Imaging in mediastinitis: a systematic review based on aetiology

Role of Radiology in Assessment of Postoperative Complications of Heart Transplantation

Heart transplantation is a pivotal treatment of end-stage heart failure, and recent advancements have extended median posttransplant life expectancy. However, despite the progress in surgical techniques and medical treatment, heart transplant patients still face complications such as rejection, infections, and drug toxicity. CT is a reliable tool for detecting most of these complications, whereas MR imaging is particularly adept at identifying pericardial pathologies and signs of rejection. Awareness of these nuances by radiologists, cardiologists, and surgeons is desired to optimize care, reduce morbidities, and enhance survival.

Chronic Tubercular Mediastinitis: A Rare Case Presentation With Subcutaneous Emphysema

Tuberculosis, histoplasmosis, various fungal infections, malignancy, and sarcoidosis are the most common causes of chronic or slowly progressing mediastinitis. Chronic mediastinitis of tubercular origin with subcutaneous emphysema is exceptionally uncommon, and the majority of cases are caused by trauma. Here we report the case of a 35-year-old chronic alcoholic male who presented to the Outpatient Department (OPD) with complaints of cough, chest pain, loss of weight, and intermittent low-grade fever for three months with no significant past medical history or family history for any respiratory diseases. He was admitted and all routine investigations were performed, which were normal including his chest X-ray, except erythrocyte sedimentation rate (ESR) which was raised. The patient's high-resolution Computed Tomography (HRCT) of the thorax was done which showed multiple pleural-based nodular lesions with few showing central cavitary nodules along with ground glass appearance. It also showed two fistulous tracks of 3.4-millimeter diameter, arising from the trachea at the T1 - T2 vertebral level and at the carina which led to the presence of air in the subcutaneous plane extending from the neck up to visualized abdomen suggestive of chronic mediastinitis with tracheal fistula, along with subcutaneous emphysema. This fistula was confirmed by video bronchoscopy as well as three-dimensional (3D) virtual bronchoscopy. A biopsy was taken, which was positive for acid-fast bacilli (AFB) stain, polymerase chain reaction (PCR) for tuberculosis, and positive tuberculin skin test. The patient was started on anti-tubercular treatment and on a follow-up visit upon completion of the intensive phase, his HRCT and video bronchoscopy showed fibrosing scarring with fistula closure.

Successful management of 72-h delay-detected blunt esophageal injury with trans-gastric primary repair; a case report and literature review

Diagnosis of blunt esophageal injury is currently a challenging issue. Early surgical interventions still play as the mainstay of treatment. There was no consensus about appropriate treatment options. However, it was potential morbidity if delayed management. We report a 33-year-old man with a history of a motorcycle accident who presented with hematemesis and epigastrium pain. He was initially diagnosed with left pneumohemothorax and low-grade gastric injury. The patient developed a high-grade fever with complex left pneumohemothorax 72-h after admission. The diagnostic studies revealed a lower esophageal rupture. He was treated with trans-gastric primary repair and recovered well with no complications. We propose the trans-gastric intraluminal repair is one of the surgical options in a blunt lower esophageal rupture.

Surgical Site Infection in Cardiac Surgery

Surgical site infections (SSIs) are one of the most significant complications in surgical patients and are strongly associated with poorer prognosis. Due to their aggressive character, cardiac surgical procedures carry a particular high risk of postoperative infection, with infection incidence rates ranging from a reported 3.5% and 26.8% in cardiac surgery patients. Given the specific nature of cardiac surgical procedures, sternal wound and graft harvesting site infections are the most common SSIs. Undoubtedly, DSWIs, including mediastinitis, in cardiac surgery patients remain a significant clinical problem as they are associated with increased hospital stay, substantial medical costs and high mortality, ranging from 3% to 20%. In SSI prevention, it is important to implement procedures reducing preoperative risk factors, such as: obesity, hypoalbuminemia, abnormal glucose levels, smoking and S. aureus carriage. For decolonisation of S. aureus carriers prior to cardiac surgery, it is recommended to administer nasal mupirocin, together with baths using chlorhexidine-based agents. Perioperative management also involves antibiotic prophylaxis, surgical site preparation, topical antibiotic administration and the maintenance of normal glucose levels. SSI treatment involves surgical intervention, NPWT application and antibiotic therapy.

