Low-dose chest CT for preoperative screening for SARS-CoV-2 infection.

INTRODUCTION: This study aimed to evaluate the role of chest computed tomography (CT) in complementing reverse transcription polymerase chain reaction (RT-PCR) in asymptomatic candidates for elective surgery in the context of the COVID-19 pandemic. MATERIAL AND METHODS: We prospectively included 464 asymptomatic patients who underwent a triple screening workup for SARS-CoV-2 infection (health questionnaire, RT-PCR, and low-dose chest CT) during the 48 h prior to undergoing elective surgery. A positive RT-PCR and/or CT findings suggestive of COVID-19 (CO-RADS 4/5) were considered diagnostic criteria for SARS-CoV-2 infection. RESULTS: Most patients (64.7%) underwent otorhinolaryngology surgery. No patients had positive RT-PCR results or symptoms suggestive of SARS-CoV-2 in the health questionnaire. Only 22 (4.7%) had signs compatible with lung infection; in 20 of these, the CT findings were atypical or indeterminate for COVID-19 (CO-RADS 2/3) and in 2 they were compatible with COVID-19 pneumonia in resolution. In the immediate postoperative period, no cases of SARS-CoV-2 infection were confirmed. CONCLUSION: In our series of asymptomatic patients, low-dose CT did not add any value to the results of RT-PCR and a health questionnaire in preoperative screening for SARS-CoV-2.

[Low-dose chest CT for preoperative screening for SARS-CoV-2 infection]. / TC torácica de baja dosis de radiación como técnica de cribado preoperatorio de infección por SARS-CoV-2.

Introduction: This study aimed to evaluate the role of chest computed tomography (CT) in complementing reverse transcription polymerase chain reaction (RT-PCR) in asymptomatic candidates for elective surgery in the context of the COVID-19 pandemic. Material and methods: We prospectively included 464 asymptomatic patients who underwent a triple screening workup for SARS-CoV-2 infection (health questionnaire, RT-PCR, and low-dose chest CT) during the 48 hours prior to undergoing elective surgery. A positive RT-PCR and/or CT findings suggestive of COVID-19 (CO-RADS 4 / 5) were considered diagnostic criteria for SARS-CoV-2 infection. Results: Most patients (64.7%) underwent otorhinolaryngology surgery. No patients had positive RT-PCR results or symptoms suggestive of SARS-CoV-2 in the health questionnaire. Only 22 (4.7%) had signs compatible with lung infection; in 20 of these, the CT findings were atypical or indeterminate for COVID-19 (CO-RADS 2 / 3) and in 2 they were compatible with COVID-19 pneumonia in resolution. In the immediate postoperative period, no cases of SARS-CoV-2 infection were confirmed. Conclusion: In our series of asymptomatic patients, low-dose CT did not add any value to the results of RT-PCR and a health questionnaire in preoperative screening for SARS-CoV-2.

Carcinoma epidermoide de cuello uterino con extensión superficial a endometrio / Squamous cell carcinoma of the cervix with superficial extension to the endometrium

El cáncer de cuello uterino es la neoplasia más frecuente del tracto genital femenino, que en su forma avanzada puede invadir localmente a tejido paracervical, vagina, vejiga y recto. Se presenta un caso, muy poco frecuente, de carcinoma cervical con extensión endometrial como neoplasia in situ, en una paciente de 76 años y que se manifestó clínicamente como piometra.

Cervical cancer is the most common malignant tumor of the female genital tract, which in its advanced stage can invade locally paracervical tissue, vagina, bladder and rectum. A case extremely rarely is reported of cervical carcinoma with in situ carcinoma involving to endometrium in a patient of 76 years old and clinically manifested as pyometra.

[Mediastinal Castleman's disease: report of one case]. / Enfermedad de Castleman, un diagnóstico diferencial que no se debe olvidar en los tumores de mediastino: Caso clínico.

Castleman's disease is an uncommon lymphoproliferative disorder which can be unicentric or multicentric. Hialine vascular variant is the most common pathologic form, which is usually unicentric and presenting as mediastinal tumors. We report a 31-year-old female with a history of retrosternal pain. A chest CAT sean showed a tumor in the posterior mediastinum. The patient was operated and the tumor excised. The pathology report showed a Castleman's disease. No other tumors were found in the patient, who had a favorable evolution.

Enfermedad de Castleman, un diagnóstico diferencial que no se debe olvidar en los tumores de mediastino: Caso clínico / Mediastinal Castleman's disease: Report of one case

Castleman's disease is an uncommon lymphoproliferative disorder which can be unicentric or multicentric. Hialine vascular variant is the most common pathologic form, which is usually unicentric and presenting as mediastinal tumors. We report a 31-year-old female with a history of retrosternal pain. A chest CAT sean showed a tumor in the posterior mediastinum. The patient was operated and the tumor excised. The pathology report showed a Castleman's disease. No other tumors were found in the patient, who had a favorable evolution.

