Coinfección por Aggregatibacter aphrophilus y SARS-CoV-2 con desenlace fatal / Fatal outcome in coinfection by Aggregatibacter aphrophilus and SARS-CoV-2 / Coinfecção por Aggregatibacter aphrophilus e SARSCoV- 2 com desfecho fatal

Resumen Aggregatibacter aphrophilus es un cocobacilo gram negativo de requerimientos nutricionales exigentes, que obliga al microbiólogo a utilizar métodos de identificación no convencionales. Se comunica el caso de una paciente que fue internada con un cuadro clínico caracterizado por fiebre, cefalea y dificultad respiratoria por COVID-19. De las muestras de hemocultivos se rescataron colonias cocobacilares gram negativas de lento crecimiento, las cuales fueron finalmente identificadas como A. aphrophilus mediante MALDI-TOF MS (Matrix-assisted laser desorption ionization time-of-flight mass spectrometry). Dado que en nuestro medio la identificación de este tipo de gérmenes es dificultosa, es fundamental y se recomienda formar una red de laboratorios que den respuesta a las necesidades diagnósticas y tecnológicas.

Abstract Aggregatibacter aphrophilus is a gram-negative coccobacillus with demanding nutritional requirements, which forces the microbiologist to use unconventional typification methods. The case of a patient who was admitted with a clinical history characterised by fever, headache and respiratory distress due to COVID-19 was reported. Slow-growing gram-negative coccobacillary colonies were recovered from the blood culture samples, which were finally typed as A. aphrophilus using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Identifying this organism is difficult in our setting. As it is considered essential, building a network of laboratories that give response to diagnostic and technological needs is highly recommended.

Resumo Aggregatibacter aphrophilus é um cocobacilo gram-negativo com pedidos nutricionais exigentes, o que obriga o microbiologista a utilizar métodos de tipagem não convencionais. É relatado o caso de um paciente que deu entrada com quadro clínico caracterizado por febre, cefaleia e desconforto respiratório devido à COVID-19. Colônias de cocobacilos gram-negativas de crescimento lento foram recuperadas das amostras de hemoculturas, que foram finalmente identificadas como A. aphrophilus usando MALDI-TOF MS (Matrix-assisted laser desorption ionization time-of-flight mass spectrometry). Devido a que a identificação deste tipo de germes é difícil no nosso meio, considera-se essencial e se recomenda construir uma rede de laboratórios que respondam às necessidades diagnósticas e tecnológicas.

Cardiobacterium hominis Endocarditis in a Healthy Adult - Rare but Not to Be Missed

@#Cardiobacterium hominis is part of HACEK group and an atypical cause of infective endocarditis. It may cause similar clinical presentation to other cause of endocarditis. Establishing the diagnosis is challenging as it is a fastidious organism which rarely affects individual without previous cardiac lesion and requires advanced diagnostic tools for identification of species. A 23-year-old previously healthy man presented with intermittent fever for two months associated with palpitations and lethargy. He had undergone a dental procedure four months before the presenting symptoms. Physical examination revealed a pansystolic murmur best heard over the apex. Three aerobic blood culture bottles were positive and Gram stain consistently showed pleomorphic Gram-negative rods. The organism grew as tiny pin-point opaque colonies on sheep blood agar and chocolate agar after 48 hours of incubation but no growth was seen on MacConkey agar. Unsuccessful identification with VITEK 2 NH and VITEK 2 GN was later confirmed by polymerase chain reaction as C. hominis. He was treated with a six-week course of antibiotics.

Compromiso del sistema nervioso central por Eikenella corrodens: revisión de la literatura médica a propósito de un caso clínico / Commitment of the central nervous system by Eikenella corrodens: literature review about a clinical case

Resumen Se presenta el caso de un paciente de 22 años sin antecedentes mórbidos que desarrolló un absceso cerebral secundario a una endocarditis por Eikenella corrodens. El diagnóstico se estableció mediante la detección por reacción de polimerasa en cadena universal en el líquido de la colección cerebral. La ecocardiografía transesofágica confirmó vegetaciones en la válvula mitral. Requirió la colocación de una derivación ventricular externa por vaciamiento del absceso a ventrículos cerebrales e hidrocefalia secundaria. Recibió 80 días de tratamiento antibacteriano efectivo. Su evolución fue favorable, con resolución completa de la infección verificada con imágenes y ecocardiografía de control. El seguimiento a los siete meses por una disfunción de válvula de drenaje ventrículo-peritoneal no demostró infección.

Abstract We present the case of a 22-year-old patient with no morbid history who developed a brain abscess secondary to endocarditis due to Eikenella corrodens. The diagnosis was established by detecting the microorganism by universal polymerase chain reaction in fluid from the brain collection. Trans-esophageal echocardiogram study confirmed vegetations in the mitral valve. External ventricular shunt placement was required due to emptying of abscess to brain ventricles and secondary hydrocephalus. He received 80 days of effective antibiotic treatment and his evolution was favorable with complete resolution of his infection verified with images and echocardiogram. Follow-up at seven months later due to ventricule-peritoneal drainage valve dysfunction did not confirmed infection.

Aggregatibacter aphrophilus aortic valve infective endocarditis / Endocarditis infecciosa en válvula aórtica por Aggregatibacter aphrophilus

Nowadays, infective endocarditis remains a major cause of morbidity and mortality worldwide and there are concerns related to the increased number of infections associated with virulent agents and medical procedures. We present a case of a homeless man with unknown medical history, admitted for lumbar pain who became confused, hypotensive and tachy cardic, evolving to severe sepsis. His initial investigation was also suggestive of acute myocardial infarction but the transthoracic echocardiogram revealed massive aortic valve vegetation with perivalvular abscess leading to severe aortic regurgitation. The patient died with the final diagnosis of infective endocarditis. Later on the blood cultures was identified Aggregatibacter aphrophilus, an HACEK group agent. This case confirms that, albeit the general favorable outcomes, there are cases of serious infections, especially if the diagnosis and treatment were late.

