Mycobacterium gordonae infection in a free-ranging green turtle (Chelonia mydas), Brazil

Mycobacteriosis is a well-known disease that has been reported in a variety of reptiles species. However, the occurrence of mycobacteriosis in sea turtles has been rarely documented, and most reports are from captive-reared animals. A juvenile green turtle (Chelonia mydas) was found stranded in March 2020, in Guanabara Bay, one of the most urbanized and polluted coastal areas in Rio de Janeiro, Southeastern Brazil. The turtle was in fair body condition and exhibited multiple cutaneous fibropapillomas, covering almost 60% of its body. Despite continued medical therapy, the animal died 60 days after initial supportive care. Necropsy revealed granulomatous pneumonia, hydropericardium, small granulomas in the myocardium, liver, spleen, thyroid and brain and caseous exudate in the meninges of the brain. The histopathological analysis showed disseminated granulomatous inflammation in various organs examined during necropsy. Intrahistiocytic acid-fast bacteria were observed in the liver, heart, lungs, kidneys, spleen, brain and adrenals. The blood culture collected shortly after the animal was admitted tested positive for Mycobacterium gordonae, after an 8-week incubation period; however, the animal had already died by the time the results were obtained. Postmortem examination confirmed systemic mycobacteriosis, identified as M. gordonae in blood, liver and lung cultures and by PCR amplification of DNA extracts from frozen tissue samples. This is the first report of a disseminated infection caused by M. gordonae in a free-ranging sea turtle. Although the source of this Mycobacterium remains unknown, it could potentially be related to anthropogenic activities (e.g., waste dumping or leakage from landfill sites). Increasing surveillance of Mycobacterium in wild sea turtles is of paramount importance to better understand the role of mycobacterial species as causative agents of infections in marine species

Serological survey of Neospora caninum and Toxoplasma gondii in shelter-housed cats infected with feline immunodeficiency virus, Brazil

Felines play a leading role in the epidemiology of Toxoplasma gondii infection, but there is scarce information about the epidemiology of Neospora caninum, particularly in feline immunodeficiency virus (FIV)-infected cats. Cats seropositive to T. gondii do not usually show symptoms unless they are immunosuppressed, such as FIV-infected cats. The same relationship remains poorly known for N. caninum, although it has been associated with neurological disorders in HIV-infected people. Since FIV-infected cats are prone to develop encephalitis of unknown etiology, this study aimed to evaluate the presence of specific antibodies to T. gondii and N. caninum in a shelter for stray cats naturally infected with FIV. A total of 104 serum samples from cats living in a shelter, located in São Paulo city (Brazil), was assessed for T. gondii and N. caninum specific antibody by indirect fluorescent-antibody test (IFAT). Of the 104 cats, 25 (24%) were infected with FIV and, aside from these, 8 (32%) had antibodies against T. gondii (titers from 16 to 128). Only 1 (4%) of the FIV infected cats had antibodies against N. caninum, which was the first record of coinfection. Among the FIV-naïve cats, 11 (14%) were positive for T. gondii (titers from 16 to 256) and only 1 (1.2%) had antibodies against N. caninum. Serologically positive reactions to T. gondii and N. caninum were not correlated with age or sex (p>0.05), and there was no correlation between FIV and the occurrence of anti-T. gondii or anti-N. caninum antibodies (p>0.05). Further studies encompassing larger cat populations from different origins and locations are essential to clarify the prevalence of T. gondii and N. caninum antibodies in FIV-positive cats.Os felinos têm um papel importante na epidemiologia da infecção por Toxoplasma gondii, mas pouco se sabe sobre a epidemiologia da infecção por Neospora caninum em gatos, particularmente em gatos infectados com o vírus da imunodeficiência felina (FIV). Gatos soropositivos para Toxoplasma gondii geralmente não apresentam sintomas a não ser que estejam imunossuprimidos, como gatos infectados com FIV. A mesma relação ainda é pouco conhecida para N. caninum, embora tenha sido associada a distúrbios neurológicos em pessoas infectadas pelo HIV. Considerando que gatos infectados com FIV são propensos a desenvolver encefalite de etiologia desconhecida, o presente estudo teve como objetivo avaliar a presença de anticorpos específicos para T. gondii e N. caninum em gatos infectados com FIV. Um total de 104 amostras de soro de gatos residentes em um abrigo na cidade de São Paulo, Brasil, foram avaliadas para a presença de anticorpos contra T. gondii e N. caninum pelo teste de imunofluorescência indireta (RIFI). Dos 104 gatos, 25 (24%) estavam infectados com FIV e destes 8, (32%) tinham anticorpos contra T. gondii (titulação entre 16 e 128). Apenas 1 (4%) dos gatos infectados com FIV apresentava anticorpos contra N. caninum, sendo este o primeiro registro dessa coinfecção. Entre os gatos não infectados com FIV, 11 (14%) foram positivos para T. gondii (titulação entre 16 e 256) e apenas 1 (1,2%) tinha anticorpos contra N. caninum. A reação sorologicamente positiva para T. gondii e N. caninum não foi correlacionada com a idade ou sexo (p> 0,05), nem houve correlação entre FIV e ocorrência de anticorpos para T. gondii ou N. caninum (p> 0,05). Estudos subsequentes abrangendo populações maiores de gatos de diferentes origens e locais são essenciais para esclarecer a prevalência de anticorpos contra T. gondii e N. caninum em animais acometidos por FIV.

