Retroperitoneal granuloma in a cat caused by Nocardia brasiliensis resulting in bilateral ureteral entrapment and unilateral hydronephrosis.

Nocardia infections in cats most commonly present as subcutaneous wounds, or less commonly, as pneumonia, purulent pleurisy and disseminated disease. Abdominal involvement is rarely reported, and to date, localised retroperitoneal infection has only been reported in people. This report describes a five-year-old domestic shorthair cat living in Canberra, Australia, that presented with a two-month history of pyrexia and inappetence progressing to anorexia. Ultrasonography showed a large retroperitoneal mass incorporating both ureters. Euthanasia was elected because of the guarded prognosis. Necropsy examination revealed the mass to be comprised of extensive pyogranulomatous inflammation with fibrosis, Splendore-Hoeppli phenomenon and filamentous Gram-positive bacteria. Culture and MALDI-TOF mass spectrometry identified the causative agent as Nocardia brasiliensis. N. brasiliensis is commonly diagnosed as a cause of cutaneous nocardiosis in Australian human patients, but to date has only been reported in one cat from the United States and one dog from Australia. A treatment approach that might have been used in such a case is provided even though the cat's owners elected not to proceed with surgical intervention.

Colestasis, delirium y nocardiosis pulmonar en un varón con lupus eritematoso sistémico de inicio tardío / Cholestasis, delirium and pulmonary nocardiosis in a man with systemic lupus erythematosus of late onset

Resumen Se presenta el caso de un varón de 64 años que fue internado por delirium asociado a ictericia con patrón de colestasis en el hepatograma, y una masa en el pulmón derecho en el contexto de pérdida de peso y síndro me constitucional de 8 meses de evolución. Se realizó punción de la masa pulmonar cuyo cultivo desarrolló colonias blanquecinas identificadas como Nocardia cyria cigeorgica por espectrometría de masas (MALDI-TOF MS). Se llegó al diagnóstico de lupus eritematosos sistémico (LES) por presentar 8 de los criterios de acuerdo con el grupo SLICC 2012 y 24 puntos de acuerdo a los criterios EULAR/ACR 2019. La biopsia hepática mostró leve y variable infiltrado inflamatorio mixto en espacios porta, con ausencia de hepatitis de interfase y presencia de reacción ductular periférica. Se interpretaron estos hallazgos como vincu lados a hepatopatía por LES. El delirium fue interpretado como afectación neuroló gica por LES en base al descarte de otras enfermedades. Recibió tratamiento antibiótico y tras constatarse reducción del tamaño de la masa pulmonar se adminis traron pulsos de ciclofosfamida intravenosa. Evolucionó favorablemente, con normalización del hepatograma y el estado de conciencia, y recuperación del peso en forma progresiva. Al año se lo encontró en buen estado de salud. Justifica el reporte del caso la rara forma de presenta ción del LES de comienzo tardío, así como la nocardiosis pulmonar concomitante sin tratamiento inmunosupre sor previo.

Abstract A case is presented of a 64-year-old male patient who was admitted because of delirium, jaundice, a pattern of cholestasis in the liver profile and a right lung mass in the context of a constitutional syndrome and weight loss in the last eight months. The lung mass was punctured and the culture of the obtained material developed white colonies, identified by mass spectrometry (MALDI-TOF) as Nocardia cyriacigeorgica. Regarding the clinical diagnosis, it was considered as systemic lupus erythematosus (SLE), on the basis of fulfilling 8 criteria according to SLICC 2012 group, and 24 points according to EULAR/ACR 2019. The liver biopsy showed a mixt cellular infiltrate in portal spaces, with absence of interphase hepatitis and presence of peripheral ductular reaction. These findings were interpreted as liver compromise relate to SLE. Delirium was also considered as a neurological mani festation related to SLE on the basis of ruling out other causes. After being treated with antibiotics and documenting a reduction in the size of the lung mass he received cy clophosphamide in intravenous pulses, achieving normal ization of his liver profile and his state of consciousness, and a progressively weight recovering. A year after he was in good health. The report of this case is justified because of the rare presenting form of late onset SLE, as well as the concomi tant pulmonary nocardiosis in the absence of previous immunosuppressant treatment.

