Antimicrobial Susceptibility to 27 Drugs and the Molecular Mechanisms of Macrolide, Tetracycline, and Quinolone Resistance in Gemella sp.

Gemella is a catalase-negative, facultative anaerobic, Gram-positive coccus that is commensal in humans but can become opportunistic and cause severe infectious diseases, such as infective endocarditis. Few studies have tested the antimicrobial susceptibility of Gemella. We tested its antimicrobial susceptibility to 27 drugs and defined the resistant genes using PCR in 58 Gemella strains, including 52 clinical isolates and six type strains. The type strains and clinical isolates included 22 G. morbillorum, 18 G. haemolysans (GH) group (genetically indistinguishable from G. haemolysans and G. parahaemolysans), 13 G. taiwanensis, three G. sanguinis, and two G. bergeri. No strain was resistant to beta-lactams and vancomycin. In total, 6/22 (27.3%) G. morbillorum strains were erythromycin- and clindamycin-resistant ermB-positive, whereas 4/18 (22.2%) in the GH group, 7/13 (53.8%) G. taiwanensis, and 1/3 (33.3%) of the G. sanguinis strains were erythromycin-non-susceptible mefE- or mefA-positive and clindamycin-susceptible. The MIC90 of minocycline and the ratios of tetM-positive strains varied across the different species-G. morbillorum: 2 µg/mL and 27.3% (6/22); GH group: 8 µg/mL and 27.8% (5/18); G. taiwanensis: 8 µg/mL and 46.2% (6/13), respectively. Levofloxacin resistance was significantly higher in G. taiwanensis (9/13 69.2%) than in G. morbillorum (2/22 9.1%). Levofloxacin resistance was associated with a substitution at serine 83 for leucine, phenylalanine, or tyrosine in GyrA. The mechanisms of resistance to erythromycin and clindamycin differed across Gemella species. In addition, the rate of susceptibility to levofloxacin differed across Gemella sp., and the quinolone resistance mechanism was caused by mutations in GyrA alone.

We Found a Gem in Your Heart: Valvular Heart Disease and Infective Endocarditis Discovered.

Valvular heart disease (VHD) occurs when there is a functional impairment in the valvular apparatus that either obstructs or regurgitates the backflow of blood. When a microorganism resides in those valves, it injures the leaflets and causes complications such as thromboembolic events. Infective endocarditis (IE), usually caused by the Staphylococci and Streptococcus group, is a disease that occurs on the heart valves. Antibiotic resistance is common; thus, culture and sensitivity testing should be done for a more targeted treatment approach. We herein present a rare case of Gemella morbillorum (G. morbillorum) vegetations found in a patient's heart that initially presented with cerebrovascular disease symptoms and underwent heart surgery in the end.

A Rare Pathogen of Bones and Joints: A Systematic Review of Osteoarticular Infections Caused by Gemella morbillorum.

Osteoarticular infections (OAIs) caused by Gemella morbillorum (G. morbillorum) are a rare clinical entity. This study aimed to review all published cases of OAI due to G. morbillorum. A systematic review of PubMed, Scopus, and Cochrane Library was conducted to report the demographic and clinical characteristics, microbiological data, management, and outcome of OAIs caused by G. morbillorum in the adult population. A total of 16 studies reporting on 16 patients were included in this review. Eight patients had arthritis and eight patients had osteomyelitis/discitis. The most reported risk factors were immunosuppression, poor dental hygiene/dental infections, and recent gastrointestinal (GI) endoscopy. Five cases of arthritis occurred in a native joint while three patients had prostheses. The potential source of G. morbillorum infection was documented in more than half of the cases (56%) (most commonly odontogenic and GI sources (25% and 18%, respectively). The knee and hip joints were the most frequently affected joints in patients with arthritis, while the thoracic vertebrae were the most common sites for osteomyelitis/discitis. The blood cultures were positive in three patients with arthritis (37.5%) and five patients with osteomyelitis/discitis (62.5%). Associated endovascular infection was found in five patients with bacteremia. Contiguous spread (adjacent mediastinitis) was documented in two patients with sternal osteomyelitis and thoracic vertebral osteomyelitis. Surgical interventions were performed for 12 patients (75%). Most strains of G. morbillorum were susceptible to penicillin and cephalosporins. All patients with reported outcomes had achieved complete recovery. G. morbillorum is an emerging pathogen for OAIs in certain susceptible populations with specific risk factors. This review reported the demographic, clinical, and microbiological features of OAIs caused by G. morbillorum. A careful evaluation of an underlying infectious focus is warranted to control the source. When G. morbillorum bacteremia is present, it is also necessary to have a high index of suspicion to rule out an associated endovascular infection.

Gemella morbillorum infective endocarditis: A case report and literature review.

