ASEI es una revista científica de Fundación Huésped y la SADI que publica artículos sobre infectología, con foco en sida.
Fundación Huesped - Sociedad Argentina de Infectología
Recommendation for vaccination against respiratory syncytial virus (RSV) in adults
Respiratory syncytial virus (RSV) is a predominantly seasonal pathogen with an increasing incidence in Argentina (1). It is most prevalent among children under 2 years of age and older adults, particularly those with risk factors (cardiovascular diseases, chronic respiratory diseases, diabetes, immunocompromised individuals). Since there is no effective treatment for its management, disease prevention is of particular importance. Numerous studies have demonstrated that RSV vaccination in adults reduces the risk of illness, complications, and hospitalization in the most vulnerable populations (2, 3). Several countries have incorporated RSV immunization for adults into their respective immunization schedules in recent years. Although two vaccines are approved in our country, they have not yet been incorporated into the National Immunization Schedule. The Argentine Society of Infectious Diseases, through its Vaccine Commission, has issued this document, which provides valuable guidance for considering adult vaccination against this pathogen.
Copyright (c) 2026 Gabriela Vidal, Hebe Vázquez , Pablo Bonvehí, Francisco Nacinovich, Miriam Rozenek, Daniel Stecher https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Jaime passed away suddenly on May 19th. A large number of associations, scientific societies, biochemistry colleges, and universities bid him farewell with affection and gratitude for his tireless work and camaraderie. I take this opportunity to sketch the profile of a passionate professional, committed to public health and to the training of generations of biochemists and physicians. On behalf of the Editorial Committee of the ASEI Journal and myself, we express our gratitude for his invaluable collaboration as a reviewer for the Journal over the past two decades.
Communications from the Editorial Committee
Copyright (c) 2026 María Belén Bouzas https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Hantavirus: Understanding the Reservoir to Prevent the Disease
When a case of hantavirus cardiopulmonary syndrome (HCPS) is diagnosed, the process that led to that infection began much earlier. Disease in humans represents the final link in a complex chain of interactions between the environment, the wildlife reservoir, the virus, and human activities. Understanding this chain is essential for anticipating risky situations and guiding prevention strategies.
Copyright (c) 2026 Luciana Piuda https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
The epidemics of infectious diseases observed during the modern era were explained —and accepted— by the so-called Miasma theory. This view held that patients were overwhelmed by foul-smelling vapors resulting from the decomposition of organic matter —malodorous liquids that mixed in the air with gases emanating from abandoned, putrefying corpses. This theory is believed to have been first proposed by Sydenham and Lancisi in the 17th century, in a social environment characterized by a complete lack of environmental, residential, occupational, and personal hygiene.
Copyright (c) 2026 Jorge Benetucci https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Andes hantavirus: how evolving knowledge is leading to a new approach to intervention measures
Andes virus (ANDV) is the hantavirus of greatest relevance in Argentina and Chile, not only because of its environmental transmission associated with exposure in wild settings contaminated by the excreta of infected rodents, but also because of its intrinsic person-to-person transmissibility, which poses a unique public health challenge. This feature determines a clinical and epidemiological approach that differs from that used for other hantaviruses, especially with regard to the isolation of suspected and confirmed cases, as well as contact tracing and follow-up. The historic 2018–2019 outbreak transformed intervention strategies through the implementation of Selective Respiratory Isolation (SRI) for close contacts. The aim of this review is to analyze the evolution of scientific evidence between 2020 and 2026 regarding the mechanisms of salivary and respiratory transmission, viral persistence during convalescence, environmental stability of the pathogen, and the impact of new epidemiological surveillance protocols in Argentina. In conclusion, current evidence indicates that risk mitigation requires moving beyond a reactive response and consolidating comprehensive preventive strategies based on the One Health approach.
