Inflammation and vascular remodeling in COVID-19 hearts

A wide range of cardiac symptoms have been observed in COVID-19 patients, often significantly influencing the clinical outcome. While the pathophysiology of pulmonary COVID-19 manifestation has been substantially unraveled, the underlying pathomechanisms of cardiac involvement in COVID-19 are largely unknown. In this multicentre study, we performed a comprehensive analysis of heart samples from 24 autopsies with confirmed SARS-CoV-2 infection and compared them to samples of age-matched Influenza H1N1 A (n = 16), lymphocytic non-influenza myocarditis cases (n = 8), and non-inflamed heart tissue (n = 9). We employed conventional histopathology, multiplexed immunohistochemistry (MPX), microvascular corrosion casting, scanning electron microscopy, X-ray phase-contrast tomography using synchrotron radiation, and direct multiplexed measurements of gene expression, to assess morphological and molecular changes holistically. Based on histopathology, none of the COVID-19 samples fulfilled the established diagnostic criteria of viral myocarditis. However, quantification via MPX showed a significant increase in perivascular CD11b/TIE2 + -macrophages in COVID-19 over time, which was not observed in influenza or non-SARS-CoV-2 viral myocarditis patients. Ultrastructurally, a significant increase in intussusceptive angiogenesis as well as multifocal thrombi, inapparent in conventional morphological analysis, could be demonstrated. In line with this, on a molecular level, COVID-19 hearts displayed a distinct expression pattern of genes primarily coding for factors involved in angiogenesis and epithelial-mesenchymal transition (EMT), changes not seen in any of the other patient groups. We conclude that cardiac involvement in COVID-19 is an angiocentric macrophage-driven inflammatory process, distinct from classical anti-viral inflammatory responses, and substantially underappreciated by conventional histopathologic analysis. For the first time, we have observed intussusceptive angiogenesis in cardiac tissue, which we previously identified as the linchpin of vascular remodeling in COVID-19 pneumonia, as a pathognomic sign in affected hearts. Moreover, we identified CD11b + /TIE2 + macrophages as the drivers of intussusceptive angiogenesis and set forward a putative model for the molecular regulation of vascular alterations.

A Morphomolecular Approach to Alveolar Capillary Dysplasia

Alveolar capillary dysplasia (ACD) is a rare lung developmental disorder leading to persistent pulmonary arterial hypertension and fatal outcomes in newborns. The current study analyzed the microvascular morphology and the underlying molecular background of ACD. One ACD group (n = 7), one pulmonary arterial hypertension group (n = 20), and one healthy con1trol group (n = 16) were generated. Samples of histologically confirmed ACD were examined by exome sequencing and array-based comparative genomic hybridization. Vascular morphology was analyzed using scanning electron microscopy of microvascular corrosion casts. Gene expression and biological pathways were analyzed using two panels on inflammation/kinase-specific genes and a comparison analysis tool. Compartment-specific protein expression was analyzed using immunostaining. In ACD, there was an altered capillary network, a high prevalence of intussusceptive angiogenesis, and increased activity of C-X-C motif chemokine receptor 4 (CXCR4), hypoxia-inducible factor 1α (HIF1A), and angiopoietin signaling pathways compared with pulmonary arterial hypertension/healthy controls. Histologically, there was a markedly increased prevalence of endothelial tyrosine kinase receptor (TEK/TIE2)⁺ macrophages in ACD, compared with the other groups, whereas the CXCR4 ligand CXCL12 and HIF1A showed high expression in all groups. ACD is characterized by dysfunctional capillaries and a high prevalence of intussusceptive angiogenesis. The results indicate that endothelial CXCR4, HIF1A, and angiopoietin signaling as well as TIE2⁺ macrophages are crucial for the induction of intussusceptive angiogenesis and vascular remodeling. Future studies should address the use of anti-angiogenic agents in ACD, where TIE2 appears as a promising target.

