Bronchiectatic Actinomycosis with Osseous Metaplasia Masquerading as Lung Cancer.

After the publication of the original article, the authors noticed an error in the departmental affiliation of one of the contributors, Don MASCARENHAS. The corrected version of the department is provided below, and the original article has been updated accordingly. Archana BHAT < sup > 1 < /sup > , Manjunath J < sup > 1 < /sup > , Don MASCARENHAS < sup > 2 < /sup > < br / > Department of < sup > 1 < /sup > Pathology and < sup > 2 < /sup > Pulmonology, Father Muller Medical College, MANGALORE, INDIA.

Skin and Soft Tissue Actinomycosis in Children and Adolescents.

BACKGROUND: Pediatric actinomycosis studies are limited to case reports or small case series. In this retrospective cohort study, we aimed to describe characteristics of skin and soft tissue actinomycosis in adolescents and children. METHODS: We conducted the study from January 2019 to December 2022, including patients ≤21 years of age with at least 1-year follow-up data. All clinical cultures obtained under sterile conditions with Actinomyces growth were included. RESULTS: One hundred four patients met inclusion criteria; median age 19 (interquartile range: 17-20) years, 68.3% female, 46.2% Black and 47.1% Hispanic. The median antibiotic treatment duration was 10 (7-10) days, and majority of patients received treatment with non-first-line Actinomyces antibiotics. Infectious disease consultation was requested for only 7 patients during their initial skin and soft tissue actinomycosis treatment. One-third of the patients with skin and soft tissue actinomycosis had documented recurrence within a median of 10 (interquartile range: 6-16) months of the initial episode. Monobacterial culture growth (85.7% vs. 63.8%, P = 0.02), patients with body mass index >25 (75% vs. 52.6%, P = 0.04) and patients with prior abscess in the same area (18.8% vs. 51.4%, P = 0.001) were significantly higher in patients with recurrent actinomycosis compared to the nonrecurrent group. In a univariate logistic regression model, they were found to be significantly associated with recurrence; monobacterial growth [odds ratio (OR): 3.4; 95% confidence interval (CI): 1.2-9.9], body mass index >25 (OR: 2.7; 95% CI, 1.1-7.0) and prior abscess (OR: 4.6; 95% CI: 1.9-11.2). CONCLUSIONS: Our study results highlight the importance of considering Actinomyces species in skin and soft tissue infections, especially in recurrent ones, and risk factors for recurrence. Suboptimal antibiotic utilization, very low numbers of consultations with infectious diseases and high recurrence rate suggest that providers should be informed and updated regarding this rare but hard-to-treat infection.

A rare case report of liver masses caused by Actinomyces species.

Actinomycosis is a rare infection caused by Actinomyces spp. Of all actinomycosis infections, only 5% of Hepatic Actinomycosis (HA) infection has been reported. This disease is often misdiagnosed as a malignancy. This case report presents a 45-year-old woman with diabetes, initially suspected of intrahepatic cholangiocarcinoma, but after careful tissue staining, we found the results supported HA infection.

Actinomyces-induced Osteomyelitis of the Mandible - A Rare Disease?

BACKGROUND: Actinomyces species are commensal oral cavity flora that can cause jaw osteomyelitis. Osteomyelitis of the jaw by Actinomyces is rare, and its presentation can be confused with many different pathologies. CASE PRESENTATION: This is the case of a 61-year-old female with breast cancer and on chemotherapy as well as non-invasive carcinoma of the tongue who initially presented to the dentist with white spots in the right mandible near the incisors associated with right mandible pain and swelling. Actinomyces-induced osteomyelitis of the mandible was diagnosed. The patient was treated with penicillin V for 6 weeks along with a course of hyperbaric oxygen therapy, which resulted in the complete resolution of the infection. CONCLUSION: In summary, jaw osteomyelitis caused by Actinomyces should always be part of the differential diagnosis; as these organisms are commensal flora. The symptoms manifested are non-specific, and such a diagnosis could be easily missed, resulting in delay of care and disease progression.

