[An emerging problem: heteroresistance in Mycobacterium tuberculosis]

Mixed infection by Mycobacterium tuberculosis (Mtb) consists in the simultaneous coexistence in the same patient of two different strains of Mtb or 2 different variants of the same strain. When one of the variants selects for resistance mutations, it is called monoclonal heteroresistance (HTR); if there are 2 different strains, one sensitive and one resistant (or with different resistance patterns), it is called polyclonal HTR. Three cases of HIV/AIDS patients are presented, all with repeated treatment adherence problems, in whom monoclonal HTR was diagnosed through Mtb complete genomic sequentiation with the coexistence of two variants of the same strain isolated from samples from lung and lymph nodes, with different resistance profiles in each case. It is important to consider the possibility of HTR, especially in patients with multiple previous therapeutic attempts and high bacillary populations, such as in advanced AIDS, since this situation potentially compromises treatment results by coexisting sensitive and resistant variants of a strain (or strains).

POS1285 IMMUNOGENICITY AND SAFETY OF THE CHADOX 1 COVID-19 VACCINE IN PATIENTS WITH AUTOIMMUNE DISEASES AND HEALTHY CONTROLS: DATA FROM SAFER STUDY

Background

Patients with autoimmune inflammatory diseases (AID) have been prioritized for urgent vaccination to mitigate COVID-19 risk. However, few studies in the literature assessed the immunogenicity and safety of the COVID-19 vaccine in patients with AID.

Objectives

In this context, the present study aims to evaluate the immunogenicity and safety of the vaccine against COVID-19 in patients with AID.

Methods

These data are from “Safety and efficacy on COVID-19 Vaccine in Rheumatic Disease” - SAFER study, a Brazilian multicentric prospective phase IV study to evaluate COVID-19 Vaccine in AID, in the real-life, in Brazil. Immunogenicity and adverse events (AE) from a single center were assessed, after 2 doses of ChAdOx1 (Oxford/AstraZeneca), 8 weeks of interval, in patients with AID and healthy controls (HC). Inclusion criteria were age ≥ 18 years and fulfilling criteria according to international classification for AID. Exclusion criteria: pregnancy, previous severe AE to any vaccine, other immunosuppression causes. Stratification of post-vaccination AE was performed using a diary, filled out daily and returned at the end of 28 days for each dose. Participants were followed up through blood collection for measurement of IgG antibodies against SARS-CoV-2 spike receptor-binding domain by chemiluminescence (SARS-CoV-2 IgG II Quant assay, Abbott Laboratories, Abbott Park, IL, USA) at baseline and 28 days after the second dose. The seropositivity was defined for titers ≥50 AU/mL. Quantitative analyses were presented as observed frequency, percentage, central tendency, and variability measurements. The sample’s normal distribution was verified through the Shapiro-Wilk test. The Kruskal-Wallis test and the post-hoc Dwass-Steel-Critchlow-Fligner pairwise comparisons test were used to compare the IgG-S titers between the groups through the evaluation period. Categorical data were addressed using the Fisher´s exact or Chi-squared (χ2) test. An alpha level of 5% significance was used in all analyses.