Fusión esplenogonadal: reporte de 1 caso / Splenogonadal fusion: report of one case

Se presenta el caso de un paciente operado por tumor testicular izquierdo, cuyo estudio anatomopatológico concluyó una fusión esplenogonadal. Se entrega información respecto a esta rara malformación y se mencionan herramientas diagnósticas que pueden ayudar al diagnóstico preoperatorio con la consiguiente reducción de la cirugía radical testicular.

Relaxation by calcium antagonists of potassium-contracted trachea from normal and sensitized guinea-pigs: influence of epithelium and the surface of drug entry.

A technique by which drug access was restricted to either the mucosal or the adventitial surface of tracheal rings, isolated from normal (unsensitized) or sensitized guinea-pigs, was used to study the role of the epithelium in the relaxation produced by calcium antagonists (verapamil, nifedipine, cinnarizine and flunarizine) of K(+)-induced contraction. In trachea from normal guinea-pigs, the relaxation to verapamil for unrestricted or mucosal drug entry was reduced in the absence of epithelium, whereas the relaxation produced by nifedipine, cinnarizine or flunarizine was unchanged. In sensitized trachea, the relaxation elicited by the calcium antagonists tested was similar in intact and epithelium-denuded tracheal rings irrespective of the surface of drug entry. These results confirm that the epithelium influences the relaxation to verapamil. This modulatory effect is absent in sensitized trachea and is not shared by other calcium antagonists.

Relationship between enterotoxigenic Escherichia coli and diarrhea among children in Buenos Aires.

The incidence of enterotoxigenic Escherichia coli (ETEC) has been studied in 85 children with acute diarrhea in patients in the Hospital de Niños Pedro de Elizalde, Buenos Aires, and in 38 healthy children. All of them were up to four years old and none had received antibiotic treatment within 7 days before sampling. ETEC was recovered in 9 out of 85 (10.6%) children with diarrhea. From these positive cases, 6 were associated with heat-stable (ST), 1 with heat-labile (LT) and 2 with both LT and ST enterotoxins. Only one case (2.6%) of LT-producing ETEC was detected in the control group. In 5 out of 9 ETEC diarrhea cases (55.5%) the isolated strains expressed human colonization factor antigens (CFA); four of them were CFA/I and one CFA/II. The characteristics of the CFA, biotype, serotype and antibiotic sensitivity pattern were studied in 23 E. coli isolates from 10 ETEC positive children. Of the 12 ST only strains, 5 (41.7%) expressed CFA/I and 2 (16.7%) CFA/II (CS2 + CS3). One out of 2 LT/ST strains expressed CFA/I. CFAs were not detected in the ETEC-LT nor in the toxin negative E. coli strains. From the ETEC isolated, 82.4% were resistant to 4 or more antibiotics, whereas only 50% of simultaneously isolated toxin-negative E. coli presented this sensitivity pattern. The different ETEC strains belonged to several different serotypes, some of them rarely observed in other countries. None of these serotypes correlated either with the toxin profile or with the sugar fermentation pattern.(ABSTRACT TRUNCATED AT 250 WORDS)

Epithelium modulates the reactivity of sensitized guinea-pig trachea: influence of the surface of drug entry.

A technique by which drug access was restricted to either the mucosal or the adventitial surface of tracheal rings isolated from sensitized guinea-pigs was applied to study the role of the epithelium in modulating responses to KCl, acetylcholine, histamine and antigen (bovine serum albumin, BSA). Epithelium removal did not alter the responsiveness or sensitivity of tracheal rings to KCl. In contrast, a leftward shift occurred for concentration-response curves to acetylcholine (concentration ratio (CR) = 4.1), histamine (CR = 2.9) and BSA (CR = 33.9) entering from the mucosal surface of de-epithelialized trachea. This shift was not associated with changes in the maximal effect of the spasmogens. Response to the adventitial entry of these spasmogens was not altered by epithelial stripping. These results confirm that the epithelium modulates tracheal responses to certain spasmogens including antigen challenge. This role was exclusively exerted for mucosal drug entry. The mechanism underlying this protective effect of epithelium remains to be determined.

Role of epithelium in agonist-induced contractile responses of guinea-pig trachealis: influence of the surface through which drug enters the tissue.

