Periapical actinomycosis. An unusual case report

Periapical Actinomycosis: A Rare Subdivision of Cervicofacial Actinomycosis, Review of the Literature, and a Case Report

Background

Periapical actinomycosis, which is reckoned as a subgroup of cervicofacial actinomycosis, is an uncommon, more indolent, less invasive, and limited type of actinomycosis infection. However, it can be considerably underreported due to the low number of periapical surgical specimens that are submitted for histopathological analysis after excision of the lesion with the preliminary diagnosis of typical periapical infections. It is believed that during root canal treatment, the organisms are displaced from the oral cavity into the periapical regions as a result of failure to establish aseptic techniques which can further result in actinomycosis infections and, in rare instances, lead to more severe events and can even be life-threatening. Case Presentation. We intend to report a case of periapical actinomycosis in a 34-year-old female who presented with the chief complaint of pain and slight mobility of the mandibular right second premolar and first molar with no significant issues in the patient's medical history. Initial orthopantomography revealed a uniloculated, radiolucent lesion engulfing the apices of the aforementioned teeth. An incisional biopsy was then obtained which revealed fragments of fibroconnective tissue including few crushed bone particles severely infiltrated by acute inflammatory cells and some foamy macrophages. The suppurative exudate focally surrounds colonies of filamentous bacteria as round basophilic masses with radial configuration resembling “sulfur granules.” Surgical approach consisted of curettage accompanied with peripheral ostectomy and cautious burnishing of the two involved tooth roots.

Conclusion

This case report emphasizes the importance of aseptic techniques during endodontic and more invasive treatments, as they can cause penetration of Actinomyces into the periapical region which in some cases can lead to more serious complications and even life-threatening situations.

Prediction models for early diagnosis of actinomycotic osteomyelitis of the jaw using machine learning techniques: a preliminary study

BACKGROUND

This study aimed to develop and validate five machine learning models designed to predict actinomycotic osteomyelitis of the jaw. Furthermore, this study determined the relative importance of the predictive variables for actinomycotic osteomyelitis of the jaw, which are crucial for clinical decision-making.

METHODS

A total of 222 patients with osteomyelitis of the jaw were analyzed, and Actinomyces were identified in 70 cases (31.5%). Logistic regression, random forest, support vector machine, artificial neural network, and extreme gradient boosting machine learning methods were used to train the models. The models were subsequently validated using testing datasets. These models were compared with each other and also with single predictors, such as age, using area under the receiver operating characteristic (ROC) curve (AUC).

RESULTS

The AUC of the machine learning models ranged from 0.81 to 0.88. The performance of the machine learning models, such as random forest, support vector machine and extreme gradient boosting was significantly superior to that of single predictors. Presumed causes, antiresorptive agents, age, malignancy, hypertension, and rheumatoid arthritis were the six features that were identified as relevant predictors.

CONCLUSIONS

This prediction model would improve the overall patient care by enhancing prognosis counseling and informing treatment decisions for high-risk groups of actinomycotic osteomyelitis of the jaw.

Actinomycosis as a Rare Local Manifestation of Severe Periodontitis

Actinomycosis is a chronic suppurative infection primarily caused by anaerobic gram-positive filamentous bacteria, primarily of the genus Actinomyces. Oral-cervicofacial actinomycosis is the localization found most often, presenting as a soft tissue swelling, an abscess, a mass lesion, or sometimes an ulcerative lesion. Periodontitis-like lesions, however, are rare findings. This report describes the case of a 41-year-old healthy female patient (nonsmoker), who was referred to the clinic with dull and throbbing pain in the second quadrant. Tooth 25 showed increased mobility and probing pocket depths up to 10 mm, with profuse bleeding upon probing. Radiographically, considerable interproximal horizontal bone loss was found, and the diagnosis of periodontitis stage 3, grade C was made. The situation was initially stabilized with adhesive splinting and local anti-infective therapy. Two weeks later, the bone defect was treated with guided tissue regeneration (GTR) using a xenogenic filler material (BioOss Collagen) and a resorbable membrane (Bio-Gide). Due to a suspicious appearance of the excised granulation tissue, the collected fragments were sent for histopathological evaluation. This evaluation revealed a chronic granulomatous inflammation with the presence of filamentous bacterial colonies, consistent with Actinomyces. The patient was successfully treated. While there are only few reports in the literature, actinomycotic lesions represent a rare but possible finding in cases with localized periodontal destruction. In conclusion, systematic biopsy of the infrabony tissue in localized periodontal lesions may help to provide a more accurate counting of Actinomyces-associated lesions, thereby improving diagnosis, therapy, and prevention.

