Actinomycotic osteomyelitis of a long bone in an immunocompetent adult: a case report and literature review.

BACKGROUND: Actinomycosis is a rare, chronic granulomatous disease caused by Gram-positive anaerobic bacteria that colonize the oral cavity. Cervicofacial actinomycosis is the most frequent clinical presentation of actinomycosis, but hematogenous osteomyelitis at distant sites can occur in rare instance in immunocompromised or pediatric patients, only a few cases have been reported in healthy patients. Here we described a new case of distal femur osteomyelitis caused by Actinomyces in an adult patient who was immunocompetent and had no predisposing factors. CASE PRESENTATION: A woman aged 52 years with no history of trauma presented with severe pain, swelling, and increased local heat in the proximal area of the right knee 3 weeks after she first noticed discomfort. Magnetic resonance imaging showed persistent osteomyelitis of the distal metaphysis and diaphysis of the femur with a multifocal intraosseous abscess pocket. An incision and drainage of the abscess were conducted. The tissue culture, fungus culture, acid fast bacillus (AFB) culture, AFB smear, and tuberculosis polymerase chain reaction test results were negative. A pathologic examination confirmed the presence of actinomycosis. The patient was successfully treated with intravenous penicillin G for 8 weeks followed by oral amoxicillin-clavulanate for 6 weeks with repeated surgical debridement and drainage. After a 5-year follow up, the patient had no signs of recurring infection or complications and she had full range of movement in the affected knee. CONCLUSIONS: Although rare, actinomycotic osteomyelitis can occur in healthy people. Furthermore, actinomycotic osteomyelitis is easily misdiagnosed as tuberculosis in areas with a high prevalence of tuberculosis. To detect and identify the bacteria accurately, pathologic examination should be performed as well as culture tests, because the probability for culture confirmation of actinomycosis is quite low. The initial treatment is vital to a successful outcome without ostectomy or amputation.

Neurological disease may precede lymphadenopathies in Actinomyces europaeus infection.

Actinomyces species are part of the commensal flora of the mucous membranes of the oropharynx, gastrointestinal tract and female genital tract. Actinomyces europaeus is a short, nonmotile, facultative anaerobic rod first described in 1997, susceptible in vitro to a wide range of b-lactam antibiotics which are regarded as first choice. In this report we described the case of A. europaeus infection in a young female patient admitted to Intensive Care Unit and the possible damage of vascular endothelium due to a chronic progressive actinomycosis that at first involved neck soft tissue, then cervical lymphnodes, and finally extended to the vascular structure.

A Curious Case of Actinomyces Naeslundii Bacteremia in a Patient with Metastatic Pancreatic Cancer.

Although considered a saprophyte, Actinomyces naeslundii can cause invasive infection leading to significant morbidity and mortality. Rarely encountered, bacteremia with this agent occurs in the setting of disrupted mucosal barriers. Previous studies suggest that actinomycosis may be a surrogate marker for poor prognosis in immunocompromised hosts. We report herein a case of a patient with metastatic pancreatic cancer who not only had a prompt resolution of Actinomyces bacteremia and a complete response to chemotherapy, but also remained disease free at 12 months after diagnosis. Our case may suggest that concomitant actinomycosis may not necessarily portend a poor prognosis in all immunocompromised patients.

Invasive actinomycosis: surrogate marker of a poor prognosis in immunocompromised patients.

OBJECTIVES: Actinomycosis is a rare disease favored by disruption of the mucosal barrier. In order to investigate the impact of immunosuppression on outcome we analyzed the most severe cases observed in patients hospitalized in three tertiary care centers. METHODS: We reviewed all cases of proven invasive actinomycosis occurring over a 12-year period (1997 to 2009) in three teaching hospitals in the Paris area. RESULTS: Thirty-three patients (16 male) were identified as having an invasive actinomycosis requiring hospitalization. The diagnosis was made by microbiological identification in 26 patients, pathological examination in eight patients, and by both methods in one. Twenty patients (61%) were immunocompromised. Actinomycosis localization was abdominal or pelvic in 17 patients, thoracic in 11, cervicofacial in three, and neurological in two. Twenty patients (61%) underwent surgery. All strains were susceptible to amoxicillin. All patients were treated with a beta-lactam antibiotic, for a median length of 82 days. Twenty-eight patients (85%) were considered as cured. Overall mortality at hospital discharge was 21% (7/33). Mortality was higher in immunocompromised patients (7/20; 21%) compared to non-immunocompromised patients (0/13) (p=0.027). However, six of seven deaths were directly related to the underlying disease. CONCLUSIONS: Actinomycosis is a cause of severe infection in immunocompromised patients and a surrogate marker of a poor prognosis in this specific population.

