Revista Do Instituto De Medicina Tropical De Sao Paulo最新文献

{"title":"Frequency of macrolide resistance-associated mutations in Mycoplasma genitalium: a multicenter molecular analysis based in Brazil.","authors":"Fernando Hartmann Barazzetti, Marcos André Schörner, Vilmar Benetti Filho, Henrique Borges da Silva Grisard, Julia Kinetz Wachter, Jéssica Motta Martins, Christinni Machado Venturi, Pâmela Cristina Gaspar, Angélica Espinosa Miranda, Dráurio Barreira, Glauber Wagner, Maria Luiza Bazzo","doi":"10.1590/S1678-9946202668070","DOIUrl":"https://doi.org/10.1590/S1678-9946202668070","url":null,"abstract":"<p><p>Mycoplasma genitalium is an emerging sexually transmitted pathogen with increasing antimicrobial resistance worldwide. In Brazil, molecular testing for M. genitalium and resistance-associated mutations is not routinely available, and national data remain scarce. We analyzed 118 M. genitalium-positive urethral and vaginal swab samples collected between 2018 and 2023 from sites across all five Brazilian geographic regions. PCR amplification and sequencing of 23S rRNA, parC, and gyrA identified macrolide and fluoroquinolone resistance-associated mutations. Among 79 samples successfully sequenced for 23S rRNA, 40.5% harbored macrolide resistance-associated mutations (A2058G, A2059G, or A2058T) detected in samples from all five regions at different frequencies. A total of 6.1% of sequenced samples presented parC mutations, including two with combined 23S rRNA and parC mutations. No resistance-associated mutations were detected in gyrA. While resistance-associated mutations occurred in both symptomatic men and pregnant women, these findings are not representative estimates for the Brazilian population since the study used convenience samples from two distinct surveillance populations. Nonetheless, they provide multicenter molecular data that may inform future surveillance, diagnostic strategies, antimicrobial stewardship, and resistance-guided management of M. genitalium in Brazil.</p>","PeriodicalId":54466,"journal":{"name":"Revista Do Instituto De Medicina Tropical De Sao Paulo","volume":"68 ","pages":"e70"},"PeriodicalIF":1.3,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13686527/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149247550","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"First clinical-epidemiological profile of zoonotic sporotrichosis in a state capital of Northeast Brazil: evidence of an emerging feline-driven urban epidemic.","authors":"Thiago Dutra Mendonça, Rayssa de Sousa Silva, Sirlei Garcia Marques, Gustavo Silva Santos de Sousa, Bianca de Fátima Assunção Sodré, Ayrton Rocha Lima, Guilherme Alencar de Medeiros, Daniel Wagner de Castro Lima Santos, Conceição de Maria Pedrozo E Silva de Azevedo","doi":"10.1590/S1678-9946202668069","DOIUrl":"https://doi.org/10.1590/S1678-9946202668069","url":null,"abstract":"<p><p>Zoonotic sporotrichosis has expanded in Brazil as an urban, cat-associated mycosis, but its human clinical-epidemiological profile remains poorly characterized in Maranhao State, Brazil. This study describes a hospital-based cohort from Greater Sao Luis and defines a regional profile not previously established in the state. We conducted an observational study combining retrospective and prospective data from 2022 to 2025 at a reference hospital for infectious diseases in Sao Luis municipality, Maranhao State, Brazil. Confirmed cases were defined by culture and/or compatible histopathological findings supported by clinical-epidemiological criteria. Demographic, exposure, clinical, laboratory, therapeutic, and outcome variables were analyzed using descriptive statistics and appropriate statistical tests. A total of 189 confirmed cases were analyzed. Cases increased sharply after 2022 and peaked in 2024, with 82 cases. Most patients lived in Sao Luis municipality (84.7%), were female (67.2%), and were aged 30-59 years (47.1%). Feline-associated exposure predominated: 70.9% reported having household cats and 81.5% reported scratches or contact with feline lesions or secretions. The lymphocutaneous form was the main presentation (61.9%), followed by fixed cutaneous disease (29.1%); upper limbs were the most frequently affected sites (73.0%). Culture was positive for Sporothrix spp. in 62.2% of tested samples, and suppurative granulomas were frequent findings on histopathological examination. Itraconazole was the first-line therapy in 92.0% of treated patients. Greater Sao Luis shows the profile of an emerging urban epidemic of zoonotic sporotrichosis of feline origin. These findings provide local evidence to guide surveillance, early diagnosis, integration between human and veterinary health services, and One Health-based control strategies in Maranhao State.