Delayed Diagnosis of Pediatric Sternoclavicular Joint Infections and Clavicular Osteomyelitis During the COVID-19 Pandemic: A Report of 3 Cases

Sternoclavicular joint infections and osteomyelitis of the clavicle are extremely rare infections, especially in the pediatric population. Early signs of these infections are nonspecific and can be mistaken for common upper respiratory infections such as COVID-19 and influenza. Rapid diagnosis and treatment are critical for preventing potentially fatal complications such as mediastinitis. We present three cases of sternoclavicular joint infections in the past year during the COVID-19 pandemic. All three patients had delayed diagnoses likely secondary to COVID-19 workup. Each patient underwent surgical irrigation and débridement. Two of three patients required multiple surgeries and prolonged antibiotic courses. Placement of antibiotic-impregnated calcium sulfate beads into the surgical site cleared the infection in all cases where they were used. All three patients made a full recovery; however, the severity of their situations should not be overlooked. Children presenting to the hospital with chest pain, fever, and shortness of breath should not simply be discharged based on a negative COVID-19 test or other viral assays. A higher index of suspicion for bacterial infections such as clavicular osteomyelitis is important. Close attention must be placed on the physical examination to locate potential areas of concentrated pain, erythema, or swelling to prompt advanced imaging if necessary.

Prevention, Diagnosis and Management of Post-Surgical Mediastinitis in Adults Consensus Guidelines of the Spanish Society of Cardiovascular Infections (SEICAV), the Spanish Society of Thoracic and Cardiovascular Surgery (SECTCV) and the Biomedical Research Centre Network for Respiratory Diseases (CIBERES)

This is a consensus document of the Spanish Society of Cardiovascular Infections (SEICAV), the Spanish Society of Thoracic and Cardiovascular Surgery (SECTCV) and the Biomedical Research Centre Network for Respiratory Diseases (CIBERES). These three entities have brought together a multidisciplinary group of experts that includes anaesthesiologists, cardiac and cardiothoracic surgeons, clinical microbiologists, infectious diseases and intensive care specialists, internal medicine doctors and radiologists. Despite the clinical and economic consequences of sternal wound infections, to date, there are no specific guidelines for the prevention, diagnosis and management of mediastinitis based on a multidisciplinary consensus. The purpose of the present document is to provide evidence-based guidance on the most effective diagnosis and management of patients who have experienced or are at risk of developing a post-surgical mediastinitis infection in order to optimise patient outcomes and the process of care. The intended users of the document are health care providers who help patients make decisions regarding their treatment, aiming to optimise the benefits and minimise any harm as well as the workload.

Descending Mediastinitis in a Child: Diagnostic Challenges and a Different Treatment Approach

In children, spontaneous mediastinitis is a rare, severe and commonly misdiagnosed disease. Although standard of care treatment frequently involves surgery, we report a case of mediastinitis in a five-year-old child, successfully treated with 4 weeks of intravenous antibiotics. Ultrasound imaging was used to monitor patient response to conservative treatment while reducing radiation exposure.

Acute mediastinitis, mediastinal granuloma, and chronic fibrosing mediastinitis: A review

Acute mediastinitis is a rare infection that carries high morbidity and mortality. They are complications seen most often with deep sternal wound infections from surgeries with median sternotomies, oropharyngeal and odontogenic infections and esophageal perforations. These conditions should be promptly recognized and treated. Mediastinal granulomas are focal, mass-like lesions commonly resulting from prior granulomatous infections. They are regarded as benign, self-resolving lesions however can cause complications by compression of adjacent mediastinal structures. Chronic fibrosing mediastinitis is a rare, diffuse fibroinflammatory process most often seen with granulomatous infections and carries a worse prognosis than mediastinal granulomas especially when adjacent mediastinal structures are compromised. In this review, we discuss the epidemiology, etiology, clinical presentation, treatment and prognosis of acute mediastinitis, mediastinal granulomas, and chronic fibrosing mediastinitis.

Acute mediastinitis associated with tracheobronchial tuberculosis and aspergillosis: a case report and literature review

Acute mediastinitis (AM) is a rare but life-threatening disease. Here, we report a case of AM secondary to endobronchial tuberculosis (EBTB) and pseudomembranous Aspergillus tracheobronchitis (PMATB) co-infection. EBTB was confirmed by tissue culture for Mycobacterium tuberculosis and GeneXpert MTB/RIF (Cepheid, Sunnyvale, CA, USA) detection (simultaneous detection of M. tuberculosis and resistance to rifampin) using endobronchial biopsies; PMATB was confirmed by histopathology. Even with antibiotic treatment and systemic support treatment, the patient died of massive hemoptysis on day 10 after admission. When immunocompromised hosts have AM, especially with central airway involvement, EBTB and aspergillosis should be considered potential causes. Bronchoscopy is helpful for rapid diagnosis and administering precise treatment.