Copyright (c) 2026 Teresa Strella https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Carbapenem-resistant Acinetobacter baumannii infections: description of a cohort of hospitalized elderly patients
Carbapenem-resistant Acinetobacter baumannii (ABA-RCB) infections represent a critical global threat due to their limited therapeutic options. This observational, analytical and retrospective study (2021-2024) evaluated the clinical, epidemiological profile and outcome of 57 patients with confirmed ABA-RCB infection in a second level hospital in Rosario, Argentina. The mean age was 76.2 years (54% women). The main risk factors identified were previous use of antimicrobials (72%) and recent surgeries (47%). The most prevalent infections were pneumonia (54.39%) and those associated with prosthetic material (19.28%). Targeted treatment was predominantly performed as monotherapy (96.49%), using colistin in 79% of cases. A statistically significant association was recorded between antimicrobial treatment and worsening renal function (p=0.001). 75.44% of patients required care in the intensive care unit and overall mortality reached 61.40%. No statistically significant relationship was found between mortality and comorbidities, the infectious focus or the treatment regimen used. In conclusion, ABA-RCB infections in this population of older adults presented extremely high morbidity and mortality. Current clinical management is severely limited by the lack of access to new state-of-the-art antimicrobials, forcing the use of colistin monotherapies that carry high nephrotoxicity. These results underscore the urgent need for novel targeted therapies and optimization of early clinical suspicion.
Acinetobacter Baumannii. Antimicrobial resistance. Older adult
Copyright (c) 2026 Dra. Micaela Sandoval Guggia, Dra. Paloma Gonzalez, Dr. Juan Ignacio Rodriguez Lia, Dra. Micaela Montaldi, Dr. Andres Taborro, Dra. Daniela Gill https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Isolation of Delftia acidovorans in Respiratory Samples: Highlighting the Importance of Critical Interpretation and Quality Control in Clinical Microbiology
Delftia acidovorans is an environmental non-fermenting Gram-negative bacillus rarely associated with human infection. Its isolation from clinical specimens may generate diagnostic and therapeutic challenges. We report two hospitalized patients from a tertiary-care hospital in Neuquén Province, Argentina, in whom D. acidovorans was isolated from respiratory samples within a short period. Due to local laboratory limitations, isolates were referred for identification by MALDI-TOF mass spectrometry. Repeated recovery of this uncommon organism, together with poor clinicomicrobiological correlation, prompted an epidemiological investigation because of suspected pseudo-outbreak. An active search for contamination sources related to specimen collection and processing was performed. D. acidovorans was subsequently isolated from the N-acetylcysteine solution used as a mucolytic agent in the microbiology laboratory, confirming contamination during sample processing. This report underscores the importance of critical interpretation of microbiological findings, clinicomicrobiological correlation, and multidisciplinary collaboration to identify pseudo-outbreaks and prevent unnecessary antimicrobial treatment.
Delftia acidovorans; pseudo-outbreak; laboratory contamination; respiratory specimens; clinical microbiology.
Copyright (c) 2026 Lucia Ubertone, Walter Araya, Joaquín Manríquez, Macarena Delpupo, Paula De Benedetti, Karina Simonte https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
C5 complement inhibitors: mechanisms of action, indications, risk of infections, and prevention strategies
<pre id="tw-target-text" class="tw-data-text tw-text-large tw-ta" dir="ltr" style="text-align: left;" tabindex="-1" role="text" data-placeholder="Traducción" data-ved="2ahUKEwisgYyO69eUAxXajpUCHc6LLyUQ3ewLegQIDRAU" aria-label="Texto traducido: The C5 complement inhibitors eculizumab and ravulizumab are two monoclonal antibodies used to treat myasthenia gravis (MG), neuromyelitis optica spectrum disorder (NMOSD), atypical hemolytic uremic syndrome (aHUS), thrombotic microangiopathy (TMA), and paroxysmal nocturnal hemoglobinuria (PNH). These monoclonal antibodies target specific parts of the immune system and are therefore called targeted therapies. Their function is to block the C5 portion of complement, preventing its cleavage into C5a and C5b. The C5a portion has an inflammatory and prothrombotic effect; the C5b portion forms the terminal membrane attack complex (C5b-C9) (1, 2). In this way, inflammation that causes damage to the optic nerve, spinal cord and brainstem in NMOSD is stopped, destruction of the postsynaptic membrane is prevented in patients with MG, and hemolysis in PNH and thrombotic microangiopathy in HUS are controlled.">The C5 complement inhibitors eculizumab and ravulizumab are two monoclonal antibodies used to treat myasthenia gravis (MG), neuromyelitis optica spectrum disorder (NMOSD), atypical hemolytic uremic syndrome (aHUS), thrombotic microangiopathy (TMA), and paroxysmal nocturnal hemoglobinuria (PNH). These monoclonal antibodies target specific parts of the immune system and are therefore called targeted therapies. Their function is to block the C5 portion of complement, preventing its cleavage into C5a and C5b. The C5a portion has an inflammatory and prothrombotic effect; the C5b portion forms the terminal membrane attack complex (C5b-C9) (1, 2). In this way, inflammation that causes damage to the optic nerve, spinal cord and brainstem in NMOSD is stopped, destruction of the postsynaptic membrane is prevented in patients with MG, and hemolysis in PNH and thrombotic microangiopathy in HUS are controlled.