The Challenge of Long-Term Cultivation of Human Precision-Cut Lung Slices

Human precision-cut lung slices (PCLS) have proven to be an invaluable tool for numerous toxicologic, pharmacologic, and immunologic studies. Although a cultivation period of <1 week is sufficient for most studies, modeling of complex disease mechanisms and investigating effects of long-term exposure to certain substances require cultivation periods that are much longer. So far, data regarding tissue integrity of long-term cultivated PCLS are incomplete. More than 1500 human PCLS from 16 different donors were cultivated under standardized, serum-free conditions for up to 28 days and the viability, tissue integrity, and the transcriptome was assessed in great detail. Even though viability of PCLS was well preserved during long-term cultivation, a continuous loss of cells was observed. Although the bronchial epithelium was well preserved throughout cultivation, the alveolar integrity was preserved for about 2 weeks, and the vasculatory system experienced significant loss of integrity within the first week. Furthermore, ciliary beat in the small airways gradually decreased after 1 week. Interestingly, keratinizing squamous metaplasia of the alveolar epithelium with significantly increasing manifestation were found over time. Transcriptome analysis revealed a significantly increased immune response and significantly decreased metabolic activity within the first 24 hours after PCLS generation. Overall, this study provides a comprehensive overview of histomorphologic and pathologic changes during long-term cultivation of PCLS.

Morphomolecular motifs of pulmonary neoangiogenesis in interstitial lung diseases

The pathogenetic role of angiogenesis in interstitial lung diseases (ILDs) is controversial. This study represents the first investigation of the spatial complexity and molecular motifs of microvascular architecture in important subsets of human ILD. The aim of our study was to identify specific variants of neoangiogenesis in three common pulmonary injury patterns in human ILD.We performed comprehensive and compartment-specific analysis of 24 human lung explants with usual intersitial pneumonia (UIP), nonspecific interstitial pneumonia (NSIP) and alveolar fibroelastosis (AFE) using histopathology, microvascular corrosion casting, micro-comupted tomography based volumetry and gene expression analysis using Nanostring as well as immunohistochemistry to assess remodelling-associated angiogenesis.Morphometrical assessment of vessel diameters and intervascular distances showed significant differences in neoangiogenesis in characteristically remodelled areas of UIP, NSIP and AFE lungs. Likewise, gene expression analysis revealed distinct and specific angiogenic profiles in UIP, NSIP and AFE lungs.Whereas UIP lungs showed a higher density of upstream vascularity and lower density in perifocal blood vessels, NSIP and AFE lungs revealed densely packed alveolar septal blood vessels. Vascular remodelling in NSIP and AFE is characterised by a prominent intussusceptive neoangiogenesis, in contrast to UIP, in which sprouting of new vessels into the fibrotic areas is characteristic. The molecular analyses of the gene expression provide a foundation for understanding these fundamental differences between AFE and UIP and give insight into the cellular functions involved.

Immunogenic cell death of dendritic cells following modified vaccinia virus Ankara infection enhances CD8+ T cell proliferation

"Immunogenic cell death" (ICD) is associated with the emission of so-called damage-associated molecular patterns (DAMPs) which trigger the immune response against dead-cell associated antigens. The secretion of the DAMP, adenosine triphosphate (ATP) has been shown to be autophagy-dependent. Here, we demonstrate that Modified Vaccinia virus Ankara (MVA), a highly attenuated strain of vaccinia virus, induces both cell death and autophagy in murine bone marrow-derived dendritic cells (BMDCs), which in turn confer the (cross-)priming of OVA-specific cytotoxic T cells (OT-I cells). Additionally, we show that MVA infection leads to increased extracellular ATP (eATP) as well as intracellular ATP (iATP) levels, with the latter being influenced by the autophagy. Furthermore, we show that the increased eATP supports the proliferation of OT-I cells and inhibition of the P2RX7 receptors results in an abrogation of the proliferation. These data reveal novel mechanisms on how MVA enhances adaptive immunity in vaccine strategies.

Cardiorenal Syndrome: Clinical Outcome Study

BACKGROUND

Over recent years, the field of medicine has been challenged by the twin epidemic of heart failure and renal insufficiency. The coexistence of the two problems in the same patient, referred to as cardiorenal syndrome (CRS), is defined as 'disorders of the heart and kidneys whereby acute or chronic dysfunction in one organ may induce acute or chronic dysfunction of the other. The mechanisms underlying this interaction are complex and multifactorial in nature.