Thymic masses and mimics in adults: review of common and uncommon pathologies

The thymus is a primary lymphoid organ that plays a key role in the immune system development. Normally, it is located in the anterior mediastinum and it changes tissue composition with progressive fatty involution with age. The spectrum of pathological processes involving the thymus include enlargement, tumour development, and cystic change. In addition, other local pathology can mimic thymic disease. Differentiating these entities can be challenging; however, recognizing key features on imaging is essential to appropriately guide further investigation and therapy. The focus of this pictorial review will be to highlight the important distinguishing features of thymic hyperplasia, thymomas, thymic cysts, thymic neuroendocrine tumours (NETs), thymolipomas, mediastinal teratomas, and other mimics of thymic disease. Knowledge of the varying imaging findings on computed tomography and magnetic resonance imaging is valuable for radiologists to appropriately classify disease, avoid misdiagnosis, and expedite therapy.

Fungal fibrosing mediastinitis in pregnancy - Case report with review of literature

Fibrosing mediastinitis (FM) is characterized by extensive and invasive fibro-inflammatory proliferation, triggered by a delayed hypersensitivity reaction to variety of infective or noninfective stimuli. The infective agents often have a geographic distribution such as Histoplasma capsulatum in North America and Mycobacterium tuberculosis in Asian regions. In few reports, the mediastinitis is caused by fungi, particularly Aspergillus species. We report the first case of possible aspergillous FM in a young pregnant woman.

Utility of FDG-PET/CT for the Detection and Characterization of Sternal Wound Infection Following Sternotomy

Purpose

FDG-PET/CT has the potential to play an important role in the diagnosis of sternal wound infections (SWI). The purpose of this study was to analyze the diagnostic accuracy of FDG-PET/CT for SWI in patients following sternotomy.

Methods

We performed a single-center, retrospective analysis of patients who had undergone median sternotomy and FDG-PET/CT imaging. The gold standard consisted of positive bacterial culture and/or the presence of purulent material at surgery. Qualitative patterns of sternal FDG uptake, SUV_max, and associated CT findings were determined, and an imaging scoring system was developed. The diagnostic performances were studied in both the recent (≤ 6 months between sternotomy and imaging) and remote surgery phase (> 6 months).

Results

A total of 40 subjects were identified with 11 confirmed SWI cases. Consensus interpretation was associated with a sensitivity of 91% and specificity of 97%. Combination of uptake patterns yielded an AUC of 0.96 while use of SUVmax yielded an AUC of 0.82.

Conclusions

Results suggest that FDG-PET/CT may be useful for the diagnosis of SWI with optimal diagnostic accuracy achieved by identifying specific patterns of uptake. SUV_max can be helpful in assessing subjects with remote surgery, but its use is limited in the context of recent surgery. Further studies are required to confirm these results.

A Fatal Mediastinitis Due to a Neck Trauma from an Undeclared Assault

History of neck trauma should be promptly investigated in patients with severe infections of the chest as mediastinitis. We present a forensic case of a death due to a mediastinitis in a patient with an undetected fracture of the superior horn of the thyroid cartilage that was exclusively revealed at autopsy examination. Histological analyses of the neck tissues showed signs of pharyngeal mucosal microperforation caused by the fracture and surrounded by an inflammatory reaction. The fracture was caused by a not declared manual strangulation attempt, happened several days before medical evaluations. We share our experience to emphasize the importance of revealing the etiologies of fatal infections of the mediastinum both for clinical and forensic purposes.

Mediastinal and Pleural MR Imaging: Practical Approach for Daily Practice

Radiologists in any practice setting should be prepared to use thoracic magnetic resonance (MR) imaging for noncardiac and nonangiographic applications. This begins with understanding the sequence building blocks that can be used to design effective thoracic MR imaging protocols. In most instances, the sequences used in thoracic MR imaging are adapted from protocols used elsewhere in the body. Some modifications, including the addition of electrocardiographic gating or respiratory triggering, may be necessary for certain applications. Once protocols are in place, recognition of clinical scenarios in which thoracic MR imaging can provide value beyond other imaging modalities is essential. MR imaging is particularly beneficial in evaluating for benign features in indeterminate lesions. In lesions that are suspected to be composed of fluid, including mediastinal cysts and lesions composed of dilated lymphatics, MR imaging can confirm the presence of fluid and absence of suspicious enhancement. It can also be used to evaluate for intravoxel lipid, a finding seen in benign residual thymic tissue and thymic hyperplasia. Because of its excellent contrast resolution and potential for subtraction images, MR imaging can interrogate local treatment sites for the development of recurrent tumor on a background of post-treatment changes. In addition to characterization of lesions, thoracic MR imaging can be useful in surgical and treatment planning. By identifying nodular sites of enhancement or areas of diffusion restriction within cystic or necrotic lesions, MR imaging can be used to direct sites for biopsy. MR imaging can help evaluate for local tumor invasion with the application of "real-time" cine sequences to determine whether a lesion is adherent to an adjacent structure or surface. Finally, MR imaging is the modality of choice for imaging potential tumor thrombus. By understanding the role of MR imaging in these clinical scenarios, radiologists can increase the use of thoracic MR imaging for the benefit of improved decision making in the care of patients. ^©RSNA, 2018.

