Clinicopathological and radiographic features in 40 cats diagnosed with pulmonary and cutaneous Rhodococcus equi infection (2012-2018).

OBJECTIVES: This retrospective study aimed to describe clinical manifestations, diagnostic options, radiological features, therapeutic plans and outcomes for cats infected with Rhodococcus equi. METHODS: Forty cats aged between 2 months and 11 years old (median 6 months) that were definitively diagnosed with rhodococcosis between 2012 and 2018 were recruited in this study. Medical records were reviewed for information on signalment, history, clinical presentation, diagnostic testing, treatment plans and clinical outcomes. RESULTS: Of the 40 cats, 36 showed the pulmonary form of the disease, with 35 (87.5%) presenting with dyspnoea, while four cats presented with only cutaneous lesions. Mean body temperature was 38.7 ± 0.2°C. Dyspnoea was noted in 87.5% of the cats. Leukocytosis (58.3%) with band neutrophilia (83.3%), monocytosis (58.3%) and thrombocytopenia (55.5%) were prominent findings in the haematology reports. Hyperproteinaemia (61.1%) with hypoalbuminaemia (22.2%) and hyperglobulinaemia (63.8%) with a low albumin:globulin ratio (38.9%) were prominent features of blood biochemistry reports. An alveolar-interstitial pattern was noted in 75% of pre-thoracocentesis radiographs. Pleural effusion, hepatomegaly, thoracic lymphadenopathy and atelectasis of any lung lobe were seen in 88.9%, 75%, 41.7% and 36.1% of cats, respectively. Overall, the mortality rate was 67.5% in both forms. CONCLUSIONS AND RELEVANCE: Clinicians should be aware that feline rhodococcosis manifests as a pulmonary disease at a much higher rate than previously reported. Further studies are required to address the epidemiology, pathophysiology, disease management and prognosis of feline rhodococcosis. The role of immunosuppression as a predisposing factor in feline rhodococcosis requires further investigation.

Endocarditis por Rothia aeria / Rothia aeria endocarditis. case report

Resumen Paciente de sexo femenino de 65 años, con antecedentes de hipertensión arterial crónica, resistencia a la insulina, histerectomía total y fractura tibioperonea antigua, es hospitalizada por cuadro febril, sin foco, de 2 meses de evolución, con sospecha de endocarditis por parámetros inflamatorios elevados y soplo diastólico en foco aórtico 2/6. Se estudia con ecocardiograma, transtorácico (ETT) y transesofágico (ETE), que muestra vegetación en velo aórtico coronario izquierdo de 9 mm por 7 mm e insuficiencia aórtica leve, motivo por el cual se toma hemocultivo resultando positivo para Rothia aeria. La paciente evoluciona con embolia de riñón derecho y bazo, y posteriormente, con hemorragia subaracnoidea. Inicia tratamiento antibiótico con ampicilina, vancomicina y gentamicina, con lo cual presenta una evolución satisfactoria y es dada de alta luego de 28 días de hospitalización. Al revisar la literatura, se puede llegar a la conclusión de que la endocarditis por Rothia es extremadamente infrecuente y que, en cuanto al cuadro clínico, tiene tendencia a una forma de presentación subaguda, con presencia de vegetaciones grandes mayores a 10mm y un alto grado de complicaciones neurológicas.

Abstract A 65-year-old female patient, with a history of chronic hypertension, insulin resistance, total histerectomy, and tibioperoneal fracture, is hospitalized for fever of unknown etiology. Basterial endocarditis was suspected due to elevated inflammatory parameters and a 2/6 diastolic murmur present in the aortic focus. Transthoracic and transesophageal echocardiography, showed a 9 mm by 7 mm vegetation in the left coronary aortic leaflet of and mild aortic insufficiency, Blood cultures were positive for Rothia aeria. She developed embolism of the right kidney and spleen, and subsequently, a subarachnoid hemorrhage. Antibiotic therapy was initiated with ampicillin, vancomycin and gentamicin, with a satisfactory evolution being discharged after 28 days of hospitalization. When reviewing the literature, it can be concluded that Rothia endocarditis is extremely rare and that, tends to have a subacute presentation with large vegetations, larger than 10 mm, and a high incidence of neurological complications.

Recurrent obstructive acute pyelonephritis: A rare form of Actinotignum (Actinobaculum) schaalii infection in a HIV-1 infected patient.

