Rhinoscleroma is a chronic, granulomatous infectious lesion most frequently affecting the respiratory tract mucosa. This disease is endemic to Africa, Central and South America, South Central and Eastern Europe, the Middle East, and China. We report an extremely rare disease of nasal rhinoscleroma in Korea. The patient was a 63-yr-old man, who suffered from chronic nasal obstruction and septal deviation. Characteristic histology from a nasal biopsy was proven and special stains for bacteria were employed: periodic acid-Schiff, Warthin-Starry silver, Giemsa, and Gram stains. Isolation of Klebsiella rhinoscleromatis from a culture of nasal discharge was failed, but ultrastructural examination of numerous phagocyzed bacilli in the Mikulicz cells confirmed the diagnosis. The histiocytic nature of the Mikulicz cells was confirmed, using CD 68 and alpha-1 antitrypsin, and by the ultrastructural features of Mikulicz cells. Here, we emphasize the recognition of this rare entity in nonendemic regions, frequently leading to delayed diagnosis.
Endemic Diseases ; Fibrosis ; Human ; Klebsiella pneumoniae/*isolation & purification ; Korea ; Male ; Microscopy, Electron ; Middle Aged ; Nasal Mucosa/*microbiology/pathology/ultrastructure ; Rhinoscleroma/*pathology

Pulmonary cystic and cavitary lesions caused by diverse etiologies are commonly encountered in chest imaging. The terms "cyst" and "cavity" are used to describe air-filled regions in the center of a nodule or consolidation of the lung. To date, only radiologic aspects of these lesions have been addressed. The morphologies of pulmonary cystic and cavitary lesions exhibit a broad spectrum, ranging from benign to malignant pulmonary diseases of acquired or congenital origin, including variable infectious diseases. In this review, we summarized the differential diagnosis of pathological entities to provide pathologists and radiologists with an overview of the diseases most commonly associated with pulmonary cystic and cavitary lesions in adults and children. The results showed slightly different patterns in the distribution of the diseases in the two groups. The most common causes of cavitary lesions include malignancy and infection in adults, and congenital malformation in children. Therefore, identification of pathologic entities correlating with the radiologic findings, clinical course, and location of the lesion is important in the evaluation of cystic and cavitary lung lesions in order to avoid unnecessary surgical procedures or delayed treatment.
Adult ; Child ; Communicable Diseases ; Diagnosis, Differential ; Humans ; Lung ; Lung Diseases ; Thorax

We herein report a case of intractable epilepsy that occurred in a 7-year-old girl, which is consistent with radiological and clinicopathological hallmarks of Rasmussen's encephalitis. The patient showed characteristic primary unilateral involvement with secondary bilateral propagation. Microscopically, the cortical atrophy due to neuronal loss, intense GFAP-immunoreactive astrogliosis, neuronophagia, perivascular lymphocytic infiltration and microglial nodules was seen throughout the cortex and white matter. No viral inclusions were noted; no cytomegalovirus, herpes simplex virus or Epstein-Barr virus was found by in situ hybridization. Granular immunofluorescence for C4, C1q and IgG within the blood vessel walls was noted, and ultrastructurally, only nonspecific vascular injury was found. Rasmussen's encephalitis is a diagnosis of exclusion; it can be diagnosed by the combination of clinical manifestation, neuroimaging and characteristic pathologic features.
Atrophy ; Blood Vessels ; Child ; Cytomegalovirus ; Diagnosis ; Encephalitis* ; Epilepsy ; Female ; Fluorescent Antibody Technique ; Herpesvirus 4, Human ; Humans ; Immunoglobulin G ; Immunohistochemistry ; In Situ Hybridization ; Microscopy, Electron ; Neuroimaging ; Neurons ; Simplexvirus ; Vascular System Injuries