Current perspectives on diagnosis and management of sternal wound infections

Deep sternal wound infection (DSWI), also known as mediastinitis, is a serious and potentially fatal condition. The diagnosis and treatment of DSWI are challenging. In this current narrative review, the epidemiology, risk factors, diagnosis, and surgical and antimicrobial management of DSWI are discussed. Ideally, the management of DSWI requires early and sufficient surgical debridement and appropriate antibiotic therapy. When foreign material is present, biofilm-active antibiotic therapy is also needed. Because DSWI is often complex, the management requires the involvement of a multidisciplinary team consisting of cardiothoracic surgeons, plastic surgeons, intensivists, infectious disease specialists, and clinical microbiologists.

[Acute and chronic mediastinitis]

BACKGROUND

A systematic approach to the etiology and possible course of acute mediastinitis is a prerequisite for adequate diagnostics and therapy. Chronic mediastinitis represents a rarity in the clinical practice.

MATERIAL AND METHOD

A selective literature search was carried out.

RESULTS

An acute infection of the mediastinum occurs after perforation of mediastinal structures, such as the esophagus and trachea mostly of iatrogenic origin and as descending necrotizing mediastinitis (DNM) from oropharyngeal foci. The mortality rate of esophageal injuries, irrespective of the cause is currently given as 12 %. A DNM results from an unobstructed spread along the cervicothoracic spaces and is a severe infection which manifests as a clinical picture of sepsis. The mortality rate given in the currently available literature is 14 %. Chronic mediastinitis is a very rare condition which is characterized by the proliferation of fibrous and collagenous tissue in the mediastinum. Whereas the pathogenesis remains unclear, there are indications for a Histoplasma capsulatum infection as the causal link. The prognosis is good.

CONCLUSION

After perforation of the esophagus or trachea there is always the risk of an infection of the mediastinum; therefore, the diagnosis is followed by further evaluation and early therapy. The DNM can cause unspecific symptoms of sepsis without an obvious focal point. It is important to be aware of a possible correlation between an oropharyngeal center of infection and mediastinitis in order to initiate appropriate diagnostic imaging in cases with the slightest suspicion. Chronic mediastinitis is a rare condition with varying courses and can be difficult to diagnose. An histological clarification for distinction from malignant diseases appears to be a sensible approach.

Bronchopulmonary foregut malformation presenting as extralobar pulmonary sequestration associated with a bronchogenic cyst: an unusual clinical and radiological feature in an adolescent patient

We present a case of symptomatic complex bronchopulmonary foregut malformation (BPFM), including extralobar pulmonary sequestration and a bronchogenic cyst, in the left anterior mediastinum of a 15-year-old boy. Preoperative computed tomography showed a cystic mass with heterogeneous enhancement of adjacent soft tissue components and pleural effusion. We suggested the infected bronchogenic cyst as the first impression. However, pathological examination after surgical resection revealed extralobar pulmonary sequestration and a bronchogenic cyst with unusual manifestation, which was located in the left upper hemithorax and supplied by the pulmonary artery. In patients presenting with a cystic mass with features of inflammation or infection and collateral vasculature, the possibility of a complex bronchopulmonary foregut malformation should be considered in the differential diagnosis.

Pulmonary Infections: Imaging with CT

Computed tomography (CT) plays a key role in various kinds of pulmonary infections especially in immunocompromised patients, owing to its much higher sensitivity and specificity than the traditionally performed chest X-ray. CT permits the detection of the main infectious pattern and associated findings with high confidence and allows for the precise assessment of all involved structures, to potentially guide a bronchoalveolar lavage or another diagnostic procedure, and to ensure a reliable follow-up. It may be performed at a carefully chosen dose, which may nearly reach that of a chest X-ray in specific situations. The importance of post-processing tools is undeniable in some conditions, in particular for the evaluation of micronodules in the immunocompromised population. The wide spectrum of features of specific organisms according to the immune status, such as in aspergillosis or tuberculosis, must be known, as well as the potential of atypical presentations in case of Pneumocystis jirovecii (PCP) pneumonia when occurring in non-HIV immunocompromised patients. In all cases, underlying disorders must be considered as well as all the differential diagnoses. Overall, CT definitely helps clinicians to diagnose pulmonary infections and to make treatment decisions, especially in vulnerable patients.

