MICOBACTERIOSE CUTÂNEA FELINA - AS DIFICULDADES DO TRATAMENTO

Introdução: A micobacteriose tegumentar em felinos é incomum na rotina de Clínica Médica em Medicina Veterinária, podendo citar uma série de outros diagnósticos diferenciais e mais típicos. Apesar do Mycobacterium spp. ser um bacilo ácido-resistente, pode ser confundido estruturalmente com fungos e seu diagnóstico é raro. Sabe-se ainda que seu crescimento possui uma variação em meios específicos, o que dificulta ainda mais a solicitação de exames laboratoriais. Origina-se de feridas lacerativas cutâneas, traumáticas ou contaminadas, e o tratamento se faz de maneira complexa e multifatorial, na qual o uso contínuo de antibióticos por semanas ou até meses consegue suprimir tal patógeno. Objetivo: O trabalho tem como objetivo pontuar as possibilidades de tratamento dessa infecção em gatos, discutindo resultados de culturas e antibiogramas juntamente com suas respostas associadas a informações obtidas na literatura. Materiais e Métodos: Foi atendido um felino, fêmea, jovem-adulta de 3 anos que apresentava uma ferida ulcerada em região lateral de fêmur que não cicatrizava há 2 meses, encaminhado de colega Veterinário. Resultados: Através de protocolos de tratamento de feridas, e posteriormente, mesmo após tentativas de excisões cirúrgicas, teve persistências e recidivas. Nos exames de cultura bacteriana e antibiograma, que apresentaram diagnóstico de Mycobacterium spp, houve suscetibilidade a alguns antibióticos, porém após meses de uso, mostraram-se ineficazes. Após ser utilizado dois ciclos de antibióticos sem a esperada eficácia, optou-se por associação de fluorquinilona e tetraciclina, que em literatura, auxiliam na remissão da bactéria, mesmo que no antibiograma fosse “resistente”. Decorreram-se 18 meses dos tratamentos, ressaltando-se que a paciente era positiva do Vírus da Imunodeficiência Felina, o que dificultou no processo de recuperação. Conclusão: No final houve melhora visual das lesões, porém com efeitos nocivos colaterais presentes no paciente, como alterações renais e anemia. A mesmo veio a falecer antes mesmo de acabar este relato.

Noble Pen Shell (Pinna nobilis) Mortalities along the Eastern Adriatic Coast with a Study of the Spreading Velocity

Noble pen shells (Pinna nobilis) along the Eastern Adriatic coast were affected by mass mortalities similarly to the populations across the Mediterranean basin. Samples of live animals and organs originating from sites on Mljet Island on the south and the Istrian peninsula on the north of the Croatian Adriatic coast were analyzed using histology and molecular techniques to detect the presence of the previously described Haplosporidium pinnae and Mycobacterium spp. as possible causes of these mortalities. To obtain more information on the pattern of the spread of the mortalities, a study was undertaken in Mljet National Park, an area with a dense population of noble pen shells. The results of the diagnostic analysis and the velocity of the spread of the mortalities showed a significant correlation between increases in water temperature and the onset of mortality. Moderate to heavy lesions of the digestive glands were observed in specimens infected with H. pinnae. A phylogenetic analysis of the detected Haplosporidium pinnae showed an identity of 99.7 to 99.8% with isolates from other Mediterranean areas, while isolated Mycobacterium spp. showed a higher heterogeneity among isolates across the Mediterranean. The presence of Mycobacterium spp. in clinically healthy animals a few months before the onset of mortality imposes the need for further clarification of its role in mortality events.

Metastatic cholangiocarcinoma mimicking tuberculosis in a cow

Here we describe a metastatic hepatic cholangiocarcinoma (cholangiocellular carcinoma) in a 14-y-old Beefmaster cow that was euthanized because of depression and progressive weight loss. Gross changes included coalescing, white-to-yellow, firm-to-hard nodules with central areas of necrosis and mineralization that effaced much of the hepatic parenchyma, omentum, mesentery, ruminal serosa, and diaphragm. A fresh sample of a hepatic nodule was submitted for a modified acid-fast (MAF) stain during autopsy to rule out tuberculosis. The MAF stain was inconclusive, and the sample was subsequently submitted for a PCR assay for Mycobacterium spp. Histologically, all nodules consisted of a neoplastic proliferation of epithelial cells surrounded by extensive areas of desmoplasia, consistent with a metastatic cholangiocarcinoma. PCR for Mycobacterium spp. was negative. Although the histologic diagnosis in our case was metastatic hepatic cholangiocarcinoma, gross changes were strikingly similar to those described in cases of tuberculosis, highlighting the need to remain vigilant in the identification of zoonotic and suspected foreign animal diseases during autopsy to protect human health.

Sero-diagnosis of tuberculosis in elephants in Maharashtra, India

Tuberculosis is a highly contagious zoonotic disease caused by Mycobacterium spp. A study was conducted to detect the presence of Mycobacterium in captive elephants. A total of 15 captive elephants were screened from various regions in Maharashtra. The blood and serum samples collected were subjected to rapid test kit, BacT/ALERT 3D system, Ziehl-Neelsen (ZN) staining and PCR. All the samples were found seronegative using rapid test kit and whole blood PCR. Whereas, all samples were signalled culture positive in BacT/ALERT 3D system which were further subjected to PCR, only one amplicon was produced of 176bp of RD4 gene (Mycobacterium bovis) and no acid-fast organism was detected upon ZN. Due to the atypical nature of this organism, diagnosis of this disease in elephants using various tests is complicated unlike the diagnostic tests that are validated in domestic animals. Therefore, many tests have sub-optimal sensitivity and specificity in elephants. As TB is a zoonotic disease, transmission can occur between human-livestock-elephants interface. Therefore, the zoos and state forest authority should inculcate a protocol of periodic TB screening for Mahouts and elephants in captivity along with protocol of elephant-visitor interaction, thus helping in conservation of this endangered species in India.