</p>","PeriodicalId":54466,"journal":{"name":"Revista Do Instituto De Medicina Tropical De Sao Paulo","volume":"68 ","pages":"e69"},"PeriodicalIF":1.3,"publicationDate":"2026-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13686526/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149247540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clinical characteristics and exploratory outcome associations among patients hospitalized with acute febrile illness during a post-flood period: a multicenter cohort study from Vietnam.","authors":"Tuan Quoc Le, Thuy Ngoc Tran, Ngoc Quynh Bui, Hoang Thi Thuy Kieu, Thi Thao Ma, Hoang Duc Dong","doi":"10.1590/S1678-9946202668068","DOIUrl":"10.1590/S1678-9946202668068","url":null,"abstract":"<p><p>Flooding can disrupt sanitation, contaminate water sources, and alter patterns of infectious disease; however, causal attribution of an individual febrile illness episode to flood exposure is difficult in retrospective hospital-based data. This study described hospitalized patients with acute febrile illness during a post-flood period in northern Vietnam, exploring associations with adverse short-term outcomes. This multicenter retrospective observational cohort included 237 consecutive patients admitted in Thai Nguyen province from October to November 2025. Demographic, documented environmental, clinical, laboratory, etiologic, and treatment data were obtained from medical records. Severe disease occurred in 8.4% and treatment non-response in 6.8% of patients. At admission, mean high-sensitivity C-reactive protein (hs-CRP) was 103.3 ± 98.3 mg/L, procalcitonin (PCT) was 6.7 ± 11.6 ng/mL, AST was 55.6 ± 61.4 U/L, ALT was 42.5 ± 46.2 U/L, and GGT was 79.9 ± 70.7 U/L. Recorded etiologic diagnoses most commonly included Escherichia coli (33.3%), Vibrio cholerae (18.1%), influenza viruses (13.5%), Leptospira species (11.0%), and Streptococcus pneumoniae (11.0%). Ceftriaxone was administered to 61.5% of patients. Separate univariable exploratory analyses associated severe-flood residence, non-clean water use, chronic disease history, hs-CRP > 100 mg/L, PCT > 2 ng/mL, and fever duration ≥ 3 days with adverse outcomes. These findings represent within-cohort associations among patients from flood-affected communities and do not indicate that flooding caused the illness episodes or outcomes. Most patients exhibited favorable short-term outcomes.</p>","PeriodicalId":54466,"journal":{"name":"Revista Do Instituto De Medicina Tropical De Sao Paulo","volume":"68 ","pages":"e68"},"PeriodicalIF":1.3,"publicationDate":"2026-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13641769/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149139477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Regional distribution of serological evidence of vaccine-induced immunity to hepatitis B among cancer patients in a city in southeastern Brazil.","authors":"Victória Gonçalves de Paula, Marina Rossi de Camargo Pinto, Gustavo Manoel Ferreira, Débora Bignotto Rosane Battaglia, Rafael de Oliveira, Caroline Manchiero, Bianca Peixoto Dantas, Fátima Mitiko Tengan, Edson Abdala, Mariana Cavalheiro Magri","doi":"10.1590/S1678-9946202668066","DOIUrl":"10.1590/S1678-9946202668066","url":null,"abstract":"<p><p>Vaccination is the primary strategy for preventing hepatitis B virus (HBV) infection, but its frequency remains insufficiently characterized among cancer patients. This study evaluated the regional distribution of serological evidence compatible with vaccine-induced immunity to hepatitis B among cancer patients residing in Sao Paulo city, Brazil. We conducted a retrospective observational study of adult patients who underwent hepatitis B surface antibody (anti-HBs) serological testing at the Instituto do Cancer do Estado de Sao Paulo (ICESP) in 2023. Serological evidence compatible with vaccine-induced immunity was defined as reactive anti-HBs and non-reactive hepatitis B core antibody (anti-HBc). Univariable and multivariable Poisson regression analyses were performed to identify associated factors. Among 1,143 patients, the mean age was 57.4 ± 16.42 years, 61.9% were female, 60.6% self-identified White, and 76.8% had solid tumors. Overall, 26.2% of cancer patients had serological evidence compatible with vaccine-induced immunity to hepatitis B. Descriptively, the North Zone had a lower frequency than the South Zone (20.7% versus 28.9%), although regional differences were not statistically significant after multivariable adjustment. Female sex (adjusted prevalence ratio [aPR] = 1.67, 95% CI: 1.23-2.27, p = 0.001) and younger age (18-39 years versus ≥ 60 years: aPR = 6.89, 95% CI: 4.72-10.95, p < 0.001) were independently associated with serological evidence compatible with vaccine-induced immunity. These findings indicate a low frequency of serological evidence compatible with vaccine-induced immunity to hepatitis B among cancer patients across Sao Paulo, particularly among older adults and men.