Results

A total of 377 volunteers with AID and 50 HC were included in the study. Patients with spondyloarthritis (N=64), systemic lupus erythematosus (N=63), rheumatoid arthritis (N=61), primary Sjögren’s syndrome (N=61), vasculitis (N=31), systemic sclerosis (N=14), inflammatory myopathy (N=9), Crohn´s disease (N=49), ulcerative colitis (N=11) and other systemics AID (N=12) were evaluated. Both groups had female predominance (73.5% vs. 74.0%, p=0.937) and were homogeneous for age (43.5 vs. 41.7,p=0.308). The seroconversion among those not reactive (IgG-S negative at baseline) (46 HC and 191 AID), 28 days after second dose was 97.1% for spondyloarthritis (p=0.425), systemic lupus erythematosus 88.2% (0.006), rheumatoid arthritis 93.5% (0.158), primary Sjögren’s syndrome 92.6% (0.133), systemic sclerosis or inflammatory myopathy 47.1% (0.001), inflammatory bowel disease 100% (0.999) and vasculitis 80% (0.006), while in healthy control was 100%. In comparison with HC, there was a statistically significant difference in IgG-S titles only in systemic sclerosis or inflammatory myopathy (1.694 AU/ml vs. 3.719 AU/ml; p=0.006). Both groups only presented mild AE. Pain at the injection (85.7% vs. 78.4%, p=0.239), headache (67.3% vs. 53.8, p=0.074) and fatigue (59.2% Vs. 46.2%, p=0.089) were more common in HC than AID. Overall, reactions like arthralgia (52.6 vs. 22.4%, p<0.001), hematoma (14.1 vs. 4.1%, p=0.05), cutaneous rash (9.5 vs. 0%, p=0.024) were more frequent in AID. Most participants related that they felt safer after receiving a COVID-19 vaccination, and 52.4% did not reported a worse patient global assessment (PGA) index.

Conclusion

In conclusion, our data indicated that ChAdOx1 vaccine is safe and induced high titers and seroconversion rate in AID. More severe AID, such as vasculitis, systemic lupus erythematosous, and systemic sclerosis and myositis showed a lower seroconversion rate. Further analysis will explore the association between immunossupressant and reactivity, and booster dose.

Acknowledgements

Acknowledgements to DECIT/MS and ICEPI/SESA for supporting the study.

Disclosure of Interests

None declared

Revisiting Polymer-Particle Interaction in PEO Solutions

We have measured the electrophoretic mobility and diffusion coefficient of carboxylate-modified and sulfate-modified polystyrene latex particles in poly(ethylene oxide) aqueous solutions. Carboxylate-modified polystyrene particles have shown a bound polymeric layer as the surface net charge vanishes even at very low poly(ethylene oxide) concentration. The polymeric layer causes a lower electrophoretic mobility and slower Brownian diffusion than that corresponding to the bare particles. We show that the diffusion is the result of a significantly increased effective particle size 2r_heff = 30 nm. This bound layer is not present in sulfate-modified polystyrene latex particles. The interaction between the carboxylate-modified particle surface and the macromolecules has been confirmed by means of atomistic computer simulations. The grafted acrylate copolymers, which come from the preparation procedure of the latex particles, confer more hydrophobic surface ready to interact with the polymer. The simulations suggest that the interaction is modulated not only by the nature of the acrylic acid monomer but also by the length of the grafted copolymer. Our results have important implications for particle selection in microrheology experiments.

Cervical cancer screening information flow in Northern regional administrative service in Portugal

Management of a population-based screening program circuit depends on characteristics and technical barriers of its application and implementation. The aim is to clarify the information flow, to understand and build a vision of cervical screening information flows in Northern Regional Health Administration Portuguese Public System and to identify the constraints among them. A total of 5 cluster meetings were presented and two expert interviews were conducted allowing to present an informational flow and its constraints. Aims addressed in each interview where based on the expertise of the interviewed. Cervical cancer screening program depends on the use of SiiMA application. This is an information system for the management of population-based screening program which involves mainly 3 entities and allows a longitudinal data collection and study. Three main constraints were reported. The time for updating data for the list of eligible women was bigger than accorded reaching up to 3 months delay. A duplicate of records and discharges in hospital care since the discharge was done both in the hospital system and the SiiMA platform manually in order to the woman re-enter the screening program. Pendencies were seen due to other screening programs running in parallel which had to be sorted out manually in the regional level or by the entity involved. The existence of a screening application is vital for the implementation purposes of a screening program. The lack of integration of the systems increases bureaucratic work, costs and causes time delay. To improve the efficiency of digital transformation ensuring the quality of the process it is necessary to adapt the design of the health informatic systems to the daily practice and its wants and needs. The strategies of forcing an ever-increasing number of frameworks have demonstrated not to be so effective. Therefore, it is a cornerstone to understand these flows in order to improve its structure, intervention and optimization.