Detection of Free-Living Amoebae and Their Intracellular Bacteria in Borehole Water before and after a Ceramic Pot Filter Point-of-Use Intervention in Rural Communities in South Africa

Free-living amoebae (FLA) are ubiquitous in nature, whereas amoeba-resistant bacteria (ARB) have evolved virulent mechanisms that allow them to resist FLA digestion mechanisms and survive inside the amoeba during hostile environmental conditions. This study assessed the prevalence of FLA and ARB species in borehole water before and after a ceramic point-of-use intervention in rural households. A total of 529 water samples were collected over a five-month period from 82 households. All water samples were subjected to amoebal enrichment, bacterial isolation on selective media, and molecular identification using 16S PCR/sequencing to determine ARB species and 18S rRNA PCR/sequencing to determine FLA species present in the water samples before and after the ceramic pot intervention. Several FLA species including Acanthamoeba spp. and Mycobacterium spp. were isolated. The ceramic pot filter removed many of these microorganisms from the borehole water. However, design flaws could have been responsible for some FLA and ARB detected in the filtered water. FLA and their associated ARB are ubiquitous in borehole water, and some of these species might be potentially harmful and a health risk to vulnerable individuals. There is a need to do more investigations into the health risk of these organisms after point-of-use treatment.

Molecular Characterization of Mycobacterium spp. Isolated from Cattle and Wildlife in Poland

Although Poland is officially tuberculosis (TB) free, meaning that less than 0.1% of her cattle herd is TB-positive, the problem of bovine TB in Poland may be re-emerging: its presence has recently been confirmed in domestic and companion animals, wildlife such as the European bison, and even humans. The aim of this chapter was to review all reports of bovine TB in Poland described to date, with particular emphasis on molecular studies, and determine further research directions. These studies include a range of molecular methods for diagnosis, including genotyping, spoligotyping and MIRU- VNTR; such methods successfully identifies a tuberculosis-positive European bison as the source of wild boar infection in the Bieszczady Mountains based on its spoligotype. This chapter argues that identified trains should be better archived, as such records would allow detailed epidemiological investigations and shed greater light on the activity of Mycobacterium spp. The current epidemiological situation in Poland highlights the need for further studies to determine epidemiological links and confirm possible routes of transmission based on whole genome sequencing; this need is accentuated by the zoonotic potential of such infections and the endangered species at risk.

‘Trained immunity’ from Mycobacterium spp. (environmental or BCG) exposure predicts protection from Coronavirus disease 2019 (COVID-19)

ABSTRACTEndeavors to identify protective variables that could be potentially responsible for reduced COVID-19 impact on certain populations have remained a priority. Multiple attempts have been made to attribute the reduced COVID-19 impact on populations to their bacillus Calmette–Guérin (BCG) vaccination coverage ignoring the fact that the effect of childhood BCG vaccination wanes within the first 5 years of life while most of the COVID-19 cases as well as deaths have been observed in adults especially the aged with comorbidities. Since the supposed desired protection being investigated could come from heterologous ‘trained immunity’ conferred by exposure to Mycobacterium spp. (i.e., environmental and BCG), it is argued that the estimates of the prevalence of ‘trained immunity’ of populations currently available as latent tuberculosis infection (LTBI) of populations would be a better variable to evaluate such assertions. Indeed, when we analyze the European populations (twenty-four) as well as erstwhile East and West Germany populations completely disregarding their BCG vaccination coverage, the populations with higher trained immunity prevalence consistently display reduced COVID-19 impact as compared to their lower trained immunity prevalence neighbors. The incidences, mortality, and interim case fatality rates (i-CFR) of COVID-19 are found negatively correlated with the trained immunity of populations that have comparable underlying confounders not the BCG coverage per se. It is submitted that to decisively arrive at dependable conclusions about the potential protective benefit that can be gained from BCG vaccination in COVID-19, the ongoing/planned randomized controlled trials should consciously consider including measures of trained immunity as - a) all individuals immunized do not respond equally, b) small study groups of higher background trained immunity could fail to indicate any protective effect.

Detection of mycobacteria in coalho cheese sold in Northeastern Brazil

The aim of the present study was to detect and identify Mycobaterium spp. in 50 samples of coalho cheese sold in the Northeast region of Brazil. Of the 50 analyzed samples, 35 were produced by the artisanal process, using raw milk, and 15 originated from industrialized establishments that pasteurize milk. Conventional and real-time nested PCR for the rv2807 gene of the M. tuberculosis complex was performed directly from the 50 analyzed samples. Samples of coalho cheese were grown simultaneously in Stonebrink medium, and conventional PCR was performed from the bacterial isolates with primers that flank differentiation region 4 (DR4), specific to M. bovis, mb400F. Bacterial isolates negative by PCR for RD4 were subjected to PCR for hsp65 of Mycobacterium spp., with subsequent DNA sequencing. The cultures were negative for the M. tuberculosis complex, but two samples (4%) from the artisanal process (with raw milk) exhibited identity with hsp65 of Mycobacterium lehmanii (Sequence ID: KY933786.1, identities: 312/363 [86%]); and Mycobacterium rutilum (sequence ID: LT629971.1, identities: 331/371 [89%]), showing to be indicative environmental contamination. Non-tuberculous mycobacteria are emergent and ubiquitous microorganisms; therefore, they deserve greater attention in the cheese production chain, both in terms of Good Agricultural Practices (GAP) and food Good Manufacturing Practices (GMP).