BACKGROUND Necrotizing pneumonia (NP) is a severe, life-threatening pediatric pulmonary infection associated with substantial diagnostic and therapeutic challenges, often leading to rapid lung tissue destruction, cavitation, and pleural complications that demand urgent, multidisciplinary clinical management. Flexible bronchoscopy (FB) with bronchoalveolar lavage (BAL) is a well-established tool for pathogen identification, yet the role of medical thoracoscopy in managing refractory pleural effusion in pediatric NP caused by Streptococcus pyogenes, an uncommon but highly virulent pathogen, has not been fully elucidated in clinical practice. CASE REPORT A 7-year-old girl with persistent fever, cough and acute abdominal pain was transferred due to ineffective azithromycin and corticosteroid therapy. Pharyngeal swab detected human metapneumovirus, and FB combined with BAL identified S. pyogenes as the lung pathogen. She initially responded to linezolid plus ceftriaxone but was readmitted 12 hours later with recurrent symptoms. Contrast-enhanced chest computed tomography (CT) confirmed bilateral lower lobe NP with cavitation and pleural effusion. The patient recovered uneventfully after medical thoracoscopy with closed chest drainage, and no adverse outcomes were reported at 1-, 3-, and 6-month telephone follow-ups. CONCLUSIONS This case highlights that FB and BAL are pivotal for the accurate etiological diagnosis of S. pyogenes-induced NP in children, even in the setting of concurrent viral infection, enabling targeted antimicrobial therapy selection. Medical thoracoscopy is a safe and effective minimally invasive intervention for managing refractory pleural effusion and empyema associated with severe pediatric NP, addressing mechanical obstruction and pleural complications that are unresponsive to antimicrobial monotherapy.

Dendriform pulmonary ossification (DPO) is a rare condition characterised by branching bone formation within the lung parenchyma, often associated with fibrotic interstitial lung disease (ILD). We report an asymptomatic man in his 80s with primary biliary cholangitis who presented with bilateral lower-lobe fibrosis and subpleural micronodules on high-resolution CT, initially suggesting granulomatous ILD. Transbronchial lung cryobiopsy revealed fibrosis with intra-alveolar ossification and subsequent bone window high-resolution CT confirmed branching calcified structures, establishing the diagnosis of DPO. This case highlights the importance of considering DPO in fibrotic ILD with subtle nodular findings and demonstrates the utility of transbronchial lung cryobiopsy in the differential diagnosis.

In immunocompetent hosts without healthcare exposure, Pseudomonas aeruginosa is an uncommon pathogen causing community-acquired lung abscesses. These infections are usually polymicrobial and include oropharyngeal flora. We describe a case of a 52-year-old man who had previously been in good health but presented with a four-day history of anorexia, malaise, and fever. Fever (38.0°C), tachycardia (107 bpm), and decreased breath sounds with dullness to percussion over the left lower lung region were noted on physical examination. Significant leukocytosis (11.3 × 10[3]/μL) and elevated C-reactive protein (252.8 mg/L) were found on laboratory investigations. A sizable (9.3 × 9.6 cm) cavitary lesion with peripheral enhancement in the left lower lobe was confirmed by chest radiography and contrast-enhanced computed tomography, consistent with a primary lung abscess. Pseudomonas aeruginosa was identified as the causative pathogen by bronchoscopy and bronchoalveolar lavage, whereas tuberculosis was ruled out by polymerase chain reaction and negative smears. Clinical improvement occurred within 72 hours of initiating targeted intravenous piperacillin-tazobactam 4.5 g every six hours after infectious disease consultation. Without the need for percutaneous drainage, the patient completed a six-week course of antibiotics, including a 14-day intravenous course followed by four weeks of oral ciprofloxacin 750 mg twice daily. This case emphasizes three key lessons: (1) the value of multidisciplinary management in balancing prolonged medical therapy and interventional drainage for large abscesses; (2) the critical role of bronchoscopic sampling in identifying atypical pathogens and guiding targeted antimicrobial therapy; and (3) the importance of maintaining diagnostic suspicion for lung abscess in patients with constitutional symptoms even in the absence of classic respiratory complaints.