[Skin abscess caused by Actinomyces radingae]. / Hautabszess verursacht durch Actinomyces radingae.

We report a 77-year-old man with a skin abscess caused by Actinomyces radingae. Targeted antibiotic therapy with amoxicillin/clavulanic acid for 6 weeks resulted in clearing of the infection. A. radingae is a rare pathogenic agent of skin and soft tissue infections. As with other Actinomyces infections, the early identification of the pathogen and specific antibiotic therapy is crucial for successful resolution of the infection because of the chronic course and the long treatment time needed. Usually, A. radingae is sensitive to ß­lactam antibiotics.

Actinomycotic Sinomaxillary Infection in a COVID-19 Patient: A Case Report and Review of the Literature.

Individuals with COVID-19 are prone to a variety of infections due to immune dysregulation. The present report presents a case of actinomycotic infection in the maxillary bone and sinus region in a patient with a history of COVID-19. This case report highlights the importance of considering bacterial infections including actinomycosis when encountering destructive lesions resembling more prevalent fungal infections due to different therapeutic medication protocols. In addition, a literature review of the existing reports of similar post-COVID-19 actinomycotic infection is presented.

Cryptococcal meningoencephalitis with Actinomyces odontolyticus sepsis: a case report and literature review.

BACKGROUND: The combined infection of actinomyces odontolyticus sepsis and cryptococcal encephalitis is rare in routine clinical practice. Thus, we presented this case report and literature review to provide clues to improve such patients' diagnoses and treatment processes. CASE PRESENTATION: The main clinical manifestations of the patient were high fever and intracranial hypertension. Then, we completed the routine cerebrospinal fluid examination, biochemical detection, cytological examination, bacterial culture, and India ink staining. Firstly, the blood culture suggested actinomyces odontolyticus infection, considering the possibility of actinomyces odontolyticus sepsis and intracranial actinomyces odontolyticus infection. Accordingly, the patient was administered penicillin for treatment. Although the fever was slightly relieved, the symptoms of intracranial hypertension did not relieve. After 7 days, the characteristics of brain magnetic resonance imaging and the results of pathogenic metagenomics sequencing and cryptococcal capsular polysaccharide antigen suggested that cryptococcal infection. Based on the above results, the patient was diagnosed with a combined infection of cryptococcal meningoencephalitis and actinomyces odontolyticus sepsis. Anti-infection therapy with 'penicillin, amphotericin, and fluconazole' was provided, improving the clinical manifestations and objective indexes. CONCLUSION: The combined infection of Actinomyces odontolyticus sepsis and cryptococcal encephalitis is first reported in this case report, and combined antibiotics with 'penicillin, amphotericin, and fluconazole' are effective.

Actinomyces: An Under Appreciated Cause of Postoperative Infection in Rhinoplasty.

OBJECTIVE: To discuss a case series of Actinomyces infection post-rhinoplasty and review the literature for correct diagnosis and management. STUDY DESIGN: Case series with chart review. METHODS: Three cases are presented of patients with a history of recurrent infectious symptoms post revision rhinoplasty later being diagnosed as Actinomyces. RESULTS: Three patients were identified having undergone revision rhinoplasty and later being diagnosed with Actinomyces infection. They initially presented with underwhelming physical exams, mild erythema, slight swelling, yet extreme pain. They also had periods of recurrent infection once antibiotics were stopped. Aerobic, anaerobic, fungal, and Actinomyces cultures were sent to pathology and returned positive for Actinomyces. Treatment typically involved a combination of prolonged antibiotics, incision and drainage, and/or surgical debridement. CONCLUSIONS: Awareness of Actinomyces as a possible cause of infection post-rhinoplasty is significant as this pathogen can lead to extensive tissue destruction and fistula formation which could be detrimental for a rhinoplasty. Duration of treatment is beyond typical lengths for other infections and a specific culture for Actinomyces is required to be sent as it isn't captured in standard aerobic/anaerobic cultures. Therefore, a high index of suspicion is required by physicians to ensure that patients are evaluated thoroughly. Laryngoscope, 133:2948-2950, 2023.