OBJECTIVE OF STUDY

Identify and classify patients admitted with cardiorenal syndrome into various subtypes and assess clinical outcome at discharge and at three months.

METHODS

Ours was a longitudinal study of 50 patients admitted in ICU with CRS. They were classified as per RONCO classification (2008) into various subtypes. Outcomes was addressed as favourable for patients stable at discharge and at 3 months follow up, whereas outcome was termed non-favourable for patients who expired or initiated on hemodialysis.

RESULTS

Of 50 patients, two-third patients were males (66%), with mean age of males and females being 64.18 years and 64.64 years respectively. Majority of the patients had Type-1 CRS (46%) followed by twenty two percent Type-2, twenty six percent type-4 and six percent Type-5. There were no patients with type-3 CRS. At the end of the study, 24 (48%) patients were stable, 12 (24%) required dialysis and 14 (28%) patients had expired. The total non-favourable outcomes (dialysis / death) were higher with subtypes CRS-4 (n-11, 22%) and CRS-1 (n-8, 16%). Anemia, raised serum creatinine, low eGFR values, low ejection fraction were significant predictors of non-favourable outcome in our study.

CONCLUSIONS

CRS occurs in all age groups, more commonly in elderlies with a male preponderance. Prevalence of CRS-1 was higher followed by CRS-4. Prognosis was unfavourable in CRS-1, CRS-4 and CRS-5. Sepsis was predominant cause of death in patients with CRS-5 with hundred percent mortality during hospital stay. Risk factors like pre-existing renal impairment, anemia, reduced e GFR and low ejection fraction were significantly associated with worse outcomes. There is need for large scale population / community based studies to chart the prevalence of cardiorenal subtypes and prognosticate each individually.

Stressful life events, hopelessness, and suicidal intent in patients admitted with attempted suicide in a tertiary care general hospital

BACKGROUND

Suicide is a psychiatric emergency. Stressors in life and social variables (like marital status, family, and social support) are among the determinants of suicide. Hopelessness and suicidal intent are among the psychological variables that have shown promise in the prediction of suicide.

AIMS AND OBJECTIVES

To assess stressful life events, hopelessness, suicidal intent, and sociodemographic variables in patients of attempted suicide.

MATERIALS AND METHODS

Fifty consecutive patients admitted with attempted suicide were interviewed. Presumptive Stressful Life Event Scale, Beck Hopelessness Scale, and Beck Suicidal Intent Scale were used along with a semistructured pro forma for interview. Data were analyzed with statistical tests.

RESULTS

Sixty-six percent of the participants were females, 72% were less than 30 years of age. Sixty-six percent of the patients had stressful life event score between 101 and 200 with the mean score of 127. The stressful life event score in those who considered they are in need of psychiatric help was significantly high. Most of the patients had mild (34%) and moderate (40%) degrees of hopelessness, and the mean score was 9.64. The mean suicidal intent in the participants was 25.14, when correlated with hopelessness score significant positive correlation was found.

CONCLUSION

Lethality of the attempt increases with the increase in hopelessness.

Sudden onset abdominal pain and distension: an imaging sparkler

We present a case of a middle-aged patient presenting with acute onset abdominal pain and distension who had signs of bowel obstruction on physical exam. He was afebrile, hemodynamically stable with no peritoneal signs. Abdominal radiograph and CT scan were pathognomic for sigmoid volvulus. Through this case report we want to discuss the presentation, diagnosis, management options for sigmoid volvulus and importance of features suggestive of ischemic bowel that necessitates different management options.

Beta-lapachone inhibits proliferation and induces apoptosis in retinoblastoma cell lines

AIMS

To investigate the cytotoxicity of beta-lapachone, a potent agent that may selectively target tumour cells, in retinoblastoma (RB) cell lines.

METHODS

Growth inhibitory effects of beta-lapachone were evaluated in Y79, WERI-RB1, and RBM human retinoblastoma cell lines. Pro-apoptotic effects of beta-lapachone were evaluated in Y79 cells by detection of caspase 3/7 activity, by enzyme-linked immunosorbent assay for nucleosome fragments, and by cellular morphological analysis.

