A 45-year-old man visited our hospital on May 12, 2021, due to hemoptysis with a four-month duration. The patient had a history of hypertension, diabetes, lipid metabolism disorders and coronary heart disease. In 2019, he experienced sudden cardiac death and required endotracheal intubation and tracheotomy, but he survived; the patient had a higher limb muscle tone and minor cognitive impairment after taking aspirin for a long time. Four months prior, he experienced recurrent bouts of blood-tinged sputum. Laboratory parameters were within the normal limits. Computed tomography (CT) scans showed consolidation of the outer basal segment of the left lung's lower lobes and a few cord shadows surrounding it. The results of the clinical examination were inconclusive. He was admitted to a local hospital for a trial of antibiotics and hemostasis, and his condition quickly improved.
He subsequently visited our hospital for recurrent hemoptysis and deterioration and ceased taking aspirin. On admission, his physical symptoms were normal. The white blood cell count was 10.4 x109/L, the percentage of neutrophils was 78%, the C-reactive protein level was 15 mg/L, and the procalcitonin level was 0.03 ng/mL. The serology for HIV was negative. Chest CT showed consolidation of the outer basal segment of the left lower lobe, measuring 2.8 x3.0x 3.5 cm (Figure 1A and B). To stop the haemorrhage, bronchial artery embolization was performed, and the patient was treated with intravenous phentolamine, tranexamic acid, and haemagglutin. The tumour markers (CEA, CYFRA21-1, SCC, NSE, proGRP) were normal. Additional tests were performed, including the T-cell spot test for tuberculosis infection, cryptococcal antigen tests, G-tests, galactomannan antigen detection tests, extractable nuclear antigen tests, and anti-neutrophil cytoplasmic antibody tests, which were within the normal limits. Antinuclear antibody positivity was 1:100. For diagnosis, bronchoscopy with R-EBUS, bronchial brushing (BB), a transbronchial biopsy (TBB), and bronchial washing were performed. The specimens were sent to the lab and pathologist as soon as possible; however, the results of the pathological examination only showed inflammation and a small amount of necrosis in the bronchial mucosa, with no indication of malignancy. Moreover, conventional cultures for bacterial, fungal, and tuberculosis infection were all negative. He underwent a second bronchial artery embolization for massive hemoptysis (approximately 400 mL) on June 12, 2021. Persistent hemoptysis led to repeat chest CT, which revealed a reduced consolidation lesion measuring 2.0 cm x 2.6 cm x 3.0 cm, with ground glass density foci and cords surrounding the lesion (Figure 1C and D). We considered that the lesion was complicated with bacterial infection and administered amoxicillin clavulanate potassium orally. 
Hemoptysis recurred on June 29. The patient had intermittent bouts of massive hemoptysis (>150 mL) every few hours, and intravenous injection of hemostatic drugs was ineffective. The third bronchial artery embolization showed no bleeding. On July 6, 2021, the patient experienced extensive hemoptysis, which was voluminous, and bright red; the estimated volume of blood was 700 mL. CT showed an increase in the size of consolidation to 2.0 cm x 2.7 cm x 3.1 cm and bilateral ground-glass opacities (Figure 1E and F). Bronchoscopy revealed the presence of old blood clots in the upper and lower left lungs, as well as scattered evidence of recent blood in the trachea. We decided to perform emergency VATS. The left lower lung was resected. The patient did not have hemoptysis after the operation and was given meropenem, which was degraded to ceftriaxone. Histopathology revealed a grey-white area with a range of 1.8x1.5x1.3 cm in the gross lung tissue, bronchiectasis in the lung, disintegration of the tube wall, and acute inflammatory exudate in the lumen. Under a microscope, chrysanthemum shapes in the lumen and dense centres of intertwined, branched hyphae surrounded by radially-arranged eosinophilic long hyphae were observed; Glan staining was positive, and epithelioid cells surrounded the granules, macrophages, lymphocytes, and other inflammatory cells, which were positive for hexamine silver and Periodic Acid-Schiff stain (Figure 2). The final diagnosis was pulmonary actinomycosis. His condition was stabilized with oral amoxicillin following discharge. He has remained in a stable condition for a year while receiving routine follow-up.