Doença do disco intervertebral cervical em cães: 28 casos (2003-2008)

O objetivo deste estudo foi identificar cães com doença do disco intervertebral (DDIV) cervical atendidos no Hospital Veterinário Universitário (HVU) da Universidade Federal de Santa Maria (UFSM) entre janeiro de 2003 e outubro de 2008 e obter informações a respeito de raça, sexo, idade, sinais neurológicos, resposta ao tratamento cirúrgico, complicações, tempo de recuperação funcional após a cirurgia e ocorrência de recidiva. Hiperestesia cervical foi observada em todos os cães (n=28). Quanto ao grau de disfunção neurológica foram verificados: grau I (8/28[28,5%]), grau II (3/28 [10,7%]), grau III (5/28[17,8%]) e grau V (12/2 [42,8%]). A duração dos sinais neurológicos antes da cirurgia em sete cães (25%) permaneceu por até 15 dias, em 14 cães (50%) entre 15 e 30 dias e nos outros sete cães (25%) por mais de 30 dias. A recuperação satisfatória e sem recidiva foi observada em todos os cães submetidos ao tratamento cirúrgico e que sobreviveram (n=21). Pode-se concluir que a DDIV cervical em nossa rotina acomete principalmente cães adultos, machos, de raças condrodistróficas e não condrodistróficas, incluindo as de grande porte; a hiperestesia cervical é a principal manifestação clínica; a técnica de fenda ventral promove recuperação funcional satisfatória e sem recidiva; as principais complicações trans-operatórias são a hemorragia do plexo venoso, a bradicardia e a hipotensão; e a duração dos sinais clínicos não interfere no tempo de recuperação pós-operatória dos cães.

Recuperação funcional em cães com doença do disco intervertebral toracolombar sem percepção à dor profunda: 37 casos (2002-2010)

O objetivo deste trabalho foi avaliar a recuperação funcional de 37 cães com diagnóstico de doença do disco intervertebral (DDIV) toracolombar, sem percepção da dor profunda superior a 48 horas e não submetidos ao tratamento cirúrgico. Os dados identificados foram: raça, idade, sexo, localização da lesão, perda da percepção da dor profunda, duração dos sinais clínicos, recuperação funcional, retorno da percepção da dor profunda, recidivas, eutanásias ou morte. Foi observada recuperação funcional em 11 cães (55%), sendo seis deles entre 30 e 60 dias após o início dos sinais clínicos. Dos onze cães que tiveram recuperação funcional satisfatória, dois (18%) não tiveram retorno da percepção à dor profunda. Pode-se concluir que cães com diagnóstico de DDIV sem percepção à dor profunda superior a 48 horas e não submetidos ao tratamento cirúrgico podem apresentar recuperação funcional satisfatória e são necessários, no mínimo, 30 dias do início dos sinais clínicos para estabelecer um prognóstico quanto ao retorno dos movimentos voluntários.

Recuperação funcional de cães paraplégicos com doença do disco intervertebral toracolombar sem percepção à dor profunda submetidos ao tratamento cirúrgico: 15 casos (2006-2010)

O objetivo deste estudo retrospectivo foi avaliar a recuperação funcional de cães paraplégicos sem percepção à dor profunda (PDP) com doença do disco intervertebral (DDIV) toracolombar submetidos à hemilaminectomia dorsolateral. Foram incluídos somente cães com DDIV entre os segmentos da medula espinhal T3 e L3, que estavam paraplégicos sem PDP submetidos à cirurgia descompressiva. Foi observada recuperação funcional satisfatória em 73,3% dos cães (n=11), sendo um, aos cinco dias, sete entre 15 e 30 dias e três acima de 30 dias do procedimento cirúrgico. A duração da perda da PDP antes da cirurgia em cinco cães recuperados foi entre 12 e 48 horas e, em seis cães, acima de 48 horas. Cães paraplégicos sem PDP em decorrência da DDIV toracolombar podem apresentar recuperação funcional satisfatória quando submetidos ao tratamento cirúrgico mesmo sem percepção a dor profunda com tempo superior a 48 horas. Futuras pesquisas serão necessárias para avaliar a eficiência do tratamento cirúrgico, principalmente para aqueles que perderam a PDP acima de 48 horas.