Actinobaculum schaalii is a rarely reported, anaerobic, Gram-positive bacterium which role as uropathogen is emerging. We report here the case of a 47 year old HIV-1 infected woman presented with five recurrent episodes of obstructive pyelonephritis in the context of multiple renal stones. No bacteria was found until the fifth episode, during which prolonged urinary cultures as well as 16S rDNA sequencing allowed the diagnosis of A. schaalii infection. She had developed a life-threatening condition with severe renal failure. A right nephrectomy was performed and found that the intrarenal stones were attributed to the antiretroviral therapy. The renal parenchyma corresponded to an end-stage renal disease with chronic pyelonephritis without abcesses or granules. The situation improved after six months of amoxicillin therapy.

Oral Administration of Electron-Beam Inactivated Rhodococcus equi Failed to Protect Foals against Intrabronchial Infection with Live, Virulent R. equi.

There is currently no licensed vaccine that protects foals against Rhodococcus equi-induced pneumonia. Oral administration of live, virulent R. equi to neonatal foals has been demonstrated to protect against subsequent intrabronchial challenge with virulent R. equi. Electron beam (eBeam)-inactivated R. equi are structurally intact and have been demonstrated to be immunogenic when administered orally to neonatal foals. Thus, we investigated whether eBeam inactivated R. equi could protect foals against developing pneumonia after experimental infection with live, virulent R. equi. Foals (n = 8) were vaccinated by gavaging with eBeam-inactivated R. equi at ages 2, 7, and 14 days, or gavaged with equal volume of saline solution (n = 4), and subsequently infected intrabronchially with live, virulent R. equi at age 21 days. The proportion of vaccinated foals that developed pneumonia following challenge was similar among the vaccinated (7/8; 88%) and unvaccinated foals (3/4; 75%). This vaccination regimen did not appear to be strongly immunogenic in foals. Alternative dosing regimens or routes of administration need further investigation and may prove to be immunogenic and protective.

Clinical and echocardiographic findings in an 8 year old Brown Swiss cow with myocardial abscess.

Intramyocardial abscesses are rare in cattle and may lead to unspecific clinical signs. This case report describes the clinical and echocardiographic findings in an 8 year old Brown Swiss cow presented with an intramural myocardial abscess. The main clinical findings were anorexia, drop in milk yield, fever, tachycardia, and hyperfibrinogenemia. Neither heart murmurs nor cardiac arrhythmias were present on auscultation. Transthoracic echocardiographic examination revealed a prominent intramural mass embedded in the left ventricular free wall and bulging into the lumen of the left ventricle. Diagnosis was confirmed at necropsy. A culture of the abscess grew Trueperella pyogenes.

A novel cause of community-acquired pneumonia in a young immunocompetent host.

Diffuse pulmonary infiltrates represent a common problem encountered by pulmonologists. The differential diagnosis is extensive and includes infectious, inflammatory, environmental and malignant conditions. Appropriate evaluation, aside from a thorough history and physical examination, includes serologic, radiographic and procedural elements. We describe a case of a healthy male with diffuse pulmonary infiltrates. Work up revealed a novel infectious etiology. Although this particular microorganism has been described to cause native valve endocarditis, recurrent breast abscesses, osteomyelitis and bacteremia, it has to date not been described as a cause for community acquired pneumonia in immunocompetent hosts.

Rhodococcus equi granulomatous mastitis in an immunocompetent patient.

A 37-year-old immunocompetent woman was evaluated for progressive swelling of her left breast. Magnetic resonance imaging (MRI) showed multiple hypo-intense solid lesions and could not exclude breast cancer. Tissue biopsy was suggestive of granulomatous mastitis without any evidence of malignancy. Culture of the specimen in brain heart infusion broth grew Rhodococcus equi. The patient responded well to combination therapy with ciprofloxacin and azithromycin, and the lesions regressed in follow-up MRI. To the best of our knowledge, this is the first report of R. equi granulomatous mastitis. Accurate identification of this rare pathogen is necessary to provide appropriate treatment in granulomatous mastitis.

Macrolide- and rifampin-resistant Rhodococcus equi on a horse breeding farm, Kentucky, USA.

Macrolide and rifampin resistance developed on a horse breeding farm after widespread use was instituted for treatment of subclinical pulmonary lesions in foals. Resistance occurred in 6 (24%) of 25 pretreatment and 8 (62%) of 13 (62%) posttreatment isolates from affected foals. Drug-resistant isolates formed 2 distinct genotypic clusters.

Influence of Trueperella pyogenes in uterus on corpus luteum lifespan in cycling cows.