</p>","PeriodicalId":54466,"journal":{"name":"Revista Do Instituto De Medicina Tropical De Sao Paulo","volume":"68 ","pages":"e66"},"PeriodicalIF":1.3,"publicationDate":"2026-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13641768/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149139546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sentinel surveillance of acute febrile illness in a Brazilian Amazon region: laboratory findings and epidemiological implications.","authors":"Erick Matheus Garcia Barbosa, Antonio Charlys da Costa, Noely Evangelista Ferreira, Heuder Gustavo Oliveira Paião, Wilton Santos Freire, Anderson Vicente de Paula, Layla Honorato, Vanessa Dos Santos Morais, Márlisson Octávio da Silva Rego, Edcelha Soares D'Athaide Ribeiro, Diuliana Dos Santos Mendes, Júlia Pantoja Marques, Geovani de Oliveira Ribeiro, Steven Sol Witkin, Tania Regina Tozetto-Mendoza, Maria Cassia Mendes-Correa","doi":"10.1590/S1678-9946202668067","DOIUrl":"10.1590/S1678-9946202668067","url":null,"abstract":"<p><p>The Amapa State, Brazil, in the Amazon region and bordering French Guiana, is a strategic sentinel location for infectious disease surveillance. Ecological pressures such as deforestation, artisanal gold mining, and high human mobility contribute to complex transmission dynamics of arboviruses, bacterial infections, and other pathogens. This study aims to characterize the etiologies of acute febrile illness (AFI) reported in Amapa State in 2018-2020, focusing on arbovirus circulation, bacterial contributions, and emerging pathogens. A retrospective analysis was carried out with 727 AFI cases. Laboratory diagnoses were established using molecular and serological assays, with systematic testing for different pathogens. Definitive diagnoses were obtained in 185 individuals (25.4%), yielding 209 positive results and including 23 cases of co-infection. Dengue virus was the predominant etiological agent (n=109, 52%), followed by leptospirosis (n=20, 9.5%), chikungunya virus (n=16, 7.6%), parvovirus B19 (n=16, 7.6%), measles (n=15, 7.1%), zika virus (n=10, 4.8%), mayaro virus (n=1,0.5%), and other bacterial infections (n=5, 2.4%). Isolated cases of hepatitis A and B, malaria, SARS-CoV-2, enterovirus, and acute Chagas disease were also identified. No hepatitis E virus or oropouche cases were detected. Dengue virus was the leading cause of AFI. Leptospirosis, chikungunya virus, and parvovirus B19 were other prevalent and often underrecognized contributors. The detection of additional viruses highlights Amapa State as a potential zone of \"silent expansion\" for emerging arboviruses. Co-detection of multiple pathogens underscores diagnostic complexity in regions with overlapping transmission. Strengthening surveillance, expanding laboratory capacity, and prioritizing differential diagnostics are essential to capture epidemiological dynamics and guide public health interventions.</p>","PeriodicalId":54466,"journal":{"name":"Revista Do Instituto De Medicina Tropical De Sao Paulo","volume":"68 ","pages":"e67"},"PeriodicalIF":1.3,"publicationDate":"2026-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13641766/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149139495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Measles outbreak in a unique sociocultural context: epidemiological investigation and control measures in Northern Brazil, 2025.","authors":"Rebeca Porto Rosa, Rita de Cássia Ferreira Lins, Marcelo Yoshito Wada, Tiara Bruna Teixeira Teodosio, Ana Catarina de Melo Araújo, Amanda Campos Feitosa, Cintia Paula Vieira Carrero, Cinthya Resplandes, Corinto Gomes Dos Santos Júnior, Danielle Menezes de Brito Mota, Elena de Carvalho Cremm Prendergast, Eliana Ribeiro de Oliveira, Gisele Silva Carvalho Luz, Josafá do Nascimento Cavalcante Filho, Lucimeire Neris Sevilha da Silva Campos, Pedro Pereira da Silva Neto, Marli Jerônimo da Silva Rodrigues, Greice Madeleine Ikeda Carmo, Eder Gatti Fernandes, Marielly Reis Resende Sousa, Marilda M Siqueira, Xenia Rawena Lemos, Suelen Soares da Silva, Elaine da Silva Castro Ferreira, Bruno Silva Milagres, Karen Machado Gomes","doi":"10.1590/S1678-9946202668065","DOIUrl":"10.1590/S1678-9946202668065","url":null,"abstract":"<p><p>After the recertification of measles elimination in Brazil, outbreaks associated with imported cases may occur in pockets of susceptible individuals, including communities with low vaccination coverage. This study describes an outbreak investigation conducted in 2025 in Campos Lindos, Tocantins State, Brazil. In total, 25 cases were confirmed, mostly among unvaccinated Old Believers (a traditional community of Russian origin) following viral introduction linked to international travel, with transmission occurring predominantly within the community. Outbreak response measures, including ring vaccination and active case finding, interrupted transmission after 12 weeks with no new cases. The rapid response was effective and reinforces the importance of identifying susceptibility pockets in the population to prevent measles reintroduction.