[Cholestasis, delirium and pulmonary nocardiosis in a man with systemic lupus erythematosus of late onset]. / Colestasis, delirium y nocardiosis pulmonar en un varón con lupus eritematoso sistémico de inicio tardío.

A case is presented of a 64-year-old male patient who was admitted because of delirium, jaundice, a pattern of cholestasis in the liver profile and a right lung mass in the context of a constitutional syndrome and weight loss in the last eight months. The lung mass was punctured and the culture of the obtained material developed white colonies, identified by mass spectrometry (MALDI-TOF) as Nocardia cyriacigeorgica. Regarding the clinical diagnosis, it was considered as systemic lupus erythematosus (SLE), on the basis of fulfilling 8 criteria according to SLICC 2012 group, and 24 points according to EULAR/ACR 2019. The liver biopsy showed a mixt cellular infiltrate in portal spaces, with absence of interphase hepatitis and presence of peripheral ductular reaction. These findings were interpreted as liver compromise relate to SLE. Delirium was also considered as a neurological manifestation related to SLE on the basis of ruling out other causes. After being treated with antibiotics and documenting a reduction in the size of the lung mass he received cyclophosphamide in intravenous pulses, achieving normalization of his liver profile and his state of consciousness, and a progressively weight recovering. A year after he was in good health. The report of this case is justified because of the rare presenting form of late onset SLE, as well as the concomitant pulmonary nocardiosis in the absence of previous immunosuppressant treatment.

Se presenta el caso de un varón de 64 años que fue internado por delirium asociado a ictericia con patrón de colestasis en el hepatograma, y una masa en el pulmón derecho en el contexto de pérdida de peso y síndrome constitucional de 8 meses de evolución. Se realizó punción de la masa pulmonar cuyo cultivo desarrolló colonias blanquecinas identificadas como Nocardia cyriacigeorgica por espectrometría de masas (MALDI-TOF MS). Se llegó al diagnóstico de lupus eritematosos sistémico (LES) por presentar 8 de los criterios de acuerdo con el grupo SLICC 2012 y 24 puntos de acuerdo a los criterios EULAR/ACR 2019. La biopsia hepática mostró leve y variable infiltrado inflamatorio mixto en espacios porta, con ausencia de hepatitis de interfase y presencia de reacción ductular periférica. Se interpretaron estos hallazgos como vinculados a hepatopatía por LES. El delirium fue interpretado como afectación neurológica por LES en base al descarte de otras enfermedades. Recibió tratamiento antibiótico y tras constatarse reducción del tamaño de la masa pulmonar se administraron pulsos de ciclofosfamida intravenosa. Evolucionó favorablemente, con normalización del hepatograma y el estado de conciencia, y recuperación del peso en forma progresiva. Al año se lo encontró en buen estado de salud. Justifica el reporte del caso la rara forma de presentación del LES de comienzo tardío, así como la nocardiosis pulmonar concomitante sin tratamiento inmunosupresor previo.

Primary cutaneous nocardiosis of the ankle caused by N. brasiliensis: a case report.

Nocardia is a genus of aerobic, Gram-positive bacteria known for their filamentous and branching morphology. N. brasiliensis is the most common species causing cutaneous nocardiosis. We present a 67-year-old woman who developed abscesseson the back of her right ankle after walking barefoot on soil. Cultures from the cutaneous lesions grew N. brasiliensis. Antibiotic therapy with trimethoprim-sulfamethoxazole given for a month provided near-complete resolution of her lesions.

Gastrointestinal dysbiosis induced by Nocardia sp. infection in tilapia.

Nocardiosis has caused high mortalities among fish cultures; however, the effects of Nocardia infections in the fish gastrointestinal microbiota are unknown. In this research, tilapia was infected with Nocardia sp., to analyze the effect of infection on the gastrointestinal microbiota. Tilapia infected with Nocardia sp. reported a 46 % survival (100 % in non-infected). Moreover, the infection caused severe damage to the stomach microbiota, with a loss of diversity and a significant increase of Proteobacteria (94.8 %), resulting in a negative correlation network between Proteobacteria and other important phyla. Nocardia sp. is an emerging pathogen capable of inducing dysbiosis and causing significant mortalities.