Key messages

The existence of a screening digital application is vital but its expanding use arises constraints. Due to the complexity of such programs, a digital strategy is crucial for management and monitoring of the screening at this scale.

[Does Ecuadorians with asthma has preferences in the use of information and communication technologies? Pilot study]

BACKGROUND

Inadequate communication between asthmatic patients and their physicians may interfere directly with asthma control. In the last years, the use of information and communication technologies (ICTs) it has increased in Latin-America. This technology seems to be a good tool to improve communication and management of the asthmatic patient.

OBJECTIVE

We evaluated the frequency and preference patterns of communication and information technologies in Ecuadorian patients with bronchial asthma.

METHODS

We conducted a pilot cross-sectional study to identify the frequency and preferences of ICT in patients with asthma. The Spanish version of the Michigan questionnaire was used. Age and educational level were categorized into 3 groups. We used logistic regression between these groups regarding the frequency of use, interest in seeking and receiving information related to their asthma for the age and educational level of the patients.

RESULTS

A total of 222 patients participated in our study. The mean age was 45.6 years (SD 17.4), the most common sex was female with 89.25 %. Almost all patients had a cell phone (87.5 %) and internet access (62.7 %). The three ICTs most likely to be used to search for or receive information about their illness were WhatsApp, Facebook and email (p <0.05).

CONCLUSION

Information and communication technologies improve the care of asthmatic patients. In our pilot study email and text messages are the most preferred ICT among patients however WhatsApp and Facebook may be appropriate for certain ages especially young asthmatic. Knowledge of preferences can help the development of ICT in a personalized way and improve the outcomes in patients with asthma.

Myrciaria dubia "camu camu" flour as a magnetoprotector in male mouse infertility

Possible adverse effects of extremely low frequency magnetic fields (ELF-MF) are linked to a decrease of antioxidant defenses and the production of free radicals. The increase of free radicals affects the mitochondrial functionality inducing apoptosis, which affects the phosphorylation and generation of key ATP in fertilization. Myrciaria dubia, known as "camu camu," is a fruit with high levels of ascorbic acid, which exerts an important antioxidant function in the prevention of premature cell damage. In this study, the effect of Myrciaria dubia flour on oxidative damage produced by ELF-MF (610 μT) was evaluated by detecting the activity of endogenous mitochondrial oxidoreductase enzymes in a complete sperm cycle of mice. We found that the MF caused a significant (P < 0.05) decrease in sperm quality, whereas the groups supplied with Myrciaria dubia flour (50 and 75 mg/kg of body mass) in ELF-MF exposure showed a significant recovery (P < 0.05) in parameters of viability, percentage of plasma membrane integrity and mitochondrial activity, and index of epidymal sperm. This suggests that Myrciaria dubia flour would have an antioxidant activity that counteracts the damaging effects of ELF-MF in spermatogenesis and could be used as a natural ELF-MF protector. Bioelectromagnetics. 40:91-103, 2019. © 2019 Bioelectromagnetics Society.

[Job's syndrome and miliary tuberculosis]

The hyper Immunoglobulin E syndrome, also known as Job's syndrome, is a rare primary immunodeficiency, its mechanisms of inheritance maybe recessive or dominant autosomal. It is characterized by high levels of IgE, eosinophilia, skin abscesses, eczema, chronic mucocutaneous candidiasis and recurrent pulmonary infections all of which contribute to the development of pneumatoceles and bronchiectasis. The most frequently isolated bacteria is Staphylococcus aureus. Currently, despite the highest survival of patients, lymphomas and other opportunistic infections have been reported. There are few reports of patients with Mycobacterium tuberculosis infection associated with hyper IgE syndrome. Therefore it is relevant that we report a case history of a patient with pulmonary tuberculosis, presenting miliary tuberculosis and severe respiratory compromise, who responded positively to standard anti-tuberculous treatment with first line drugs.

