Pericardial actinomycosis

A man in his 50s, with a history of night sweats and weight loss, presented acutely with dyspnoea and chest pain. Imaging revealed right middle lobe consolidation and a large pericardial effusion. The diagnosis of actinomycosis was made using endobronchial ultrasound-guided sampling from the pericardial effusion. An orthopantomogram demonstrated that the source was a large cavity in the left lower wisdom tooth. This tooth was extracted before the completion of his antibiotic course, and the patient made a full recovery. Cardiac actinomycosis is rare, and there are few case reports describing endobronchial ultrasound-guided sampling of pericardial fluid.

A 13-Year-Old Boy with Chest Wall Actinomycosis Mimicking Ewing Sarcoma on Imaging

BACKGROUND Actinomyces, a filamentous, branching, anaerobic gram-positive bacillus, typically found as a commensal organism in the oral cavity, can lead to rare chronic bacterial infections in various anatomical regions. Chest wall involvement represents an uncommon presentation, posing significant diagnostic challenges. This report focuses on the case of a 13-year-old boy presenting with chest wall actinomycetoma that closely resembled Ewing sarcoma on imaging. CASE REPORT We present the case of a 13-year-old male with no previous medical history who presented to the Emergency Department with progressive left-sided chest pain following a sports-related fall. Physical examination revealed mild swelling and tenderness on the left anterior chest wall. A chest computed tomography (CT) scan revealed a large tumor involving the lower left chest wall, suggesting Ewing sarcoma. However, a histopathological examination unexpectedly confirmed actinomycosis of the chest wall. Intravenous penicillin G was promptly initiated for 4 weeks. A follow-up CT scan after 4 weeks of therapy demonstrated a significant response with notable reduction in the size of the chest wall mass. The patient then continued with maintenance therapy using oral amoxicillin for 12 months. Throughout this period, complete resolution of the chest wall mass occurred, with no significant adverse events or complications observed. CONCLUSIONS This case highlights the importance of considering uncommon differential diagnoses like chest wall actinomycosis in patients presenting with chest wall masses. The diagnostic complexities associated with this rare condition emphasize the need for a comprehensive evaluation strategy, incorporating histopathological examination and imaging.

Extensive actinomycosis with intracranial and mediastinal involvement: a therapeutic challenge

Central nervous system (CNS) involvement by actinomycosis is rare, seen in 2%–3% cases. It mostly spreads to CNS by haematogenous route from a distant primary site such as oral cavity, lung, abdomen or pelvis. Direct CNS extension can also occur. It mostly presents as brain abscess, meningoencephalitis, actinomycetoma, subdural empyema and epidural abscess. We report one case of extensive actinomycosis having intra and extraparenchymal CNS, spinal canal, retropharyngeal and mediastinal involvement. Due to such widespread extension and involvement of vital areas, complete surgical debulking was not possible. In addition to therapeutic resistance to conventional antibiotics, repetitive negative cultures posed significant difficulty in the case management.

Pancreatic actinomycosis treated by antibiotics after diagnosis using endoscopic ultrasound-guided fine-needle biopsy

A 71-year-old man who had undergone total gastrectomy, partial pancreatectomy, and splenectomy with Roux-en-Y reconstruction for gastric cancer was referred for a possible pancreatic tail tumor. Contrast-enhanced computed tomography showed mold-like, poor contrast lesion in the dilated main pancreatic duct in the pancreatic tail. Endoscopic ultrasonography revealed a slightly hyperechoic solid lesion that occupied the lumen of the main pancreatic duct. Linear calcification was observed in the lesions on both computed tomography and endoscopic ultrasonography, and endoscopic ultrasound-guided fine-needle biopsy was performed. Histopathology revealed sulfur grains and inflammatory infiltrates with no malignant findings. We also performed an anaerobic culture using fine-needle biopsy specimens, and Actinomyces meyeri was detected in the culture results. After confirming susceptibility, oral administration of amoxicillin was initiated. After 8 months of treatment, the size of the lesion slightly decreased, and the antibiotics treatment is still ongoing. This shows that such cases could be diagnosed based on histological findings and anaerobic culture using a fine-needle biopsy specimen, and unnecessary surgery may be avoided. In the case of tumors developed in the residual pancreas without typical malignant imaging findings, pancreatic actinomycosis should be considered as a differential diagnosis.