Nocardiosis: a single-center experience and literature review.

INTRODUCTION: Nocardiosis is a rare bacterial infection caused by Nocardia spp. However, an increasing incidence has been described whereby data about epidemiology and prognosis are essential. METHODS: A retrospective descriptive study was conducted among patients with positive Nocardia spp. culture, from January 2019 to January 2023, at a Terciary Hospital in Portugal. RESULTS: Nocardiosis was considered in 18 cases with a median age of 63.8-years-old. At least one immunosuppressive cause was identified in 70% of patients. Five patients had Disseminated Nocardiosis (DN). The lung was the most common site of clinical disease (77.8%) and Nocardia was most commonly identified in respiratory tract samples. The most frequently isolated species were Nocardia nova/africana (n = 7) followed by Nocardia cyriacigeorgica (n = 3) and Nocardia pseudobrasiliensis (n = 3). The majority of the patients (94.4%) received antibiotic therapy, of whom as many as 55.6% were treated with monotherapy. The most frequently prescribed antibiotic was trimethoprim-sulfamethoxazole. Selected antimicrobial agents were generally effective, with linezolid and cotrimoxazole (100% Susceptibility [S]) and amikacin (94% S) having the most activity against Nocardia species. The median (IQR) duration of treatment was 24.2 (1‒51.4) weeks for DN; The overall one-year case fatality was 33.3% (n = 6) and was higher in the DN (66.7%). No recurrence was observed. CONCLUSION: Nocardiosis is an emerging infectious disease with a poor prognosis, particularly in DN. This review offers essential epidemiological insights and underscores the importance of gaining a better understanding of the microbiology of nocardiosis. Such knowledge can lead to the optimization of antimicrobial therapy and, when necessary, guide appropriate surgical interventions to prevent unfavorable outcomes.

A case of pulmonary nocardiosis with Nocardia brasiliensis spread from a post-traumatic cutaneous infection in an immunocompetent patient.

Nocardia is an aerobic Gram-positive bacterium found in the environment, including soil and water. Nocardia brasiliensis is reportedly associated with cutaneous infections, and disseminated disease is typically detected in immunocompromised individuals. We present a rare case of disseminated nocardiosis with N. brasiliensis in an immunocompetent patient. An 82-year-old male, who had a left elbow injury 2 months prior to the first visit, presented with bilateral multiple lung nodules. N. brasiliensis was identified in both sputum and pus specimens, we concluded that the N. brasiliensis had spread from the primary cutaneous lesion. The patient was treated with antibiotics and had a favourable clinical course. As the present case report demonstrates, disseminated nocardiosis caused by this species can progress from a primary cutaneous lesion even in immunocompetent individuals, if the initiation of appropriate treatment is delayed. Therefore, careful evaluation is warranted when Nocardia species are detected.

Successful treatment with amoxicillin-clavulanic acid: cutaneous nocardiosis caused by Nocardia brasiliensis.

AIM: To emphasize the role of non-sulfonamides in the treatment of Nocardia infection and reduce the adverse reactions caused by sulfonamides. METHODS: We retrospectively analyzed a case of cutaneous nocardiosis in an immunocompetent individual. The colonies obtained by staining the pus in the lesion with antacid and culturing the agar plates were identified by flight mass spectrometry. The pathogenic identification showed Nocardia brasiliensis infection and the patient was treated with amoxicillin-clavulanic acid. RESULTS: After treatment with amoxicillin and clavulanic acid, the ulcer gradually peeled and crusted, leaving dark pigmentation. The patient has finally recovered. CONCLUSION: Sulfonamides are the first-line antibacterial agents for years in treatment of nocardiosis but are of great toxicity and side effects. This patient was successfully treated with amoxicillin-clavulanic acid and it provided a reference protocol for patients with sulfonamide-resistant Nocardia or sulfonamides intolerance.

