 and extracorporeal lithotripsy was applied in 6. Sixty-five percent of the patients improved. Of the 7 patients with jaundice, all had secondary stenosis of the biliary tract. Treatment was applied in 2, who showed partial improvement. Of the 15 patients with pseudocyst, endoscopic treatment was indicated in 10; the technique was successfully performed in 8 and complete resolution was achieved in 7 (87.5%). The patient with external fistula was treated with transpapillary prosthesis and complete resolution of disruption of Wirsung's duct was achieved. Overall improvement in successfully treated patients was: complete in 19 (68%), partial in 3 (18%), no improvement in 4 (14%) and 2 patients were lost to treatment. There were 4 short-term complications. There were 4 deaths and one was related to the technique.

CONCLUSIONS

Endoscopic treatment of chronic pain in chronic pancreatitis, pseudocysts and fistulas was effective in our environment with a low rate of complications.

Fanconi anemia and primary cataracts: first case

Fanconi anemia or pancytopenia is an autosomal recessive condition presenting with a combination of pancytopenia with a mean age of onset of about eight years, a tendency to leukemia, and congenital anomalies. Although ocular abnormalities have been described, cataracts have not been previously reported. We present a patient with proven Fanconi anemia and cataracts.

[Endoscopic treatment combined with extracorporeal shock wave lithotripsy of difficult bile duct stones]

OBJECTIVES

The aim of this study was to determine the safety and effectiveness of extracorporeal shock wave lithotripsy (ESWL) in difficult bile duct stones resistant to endoscopic extraction.

PATIENTS AND METHOD

From January 1997 to February 2002, combined treatment with endoscopy and ESWL was used in 19 patients who had undergone unsuccessful endoscopic bile duct stone extraction after sphincterotomy. The procedure was carried out using analgesic and sedative drugs or deep sedation, prophylactic antibiotic therapy, and monitoring of vital signs. Bile duct stone localization was performed by contrast injection through nasobiliary drainage and fluoroscopy. After each ESWL session, lavage was performed through drainage and stone fragments were extracted endoscopically.

RESULTS

The 19 patients presented high surgical risk due to advanced aged and/or concomitant diseases. All presented jaundice and pain and nine (47.3%) presented associated cholangitis. Thirty ESWL sessions were performed (1.57 sessions per patient), with a mean of 2,120 shock waves per session. In 16 of the 19 patients (84.2%), combined treatment with ESWL and subsequent instrumental endoscopic extraction achieved complete clearance of the biliary tract. The treatment failed in 3 patients who were referred for surgical treatment. No early or late complications were observed, except in one patient who presented a self-limiting febrile syndrome.

CONCLUSIONS

Therapeutic endoscopy combined with ESWL is safe and effective in patients with difficult bile duct stones. It represents a therapeutic alternative in patients at high surgical risk.

Automatic tunable and reconfigurable fiberoptic microwave filters based on a broadband optical source sliced by uniform fiber Bragg gratings

We demonstrate an automatic tunable transversal notch filter based on uniform fiber Bragg gratings and a broadband optical source. High tunability can be performed by stretching the fiber with the gratings written in series. Also, high sidelobe supression can be achieved by introducing tunable attenuators in a parallel configuration of the gratings.

First human isolate of Hantavirus (Andes virus) in the Americas

We isolated Andes virus (formal name: Andes virus [ANDV], a species in the genus Hantavirus), from serum of an asymptomatic 10-year-old Chilean boy who died 6 days later of hantavirus pulmonary syndrome (HPS). The serum was obtained 12 days after his grandmother died from HPS and 2 days before he became febrile. No hantavirus immunoglobulin (Ig) G or IgM antibodies were detected in the serum sample. After three blind passages, ANDV antigens were detected in Vero E6 cells by immunofluorescence assay and enzyme-linked immunosorbent assay, and ANDV RNA was detected by reverse transcription-polymerase chain reaction. A fragment of the virus genome showed 96.2% nucleotide identity with that of prototype ANDV. To our knowledge, this is the first isolation of any agent of hemorrhagic fever with HPS from a human and the first such isolation of hantavirus before symptoms of that syndrome or HPS began.