18F-FDG PET/CT of Hepatosplenic Actinomycosis After Laparoscopic Cystojejunostomy for Pancreatic Pseudocyst

ABSTRACT

We report the 18F-FDG PET/CT appearance of abdominal actinomycosis in a 48-year-old immunocompetent woman with a history of laparoscopic cystojejunostomy for pancreatic pseudocyst previously. 18F-FDG PET/CT demonstrated multiple hypermetabolism in the liver, spleen, cystojejunostomy anastomosis, greater omentum, and umbilical region. Actinomycosis was verified by biopsy. Hepatosplenic actinomycosis secondary to cystojejunostomy is extremely rare and easily to be misdiagnosed. PET/CT is helpful for auxiliary diagnosis, guiding biopsy, and exploring the extent of the disease.

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.

Microstructural analysis of bony alterations in a historic case of actinomycosis

OBJECTIVE

Actinomycosis infection of bone is rare and its diagnosis challenging. Here, we aim to identify and verify its microstructural features and the potential value for differential diagnosis.

MATERIALS

We investigated the dry preparation of the lumbar vertebrae and pelvic ring of a purported case of actinomycosis documented by a post-mortem examination in 1891.

METHODS

Macroscopic inspection, conventional radiology, μCT, 3D reconstruction, and histological examination were employed.

RESULTS

All approaches revealed new periosteal bone deposition with increased vascularisation of the os coxa, vertebrae, and sacrum. The μCT revealed cortical loss underneath the new bone formation; the 3D reconstruction and histological examination revealed plexiform bone and granular structures.

CONCLUSIONS

The plexiform bone is the result of reactive rapid growth and remodelling processes, and is consistent with pathomorphological findings summarised in the autopsy report (soft tissue abscesses and formation of fistulas caused by "Actinomycosis intestine et ossis ilei sin.").

SIGNIFICANCE

This is the first case of a historically documented case of actinomycosis infection investigated by μCT and histology. Different degrees of tissue damage and inflammatory reaction in form of plexiform bone, which has not been reported previously, was identified.

LIMITATIONS

The noted bone tissue modifications are not solely pathognomic of actinomycosis; they characterise other diseases, as well. Histological evaluation is not appropriate for identifying the aetiology of the granular structures observed here; but clinically such aggregations appear in tissue affected by actinomycosis.

SUGGESTIONS FOR FURTHER RESEARCH

Histochemical and molecular-genetic analyses are obligatory to affirm the diagnosis based on micromorphological features.

Actinomycotic Osteomyelitis of the Hand and Wrist Treated with Pharmacotherapy Alone: A Case Report

CASE

Primary infection by Actinomyces is uncommon because susceptibility to infection requires breakdown of the normal protective mucosal barrier. Furthermore, involvement of the upper extremity is rare. This case report presents clinical, radiological, and pathological findings in a 26-year-old patient with actinomycosis of the hand that was treated successfully by pharmacotherapy alone without any surgical debridement.

CONCLUSION

Primary actinomycoses of the hand and upper extremity present as a challenging condition. It requires a high index of clinical suspicion and histopathologic diagnosis to guide treatment, typically involving antimicrobial therapy. This case highlights the usefulness of conservative treatment with antimicrobial therapy without surgical debridement.

[Thoracal actinomycosis - a diagnostic challenge]

Actinomycotic infection of the chest structures is rare but can be serious. Diagnosis is difficult, since both culture of the bacterium and pathological investigation require special methods. Investigations therefore usually take many months before the correct treatment can be started. The most common differential diagnosis is a chest malignancy. Treatment is long-term antibiotics. We here present three cases which illustrate the clinical and radiological findings and the diagnostic difficulties.

[Primary intestinal actinomycosis in ilium and colon. A case report and review of the literature]

Actinomycosis is a chronic, suppurative, inflammatory granulomatous disease caused by gram positive anaerobic filamentous bacteria of the genus Actinomyces, most frequently Actinomyces israelii. We report a case of a 42-year-old male presenting with abdominal pain, a 10kg weight loss and a fixed mass in the epigastrium. Tomography revealed dilatation of the intestinal loops and thickening of the colon walls; the coexistence of these two findings suggested a lymphoproliferative process. The tumour, ileum fragment and colon were surgically removed; these were adherent to the serosal fibro-adipose tissue. Microscopically, abundant polymorphonuclear infiltrate and grains of bacteria compatible with Actinomyces spp.were seen.

