Atypical Form of Cervicofacial Actinomycosis Involving the Skull Base and Temporal Bone

Regular resident becomes aggressive enemy: Diagnosed on cytology

Actinomycosis, an oral cavity commensal, causes cervicofacial infection in patients associated with an immunosuppression state and local mucosal injuries. Bone involvement by this commensal is rare. In the present case, we report a case of left peri mandibular soft tissue, soft to firm, tender swelling in a 39-year-old immunocompetent male diagnosed as Actinomycosis infection on fine needle aspiration cytology (FNAC) and cell block preparation.

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.

Rhinocerebral Mucormycosis Associated With Anterior Skull Base Actinomyces Osteomyelitis in a Pediatric Patient With Type 1 Diabetes

Rhino-orbital-cerebral mucormycosis (ROCM) is a fulminant, often fatal, angioinvasive fungal infection commonly transmitted through inhalation of fungal spores and traumatic inoculation. While the literature has documented rare cases of infection in immunocompetent patients, the vast majority of case fatalities are noted in immunosuppressed populations. Common predisposing factors to infection include immunosuppressive therapies, hematologic malignancies, and most notably, uncontrolled diabetes. Actinomycosis is a subacute to chronic bacterial infection stemming from non-spore-forming anaerobic/microaerophilic bacteria of the genus Actinomyces. Infection with Actinomyces species has been documented across numerous anatomical sites; however, literature on concurrent infection with ROCM in pediatric patients is sparse. We document a case of a 17-year-old male with uncontrolled type 1 diabetes who presented to the emergency department with combined ROCM and actinomycotic infection of his anterior skull base.

Imaging of Acute and Chronic Skull Base Infection

Skull base infections are uncommon but can be life threatening without timely recognition. Imaging plays a crucial role because symptoms can be vague and nonlocalizing. Necrotizing otitis externa in diabetic or immunocompromised patients is the commonest cause of skull base osteomyelitis (SBO), followed by sinogenic infections and idiopathic central SBO. Multiparametric magnetic resonance (MR) and high-resolution CT are the mainstays for establishing a diagnosis and estimating disease extent, with MR being superior in ascertaining marrow and soft tissue involvement. Monitoring treatment response, of which imaging is a fundamental part, is challenging, with emerging promising imaging tools.

An Unusual Case of Early Dental Implant Failure in an Otherwise-Healthy Patient due to Actinomycosis

Actinomyces spp. are members of normal oral flora that may give rise to a rare disease- oral actinomycosis . Here we present a case of early implant failure associated with actinomycosis in an otherwise -healthy 43-year-old female and the treatment adopted following explantation. Clinically, one month after the implant placement, the peri-implant soft tissues were hyperplastic and associated with an excessive tissue reaction, bleeding, suppuration, deep probing depth , and implant mobility at #19 and #20 implants. Both implants were removed and all granulomatous tissues were thoroughly debrided. Histopathological examination revealed signs of acute ulcerative inflammatory reaction and Actinomyces colonies. The patient was prescribed short-term oral penicillins. After six months following explantation, the deficient bone was augmented with using a combination of absorbable collagen membrane, autogenous block and xenograft. The patient was followed up for one year ; and subsequently, two implants were reinserted at the same positions. The patient was followed up and no recurrences were observed. Implant failure due to actinomycosis is an extremely rare condition , and a definitive diagnosis is therefore essential for successful treatment.

Mastoiditis Masquerade

We report a case of primary temporal bone diffuse B-cell non-Hodgkin lymphoma, which is a rare entity. A 71-year-old male with a history of dementia and hemicraniectomy presented due to 1 month of a pronounced left ulcerative mastoid lesion. Strikingly, there were no cranial nerve deficits which was unexpected due to the degree of the lesion. Initially, infectious mastoiditis was suspected based on physical examination alone. Due to the patient being a poor historian, it was difficult to determine whether this was an acute or chronic issue. Temporal bone squamous cell carcinoma, infectious mastoiditis, and actinomycosis were on the differential, but biopsies revealed non-Hodgkin lymphoma.

Actinomyces as a Cause of Osteomyelitis of the Nasofrontal Suture in a Gelding

A 7-year-old American Quarter Horse gelding was referred to the JT Vaughan Large Animal Teaching Hospital at Auburn University, College of Veterinary Medicine, for an investigation of a recurrent swelling of the nasofrontal region. Computed tomography examination of the skull was most consistent with a sequestrum of the left nasofrontal suture with associated focal osteomyelitis and left conchofrontal sinusitis. Surgery to remove the sequestrum, debride the devitalized bone, and flush the left conchofrontal sinus was performed. A microbial culture was obtained at the time of surgery, which yielded a mixed heavy growth of an Actinomyces species. Quantitative PCR indicated a species with 93% resemblance to Actinomyces funkei. A treatment course of two weeks of oral chloramphenicol was prescribed. At three-month follow-up, the owner reported resolution of the swelling.