Infective endocarditis (IE) caused by Gemella morbillorum is rare. Consequently, little is known about the natural course of endocarditis caused by this pathogen. This report describes the case of a 37-year-old male patient with G. morbillorum endocarditis. The patient was hospitalized for a fever of unknown origin. He complained of intermittent fever of unknown origin for 2 months. He had also undergone root canal therapy for pulpitis a month ago. After admission, the infectious pathogen G. morbillorum was identified using metagenomic next-generation sequence technology. The anaerobic blood culture bottle showed only Gram-positive cocci. Transthoracic echocardiography showed 10 mm vegetation on the aorta, which met the IE diagnostic Duke's criteria, and the patient was diagnosed with G. morbillorum IE. Because no bacterial colonies were formed on the culture, the drug sensitivity test could not be conducted. Ceftriaxone anti-infective drugs are based on careful consideration of the literature and patient. Six days after antibiotic treatment in our department, the patient was discharged from the hospital in stable condition and had no adverse reactions at 1 week of follow-up. To help clinicians better understand the disease of G. morbillorum IE, we also reviewed and discussed the relevant cases published after 2010 when presenting the report.

Acute Hematogenous Periprosthetic Hip Infection by Gemella morbillorum, Successfully Treated with Debridement, Antibiotics and Implant Retention: A Case Report and Literature Review of Osteoarticular Gemella morbillorum Infections.

Gemella morbillorum is a facultative anaerobic, catalase-negative and non-spore forming Gram-positive cocci. It can be found as part of the normal oropharyngeal flora, in the gastrointestinal tract and the female genital tract. However, it can be a causal agent of infections such as endocarditis, meningitis or brain abscesses, and very rarely can cause osteoarticular infections. Herein, a case report of an acute hematogenous prosthetic hip infection caused by Gemella morbillorum, successfully treated with a DAIR and beta-lactam antibiotic therapy, is presented. We provide a literature review of the other orthopedic-related infections caused by this microorganism.

Comparative susceptibility of Gemella morbillorum to 13 antimicrobial agents.

The in vitro activity of 13 antimicrobials against clinical isolates of Gemella morbillorum showed good susceptibility to clindamycin, all beta-lactams agents studied except cefoxitin (MIC90, 4 µg/ml) and fluoroquinolones. There was 36% metronidazole resistance.

Gemella morbillorum- and Capnocytophaga sp.-Related Mycotic Thoracic Aortic Aneurysm and Mediastinal Abscess: An Unusual Case Report, a Treatment Challenge, and a Review of Literature.

A thoracic mycotic aortic aneurysm is an uncommon entity that can complicate mediastinal abscesses. Gemella morbillorum and Capnocytophaga sp. are oral bacteria that are very rarely encountered in this setting, especially when occurring together and with other organisms, posing a difficult treatment challenge per the available guidelines and sensitivities. We present in detail this interesting case of a multi-organism mediastinal abscess and thoracic mycotic aortic aneurysm after a previous esophagogastroduodenoscopic procedure in a 51-year-old female with known achalasia who presented with upper abdominal pain, including a successful surgical and antibiotic treatment regimen and a literature review of the involved topics.

Aortic valve endocarditis by Actinomyces odontolyticus and Gemella morbillorum oral pathogens.

A 56-year-old female with a history of poor dental hygiene and aortic insufficiency status post aortic valve replacement in 2015 presented with chest pain and fevers. She was found to have portal vein thrombosis, colitis, and infective endocarditis with aortic valve thickening. Blood cultures were positive for Actinomyces odontolyticus and Gemella morbillorum. Transesophageal echocardiogram was positive for aortic root thickening. Patient was treated with ceftriaxone and apixaban with full recovery.

Gemella morbillorum endocarditis in a patient with a bicuspid aortic valve.

Gemella morbillorum is one of the rare causative microorganisms of endocarditis. We herein report a case of infective endocarditis in a patient with bicuspid aortic valve caused by G. morbillorum. Infective endocarditis diagnosis was established based on the Modified Duke's criteria. The patient was successfully treated with medical-surgical management.

A case of Gemella morbillorum native valve endocarditis and results of in vitro susceptibility testing.

We present a case of a 48 years old male with Gemella morbillorum native mitral valve endocarditis. Due to poor growth of the organism, antimicrobial susceptibility test (AST) could not be performed using the CLSI approved method. AST was determined using Etest© strips and the patient was successfully treated with mitral valve replacement and intravenous ceftriaxone.

Clinical Implications of Steroid Therapy for Crescentic Glomerulonephritis and Gemella morbillorum-associated Infective Endocarditis.