Pulmonary Actinomyces graevenitzii Infection Diagnosed by Bronchoscopy using Endobronchial Ultrasonography with a Guide Sheath

A 75-year-old man visited our hospital complaining of a low-grade fever, dry cough, and chest abnormal shadow. Chest computed tomography revealed a nodule with a cavity in the right upper lobe. Endobronchial ultrasonography (EBUS) of the lesion suggested that the lesion was benign. Actinomyces graevenitzii was cultured from the specimen obtained by bronchoscopy using endobronchial ultrasonography with a guide sheath technique and was identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and 16S rRNA sequencing. The patient was treated with intravenous ampicillin; subsequently, his condition improved. We believe that careful observation of EBUS findings may be useful for the differential diagnosis.

Brain abscess caused by chronic invasive actinomycosis in the nasopharynx: A case report and literature review

RATIONALE

Actinomycosis is a rare anaerobic, gram-positive bacterial infection caused by Actinomyces, which is part of the normal flora in the oral cavity and respiratory and female genitourinary tracts. The cervicofacial area is the most common site of involvement, and involvement of the central nervous system is rare.

PATIENT CONCERNS

We report a case involving a 51-year-old woman who developed an actinomycotic brain abscess 15 months after the treatment of noninvasive nasopharyngeal actinomycosis, which recurred as an invasive form.

DIAGNOSES

Histopathological examination of the surgical specimens revealed actinomycosis.

INTERVENTIONS

The patient was treated by surgical drainage of the brain abscess and long-term antibiotic treatment.

OUTCOMES

Follow-up brain imaging performed 12 months after surgery showed complete resolution of the brain abscess, and there were no further signs or symptoms of infection.

LESSONS

Physicians should be aware of the typical clinical presentations of cervicofacial actinomycosis. Moreover, they should know that actinomycosis may mimic the process of malignancy at various anatomical locations.

[Urachal Actinomycosis : A Case Report]

The patient was a 66-year-old woman who was examined by a local physician for the chief complaint of a mass palpable in the left lower abdomen. Abdominal plain computed tomography (CT) indicated a subcutaneous mass extending continuously from the apex of the bladder to the retropubic space, and she was referred to our medical department. Tumor markers were normal, and cystoscopic examination indicated no clear findings. Abdominal contrast-enhanced CT and plain abdominal magnetic resonance imaging results led to suspicion of actinomycosis. An open biopsy was performed on the subcutaneous mass, and subsequent histopathological testing led to a definitive diagnosis of actinomycosis. After 2 weeks of antibiotic therapy, the mass had diminished on CT. There has been no relapse approximately 24 weeks after discontinuation of the antibiotic therapy.

Pulmonary actinomycosis masquerading as lung cancer: A case report

Pulmonary actinomycosis is a rare yet important and challenging diagnosis to make. It is commonly confused with other lung diseases, such as tuberculosis and bronchogenic carcinoma, leading to delay diagnosis or misdiagnosis. A 49-year-old man presented with a chronic cough, hemoptysis, and pleuritic chest pain. His initial imaging studies including computed tomography (CT) was suggestive of bronchogenic carcinoma. A subsequent CTguided biopsy was consistent with pulmonary actinomycosis and excluded the possibility of bronchogenic carcinoma. He was treated with antibiotic therapy and achieved remission with complete radiological resolution upon follow-up.

Pulmonary actinomycosis - the great imitator

Pulmonary localisation represents only 15% of all cases of actinomycosis. The clinical symptoms and radiological changes of this disease are non-specific and sometimes it can be misdiagnosed, usually as tuberculosis, lung cancer or lung abscess. In the reported case, what might look like the lung cancer, finally turned out to be actinomycosis. The interesting case is presented of lung actinomycosis in a 77-year-old farmer, admitted to the Department of Pneumonology, Oncology and Allegology in Lublin due to a massive haemoptysis. CT scan of the chest showed, apart from other changes, the spicular consolidation in the right lung which aroused oncology vigilance. The diagnostic path, which was a real medical challenge, led to the diagnosis of actinomycosis. The process of diagnosis and consequent treatment, which led to the complete regression of clinical and radiological changes, is presented.