Pleural effusion-related Nocardia otitidiscaviarum, Anaplasma platys and Ehrlichia canis coinfection in a dog.

The coinfections by some microorganisms have been related to severe diseases in humans and animals, where immunosuppressive agents favor opportunistic behavior of other pathogens. A 4-month-old, female mixed-breed dog with a two-week history of inappetence, prostration, emaciation, and respiratory distress was admitted at a veterinary hospital in Brazil. Tachycardia, pale mucous membranes, severe respiratory distress, and a large number of ticks (Rhipicephalus sanguineus s.l.) in different body regions were observed at clinical examination. Hematological examination of dog showed leukocytosis, neutrophilia, mild anemia, and thrombocytopenia, whereas unremarkable values in biochemical tests. Thoracic radiography revealed a pleural effusion image. Blood and the pleural fluid (purulent aspect) samples were subjected to qPCR (16S rRNA and dsb genes) and sequencing, which identified Ehrlichia canis and Anaplasma platys coinfection. An aggregate of coccoid-to-branching or long filamentous microorganisms, surrounded by pyogranulomatous inflammatory reaction was seen at the cytology of the pleural fluid. Bacteriological culture of pleural effusion showed colonies compatible with the genus Nocardia, which revealed gram-positive filamentous organisms with a tendency of fragmentation and were identified as Nocardia otitidiscaviarum in mass spectrometry (MALDI-TOF MS). Therapy of N. otitidiscaviarum isolate using levofloxacin (supported by a previous in vitro susceptibility testing) and doxycycline for E. canis and A. platys resulted in complete resolution of the clinical picture. Here, we report for the first time a triple coinfection by Nocardia otitidiscaviarum, A. platys, and E. canis in a dog with pleural effusion, where debilitating or immunosuppressive conditions induced by A. platys and E. canis coinfection probably contributed to the opportunistic behavior of N. otitidiscaviarum.

Molecular identification and antimicrobial resistance pattern of Nocardia isolated from 14 diseased dogs and cats.

Nocardia are ubiquitous, saprophytic and opportunistic bacteria. They cause a set of pyogenic clinical infections in animals and humans, particularly immunocompromised patients, mostly affecting the skin and respiratory tract, with refractoriness to conventional therapy. The most descriptions of nocardial infections in companion animals involve case reports, and there are scarce case series studies focused on canine and feline nocardiosis in which diagnosis has been based on molecular techniques. We investigated epidemiological aspects, clinical findings, in vitro susceptibility profile, and molecular identification of Nocardia using PCR-based method targeted 16S rRNA gene in twelve dogs and two cats. Among dogs were observed cutaneous lesions (8/12 = 67%), pneumonia (3/12 = 25%), and encephalitis (2/12 = 17%), whereas cats developed cutaneous lesions and osteomyelitis. Nocardia and canine morbillivirus coinfection was described in six dogs (6/12 = 50%). A high mortality rate (6/8 = 75%) was seen among dogs. Three dogs (3/4 = 75%) and one cat (1/2 = 50%) with systemic signs (pneumonia, encephalitis, osteomyelitis), and 83% (5/6) of dogs with a history of concomitant morbillivirus infection died. N. nova (5/12 = 42%), N. cyriacigeorgica (3/12 = 25%), N. farcinica (2/12 = 17%), N. veterana (1/12 = 8%), and N. asteroides (1/12 = 8%) species were identified in dogs, whereas N. africana and N. veterana in cats. Among the isolates from dogs, cefuroxime (12/12 = 100%), amikacin (10/12 = 83%), gentamycin (10/12 = 83%), and imipenem (10/12 = 83%) were the most effective antimicrobials, whereas cefuroxime, cephalexin, amoxicillin/clavulanic acid, imipenem, and gentamycin were efficient against isolates from cats. Multidrug resistance was observed in 36% (5/14) of isolates. We describe a variety of Nocardia species infecting dogs and cats, multidrug-resistant ones, and a high mortality rate, highlighting a poor prognosis of nocardiosis in companion animals, particularly among animals systemically compromised or coinfected by canine morbillivirus. Our study contributes to species identification, in vitro antimicrobial susceptibility profile, clinical-epidemiological aspects, and outcome of natural Nocardia-acquired infections in dogs and cats.