To study ovarian responses to long-term intrauterine infusions of Trueperella pyogenes (T. pyogenes), 12 nonlacting Holstein cows were transcervically infused with 10 mL of a bacterial solution (8-19 × 10(8) colony-forming units/mL), and the uteri of another four cows (control) were similarly infused with sterile physiological saline. Infusions were done six times, every 3 days from Days 3 to 18 (Day 0 = day of spontaneous ovulation). Development of ovarian follicles and the CL were monitored with transrectal, real-time ultrasonography. In five of the experimentally infected cows (group A), the CL, which developed after Day 0, regressed without maturing, and the first dominant follicle (DF) ovulated (mean ± SEM interovulatory interval, 8.6 ± 0.5 days). In group A, plasma 13,14-dihydro-15-keto-PGF(2α) (PGFM) concentrations rose sharply on Day 6, but plasma progesterone concentrations did not increase substantially (as in the control) and were maintained at approximately 2.5 ng/mL after the first DF ovulated. In seven of the 12 infected cows (group B), the developing CL which formed after Day 0 matured and the second DF ovulated. However, the CL lifespan was shorter (P < 0.01) and the second DF ovulated earlier than in control (interovulatory interval, 16.0 ± 0.4 days and 22.3 ± 1.9 days; P < 0.01). Although there was no sharp increase in PGFM in group B, it tended to be high between Days 11 and 18. In conclusion, long-term, intrauterine infusions of T. pyogenes caused the CL to regress prematurely or to have a somewhat shorter lifespan because of release of endogenous PGF(2α).

Association between radiographic pattern and outcome in foals with pneumonia caused by Rhodococcus equi.

Our objective was to characterize the association between types of radiographic findings and outcome in foals with pneumonia caused by Rhodococcus equi. Admission lateral thoracic radiographs of 62 foals with culture-confirmed R. equi pneumonia were reviewed retrospectively. A scoring system was developed to individually assess the severity of alveolar pattern, interstitial pattern, tracheobronchial lymphadenopathy, pleural effusion, and the number of nodular opacities and cavitary lesions. Individual scores were added to obtain a total radiographic score ranging from 0 (normal) to 22. Forty-three of 62 foals (69%) survived to discharge. The median total radiographic score of nonsurvivors (14; range, 9-16) was significantly (P = 0.007) higher than that of survivors (11; range, 4-15). Foals with a total radiographic score of greater than or equal to 15 were 6.15 times (95% CI: 1.35 to 28.2) less likely to survive than foals with a lower score (P = 0.019). A multivariate logistic regression model was used to identify the potential associations between specific types of radiographic lesions and outcome. The model was statistically significant (P = 0.002) and correctly classified 75.8% of foals. Only severity of alveolar pattern and number of cavitary lesions made statistically significant contributions to the model. There was no significant association between concurrent isolation of other bacteria along with R. equi and the types or severity of radiographic lesions. Based on the results of this study, severity of alveolar pattern and number of cavitary lesions are the radiographic findings significantly associated with a poor outcome in foals with R. equi pneumonia.

Imaging and pathological findings of AIDS complicated by pulmonary Rhodococcus equi infection.

BACKGROUND: Rhodococcus equi (R. equi) infection commonly occurs in grazing areas, especially in patients with AIDS or with T-lymphocyte immuno-deficiencies. Literature reviews revealed that cases radiologically and pathologically diagnosed of AIDS complicated by R. equi infection are rare. This study aimed to investigate the imaging features and pathological basis of AIDS complicated by pulmonary R. equi infection. METHODS: A total of 13 cases of AIDS complicated by pulmonary R. equi infection were retrospectively analyzed based on their imaging, bacterial culture and pathological data, including 10 cases by chest CT scanning and X-ray radiology and 3 cases by only X-ray radiology. All 13 cases were definitely diagnosed by bacterial culture, including one by CT-guided pulmonary puncture with following H&E staining and periodic acid-Schiff (PAS) staining for diagnostic biopsy and another one by bronchial biopsy with following H&E staining and PAS staining for pathological diagnosis. The imaging findings and the pathological findings of AIDS complicated by pulmonary R. equi infection were compared and evaluated. RESULTS: Totally 9 subjects (70%) had radiological demonstrations of central ball liked high density shadows in unilateral pulmonary hilus areas; 10 (77%), cavities and liquefied levels; 3 (23%), pleural effussion. The foci were found in pulmonary inner zone in 10 subjects (77%) and in pulmonary outer zone in one subject (7%). The pathological findings included intra-alveolar hemorrhage, lymphocyte infiltration and granulation tissue proliferation, which were in line with the pathological process of necrotic pneumonia. After 8-month follow-up of anti-R. equi therapy of these 13 cases, 9 cases had obviously decreased or shrunk pulmonary cavities, one died, one missed follow-up, one completely absorbed foci and one did not receive reexaminations. CONCLUSIONS: The radiological demonstrations of AIDS complicated by pulmonary R. equi infection are central ball liked high density areas in unilateral pulmonary hilus area, parenchymal changes, secondary cavities, ground glass liked changes in the lung fields, nodules and treeinbuds sign, which are characteristic rather than specific.