Experimental model of intervertebral disc degeneration by needle puncture in Wistar rats

Animal models of intervertebral disc degeneration play an important role in clarifying the physiopathological mechanisms and testing novel therapeutic strategies. The objective of the present study is to describe a simple animal model of disc degeneration involving Wistar rats to be used for research studies. Disc degeneration was confirmed and classified by radiography, magnetic resonance and histological evaluation. Adult male Wistar rats were anesthetized and submitted to percutaneous disc puncture with a 20-gauge needle on levels 6-7 and 8-9 of the coccygeal vertebrae. The needle was inserted into the discs guided by fluoroscopy and its tip was positioned crossing the nucleus pulposus up to the contralateral annulus fibrosus, rotated 360° twice, and held for 30 s. To grade the severity of intervertebral disc degeneration, we measured the intervertebral disc height from radiographic images 7 and 30 days after the injury, and the signal intensity T2-weighted magnetic resonance imaging. Histological analysis was performed with hematoxylin-eosin and collagen fiber orientation using picrosirius red staining and polarized light microscopy. Imaging and histological score analyses revealed significant disc degeneration both 7 and 30 days after the lesion, without deaths or systemic complications. Interobserver histological evaluation showed significant agreement. There was a significant positive correlation between histological score and intervertebral disc height 7 and 30 days after the lesion. We conclude that the tail disc puncture method using Wistar rats is a simple, cost-effective and reproducible model for inducing disc degeneration.

VEGF receptor expression decreases during lung development in congenital diaphragmatic hernia induced by nitrofen

Changes in vascular endothelial growth factor (VEGF) in pulmonary vessels have been described in congenital diaphragmatic hernia (CDH) and may contribute to the development of pulmonary hypoplasia and hypertension; however, how the expression of VEGF receptors changes during fetal lung development in CDH is not understood. The aim of this study was to compare morphological evolution with expression of VEGF receptors, VEGFR1 (Flt-1) and VEGFR2 (Flk-1), in pseudoglandular, canalicular, and saccular stages of lung development in normal rat fetuses and in fetuses with CDH. Pregnant rats were divided into four groups (n=20 fetuses each) of four different gestational days (GD) 18.5, 19.5, 20.5, 21.5: external control (EC), exposed to olive oil (OO), exposed to 100 mg nitrofen, by gavage, without CDH (N-), and exposed to nitrofen with CDH (CDH) on GD 9.5 (term=22 days). The morphological variables studied were: body weight (BW), total lung weight (TLW), left lung weight, TLW/BW ratio, total lung volume, and left lung volume. The histometric variables studied were: left lung parenchymal area density and left lung parenchymal volume. VEGFR1 and VEGFR2 expression were determined by Western blotting. The data were analyzed using analysis of variance with the Tukey-Kramer post hoc test. CDH frequency was 37% (80/216). All the morphological and histometric variables were reduced in the N- and CDH groups compared with the controls, and reductions were more pronounced in the CDH group (P<0.05) and more evident on GD 20.5 and GD 21.5. Similar results were observed for VEGFR1 and VEGFR2 expression. We conclude that N- and CDH fetuses showed primary pulmonary hypoplasia, with a decrease in VEGFR1 and VEGFR2 expression.

Early neonatal echocardiographic findings in an experimental rabbit model of congenital diaphragmatic hernia

This study aimed to demonstrate that congenital diaphragmatic hernia (CDH) results in vascular abnormalities that are directly associated with the severity of pulmonary hypoplasia and hypertension. These events increase right ventricle (RV) afterload and may adversely affect disease management and patient survival. Our objective was to investigate cardiac function, specifically right ventricular changes, immediately after birth and relate them to myocardial histological findings in a CDH model. Pregnant New Zealand rabbits underwent the surgical procedure at 25 days of gestation (n=14). CDH was created in one fetus per horn (n=16), and the other fetuses were used as controls (n=20). At term (30 days), fetuses were removed, immediately dried and weighed before undergoing four-parameter echocardiography. The lungs and the heart were removed, weighed, and histologically analyzed. CDH animals had smaller total lung weight (P<0.005), left lung weight (P<0.005), and lung-to-body ratio (P<0.005). Echocardiography revealed a smaller left-to-right ventricle ratio (LV/RV, P<0.005) and larger diastolic right ventricle size (DRVS, P<0.007). Histologic analysis revealed a larger number of myocytes undergoing mitotic division (186 vs 132, P<0.05) in CDH hearts. Immediate RV dilation of CDH hearts is related to myocyte mitosis increase. This information may aid the design of future strategies to address pulmonary hypertension in CDH.