Actinomycosis is not Frequent in the Periapex But is a Persistent Lesion

Periapical actinomycosis caused by a gram-positive anaerobic pathogen characterizes a typical extra-radicular infection. This study determined the frequency and correlated the content of bacteria colonies with the of periapical actinomycosis size. The study comprised a total of 218 periapical lesions (PL) (cysts, granulomas or abscess). The specimens embedded in paraffin were sliced into 4-µm sections and stained with hematoxylin-eosin, Gram, Periodic Acid-Schiff (PAS) and Grocott's stain. The presence of bacterial colonies composed of filamentous structures labeled with the histochemical stains were described as Actinomyces, and for each case, the bacterial colonies were counted and measured. The correlation between the number and size of bacterial colonies and the size of PL was tested using Pearson's adjusted correlation coefficient. From 218 PL, bacterial colonies were identified in 64 biopsies. Seven cases (0.3%) fulfill the criteria for diagnosis of periapical actinomycosis. All of cases were therapy-resistant and did not showed periapical repair after 12 months of follow-up. Periapical surgery or dental extraction was performed. The correlation test indicated no correlation between the number of bacterial colonies and the lesion size (p=0.752, r=-0.148). However, a larger bacterial colony size generally resulted in a larger periapical lesion (P=0.000, r=0.657). The frequency of periapical actinomycosis was low, and this lesion should be included in the differential diagnosis of PL. The size of the Actinomyces colonies seemed to contribute to increase the size of the periapical lesion.

Actinomycosis osteomyelitis of the jaws: Report of four cases and a review of the literature

Actinomycosis osteomyelitis of the jaw bones, particularly in the maxilla, is an extremely rare disease. This report presents two cases of maxillary and two cases of mandibular actinomycosis osteomyelitis, with the diagnosis particularly based on histological procedures. The highly diversified pathogenicity of the phenomenon and the absence of solid diagnostic criteria are discussed. Laboratory challenges are emphasized, and a comprehensive overview of the entity including treatment alternatives is given along with a review of the relevant literature.

Periapical actinomycosis

Actinomycosis is a rare chronic infection caused by species of Actinomyces and characterised by abscess formation, tissue fibrosis, suppurative lesions and fistulas with purulent discharge containing sulphur granules. Owing to its multiform manners of presentation and non-specificity from its clinical features, it has been considered as a challenging diagnosis. Periapical actinomycosis is one of the rarest forms of actinomycosis occurring in the maxillofacial region. In its occurrence it presents in the form of persistent and recurrent draining fistula in the periapical region. We report a case of periapical actinomycosis occurred in endodontically treated teeth and accidentally found to be actinomycosis during histopatological examination. An insight towards the portal of entry of the organisms into the periapical region is also discussed. The practice of sending even a tiny bit of tissues to histopathology obtained from periapical surgery will very well demonstrate this disease and help in rapid resolution through appropriate antibiotic therapy.

On the causes of persistent apical periodontitis: a review

Apical periodontitis is a chronic inflammatory disorder of periradicular tissues caused by aetiological agents of endodontic origin. Persistent apical periodontitis occurs when root canal treatment of apical periodontitis has not adequately eliminated intraradicular infection. Problems that lead to persistent apical periodontitis include: inadequate aseptic control, poor access cavity design, missed canals, inadequate instrumentation, debridement and leaking temporary or permanent restorations. Even when the most stringent procedures are followed, apical periodontitis may still persist as asymptomatic radiolucencies, because of the complexity of the root canal system formed by the main and accessory canals, their ramifications and anastomoses where residual infection can persist. Further, there are extraradicular factors -- located within the inflamed periapical tissue -- that can interfere with post-treatment healing of apical periodontitis. The causes of apical periodontitis persisting after root canal treatment have not been well characterized. During the 1990s, a series of investigations have shown that there are six biological factors that lead to asymptomatic radiolucencies persisting after root canal treatment. These are: (i) intraradicular infection persisting in the complex apical root canal system; (ii) extraradicular infection, generally in the form of periapical actinomycosis; (iii) extruded root canal filling or other exogenous materials that cause a foreign body reaction; (iv) accumulation of endogenous cholesterol crystals that irritate periapical tissues; (v) true cystic lesions, and (vi) scar tissue healing of the lesion. This article provides a comprehensive overview of the causative factors of non-resolving periapical lesions that are seen as asymptomatic radiolucencies post-treatment.

Direct detection of Actinomyces spp. from infected root canals in a Chinese population: a study using PCR-based, oligonucleotide-DNA hybridization technique

OBJECTIVES

The poor sensitivity of phenotypic identification techniques has hampered the taxonomic differentiation of Actinomyces. Hence we developed a sensitive and specific, PCR-based oligonucleotide-DNA hybridization technique to detect Actinomyces spp. and, used this method to detect these organisms in samples directly obtained from infected root canals.