Causal inference regarding infectious aetiology of chronic conditions: a systematic review

BACKGROUND

The global burden of disease has shifted from communicable diseases in children to chronic diseases in adults. This epidemiologic shift varies greatly by region, but in Europe, chronic conditions account for 86% of all deaths, 77% of the disease burden, and up to 80% of health care expenditures. A number of risk factors have been implicated in chronic diseases, such as exposure to infectious agents. A number of associations have been well established while others remain uncertain.

METHODS AND FINDINGS

We assessed the body of evidence regarding the infectious aetiology of chronic diseases in the peer-reviewed literature over the last decade. Causality was assessed with three different criteria: First, the total number of associations documented in the literature between each infectious agent and chronic condition; second, the epidemiologic study design (quality of the study); third, evidence for the number of Hill's criteria and Koch's postulates that linked the pathogen with the chronic condition. We identified 3136 publications, of which 148 were included in the analysis. There were a total of 75 different infectious agents and 122 chronic conditions. The evidence was strong for five pathogens, based on study type, strength and number of associations; they accounted for 60% of the associations documented in the literature. They were human immunodeficiency virus, hepatitis C virus, Helicobacter pylori, hepatitis B virus, and Chlamydia pneumoniae and were collectively implicated in the aetiology of 37 different chronic conditions. Other pathogens examined were only associated with very few chronic conditions (≤ 3) and when applying the three different criteria of evidence the strength of the causality was weak.

CONCLUSIONS

Prevention and treatment of these five pathogens lend themselves as effective public health intervention entry points. By concentrating research efforts on these promising areas, the human, economic, and societal burden arising from chronic conditions can be reduced.

[A case of conservatively resolved intramural esophageal dissection combined with pneumomediastinum]

Intramural esophageal dissection (IED) is a rare form of esophageal injury. We report a rare case of spontaneous IED complicated with pneumomediastinum and successfully improved by conservative management. A 46-year-old man presented to the emergency department with chest pain and hematemesis. The endoscopic diagnosis was suspicious of IED. Chest CT scan performed to rule out complication noted IED combined with pneumomediastinum. He was managed conservatively with nil per oral, intravenous antibiotics and parenteral nutrition. Follow up study after 2 weeks later showed near complete resolution of IED. IED should be included in the differential diagnosis for unexplained acute chest pain, especially, associated with dysphagia and hematemesis. IED with pneumomediastinum or mediastinitis require prompt surgery. So far, there is no case report of IED combined with pneumomediastinum which resolved without surgical treatment. In this case, IED combined with pneumomediastinum has improved by conservative management, so we present a case report.

Evaluation of prognostic value of selected biochemical markers in surgically treated patients with acute mediastinitis

BACKGROUND

Monitoring of biochemical markers of inflammation in acute mediastinitis (AM) can be useful in the modification of treatment. This study was a retrospective evaluation of selected biochemical parameters with negative impact on the prognosis in surgically treated patients.

MATERIAL/METHODS

There were 44 consecutive patients treated surgically due to AM of differentiated etiology. Selected biochemical markers (WBC, RBC, HGB, HCT, PLT, CRP, PCT, ionogram, protein and albumins) were assessed before surgery and on the 3rd day after surgery. ANOVA was applied to find factors influencing observations. Numerical data [laboratory parameters] were compared by means of medians.

RESULTS

The overall hospital mortality rate was 31.82%. In the group of dead patients, there were observed statistically significant lower mean preoperative values of RBC [p=0.0090], HGB [p=0.0286], HCT [p=0.0354], protein [p= 0.0037], albumins [p=0.0003] and sodium [p<0.0001] and elevated values of CRP [P=0.0107] and PCT p<0.0001]. High level of inflammatory markers on day 3 after surgery was found to increase the risk of death - for WBC (by 67%), for CRP (by 88%) and for PCT (by 100%).

CONCLUSIONS

Poor prognosis was more frequent in patients with preoperative high levels of CRP, PCT, anemia, hypoproteinemia and hyponatremia. The risk of death increases significantly if in the immediate postoperative period no distinct decrease in WBC count and of the CRP and PCT level is observed. In such a situation the patients should be qualified earlier for broadened diagnostic workup and for reoperation.

Proposal for a recovery prediction method for patients affected by acute mediastinitis

BACKGROUND

An attempt to find a prediction method of death risk in patients affected by acute mediastinitis. There is not such a tool described in available literature for that serious disease.