Comisión de Infecciones en el Paciente Inmunocomprometido
Copyright (c) 2026 Comisión de Infecciones en el Paciente Inmunocomprometido https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
The editorial team of Revista ASEI would like to express its sincere gratitude to the 51 reviewers who dedicated their time and expertise to the journal's meticulous editorial process over the past twelve months. During this period, 34 submissions were received and evaluated, of which 20 were accepted and published, 2 were rejected, and 12 were still under review at the end of 2025. Of the 20 published submissions, 7 were original articles, 4 were brief communications, 8 were case reports, and 1 was a review article. In addition, 6 editorials and 3 supplements were published.
Copyright (c) 2026 Comité Editorial https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Syphilis in Argentina: beyond the numbers
In recent years, syphilis has experienced a steady increase in Argentina, becoming one of the main challenges in the field of sexually transmitted infections (STIs). This upward trend, observed since the middle of the last decade, is reflected in the increase in notification rates, particularly among adolescents and young adults. According to data from Bulletin No. 42 on the Response to HIV and STIs in Argentina (1), the syphilis rate rose from 56.1 cases per 100,000 inhabitants in 2019 to 93 per 100,000 in 2024. The trend continued in 2025, with 46,613 confirmed cases, 71 % more than the median for the period 2020-2024 (2). It should be noted that the actual magnitude of the problem could be greater if underreporting of cases is taken into account. This scenario poses a specific health challenge. However, it is not enough to understand the phenomenon solely from the figures. Epidemiological data describe the magnitude of the problem, but do not fully explain its determinants. There is a less visible side to the STI epidemic, linked to biomedical, social, and cultural transformations that have changed sexual behaviors and perceptions of risk.
Copyright (c) 2026 Luciana Spadaccini https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
The flu, ever the same and ever different, has once again shown us new paths
The influenza virus is a significant cause of morbidity and mortality worldwide. In addition to its well-known respiratory impact, multiple studies have shown that it can act as a trigger for major clinical events (AMI, stroke, diabetic decompensation, among others), which are equally preventable or mitigable by the available vaccine (1, 2). The emergence of a new variant (subclade) of the influenza A (H3N2) virus raised concerns among the medical community and the general population and prompted the publication of several documents by various scientific societies with the aim of providing clear information and practical tools, as well as including vaccination recommendations and specific considerations for both those who had not been vaccinated during the 2025 season and those who had received their vaccines in a timely manner (3). This editorial aims to contribute some reflections to the debate based on this scenario, improve understanding of the disease, learn about its global impact, and facilitate control strategies.
Copyright (c) 2026 Francisco Nacinovich, Pablo Bonvehí https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Vertical transmission of Dengue: Report of a neonatal case in a high complexity center in Guayaquil, Ecuador.
Vertical transmission of neonatal dengue presents a diagnostic challenge in hyperendemic areas such as Guayaquil. We report the case of a female neonate, the daughter of a pregnant woman who died from severe peripartum dengue. The patient was admitted with severe perinatal asphyxia, renal injury, and myocardial damage. On the fifth day, she developed fever and a rash, and the diagnosis was confirmed by a positive NS1 antigen test. During the critical phase, she developed hemoconcentration, thrombocytopenia, and pulmonary edema due to capillary leak. Grade 2 intraventricular hemorrhage was also documented. Dynamic fluid management allowed for stabilization without the need for blood products. The patient was discharged in stable condition after 14 days with multidisciplinary follow-up. Publicizing this case raises suspicion of dengue in an underreported age group; timely perinatal detection is crucial to prevent mortality associated with severe complications.