Sonographic characteristics of intraabdominal abscessation and lymphadenopathy attributable to Rhodococcus equi infections in foals.

The sonographic characteristics of intraabdominal abscesses in 11 foals and intraabdominal lymphadenitis in five foals with Rhodococcus equi infections are presented. Intraabdominal abscesses were usually present in the ventral abdomen adjacent to the ventral body wall, well-marginated, and contained a mixed or complex echo pattern. Lymphadenitis appeared as singular or multiple clusters of lymph nodes of mixed echogenicity adjacent to any portion of the gastrointestinal tract or body wall. Sonographic findings were supported by necropsy examinations, but sonographic measurements consistently underestimated the size of abscess.

Comparison of the clinical, microbiological, radiological and haematological features of foals with pneumonia caused by Rhodococcus equi and other bacteria.

The purpose of this study was to compare the clinical, microbiological, radiological, haematological and cytological features of foals with pneumonia caused by Rhodococcus equi infection and with other bacteria, in order to provide markers for early diagnosis and treatment. A retrospective study of 113 cases of bacterial pneumonia was undertaken. Although there was considerable overlap in the affected populations, foals with R. equi pneumonia were significantly younger and had higher respiratory rates. Radiological evidence of thoracic abscessation had a sensitivity of 71% and a specificity of 85% for the diagnosis of R. equi pneumonia. Foals positive for R. equi also had higher peripheral white cell counts and fibrinogen concentrations than animals not infected with this pathogen. Respiratory rate, fibrinogen concentration and the log of the neutrophil count were retained in the final multivariate analysis. Using microbiological culture as the 'gold standard', identification of Gram-positive coccobacilli in tracheal aspirates was highly specific (91%), but poorly sensitive (35%) for R. equi infection. White cell counts >20,000cells/µL (86% specificity), fibrinogen concentrations >700mg/dL (92% specificity), radiological evidence of thoracic abscessation (85% specificity), and the presence of Gram-positive coccobacilli in tracheal aspirates (91% specificity) in pneumonic foals are highly suggestive of R. equi infection and justify early targeted antimicrobial intervention while awaiting culture results.

[Pneumonia caused by Rhodococcus equi: clinical and radiological findings in 8 AIDS patients]. / Neumonía por Rhodococcus equi: hallazgos clínico-radiológicos en ocho pacientes con sida.

INTRODUCTION: the Rhodococcus equi is one bacterium of the order Actinomycetales. It rarely appears in humans, but the HIV/AIDS epidemic has increased the number of cases and the main affected organ is the lung. It causes pneumonia characterized by a slow clinical and radiological progression. OBJECTIVE: to describe the initial radiological alterations from R. equi infection in 8 AIDS patients, the radiological evolution and the clinical and immunological presentation. METHODS: a retrospective descriptive study of radiological pulmonary images from AIDS patients with respiratory infection due to Rhodococcus equi was conducted. RESULTS: these patients presented with high fever (39 degrees C), cough with expectoration and shortness of breath. Homogeneous opacity was the most frequent radiological presentation (62,5% of cases), located predominantly in the lower lobules. The radiological evolution was characterized by opacity with inner cavitation in 4 cases, fibrosis in 4 cases, and one case showed total recovery of lesions. The CD4+ T-cell count was low in all the patients. The evolution ranged from 2 to 33 months. CONCLUSIONS: the R equi pneumonia diagnosis should be borne in mind when dealing with HIV/AIDS patients with compromised immunological condition and breathing process with radiological manifestation of pulmonary consolidation evolving into cavitation, and torpid and prolonged clinical and radiological evolution.

Arcanobacterium haemolyticum: two case reports.

Two uncommon presentations of Arcanobacterium Haemolyticum infection (sinusitis and pharyngitis) are described, emphasizing the poor response to commonly used antibiotics and the possibility of serious local and systemic complications. The difficulties still encountered in the clinical diagnosis are underlined, since this organism could easily pass unrecognized in bacteriological cultures.

Rhodococcus equi lung infection in an allogeneic hematopoietic stem cell transplant recipient.

In this report, we describe a case of Rhodococcus equi lung infection diagnosed in an allogeneic hematopoietic stem cell transplant with oral graft-versus-host disease 3 months after stem cell infusion. The lung lesion persisted despite an approximate 3 months of vancomycin therapy, but then responded favorably to a combination of intravenous ertapenem at 1 g daily and oral rifampin at 600 mg daily for 1 month. An overview of Rhodococcus infection in transplant recipients is presented. This case and the discussed literature suggest that combination antibiotic therapy is warranted in patients with decreased humoral and cellular immunity.