Innate gut microbiota predisposes to high alcohol consumption.

Gut microbiota is known to be transferred from the mother to their offspring. This study determines whether the innate microbiota of rats selectively bred for generations as high alcohol drinkers play a role in their alcohol intake. Wistar-derived high-drinker UChB rats (intake 10-g ethanol/kg/day) administered nonabsorbable oral antibiotics before allowing access to alcohol, reducing their voluntary ethanol intake by 70%, an inhibition that remained after the antibiotic administration was discontinued. Oral administration of Lactobacillus rhamnosus Gorbach-Goldin (GG) induced the synthesis of FGF21, a vagal ß-Klotho receptor agonist, and partially re-invoked a mechanism that reduces alcohol intake. The vagus nerve constitutes the main axis transferring gut microbiota information to the brain ("microbiota-gut-brain" axis). Bilateral vagotomy inhibited rat alcohol intake by 75%. Neither antibiotic treatment nor vagotomy affected total fluid intake. A microbiota-mediated marked inflammatory environment was observed in the gut of ethanol-naïve high-drinker rats, as gene expression of proinflammatory cytokines (TNF-α; IL-6; IL-1ß) was significantly reduced by nonabsorbable antibiotic administration. Gut cytokines are known to activate the vagus nerve, while vagal activation induces pro-rewarding effects in nucleus accumbens. Both alcoholics and alcohol-preferring rats share a marked preference for sweet tastes-likely an evolutionary trait to seek sweet fermented fruits. Saccharin intake by UChB rats was inhibited by 75%-85% by vagotomy or oral antibiotic administration, despite saccharin-induced polydipsia. Overall, data indicate that the mechanisms that normally curtail heavy drinking are inhibited in alcohol-preferring animals and inform a gut microbiota origin. Whether it applies to other mammals and humans merits further investigation.

A dual treatment blocks alcohol binge-drinking relapse: Microbiota as a new player.

RATIONALE: Gut microbiota communicates information to the brain. Some animals are born with a gut microbiota that predisposes to high alcohol consumption, and transplantation of fecal material from alcoholics to mice increases animal preference for ethanol. Alcohol-use-disorders are chronic conditions where relapse is the hallmark. A predictive animal model of relapse is the "alcohol deprivation effect" where ethanol re-access is allowed following chronic alcohol intake and a long alcohol deprivation. The present study evaluates the effect of gut microbiota modification on relapse, as an adjunct to N-acetylcysteine + Acetylsalicylic acid administration, which inhibits the alcohol-induced hyper-glutamatergic condition. METHODS: Rats bred as heavy alcohol consumers (UChB) were allowed ethanol intake for one month, were deprived of alcohol for two-weeks and subsequently offered re-access to ethanol. Prior to ethanol re-access animals received orally either (i) vehicle-control, (ii) Lactobacillus-rhamnosus-GG after antibiotic treatment (LGG); (iii) N-acetylcysteine+Acetylsalicylic acid (NAC/ASA) or (iv) both treatments: LGG+ (NAC/ASA). RESULTS: Marked binge drinking (1.75 g ethanol/kg in 60 min) and blood alcohol levels exceeding 80 mg/dl were observed in the control group upon ethanol-re-access. Lactobacillus-GG or (NAC+ASA) treatments inhibited alcohol intake by 66-80%. The combination of both treatments virtually suppressed (inhibition of 90%) the re-access binge-like drinking, showing additive effects. Treatment with NAC+ASA increased the levels of glutamate transporters xCT and GLT-1 in nucleus accumbens, while Lactobacillus-GG administration increased those of the dopamine transporter (DAT). CONCLUSIONS: The administration of a well-accepted probiotic may be of value as an adjunct in the treatment of alcohol-use-disorders.

First wave of SARS-CoV-2 in Santiago Chile: Seroprevalence, asymptomatic infection and infection fatality rate.

BACKGROUND: The first wave of SARS-CoV-2 infection in Chile occurred during the cold season reaching a peak by the end of June 2020, with 80 % of the cases concentrated in its capital, Santiago. The main objective of this study was to estimate the attack rate during this first wave of SARS-CoV-2 in a large, densely populated city with more than seven million inhabitants. Since the number of confirmed cases provides biased information due to individuals' potential self-selection, mostly related to asymptomatic patients and testing access, we measured antibodies against SARS-CoV-2 to assess infection prevalence during the first wave in the city, as well as estimate asymptomatic cases, and infection fatality ratio. To our knowledge this is one of the few population-based cross-sectional serosurvey during the first wave in a highly affected emerging country. The challenges of pandemic response in urban settings in a capital city like Santiago, with heterogeneous subpopulations and high mobility through public transportation, highlight the necessity of more accurate information regarding the first waves of new emerging diseases. METHODS: From April 24 to June 21, 2020, 1326 individuals were sampled from a long-standing panel of household representatives of Santiago. Immunochromatographic assays were used to detect IgM and IgG antibody isotypes. RESULTS: Seroprevalence reached 6.79 % (95 %CI 5.58 %-8.26 %) in the first 107 days of the pandemic, without significant differences among sex and age groups; this figure indicates an attack rate 2.8 times higher than the one calculated with registered cases. It also changes the fatality rate estimates, from a 2.33 % case fatality rate reported by MOH to an estimated crude 1.00 % (CI95 % 0.97-1.03) infection fatality rate (adjusted for test performance 1.66 % [CI95 % 1.61-1.71]). Most seropositive were symptomatic (81,1 %). CONCLUSIONS: Despite the high number of cases registered, mortality rates, and the stress produced over the health system, the vast majority of the people remained susceptible to potential new epidemic waves. We contribute to the understanding of the initial spread of emerging epidemic threats. Consequently, our results provide better information to design early strategies that counterattack new health challenges in urban contexts.