Características del crecimiento y desarrollo fetal en hiperémesis gravídica

Introducción: La hiperémesis gravídica (HG) cursa con restricción del crecimiento intrauterino (RCIU) y peso bajo al nacer. Objetivos: Determinar en gestante con HG las curvas de crecimiento fetal por ecografía (CCF) y peso al nacer (PAN). Diseño: Descriptivo, prospectivo. Institución: Hospitalización y consultorio de endocrinología, Instituto Nacional Materno Perinatal (INMP). Participantes: Gestantes con HG y sus recién nacidos (RN). Intervenciones: En los recién nacidos (RN) de 45 gestantes con diagnóstico de HG, se obtuvo antropometría del RN (peso, talla) y CCF. Se consideró RCIU al peso fetal estimado por biometría por debajo del percentil 10 en la curva de crecimiento fetal; macrosomía, al peso al nacer de 4 kilos o mayor; peso bajo al nacer, al peso menor de 2,5 kilos. Principales medidas de resultados: Características de gestantes y de los recién nacidos. Resultados: Promedios maternos: edad gestacional 10,7 semanas, edad 24,5 años, ganancia de peso durante la gestación 12,2 kg, parto a las 38,8 semanas. Promedios de los RN: peso 3 430,5 g (dos macrosómicos), talla 50,2 cm. Nacimiento de los niños en Lima 66,7%, sierra 22,3%, costa no Lima 6,6%, selva 4,4%; parto en el INMP 31,1% (14); primigestas 57%, secundigestas 28,5% tercigestas 14,5%, parto eutócico 50% (nueve RN femeninos, cinco masculinos), ápgar a los 5 minutos 92%. No hubo peso menor de 2 500 g ni RCIU. Conclusiones: La hiperémesis gravídica en el Instituto Nacional Materno Perinatal no se relacionó con peso bajo al nacer o con restricción del crecimiento intrauterino. Hubo 2 macrosómicos.

[Adverse drug reactions in multidrug-resistant tuberculosis]

Multidrug-resistant tuberculosis (MDRTB) poses difficulties in diagnosis and treatment, including increased frequency of adverse reactions to antituberculosis drugs (ADRAs), which compromise the effectiveness of treatment. This is specially complicated in the treatment of patients co-infected with HIV which includes the antiretroviral therapy plus the treatment of eventual comorbidities. A total of 121 MDRTB patients, 87 HIV-negative and 34 HIV positive, assisted in the Hospital F. J. Muñiz, Buenos Aires, during the period 2003-2007 were retrospectively studied. The incidence of ADRAs among the two groups of patients was compared. All the patients with adherence to treatment (no more than one abandon, recovered) were included in the study. Antituberculosis drugs used were: ethambutol, pyrazinamide, ofloxacin, moxifloxacin, cycloserine, ethionamide, PAS, streptomycin, kanamycin, amikacin and linezolid. The emergence of ADRAs and the proportion of severe reactions attributed to antituberculosis drugs were similar in both groups: 44.8% in HIV negative and 44.1% in HIV positive, but it was observed an additional 23.5% of adverse reactions to antiretroviral therapy in the second group. There were differences in the type of reactions and time of occurrence between the two groups. One HIV positive patient died of epidermolysis. The proportion of adverse reactions in HIV/AIDS patients increased 50% when those attributed to antiretroviral treatment were included. We conclude that the studied population showed a frequency of ADRAs higher than it would be expected in the treatment of susceptible TB, but there was no difference in its frequency among HIV-negative and positive patients.

A population-based study of drug resistance and transmission of tuberculosis in an urban community

SETTING

A low-income neighborhood of Sao Paulo, Brazil.

OBJECTIVE

To determine the incidence, risk factors and transmission patterns of multidrug-resistant tuberculosis (MDR-TB).

DESIGN

Prospective longitudinal study of patients with pulmonary TB (PTB).