One Health Spread of 16S Ribosomal RNA Methyltransferase-Harboring Gram-Negative Bacterial Genomes: An Overview of the Americas

Aminoglycoside antimicrobials remain valuable therapeutic options, but their effectiveness has been threatened by the production of bacterial 16S ribosomal RNA methyltransferases (16S-RMTases). In this study, we evaluated the genomic epidemiology of 16S-RMTase genes among Gram-negative bacteria circulating in the American continent. A total of 4877 16S-RMTase sequences were identified mainly in Enterobacterales and nonfermenting Gram-negative bacilli isolated from humans, animals, foods, and the environment during 1931–2023. Most of the sequences identified were found in the United States, Brazil, Canada, and Mexico, and the prevalence of 16S-RMTase genes have increased in the last five years (2018–2022). The three species most frequently carrying 16S-RMTase genes were Acinetobacter baummannii, Klebsiella pneumoniae, and Escherichia coli. The armA gene was the most prevalent, but other 16S-RMTase genes (e.g., rmtB, rmtE, and rmtF) could be emerging backstage. More than 90% of 16S-RMTase sequences in the Americas were found in North American countries, and although the 16S-RMTase genes were less prevalent in Central and South American countries, these findings may be underestimations due to limited genomic data. Therefore, whole-genome sequence-based studies focusing on aminoglycoside resistance using a One Health approach in low- and middle-income countries should be encouraged

Cytopathology of cutaneous and subcutaneous neoplasms in feline species: a retrospective study

It is estimated that a quarter of all feline neoplasms affect the integumentary system. Cytological examination is of admirable importance for detection of neoplasms in companion animals, being considered a simple and non-invasive method. To date, there are limited information regarding the prevalence of feline skin cancer as well as the use of cytopathology as a diagnostic tool. In this sense, the study aimed to characterize cutaneous and subcutaneous tumors in 192 cats from the archives of a private clinic in São Paulo-SP, Brazil, specialized in the care of felines. Data regarding the animal (breed definition, sex, and age group) and tumor characteristics (biological behavior, cytomorphological category of neoplasm, and cytological suggestion for neoplasm) were obtained in a five-year period. A 95% confidence interval (CI) was estimated to verify the statistical difference between the animal and tumor characteristics. The chi-square test was carried out to verify the association between the tumor biological behavior and animal variables, as well as other tumor characteristics. Most cats were mixed breed and aged 11 to 15 years. Malignant tumors were predominant. A statistical association was observed between cytomorphological category of neoplasm and biological behavior (p<0.001). Mesenchymal (24.5%) and epithelial tumors (25%) presented the highest frequency among those benign and malignant, respectively. The cytological suggestion for neoplasm was also statistically associated with biological behavior (p<0.001). The highest percentage of occurrence of benign and malignant tumors consisted of lipomas (22.9%) and sarcomas (19.3%), respectively

Prevalence, clinical and epidemiological features of feline hyperthyroidism at a veterinary teaching hospital in Brazil: a retrospective study