Copyright (c) 2026 Andrés González, Joyce Andrade, Mildred Zambrano, Juan Chang https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Disseminated Cryptococcosis with Duodenal and Lymph Node Involvement in an Patient with AIDS: An Unusual Case Report
Cryptococcosis is a prevalent opportunistic infection in patients with advanced immunosuppression, although its extrapulmonary non-meningeal forms remain infrequent and poorly characterized. We present the case of a patient with AIDS who developed disseminated cryptococcosis with pulmonary, meningeal, lymph node, and duodenal involvement, the latter two being exceptionally reported manifestations. The diagnosis was confirmed through microbiological, radiological, and histopathological studies, and treatment required an induction regimen with amphotericin B followed by consolidation and maintenance with fluconazole, in a regional context where flucytosine is not available. This case underscores the importance of recognizing atypical presentations, considering dissemination in patients with gastrointestinal symptoms or lymphadenopathy, and highlights the need to generate local evidence and specific guidelines for these uncommon forms.
Copyright (c) 2026 Dr. Gabriel M Vicente, Dra Sabrina Appeceix, Dra Yisela Cuellar, Dra Mayumi Itati, José Benso, Verónica Fernández https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Inter-society document updating on dengue vaccination in Argentina
Dengue fever has become a serious public health problem in Argentina, with a progressive geographic expansion and a sustained increase in the number of cases. During the 2023-2024 season, more than 580,000 cases and 419 deaths were recorded, underscoring the urgent need to implement preventive strategies that complement vector control. Vaccination with TAK-003 represents a fundamental advance in dengue prevention in Argentina within the framework of a comprehensive disease control strategy.
Copyright (c) 2025 Octavia Bertachini, Pablo Bonvehí, Florencia Cahn, María Marta Contrini, Silvia González Ayala, Susana Lloveras, Alfonso Rodríguez Morales, Hebe Vázquez https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Dengue in the second trimester of pregnancy: a case of deciduitis, sub-amniotic hemorrhage, and fetal death
Dengue virus infections during pregnancy are on the increase, in line with the rise in cases in general population of this arboviral disease, which has the highest global burden. The maternal-fetal implications that dengue causes during pregnancy show heterogeneous evidence, with studies primarily focused on the third trimester and peripartum period, and few assessing associated risk factors or leading to anatomo-pathological studies. We describe a case of a pregnant woman with risk factors who aquired the infection during the second trimester, resulting in a fatal outcome for the fetus, and in whom an anatomo-pathological study of the ovular remains revealed deciduitis and sub-amniotic hemorrhage.
dengue, pregnancy, fetal death, placenta, hemorrhage
Copyright (c) 2026 Florencia Troglio, Javier Mesa, Gisela Wöhning, Daniel Rivas, Agustina Lacaze https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
HIV-TB co-infection in Argentina: an unresolved public health issue
Tuberculosis (TB) and HIV co-infection represents one of the most complex challenges for public health in Latin America and the Caribbean, and Argentina is no exception. In a regional context where both epidemics have shown sustained growth since 2015, the interaction between TB and HIV continues to have a disproportionate impact, particularly on the most vulnerable populations.
Copyright (c) 2025 Omar Sued, Pablo Avedillo https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Antiretroviral treatment: what is coming
Most people living with HIV who can access and take oral anti-retroviral therapy (ART) can enjoy a normal life expectancy. However, stigma (daily reminder of status and fear of disclosure), forgetting and the inconvenience of daily pills remain barriers to successful ART for some people (1). There is significant interest in longer-acting treatment modalities and the first ever complete long-acting (2-monthly) intramuscular injectable regimen for people who are virally suppressed was licensed for use in 2021. It consists of a novel integrase strand transfer inhibitor (INSTI) called cabotegravir, and rilpivirine, a non-nucleoside reverse transcriptase inhibitor (NNRTI). People who take it prefer it to daily oral therapy with high rates of treatment satisfaction and the discontinuation rates are low. The efficacy has been shown to be similar to that of daily oral ART in both clinical trials and clinical practice. However, the genetic barrier to resistance is lower and when virological failure occurs, single or dual class resistance is very common (2). Providing 2-monthly injections is labour-intensive for clinicians and uptake has not been as high as expected, mainly because it is not presented as an option universally. Data of off-license use in people who are not-virally suppressed are limited.
Copyright (c) 2025 Chloe Orkin https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Beyond cardiopulmonary syndrome: Hantavirus-associated parainfectious encephalitis
Hantavirus is a viral zoonosis transmitted primarily by rodents and classically associated with cardiopulmonary syndrome. Parainfectious neurological manifestations are rare and poorly documented in the literature. We present the case of a previously healthy 34-year-old man who developed hantavirus-associated parainfectious encephalitis as a complication of hantavirus infection. With intensive support, hemodialysis, and plasmapheresis, the patient achieved a favorable outcome. This case represents an important epidemiological and clinical contribution, highlighting the need to consider neurological manifestations in patients with hantavirus infection.