Nocardiosis pulmonar y del sistema nervioso central: el alcoholismo como factor de inmunocompromiso / Pulmonary and central nervous system nocardiosis: Alcoholism as an immunocompromising factor

La nocardiosis es una enfermedad de distribución mundial; de forma habitual se encuentra en zonas tropicales y afecta principalmente a pacientes inmunocomprometidos, sin embargo, también existen casos reportados de infección en personas inmunocompetentes. Esta infección es causada por actinomicetos del género Nocardia spp. que son bacterias Gram positivas, saprófitos ambientales. Aunque la exposición a Nocardia spp. es casi universal, solo una pequeña fracción de las personas expuestas desarrollan la enfermedad. Se presenta el caso de un hombre de 47 años, sin dato de inmunosupresión, procedente de un área rural de Boyacá, que consultó por un cuadro clínico de cefalea intensa e intermitente, con parestesias y, finalmente, alteración del estado de conciencia. Se practicó una resonancia magnética cerebral, en la que se evidenció una lesión que ocupaba espacio de localización córtico-subcortical en la región fronto-témporo-parietal izquierda, con efecto compresivo y desplazamiento de las cavidades del sistema ventricular. Se sospechó, inicialmente, una lesión neoplásica o un absceso cerebral. El paciente fue sometido a una resección quirúrgica, y el cultivo de la lesión documentó Nocardia africana/nova; en estudios posteriores, se evidenció un posible foco pulmonar primario. Como único factor de riesgo en el paciente, se documentó alcoholismo. Completó seis semanas de tratamiento antibiótico intrahospitalario con evolución clínica y radiológica, y egresó con plan de un año de terapia antibiótica ambulatoria. Aunque la enfermedad por Nocardia spp. afecta principalmente a pacientes inmunocomprometidos, la "evidencia" clínica demuestra que este microorganismo también puede ser una amenaza para individuos sin los factores de riesgo tradicionales para inmunosupresión.

Nocardiosis is a disease with worldwide distribution. It is usually found in tropical areas and mainly affects immunocompromised patients, however, there are also cases where its infection has been reported in immunocompetent patients. This pathology is caused by bacteria known as Nocardia spp., which are gram-positive microorganisms and environmental saprophytes, and although exposure to Nocardia spp. is almost universal, only a small fraction of exposed people develops the disease. We present the case of a 47-year-old man, with no evidence of immunosuppression, from a rural area of Boyacá, who was admitted due to intense and intermittent headache accompanied by paresthesia and, finally, a decrease in consciousness. A brain magnetic resonance was performed and evidenced a fronto-temporo- occipital space-occupying lesion in the cortico-subcortical region with a compressive effect and displacement of the ventricular system cavities. It was suspected at first a neoplastic lesion or a brain abscess. The lesion was surgically resected, and its culture showed Nocardia africana/nova. In later studies a possible primary pulmonary focus was evidenced. Alcoholism was the only risk factor documented. The patient completed 6 weeks of hospital antibiotic treatment with favorable clinical and radiological evolution and was discharged with a 1-year plan of outpatient antibiotic therapy. Although Nocardia spp. mainly affects immunocompromised patients, evidence shows that this microorganism can also be a threat to individuals without traditional immunosuppression risk factors.

Treatment of refractory localized pulmonary nocardiosis caused by Nocardia mexicana with a combination of medication and surgery.

Pulmonary nocardiosis is a rare disease that is often difficult to cure because of its tendency to recur. Here, we report a case of refractory localized pulmonary nocardiosis caused by Nocardia mexicana. A 60-year-old Japanese woman had recurring pulmonary nocardiosis four times previously and each time she was treated with antibiotics for a sufficient duration; nevertheless, the disease continued to recur, probably because of resistance to antibiotics. As a fifth treatment, we performed middle lobe resection and pre- and post-operative antimicrobial therapy for 6 months. The combination of medication and surgery was useful for treating refractory localized pulmonary nocardiosis.

Pyothorax caused by Nocardia sp. in a cat - Case report.