METHODS

A total of 32 samples from 28 Chinese patients, with primary root canal infections, aseptically exposed at the first patient visit, were studied. Whole bacterial genomic DNA was isolated directly from paper point samples. The variable regions of 16S ribosomal DNA of bacteria were amplified and labeled with digoxigenin for further hybridization and detection. A total of seven oligonucleotide probes specific for A. bovis, A. gerencseriae, A. israelii, A. meyeri, catalase-negative A. naeslundii (genospecies 1 and 2), catalase-positive A. naeslundii genospecies 2 and A. odontolyticus were used.

RESULTS

16 of the 32 teeth were infected with one or more Actinomyces species. The prevalence rates of the examined species were: A. odontolyticus 31.3%, A. meyeri 9.4%, A. naeslundii 9.4%, A. israelii 6.3% and A. gerencseriae 3.1%; no A. bovis was detected in any of the canals. Furthermore, A. odontolyticus was isolated more frequently from root canals with caries or a history of caries (Fisher's exact test: P=0.0496; Odds ratio=9.00, 95% confidence interval: 0.97-83.63), and A. naeslundii was significantly associated with traumatized teeth (Fisher's exact test: P=0.0121; Odds ratio=57.00, 95% confidence interval: 2.10-1546.90). However, no significant correlation was found between Actinomyces spp. and clinical symptoms and signs, such as pain, swelling, percussion to tenderness, sinus and periapical radiolucency.

CONCLUSION

Actinomyces spp. may be important pathogens of root canal infections. A. naeslundii in particular may be related with traumatized teeth. A. odontolyticus appears to be involved in infections related to caries, exposure of dentinal tubules during cavity preparation and/or leaking restoration, but further clarification with large samples is necessary.

Case report of regional alveolar bone actinomycosis: a juvenile periodontitis-like lesion

BACKGROUND

Cervicofacial actinomycosis infection most often involves the mandibular bone and rarely the alveolar crest.

METHODS

We describe a 14-year-old patient who had actinomycosis involving the alveolar bone at the left lower dental quadrant region. Resembling juvenile periodontitis, it was difficult to diagnose properly and resulted in devastating dental and periodontal consequences: loss of one tooth with most of its adjacent regional alveolar bone, severely compromising the support of two other teeth.

RESULTS

With the diagnosis came successful treatment, including surgical removal of the soft and hard tissues with concomitant prolonged penicillin administration.

CONCLUSIONS

We feel that this case should raise the interest and concern of both the periodontist and the general practitioner so that early diagnosis can be obtained, significantly improving the clinical outcome.

Comparison of clinical and histologic diagnoses in periapical lesions

OBJECTIVE

To determine the frequency with which histopathologic examination of periapical biopsy specimens contributed information not anticipated clinically.

STUDY DESIGN

Clinical and histopathologic information from 805 sequentially submitted periapical biopsy specimens over a 2-year period was compared. Clinical data included endodontic status, age and sex of patient, location of lesion, and submitting clinician. Histopathologic diagnoses were categorized as 1) sequelae of pulpal necrosis (SPN), 2) complicated SPN (CSPN) with infection or antral involvement, or 3) periapical lesions unrelated to pulpal necrosis (PLUPN).

RESULTS

Of the 805 cases, 788 (97.9%) were SPN, 9 (1.1%) were CSPN, and 8 (1%) were PLUPN, representing a range of locally aggressive but benign lesions and 1 malignancy. Comparison of clinical and histologic diagnoses indicated that the clinical interpretation was inaccurate in 4.1% of cases (suggesting SPN in PLUPN cases or PLUPN in SPN cases). In another 0.9% of cases, the histologic analysis (indicating CSPN) contributed additional information to the clinical diagnosis.

CONCLUSIONS

A histopathologic examination contributed clinically relevant information in 5.0% of submitted cases. General extrapolation of this figure is not possible. Theoretical considerations, which could positively or negatively bias this figure, are discussed.

Experimental chronic infection induced in mice by Actinomyces israelii entrapped in alginate gel