RESULTS

Beta-lapachone induced significant dose-dependent growth inhibitory effects in all three retinoblastoma cell lines. The 50% growth inhibitory concentration (IC(50)) of this agent was 1.9 microM in Y79 cells, 1.3 microM in WERI-RB1 cells, and 0.9 microM in RBM cells. Beta-lapachone also induced proapoptotic effects in RB cells. Treatment of Y79 cells with 1.9 microM beta-lapachone (IC(50)) resulted in a peak, fourfold induction of caspase 3/7 activity at 72 h post-treatment; a peak, 5.6-fold increase in nucleosome fragments at 96 h post-treatment; and a peak, 1.7-fold increase in the frequency of apoptotic cells at 48 h post-treatment, relative to vehicle-treated controls.

CONCLUSION

Beta-lapachone induced potent cytotoxic effects in RB cell lines at low micromolar concentrations, suggesting this agent could be useful in the clinical management of RB.

Effects of celecoxib in human retinoblastoma cell lines and in a transgenic murine model of retinoblastoma

BACKGROUND/AIM

Celecoxib, a cyclooxygenase-2 inhibitor and antiangiogenic agent, has demonstrated potent anticancer effects in preclinical studies and in human clinical trials. To evaluate the potential utility of this agent in the treatment of retinoblastoma, the authors investigated the effects of celecoxib in retinoblastoma cell lines and in a murine model of this disease.

METHODS

Growth inhibitory effects of celecoxib were evaluated in Y79 and Weri-RB1 human retinoblastoma cell lines by WST-1 cell proliferation assay. For animal study, two groups of 24, 8 week old LHbeta-TAg transgenic mice were treated with celecoxib (250 mg/kg, orally once a day) or vehicle control, 5 days/week for 6 weeks. Mice were sacrificed on day 43. Enucleated eyes were serially sectioned and ocular tumour burden was quantified by histopathological analysis.

RESULTS

Celecoxib did not inhibit proliferation of Y79 or Weri-RB1 cells, even at concentrations far exceeding clinically achievable levels. No significant difference in ocular tumour burden between celecoxib treated and control mice (p=0.73) was found.

CONCLUSION

Celecoxib was ineffective at inhibiting proliferation of retinoblastoma cells in vitro and was ineffective at controlling retinoblastoma tumour growth in a murine model of this disease. On the basis of these findings, oral celecoxib therapy is unlikely to have clinical utility in the treatment of retinoblastoma.

Composite cardiac binding in experimental heart failure

BACKGROUND

Composite cardiac binding consists of wrapping the heart with a synthetic membrane and a pericardial interposition. The goal of the present study was to apply composite cardiac binding to a canine model of heart failure.

METHODS

Twenty dogs were randomized to 2 groups: untreated heart failure (group 1, n = 13) and heart failure pretreated by composite cardiac binding (group 2, n = 7). They received a total dose of 1 mg x kg(-1) of intracoronary doxorubicin over 4 weeks. Hemodynamic data were obtained at weeks 0, 7, and 12. All animals were followed up with weekly echocardiography for 12 weeks.

RESULTS

Survival in group 1 was 54% and in group 2 was 100% at week 12 (p = 0.0438). Left ventricular end-diastolic pressure increased by 153% in group 1 and by 59% in group 2 (p = 0.0395) at week 12. Ejection fraction decreased by 27% in group 1 and by 19% in group 2 (p = 0.4401) at week 12.

CONCLUSIONS

Composite cardiac binding significantly prolongs survival and attenuates left ventricular dilatation and the increase in left ventricular end-diastolic pressure associated to chronic heart failure. Further evaluation in established heart failure is needed. Composite cardiac binding may be used for the prevention of recurrent dilatation following reduction ventriculoplasty.