Immunoglobulin G4-related disease (IgG4-RD) is a rare systemic fibroinflammatory condition that may affect virtually any organ, including the lungs. Thoracic involvement often occurs with non-specific imaging findings and requires histopathological confirmation. We present the case of a 71-year-old man with a history of T-cell large granular lymphocytic leukaemia and MGUS, who presented with smoking-related interstitial lung disease on high-resolution chest computed tomography (CT) and left lower lobe (LLL) consolidation. Positron emission tomography (PET)/CT revealed hypermetabolic activity in lung consolidations and mediastinal and diaphragmatic lymph nodes. A right diaphragmatic lymph node biopsy showed increased IgG4-positive plasma cells (IgG4/IgG > 40%). Subsequent transbronchial biopsies confirmed the presence of dense lymphoplasmacytic infiltrates, fibrosclerosis and IgG4-positive plasma cells in lung tissue. Given the patient's diabetes, rituximab (RTX) was chosen over corticosteroids. RTX, consisting of four weekly infusions, led to significant clinical improvement and complete metabolic response on follow-up PET/CT. Reporting this case, we would like to emphasise the importance of considering IgG4-RD in the differential diagnosis of atypical thoracic infiltrates and highlight the role of RTX as an effective therapeutic option in patients for whom corticosteroids are contraindicated.

Pulmonary toxoplasmosis is a rare but potentially fatal opportunistic infection, most often reported in HIV-infected individuals. Its occurrence in non-HIV immunocompromised patients-particularly those with hematologic malignancies like multiple myeloma (MM)-is exceedingly rare and diagnostically challenging due to nonspecific clinical and radiologic features. While Toxoplasma gondii infection is typically mild in immunocompetent hosts, it can cause severe disease in immunocompromised populations. A literature review was conducted using PubMed, Scopus, and Google Scholar (January 2000-May 2025) with keywords: 'pulmonary toxoplasmosis,' 'multiple myeloma,' 'non-HIV,' 'immunocompromised,' and 'BAL PCR.' Only English-language case reports and reviews were included, with emphasis on studies from endemic regions and the past five years. We report a 49-year-old Iranian man with newly diagnosed IgG kappa MM who presented with fever, chills, vomiting, and dyspnea. Chest CT revealed a 4.2 × 3.8 cm consolidation in the posterior segment of the right lower lobe. T. gondii infection was confirmed via bronchoalveolar lavage (BAL) through tachyzoite detection on Giemsa stain and molecular identification using qPCR and nested PCR targeting the Gra6 gene. He showed transient clinical improvement and was discharged on hospital day 7. Unfortunately, he died at home within 48 hours due to MM progression, before anti-toxoplasmosis therapy was initiated. This case underscores the diagnostic difficulty of pulmonary toxoplasmosis in non-HIV immunocompromised patients and the importance of molecular BAL testing. Prophylactic measures such as co-trimoxazole should be considered in high-risk MM patients. Guidelines must address screening and management in this vulnerable population.

Mycobacterium heckeshornense is a rare nontuberculous mycobacterium that has been reported sporadically since its first description by Roth et al. in 2000. From the earliest reports, infections have been documented not only in immunocompromised patients or those with underlying lung disease, but also in immunocompetent individuals, with a wide range of clinical manifestations. However, owing to the limited number of cases and their heterogeneity, the full clinical spectrum of this organism has not been clearly defined. We report a case of asymptomatic pulmonary M. heckeshornense infection in a healthy 48-year-old man, incidentally detected by an abnormal chest radiograph during routine health screening. Chest computed tomography revealed a cavitary lesion in the left lower lobe and centrilobular nodules in the right middle lobe. Bronchoscopy demonstrated acid-fast bacilli, and M. heckeshornense was identified from sputum and bronchial lavage cultures using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Treatment with clarithromycin, rifampicin, and ethambutol resulted in marked radiographic improvement. By integrating this case with previously reported pulmonary infections in immunocompetent hosts, we demonstrate that M. heckeshornense infection encompasses a broad clinical spectrum ranging from highly destructive disease requiring surgical intervention to long-standing, subclinical infection. The present case represents the most indolent phenotype reported to date and underscores the importance of considering this rare pathogen even in asymptomatic, immunocompetent individuals.

