Granulicatella adiacens, the Elusive Endocarditis Causative Agent: Highlighting the Challenges Faced by Microbiology Laboratory

@#A 58-year-old man with history of mitral valve prolapse and previous motor vehicle accident presented with one week history of lower back pain and fever. He was initially treated for pyelonephritis and given ceftriaxone. Blood culture grew Granulicatella adiacens after 7 days of incubation. The laboratory then referred the case to infectious disease team in view of possible infective endocarditis. Urgent echocardiogram was done and confirmed the diagnosis. His antibiotic was changed to intravenous benzylpenicillin and gentamicin. Granulicatella adiacens are difficult to be isolated in the laboratory hence they imposed certain challenges in laboratory identification. Most patients with Granulicatella adiacens infective endocarditis present with non-specific symptoms, imposing further challenge in recognizing the condition. These factors posed significant challenges in diagnosing Granulicatella adiacens endocarditis. This case highlighted challenges faced by the laboratories and the need of high index of clinical suspicion and prompt communication to ensure optimum patient care and management.

Granulicatella adiacensinfective endocarditis

Infective endocarditis is an unconventional infectious disease nonetheless life-threatening. A roundabout of 3% to 5% cases of Streptococcalinfective endocarditis is caused by nutritionally variant Streptococci (NVS). Granulicatella species is one of the atypical causes of infective endocarditis. In this context, the authors are disclosing a case of infective endocarditis in an underlying rheumatic heart disease patient, caused by Granulicatella adiacens. The patient had breathlessness for the past four months, on and off fever for two months anew and mid-diastolic murmur with vegetation in aortic valve as appeared by echocardiogram. The blood cultures were tested positive for Granulicatella adiacens. The patient was successfully treated with intravenous vancomycin for a period of six weeks.

Endocarditis infecciosa por granulicatella adiacens: reporte de un caso / Infective endocarditis due to granulicatella adiacens: a case report

ResumenEl diagnóstico de endocarditis infecciosa subaguda causa un reto para el clínico, puesto que puede simular otra entidad que confunde el diagnóstico. La endocarditis por Granulicatella adiacens es poco frecuente, sin embargo es un microorga nismo difícil de aislar y cultivar ya que requiere un medio especial para crecer. El porcentaje de endocarditis con cultivos negativos es alto y este podría estar enmascarando microorganismos no identificados. Se presenta un caso muy intere sante de endocarditis por el germen mencionado, donde el tiempo de diagnóstico y de identificación del microorganismo pudieron ser cruciales en el manejo y desenlace del paciente.

AbstractSubacute infective endocarditis is a challeging diagnosis for the clinician, since it can simulate other entities that confound the final diagnosis. Endocarditis by Granulicatella adiacens is rare, and it is a difficult organism to isolate, because it needs a special culture medium to grow. The percentage of culture - negative endocarditis is high and this could be masking unidentified microorganisms. In the following case report, we present an interesting case of endocarditis, whose diagnosis and the time for microorganism identification may have been crucial in the management and patient outcome.

Infections related to Granulicatella adiacens: Report of two cases and review of literature.

Infections due to nutritionally variant streptococci are diagnosed rarely due to difficulties encountered during identification and isolation. Mortality rate in these infections is high therefore appropriate supplemented media and reliable detection systems should be implemented to isolate these fastidious organisms. Here, we describe two cases of Granulicatella adiacens infections. All microbiologic identifications were made with MALDI‑TOF Vitek MS (BioMerieux, France), and the results confirmed by 16S ribotyping.

Native valve endocarditis and femoral embolism due to Granulicatella adiacens: a rare case report

The fastidious Gram-positive cocci Granulicatella adiacens, previously known as nutritionally variant streptococci (NVS) are unusual but significant cause of endocarditis due to increased mortality and morbidity. Difficulties in reaching correct bacteriological identification, increased resistance to beta-lactam antibiotics and macrolides and complicated clinical course have contributed to problems in management of cases of infective endocarditis caused by this bacterium. We present the first Indian case of endocarditis with arterial embolus by G. adiacens in an elderly male with no preexisting cardiac abnormality.

A Case of Endocarditis due to Granulicatella adiacens / 감염과화학요법

Granulicatella species are nutritionally variant streptococci first described in 1961. Granulicatella species form a part of the normal flora of the oral cavity, genitourinary tract, and intestinal tract. These micro-organisms cause bacteremia or local infections such as endocarditis, central nervous system infections, arthritis, and osteomyelitis. Since isolation of Granulicatella species is difficult, only a few cases of infection caused by this microorganism have been reported. Herein, we report a case of endocarditis caused by Granulicatella adiacens in a 46-year-old patient with ventricular septal defect.

A Case of Granulicatella adiacens Septicemia Identified by 16S rRNA Sequencing Analysis / 대한임상미생물학회지

Granulicatella adiacens is one of the fastidious gram positive cocci previously described as nutritionally variant streptococci due to their requirement of L-cysteine, pyridoxal, or thiol compounds for growth. These bacteria have been identified as significant causative agents of endocarditis, opthalmic infections, and meningitis. We report a case of septicemia caused by G. adiacens in an 80-year-old patient with cholangiocarcinoma. The organism was identified by phenotypic and 16S rRNA sequencing analyses.

A Case of Septicemia by Granulicatella adiacens / 감염과화학요법

Granulicatella adiacens was first described as nutritionally variant streptococci, and named as Streptococcus adjacens and Abiotrophia adiacens. Granulicatella species are flora of oral cavity, upper respiratory, urogenital, and gastrointestinal tracts, and are normal often isolated from patients with infective endocarditis. G. adiacens endocarditis is associated with high mortality, but the species hardly grow in the ordinary growth media. We report a case of septicemia caused by G. adiacens in a 52-year-old woman with liver cirrhosis and chronic renal failure.

A Case of Septicemia by Granulicatella adiacens / 감염과화학요법

Granulicatella adiacens was first described as nutritionally variant streptococci, and named as Streptococcus adjacens and Abiotrophia adiacens. Granulicatella species are flora of oral cavity, upper respiratory, urogenital, and gastrointestinal tracts, and are normal often isolated from patients with infective endocarditis. G. adiacens endocarditis is associated with high mortality, but the species hardly grow in the ordinary growth media. We report a case of septicemia caused by G. adiacens in a 52-year-old woman with liver cirrhosis and chronic renal failure.