A 54-year-old man was admitted to our institute with a diagnosis of infective endocarditis (IE) with vegetation on the mitral valve and severe regurgitation due to Gemella morbillorum infection together with renal dysfunction, which was eventually diagnosed as infection-related pauci-immune necrotizing crescentic glomerulonephritis. Given the refractoriness to antibiotics, the persistent activity of nephritis, and repeated cerebral hemorrhaging, we prioritized steroid therapy over early surgical mitral valve replacement. Following steroid therapy, the glomerulonephritis completely improved. Although the administration of steroid therapy in the active phase of IE remains controversial, it might be indicated if comorbid glomerulonephritis is critical.

Gemella morbillorum endocarditis and osteomyelitis in a patient with ankylosing spondylitis.

We report a rare case of Gemella morbillorum endocarditis of the native aortic and mitral valves, and native vertebral osteomyelitis, in a 49-year-old male with HLA-B27 negative ankylosing spondylitis (AKS). G. morbillorum is a rare cause of endocarditis; the incidence of which is unknown. AKS may predispose patients to endocarditis through chronic valvulitis. G. morbillorum bacteremia in patients with AKS should prompt consideration of infective endocarditis and a search for possible portals of entry.

Les auteurs déclarent un rare cas d'endocardite à Gemella morbillorum des valves aortiques et mitrales naturelles et une ostéomyélite des vertèbres naturelles chez un homme de 49 ans atteint de spondylite ankylosante négative au HLA-B27 (SAK). Le G. morbillorum est une rare cause d'endocardite dont on ne connaît pas l'incidence. La SAK peut prédisposer à l'endocardite par une valvulite chronique. La bactériémie à G. morbillorum chez des patients atteints de SAK devrait inciter à envisager rapidement une endocardite infectieuse et à rechercher les voies d'entrée possibles.

Tuberculosis y una Gemella spp: Una combinación indeseable / Tuberculosis and a Gemella spp: An undesirable combination

El género Gemella spp corresponde a cocos gram positivos, anaerobios facultativos, catalasa negativos, no móviles y no formadores de esporas, usualmente comensales de la cavidad oral, que no suelen ser patógenos en pacientes inmunocompetentes. Sin embargo, puede comportarse como germen oportunista en pacientes inmunosuprimidos o con otros factores de riesgo como mala higiene dental, cirugía gastrointestinal, enfermedades metabólicas entre otras, y se asocia con endocarditis, meningitis y en menor medida compromiso pulmonar. La información respecto a la susceptibilidad antimicrobiana es limitada y se asemeja a la de S viridans, por lo que la penicilina y ampicilina son los medicamentos de elección, sin tener claridad en cuanto a duración del tratamiento, usualmente considerando llevar a 4 semanas o hasta el drenaje de la colección. Éste reporte de caso describe una paciente con tuberculosis en tratamiento, que desarrolla una infección invasiva con documentación de empiema y bacteriemia secundaria por Gemella morbillorum, representando la asociación poco común de ésta infección bacteriana con tuberculosis.

Gemella spp. corresponds to gram positive cocci, facultative anaerobes, negative catalase, non mobile and non spore producers, part of colonizing flora of the oral cavity that are not common pathogens in immunocompetent patients. Nevertheless it may behave as an opportunistic germ in immunosuppressed patients or with other risk factors that include bad dental hygiene, bowel surgery, and metabolic diseases among others. It's associated with infections such as endocarditis, meningitis and less frecuently can implicate the lung. The information regarding antimicrobial susceptibility is limited and resembles S viridans, so penicillin and ampicillin are the medications of choice, without being clear about the duration of treatment, usually giving 4 weeks or until collection drain. This case report describes a patient with known tuberculosis diagnosis and under treatment, that develops an invasive infection with empyema and secondary bloodstream infection by Gemella morbillorum, depicting a previously uncommon but described association of this bacterial infection with tuberculosis.

Microbial dysbiosis in irritable bowel syndrome: A single-center metagenomic study in Saudi Arabia.

BACKGROUND: The focus of this study was to explore potential differences in colonic mucosal microbiota in irritable bowel syndrome (IBS) patients compared to a control group utilizing a metagenomic study. METHODS: Mucosal microbiota samples were collected from each IBS patient utilizing jet-flushing colonic mucosa in unified segments of the colon with distilled water, followed by aspiration, during colonoscopy. All the purified dsDNA was extracted and quantified before metagenomic sequencing using an Illumina platform. An equal number of healthy age-matched controls were also examined for colonic mucosal microbiota, which were obtained during screening colonoscopies. RESULTS: The microbiota data on 50 IBS patients (31 females), with a mean age 43.94 ± 14.50 (range19-65), were analyzed in comparison to 50 controls. Satisfactory DNA samples were subjected to metagenomics study, followed by comprehensive comparative phylogenetic analysis. Metagenomics analysis was carried out, and 3.58G reads were sequenced. Community richness (Chao) and microbial structure in IBS patients were shown to be significantly different from those in the control group. Enrichment of Oxalobacter formigenes, Sutterella wadsworthensis, and Bacteroides pectinophilus was significantly observed in controls, whereas enrichment of Collinsella aerofaciens, Gemella morbillorum, and Veillonella parvula Actinobacteria was observed significantly in the IBS cohort. CONCLUSION: The current study has demonstrated significant differences in the microbiota of IBS patients compared to controls.