Lymphomatoid granulomatosis following autologous stem cell transplantation

Lymphomatoid granulomatosis (LYG) is a rare angio-destructive lymphoproliferative disorder (LPD) of uncertain etiology, with prominent pulmonary involvement. Recent studies indicate that LYG is an Epstein-Barr virus (EBV)-associated B cell LPD with large numbers of background reactive T lymphocytes (T cell-rich B cell lymphoma). Although the disease frequently, but not exclusively, occurs in various immunodeficiency states, it has not been reported in association with the transient immunosuppression following autologous bone marrow/peripheral stem cell transplantation (ABM/PSCT). We describe a patient who developed lymphomatoid granulomatosis of the lung approximately 2 weeks after high-dose chemotherapy and autologous peripheral stem cell transplantation for multiple myeloma. Although molecular studies showed no evidence of EBV genome in the biopsy material, the serologic profile with high IgM titers was suggestive of primary EBV infection. Complete radiologic remission occurred following reconstitution of the patient's immune response after a 2-week course of ganciclovir treatment. Despite the apparently low frequency of LPD (both LYG and EBV-associated post-transplant lymphoma) in the ABMT setting, we believe that it should be considered in the differential diagnosis of patients whose clinical course following ABMT is complicated by fevers, in the absence of an identifiable infectious process.

Vertebral blastomycosis with paravertebral abscess: report of eight cases and review of the literature

Bone is the third most frequent site of disease in patients with blastomycosis, and the vertebrae are among the bones affected most often. We describe the clinical features and treatment of eight patients with vertebral blastomycosis and review the literature regarding this disease. All eight patients had destructive vertebral lesions evident on radiographs, and all had clinical or radiographic evidence of a contiguous abscess. The lower thoracic or lumbar regions were affected most often. Fever and skin lesions typical of blastomycosis were variably present. All but one patient had an abnormal chest radiograph. Treatment included long-term antifungal therapy and drainage of large fluid collections. Five of the eight patients were cured of their disease. Of the other 3 patients, 1 is still receiving therapy and is probably cured, 1 died of blastomycosis, and the status of 1 is unknown. In areas of endemicity, blastomycosis should be a diagnostic consideration for any patient with a destructive vertebral lesion.

Experimental cardiomyopathy as a model of chronic heart failure

End-stage heart disease is a major health care issue and it represents one of the most costly diseases. Several experimental heart failure models have been developed; however, a single model is not widely accepted as representative of clinical heart failure. The doxorubicin-induced cardiomyopathy model was used in the current study to address two issues: 1) to define a standardized dose regimen of intracoronary doxorubicin infusion; and 2) to establish a method of determining the onset and time course of heart failure. Twenty dogs underwent placement of an intracoronary catheter. A total dose of 1 mg/kg of intracoronary doxorubicin was infused. Hemodynamics were obtained at weeks 0, 7, and 12. Echocardiography was performed weekly. Right and left ventricular biopsy specimens were examined at weeks 0 and 12. Survival after doxorubicin-induced cardiomyopathy was 60% at week 12. The development of heart failure was demonstrated by a significant decrease in left ventricular ejection fraction and cardiac index and a significant increase in left ventricular end-diastolic pressure and volume. The leukocyte count, hemoglobin, and hematocrit decreased significantly. Histologic changes of both the right and left ventricular myocardial biopsy specimens included myocellular hypertrophy, loss of myofibrillar material, and vacuolization. Intracoronary doxorubicin reliably produced an experimental model of accelerated heart failure that developed over the course of 12 weeks. Echocardiographic monitoring allowed a close surveillance of heart failure development. This model may be useful to evaluate the efficacy of cardiomyoplasty, mechanical assist devices, transplantation, and reduction ventriculoplasty.

Cardiac binding in experimental heart failure

BACKGROUND

Cardiomyoplasty is a potential therapy for heart failure. Its benefits are attributed to systolic augmentation (dynamic cardiomyoplasty) and prevention of cardiac dilatation (static cardiomyoplasty). To evaluate the static component, we used an artificial membrane for cardiac binding in a canine model of heart failure.

METHODS

Intracoronary doxorubicin was administered weekly for 4 weeks to induce heart failure in 10 dogs, each of which was assigned to one of two treatment groups: (1) no treatment, or (2) cardiac binding. Hemodynamic data were obtained at operation and at 7 weeks after operation. Echocardiography was performed weekly.