The hyperthyroidism is the most frequently endocrinopathy in cats. The increasing number of diagnoses over time is due to the greater familiarity with the disease and the development of increasingly sensitive diagnostic tools available. This study aimed to retrospectively evaluate the prevalence, clinical characteristics and risk factors of hyperthyroidism in cats admitted at one of the largest veterinary teaching hospital in Brazil. Between 2002 and 2007, 234 cats were admitted to the veterinary teaching hospital of the University of São Paulo, Brazil. Total thyroxine (T4t) serum concentration was measured from all cats. Also analyzed the medical charts of cats. Of the 234 cats, 26 (11.1%) were considered hyperthyroid (T4t =3.8 µg/dL). Of hese 26 cats, only two (7.7%) were initially diagnosed as hyperthyroid. The age of cats ranged from 6 to 27 years old (13.1 ± 4.5 years). Twelve patients (46.2%) were female and 14 (53.8%) were male. Eight (30.8%) cats were Siamese, while the others were mixed breed (69.2%). Dry food was the most common food type consumed by cats. There was a high prevalence of hyperthyroid cats with concomitant chronic kidney disease (CKD). This study sheds light on the importance of routinely monitoring feline hyperthyroidism and brings epidemiological and clinical data of this endocrinopathy in cats from one of the largest veterinary teaching hospitals in the country

CD4+ and CD8+ T lymphocyte counts and ratio in cats with chronic gingivostomatitis and naturally infected with feline immunodeficiency virus: a preliminary study

This study aimed to evaluate the CD4+ and CD8+ T lymphocytes counts and CD4+: CD8+ ratio in a colony of cats with chronic gingivostomatitis (CGS). We used forty domestic short-haired cats inhabiting the same colony. Ten cats with CGS were immunodeficiency virus-positive (group IV), and ten with CGS were immunodeficiency virus-negative (group III). As a control, twenty cats without CGS were used: ten cats were immunodeficiency virus-positive (group II) and ten cats were immunodeficiency virus-negative (group I). We employed flow cytometry to count CD4+ and CD8+ T lymphocytes. In cats infected with the immunodeficiency virus, the presence of CD4+ lymphocytes were lower both for animals with and without CGS. Conversely, not immunodeficiency virus-infected cats with CGS had a higher amount of CD4+ when compared to seronegative animals without CGS. The counts of CD8+ T lymphocytes showed no significant difference among cats with CGS, whether infected with immunodeficiency virus or not. The CD4+: CD8+ ratio was only different for group III, which was higher than any other group. No difference was observed for total lymphocyte number and CD8+ among groups. By contrast, mean CD4+ levels were different, with cats from groups III and IV showing higher levels than those from groups I and II. The flow cytometry could be a useful tool for the diagnosis and prognosis of cats with CGS infected by the immunodeficiency virus

Relato de infecção por Dirofilaria immitis com complicações cardiopulmonares agudas em um gato no Nordeste do Brasil

A dirofilariose é uma doença zoonótica causada por Dirofilaria immitis, um nematódeo que parasita cães, principalmente a artéria pulmonar e as câmaras direitas do coração, pulmões e grandes vasos. Este parasita também ocorre ocasionalmente em gatos, geralmente causando uma infecção amicrofilarêmica e assintomática, que pode resultar em doença grave e morte rápida. Neste relato de caso, são apresentados os sinais clínicos agudos e alterações histopatológicas em um gato doméstico do município de Mossoró, Rio Grande do Norte, Brasil, com dirofilariose. A espécie de nematóide, D. immitis, foi confirmada por análises morfológicas e moleculares. Este é o primeiro relato documentado e completo de dirofilariose felina no Nordeste do Brasil.Dirofilariasis is a zoonotic disease caused by Dirofilaria immitis, a nematode found mainly in the pulmonary artery and right chambers of the heart, lungs, and large vessels of dogs. This parasitism also occasionally occurs in cats, causing an amicrofilaremic and asymptomatic infection, resulting in severe illness and rapid death. In this case report, it was described acute clinical signs and histopathological alterations in a domestic cat with heartworm disease from the city of Mossoró, the Rio Grande do Norte, Brazil. The nematode species, D. immitis, was confirmed by morphological and molecular analyses. This is the first documented and full report of feline heartworm disease in northeastern Brazil