METHODS

Sputum culture-confirmed patients with PTB were recruited between March 2000 and May 2002. Bivariate and multivariate logistic regression analyses were performed to identify factors associated with MDR-TB. Mycobacterium tuberculosis isolates were tested for drug susceptibility and typed by IS6110-RFLP analysis.

RESULTS

Of 420 patients, respectively 71% and 27% were new and previously treated; 15.5% of the patients' M. tuberculosis isolates were resistant to at least one drug; of these, 11% and 27% were found among new and previously treated cases, respectively. Respectively 1% and 16.7% of the new and previously treated cases were MDR-TB. RFLP analysis showed that new transmission of MDR strains was uncommon. By multivariate logistic regression analysis, previous TB and hospitalization in the 24 months before TB diagnosis were identified as independent predictors of MDR-TB.

CONCLUSIONS

The results showed an intermediate level of MDR-TB incidence in a neighborhood of Sao Paulo and identified predictors that can be targeted for intervention by national and local TB control programs.

Structure of bacteriocin AS-48: from soluble state to membrane bound state

The bacteriocin AS-48 is a membrane-interacting peptide, which displays a broad anti-microbial spectrum against Gram-positive and Gram-negative bacteria. The NMR structure of AS-48 at pH 3 has been solved. The analysis of this structure suggests that the mechanism of AS-48 anti-bacterial activity involves the accumulation of positively charged molecules at the membrane surface leading to a disruption of the membrane potential. Here, we report the high-resolution crystal structure of AS-48 and sedimentation equilibrium experiments showing that this bacteriocin is able to adopt different oligomeric structures according to the physicochemical environment. The analysis of these structures suggests a mechanism for molecular function of AS-48 involving a transition from a water-soluble form to a membrane-bound state upon membrane binding.

Management of carotid coils during routine carotid endarterectomy

BACKGROUND

A coil in the internal carotid artery (ICA), defined as a circular configuration or exaggerated S shape of the ICA, is occasionally encountered during endarterectomy for carotid bifurcation lesions. The significance of coils as an etiology for symptoms is difficult to determine. It is thought, however, that the failure to correct coils and kinks during routine carotid endarterectomy (CE) may lead to turbulence and failure of the CE. Various techniques have been discussed to repair coils.

METHODS

Our technique consisted of complete dissection of the coil, routine use of a Javid shunt, standard endarterectomy, resection of the redundant ICA, re-approximation of the posterior wall of the ICA and patch angioplasty of the anterior wall. Three hundred and fifteen patients underwent CE between August, 1998 and February, 2000. Fifteen patients (4.7%) had a carotid coil that was repaired. There were ten men and five women. Mean age was 72.6+/-6.1 years. Ten patients had an asymptomatic stenosis. Four patients had lateralizing symptoms and one patient had dizziness. Fifteen patients underwent preoperative duplex scanning and 14 of these patients had MRA scans performed. All patients had a preoperative stenosis of 80-99% by duplex on the operated side. The right carotid artery was repaired in 12 patients. The left in three patients. The length of resected artery varied from 1.2-2.8 cm (1.93+/-0.49 cm).

RESULTS

All patients survived surgery. One patient developed a cerebellar stroke on the third postoperative day. A postoperative carotid duplex scan demonstrated a widely patent repair. There were no cranial nerve injuries in this series. One patient died seven months after surgery from cardiac events with no follow-up duplex exam. There have been no long term strokes or anastomotic complications. Follow-up duplex scans demonstrated widely patent repairs (1-15% stenosis) in seven patients and low end 15-49% stenosis in five patients.

CONCLUSIONS

Resection of redundant ICA with re-anastomosis of the posterior wall and patch reconstruction of the anterior wall gives acceptable perioperative and long term results.