1. A method has been used in guinea-pig isolated tracheal rings to achieve selective drug entry from the adventitial or mucosal surface. A study has been made of the effects of epithelium removal on responses to spasmogens entering the tissue solely from the adventitial or the mucosal surface. 2. Cumulative concentration-response curves for KCl (1 to 100 mM), acetylcholine (0.1 microM to 10 mM) and histamine (1 microM to 1 mM) were constructed in intact and epithelium-denuded tracheal rings in circumstances where drug entry was unrestricted or restricted to the adventitial or mucosal surface. 3. Epithelium removal did not alter the responsiveness or sensitivity of tracheal rings to KCl either when drug entry was unrestricted or when drug entry was restricted to the adventitial or mucosal surface. 4. When acetylcholine entered from the mucosal or adventitial surfaces of intact tracheal rings its concentration-response curve was displaced to the right with respect to that obtained for unrestricted drug entry. A greater rightward shift was observed for mucosal drug entry than for adventitial drug entry. Epithelium removal potentiated acetylcholine entering from the mucosal surface to a greater extent (27.5 fold) than it potentiated acetylcholine entering from both surfaces (4 fold). Epithelium removal did not potentiate effects of acetylcholine entering from the adventitial surface alone. 5. In intact tracheal segments, concentration-response curves for histamine entering from the mucosal surface were displaced to the right compared with those for histamine entering in an unrestricted fashion or from the adventitial surface alone. This displacement was absent in epithelium-denuded preparations. Epithelium removal potentiated (2-3 fold) histamine entering from the mucosal surface or entering in an unrestricted way. It did not potentiate histamine entering from the adventitial surface alone. 6. Our findings suggest that the epithelium does not modulate tracheal responses to KC1. Its ability to modulate responses to acetylcholine and histamine is observed when these spasmogens enter the tissue from the mucosal surface but not when they enter from the adventitial surface. The mechanism by which epithelium removal preferentially potentiates acetylcholine and histamine entering from the mucosal rather than the adventitial surface remains to be determined.

Non-specific hyperreactivity to pharmacological stimuli in tracheal and lung parenchymal strips of actively sensitized guinea-pigs.

The responsiveness of tracheal and lung parenchymal strips isolated from actively sensitized guinea-pigs to CaCl2 (in K+-depolarized tissue), KCl, acetylcholine and histamine was compared with that of strips from unsensitized animals. The concentration-response curves to the mentioned agonists exhibited, in the sensitized group, a left upward displacement (greater maximal effect, lesser effective concentration 50% and a steeper slope) compared with those obtained in the unsensitized group. These results indicate the existence of a non-specific increase in responsiveness in the airway smooth muscle from sensitized animals.

Action of methylene blue and haemoglobin in rabbit aorta in relation to the surface of drug entry.

The effect of methylene blue and haemoglobin has been evaluated by using a procedure of restricting drug entry to one surface of rabbit aortic rings. In preparations precontracted with noradrenaline, methylene blue and haemoglobin produced, via the intima, an additional rapid and endothelium-dependent contraction. While haemoglobin was without effect via the adventitia, methylene blue produced a slow endothelium-independent contraction that was diminished but not abolished in reserpine-pretreated animals. This augmentation of the noradrenaline-induced contraction produced by methylene blue via the adventitia in reserpine-pretreated rabbits was observed also with phenylephrine but not with methoxamine. Methylene blue, when added to aortic rings incubated with 3H-(-)-noradrenaline, interfered with the neuronal uptake of this amine and enhanced the outflow of 3H. In conclusion, methylene blue and haemoglobin enhanced noradrenaline-induced contraction by an endothelium-dependent mechanism when applied via the intima. Haemoglobin is devoid of effects via the adventitia but methylene blue has indirect sympathomimetic effects. In experiments using intact rings with no restriction to drug entry it was found that the enhancement by haemoglobin of the tyramine-induced response was markedly less than that observed for noradrenaline for the same level of plateau contraction. This finding indicates that the endothelium-derived relaxing factor is more effective on smooth muscle cell layers in the vicinity of intima than on those close to adventitia.

Responses of rabbit aorta to tyramine in relation to the surface of drug entry.

The contraction elicited by submaximally effective concentrations of tyramine in the rabbit aortic strip occurs after a shorter latency and increases at a higher initial velocity to a greater steady-state level when drug entry is limited to the adventitial than when it is limited to the intimal surface. The reverse was true for noradrenaline. Both amines elicited equal maximum responses with independence of the surface of entry into the vascular wall. Differences between steady-state contractions disappear when the intramural disposition pathways of tyramine are blocked pharmacologically by a combination of pargyline and semicarbazide. Incubation with cocaine and pretreatment with reserpine resulted in a reversal of the surface of entry related differences between steady-state contractions to tyramine related to differences of the surface of entry. This reflected the unmasking of the direct component of the action of tyramine. Thus, the technique of limited drug entry into the vascular wall together with blockade of disposition pathways allows us to characterize the pre- and postsynaptic components of the action of tyramine.