RESULTS

Left ventricular end-diastolic pressure and diameter, and right ventricular end-diastolic diameter increased in group 1 (from 9.6 +/- 6.1 to 19.6 +/- 2.3 mm Hg, p = 0.009; from 3.9 +/- 0.4 to 5 +/- 0.3 cm, p = 0.0013; and from 1.6 +/- 0.2 to 1.9 +/- 0.3 cm, p = 0.0036, respectively). Ejection fraction fell in group 1 from 0.60 +/- 0.10 to 0.40 +/- 0.04 (p = 0.0009) and in group 2 from 0.56 +/- 0.02 to 0.40 +/- 0.04 (p = 0.0001), but the difference between groups was not significant.

CONCLUSION

Cardiac binding reduces the ventricular dilatation associated with heart failure without exacerbating left ventricular dysfunction.

Extrarenal retroperitoneal angiomyolipoma

We describe a case of angiomyolipoma arising in the retroperitoneum and review other reported cases of extrarenal angiomyolipoma. We review the histologic characteristics of angiomyolipoma and describe our diagnostic evaluation. This case is the fifth reported occurrence of extrarenal retroperitoneal angiomyolipoma. In our case, as in the others, the correct diagnosis was made only after laparotomy, despite a number of preoperative imaging studies. Careful exploration should, in the future, result in more renal-sparing approaches.

Gestational trophoblastic disease: a spectrum of radiologic diagnosis

Gestational trophoblastic disease (GTD) encompasses a broad spectrum of conditions that includes hydatidiform mole, invasive mole, and choriocarcinoma. Although ultrasound (US) is the examination of choice for initial diagnosis, plain radiography, angiography, computed tomography (CT), and magnetic resonance (MR) imaging all play a role in determining the presence of GTD and the extent of its complications. US shows molar gestations as alternating cystic and solid tissue that fills the entire uterus. CT and MR imaging are useful in detecting myometrial invasion, parametrial extension, and metastasis. Because each imaging technique offers a unique perspective highlighting different aspects of GTD, it is important to understand the pathophysiology and natural history of the disease. Such knowledge in turn leads to a greater understanding of the spectrum of findings seen on various kinds of radiologic images and enables the radiologist to play an important role in directing patient work-up by recognizing the implications of various findings and guiding management decisions.

Loose body of the elbow mimicking tumor

Distinguishing between calcific soft-tissue masses and intra-articular loose bodies about the elbow can be difficult. We present the case of a 59-year-old woman with a slowly enlarging soft-tissue mass about the elbow. History, physical examination, and diagnostic studies did not establish a definite diagnosis, nor did they rule out the possibility of a neoplastic process. Excisional biopsy revealed a loose body contained in a cystic mass with elbow joint communication.

Case report 731. Complicated Baker's cyst

The atypical appearance of a gas-containing, noninfected, popliteal synovial cyst has been presented. The case again demonstrates the value of plain radiographs, in this instance in distinguishing gas bubbles and calcification, which may not be apparent by MRI and ultrasound. The uniqueness of this case is stressed. The cause of the gas bubbles was not ascertained.

MR imaging in high-risk obstetric patients: a valuable complement to US

The accuracy of prenatal diagnosis has become increasingly critical in the field of high-risk obstetrics. Although ultrasound (US) provides adequate information in most cases and continues to be the initial prenatal examination of choice, there are instances in which the results of the US study may be equivocal. The role of magnetic resonance (MR) imaging was explored in 27 selected patients with various indications to determine its effectiveness as a complement to US. MR imaging was most helpful in the diagnosis of extrauterine gestation, evaluation of placental position, determination of extent or nature of masses associated with pregnancy, and differentiation between diaphragmatic hernia and a thoracic mass. Although MR imaging did not add information that affected the accuracy of the diagnosis of oligohydramnios, in all other cases it provided an extra dimension in diagnosis by showing clearer anatomic relationships in the pelvis. It has proved to be a valuable complement to an equivocal US study.

Magnetic resonance imaging of pulmonary artery aneurysm

Pulmonary artery aneurysm is a rare condition. We have presented what we believe to be the first case in the English literature to be diagnosed by magnetic resonance imaging.