METHODS

The study comprised 44 consecutive cases of acute mediastinitis. General anamnesis and biochemical data were included. Factor analysis was used to extract the risk characteristic for the patients. The most valuable results were obtained for 8 parameters which were selected for further statistical analysis (all collected during few hours after admission). Three factors reached Eigenvalue >1. Clinical explanations of these combined statistical factors are: Factor1 - proteinic status (serum total protein, albumin, and hemoglobin level), Factor2 - inflammatory status (white blood cells, CRP, procalcitonin), and Factor3 - general risk (age, number of coexisting diseases). Threshold values of prediction factors were estimated by means of statistical analysis (factor analysis, Statgraphics Centurion XVI).

RESULTS

The final prediction result for the patients is constructed as simultaneous evaluation of all factor scores. High probability of death should be predicted if factor 1 value decreases with simultaneous increase of factors 2 and 3. The diagnostic power of the proposed method was revealed to be high [sensitivity =90%, specificity =64%], for Factor1 [SNC = 87%, SPC = 79%]; for Factor2 [SNC = 87%, SPC = 50%] and for Factor3 [SNC = 73%, SPC = 71%].

CONCLUSION

The proposed prediction method seems a useful emergency signal during acute mediastinitis control in affected patients.

Nonvascular, nontraumatic mediastinal emergencies in adults: a comprehensive review of imaging findings

Given their high frequency, mediastinal emergencies are often perceived as being a result of external trauma or vascular conditions. However, there is a group of nonvascular, nontraumatic mediastinal emergencies that are less common in clinical practice, are less recognized, and that represent an important source of morbidity and mortality in patients. Nonvascular, nontraumatic mediastinal emergencies have several causes and result from different pathophysiologic mechanisms including infection, internal trauma, malignancy, and postoperative complications, and some may be idiopathic. Some conditions that lead to nonvascular, nontraumatic mediastinal emergencies include acute mediastinitis; esophageal emergencies such as intramural hematoma of the esophagus, Boerhaave syndrome, and acquired esophagorespiratory fistulas; spontaneous mediastinal hematoma; tension pneumomediastinum; and tension pneumopericardium. Although clinical findings of nonvascular, nontraumatic mediastinal emergencies may be nonspecific, imaging findings are often definitive. Awareness of various nonvascular, nontraumatic mediastinal emergencies and their clinical manifestations and imaging findings is crucial for making an accurate and timely diagnosis to facilitate appropriate patient management.

Postoperative mediastinitis due to Finegoldia magna with negative blood cultures

We report a case of Finegoldia magna (formerly known as Peptostreptococcus magnus) mediastinitis following coronary artery bypass in a 50-year-old patient. Even if staphylococci remain the main causative organism of postoperative mediastinitis, the responsibility of anaerobic bacteria must be considered in cases of fever and sternal drainage with negative blood cultures.

Para-aortic arch abscess secondary to Staphylococcus aureus pneumonia

Staphylococcus aureus is a relatively common pathogen causing pneumonia in the community, hospital ward and intensive care unit. Although pneumonia is responsible for significant morbidity and mortality, especially in elderly and immunocompromised patients, it is usually uncomplicated and resolves without complications. The case of a woman who developed a para-aortic abscess after a community-acquired S aureus pneumonia infection is presented. A number of diagnostic imaging modalities were used to reach the diagnosis. This complication has not been reported previously and it is likely secondary to suppurative lymphadenitis of a station 5 or 6 node. The patient was successfully managed nonsurgically with computed tomography-guided drainage and intravenous antibiotics.

Mediastinite aguda: aspectos de imagem pós-cirurgias cardíacas na tomografia computadorizada de multidetectores

Mediastinite pós-cirurgias torácicas é definida como a infecção dos órgãos e tecidos do espaço mediastinal, ocorrendo em 0,4% a 5% dos casos. A gravidade da infecção pós-operatória varia desde infecção de tecidos superficiais da parede torácica até mediastinite fulminante com envolvimento esternal. O critério diagnóstico da tomografia computadorizada para mediastinite aguda pós-cirúrgica é a presença de coleção mediastinal, podendo estar associada ou não a anormalidades periesternais como edema/borramento de partes moles, separação dos segmentos esternais com reabsorção óssea marginal, esclerose e osteomielite. Achados associados incluem linfonodomegalias, consolidações pulmonares e derrame pleural e pericárdico. Pequenas coleções e gás mediastinais podem ser usualmente encontradas em pós-operatório recente de cirurgias torácicas sem a presença de infecções, limitando a eficácia da tomografia computadorizada nas duas primeiras semanas. Após esse período, a tomografia alcança quase 100% de sensibilidade e especificidade. Pacientes com suspeita clínica de mediastinite devem ser submetidos a exame de tomografia para pesquisa de coleções, identificando a extensão da doença e sua natureza. A versão de multidetectores propicia recursos de reconstruções em diversos planos e janelas, contribuindo especialmente para o estudo do esterno.