Nocardiosis is an infection caused by ubiquitous opportunistic bacteria and is rare in felines. In retrospective studies of the infection in the species, pyothorax was found in only about 5% of the cases described, with the most frequent forms being cutaneous and subcutaneous. This report describes Nocardia spp. as an etiologic agent of pyothorax in a feline leukemia virus (FeLV)-positive female cat. A 10-year-old female mixed-breed cat, positive for FeLV, with chronic kidney disease IRIS stage 2, was examined with a severe dyspneic onset, suspected of pleural effusion. It also had skin lesions in the interscapular region. The patient underwent thoracentesis, and a dense, creamy, fetid, and flocculated liquid was collected. Radiography was performed after draining the pleural fluid, which showed images suggestive of atelectasis of the left lung lobes and pneumonia. The collected material was sent for analysis, which found that it was a septic exudate. In addition, it was referred for bacterial culture in a special medium due to suspicion of nocardiosis. Long-term treatment with amoxicillin + clavulanic acid resolved the clinical case.

A nocardiose é uma infecção causada por bactérias oportunistas ubíquas e é rara em gatos. Em estudos retrospectivos da infecção na espécie, o piotórax foi encontrado em apenas cerca de 5% dos casos descritos, sendo as formas mais frequentes a cutânea e a subcutânea. Este relato descreve Nocardia spp. como agente etiológico do piotórax em um gato vírus da leucemia felina (FeLV)-positivo. Um gato mestiço de 10 anos de idade, positivo para o FeLV, com doença renal crônica IRIS estágio 2, foi examinado com dispneia grave, com suspeita de derrame pleural. Apresentava lesões cutâneas na região dorsal entre as escápulas. Após sedação, tricotomia e antissepsia, o paciente foi submetido à toracocentese e coletado líquido denso, cremoso, fétido e floculado. A radiografia foi realizada após drenagem do líquido pleural, que mostrou imagens sugestivas de atelectasia dos lobos pulmonares esquerdos e pneumonia. O material coletado foi encaminhado para análise, que constatou tratar-se de exsudato séptico. Além disso, foi encaminhado para cultura bacteriana em meio especial por suspeita de nocardiose. O tratamento prolongado com amoxicilina + ácido clavulânico foi suficiente para a resolução do caso clínico.

First report of nocardiosis due to Nocardia asteroides in a domestic canary (Serinus canaria domestica) in Mexico

Nocardiosis is a multi-systemic disease that has been reported in several species of birds. It is characterized by the development of granulomatous inflammation in several organs, mainly affecting the respiratory system. An adult male domestic canary (Serinus canaria domestica) weighing 14.5 g was received for examination. Multiple nodules were identified in the epicardium, air sacs, and lungs. Histologically these nodules corresponded to granulomas, in which numerous thin, filamentous branching bacteria were identified. Gram stains of the epicardium, air sacs, and lungs revealed many filamentous branching Gram-positive bacteria. These bacteria were also strongly acid-fast positive by Fite-Faraco stain. PCR end-point analysis and sequencing using total DNA extracted from formalin-fixed paraffin-embedded samples of lungs, heart, and air sacs confirmed the presence of Nocardia asteroides. To the best of the authors' knowledge, this is the first case report of nocardiosis associated with Nocardia asteroides in a Domestic Canary (Serinus canaria domestica) in Mexico.(AU)

