Pathological Features of COVID-19 Pneumonia Diagnosed Following an Autopsy / 대한법의학회지

After initial emergence at the end of 2019, coronavirus disease 19 (COVID-19) rapidly spread to become a pandemic. The causative agent is recognized as a novel coronavirus, named as severe acute respiratory syndrome coronavirus 2, which is known to primarily affect the respiratory system. We present the case of a 60-year-old man who was diagnosed to have COVID-19 pneumonia following an autopsy. Microscopic examination of the lung tissue showed acute (exudative) phase of diffuse alveolar damage, inflammatory infiltrates in alveolar spaces and interstitium, atypical pneumocytes with prominent nucleoli and expanded cytoplasm, and thrombi in small arterioles. Some megakaryocytes were observed, which were positive for immunohistochemical stain for CD61. The pathological findings observed in this case were consistent with those of previously published reports of COVID-19 pneumonia. This is the first case of COVID-19 pneumonia diagnosed with an autopsy in Korea.

Neonatal Sudden Death Due to Histiocytoid Cardiomyopathy / 대한법의학회지

Histiocytoid cardiomyopathy, an extremely rare heart disease in infants and children, usually occurring in girls under the age of 2 years, is characterized by cardiomegaly, ventricular arrhythmia, and sudden death. In the present study, we report a case of a 2-day-old female neonate who suddenly showed cyanosis and cardiac arrest in the neonatal unit and died without resuscitation. Autopsy revealed multifocal nodular lesions in the left ventricle wall and papillary muscles. Microscopically, these lesions were composed of discohesive round or polygonal cells with eosinophilic cytoplasm and were positive for desmin and negative for CD68. Electron microscopy findings displayed abnormal swollen mitochondria with disorganized cristae, dense granules, and diminished myofibrils in the periphery of the cytoplasm.

A Case Report of a Patient with Pleuropulmonary Blastoma Presenting as Congenital Cystic Adenomatoid Malformation / 소아알레르기및호흡기학회지

Congenital cystic adenomatoid malformation(CCAM) is one of the most common congenital lung lesions. Clinical manifestations that show are neonatal respiratory distress, recurrent respiratory infection, pneumothorax, and hemothorax. But, there are patients who are asymptomatic until mid-childhood. The treatment of asymptomatic CCAM is controversial. There is a possibility to resolve it spontaneously, but late complications such as recurrent pulmonary infection, pneumothorax, hemothorax, and cancer, which includes bronchoalveolar carcinoma and rhabdomyocarcinoma, pleuropulmonary blastoma still remain. Some investigators advocate routine surgery for all cases of CCAM that are apparent at birth. A previously healthy 16-months-old girl who had suffered from a cough for 2 weeks was transferred to Asan Medical Center with CCAM. Due to a chest CT and fever, we first thought that she had CCAM with infection. After we treated her with antibiotics for one week, we performed surgery to confirm the diagnosis and to prevent further complication. But by surgical wedge resection, a pleuropulmonary blastoma was found. There were no evidence of metastasis and adjacent involvement. She started her chemotherapy with vincristine, actinomycin D and cyclophosphamide, and is now continuing maintenance chemotherapy with etoposide, vincristine, and Ifosfamide. We report pleuropulmonary blastoma that presented as CCAM. So we recommend surgical resection in asymptomatic CCAM to confirm the diagnosis and to prevent its malignant transformation, even not accompanied by symptoms.