Hantavirus, Encephalitis, Zoonoses, Plasmapheresis
Copyright (c) 2025 Maria Alejandrina Guerrera, Micaela Nomdedeu, María José Teruggi, Juan Ignacio Irigoitia, Anabella Erviti, Guillermo Bertoni, Ailén Fernández, Nadia Baldoni, Florencia Otermin, Juan Manuel Poggio https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Atypical mycobacterial infections of skin and soft tissue
Introduction: Nontuberculous mycobacteria (NTM) are environmental pathogens of increasing importance, responsible for skin and soft tissue infections (STIs), frequently associated with aesthetic or surgical procedures. Objectives: To describe the epidemiology, clinical characteristics, causative agents, diagnostic correlation and evolution of patients with STIs due to NTM in a High Complexity center. Materials and methods: A descriptive, observational, and retrospective study was conducted between January 2015 and December 2023, including adults with positive cultures for NTM in skin or soft tissue samples. Clinical, microbiological, and evolutionary data were collected through review of medical records. Results: Seventeen patients were identified (mean age 46 years, range 23–79; 65% female); three were immunocompromised (17.6%). The predominant clinical presentation was abscesses or nodules. Seven patients (41%) had a history of previous cosmetic procedures. The most frequently isolated species was M. abscessus (41%). The mean time to diagnosis was 40 days by culture and 5 days by PCR, the latter allowing for early initiation of treatment. Histological examination showed chronic inflammation in 10 patients, with granulomas in 4. Eight patients achieved complete resolution, two experienced relapses, and one died. Discussion: NTM infections are an emerging cause of skin and soft tissue infections, linked to the increase in cosmetic procedures. The implementation of molecular techniques allows for rapid diagnosis and timely treatment.
Nontuberculous mycobacteria, skin and soft tissue infections, aesthetic procedures.
Copyright (c) 2026 Jessica del Valle Molina, Corina Nemirovsky, Marisa del Lujan Sanchez, Laura Barcan, Luz Guadalupe Ibañez https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Neurological Disorders Associated with Human Parvovirus B19v Infection in Immunocompetent Children
Human parvovirus B19v infection is associated with a wide range of clinical manifestations, including exanthem, arthralgia, fetal hydrops, aplastic crisis, and chronic anemia. Neurological complications are uncommon, with reported cases—mostly in children—describing encephalitis, meningitis, meningoencephalitis, encephalopathy, seizures, microcephaly, hydrocephalus, and cerebellar damage. Neuroimaging and electroencephalographic findings have been variable; while some patients recovered without sequelae, others had fatal outcomes (12%). We report two cases of immunocompetent children presenting with neurological manifestations associated with B19V infection, with no similar cases previously documented in our country. The current literature is limited and heterogeneous, and the true incidence of these presentations remains unclear. These findings underscore the need for further research into the neuropathogenic role of B19V and support its consideration in the differential diagnosis of acute neurological syndromes in pediatric patients.
Human parvovirus B19, neurological disorders, pediatric infection, inmunocompetent
Copyright (c) 2026 Alonso Alicia, Schuchinsky Alex, Figueredo Carlos, Batiuszko Alejandra, Espínola María, González Cecilia https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Update on hepatitis A vaccination in Argentina
This issue of ASEI presents an update on the topic prepared by the Vaccine Commission of the Argentine Society of Infectious Diseases (SADI). This update constitutes a fundamental tool for guiding clinical and public health decisions. The document reviews current indications, vaccination schedules, outbreak control strategies, and specificities in immunocompromised hosts. The Editorial Committee of the ASEI Journal encourages all healthcare teams to read, apply, and disseminate this document. Prevention, ultimately, remains the most effective tool for preserving the health of the population.
