CASE REPORT OF ABIOTROPHIA DEFECTIVA ENDOPHTHALMITIS AFTER REPEATED INJECTIONS OF DEXAMETHASONE INTRAVITREAL IMPLANT (OZURDEX)

PURPOSE

To present a case of endophthalmitis caused by Abiotrophia defectiva after repeated injections of dexamethasone intravitreal implant (Ozurdex), in a patient already on systemic immunosuppressive therapy, and discuss the management of this challenging situation.

METHODS

Case report and review of literature.

RESULTS

A 70-year-old female patient with history of idiopathic pulmonary fibrosis presented for urgent evaluation due to left eye vision loss and mild discomfort 12 days after receiving her seventh dexamethasone implant injection. Ocular history was pertinent for recurrent macular edema resulting from a remote branch vein occlusion. Twelve days after her last injection, visual acuity decreased from 20/30 to counting fingers at 5 feet. Slit-lamp examination showed anterior chamber cell without fibrinoid membranes or hypopyon. Within hours, the patient's clinical appearance progressed. A vitreous tap followed by intravitreal injection of vancomycin (1 mg/0.1 mL) and ceftazidime (2.25 mg/0.1 mL) was performed. The culture from the vitreous sample revealed heavy growth of A. defectiva. Owing to limited improvement, patient was taken to the operating room, and the presence of a full-thickness scleral defect at the site of most recent dexamethasone implant injection was confirmed. Vitrectomy with removal of implant, closure of all sclerotomies, including nonhealing full-thickness scleral defect, and repeated intravitreal antibiotic injection were performed. At the 3-month follow-up, no inflammation was observed, but visual acuity remained poor.

CONCLUSION

Intravitreal dexamethasone implant-associated endophthalmitis in the setting of systemic immunosuppression is a rare and challenging situation. Both local and systemic immunosuppression may delay wound healing, predisposing to wound leakage and consequent endophthalmitis. Despite repeated intravitreal antimicrobial injection and vitrectomy with implant removal, A. defectiva endophthalmitis carried a poor visual outcome.

Double-Valve Heart Disease and Glomerulonephritis Consequent to Abiotrophia defectiva Endocarditis

Abiotrophia defectiva, a nutritionally deficient streptococcus, is a rare cause of infective endocarditis. It has been associated with hemophagocytic syndrome. We present the first case of A. defectiva infective endocarditis that led to antineutrophil cytoplasmic antibody-associated glomerulonephritis. The patient was a 55-year-old man whose endocarditis affected the mitral and aortic valves. His course was complicated by atrial fibrillation, stroke, and glomerulonephritis. He was successfully treated with antibiotics and dual valve replacement.

Epidemiology, Clinical Features, and Outcome of Infective Endocarditis due to Abiotrophia Species and Granulicatella Species: Report of 76 Cases, 2000-2015

Background

Infective endocarditis (IE) caused by Abiotrophia (ABI) and Granulicatella (GRA) species is poorly studied. This work aims to describe and compare the main features of ABI and GRA IE.

Methods

We performed a retrospective study of 12 IE institutional cases of GRA or ABI and of 64 cases published in the literature (overall, 38 ABI and 38 GRA IE cases).

Results

ABI/GRA IE represented 1.51% of IE cases in our institution between 2000 and 2015, compared to 0.88% of HACEK (Haemophilus, Aggregatibacter, Cardiobacterium, Eikenella, Kingella)-related IE and 16.62% of Viridans group streptococci (VGS) IE. Institutional ABI/GRA IE case characteristics were comparable to that of VGS, but periannular complications were more frequent (P = .008). Congenital heart disease was reported in 4 (10.5%) ABI and in 11 (28.9%) GRA cases (P = .04). Mitral valve was more frequently involved in ABI than in GRA (P < .001). Patient sex, prosthetic IE, aortic involvement, penicillin susceptibility, and surgical treatment were comparable between the genera. New-onset heart failure was the most frequent complication without genera differences (P = .21). Five (13.2%) ABI patients and 2 (5.3%) GRA patients died (P = .23). Factors associated with higher mortality were age (P = .02) and new-onset heart failure (P = .02). The genus (GRA vs ABI) was not associated with higher mortality (P = .23).