Primary Hepatic Actinomycosis Mimicking Neuroendocrine Tumor.

INTRODUCTION: The Actinomyces species is a fastidious, gram-positive, non-spore-forming bacteria that thrive in microareophilic and anaerobic conditions. Infection in the liver, an organ rarely affected by this pathogen, is presumed to be caused by hematogenous spread through the portal vein from a mucosal injury or other abdominal injury or a focus of infection. CASE DESCRIPTION:  A 60-year-old male patient has a mass lesion of 15 × 10 cm in the left lobe on computed tomography. A tru-cut biopsy was performed with USG, and fragmented tissue pieces were obtained. In histopathological examination, these samples were reported as tumors with neuroendocrine differentiation. The biopsy sample contains a large amount of tumor neighborhood, and tumoral area is quite small. And, therefore, a clear diagnosis could not be found. A mass lesion with mildly increased Ga 68 DOTATATE uptake was observed in the left lobe of the liver (SUVmax value 3.8) and was interpreted in favor of the primary neuroendocrine tumor of the liver. DISCUSSION: Actinomyces cases are very rare and their diagnosis is usually delayed due to its slow and insidious course, and lack of specific clinical and radiological findings. It is difficult to make a correct diagnosis even in microbiological examinations and biopsy materials obtained in the presence of imaging methods. It can mimic tumors of abdominopelvic structures. CONCLUSION: Actinomyces should be kept in mind in cases with liver masses accompanied by previous abdominal surgery, abdominal trauma, high fever, and leukocytosis.

A case of recurrent acute cholecystitis caused by Actinomyces odontolyticus, rare actinomycosis.

BACKGROUNDS: Actinomyces species are gram-positive, obligate anaerobic rods and are rare causes of cholecystitis. Because Actinomyces species are anaerobic bacteria, it is difficult for Actinomyces to survive in bile apart from A. naeslundii. We experienced a case of recurrent acute cholecystitis caused by A. odontolyticus. CASE PRESENTATION: A patient had been diagnosed with acute cholecystitis and treated one month before and after that, admitted to our hospital because of recurrent cholecystitis. Gram stain of the bile revealed gram-positive rods and gram-positive cocci. We found A. odontolyticus and MRSA in bile culture and MRSA in blood culture. We administered piperacillin-tazobactam and then changed it to ampicillin-sulbactam and vancomycin. The patient underwent laparoscopic cholecystectomy and was discharged safely. CONCLUSIONS: To our knowledge, this is the first case of cholecystitis caused by A. odontolyticus. Cholecystitis caused by Actinomyces species is rare. In addition, we may overlook it with the low positivity of bile cultures of Actinomyces. Whenever the cholecystitis recurs without any obstruction of the biliary tract, we should search for the gram-positive rods hidden in the bile, such as A. odontolyticus, as the causative organism, even if the bile culture is negative.

Disseminated cutaneous Actinomyces bovis infection in an immunocompromised host: case report and review of the literature.

BACKGROUND: Actinomycosis is an uncommon endogenous bacterial infection caused by Actinomyces species, characterized by the development of abscesses, tissue fibrosis, and fistulisation. It remains a diagnostic challenge, due to its similarities with diverse aetiologies' presentation, such as neoplasms, tuberculosis, or fungal infections. Actinomyces bovis is a microorganism rarely reported as a cause of human disease. Cutaneous involvement is sporadic. In this case, Actinomyces bovis was responsible for disseminated cutaneous disease in an immunosuppressed patient. CASE PRESENTATION: We report the case of a 69-year-old female with multiple skin masses, under immunosuppressive therapy due to ulcerative colitis. Imaging exams were compatible with multiple cutaneous abscesses in the cervicofacial region and limbs. Actinomyces bovis was isolated in culture after abscess drainage. Antimicrobial therapy with parenteral penicillin G and oral amoxicillin was administered for 6 months, with complete resolution of cutaneous lesions and no relapse of the infection. CONCLUSIONS: Considering actinomycosis as a possible diagnosis in the presence of subacute/chronic recurrent mass-like cutaneous lesions, especially in the setting of immunosuppression, may reduce the burden associated with delayed diagnosis and incorrect treatment and provide better outcomes and improvement of patient's quality of life.