</p>","PeriodicalId":54466,"journal":{"name":"Revista Do Instituto De Medicina Tropical De Sao Paulo","volume":"68 ","pages":"e65"},"PeriodicalIF":1.3,"publicationDate":"2026-10-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13641767/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149139528","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics and outcomes of dengue infection in kidney transplant recipients: an integrative review.","authors":"Natasha de Lima Monteiro, Ana Carolina de Lima, Raquel Silveira Bello Stucchi, Marilda Mazzali, Marcos Vinicius de Sousa","doi":"10.1590/S1678-9946202668059","DOIUrl":"https://doi.org/10.1590/S1678-9946202668059","url":null,"abstract":"<p><p>Dengue is an arbovirus infection caused by the dengue virus, common in tropical and subtropical areas. It is mainly transmitted by bites from infected Aedes aegypti and Ae. albopictus mosquitoes, but donor-derived cases have been reported. In kidney transplant recipients with dengue, immunosuppressive therapy can affect their immune response and disease presentation. This study analyzed the characteristics and outcomes of kidney transplant recipients diagnosed with dengue. An integrative review was conducted, including case reports, series, case-control, and cohort studies. The PubMed/Medline search in August 2025 used this syntax: ((kidney transplantation) OR (renal transplantation)) AND (dengue). The articles were selected by two reviewers, with a third resolving discrepancies. The database search found 72 articles. After removing duplicates, 71 were screened. Overall, 41 articles were excluded because they did not address the study subject. In total, 30 articles underwent full-text review; eight were excluded-seven lacked kidney transplant recipients with dengue and one had insufficient case details on infected cases. This review included 22 studies from dengue-endemic countries regarding infection occurring from days to years after transplant. Bleeding was more common in infections occurring early post-transplant, possibly linking early infection to severe symptoms. The main symptoms were fever, myalgia, and headache, similar to those in immunocompetent hosts. Thrombocytopenia was frequent, likely due to viral infection and immunosuppressive drugs that affect bone marrow function. No studies assessed the effect of dengue on anti-human leukocyte antigen antibodies or on graft rejection. Graft loss was 4%, and most patients recovered from the disease.</p>","PeriodicalId":54466,"journal":{"name":"Revista Do Instituto De Medicina Tropical De Sao Paulo","volume":"68 ","pages":"e59"},"PeriodicalIF":1.3,"publicationDate":"2026-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13623294/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149118626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Septic arthritis caused by Nocardia asiatica: a case report and narrative review.","authors":"Mehmet Yildiz","doi":"10.1590/S1678-9946202668062","DOIUrl":"10.1590/S1678-9946202668062","url":null,"abstract":"<p><p>Nocardia asiatica is a rare opportunistic pathogen typically associated with pulmonary and central nervous system infections; however, musculoskeletal infections are uncommon. We report a case of septic arthritis caused by N. asiatica in a 72-year-old man with a history of chronic obstructive pulmonary disease (COPD) and pneumoconiosis. The patient presented with subacute knee swelling following a recent episode of pneumonia. Gram staining of intraoperative synovial samples revealed branching filamentous organisms, and the isolate was identified as N. asiatica by mass spectrometry. Although the patient was transferred to another center during the initial phase of management, follow-up information obtained after discharge confirmed a favorable clinical recovery without recurrence. Our report contributes to the limited literature on the clinical manifestations, organ tropism, and antimicrobial susceptibility patterns associated with N. asiatica infection.