Thyroid hormones and cytogenetic outcomes in backpack sprayers using ethylenebis(dithiocarbamate) (EBDC) fungicides in Mexico

Ethylenebis(dithiocarbamate) (EBDC) fungicides are used heavily in the United States. EBDCs (e.g., mancozeb, maneb) are metabolized to ethylene thiourea (ETU). The EPA classifies ETU as a carcinogen, based on thyroid and other cancers in rodents, and has restricted the use of EBDCs, while requiring workers to use protective equipment. There are no data on the potential carcinogenicity of EBDCs in humans, and there is only one study on human genotoxicity. ETU is known to cause decreases of thyroxine (T4) and increases in thyroid-stimulating hormone (TSH) in rodents. We have studied cytogenetic outcomes and serum thyroid hormone levels among 49 heavily exposed workers without protective equipment spraying EBDC on tomatoes in Mexico. We also studied 14 lightly exposed landowners and 31 nonexposed controls. Urinary ETU was used to compare exposure between groups. We found an increase in TSH (p = 0.05) among applicators compared to controls, but no decrease in thyroid hormone (T4). We found increases in sister chromatid exchange (p = 0.03) and in chromosome translocations (chromosome aberrations that persist through cell division) for applicators compared to controls (p = 0.05). However, the subset of reciprocal translocations showed a lesser increase (p = 0.24). Our data suggest that EBDCs affect the thyroid gland and the lymphocyte genome among heavily exposed workers. However, our data are limited to subclinical outcomes, are of borderline statistical significance, and should be interpreted with caution.

Research-based practice: reducing restraints in an acute care setting--phase I

The purpose of this research utilization project was to select and implement a research-based Restraint Education Program for reducing the use of restraints in an acute care setting by changing the perception of the restraint coordinators about restraints in the direction of decreased importance. The Iowa Model, Research Based Practice to Promote Quality Care (Titler et al., 1994) was selected to guide the change process. A multidisciplinary team reviewed the restraint policy and procedure, new restraint products and alternative restraint methods. After a review of the literature on restraint education programs, the committee concluded that education was the key component in decreasing the use of physical restraints. The research-based Restraint Education Program developed by Drs. Strumpf and Evans was selected as the educational program. Education sessions were developed and a pilot study was conducted with the restraint coordinators. The Perceptions of Restraint Use Questionnaire (PRUQ) (Strumpf & Evans, 1988) was administered before and after the education sessions. The results of the t-test showed a decrease in the post-test mean scores on 7 of the 17 items indicating a less important perception by the staff about the use of restraints. Four items had an increase in mean scores on the post-test indicating the restraint coordinators increased their perception of the importance of physical restraints with these items. The restraint education program was presented to the nursing staff throughout the institution. Risk management and quality assurance will monitor patients restrained and evaluate the nursing staff with the PRUQ in 3 months.

Exposure assessment for workers applying DDT to control malaria in Veracruz, Mexico

DDT has systematically been used in sanitation campaigns against malaria in Mexico. To assess chronic occupational exposure, we studied a group of workers dedicated to spraying houses to control malaria vectors in the state of Veracruz. Exposure was directly estimated for a subgroup of 40 workers by measuring DDT metabolites in adipose tissue samples and indirectly estimated for 331 workers by using a questionnaire to determine their occupational history. Participants ranged in age from 20 to 70 years, and 80% of the workers had been employed in the sanitation campaign for at least 20 years. The mean concentrations of extractable lipids found in adipose tissue samples were as follows: total DDT, 104.48 micrograms/g; p,p'-DDE, 60.98 micrograms/g; p,p'-DDT, 31.0 micrograms/g; o,p'-DDT, 2.10 micrograms/g; and p,p'-DDD, 0.95 microgram/g. The DDT metabolite p,p'-DDE was selected as the indicator of chronic exposure. An index of chronic occupational exposure was constructed according to worker position and based on the historical duration and intensity of DDT application. A linear model including this index, the use of protective gear, and recent weight loss explained 55% of the variation of p,p'-DDE concentrations in adipose tissue. By this model, the predicted values of p,p'-DDE concentration in adipose tissue for the 331 workers are between 9.56 micrograms/g and 298.4 micrograms/g of fat, with a geometric mean of 67.41 micrograms/g. These high levels of DDT in adipose tissue call for exposure prevention programs and the promotion of more secure application measures and hygiene. We also discuss the use of indirect measures of DDT exposure in epidemiological studies of health effects.