Cutaneous Actinomycosis of the Perineum in an Immunocompetent Man.

ABSTRACT: We present a case of primary cutaneous actinomycosis of unclear pathogenesis. A 30-year-old-man with no significant medical or surgical history presented to the emergency department with a 2-week history of a tender perineal mass. The patient denied trauma or perforating injury to the area. Examination of the area revealed an indurated, nonfluctuant, erythematous papulonodule located 2 cm from the anus. The lesion was unresponsive to oral and topical antibiotics and was therefore excised. The excision specimen revealed a dense mixed infiltrate partially filling the reticular dermis and extending into the subcutaneous fat. The infiltrate surrounded grains of basophilic material with an outer rim of eosinophilic radiating Splendore-Hoeppli material. Within the grains, filamentous bacteria were highlighted with Periodic acid-Schiff and Grocott's methenamine silver. The organisms were gram-positive and acid-fast negative. Given the clinical and histopathologic findings, actinomycosis was diagnosed. Two weeks later, the patient reported resolution of symptoms. The patient was lost to follow-up. This case highlights an unusual presentation of actinomycosis and the crucial role histopathology plays in diagnosis.

Infecciones abdominales por Actinomyces odontolyticus: comunicación de dos casos / Abdominal infections due Actinomyces odontolyticus: a report of two cases

Resumen Actinomyces spp es una familia de bacilos grampositivos saprofíticos que rara vez producen infecciones en el ser humano. Actinomyces odontolyticus forma parte de la microbiota oral y existen escasos reportes de casos de infecciones asociadas a este microorganismo, principalmente de localización oral, torácica, pélvica y bacteremias. Estas infecciones se caracterizan por ser recidivantes y causar abscesos y trayectos fistulosos. Su aislamiento microbiológico es difícil ya que la mayoría de los equipos automatizados no identifican la especie de Actinomyces, por lo que técnicas como MALDI-TOF MS resulta de gran ayuda en el diagnóstico definitivo. Finalmente, el tratamiento antibacteriano debe ser prolongado, acompañado del drenaje quirúrgico de las colecciones. Presentamos dos casos de infección abdominal recurrente por A. odontolyticus, en pacientes inmunocompetentes, con tratamiento exitoso.

Abstract Actinomyces spp is a family of saprophytic gram-positive rods that rarely cause infections in humans. Actinomyces odontolyticus is part of the oral microbiota and there are few case reports of infections associated, mainly oral, thoracic, pelvic involvement and bacteremia. These infections are characterized by being recurrent and causing abscesses and fistulous tracts. Microbiological isolation of the microorganism is difficult because most of the automated identification equipment does not detect the Actinomyces species. The use of identification techniques such as MALDI-TOF MS is a great help in the definitive diagnosis. Finally, antibacterial treatment should be prolonged, and accompanied by surgical drainage of the collections. We report two cases of recurrent abdominal infection by A. odontolyticus, in immunocompetent patients, with successful treatment.

Actinomycosis in a gray four-eyed opossum (Philander opossum) caused by a novel species of Schaalia.