Novel retrograde puncture method to establish preperitoneal space for laparoscopic direct inguinal hernia repair with internal ring suturing

The aim of this study was to explore the clinical efficacy of a novel retrograde puncture approach to establish a preperitoneal space for laparoscopic direct inguinal hernia repair with inguinal ring suturing. Forty-two patients who underwent laparoscopic inguinal hernia repair with retrograde puncture for preperitoneal space establishment as well as inguinal ring suturing between August 2013 and March 2014 at our hospital were enrolled. Preperitoneal space was successfully established in all patients, with a mean establishment time of 6 min. Laparoscopic repairs were successful in all patients, with a mean surgical time of 26±15.1 min. Mean postoperative hospitalization duration was 3.0±0.7 days. Two patients suffered from postoperative local hematomas, which were relieved after puncturing and drainage. Four patients had short-term local pain. There were no cases of chronic pain. Patients were followed up for 6 months to 1 year, and no recurrence was observed. Our results demonstrate that preperitoneal space established by the retrograde puncture technique can be successfully used in adult laparoscopic hernioplasty to avoid intraoperative mesh fixation, and thus reduce medical costs.

Clonal types and antimicrobial resistance profiles of methicillin-resistant Staphylococcus aureus isolates from hospitals in south Brazil

In the present study were evaluated the DNA macrorestriction profile and SCCmec types for nine multi-resistant MRSA selected. Also antimicrobial susceptibility testing by disk diffusion method was evaluated for 68 MRSA isolates against 12 antimicrobial agents. The isolates were recovered from blood culture collected from hospitalized patients in three hospitals of Porto Alegre, Brazil. PFGE and PCR for mecA and SCCmec I, II, III, IV types genes were done on selected nine isolates with susceptibility only to vancomycin, teicoplanin and linezolid. Two clone profiles, with five subtypes, were demonstrated among multi-resistant MRSA analyzed. Eight isolates showed harbor SCCmec type III and one isolate was not typeable. The knowledge of SCCmec type, clone and antimicrobial profiles among S. aureus is essential mainly to prevention and control of dissemination of the antimicrobial resistance.

Indications of carbapenem resistance evolution through heteroresistance as an intermediate stage in Acinetobacter baumannii after carbapenem administration

We describe an in vivo evolution of an antimicrobial profile from susceptibility to full-resistance to carbapenems, with heteroresistance as an intermediate stage, in an Acinetobacter baumannii strain. Heteroresistance was characterized by the growth of sub-populations within the susceptibility halo in both disk-diffusion and Etest. PCRs for the main A. baumannii carbapenemases were negative. The exact resistance mechanism, diagnostic methods and clinical relevance of heteroresistance in A. baumannii warrant further investigations. This is the first description of such phenomenon in vivo and the second report of heteroresistance to carbapenems in A. baumannii.

Isolation and antifungal susceptibility testing of Trichosporon asahii in Ceará, Brazil

Trichosporon spp. are yeasts capable of causing invasive disease, which mainly affect immunocompromised patients. A clinical strain of T. asahii was isolated from the blood cultures of patients admitted to the General Hospital of Fortaleza. Susceptibility tests were conducted by disk diffusion and broth microdilution. The isolated strain of T. asahii was resistant to fluconazole. The patient used amphotericin B and caspofungin in order to facilitate the microbiological cure. It was the first isolation and identification of T. asahii in blood culture in Ceará, Brazil.

COMPARISON BETWEEN AUTOMATED SYSTEM AND PCR-BASED METHOD FOR IDENTIFICATION AND ANTIMICROBIAL SUSCEPTIBILITY PROFILE OF CLINICAL Enterococcus spp

Enterococci are increasingly responsible for nosocomial infections worldwide. This study was undertaken to compare the identification and susceptibility profile using an automated MicrosScan system, PCR-based assay and disk diffusion assay of Enterococcus spp. We evaluated 30 clinical isolates of Enterococcus spp. Isolates were identified by MicrosScan system and PCR-based assay. The detection of antibiotic resistance genes (vancomycin, gentamicin, tetracycline and erythromycin) was also determined by PCR. Antimicrobial susceptibilities to vancomycin (30 µg), gentamicin (120 µg), tetracycline (30 µg) and erythromycin (15 µg) were tested by the automated system and disk diffusion method, and were interpreted according to the criteria recommended in CLSI guidelines. Concerning Enterococcus identification the general agreement between data obtained by the PCR method and by the automatic system was 90.0% (27/30). For all isolates of E. faecium and E. faecalis we observed 100% agreement. Resistance frequencies were higher in E. faecium than E. faecalis. The resistance rates obtained were higher for erythromycin (86.7%), vancomycin (80.0%), tetracycline (43.35) and gentamicin (33.3%). The correlation between disk diffusion and automation revealed an agreement for the majority of the antibiotics with category agreement rates of > 80%. The PCR-based assay, the van(A) gene was detected in 100% of vancomycin resistant enterococci. This assay is simple to conduct and reliable in the identification of clinically relevant enterococci. The data obtained reinforced the need for an improvement of the automated system to identify some enterococci.