BACKGROUND: Pulmonary vessel sarcomas are rare, and their pathogenesis is still unclear. METHODS: We focus on the pathologic findings of fourteen pulmonary artery and/or vein sarcomas along with clinical prognosis. RESULTS: Nine patients were male and five were female, and they ranged in age from 26 to 72 years (mean, 47 years). There were ten cases of pulmonary artery sarcoma, three cases of pulmonary artery and vein sarcoma, and one case of pure pulmonary vein sarcoma. Ten out of the fourteen cases were associated with pulmonary thromboembolism. Microscopically, all the tumors showed an undifferentiated sarcomatous portion. There were leiomyosarcoma portions in 8 cases, malignant fibrous histiocytomatous portions in 7 cases, angiosarcomatous differentiation in 3 cases, and osteosarcomatous portion in 1 case. All but two patients died during the follow up period (range, 1 to 78 months). The mean survival time of the patients who died was 14 months and the longest survival time was 78 months after surgical resection. CONCLUSIONS: The current study is one of the largest single institutional reviews of pulmonary artery and/or vein sarcoma. Regardless of the histological components and macroscopic growth patterns, these rare tumors have a grave prognosis.
Female ; Follow-Up Studies ; Glycosaminoglycans ; Humans ; Leiomyosarcoma ; Male ; Prognosis ; Pulmonary Artery ; Pulmonary Embolism ; Pulmonary Veins ; Sarcoma ; Survival Rate ; Veins

Scrotal leiomyomas with atypical bizarre nuclei are rare, which might be misdiagnosed as malignant tumor. We describe a case of scrotal bizarre leiomyoma in a 65-yr-old man. The tumor was a 1 cm-sized, well circumscribed, oval mass arising from the tunica dartos muscle. Histologically, it was formed by whorling bundles of fusiform cells with occasional atypical, pleomorphic nuclei and pseudoinclusions. Mitosis was not found. Although morphologically atypical, scrotal bizarre leiomyomas take on a biologic behavior not different from that of conventional leiomyoma, they should be distinguished from leiomyosarcoma to avoid unnecessary treatment.
Aged ; Genital Neoplasms, Male/*pathology/surgery ; Human ; Leiomyoma/*pathology/surgery ; Male ; Scrotum/*pathology

Granular cell tumor (GCT) is a slow-growing benign neoplasm that can be found in any organ. Pediatric laryngotracheal GCT is rare. We experienced a 6-year-old boy suffering from a barking cough and symptoms of stridor and croup for one month. Head and neck computed tomography revealed a protruding mass that occluded 60% of the airway lumen. Under the impression of hemangioma or papilloma, excision revealed a submucosal non-encapsulated mass. Histologically, the mass was composed of sheets of large polyhedralshaped tumor cells containing plump eosinophilic granular cytoplasm and centrally placed, small, bland-appearing nuclei. The tumor cells were positive for S-100 protein, and voluminous eosinophilic cytoplasm was stained by diastase-resistant periodic acid-Schiff. The present report describes a unique case of a huge pediatric laryngeal GCT extending to the subglottic trachea. We also review the clinical course of pediatric laryngotracheal GCT and emphasize the importance of diagnosing GCT in children.

A 39-year-old man visited the department of otolaryngology due to an ongoing hearing disturbance that had lasted for 1 year. Temporal bone computed tomography revealed soft tissue density nearly obliterating the left external auditory canal (EAC). The mass was composed of sheets of round tumor cells containing moderate amounts of fine granular cytoplasm and salt and pepper chromatin. Neither mitosis nor necrosis was found. The Ki-67 proliferation index was less than 2%. Cells were positive for CD56 and synaptophysin but negative for chromogranin, cytokeratin (CK) 20, and CK7. Based on these findings, the tumor was diagnosed as a carcinoid tumor, well differentiated neuroendocrine carcinoma, grade 1 (G1) according to current World Health Organization (WHO) classification of head and neck tumors; and a neuroendocrine tumor, G1 according to neuroendocrine neoplasm (NEN)-2018 WHO standard classification. He remained free of local recurrence and metastasis after 20 months of follow up. To date, only six cases of primary NENs in the EAC have been reported. Metastatic tumor should be included in the differential diagnoses. Because of its rarity, the prognosis and treatment have not yet been clarified.