Nocardiosis: a single-center experience and literature review

ABSTRACT Introduction: Nocardiosis is a rare bacterial infection caused by Nocardia spp. However, an increasing incidence has been described whereby data about epidemiology and prognosis are essential. Methods: A retrospective descriptive study was conducted among patients with positive Nocardia spp. culture, from January 2019 to January 2023, at a Terciary Hospital in Portugal. Results: Nocardiosis was considered in 18 cases with a median age of 63.8-years-old. At least one immunosuppressive cause was identified in 70% of patients. Five patients had Disseminated Nocardiosis (DN). The lung was the most common site of clinical disease (77.8%) and Nocardia was most commonly identified in respiratory tract samples. The most frequently isolated species were Nocardia nova/africana (n = 7) followed by Nocardia cyriacigeorgica (n = 3) and Nocardia pseudobrasiliensis (n = 3). The majority of the patients (94.4%) received antibiotic therapy, of whom as many as 55.6% were treated with monotherapy. The most frequently prescribed antibiotic was trimethoprim-sulfamethoxazole. Selected antimicrobial agents were generally effective, with linezolid and cotrimoxazole (100% Susceptibility [S]) and amikacin (94% S) having the most activity against Nocardia species. The median (IQR) duration of treatment was 24.2 (1-51.4) weeks for DN; The overall one-year case fatality was 33.3% (n = 6) and was higher in the DN (66.7%). No recurrence was observed. Conclusion: Nocardiosis is an emerging infectious disease with a poor prognosis, particularly in DN. This review offers essential epidemiological insights and underscores the importance of gaining a better understanding of the microbiology of nocardiosis. Such knowledge can lead to the optimization of antimicrobial therapy and, when necessary, guide appropriate surgical interventions to prevent unfavorable outcomes.

Septic arthritis due to Nocardia brasiliensis and a review of nocardiosis as a cause of arthritis.

Bacteria of the genus Nocardia are implicated in several disease processes but are a rare cause of septic arthritis. Typically, the cause of Nocardia septic arthritis is dissemination from a pulmonary infection in an immunocompromised host. Herein we present a case of a 64-year-old male who had received a long course of prednisone for membranous nephropathy and developed a septic arthritis due to Nocardia brasiliensis. He was treated sequentially with trimethoprim-sulfamethoxazole and amoxicillin-clavulanate, linezolid and amoxicillin-clavulanate, tigecycline and amoxicillin-clavulanate, and omadacycline and amoxicillin-clavulanate. To our knowledge, only two prior cases of Nocardia brasiliensis septic arthritis without antecedent trauma to the joint or local skin breakdown have been reported. A review of the literature identified 19 other cases of Nocardia septic arthritis. This case reinforces the need to consider Nocardia infection in the differential diagnosis in the immunocompromised patient with concurrent pulmonary infection and septic arthritis.

Absceso cerebral por Nocardia sp. En un paciente inmunocompetente en el Perú: reporte de caso / Brain abscess due to Nocardia sp. In an immunocompetent patient in Peru: a case report

RESUMEN La nocardiosis cerebral es una entidad rara que ha sido reportada principalmente en inmunosuprimidos, y en la actualidad no se dispone de guías clínicas que recomienden un tratamiento de primera línea. Presentamos el caso de un adulto mayor, inmunocompetente, con cuadro de encefalopatía y hemiparesia izquierda, asociado a lesiones compatibles con absceso cerebral múltiple y sugerente de etiología infecciosa. Recibió, inicialmente, tratamiento para la tuberculosis, absceso bacteriano y toxoplasmosis, sin respuesta clínica favorable. Se inició un tratamiento empírico para la nocardiosis con meropenem y trimetoprim/sulfametoxazol, y se logró mejoría clínica e imagenológica. La ocurrencia de eventos adversos obliga el uso temporal de medicamentos alternativos. Se resaltan algunos criterios a considerar para incluir la nocardiosis en el diagnóstico diferencial en los casos de absceso cerebral múltiple y se mencionan los métodos diagnósticos de laboratorio y los fármacos para iniciar un tratamiento empírico.

ABSTRACT Cerebral nocardia infections is a rare entity, which has been mainly reported in immunosuppressed patients. Currently, there are no clinical guidelines for first-line treatment. Our case refers to an older immunocompetent adult, with encephalopathy and left hemiparesis, associated with lesions compatible with multiple brain abscess and suggestive of infectious etiology. He initially received treatment for tuberculosis, bacterial abscess, and toxoplasmosis, without a favorable clinical response. An empirical treatment for nocardiosis started, by using meropenem and trimethoprim / sulfamethoxazole, and clinical and imaging improvement was achieved. The occurrence of adverse events forces the temporary use of alternative medications. We highlight some criteria for including nocardiosis in the differential diagnosis in cases of multiple brain abscess and mention laboratory diagnostic methods and drugs to initiate empirical treatment.