Rheumatoid arthritis (RA) may present with extra-articular pulmonary manifestations, including rheumatoid lung nodules. Leflunomide is an effective disease-modifying antirheumatic drug, but increasing case reports suggest an association with accelerated pulmonary nodulosis. We describe a 61-year-old woman with long-standing seropositive RA who developed left-sided lower chest pain, generalized weakness, fatigue, and loss of appetite after switching from methotrexate to leflunomide 20 mg/day. CT imaging demonstrated multiple bilateral cavitary nodules predominantly in the lower lobes. Extensive evaluation (bronchoscopy with microbiology, QuantiFERON-TB Gold, and malignancy assessment) was negative, and video-assisted thoracoscopic surgery lung biopsy showed necrotizing granulomatous inflammation consistent with rheumatoid nodules. The leflunomide dose was initially reduced and then discontinued, and methotrexate was reintroduced; at the four-month follow-up, the patient was clinically well without synovitis, and a CT eight months later showed near-complete regression of prior nodules, with residual left basal fibrotic changes containing calcifications and a remaining non-cavitary right lower-lobe nodule. Clinicians should consider leflunomide-associated pulmonary nodulosis in RA patients with new cavitary nodules after excluding infectious and malignant etiologies, and discontinuation of the drug may lead to radiologic improvement.

BACKGROUND Extracorporeal membrane oxygenation (ECMO) serves as a life-sustaining intervention for pediatric patients with severe, reversible respiratory or circulatory failure refractory to conventional therapies, providing temporary cardiopulmonary support to maintain oxygenation, perfusion, and hemodynamic stability. CASE REPORT Following a family argument, a 9-year-old boy fell from the seventh floor, with partial obstruction by a canopy. He presented with immediate loss of consciousness, absent voluntary motor activity, Kussmaul respirations, otorrhagia, and epistaxis. Initial computed tomography (CT) revealed high-attenuation nodules in the right main bronchus, right lower lobe bronchus. Despite endotracheal intubation and supportive measures, oxygenation remained refractory to correction, prompting interhospital transfer. On admission to our unit, imaging revealed high-attenuation opacities in the right middle bronchus and left lower lung. Multidisciplinary consultation was conducted. Under ECMO support, flexible bronchoscopy enabled retrieval of tooth fragments from the right upper lobe and an entire left maxillary first permanent molar from the left lower lobe. Postoperatively, ECMO was successfully discontinued, with the patient exhibiting stable vital signs, and subsequent management was continued. CONCLUSIONS The successful retrieval of dental fragments and an entire tooth via flexible bronchoscopy, facilitated by ECMO support, underscores the critical role of ECMO as a stabilizing platform enabling otherwise high-risk airway interventions in hemodynamically compromised pediatric trauma patients. This case illustrates the strategic implementation of venoarterial ECMO as a salvage therapy in the context of refractory hypoxemia and cardiopulmonary instability, rather than as a routine adjunct to flexible bronchoscopy procedures.

Pulmonary embolism (PE) is a potentially life-threatening condition that classically presents with chest pain, tachycardia, and dyspnea. Atypical manifestations such as gastrointestinal symptoms may occur, particularly in elderly patients with multiple comorbidities that can potentially skew and delay diagnosis. We report the case of a 79-year-old woman with a history of multiple myeloma and myasthenia gravis who presented with acute-onset abdominal pain with nausea and vomiting. Computed tomography (CT) of the abdomen and pelvis was obtained to evaluate suspected intra-abdominal pathology that incidentally detected pulmonary arterial filling defects in the right lower lobe of the lung. Subsequent CT pulmonary angiography confirmed extensive bilateral pulmonary emboli. The patient was urgently transferred to a tertiary care center for mechanical pulmonary thrombectomy with successful hemodynamic stabilization. This case highlights an atypical presentation of life-threatening PE that presented predominantly with gastrointestinal symptoms and was incidentally identified on abdominal imaging. Clinicians should maintain a high index of suspicion for PE in patients with unexplained gastrointestinal complaints, particularly in the setting of comorbidities such as malignancy and autoimmune disease that may mimic symptoms.

Flexible bronchoscopy is routinely utilized to monitor allograft function after lung transplantation (LT). While transbronchial lung biopsy (TBLB) is valuable as it permits direct histological assessment of the allograft, unexpected findings are occasionally encountered. We report a 72-year-old male with advanced chronic obstructive pulmonary disease who underwent a right single LT. His early posttransplant course was uneventful, and he presented for 6-week surveillance bronchoscopy. Although TBLB of the right lower lobe showed no evidence of rejection, one section revealed a small blood vessel with an organized intravascular thrombus. This prompted hospital admission, and an acute segmental pulmonary embolus was confirmed. Further workup identified acute deep vein thrombosis of the right soleal vein, likely the source of the embolism. The patient was treated with standard anticoagulation and discharged without complications. He was doing well at the 3-month follow-up. This case highlights the high incidence of venous thromboembolism among LT recipients and the unique challenges specific to this population. We emphasize the importance of following through on unexpected findings on TBLB, which may facilitate the timely diagnosis of posttransplant complications.