Laryngeal actinomycosis in an immunocompromised patient.

Actinomycosis of the larynx represents an unusual presentation for a common bacterium comprising the oral and oropharyngeal florae. There are few cases reported in the literature of laryngeal actinomycosis occurring primarily in the immunocompromised population. Here, we present a case in a 74-year-old man that occurred in the setting of neutropenia as a result of chemotherapy. Once the diagnosis was made with biopsy of the larynx, the infection was resolved after a prolonged course of penicillin-based therapy.

[A case of esophageal actinomycosis in a patient with normal immunity].

Actinomycosis is a chronic suppurative disease and caused by Actinomycosis species, principally Actinomyces israelii, which are part of the normal inhabitant on the mucous membrane of the oropharynx, gastrointestinal tract, and urogenital tract. It usually affects cervicofacial, thoracic and abdominal tissue. Cervicofacial type has the highest percentage of occurrence with 50%. Actinomycosis frequently occurs following dental extraction, jaw surgery, chronic infection or poor oral hygiene. It may also be considered as an opportunistic infection in immunocompromised patients such as malignancy, human immunodeficiency virus infection, diabetes mellitus, steroid usage or alcoholism. But, actinomycosis rarely occurs in adults with normal immunity and rare in the esophagus. We report an unusual case of esophageal actinomycosis which was developed in a patient with normal immunity and improved by therapy with intravenous penicillin G followed oral amoxicillin, and we also reviewed the associated literature.

Evidence supporting a protective role for th9 and th22 cytokines in human and experimental periapical lesions.

INTRODUCTION: The development of periapical granulomas is dependent on the host response and involves Th1, Th2, Th17, and Treg-related cytokines. The discovery of new Th9 and Th22 subsets, with important immunomodulatory roles mediated by interleukin (IL)-9 and IL-22, respectively, emphasizes the need for reevaluation of current cytokine paradigms in context of periapical lesions. We investigated the expression of IL-9 and IL-22 in active and stable human granulomas and throughout experimental lesion development in mice. METHODS: Periapical granulomas (N = 83) and control specimens (N = 24) were evaluated regarding the expression of IL-9 and IL-22 via real-time polymerase chain reaction. Experimental periapical lesions were induced in mice (pulp exposure and bacterial inoculation) and the lesions evolution correlation with IL-9 and IL-22 expression kinetics was evaluated. RESULTS: IL-9 and IL-22 mRNA expression was higher in periapical lesions than in control samples; higher levels of IL-9 and IL-22 were observed in inactive than in active lesions. In the experimental lesions model, increasing levels of IL-9 and IL-22 mRNA were detected in the lesions, and inverse correlations were found between IL-9 and IL-22 and the increase of lesion area in the different time point intervals. CONCLUSIONS: Our results suggest that Th9 and Th22 pathways may contribute to human and experimental periapical lesion stability.

Lipoproteins of Actinomyces viscosus induce inflammatory responses through TLR2 in human gingival epithelial cells and macrophages.

Actinomyces viscosus has been suggested to be associated with periodontal disease. However, the pathogenicity of this bacterium is not known. In this study, we examined inflammation-inducing activity by A. viscosus. Whole cells and a lipophilic fraction of A. viscosus ATCC19246 induced production of interleukin-8 and tumor necrosis factor alpha from both human oral epithelial cells and human monocytoid cells. This cytokine production was blocked by lipoprotein lipase treatment of the lipophilic fraction. In addition, anti-Toll-like receptor 2 antibody blocked the cytokine production. These results suggest that lipoprotein of A. viscosus triggers inflammatory responses in periodontitis by activation of Toll-like receptor 2.