First evidence of fish nocardiosis in Mexico caused by Nocardia seriolae in farmed red drum (Sciaenops ocellatus, Linnaeus).

Between August and December 2013, the offshore cages of a commercial marine farm culturing red drum Sciaenops ocellatus in Campeche Bay Mexico were affected by an outbreak of an ulcerative granulomatous disease with up to 70% cumulative mortality. Thirty-one adults displaying open ulcers on the skin were submitted for diagnosis. At necropsy, multiple white-yellowish nodules (0.1-0.5 cm in diameter) were present in all internal organs, where the kidney and the spleen were the most severely affected. Histopathology evinced typical systemic granulomatous formations. Gram and Ziehl-Neelsen stains on tissue imprints, bacterial swabs and tissue sections revealed Gram-positive, acid-fast, branching beaded long rod filamentous bacteria. Tissue samples resulted positive for nocardiosis with a Nocardia genus-specific nested PCR. Definite identification at the species level and taxonomic positioning of the fastidious pathogen were achieved through a specific Nocardia seriolae PCR and by sequencing the gyrB gene of pure isolates. After administration of antibiotics during fry production, a posterior follow-up monitoring (from 2014 to 2017) detected mild but recurrent outbreaks of the bacteria with no seasonality pattern. To the extent of our knowledge, this is the first report of piscine nocardiosis in Mexico and the first time this disease is detected in red drum.

[Sporotrichoid nocardiosis by Nocardia brasiliensis]. / Nocardiosis esporotricoide por Nocardia brasiliensis.

Nocardia brasiliensis is a gram-positive, branched, aerobic, acid-resistant, rod-shaped bacillus that inhabits in soil, rotten organic matter and waters. Cutaneous nocardiosis in immunocompetent individuals can manifest in three different forms: actinomycetoma, superficial skin infection or lymphocutaneous infection. A case of an 85-year-old woman with an ulcerated lesion on the back of her left hand with erythematous papules in the lymphatic tract infected by N. brasiliensis is described. The microorganism was presumptively identified by conventional and inexpensive methods for a medium complexity laboratory at the species level. The morphological characteristics of colonies, the mold smell, a positive Kinyoun stain and the presence of aerial mycelium were the key tests to identify the genus. Species level identification was confirmed by mass spectrometry (MALDI-TOF MS). The trimethoprim-sulfamethoxazole treatment was effective as this agent was active in the susceptibility testing.

Diagnosis and treatment of lymphocutaneous dermatosis caused by Nocardia brasiliensis: a case report.

Cutaneous nocardiosis is a skin disease mainly caused by Nocardia brasiliensis and Nocardia asteroides. Here, we report a rare case of lymphocutaneous dermatosis in an 87-year-old Chinese man infected with Nocardia brasiliensis. An 87-year-old Chinese man presented at our hospital after suffering erythema, nodules, abscesses, ulceration, and pain in the left upper limb for 10 days. The patient was initially misdiagnosed as lymphocutaneous sporotrichosis. The results of gram staining, acid-fast staining, mass spectrograph revealed Nocardia brasiliensis and 16S ribosomal RNA (16S rRNA) sequencing of samples showed that the patient had a Nocardia brasiliensis infection. Anti-infective therapy with sulfamethoxazole combined with amoxicillin clavulanate potassium was administered for 10 days, followed by sulfamethoxazole alone for 20 days. After 30 days of treatment, the abscess was treated with repeated pus extraction, debridement of erosion and ulcer, wet compress of povidone iodine solution and spectrum of multi-source instrument. The redness and swelling had subsided, and purulent secretion and ulceration had decreased. Lymphocutaneous nocardiosis can easily be misdiagnosed as sporotrichosis based on its clinical manifestations. However, mass spectrometry analysis showed Nocardia brasiliensis according to the fingerprint of the bacteria and 16S rRNA sequencing to identify bacterial DNA can assist with making a diagnosis. For patients with Nocardia brasiliensis, sulfamethoxazole combined with amoxicillin clavulanate potassium is an effective anti-infective treatment.