Conclusions

GRA/ABI IE was more prevalent than HACEK IE and approximately one-tenth as prevalent as VGS; periannular complications were more frequent. GRA and ABI genera IE presented similar clinical features and outcomes. Overall mortality was low, and related to age and development of heart failure.

Abiotrophia defectiva endarteritis with infective spondylodiscitis in an adult patient with patent ductus arteriosus

Endarteritis is a major complication in patients with patent ductus arteriosus, causing significant morbidity and mortality. We report an adult patient with asymptomatic patent ductus arteriosus and endarteritis involving the main pulmonary artery and secondary infective spondylodiscitis at the L5-S1 intervertebral disc caused by Abiotrophia defectivaA. defectiva, commonly referred to as nutritionally variant streptococci, cannot be identified easily by conventional blood culture techniques from clinical specimens. Its isolation was confirmed by 16S ribosomal RNA sequencing. The patient was successfully managed with a combination of penicillin G and gentamicin, pending surgical repair of the patent ductus arteriosus.

Salivary microbiota and caries occurrence in Mutans Streptococci-positive school children

AIM

To compare the composition of the salivary microbiota in caries-affected vs. caries-free mutans streptococci (MS)- positive children with mixed dentition.

MATERIALS AND METHODS

Twenty eight healthy, 11-12-year-old schoolchildren with high MS counts (>10⊃5 CFU/mL) were included in this study. The children were screened with the Dentocult SM Strip Mutans test (Orion Diagnostica, Espoo, Finland) and examined using the International Caries Detection and Assessment System (ICDAS). The microbial composition of the saliva was assessed using the Human Oral Microbe Identification Microarray (HOMIM). Microbial differences between caries-affected (n=18) and caries-free children (n=10) were compared by Mann-Whitney analysis.

RESULTS

The microbiota of the caries-affected vs. caries-free children was rather similar. Abiotrophia defectiva and Actinomyces meyeri/A. odontolyticus were significantly higher in caries-affected than in caries-free children (p=0.006, 0.046, respectively). Shuttleworthia satelles was significantly higher in caries-free compared to caries-affected children (p=0.031). A. defectiva and A. meyeri/A. odontolyticus correlated positively with caries severity measured by ICDAS Caries Index (p = 0.494, 0.454, 0.400 respectively) while S. satelles was negatively correlated with caries severity (p= -0.489).

CONCLUSIONS

Salivary A. defectiva and A. meyeri/A. odontolyticus and are associated with caries occurrence in MS-positive children with mixed dentition.

[Abiotrophia defectiva: an unusual cause of endocarditis]

This article reports one of the rare cases of Abiotrophia defectiva endocarditis with no underlying valvular condition. A sixty-three years old man was hospitalized because of complicated respiratory sepsis with acute heart failure. Hemocultures and echocardiogram enabled the diagnosis of A. defectiva endocarditis. The clinical course was favorable under combined aminoglycoside and cephalosporin. The patient ultimately required valvular replacement. A. defectiva is a micro-organism part of the Nutritionnaly Variant Streptococci (NVS) associated with a high mortality rate and often resistant to antibiotics. Although A. defectiva is a rare cause of endocarditis, prompt recognition and appropriate antibiotic treatment are essential to clinical course.

Infective endocarditis due to Abiotrophia defectiva and Granulicatella spp. complicated by infectious intracranial cerebral aneurysms: a report of three cases and review of the literature

Nutritionally variant streptococci, now classified as Abiotrophia defectivaor Granulicatella spp., are thought to account for 2 % of all infective endocarditis cases but estimates of their frequency are complicated by changes in nomenclature and difficulties in obtaining positive microbiology cultures. Their growth characteristics and difficulty undertaking antibiotic susceptibility testing may impede optimal antibiotic treatment decisions. We describe three patients with definite infective endocarditis due to these organisms seen at our hospital between 2005 and 2010, all of whom presented with neurological symptoms due to infectious intracranial cerebral aneurysms. We recommend that, for patients with left-sided infective endocarditis due to A. defictiva and Granulicatella spp., clinicians should consider imaging the central nervous system.