Pulmonary actinomycosis masquerading as aspergilloma

We report a case of a 34-year-old man who was initially treated as community acquired pneumonia following a three-month-history of productive cough, loss of weight and loss of appetite. However, three months after discharged from the hospital, he presented again with worsening respiratory symptoms and radiological evidence of a lung cavitation with intracavitary lesion resembling an aspergilloma associated with surrounding consolidation. Unfortunately, he remained symptomatic despite on antifungal therapy. The repeat computed-tomography demonstrated persistent cavitating lesion with development of necrotising pneumonia. He underwent lobectomy and the histopathological analysis of the resected specimen however revealed the diagnosis of actinomycosis.

[Genital actinomycosis and pelvic abscesses in a woman with a 13-year-old intrauterine device]

A 55-year-old woman who had had the same intrauterine device (IUD) for 13 years was referred to the gynaecology outpatient clinic due to constitutional symptoms, abdominal pain and vaginal discharge. Diagnostic imaging showed multiple pelvic abscesses, and severe chronic endometritis with Actinomyces was found in an endometrial biopsy. The patient underwent surgical drainage of the accessible abscesses and started long-term antibiotic treatment. This case report illustrates that actinomycosis is an important differential diagnosis in symptomatic women with IUD and suspected gynaecologic malignancy.

Pulmonary Actinomycosis Mimicking Pulmonary Aspergilloma and a Brief Review of the Literature

Pulmonary actinomycosis is a rare pulmonary infection that often exhibits unspecific symptoms and radiological findings. We herein report a case of pulmonary actinomycosis that mimicked pulmonary aspergilloma in an immunocompetent patient.

[Actinomycotic brain abscess in immunocompetent patient]

BACKGROUND

The actinomyces is germ commonly found in the normal flora of the oral cavity and gastro-intestinal and uro-genital tracts. Involvement in other locations is a very uncommon event.

OBJECTIVES

To describe a patient with an actinomicotyc brain abscess CLINICAL CASE: We report the case of a patient who suffered a seizure and decreased level of consciousness. Imaging tests revealed the presence of lesions both in the lung and in the brain. An urgent craniotomy was performed and the diagnosis of actinomicotyc abscess was obtained.

CONCLUSION

We describe the differential characteristics of this type of infection, discussing the diagnostic process and management in detail.

Actinomycosis of the abdominal wall after cholecystectomy: transferral theory

Abdominal actinomycosis is a rare disease caused by Gram-positive anaerobic Actinomyces bacteria. Here, we present a patient with an intrauterine contraceptive device who developed a long lasting and unexplained recurrent, painful abdominal swelling a few months after a laparoscopic cholecystectomy.

[Primary omental actinomycosis]

We report a case of omental actinomycosis in a female patient with an intrauterine device. A computed tomography had shown an inflammatory tumour in the abdomen. The patient was treated with laparoscopic resection of the tumour and prolonged antibiotic therapy. Abdominal actinomycosis should be considered as a differential diagnosis in patients with abdominal symptoms and unspecific clinical, radiological and laboratory findings. Definitive diagnosis of actinomycosis requires histological examination of affected tissue. Laparoscopic resection seems feasible as an alternative to open surgery.

Refractory primary hepatic actinomycosis with direct infiltration to the diaphragm and thorax: the usefulness of contrast-enhanced ultrasonography

An 80-year-old man was admitted to our hospital with a diagnosis of primary hepatic actinomycosis determined based on a percutaneous aspiration biopsy. The abscesses and state of liquefaction were easily and effectively visualized on contrast-enhanced ultrasonography. Ampicillin/sulbactam was administered; however, lesions of hepatic actinomycosis suddenly infiltrated the diaphragm and right thorax six months later. A drainage tube was inserted into the right thoracic space, and the pleural effusion gradually decreased. The patient received continuous antibiotic therapy for nearly two years and remained free of hepatic actinomycosis on follow-up more than one year later.

Accidentally ingested foreign body associated with liver actinomycosis: the diagnostic value of imaging

Accidental ingestion of foreign bodies is a relatively common situation, in the large majority of cases being followed by an unobserved passing of the objects through the digestive tract and their elimination in about a week. We present a patient with liver actinomycosis developed in relation with a gastric (antral) perforation secondary to accidental foreign body ingestion. The complexity of the case raised many problems concerning the imaging diagnosis, especially due to the pseudotumoral aspect of the liver lesion, which extensively involved the retroperitoneal area, the stomach and the pancreas. However, the presence of an image suggesting a foreign body into the gastric wall, in correlation with clinical, biological, morphological and imaging studies solved the case.