Tissue responses to experimentally induced actinomycotic lesions were investigated in mice by both light and transmission electron microscopy. Micro-organisms of Actinomyces israelii were entrapped in alginate gel and injected into the subcutaneous tissue over the periosteum of the mouse cranium. One day after the injection (initial stage), a non-stained amorphous structure was located in the core of the lesion, corresponding to the injected gel with bacteria. Numerous neutrophils surrounded the core region and phagocytized the injected complex actively. At days 3-7 (intermediate stage), the lesion became well developed. The core structure became eosinophilic and separated to form island-like structures. No lesion was recognized in the control group (gel without bacteria) until day 14. After 30 days (late stage), the lesions displayed more static features, similar to the "sulphur granules" characteristic of actinomycotic lesions. At the late stage, foamy cells increased in number and took the place of neutrophils in the alginate islands. By transmission electron microscopy these foamy cells were seen to be filled with lysosomal vesicles containing electron-dense foreign material. Thus, these cells appeared to be macrophages that had phagocytized degenerated neutrophils containing bacteria. Along with the active phagocytosis by foamy cells that progressed in the late stage, a collagenous capsule became conspicuous and separated the lesion from the intact tissue. The bacteria remained in the gel islands until at least day 60, although they considerably decreased in number with time. Serum IgG antibody titres began to rise within 24 h of the injection, reached a peak concentration at day 14 and remained a significantly high (p < 0.01, vs 0 time) until day 120. These results suggest that this animal model is useful for inducing experimental chronic infectious lesions.

Cervicofacial actinomycosis: a diagnostic challenge

Actinomycosis was first described as a clinical entity over 100 years ago. However, the fundamental characteristics of this entity have not been fully discussed, and major questions remain unanswered, such as the highly diversified pathogenicity of the phenomenon according to numerous published case reports and clarification of solid diagnostic criteria. Even the frequency of cervicofacial actinomycosis occurrence is unclear; some authors consider it to be rare and others to be common. We present 11 cases examined and treated in our department within the last 14 years along with a review of the literature. Diagnostic problems are emphasized, and a comprehensive overview of the entity is suggested.

Susceptibility of Actinomyces israelii to antibiotics, sodium hypochlorite and calcium hydroxide

Actinomyces israelii has been repeatedly implicated as a cause of failure of endodontic therapy. This study investigated the antimicrobial effect of antibiotics as well as intracanal medicaments, sodium hypochlorite solution and calcium hydroxide, on this important pathogen. Growth of A. israelii was inhibited by low concentrations of antibiotics, yet high concentrations were not bactericidal for A. israelii over 1 week. When A. israelii was exposed for 2-6 weeks at concentrations equivalent to clinical serum levels, the antibiotics were lethal. The results reveal a species-specific antibiotic tolerance for A. israelii. Both sodium hypochlorite solution and calcium hydroxide were found to be highly effective in killing A. israelii.

Periapical actinomycosis: report of a case and review of the literature

This case of periapical actinomycosis presented the clinical picture of chronic periapical inflammation. The diagnosis was based on the histological examination of the periapical lesions suggesting the necessity for routine histological examination. Although root canals provide a primary port of entry the Actinomyces organisms into the periapical tissue, periapical actinomycosis, is considered extremely rare. This may be due to the omission of routine histological examination of periapical lesions and the clinical behavior of the disease. The large number of cases reported during the last decade indicates that periapical actinomycosis is more frequent than what it is believed and this is important in the daily dental practice.

Actinomycosis associated with a root-treated tooth: report of a case

An unusual case of a persistent infection related to a root-filled tooth is reported. Microscopical evaluation revealed the cause to be a large mass of Actinomyces-like filaments, and microbiological culture yielded a low level of Actinomyces israelii. The significance of such a presentation is discussed.

Periapical actinomycosis. Report of a case and review of the literature

An analysis of actinomycosis in periapical inflammatory lesions in the English-language literature was carried out. Nineteen cases were found, and an additional case is presented. The most frequent locations for these infections were the maxillary central incisor region and the mandibular first molar region. The average age of the patients was 27.5 years, and a slight male predilection was noted. Formation of draining sinuses, local swelling, and pain were the most common presenting symptoms. Many of the cases were diagnosed following endodontic procedures, suggesting that such procedures might be responsible for introducing the organisms into the periapical tissues or that the organisms might be responsible for some cases of endodontic failure.

Actinomycosis after cyst enucleation

A case report of actinomycosis associated with bony sequestra resulting from a post-operative infection of a dental cyst in a young patient is presented. The need for careful wound debridement as a prophylactic measure is emphasized.

Actinomyces of infected dental root canals

The aim of the present study was to identity Actinomyces occurring in infected dental root canals. Out of twenty-five isolated Actinomyces strains, four were A. israelii, four were A. naeslundii, four were A. odontolyticus, and six were A. viscosus. Seven strains could be identified only as Actinomyces spp. The relative frequency of various species of Actinomyces isolated from root canals was similar to that of carious dentin. The Actinomyces strains were usually part of polymicrobial infections. These infections could usually be eliminated by one or two conventional endodontic treatments. In two cases, however, A. israelii was repeatedly isolated in pure culture from the root canals. These two infections had to be eliminated by means of periapical surgery.

Conservative treatment of periapical actinomycosis

A patient with periapical actinomycosis of approximately 3 years' duration was treated conservatively with tissue management and antibiotic therapy. Twelve months after therapy, bone regeneration is almost complete and there is no sign of recurrence.