Intra-abdominal and gastrointestinal tuberculosis

OBJECTIVE

Reports suggest that the rates of tuberculosis (TB) continue to rise in the UK and throughout the world. The spread of the disease is aided by poverty, overcrowding, co-infection with human immunodeficiency virus and drug resistance. Consistent with the overall trend, intra-abdominal and gastrointestinal (GI) TB rates are rising. Tuberculosis is a treatable disease, whether occurring in the lungs or at extra-pulmonary sites but the nonspecific features of the disease result in difficulty in establishing a diagnosis. In this report, we have concentrated on the benefits and potential pitfalls of diagnostic methods.

METHOD

A literature review was performed using the National Library of Medicine's Pubmed Database using the keywords diagnosis, management, abdominal and GI TB.

RESULTS

Abdominal TB presents a particular challenge, as the diverse features of the disease do not readily suggest a particular diagnosis and diagnostic delays lead to significant morbidity and mortality. A number of investigative methods have been used to aid in the diagnosis of abdominal and GI TB.

CONCLUSION

The nonspecific presentation of abdominal and GI TB present challenges in the diagnosis of this increasingly common disease. A high index of suspicion is an important factor in early diagnosis. After a diagnosis has been established, prompt initiation of treatment helps prevent morbidity and mortality.

A Potential Role for F-18 FDG PET/CT in Evaluation and Management of Fibrosing Mediastinitis

Fibrosing mediastinitis is an uncommon benign disorder, and its pathogenesis and management remain unclear. Conventional imaging techniques (chest radiographs, CT, MRI) may suggest its diagnosis but are frequently nonspecific, and it frequently mimics a malignant process by presenting as a mediastinal mass without calcifications, encasing, and infiltrating adjacent mediastinal structures, and showing an overall aggressive behavior. The value of FDG PET imaging in this entity remains largely unknown with only a few case reports in the literature, and often, biopsy is necessary for definitive diagnosis. We report a case of biopsy proven fibrosing mediastinitis highlighting the utility of PET in the evaluation and management of the disease.

Treatment of perforation in the healthy esophagus: analysis of 12 cases

BACKGROUND

Perforation of the esophagus still carries high morbidity and mortality rates, and there is no gold standard for the surgical treatment of choice.

MATERIALS AND METHODS

We reviewed the records of patients treated for esophageal perforation in the last decade at the General Surgery Unit of the University of Udine. Patients suffering from perforation secondary to surgical procedures or neoplastic disease were ruled out.

RESULTS

Eight males (66.7%) and four females (33.3%) met the inclusion criteria. The cause of perforation was iatrogenic in seven cases (58.3%) and spontaneous in five (41.7%). The perforation was in the cervical esophagus in five cases (41.7%) and at thoracic level in the other seven (58.3%). Two patients (16.7%) with cervical lesions were treated conservatively; two (16.7%) underwent primary closure and the insertion of a drainage tube; one patient with a distal cervical lesion underwent diversion esophagostomy; six patients had resection of the entire thoracic esophagus and terminal cervical esophagostomy; one had segmental resection of the distal thoracic esophagus and lateral diversion esophagostomy. In the five patients whose reconstruction was postponed, esophagogastroplasty surgery was performed with an anastomosis at cervical level in four cases and at thoracic level in one. The global mortality rate was 25%. Late diagnosis-more than 24 h after the perforation event-seems to be the only factor correlated with fatal outcome (p = 0.045).

CONCLUSIONS

The choice of treatment for perforation in a healthy esophagus depends mainly on the site and size of the lesion. Cervical lesions may be amenable to conservative treatment or require primary surgical repair, while thoracic lesions with associated sepsis or major loss of substance demand an aggressive approach, with esophageal resection and delayed reconstruction seeming to be the safest option.

[An unusual mediastinal opacity]

A 36-year old immunocompetent male from Senegal with an uneventful history was admitted for exploration of a bullous collection in the posterior mediastinum. Multifocal tuberculosis was diagnosed. Computed tomography-guided drainage removed 600 cc of caseum. The diagnosis as rupture of intrathoracic Pott's abscess complicated by a probably esophageal fistula. The clinical course was rapidly favorable with later development of mediastinal fibrosis. This uncommon case illustrates the contribution of interventional radiology recently developed in the Principal Hospital in Dakar, Senegal.

Esophageal perforation: principles of diagnosis and surgical management

PURPOSE

Esophageal perforation (EP) is still associated with a high mortality rate, even after surgical repair. We reviewed 17 cases of EP to evaluate the management of this major surgical problem.