A Case of Combined Hepatocellular and Cholangiocarcinoma with Neuroendocrine Differentiation and Sarcomatoid Transformation: A Case Report

We report here on a case of combined hepatocellular and cholangiocarcinoma (CHC) with neuroendocrine differentiation and sarcomatoid transformation. A 59-year-old male who had had HBV-associated chronic liver disease presented with hepatic masses. The explanted liver showed three small masses, two in the right lobe and one in the left lobe. The largest one in the right lobe was a 2.0 cm sized binodular mass,consisting of a yellowish tan nodule and an abutting reddish brown nodule. Microscopically, the reddish brown nodule was a cholangiocarcinoma (CC) showing neuroendocrine differentiation and sarcomatoid tranformation. The yellowish tan nodule and the remaining two masses were hepatocellular carcinoma (HCC)s. On immunohistochemistry, both the adenocarcinoma and spindle sarcomatoid cells were positive for pancytokeratin, but only the adenocarcinoma cells were positive for chromogranin and carcinoembryonic antigen (CEA). Mitotic and Ki67 labeling indices as well as p53 immunopositivity were significantly increased only in the CC component. We report here on the first case of CHC in which the CC displayed neuroendocrine differentiation and sarcomatoid transformation with high mitotic and Ki67-labeling indices, as well as having p53 overexpression.

Two cases of localized muscle involement by polyarteritis nodosa / 대한내과학회지

Polyarteritis nodosa (PAN) is a multi systemic disease, occasionally described as limited forms of the disease. Localized form of PAN is usually associated with better prognosis. We describe unusual two cases of patients who has suffered from sudden onset of low extremity pain by localized forms of polyarteritis nodosa. Magnetic resonance imaging of the lower legs showed abnormal signal intensity of the suspected muscle. Acute necrotizing arteritis with myopathy has been revealed by muscle biopsy. The symptom of the patient has been improved soon after corticosteroid administration. Muscle biopsy of symptomatic muscles or MRI-directed biopsies can be useful to diagnose this case as PAN with localized myopathies.

Primary Primitive Neuroectodermal Tumor of the Kidney: Report of Two Cases

Primitive neuroectodermal tumor (PNET) is a small round cell neoplasm that mainly develops in the central nervous system and soft tissue of children. Primary occurrence in the kidney is rare and the identification of immunopositivity for CD99 and t(11;22)(q24;q12) is essential in differential diagnoses. We report two cases of PNET developed in a 21-year-old woman and a 44-year-old man. Resected tumors were composed of sheets of round or ovoid cells with hyperchromatic nuclei and minimal eosinophilic cytoplasm. Rosette formations, more prominent in the first case, were observed. The tumor cells of both cases were diffusely positive for CD99, vimentin, and neuron specific enolase, while they were negative for cytokeratin, desmin, and chromogranin. Synaptophysin was focally expressed only in the first case. The EWS-FLI1 chimeric gene was identified by a reverse transcriptase-polymerase chain reaction in the first case. The first patient is alive with a recurrent tumor two years after the diagnosis, and has received combination chemotherapy. The second patient is alive with no evidence of recurrence or metastasis nineteen months after the diagnosis.

Pleomorphic Liposarcoma of the Kidney: A Case Report

Although the liposarcoma is a common malignant mesenchymal tumor of the retroperitoneum, its occurrence in the kidney is very rare. A few cases involving only the renal parenchyma have been reported. The histologic features of these cases are not different from those of other body sites. We report a case of pleomorphic liposarcoma arising in the kidney of a 36-year-old man. He had been suffering from pain in the right flank for two weeks. A computed tomographic scan demonstrated a large mass in the right kidney. He underwent a radical nephrectomy under the clinical impression of renal cell carcinoma. There was a 11 cm-sized well demarcated solid mass in the lower pole of the right kidney. Microscopically, the tumor consisted of pleomorphic spindle and epithelioid cells with focal areas showing distinct adipocytic differentiation and geographic necrosis. A few diagnostic lipoblasts were present. Despite extensive search on samples, no carcinomatous component was found. Immunohistochemically, all of the tumor cells were negative for cytokeratin but positive for vimentin. Lipoblasts were positive for S-100 protein as well as for vimentin. When the kidney tumor is exclusively sarcomatous, a generous sampling with proper immunohistochemical staining is recommended to differentiate a primary sarcoma of the kidney from a sarcomatoid carcinoma.

Biliary Papillomatosis / 대한간학회지

No abstract available.