[Disseminated pulmonary actinomycosis with hepatic injury: a misleading form mimicking a polymetastatic picture]

INTRODUCTION

Thoracic actinomycosis, caused by bacteria of the Actinomyces genus, is a rare infection, with poor prognosis if untreated, whose clinical and radiological picture is misleading, which can simulate a tumoral or tuberculous disease.

CLINICAL CASE

This is a case of generalised pseudotumoral pulmonary actinomycosis in a non-smoking, non-drinking 48-year-old man, who for one month has been presenting a cough with haemoptoic sputum, dyspnoea associated with fever and a deterioration in general condition. The clinical examination discovered weight loss, diffuse crackling rales and multiple dental caries. Biologically, he presented an inflammatory syndrome. The radiological imaging and lung and liver CT-scans discovered a peripheral lung mass right side associated with multiple nodular cannon-ball opacities, multiple liver lesions of metastatic appearance. The bacteriological examination of the bronchoalveolar lavage fluid (Gram stain and culture) and the transparietal biopsy of the lung mass confirmed the presence of Actinomyces. Progress under treatment with 10 million international units of parenteral penicillin G daily over a period of six weeks substituted by three grams of amoxicillin/clavulanic acid daily over a period of 12 months and following an oral preparatory procedure was favourable. The thoraco-abdominal scan carried out three months after the treatment showed that the lesions had completely disappeared.

CONCLUSION

Our case illustrates the diagnostic difficulty of actinomycosis particularly faced with a picture of multiple lung and liver metastasis. Hence, the importance of a histological and bacteriological examination of samples. The prognosis of this complaint is generally good following well-managed, prolonged treatment; and the prognosis peculiar to disseminated forms is less certain.

[Pulmonary actinomycosis - a case report]

Pulmonary actinomycosis is a rare disease caused by Actinomyces sp. Its symptoms and radiological findings are not characteristic, so the diagnosis might be difficult to establish. We report a case of a 59 year old male, who developed bronchopulmonary Actinomycosis due to poor dental hygiene. The infectious process affected lung parenchyma and infiltrated chest wall causing multifocal sternal osteolisis and multiple cutaneous fistulas. The radiological findings sugested neoplasmatical process. The diagnosis was based on histopatological findings of fistular scrapes. The material contained Actinomyces colonies. Afler 6 months of antibiotic therapy the patient's state improved and the cutaneous fistulas healed. Radiological finding revealed partial resolution of the lung infiltration.

[Pulmonary actinomycosis. Fine needle aspiration diagnostic]

We present four cases of pulmonary actinomycosis in patients over 40 years of age, two of them with chronic obstructive pulmonary disease (COPD), showing an increase in productive cough, episodes of dyspnea, hemoptysis and long-term fever. Routine chest radiographs revealed segmental air-space consolidation, suggestive of unresolved pneumonia or neoplasm. Computed tomography (CT) scan showed similar findings to the ones previously described. Sputum cultures for mycobacteriae and Mantoux tests were constantly negative. Due to the poor clinical and radiodological outcome of the patients, a fine needle aspiration (FNA) was made to rule out a neoplasm. Tridimensional filamentous colonies of Actinomyces were observed in cytology. Antibiotic treatment resulted in an improvement of symptoms. The follow-up showed a decrease of the consolidation areas. Pulmonary actinomycosis is rare nowadays and clinical symptoms are unspecific and can be confused with a neoplasm process. Therefore, in patients with risk factors, symptoms of subacute pneumonia and radiologic findings of consolidation, it is advisable to consider pulmonary actinomycosis as a diagnostic possibility. It is a treatable disease and its correct diagnosis by FNA, avoids performing invasive diagnostic tests, delays in the diagnosis and allows for a complete cure by antibiotic therapy.

Radiographic evaluation of periapical lesions with and without biopsy-proven actinomyces: a pilot study

OBJECTIVE

To explore the feasibility of identifying potential radiometric differences in periapical radiolucencies with and without actinomycotic colonization as seen on periapical radiographs using histopathology for ground truth.