CT diagnosis of right hemothorax secondary to ruptured thoracoabdominal aneurysm: case report

The development of a right hemothorax as the result of a ruptured thoracoabdominal aneurysm is an uncommon and usually fatal event. Survival depends upon an accurate diagnosis and prompt surgical intervention. We present a case of a ruptured thoracoabdominal aneurysm into the right chest that presented as opacification of the right hemithorax and hypotension. An early CT scan provided the correct preoperative diagnosis, although the patient did not survive.

Computed tomography and magnetic resonance imaging in the diagnosis of pulmonary thromboembolic disease

In selected cases CT and MRI may be useful for the evaluation of patients suspected of having central pulmonary emboli. In stable patients MRI appears to be superior to CT because no iodinated contrast medium is required. In evaluating critically ill patients CT is better because of its superior resolution, ability to assess changes in the lung parenchyma, and ease of patient monitoring.

Bronchogenic cysts

Bronchogenic cysts are relatively uncommon congenital lesions. They may be detected on routine radiography in asymptomatic patients or may present with various manifestations, some of which may be life-threatening. Age at diagnosis ranges from infancy to late adulthood, with asymptomatic lesions occurring more often in older children and adults. Cysts may be located in subcarinal, paratracheal, hilar, paraesophageal and intrapulmonary sites. The chest radiograph is the primary diagnostic study, with computed tomographic scans of the chest providing more definitive evaluation. Despite some controversy, surgery is considered the treatment of choice, even in the asymptomatic patient.

CT of emphysematous gastritis

Emphysematous gastritis is a serious, often fatal condition. It is the result of destruction of the mucosal membrane with subsequent bacterial invasion of the stomach. We have encountered two cases at CT. Recognition is important since early intervention may be lifesaving.

Azygos continuation of the inferior vena cava masquerading as neoplasm

The two cases we have reported demonstrate that dramatic enlargement of the azygos vein may occur in patients with azygos continuation of the inferior vena cava. Awareness of this phenomenon can prevent unnecessary procedures. The diagnosis should be established by dynamic CT scan.

Hemorrhagic adrenal metastases: CT findings

Adrenal hemorrhage secondary to metastases is uncommon. We have encountered four such cases that presented as large adrenal masses. In all cases the CT findings were of an inhomogeneous mixed-density adrenal mass with extensive perirenal changes suggestive of perirenal hemorrhage or mass. When such a lesion is seen, hemorrhagic adrenal metastases should be considered. Fluid may be of high density, suggestive of hemorrhage. However, as the adrenal is in the perinephric space, hemorrhage from any cause (trauma, metastases, or anticoagulant) in the adrenal gland will gravitate into the perinephric space.

Lingual thyroid: unusual appearance on computed tomography

A patient with a lingual thyroid was found to have inhomogeneous contrast enhancement on CT, findings not previously reported. Operative and histologic examination revealed marked thyroiditis and goitrous changes, explaining the CT findings.

Aortic dissection, a diagnostic dilemma: case report

A case of type I (type A) aortic dissection proved by postmortem examination could not be fully delineated relative to the type of dissection by dynamic CT as well as three positive contrast aortograms. Small tears in the ascending aorta and their strategic locations can escape even intensive radiologic evaluation. We present a case in which medical therapy was provided and, inappropriately, surgery was not performed.

CT findings in abdominal actinomycosis

The diagnosis of abdominal actinomycosis is difficult because of its relative infrequency and imitation of other diseases. We present four cases in which these difficulties in diagnosis were experienced and show the utility of CT in suggesting this disease. Aspiration, biopsy, and proper culture technique, in conjunction with typical CT findings of transfascial and multiple organ involvement, led to the proper diagnosis in all cases.

Hyperdense parapelvic cyst confused with renal tumor

We have reported a case of a hyperdense parapelvic renal cyst that could not be easily differentiated from a solid tumor by multiple diagnostic studies. However, the typical findings of a hyperdense parapelvic cyst may allow less aggressive surgery.

Solitary splenic abscess: a new complication of splenic salvage treated by percutaneous drainage

A patient sustained a gunshot injury to the spleen. The spleen was left intact in an attempt to maintain normal immune function in the patient. The patient developed a splenic abscess as a result of the injury, a complication of splenic salvage that we have not found reported before. The abscess was treated successfully via CT-guided percutaneous drainage.