BACKGROUND: Infective lesions of the jaws and adjacent tissues (lumpy jaw disease, LJD) have been recognized as one major cause of death of captive macropods. Fusobacterium necrophorum and Actinomyces species serve as the main source of LJD in kangaroos and wallabies. Currently, little is reported about LJD or similar diseases in opossums. CASE PRESENTATION: Here we report a case of actinomycosis resembling the entity lumpy jaw disease in a gray four-eyed opossum, caused by a novel species of Schaalia. A 2.8 year old male Philander opossum was presented with unilateral swelling of the right mandible. After an initial treatment with marbofloxacin, the opossum was found dead the following day and the carcass was submitted for necropsy. Postmortem examination revealed severe mandibular skin and underlying soft tissue infection with subsequent septicemia as the cause of death. Histological examination demonstrated Splendore-Hoeppli phenomenon, typically seen in classical cases of actinomycosis. Bacteriology of liver and mandibular mass yielded a previously undescribed species of Schaalia, whose 16 S rRNA gene sequence was 97.0 % identical to Schaalia canis. Whole genome sequencing of the opossum isolate and calculation of average nucleotide identity confirmed a novel species of Schaalia, for which no whole genome sequence is yet available. CONCLUSIONS: The herewith reported Schaalia infection in the gray four-eyed opossum resembling classical actinomycosis gives a novel insight into new exotic animal bacterial diseases. Schaalia species may belong to the normal oral microbiome, as in macropods, and may serve as a contributor to opportunistic infections. Due to the lack of current literature, more insights and improved knowledge about Schaalia spp. and their pathogenicity will be useful to choose appropriate therapy regimens and improve the treatment success rate and outcome in exotic and endangered species.

[The role of piezosurgery in the treatment of a rare case of superinfected cemento-osseous dysplasia caused by actinomyces: a case report]. / L´intérêt de la piézochirurgie dans le traitement d'une dysplasie cémento-osseuse surinfectée par actinomycose: à propos d'un cas.

Cemento-osseous dysplasia is a benign fibro-osseous lesion affecting the alveolar bone. It is classified into three forms: periapical, focal or florid dysplasia. It is often asymptomatic and fortuitously discovered during a routine radiological examination. However, it may become symptomatic after superinfection, after patient's exposure to oral bacterial flora. We here report a case of florid cemento-osseous dysplasia associated with actinomycosis of bone in a 53-year-old Tunisian woman. This superinfection has been rarely reported in the literature; Boolean Searching on PubMed for the keywords "cemento-osseous dysplasia AND actinomyces" displays a single article (Smith et al. 2011). The treatment of actinomycosis infection often requires long-term antibiotic therapy, sometimes associated with surgical debridement, as in the case of this patient who underwent piezosurgery to treat dysplasia and necrotic bone.

Lung adenocarcinoma and pulmonary actinomycosis: a cautionary tale.

BACKGROUND: Pulmonary actinomycosis is a rare and slowly progressive bacterial infection that is often mistaken for lung cancer. Multiple case reports caution against premature diagnosis of malignancy without proper consideration of potential Actinomyces infection. However, no cases in the English literature have been reported that demonstrate the possible coexistence of Actinomyces and lung cancer. CASE DESCRIPTION: We present two cases of patients with culture-positive Actinomyces who were later found to have concomitant biopsy-proven lung adenocarcinoma. CONCLUSIONS: In the workup of a newly identified lung mass, positive culture for Actinomyces does not rule out an underlying malignancy.

Evaluation of Ultrasound Biomicroscopy Combined with Color Doppler Flow Imaging in the Diagnosis of Primary Lacrimal Canaliculitis.