Imported scrub typhus: first case in South America and review of the literature.

BACKGROUND: Scrub typhus is a neglected vector-borne zoonosis causing life-threatening illnesses, endemic in the Asian-Pacific region and, as recently discovered, in southern Chile. Scrub typhus is rarely reported in travelers, most probably due to the lack of clinical experience and diagnostic tests in non-endemic countries. We report the first case of imported scrub typhus in South America. CASE PRESENTATION: A 62-year-old tourist from South Korea presented severely ill with fever, rash, and eschar in Santiago, Chile. Laboratory exams showed thrombocytopenia and elevated inflammation parameters, hepatic enzymes, and LDH. With the clinical suspicion of scrub typhus, empirical treatment with doxycycline was initiated and the patient recovered rapidly and without complications. The diagnosis was confirmed by IgM serology and by real-time PCR, which demonstrated infection with Orientia tsutsugamushi (Kawasaki clade). CONCLUSIONS: Only due to the emerging clinical experience with endemic South American scrub typhus and the recent implementation of appropriate diagnostic techniques in Chile, were we able to firstly identify and adequately manage a severe case of imported scrub typhus in South America. Physicians attending febrile travelers need to be aware of this rickettsiosis, since it requires prompt treatment with doxycycline to avoid complications.

Respuesta inmunitaria al SARS-CoV-2 y factores asociados previo a la vacunación, en personal de salud de atención primaria en una comuna de Santiago, Chile / Immune response to SARS-CoV-2 in Primary Health Care personnel from a commune of Santiago, Chile

INTRODUCCIÓN: La pandemia de COVID-19 surgida en China a fines de 2019, se extendió rápidamente por el mundo, con casi 600 millones de casos y 6,3 millones de fallecidos en la actualidad. Los más afectados fueron los trabajadores de la salud con al menos tres veces más riesgo que la comunidad general de contraer la enfermedad. La mayoría de los estudios sobre seroprevalencia en trabajadores de la salud, se enfocan en establecimientos de atención hospitalaria y no se ha indagado con igual intensidad sobre lo que ocurre en la Atención Primaria de Salud (APS). OBJETIVOS: Determinar prevalencia de SARS-CoV-2 mediante anticuerpos IgG en personal de atención primaria de comuna de La Pintana y explorar sus características clínicas y factores de riesgo, previo a la vacunación en Chile. METODOLOGÍA: Diseño transversal realizado en noviembre 2020. Se recogieron datos sociodemográficos y clínicos mediante entrevista cara a cara, previa firma de consentimiento. Se determinó IgG específica mediante ELISA que utiliza proteína N y S. Las diferencias entre sujetos positivos y negativos se estudiaron mediante análisis bivariado y para asociaciones encontradas, se desarrollaron modelos multivariados controlando potenciales variables de confusión. El estudio contó con la aprobación del Comité Ético Científico de la Universidad del Desarrollo. RESULTADOS: Participaron 463 funcionarios (51,4%) encontrando prevalencia de 21,8%. Los factores de riesgo fueron edad menor, ser médico y haber sido contacto estrecho de un caso. El 22% fue asintomático. Entre quienes presentan anosmia o ageusia, la probabilidad de IgG+ fue superior a 70%. Los títulos de anticuerpos aumentan significativamente con la gravedad. CONCLUSIONES: La prevalencia en personal de atención primaria encontrada es concordante con la evidencia previa en trabajadores de salud. La menor edad y la profesión de médico se asocian a un mayor riesgo de enfermar.