Distribution and diffusivity of a hydrophobic probe molecule in the interior of a membrane: theory and simulation

We propose a simple model for the distribution of position and orientation and the diffusion of a hydrophobic probe molecule embedded in a membrane. The molecule experiences both a Maier-Saupe orienting potential as well as an enclosing potential of repulsion from the membrane walls. A statistical thermodynamics treatment of the model provides predictions of the location and orientation of the molecule within the membrane. In particular, we evaluate the order parameter of the molecule in terms of the model constants. The diffusivity of the probe is studied by Brownian dynamics simulation. For rotational diffusion, we check an available analytical approximate treatment that allows for the prediction of the dynamics in terms of equilibrium quantities. We also pay attention to quantities related to the initial and mean reorientational rate of the probe. For translational diffusion, we use the simulation results to analyze some general aspects of lateral and transversal diffusion.

Interobserver agreement using computed radiography in the adult intensive care unit

RATIONALE AND OBJECTIVES

We determined whether computed radiographs in an adult intensive care unit produce greater agreement between readers in descriptions of radiologic findings and interval changes.

METHODS

Fifty-six conventional radiographs and 56 computed radiographs were obtained on 28 patients. Computed and conventional radiographs were imaged simultaneously in a single exposure with the use of a sandwich cassette. The two sets of films per patient were taken less than 1 week apart.

RESULTS

Four readers evaluated the chest films and judged interval changes with the use of standardized confidence scales. Overall exposure and film quality also were evaluated. Computed radiographs were rated better in overall quality. Tubes and lines were detected with comparable accuracy. Interobserver agreement in the evaluation of radiologic descriptors was generally greater with computed radiographs (intraclass correlation). No differences were noted in interobserver agreement in the judgment of interval changes.

CONCLUSIONS

The diagnostic usefulness of computed radiography is comparable to conventional films in the intensive care unit. The higher interobserver agreement rate for radiologic descriptors with computed radiography is an added advantage of the system.

CT of gastric masses: image patterns and a note on potential pitfalls

Computed tomography (CT) was performed in 9 consecutive cases of primary gastric neoplasm. Lesions were surgically or endoscopically proved; cross-sectional images are correlated to specific histopathology in each case. The CT images of leiomyoma and leiomyoblastoma are characterized as models of pure bulging intramural growth resulting in a lunate contrast distribution when imaged in the cross-sectional plane. In 5 cases of lymphoma, distortion of the contrast-filled hollow viscus is relatively consistent. Nodular growth is reflected on the CT image as a series of digitations encroaching on the opacified portion of the gastric lumen. Image pattern recognition, relative to histopathology, is of more than academic interest since endoscopy is frequently unreliable in cases of submucosal and exophytic pathology. Further, biopsy of such lesions is commonly nondiagnostic as a result of random choice of biopsy site or inadequate depth of tissue sample. Additionally, this report includes images of lesions that simulate the primary gastric pathology and may be a source of erroneous interpretation. These include: pseudocyst of the pancreas (2 cases) and enlargement of the left lobe of the liver with encroachment on the gastric lumen (1 case). Image specificity on CT examination is increasingly essential to diagnosis and surgical planning.

Computed tomography in ileofemoral venous thrombosis: extension to inferior vena cava defined with foot vein infusion

Two cases of ileofemoral venous thrombosis and occlusion are presented in which cephalad extension of venous thrombosis to the inferior vena cava (IVC) is demonstrated on computed tomography (CT). Proximal venous obstruction does not diminish the utility of foot vein infusion simultaneous with the CT study. Delineation of intraluminal thrombosis in the IVC is excellent with good definition of occluded and patent segments of the IVC.