Purpose: To explore the performance of ultrasound biomicroscopy (UBM) and color Doppler flow imaging (CDFI) in the diagnosis of primary lacrimal canaliculitis.Methods: Subjects with relevant symptoms of canaliculitis were prospectively recruited. UBM and CDFI were performed for presumptive diagnosis. Microbiology and histopathology were performed for definitive diagnosis.Results: A total of 37 cases were recruited, including 25 cases of canaliculitis and 12 cases of non-canaliculitis. Pathogens were isolated in 13 canaliculitis cases, and the leading pathogens were Actinomyces (4 cases) and Streptococcus (4 cases). UBM and CDFI identified 24 canaliculitis cases (sensitivity = 96%) and 11 non-canaliculitis cases (specificity = 92%). The predictive factors for canaliculitis were lumen wall thickness >0.25 mm (P = .019) and intracanalicular concretions (P = .010). Other typical features were enlarged lumen (2.16 ± 0.25 mm) and hot-wheel sign-on CDFI (84%). These image findings were congruent with histopathologic changes.Conclusion: Ultrasonography is a valuable tool to assist the diagnosis of canaliculitis.(Clinical trial registration number: ChiCTR1900025411).

Mixed infection of Actinomyces israelii and Fusobacterium nucleatum presenting as a neck mass.

This report presents the case of a mixed infection of Actinomyces israelii and Fusobacterium nucleatum, presenting as an extensive neck mass progressing through tissue planes and causing bony destruction. Despite multiple abscess aspirates, imaging and serological investigations, the causative organisms proved elusive over the course of the patient's long admission, only to be identified postdischarge. The patient was successfully initiated on a prolonged course of intravenous antibiotics and did not suffer from any complications. This report aims to raise awareness of the presentation, pathogenicity and treatment of Actinomyces and Fusobacteria infections, given a notable difficulty in diagnosis.

Pulmonary actinomycosis diagnosed by radial endobronchial ultrasound coupled with metagenomic next-generation sequencing: A case report and brief literature review.

Pulmonary actinomycosis (PA) is an uncommon pulmonary infectious disease that often is misdiagnosed. Metagenomic next-generation sequencing (mNGS) is a highly sensitive and culture-independent new molecular technology for precise infectious disease diagnosis. Here we report a PA case diagnosed by the combination of a radial endobronchial-ultrasonography guide sheath (R-EBUS-GS) and mNGS, along with a brief review of the literature.

[Pulmonary actinomycosis in children: report of two Peruvian cases]. / Actinomicosis pulmonar en niños: reporte de dos casos peruanos.

INTRODUCTION: Actinomycosis is a rare infectious disease caused by Gram-positive bacteria. The most common species is Actinomyces israelii. Among its forms of presentation, the thoracic is the least frequent. CASE PRESENTATION: We report two patients with thoracic actinomycosis, 8 and 13 years old, from different geographical areas of Peru. The first case had empyema necessitans and the second, lung consolidation and recurrent hemoptysis. Both had a certain degree of difficulty in their diagnosis but responded favorably to antibiotics and surgical treatment. The diagnosis was based on the histopathological study. However, we were not able to ascertain the species of actinomyces. CONCLUSION: Thoracic actinomycosis is rare in children and presents as a parenchymal lesion with possible fistulization to the chest wall. This article is one of the few in the Peruvian literature, constituting a contribution to the knowledge of the disease and its management in pediatrics.

INTRODUCCIÓN: La actinomicosis es una enfermedad infecciosa poco frecuente, ocasionada por una bacteria Gram positiva. La especie más común es Actinomyces israelii. Dentro de sus formas de presentación, la torácica es la menos frecuente. PRESENTACIÓN DE CASOS: Reportamos dos pacientes con actinomicosis torácica de 8 y 13 años de diferentes zonas geográficas de Perú. El primer caso tuvo empiema necessitatis y el segundo, consolidación pulmonar y hemoptisis recurrente. Ambos tuvieron cierto grado de dificultad en su diagnóstico, pero con una buena respuesta al tratamiento antibiótico y quirúrgico. El diagnóstico fue mediante estudio histopatológico. Sin embargo, no se pudo identificar la especie de Actinomyces. CONCLUSIÓN: La actinomicosis torácica es poco frecuente en niños y se presenta como una lesión parenquimal con posible fistulización a la pared torácica. Este es uno de los pocos casos reportados en la literatura peruana, constituyendo una contribución al conocimiento de esta enfermedad y su manejo en pediatría.