METHOD AND MATERIALS

Periapical radiographs demonstrating apical lesions with and without biopsy-proven actinomycosis were included in the study. Lesion sizes were estimated on standardized images using anatomical reference points. The reading session was repeated after 2 weeks, and mean lesion sizes were calculated. All measurements were made by a single, calibrated observer.

RESULTS

The mean dimension of lesions with actinomyces was 13.51 × 16.43 mm, while lesions without actinomyces had a mean size of 10.24 × 11.27 mm.

CONCLUSION

Apical lesions with biopsy-proven actinomyces may be larger in dimension than those without bacterial colonization. Further controlled studies are required to confirm this finding.

Pancreatic actinomycosis as a cause of retroperitoneal fibrosis in a patient with chronic pancreatitis. Case report and literature review

CONTEXT

Chronic alcoholic pancreatitis is a debilitating disease that is often complicated by pseudotumoral changes of the pancreas, retroperitoneal fibrosis, and pancreatic cancer. Actinomycosis is an uncommon intra-abdominal infection and its association with chronic pancreatitis has been rarely reported.

CASE REPORT

We present a case of a patient with progressive long standing chronic pancreatitis who develops pseudo-tumoural changes and retroperitoneal fibrosis associated with actinomycosis.

CONCLUSION

This is a rare presentation of actinomycosis, posing a diagnostic challenge to the clinician, with important therapeutic implications.

Tonsillolithiasis with actinomycotic infection: a case report

Tonsillar calcifications, tonsilloliths, are not rare conditions for routine ear nose throat examinations. Their size vary from barely visible to the pea size and they should be kept in mind in the differential diagnoses of radiopaque lesions in this region. We report a 42-year-old male patient who had a large tonsillolith together with an actinomycotic infection of tonsillar region. The patient complained about recurrent tonsillar infections. In his routine ear nose throat examination a large tonsillolith, lodged in the right palatine tonsil, was observed. The patient underwent tonsillectomy under general anesthesia. Histopathologic evaluation confirmed the diagnosis of tonsillolith. Interestingly, actinomycotic infection was observed. The pathogenesis of tonsilloliths is not completely defined. Many investigators have suggested that tonsilolliths originate as a result of recurrent tonsillar infections. Our purpose is to remind the tonsillolith in the differential diagnoses of chronic tonsillar region pathologies.

Abdominal lump with a rare pathology

Actinomycosis is one of the rarest pathologies causing intra-abdominal lump in the normal population. Diagnosis is often difficult because of the least suspicion and failure in the pre-operative diagnosis even by taking the aid of modern imaging techniques like Ultrasonogram, CT scan or MRI. Even FNAC may be misleading because of the technical problems and proper interpretation of cytology. Diagnosis is usually made during laparotomy by an experienced Surgeon and finally by the histopathological examination of the resected specimen. We have come across three patients with actinomycosis presenting with intra-abdominal lumps, two as appendicular lumps and 3rd one as a lump of left colonic origin in our institute over the last two years. Ultrasonogram examination revealed lump of gut origin in all the three cases. FNAC in one case revealed the lump as a low grade sarcoma. Laparotomy, excision and or resection of the lumps along with the segment of involved gut with subsequent histopathology revealed these cases as actinomycosis. We report these cases for its extreme rarity and a puzzling pre-operative diagnostic dilemma.

[A case of endobronchial actionomycosis evaluated by FDG-PET]

In April 2005, a 78-year-old man was admitted to our hospital because an abnormal chest shadow had been noted on a medical examination. Our investigation revealed primary squamous cell lung carcinoma in the right lower lobe (stage IIIA). Right middle and lower lobectomies including resection of the chest wall were performed. 18Fluorodeoxyglucose-positron emission tomography (FDG-PET) conducted 18 months later demonstrated nodular lesions with intense FDG activity in the right upper lobe and the presence of a post-resection positive bronchial stump. Fiberoptic bronchoscopic examination revealed a pus-coated mass located in the endobronchial lesion, and Actinomyces was identified in a biopsy specimen of the mass. Endobronchial actinomycosis was diagnosed. An FDG-PET examination conducted after the patient was treated with amoxicillin (AMPC) for 2 months, did not indicate any FDG activity in the endobronchial lesion.