The innate immune system confers first-line defense against various pathogens including bacteria and viruses. Early detection of invading pathogens by the host depends on a limited number of specific pattern recognition receptors (PRRs) that detect pathogen associated molecular patterns (PAMPs) and activate signal transduction cascades that lead to activation of defense mechanisms. Among those sensors, RIG-I-like receptors (RLRs) play crucial roles in the detection of viruses by recognizing intracellular viral patterns such as viral RNAs to induce type-I interferon production. The discovery of intracellular RNA sensing mechanism by RIG-I prompted the investigations to find out intracellular DNA sensors. Recently, several proteins including DAI, AIM2, IFI16, and cGAS have been suggested as DNA sensing molecules to detect DNA viruses and bacteria, suggesting there are multiple receptors for microbial DNA. In this review, we discuss the current our understanding of sensing microbial DNA and subsequent induction of immune responses.
Bacteria ; Defense Mechanisms ; DNA ; DNA Viruses ; Immune System ; Immunity, Innate ; Interferons ; Proteins ; Receptors, Pattern Recognition ; RNA ; RNA, Viral ; Signal Transduction

Metastatic calcification is rare; it is found during autopsy in patients who underwent hemodialysis. Diffuse calcium precipitation of small and medium-sized cutaneous vessels, known as calciphylaxis, can result in progressive tissue necrosis secondary to vascular calcification. This condition most commonly involves the skin; however, a rare occurrence of visceral calciphylaxis has been reported. Here we report on an autopsy case. Despite a thorough evaluation, and even performing an autopsy, the underlying cause of acute-onset hypercalcemia, resulting in the production of pulmonary calciphylaxis and metastatic renal calcification associated with acute respiratory and renal failure, could not be determined. Metastatic calcification often lacks specific symptoms, and the degree of calcification is a marker of the severity and chronicity of the disease. This unusual autopsy case emphasizes the importance of rapidly progressing visceral calciphylaxis, as well as its early detection.
Autopsy ; Calciphylaxis ; Calcium ; Humans ; Hypercalcemia ; Necrosis ; Renal Dialysis ; Renal Insufficiency ; Vascular Calcification

Strongyloides stercoralis hyperinfection in immunocompromised patients is difficult to control due to delayed diagnosis, especially in nonendemic areas. A 70-year-old diabetic woman came in with an intermittent diarrhea. She received massive steroid therapy for a week under the impression of idiopathic gastrointestinal eosinophilic syndrome. Diagnosis of strongyloidiasis was made by demonstration of filariform larvae in two repeated sputum specimens two months later. Despite massive administration of albendazole, she died of diabetic ketoacidosis and septic shock. Autopsy revealed a diffusely thickened bowel wall, superimposed invasive pulmonary aspergillosis and the near total destruction of the lungs. Filariform larvae were detected only in the cutaneous lesions. It was presumed that Strongyloides stercoralis hyperinfection was caused by autoinfection in the patient's immunosuppressed status. The present case has two clinical importances; first, intensive treatment with albendazole could erradicate parasites except for the skin but sepsis presumably occurred due to a hypersensitivity reaction against liberated endotoxins during the death of the parasites by the drug. Second, cutaneous parasitic lesion resists the intensive antihelminthic treatment in an immunocompromised host.
Aged ; Albendazole ; Autopsy* ; Delayed Diagnosis ; Diabetic Ketoacidosis ; Diagnosis ; Diarrhea ; Endotoxins ; Eosinophils ; Female ; Humans ; Hypersensitivity ; Immunocompromised Host ; Invasive Pulmonary Aspergillosis ; Larva* ; Lung ; Parasites ; Sepsis ; Shock, Septic ; Skin ; Sputum ; Strongyloides stercoralis ; Strongyloidiasis*