Case Report - (2020) Volume 10, Issue 11
Actinomycosis is a rare bacterial infection caused by Actinomyces species, gram-positive, microaerophilic bacteria, which, under normal circumstances, colonize oral flora within gingival cervices and tonsillar crypts, gastrointestinal tract and genital microbiota. Firstly in humans, A. israelii was isolated and described in 1878 by James Israel. So far, more than 30 species of Actinomyces have been identified in humans, out of which most frequently isolated species in infections is Actinomyces israelii.
Actinomycosis • Bacteria • Microscopy
The name Actinomycosis means “ray fungus” for its typical filamentous, fungal-like appearance in infected tissues. In spite of their name Actinomyces are true bacteria and they cannot form spores as fungi. Their filaments, which fragment into bacillary forms, are much narrower than fungal hyphae [1-3]. It is a typical strain of Actinomyces that causes chronic granulomatous inflammation, e.g. an abscess formation, draining sinus tracts, fistulae and tissue fibrosis, which characteristically contain sulfur granules with typical yellow color. The granules are named due to their appearance. The granule is composed of an internal tangle of mycelial fragments and a rosette of peripheral and can be seen without a need of microscopy . They are stabilized by a protein-polysaccharide complex and mineralized by host calcium phosphate. This complex possibly provides a resistance to host phagocytic cells . Actinomycosis is an extremely rare diagnosis in pediatric population-it makes up for about 3% of total cases caused by actinomyces . The most frequently infected tissues in order are head and neck (50-60%), chest (15-20%) and abdomen (about 20%) . It is well recognized that for the infection to develop, the integrity of mucosa must be disturbed. The further spread of actinomycosis is atypical as it invades surrounding structures ignoring anatomical barriers [6,7]. A final diagnosis might prove difficult. Imagining methods as USG, CT scan or MR might be used, but radiology most frequently describes only the mass which expands into the adjacent soft tissues .
The standard diagnostic procedure involves the collection of biological material for bacterial cultivation, microscopic examination and specific microbiological tests by needle aspiration of an abscess, fistula or the sinus tract or by biopsy samples . As actinomycetes are microaerophilic microorganisms, either a swift transportation of samples to the laboratory or an anaerobic transport medium must be secured. During the isolation, these microbes require an enriched medium and incubation at 37°C with 6 to 10% carbon dioxide. Because of their slow growth, for adequate detection, cultures should be observed for at least 14 to 21 days . Microscopic examination reveals a typical finding of an outer zone of granulation and a central zone of necrosis. In the central there are typically multiple basophilic granules presented micro-colonies of Actinomyces . Actinomycetes are usually sensitive to beta-lactam antibiotics, particularly Penicillin G or amoxicillin. Complete eradication of actinomycetes is achieved by long-term antibiotic treatment. Therefore, it is recommended that during the first four to six weeks, large doses of antibiotics should be intravenously applied, followed by oral antibiotics. Optimal treatment should last 6 months, the minimum being 2 months. In severe cases, therapy can be continued for up to 12 months. Ceftriaxone or amoxicillin can be used as alternatives to penicillin G. Surgical interventions are often required for a definitive diagnosis and extensive operations should be considered in complicated cases . Here we present a unigue clinical case of actinomycotic abscess of the thyroid gland in a 3-yearsold child.
Most cases of cervicofacial actinomycosis are found in the perimandibular region, but localities of primary infection such as the tongue, sinus cavities, middle ear, larynx and the thyroid gland have also been described, too [12-14]. The localization of abscesses in the thyroid gland is unique since it is highly resistant to bacterial infection due to rich venous and lymphatic supply, high iodine content and a protective fibrotic capsule on the surface . There are certain predisposing factors which can lead to actinomycosis, such as poor oral hygiene (tooth decay, gingivitis, tooth infection), trauma of oral mucosis (dental extraction, damaged tissue after radiation or cervicofacial surgery, maxillofacial trauma, infection caused by the growth of secondary teeth)  or immunocompromised patients suffering from diabetes mellitus, immunosuppression, bisphosphonate related osteonecrosis or malnutrition . In childhood age, the pathogenesis of actinomycosis of the thyroid gland could be boosted by a persistent thyroglossal duct or piriform sinus, which facilitates communication between the oral cavity and the thyroid gland parenchyma . Our patient was diagnosed with underlying thyroglossal duct may have allowed for the infection to spread. We managed to disturb its development and close anatomical communication. As a result, we prevented further reinfection. Cervicofacial actinomycosis can present with a variety of clinical signs and specific symptoms depending on the localization of infectiontypically, these are a slow-growing indurated mass (weeks to months), superficial tension around the mass, less common pain (resulting from the compression of adjacent structures), dyspnea, dysphagia and local signs of inflammation in the infected region. Fistulation with the expression of a thick yellow exudate with characteristic sulfur granules is rare, but is the most easily recognized manifestation. Also, fever (>50% of patients) and fatigue can be observed in patients. Lymphadenopathy is uncommon, because of its atypical spread in the human organism .