Intracranial-Intracranial Bypass Using a Y-Shaped Artery Graft for Growing Unruptured Gemella morbillorum Infectious Aneurysm on Artery Supplying Sensory Cortex.

BACKGROUND: Vascular reconstruction is required to treat infectious intracranial aneurysms (IIAs) on arteries supplying the eloquent area. However, extracranial-intracranial bypass is sometimes impossible because IIAs are frequently located distally on arteries and the length of a donor artery is limited. We report a rare case of an unruptured Gemella morbillorum IIA, which was successfully treated by intracranial-intracranial (IC-IC) bypass using a Y-shaped superficial temporal artery (STA) interposition graft. CASE DESCRIPTION: A 52-year-old man presented with heart failure and an unruptured IIA in the right anterior parietal artery because of acute G. morbillorum endocarditis. The patient was treated with urgent replacement of cardiac valves and antibiotic therapy. However, the IIA increased in size during the following 1 month, and therefore was treated surgically to prevent the rupture. End-to-side IC-IC bypass using a Y-shaped STA graft followed by aneurysmal trapping was performed to overcome the limited length of the STA as a donor artery to prevent cerebral ischemia in the artery territory and to avoid direct injury to the sensory cortex adhering tightly to the IIA. Postoperative courses were uneventful, and he recovered from the infectious diseases. CONCLUSIONS: This case suggests that end-to-side IC-IC bypass using a Y-shaped STA graft can be a good option for surgical treatment of IIAs, which are located in eloquent areas.

Gemella morbillorum Cryptogenic Brain Abscess: A Case Report and Literature Review.

A case of cryptogenic brain abscess caused by Gemella morbillorum is reported in a 28-year-old immunocompetent man who presented with seizures and hemiparesis. The patient underwent successful stereotactic drainage of the abscess with complete resolution of symptoms and radiographic evidence of resolution. We report the significant pathogenic potential of a normal commensal rarely identified in neurologic infections.

Gemella morbillorum endocarditis of pulmonary valve:a case report.

BACKGROUND: Pulmonary valve infective endocarditis is a rare finding for endocarditis. Infective endocarditis caused by Gemella morbillorum remains a scanty occurrence. CASE PRESENTATION: This is a case reported of a 28-year-old Chinese male with endocarditis caused by pulmonary valve infection of Gemella morbillorum associated with congenital ventricular septal defect, atrial septal defect and double-chambered right ventricle. The patient presented with fever, shortness of breath, progressively worsening exertional fatigue, dyspnea and weight loss for 3 months. The diagnosis was made with transthoracic echocardiogram, blood cultures, and post-operative pathology. The patient developed congestive heart failure and was managed with aggressive antibiotic therapy followed by surgery. He underwent replacement of the pulmonary valve with an aortic bioprosthetic valve, repair of ventricular septal defect and atrial septal defect, reconstruction of the right ventricular outlflow tract, and excision of vegetations. His postoperative recovery was uneventful. No bacteria were isolated from the excised tissues. He was asymptomatic without recurrence at 3-month follow-up. CONCLUSIONS: The rare pathogen such as Gemella morbillorum can be the cause of infective endocarditis and timely surgical repair is necessary if the infection is refractory or there is progression of congestive heart failure under antibiotic cover.

Rare Bacteria Infecting the Heart and Affecting the Kidney of a Young Child.

Rare bacteria can lead to infective endocarditis, which may lead to renal involvement as severe glomerulonephritis. We report our experience of a 12-year-old child who presented with infective endocarditis and blood culture-grown Gemella morbillorum - a rarely reported bacteria. The clinical picture was further complicated with severe glomerulonephritis. Renal biopsy was suggestive of crescentic glomerulonephritis. The child was managed with antibiotics, steroids, and plasmapheresis and responded well to the treatment. To our knowledge, this is the first report of G. morbillorum endocarditis with immune complex deposition and necrotizing glomerulonephritis in a child.

Gemella morbillorum bacteremia following total laparoscopic hysterectomy for uterine corpus cancer.

Gemella morbillorum, a Gram-positive coccus facultative anaerobe, is part of the normal flora of the mucous membranes of the oropharynx, upper respiratory, gastrointestinal, and female genital tracts. However, this species can also cause serious infection. We herein report on a case of bacteremia, accompanied by peritonitis and pleuritis, in a 46-year-old immunocompetent female following a total laparoscopic hysterectomy for endometrial cancer. The case was successfully treated with antibacterial and antifungal agents.