MOLECULAR IDENTIFICATION AND ANTIMICROBIAL RESISTANCE PATTERN OF SEVEN CLINICAL ISOLATES OF Nocardia spp. IN BRAZIL

Nocardia is a ubiquitous microorganism related to pyogranulomatous infection, which is difficult to treat in humans and animals. The occurrence of the disease is on the rise in many countries due to an increase in immunosuppressive diseases and treatments. This report of cases from Brazil presents the genotypic characterization and the antimicrobial susceptibility pattern using the disk-diffusion method and inhibitory minimal concentration with E-test® strips. In summary, this report focuses on infections in young adult men, of which three cases were cutaneous, two pulmonary, one neurological and one systemic. The pulmonary, neurological and systemic cases were attributed to immunosuppressive diseases or treatments. Sequencing analysis of the 16S rRNA segments (1491 bp) identified four isolates of Nocardia farcinica, two isolates of Nocardia nova and one isolate of Nocardia asiatica. N. farcinica was involved in two cutaneous, one systemic and other pulmonary cases; N. nova was involved in one neurological and one pulmonary case; and Nocardia asiatica in one cutaneous case. The disk-diffusion antimicrobial susceptibility test showed that the most effective antimicrobials were amikacin (100%), amoxicillin/clavulanate (100%), cephalexin (100%) and ceftiofur (100%), while isolates had presented most resistance to gentamicin (43%), sulfamethoxazole/trimethoprim (43%) and ampicillin (29%). However, on the inhibitory minimal concentration test (MIC test), only one of the four isolates of Nocardia farcinica was resistant to sulfamethoxazole/trimethoprim.

AMINOGLYCOSIDE RESISTANCE GENES IN Pseudomonas aeruginosa ISOLATES FROM CUMANA, VENEZUELA

The enzymatic modification of aminoglycosides by aminoglycoside-acetyltransferases (AAC), aminoglycoside-adenyltransferases (AAD), and aminoglycoside-phosphotransferases (APH), is the most common resistance mechanism in P. aeruginosa and these enzymes can be coded on mobile genetic elements that contribute to their dispersion. One hundred and thirty seven P. aeruginosa isolates from the University Hospital, Cumana, Venezuela (HUAPA) were evaluated. Antimicrobial susceptibility was determined by the disk diffusion method and theaac, aadB and aph genes were detected by PCR. Most of the P. aeruginosa isolates (33/137) were identified from the Intensive Care Unit (ICU), mainly from discharges (96/137). The frequency of resistant P. aeruginosaisolates was found to be higher for the aminoglycosides tobramycin and amikacin (30.7 and 29.9%, respectively). Phenotype VI, resistant to these antibiotics, was the most frequent (14/49), followed by phenotype I, resistant to all the aminoglycosides tested (12/49). The aac(6´)-Ib,aphA1 and aadB genes were the most frequently detected, and the simultaneous presence of several resistance genes in the same isolate was demonstrated. Aminoglycoside resistance in isolates ofP. aeruginosa at the HUAPA is partly due to the presence of the aac(6´)-Ib, aphA1 andaadB genes, but the high rates of antimicrobial resistance suggest the existence of several mechanisms acting together. This is the first report of aminoglycoside resistance genes in Venezuela and one of the few in Latin America.

Intrahospital spread of carbapenem-resistant Pseudomonas aeruginosa in a University Hospital in Florianópolis, Santa Catarina, Brazil

INTRODUCTION: Carbapenem-resistant Pseudomonas aeruginosa (CRPA) has been isolated with increasing frequency in Brazilian hospitals. Since June 2003, its detection in a teaching hospital in the city of Florianópolis, Brazil, has increased. This study aimed to investigate the minimal inhibitory concentration (MIC), presence of Metallo-β-lactamase (MβL) and a possible clonal relationship among the isolates. METHODS: The study included 29 CRPA and seven isolates with reduced susceptibility. The MIC was determined by agar-dilution. Detection of MβL was performed by Double Disk Sinergism (DDS) and Combined Disk (CD). The MβL gene was verified by PCR and nucleotide sequence analysis. Epidemiological typing was performed by pulsed-field gel electrophoresis. RESULTS: Among the 29 carbapenem-resistant isolates, polymyxin B presented 100% susceptibility and piperacillin/tazobactam 96.7%. Seventeen (62%) strains were verified as clonal (A clone) and among these, six isolates indicated phenotypically positive tests for MβL and harbored the blaSPM-1 gene. The first CRPA isolates were unrelated to clone A, harbored blaIMP-16 and were phenotypically positive only by CD. CONCLUSIONS: The spread of a high-level of resistance clone suggests cross transmission as an important dissemination mechanism and has contributed to the increased rate of resistance to carbapenems. This study emphasizes the need for continuous surveillance and improved strategies.