Copyright (c) 2025 Alejandra Gaiano, Andrea Mónaco, Martina De Prada, Mariana Golikow, Ana Ceballos, Gisela Calderón Arévalo, Gabriela Quintana , Silvia González Ayala https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Barriers in the HCV care cascade and medical knowledge in Argentina
Introduction: In Argentina, the prevalence of hepatitis C virus (HCV) infection is close to 0.5%. Only half of those affected are aware of their diagnosis, and less than 5% accessed treatment in 2020. Objective: To identify barriers in the care cascade and assess medical knowledge about HCV diagnosis and treatment. Methods: Anonymous survey distributed electronically between February and March 2025, targeting different physicians specialties. A total of 124 responses were analyzed using descriptive statistics. Results: Fifty-six percent of respondents were infectious disease specialists, 18% were clinicians, 11% were pediatricians, 8% were hepatologists, and 7% were general practitioners. Forty percent of respondents had more than 20 years of experience in the profession, and 27% had less than 10 years. Ninety percent were from Buenos Aires City and the province of Buenos Aires, and 70% worked in the public health system. The main setting was inpatient care 49 (46%) and outpatient care 43 (40%). The main barriers identified were diagnosis (53%), treatment (45%), and post-treatment follow-up (37%). Regarding diagnosis, 97% have serology and only 31% have serology, viral load, and genotype; with the possibility of referral in 100% of cases. Only 15% use reflex testing; the delay between diagnosis and treatment initiation was 2–6 months in 49% of cases. With respect to the treatment, less than half (36.2%) are aware of the treatments available in their workplace and their indications, and in 60% of cases, treatment is provided by hepatology and infectious disease specialists. Twenty-five percent do not feel qualified to prescribe treatment, and 30% are una}ware of direct-acting antiviral regimens. Conclusions: Currently, multiple barriers persist in the HCV care cascade in our country, and the situation is exacerbated by a lack of medical knowledge. There is an urgent need to move toward decentralization of diagnosis and treatment. Increasing the use of reflex testing, strengthening ongoing training for healthcare teams, and promoting intersectoral collaboration are essential to ensure sustained and equitable access to treatment.
Copyright (c) 2026 Dra. Gabriela Poblete, Marina Grand, Rufina Pérez, Liliana Calanni, Claudia Vujacich, Jorge Gentile, Emilia Cohen, Graciela Guaragna, Marcelo Gañete, Fabricio Morales, Yasmin El Kozah, Natalia Laufer https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Antibiotic therapy adequacy to PROA flowchart in community-acquired pneumonia in moderate care patients
Introduction: Antimicrobial Stewardship Programs (ASP) use evidence-based flowcharts to standardize infection management. Their implementation is rarely evaluated, limiting the validation of their impact. Objective: To evaluate the adequacy of antibiotic treatment according to the ASP flowchart in patients with community-acquired pneumonia (CAP) hospitalized in a moderate care unit at a tertiary care center. Methods: Observational, retrospective study (April-December 2024) was conducted on 50 immunocompetent patients ≥18 years of age with CAP hospitalized in a moderate care unit. Six adequacy indicators were analyzed (empirical selection, dosage, time to first dose < 4 hours, therapeutic adjustment, sequential therapy, and treatment duration), classified as optimal (>90%), intermediate (60-90%), or low (<60%). Results were expressed using descriptive statistics. Results: The mean age was 74.8 years, and 56% were male. Adequacy was low for four indicators: empirical selection (48%), therapeutic adjustment (23%), sequential therapy (55%), and treatment duration (16%). The time to first dose < 4 hours was appropriate at an intermediate level (66%). Correct dosage (96%) was the only indicator that reached an optimal level. Discussion: There are critical gaps in the antibiotic treatment adequacy in NAC associated with low adequacy of empirical antibiotic treatment and adjustment, delay and underuse of sequential therapy, and excessively prolonged treatments. Immediate interventions from the ASP Team are needed, focusing on training in empirical selection and therapeutic adjustment, mandatory reassessment protocols to counteract therapeutic inertia, support systems for sequential therapy and duration, and prospective audits with real-time feedback.
Copyright (c) 2025 Joaquín Ferreira Bacciarini, Angélica Benavente, Mariela Seguezza, Francisco Rodríguez De León, Paulina Brasó https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Infectious Endocarditis caused by Achromobacter xylosoxidans: Case report
Achromobacter xylosoxidans is a gram-negative, aerobic bacterium that causes invasive infections that are difficult to treat and have a high mortality rate. We present the case of a 75 years old man with a history of severe aortic stenosis admitted for acute pulmonary edema secondary to infective endocarditis, with positive blood and aortic valve cultures for said microorganism. Despite emergency clinical and surgical treatment, the patient died, highlighting the difficulty in managing endocarditis caused by rare microorganisms.