[Actinomycosis in a 70 year old woman with a forgotten intrauterine contraceptive device]. / Geislagerlabólga í sjötugri konu med gleymda lykkju. Sjúkratilfelli og yfirlit um sjúkdóminn.

Actinomycosis is an infectious disease that has been known since the late nineteenth century. In the pre-antibiotic era it was thought to be rather common but with increased use of antimicrobial agents its incidence has decreased significantly. The causative agent, most commonly Actinomyces israelii, is part of the commensal bacterial flora. It can infect any tissue, respects no tissue boundaries and can spread throughout the body. The clinical presentation of this illness can be similar to malignant disease and definite diagnosis is sometimes not apparent until after surgery and histologic examination. We report the case of a 71 year old woman who suffered from actinomycosis of the uterus and ovaries due to a forgotten intrauterine contraceptive device that had been in place for over four decades. The disease presentation was consistent with malignant disease and tumor markers, CA 125, CA 19-9 and CEA, measured in blood were elevated. She was treated successfully with total hysterectomy and bilateral salphingo-oophorectomy, as well as penicillin for six months.

Host-derived pentapeptide affecting adhesion, proliferation, and local pH in biofilm communities composed of Streptococcus and Actinomyces species.

Salivary proline-rich proteins (PRPs) attach commensal Actinomyces and Streptococcus species to teeth. Here, gel filtration, mass spectrometry and Edman degradation were applied to show the release of a pentapeptide, RGRPQ, from PRP-1 upon proteolysis by Streptococcus gordonii. Moreover, synthetic RGRPQ and derivatives were used to investigate associated innate properties and responsible motifs. The RGRPQ peptide increased 2.5-fold the growth rate of S. gordonii via a Q-dependent sequence motif and selectively stimulated oral colonization of this organism in a rat model in vivo. In contrast, the growth of Streptococcus mutans, implicated in caries, was not affected. While the entire RGRPQ sequence was required to block sucrose-induced pH-decrease by S. gordonii and S. mutans, the N-terminal Arg residue mediated the pH increase (i.e., ammonia production) by S. gordonii alone (which exhibits Arg catabolism to ammonia). Strains of commensal viridans streptococci exhibited PRP degradation and Arg catabolism, whereas cariogenic species did not. The RGRPQ peptide mediated via a differential Q-dependent sequence motif, adhesion inhibition, and desorption of PRP-1-binding strains of A. naeslundii genospecies 2 (5 of 10 strains) but not of S. gordonii (n=5). The inhibitable A. naeslundii strains alone displayed the same binding profile as S. gordonii to hybrid peptides terminating in RGRPQ or GQSPQ, derived from the middle or C-terminal segments of PRP-1. The present findings indicate the presence of a host-bacterium interaction in which a host peptide released by bacterial proteolysis affects key properties in biofilm formation.

Lung, pleural and colon actinomycosis in an immunocompromised patient: a rare form of presentation.

Actinomycosis is caused by gram-positive filamentous organisms of the genus Actinomyces, which may spread through trauma. Most commonly, it is a cervicofacial disease due to dental infection or a thoracic disease secondary to aspiration of foreign bodies. Primary abdominal infection usually follows some form of mucosal disruption. Any organ of the human body may be involved so that a wide range of symptoms may be present. We report a rare form of actinomycosis involving the lung, pleura and colon concomitantly in an immunocompromised patient. A fine needle aspiration from a lung lesion detected the characteristic sulfur granules, and a pleural effusion culture confirmed the diagnosis. Clinical manifestations and treatment are discussed. Actinomycetes are rarely opportunistic agents in immunocompromised patients; thus the disease deserves special attention in those patients.

Actinomyces odontolyticus bacteremia.

We describe two immunosuppressed female patients with fever and Actinomyces odontolyticus bacteremia, a combination documented once previously in an immunocompetent male patient. The patients were treated with doxycycline and clindamycin; these drugs, with beta-lactams, are effective treatment for A. odontolyticus infections.