Abiotrophia defectiva Endocarditis Complicated by Ventricular Tachycardia

A 78-year-old man was admitted to the authors' hospital with a short history of shortness of breath and pyrexia. He had long-standing moderate mitral regurgitation and stable coronary artery disease. Blood cultures grew Abiotrophia defectiva coccobaccili. Transesophageal echocardiography confirmed the diagnosis of mitral valve endocarditis that necessitated treatment with intravenous benzylpenicillin and gentamicin for six weeks. At nine days after admission the patient developed several episodes of self-limiting monomorphic ventricular tachycardia, without ischemic cardiac pain, associated with hemodynamic compromise requiring treatment with intravenous amiodarone and inotropic support in the Intensive Care Unit. The patient made an uneventful recovery. This case report demonstrates that patients with A. defective endocarditis may be associated with life-threatening ventricular tachycardia, and more so if they have underlying coronary artery disease. Hence, these patients are better managed in the Coronary Care Unit with continuous electrocardiogram monitoring, especially in the early stages of the antibiotic treatment.

Bullous impetigo associated with Abiotrophia defectiva in an immunocompetent adult

Infection of humans by Abiotrophia defectiva, a nutritionally variant streptococcus, most commonly takes the form of endocarditis, though a variety of other manifestations ranging from central nervous system abscesses to orthopaedic infections have been seen. We report here what we believe is the first case of bullous impetigo associated with this organism.

Abiotrophia defectiva infection of a total hip arthroplasty diagnosed by 16S rRNA gene sequencing

We describe a case of a total hip arthroplasty infection caused by Abiotrophia defectiva, identified by 16S rRNA gene sequencing. Removal of the prosthesis followed by antibiotic treatment resulted in a good clinical outcome. 16S rRNA gene sequencing can be a useful tool in diagnosing infection with this fastidious microorganism that can easily be misidentified using phenotypic identification methods.

Phylogenetic group- and species-specific oligonucleotide probes for single-cell detection of lactic acid bacteria in oral biofilms

BACKGROUND

The purpose of this study was to design and evaluate fluorescent in situ hybridization (FISH) probes for the single-cell detection and enumeration of lactic acid bacteria, in particular organisms belonging to the major phylogenetic groups and species of oral lactobacilli and to Abiotrophia/Granulicatella.

RESULTS

As lactobacilli are known for notorious resistance to probe penetration, probe-specific assay protocols were experimentally developed to provide maximum cell wall permeability, probe accessibility, hybridization stringency, and fluorescence intensity. The new assays were then applied in a pilot study to three biofilm samples harvested from variably demineralized bovine enamel discs that had been carried in situ for 10 days by different volunteers. Best probe penetration and fluorescent labeling of reference strains were obtained after combined lysozyme and achromopeptidase treatment followed by exposure to lipase. Hybridization stringency had to be established strictly for each probe. Thereafter all probes showed the expected specificity with reference strains and labeled the anticipated morphotypes in dental plaques. Applied to in situ grown biofilms the set of probes detected only Lactobacillus fermentum and bacteria of the Lactobacillus casei group. The most cariogenic biofilm contained two orders of magnitude higher L. fermentum cell numbers than the other biofilms. Abiotrophia/Granulicatella and streptococci from the mitis group were found in all samples at high levels, whereas Streptococcus mutans was detected in only one sample in very low numbers.

CONCLUSIONS

Application of these new group- and species-specific FISH probes to oral biofilm-forming lactic acid bacteria will allow a clearer understanding of the supragingival biome, its spatial architecture and of structure-function relationships implicated during plaque homeostasis and caries development. The probes should prove of value far beyond the field of oral microbiology, as many of them detect non-oral species and phylogenetic groups of importance in a variety of medical conditions and the food industry.

[Rare endocarditis due to Abiotrophia defectiva. Case report and literature review]

Endocarditis by Abiotrophia defectiva is rare but associated with high rates of complications and mortality. The microbiological identification is challenging. Two cases without preexisting valvulopathy and one case with mitral-aortic involvement are described in the literature. A case of this subacute form of endocarditis, with normal mitral and aortic valves, is reported. Surgery was necessary, and mitral repair and aortic homograft implantation were performed with good 3-month results. In case of subacute endocarditis, especially when etiology is difficult to detect, Abiotrophia defectiva should be suspected.