METHODS

We reviewed the medical records of all patients treated for EP in our department between November 2001 and November 2004. Therapy was based on various patient-related factors.

RESULTS

Seventeen patients, with a mean age of 63 years, presented with EP mostly caused by iatrogenic incidents (11/17). In nine patients, the perforation was located in the thoracic segment, with a mean size of 2.5 +/- 0.6 cm. Thoracic computed tomography (CT) was performed in all patients to assess the periesophageal inflammation precisely. More than 50% showed signs of systemic inflammation indicative of sepsis, reflected by a dramatic increase in serum C-reactive protein and leukocytosis. Treatment consisted of debridement and drainage (n = 3), primary repair (n = 3), reinforced repair (n = 4), esophageal resection (n = 5), and conservative measures (n = 2). All patients, except for three with pre-existing liver dysfunction and other comorbidities, survived, representing a mortality rate of 17.6% (14/17). An analysis of the literature (2000-2005) revealed an overall mortality rate of 19.7% (101/521), ranging from 3% to 67%.

CONCLUSION

Our data support the individualized surgical management of EP, based on careful evaluation of various patient-related factors, including CT findings.

Descending mediastinitis: a review

CONTEXT

Mediastinitis is an inflammation of connective tissue that involves mediastinal structures. When the condition has an infectious origin located in the cervical or oral region, it is termed "descending mediastinitis" (DM).

DATA SOURCES

The subject was examined in the light of the authors' own experiences and by reviewing the literature available on the subject. The Medline, Lilacs and Cochrane databases were searched for articles, without time limits, screening for the term "descending mediastinitis". The languages used were English and Spanish.

DATA SYNTHESIS

There are three main fascial pathways by which oral or cervical infections can reach the mediastinum: pretracheal, lateropharyngeal and retropharyngeal. About 70% of DM cases occur via the retropharyngeal pathway. The mortality rate is about 50%. According to infection extent, as seen using computed tomography, DM can be classified as focal (type I) or diffuse (type II). The clinical manifestations are nonspecific and resemble other systemic infections or septic conditions. The primary treatment for DM consists of antibiotics and surgical drainage. There are several approaches to treating DM; the choice of approach depends on the DM type and the surgeon's experience. In spite of all the improvements in knowledge of the microbiology and physiopathology of the disease, controversies still exist regarding the ideal duration of antibiotic therapy and whether tracheostomy is really a necessary procedure.

CONCLUSION

Since DM is a lethal condition if not promptly treated, it must always be considered to represent an emergency situation.

Kritische odontogene Infektion mit Mediastinalbeteiligung

BACKGROUND

Occasionally, trivial odontogenic infections may develop into complex diseases. This may even result in an unrestrained phlegmonous spread causing life-threatening complications. These problems have decreased since the introduction of antibiotics and also due to improved oral hygiene and improved diagnostic measures resulting in optimized medical treatment. However, life-threatening forms are still seen, in particular if infections spread along the cervical fascial sheaths down towards to the mediastinum. Over the past decade the number of critical infections has increased in other medical specialties. This is usually explained by the development of multiresistant pathogens in the context of nosocomial infections.

PATIENTS AND METHODS

We reviewed the patients' records of the past 15 years at the Department of Oral and Maxillofacial Surgery of the University Hospital Kiel to assess a possible increase of odontogenic infections with life-threatening complications. From 1990 to 2004, four patients with odontogenic infections exhibiting critical phlegmonous spread were treated in the intensive care unit. Two patients developed bacterial mediastinitis which could be controlled by intravenous antibiotics only. One patient progressed to general septic mediastinitis and eventually died of cardiorespiratory arrest. The last patient also had septic mediastinitis and developed right pleural empyema. Several operations were necessary before the disease could be controlled. This patient's case report is presented in detail.

CONCLUSION

The prognosis of patients with mediastinitis crucially depends on (a) early diagnosis including computed tomography of the neck and thorax, (b) early radical surgical intervention, and (c) optimized pathogen-oriented antibiotic treatment.

Mediastinal histoplasmosis: report of the first two Brazilian cases of mediastinal granuloma

This report documents the first two Brazilian cases of mediastinal granuloma due to histoplasmosis, presenting selected aspects on the diagnosis. Tissue samples revealing histoplasmosis were obtained from each of the patients by mediastinoscopy and thoracotomy. In the second patient, a subcarinal calcified mass eroded into the bronchial tree, leading to secondary bilateral aspiration pneumonitis one week after thoracotomy. Although rare, histoplasmosis should be included in the differential diagnosis of mediastinal granuloma, specially if there are calcifications greater than 10 mm in dimension.