Symptoms can mimic a number of diseases, particularly malignancy and a thyroid gland infection of other agents. Thyroid nodules are less common in children than in adults, but have a greater risk of malignancy. It is of upmost importance to distinguish between benign lesions, such as a nodular hyperplasia, intrathyroidal thymus and cysts. Benign lesions are mostly diagnosed accidentally and patients are asymptomatic. As for malignant lesions of the thyroid gland, the most common type in children is papillary thyroid carcinoma . The acute suppurative infection of thyroid gland can cause S. aureus, S. pyogenes, S. pneumoniae, Klebsiella species, H. influenza, Bacteroides and other pathogens [20,21]. Predisposing factors such as fistula sinus pyriform (up to 70% of children), congenital brachial fistula and thyroglossal duct have been described [22,23]. Acute thyroiditis typically presents with a sudden onset of symptoms as a fever, a unilateral neck pain, a sore throat, dysphagia and dysphonia. Visually, it is felt as thyroid mass with tenderness, erythema of the adjacent skin and regional lymphadenopathy. Laboratory findings show leukocytosis and a high level of CRP; thyroid hormones are usually normal, however, in some cases may develop hyperthyroidism may develop through the release of the thyroid hormone into circulation due to damaged thyroid follicular cells . Sonography reveals unilobular swelling and/or abscess formation  (Figures 1-4).
Traditionally, root canal morphology of upper 1st molar has three roots of 4 root canals . It is distributed as the following, MB1, MB2, DB and P . As the operator experience has a significant role in the identification and management of complex root canals . Other factors, such as Dental Operating Microscope (DOM) [19,20], ultrasonic tip instrument  and 3-dimensional radiograph (cone-beam computed tomography)  have ultimate benefit in such cases. In the first appointment, we explore four root canals. In the second appointment, we can locate two more root canals. The total root canals shaped and cleaned is six in the third appointment at just before obturation we discovered the DP root canals, the seventh one. Unfortunately, in our center, at the time of case management, no DOM, or ultrasonic or CBCT. The dental loupe of 2.5X power is very helpful in the exploration of canal orifices. In a clinical study, 312 cases of root canal treatment on the first and second maxillary molars. The endodontists, who used the microscope, identified 57% of the MB2 versus 55% who used dental loupes . This result shows the importance of any magnification power in the location and management of the root canal system. In this case, counting numbers of root canals come with the problem as MB1 and MB2 and DB1 and DB2 are joint shortly to form single canal about 3-4 mm from pulpal floor. According to Stropko description in his meticulous work, these canals count as a separate root canal . In our case, Post-treatment CBCT shows some difficulty in clarity of the pulpal floor and coronal anatomy of the tooth, due to beam hardening phenomena, that result in image distortion [23,24]. The traditional radiograph of two-dimensional view of limited help in such case. We relay in to determine the working length on apex locator. In published case reports, there is a limited number of upper 1st molar with more than five root canals .
In conclusion, cervicofacial actinomycosis is known as the “great masquerader” of head and neck disease; authors have claimed that fewer than 10% of infections are correctly diagnosed. The differential diagnosis remains difficult because of non-specific manifestations, non-clear radiological findings and hard microbiological identification. When you confirm actinomycotic infection in your patient, it is important to take predisposing factors into consideration in order to prevent reinfections.