BACKGROUND: The COVID-19 pandemic that emerged in Wuhan, China at the end of 2019, spread rapidly around the world with almost 600 million cases and 6.3 million deaths today. The most affected were health workers with at least three times the risk of contracting the disease than the general community. Most studies on seroprevalence in health workers focus on hospital care establishments and what happens in Primary Health Care (PHC) has not been investigated with the same intensity. AIM: To determine the prevalence of SARS-CoV-2 using IgG antibodies in primary health care personnel in La Pintana commune, risk factors and clinical characteristics, prior to vaccination in Chile. METHODS: A cross-sectional design carried out in November 2020. Sociodemographic and clinical data were collected through face-to-face interviews, after providing informed consent. Specific IgG was determined by ELISA using N and S proteins. The differences between positive and negative subjects were studied using bivariate analysis and multivariate models, controlling for potential confounding variables. The study was approved by the Universidad del Desarrollo Scientific Ethics Committee. RESULTS: 463 employees (51.4%) participated, finding a prevalence of 21.8%. The risk factors found were younger age, being a physician and having been in close contact with a case. 22% were asymptomatic. Among those with anosmia/ageusia, the probability of IgG+ was greater than 70%. Antibody titers increase with severity. CONCLUSIONS: Prevalence found in primary health care personnel is consistent with previous evidence. Younger age and medical profession are associated with a higher risk of illness.

Pandemic influenza A (H1N1) 2009 with neurological manifestations, a case series.

OBJECTIVES: Describe a series of atypical presentations of pandemic influenza A (H1N1) 2009. METHODS: Description of case series using hospital records. RESULTS: Six patients aged 1 to 65 years with confirmed pandemic influenza A (H1N1) 2009 infection presented with neurological complications within 2 to 5 days after the first signs of influenza-like illness. All six were admitted with seizures or altered mental status. No abnormalities were found in brain scans or cerebral spinal fluid studies of any of the six. All were discharged without sequelae within days of admission. CONCLUSIONS: This is only the second report of pandemic influenza presenting with neurological manifestations. Clinicians caring for patients when pandemic influenza is prevalent in their communities should maintain a high level of awareness of the potential atypical presentations with which this disease can appear.

[Community acquired infections with methicillin resistant strains of Staphylococcus aureus: report of five cases]. / Staphylococcus aureus comunitario resistente a cloxacilina: Comunicación de los primeros cinco casos descritos en Chile.

Community acquired infections with methicillin resistant strains of Staphylococcus aureus (MRSA) infections have a more aggressive clinical course and involve mostly skin and lungs. These infections appear as outbreaks among prisoners, sportsmen, men having sex with men and military personnel. The higher aggressiveness of these strains is due to the production of several toxins, mainly Panton- Valentine leukocidine. The detection of the gene that codes for this toxin is a distinctive feature of these strains. We report five patients with community acquired MRSA infections. The clinical presentation was a skin infection in all. One patient had a pleuropneumonia in addition. Apart for resistance to beta-lactam antimicrobials, the strains were resistant to erythromycin and ciprofloxacin. Patients were treated with vancomycin, clotrimoxazole or intravenous clindamycin with a good evolution. An epidemiological surveillance for community acquired MRSA strain infections should be started and measures to adequately treat infected patients and avoid dissemination should be implemented.

Cirugía pulmonar en tuberculosis / Surgery for pulmonary tuberculosis: Review of 33 operated patients

Background: Surgical treatment for pulmonary tuberculosis is mainly ¡imited to the management of sequelae such as bronchiectasis, hemoptysis and brochopleural fistulae. Aim: To review the data of patients who underwent surgical treatment for pulmonary tuberculosis. Material and methods: Retrospective review of 33 patients aged 18 to 73 years (24 males) who underwent lung resection surgery for the management of pulmonary tuberculosis. Follow-up data were obtained from outpatient visit records and registries of the national tuberculosis program. Results: The reasons to perform surgery were the following: fifteen for hemoptysis, nine for lung destruction and nine for an active and multiresistant disease. No patient died in the postoperative period. The morbidity observed included empyema (n =5), pneumothorax (n =2), bronchopleural fístula (n =2) and hemothorax (n =2). At six months offollow up, six of the nine patients with active tuberculosis had negative acid-fast bacilli on sputum smear. Two of these patients died, one due to respiratory failure and another by an unrelated cause. Both dead patients had negative acid-fast bacilli on sputum smear. Conclusions: Surgery in pulmonary tuberculosis has a high rate of complications butmay be usefulin selected patients.

Staphylococcus aureus comunitario resistente a cloxacilina: comunicación de los primeros cinco casos descritos en Chile / Community acquired infections with methicillin resistant strains of Staphylococcus aureus: report of five cases

Community acquired infections with methicillin resistant strains of Staphylococcus aureus (MRSA) infections have a more aggresive clinical course and involve mostly skin and lungs. These infections appear as outbreaks among prisoners, sportsmen, men having sex with men and military personnel. The higher aggressiveness of these strains is due to the production of several toxins, mainly Panton- Valentine leukocidine. The detection of the gene that codes for this toxin is a distinctive feature of these strains. We report five patients with community acquired MRSA infections. The clinical presentation was a skin infection in all. One patient had a pleuropneumonia in addition. Apart for resistance to beta-lactam antimicrobials, the strains were resistant to erythromycin and ciprofloxacin. Patients were treated with vancomycin, clotrimoxazole or intravenous clindamycin with a good evolution. An epidemiológical surveillance for community acquired MRSA strain infections should be started and measures to adequately treat infected patients and avoid dissemination should be implemented.