Hoy día, la endocarditis infecciosa continúa siendo una causa importante de mor-bimortalidad en todo el mundo y es preocupante el aumento del número de infecciones asociadas con agentes virulentos y procedimientos médicos. Presentamos el caso de un indigente con antecedentes médicos desconocidos, ingresado por dolor lumbar, que comenzó a sentirse confuso, hipotenso y taquicárdico. Poco después de su ingreso su estado evolucionó a septicemia grave. Los resultados de las pruebas iniciales también eran indicativos de infarto agudo de miocardio, pero el ecocardiograma transtorácico reveló una vegetación masiva en la válvula aórtica con absceso perivalvular condicionando regurgitación aórtica grave. El paciente murió, con el diagnóstico definitivo de endocarditis infecciosa. Más tarde, en los hemocultivos se identificó Aggregatibacter aphrophilus, un microorganismo del grupo HACEK. Este caso confirma que, a pesar de los resultados favorables en general, hay casos de infecciones graves, sobre todo si el diagnóstico y el tratamiento fueron tardíos.

Prosthetic Valve Endocarditis caused by HACEK Organisms: a Case Report and Systematic Review of the Literature / 감염과화학요법

HACEK is a rare cause of prosthetic valve endocarditis (PVE). We describe 42-year-old male patient who presented with Aggregatibacter aphrophilus PVE and cerebral infarct. A. aphrophilus was isolated from his blood cultures as the sole pathogen, which was confirmed by subsequent 16S rRNA sequencing. He was treated with valve replacement surgery and an 8 week course of pathogen-directed antibiotic therapy and followed for 20 months without recurrence.

A Case of Haemophilus parainfluenzae Endocarditis / 대한임상미생물학회지

The HACEK group of bacteria (Haemophilus parainfluenzae, H. aphrophilus, H. paraphrophilus, Actinobacilus actinomycetemcomitans, Cardiobacterium hominis, Eikenella corodens, and Kingella kingae) are the normal flora of the upper respiratory tract and oropharynx. The organisms infect abnormal cardiac valves, causing subacute native endocarditis or prosthetic valve endocarditis more than one year after valve surgery. Haemophilus species are responsible for only 0.5~1% of all infective endocarditis cases. Embolization occurs in 60% and the mortality rate ranges from 16~45% of cases of infective endocarditis caused by H. parainfluenzae. We experienced a case of infective endocarditis due to H. parainfluenzae in a 37-year-old male admitted with high fever, chills, nausea & vomiting, chest discomfort, and blurred vision. The organism was isolated from a blood culture and was identified as H. parainfluenzae by factor V requirement, negativity at urea, positivity at ornithine decarboxylase, and acid production from glucose and maltose. The patient was treated with antibiotics and symptoms and signs were improved

Two Cases of Haemophilus parainfluenzae endocarditis / 감염과화학요법

HACEK organisms are the normal flora of upper respiratory tract and orophaynx. They infect abnormal cardiac valves, causing subacute native valve endocarditis or prosthetic valve endocarditis more than one year after valve surgery. Haemophilus species are responsible for only 0.5-1% of all infectious endocarditis cases. Embolization occurs in 60% and the mortality rate ranges from 16-45% of cases of infective endocarditis caused by H. parainfluenzae. We report two cases of H. parainfluenzae endocarditis, one of them is a 25-year-old male with tricuspid valve vegetations complicated with pulmonary embolism and the other is a 22-year-old female presented with heart failure.

Two Cases of Haemophilus parainfluenzae endocarditis / 감염과화학요법

HACEK organisms are the normal flora of upper respiratory tract and orophaynx. They infect abnormal cardiac valves, causing subacute native valve endocarditis or prosthetic valve endocarditis more than one year after valve surgery. Haemophilus species are responsible for only 0.5-1% of all infectious endocarditis cases. Embolization occurs in 60% and the mortality rate ranges from 16-45% of cases of infective endocarditis caused by H. parainfluenzae. We report two cases of H. parainfluenzae endocarditis, one of them is a 25-year-old male with tricuspid valve vegetations complicated with pulmonary embolism and the other is a 22-year-old female presented with heart failure.

A Case of Infective Endocarditis Caused by Haemophilus paraphrophilus / 대한임상미생물학회지

Haemophilus paraphrophilus is a normal inhabitant of the naso- and oropharynx and has been rarely reported as a cause of endocarditis. H. paraphrophilus is a slow-growing and fastidious gram-negative bacterium and belongs to the HACEK group. We experienced a case of infective endocarditis due to H. paraphrophilus. The organism was repeatedly isolated from the blood cultures of a 60 year -old patient presenting with high fever, chills, cardiac murmur, and change of mental state. The patient had a history of mitral and tricuspid valve replacements and had been followed up for complications of cirrhosis of liver such as esophageal varix and oral bleeding. The isolate was identified as H. paraphrophilus by the characteristics, including factor V requirement, negative indole, urea and ornithine decarboxylase and acid production from glucose and lactose. Antimicrobial susceptibility testing by the disk diffusion method showed that the organism was susceptible to ampicillin, chloramphenicol, tetracycline, trimethoprim/sulfamethoxazole, cefotaxime, ceftazidime, aztreonam, imipenem, and ciprofloxacin. The patient expired on hospital day 8, probably due to complications of cirrhosis of liver To our knowledge, this is the first case of infective endocarditis caused by H. paraphrophilus in Korea.