Achromobacter xylosoxidans, Infective Endocarditis, heart valves
Copyright (c) 2026 Lucia Guadalupe Guzmán, María Gabriela Peirotti, Evelyn Garro, Darío Conrado Quinodoz https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Pneumococcal vaccination: an ongoing challenge
Pneumonia and invasive pneumococcal disease are associated with high morbidity and mortality, underscoring the importance of vaccination as a preventive strategy. In Argentina, since 2017, a sequential vaccination schedule with the 13-valent pneumococcal conjugate vaccine (PCV13) and the 23-valent pneumococcal polysaccharide vaccine (PPSV23) has been recommended for adults aged 65 years and older, as well as for younger adults with comorbidities. The introduction of the 20-valent pneumococcal conjugate vaccine (PCV20) to replace the sequential scheme, has not only the purpose to simplify vaccination schedules but also improve adherence. The aim of this study was to describe the pneumococcal vaccination status among hospitalized adults in a Hospital in Buenos Aires, Argentina. An observational, descriptive, cross-sectional study was conducted among individuals aged 18 years and older with an indication for vaccination between November 2024 and February 2025. Patients were classified into three groups: complete vaccination (VC), incomplete vaccination (VI), and unvaccinated (NV). A total of 137 patients were analyzed; 56.9% were male, and the mean age was 74.3 years. Of them, 88.3% were older than 65 years; among younger patients, the predominant comorbidities were diabetes, smoking, HIV, and cancer. Overall, 46 patients (33.5%) had complete vaccination, 14 (10.2%) had an incomplete schedule, and 77 (56.2%) had not received any dose. None had received PCV20, as it was not available at our center during the study period. Our findings suggest that pneumococcal vaccination coverage remains suboptimal. It is essential to obtain data from local healthcare centers to develop targeted strategies to improve it.
Copyright (c) 2025 Marianela Paula López, Paula Castro, María Vanesa Durán https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Use of aminoglycosides in patients with intra-abdominal infections in a secondary acute care hospital
Aminoglycosides (AMG) are bactericidal, narrow-spectrum, and low-cost antibiotics, whose main limitation for clinical use is the risk of nephrotoxicity. The aim of this study was to characterize patients with intra-abdominal infections, describe the bacteriology and resistance profile, assess the frequency of acute kidney injury (AKI), and evaluate surgical outcomes. Materials and Methods: A prospective, observational study was conducted over one year, including hospitalized patients with intra-abdominal infections who received AMG therapy. AKI was defined as an increase in plasma creatinine of ≥0.3 mg/dL from baseline. Gentamicin serum levels and minimum inhibitory concentration (MIC) testing were performed. Results: A total of 126 patients were included, with a mean age of 51.6 years. The mean Karnofsky score was 89.8, and the mean Charlson comorbidity index was 1.8. The most frequent surgical diagnoses were appendicitis (38.9%), cholangitis (23%), and diverticulitis (13.5%). All patients received gentamicin, with a mean daily dose of 338.4 mg and a mean duration of 4.3 days. Escherichia coli was the most frequently isolated pathogen (68.8%), with 92.5% susceptibility to gentamicin. Clinical failure occurred in 15.1% of patients. AKI developed in 10.5% of cases, being mild in 91.7% and transient in 50%. Overall mortality was 3.2%. Patients who developed AKI were older and had higher Charlson and lower Karnofsky scores compared with controls (p<0.01). Conclusions: Aminoglycosides remain the antibiotic of choice in our setting, given their concordance with local antimicrobial susceptibility patterns. They showed a low rate of AKI and minimal therapeutic failure.
aminoglycosides, Gentamicin, Acute Kidney Injury, Anti-Bacterial Agents, Drug Resistance, Bacterial.
Copyright (c) 2026 Lucía Lamponi Tappatá, Diego Maurizi, Marisol Valle, Analía Álvarez, María Menichelli, Alex Schell, Matías Schulz, Marlene Bustelo, Naiara Paredes, Dina Pedersen, Celeste Martínez, Alejandra Oriani, Antonela Amusquibar, Pamela Dietrich, Mariano Echegorry, Alejandra Corso, Fernando Pasterán https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Giant exophytic mass as a rare presentation of Kaposi's sarcoma in a person living with HIV
Kaposi's sarcoma is the most common malignant tumor in people living with HIV. It typically affects the skin, mucous membranes, and lymph nodes, with the most frequent clinical presentation being erythematoviolaceous papules on the lower limbs, trunk, face, and oropharyngeal mucosa, with slow and centripetal dissemination. Visceral involvement may occur, with the gastrointestinal tract being the most frequent extracutaneous location. Evidence on atypical cutaneous presentations is limited in the literature. We present the case of a patient with a rare presentation of Kaposi's sarcoma, a giant exophytic mass resembling primary cutaneous lymphoma.