</p>","PeriodicalId":54466,"journal":{"name":"Revista Do Instituto De Medicina Tropical De Sao Paulo","volume":"68 ","pages":"e62"},"PeriodicalIF":1.3,"publicationDate":"2026-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13588563/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149041871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temporal changes in rabies epidemiology in Brazil: an analysis of notifications of suspected and confirmed human rabies cases, 2010-2025.","authors":"João Vitor Engelhardt, Halana do Carmo Silva, Gabriel Campana do Nascimento, Arthur Moraes Lavinas, Beatriz Biancardi de Campos, Eduarda Scárdua Coser, Bruno Vidal Boscaglia, Elinara Ferreira Santos, Sarah Fernandes Teixeira, Mariana Rambaldi do Nascimento, Joamyr Victor Rossoni Júnior, Clairton Marcolongo-Pereira","doi":"10.1590/S1678-9946202668060","DOIUrl":"10.1590/S1678-9946202668060","url":null,"abstract":"<p><p>Human rabies is an invariably fatal encephalitis caused by Lyssavirus species, with near-100% lethality after symptom onset. In Brazil, canine vaccination has markedly reduced urban transmission. However, human deaths continue to occur and are increasingly linked to sylvatic reservoirs, particularly Desmodus rotundus bats. This study describes the epidemiological profile of human rabies in Brazil from 2010 to 2025, focusing on temporal trends, aggressor species, demographics, geographic distribution, and genetic/antigenic variants. This descriptive time-series study used secondary data from the Notifiable Diseases Information System (SINAN/DATASUS): 1,482 notifications from 16 database files. Antigenic variant data were obtained from the Ministry of Health, and spatial distribution was analyzed using QGIS. Of these, 46 (3.1%) were confirmed, and 41 had recorded dates of death in SINAN. Peaks in the notifications of suspected rabies cases occurred in 2017 (n = 228), whereas confirmed cases peaked in 2018 (n = 11), when all infections were attributed to bats, including a cluster of 10 cases in Para. Men accounted for 55.9% of the notifications, and those aged ≥ 60 and 30-39 years were the most affected. Dogs caused 65.6% of the aggressions, but bats predominated among confirmed cases from 2017 onward. Genetic/antigenic variant analysis identified three active sylvatic cycles: AgV3 (D. rotundus), marmoset lineage (Callithrix jacchus), and wild canid lineage (Cerdocyon thous). No confirmed human rabies cases associated with domestic canine lineages or variants have been reported since 2015. These findings show a shift from urban dog-mediated rabies to sylvatic rabies in Brazil.</p>","PeriodicalId":54466,"journal":{"name":"Revista Do Instituto De Medicina Tropical De Sao Paulo","volume":"68 ","pages":"e60"},"PeriodicalIF":1.3,"publicationDate":"2026-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13588562/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149041894","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phenotypic characterization of inducible and constitutive clindamycin resistance in clinical Staphylococcus aureus isolates.","authors":"Manal Rossi, Moussa Benboubker, Salim Belchkar, Ghita Yahyaoui, Mustapha Mahmoud, Bouchra Oumokhtar","doi":"10.1590/S1678-9946202668061","DOIUrl":"10.1590/S1678-9946202668061","url":null,"abstract":"<p><p>Staphylococcus aureus is a major human pathogen causing infections ranging from mild skin infections to life-threatening systemic conditions. Clindamycin has long been used to treat serious Staphylococcus aureus infections due to its pharmacokinetic profile and ability to inhibit toxin production. However, inducible resistance to clindamycin via erythromycin ribosomal methylases encoded by erm genes poses a significant clinical challenge; it often leads to treatment failure and remains undetected by routine antimicrobial susceptibility testing. This cross-sectional study analyzed 120 non-duplicate clinical Staphylococcus aureus isolates from the University Hospital Center of Fez, Morocco. Identification followed standard microbiological methods, and susceptibility testing adhered to the European Committee on Antimicrobial Susceptibility Testing (EUCAST/CA-SFM) 2024 guidelines. Inducible clindamycin resistance was assessed using the D-test, while methicillin resistance was determined by the cefoxitin disk diffusion method. Of the 120 isolates, 50 (41.67%) were resistant to erythromycin. Constitutive macrolide-lincosamide-streptogramin B (MLSB) resistance was detected in 31 isolates (25.83%), inducible MLSB (iMLSB) resistance in 5 isolates (4.17%), and the macrolide-streptogramin B (MS) phenotype in 14 isolates (11.66%). All isolates with inducible clindamycin resistance or the MS phenotype were methicillin-susceptible Staphylococcus aureus (MSSA), while constitutive MLSB resistance was more frequent among methicillin-resistant Staphylococcus aureus (MRSA). Inducible clindamycin resistance, though less prevalent, remains clinically significant and can be readily detected using the D-test. Routine use of the D-test is essential to guide appropriate antimicrobial therapy and prevent clindamycin treatment failure.</p>","PeriodicalId":54466,"journal":{"name":"Revista Do Instituto De Medicina Tropical De Sao Paulo","volume":"68 ","pages":"e61"},"PeriodicalIF":1.3,"publicationDate":"2026-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13588561/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149041887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}