Copyright (c) 2026 Ana clara Irassar, Vanesa Dadon, Joaquín Cabral, Paola Staltari, Leandro Danze, Claudia G. Rodríguez, Ezequiel Córdova https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Lepromatous leprosy regarding a case diagnosed in Tierra del Fuego
Leprosy is a chronic, endemic and ubiquitous infectious disease. In 2000, the World Health Organization declared the elimination of leprosy as a global public health problem. Although the prevalence has decreased drastically since the introduction of multidrug therapy, there are still a considerable number of cases appearing in central African countries, India, China and Brazil (1, 2, 3). In Argentina, there are 400 cases per year under treatment, and a geographic focus on provinces in the northeast, northwest and center of the country, which concentrate approximately 70% of the cases (4, 5). The importance of reporting this case in Tierra del Fuego is due to the fact that it is not an endemic area of leprosy and since it is not a public health problem, it is difficult to diagnose because physicians do not suspect it as a possible differential diagnosis within dermatoses (1).
Leprosy, bacilloscopy multibacillary, Tierra del Fuego.
Copyright (c) 2025 Carla Cabrera, Mariela Toledo, Pablo Berenstein, Juan Manuel Márquez https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
We present the case of a 58-year-old male patient from Santiago del Estero, a rural worker, who consulted for an inflammatory tumor involving skin and deep tissues of the right foot, which has an estimated evolution of two years. Microbiological cultures showed dry and cerebriform colonies, which were identified as Streptomyces sp. by MALDI TOF mass spectrometry, BD Bruker ® and whole genome sequencing. The condition was diagnosed as actinomycetoma. Imaging studies showed bone involvement, so treatment with trimethoprim-sulfamethoxazole and minocycline was initiated. However, due to the development of pulmonary tuberculosis, treatment was adjusted to rifampin, ethambutol, pyrazinamide, isoniazid, and trimethoprim-sulfamethoxazole, with favorable clinical outcome.
Streptomyces sp, actinomycetoma, micetoma
Copyright (c) 2026 Cinthya Indira Vargas Coello, Carolina Ugarte, Yamila Vallejos, María Sol Haim, Tomás Poklépovich, Nadina Caraballo, Noelia Costanzo, Mariela Schijman, María Emilia Villani https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es
Detection of viral agents in cerebrospinal fluid in pediatrics: 7 years of experience
The diagnosis of viral meningoencephalitis and encephalitis is a frequent challenge in pediatrics and the establishment of viral etiology by polymerase chain reaction (PCR) is important because it allows guiding treatment and avoiding the unnecessary use of antibiotics. We designed a retrospective study with the aim of describing the frequency of distribution of viral agents detected in cerebrospinal fluid (CSF) of children with suspected meningoencephalitis/viral encephalitis, assessing the percentage of HSV1-2 detection in second lumbar puncture when the first result was negative and correlating with the cytophysicochemical study. CSF samples collected in the period April 2017 to February 2024 from 590 hospitalized patients were analyzed with mutiplex PCR Meningitis/Encephalitis Panel (FilmArray, Biofire Diagnostics) and commercial techniques for HSV1-2. At least one viral agent was detected in 17% of the samples, with the highest frequency of Enterovirus: 10.8%, Human Herpes-6: 3.9% and HSV1: 1.9%. Patients with detectable PCR presented meningoencephalitis: 53% and encephalitis 19%. In 22% of cases they were associated with other pathologies. All second samples (40/590) tested for HSV1-2 were negative. Cytophysicochemical tests showed no differences between cases of herpetic and non-herpetic encephalitis.
Viral meningoencephalitis, Herpetic encephalitis, Cerebrospinal fluid, Herpes simplex virus, Viral diagnosis.
Copyright (c) 2025 Maria Juliana Palau, Natalia Treviño, Maria Paula Eguiguren, Lucía Zaccarello, Sebastián Oderiz, Cecilia Vescina https://creativecommons.org/licenses/by-nc-sa/4.0/deed.es