Multifocal Areas Of Consolidation Research Articles

Can You Establish the Cause of This Patient's Shortness of Breath?

Mr. B is a 56-year-old man diagnosed with metastatic HER2-positive gastroesophageal adenocarcinoma. He received front-line leucovorin, 5-fluorouracil, and oxaliplatin (FOLFOX) and trastuzumab for 10 months before restaging imaging revealed progressive disease. He then received second-line trastuzumab deruxtecan. His treatment was complicated by several admissions felt to be unrelated to his cancer therapy. He was discharged after an episode of pneumonia on a steroid taper with prophylactic trimethoprim/sulfamethoxazole. Once he recovered, he was given a fourth dose of chemotherapy. About a week later, wheezes were noticed on physical exam, and he was given a 5-day course of levofloxacin. Around the same time, he also finished his steroid taper. Twelve days after his dose of chemotherapy, he presented to the emergency room with 3 to 4 days of progressive shortness of breath and dry cough following the completion of levofloxacin without symptom improvement. A CT scan showed increasing airspace opacities and multifocal areas of consolidation. Blood, nasal, and sputum cultures were negative. A bronchoscopy was performed that did not reveal findings concerning for capillaritis. He was ultimately diagnosed with drug-induced pneumonitis/interstitial lung disease (ILD). Mr. B continued to experience worsening hypoxic respiratory failure despite continuous IV steroids. He was discharged to an inpatient hospice facility where he passed away 2 weeks later. Drug-induced pneumonitis/ILD should be considered in all patients receiving trastuzumab deruxtecan who develop progressive shortness of breath or other respiratory complaints.

Co-infection of COVID-19 and influenza A in a hemodialysis patient: a case report

BackgroundCoronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus that was first discovered in December 2019 in Wuhan, China. With the growing numbers of community spread cases worldwide, the World Health Organization (WHO) declared the COVID-19 outbreak as a pandemic on March 11, 2020. Like influenza viruses, SARS-CoV-2 is thought to be mainly transmitted by droplets and direct contact, and COVID-19 has a similar disease presentation to influenza. Here we present a case of influenza A and COVID-19 co-infection in a 60-year-old man with end-stage renal disease (ESRD) on hemodialysis.Case presentationA 60-year-old man with ESRD on hemodialysis presented for worsening cough, shortness of breath, and diarrhea. The patient first developed a mild fever (37.8 °C) during hemodialysis 3 days prior to presentation and has been experiencing worsening flu-like symptoms, including fever of up to 38.6 °C, non-productive cough, generalized abdominal pain, nausea, vomiting, and liquid green diarrhea. He lives alone at home with no known sick contacts and denies any recent travel or visits to healthcare facilities other than the local dialysis center. Rapid flu test was positive for influenza A. Procalcitonin was elevated at 5.21 ng/mL with a normal white blood cell (WBC) count. Computed tomography (CT) chest demonstrated multifocal areas of consolidation and extensive mediastinal and hilar adenopathy concerning for pneumonia. He was admitted to the biocontainment unit of Nebraska Medicine for concerns of possible COVID-19 and was started on oseltamivir for influenza and vancomycin/cefepime for the probable bacterial cause of his pneumonia and diarrhea. Gastrointestinal (GI) pathogen panel and Clostridioides difficile toxin assay were negative. On the second day of admission, initial nasopharyngeal swab came back positive for SARS-CoV-2 by real-time reverse-transcriptase polymerase chain reaction (RT-PCR). The patient received supportive care and resumed bedside hemodialysis in strict isolation, and eventually fully recovered from COVID-19.ConclusionsWe presented a case of co-infection of influenza and SARS-CoV-2 in a hemodialysis patient. The possibility of SARS-CoV-2 co-infection should not be overlooked even when other viruses including influenza can explain the clinical symptoms, especially in high-risk patients.

Chest Multi Detector Computed Tomography Findings among Patients with H1N1 Influenza A Infection: A Retrospective Study

Introduction: The first cases of H1N1 Influenza A occurred in Mexico in 2009, thereafter the infection rapidly spread worldwide. Seasonal epidemics and unpredictable pandemics had been declared by the World Health Organisation (WHO), since then. Aim: To describe the Thoracic Multi-Detector Computed Tomography (MDCT) findings in moderate to severely ill, H1N1 patients during epidemic spread. Materials and Methods: A retrospective observational study was done in which evaluation of 155 hospitalised patients confirmed to have H1N1 Influenza A epidemic infection between October 2018-December 2018, through the radiologic and clinical aspects. About 56 moderate to severely ill patients, who failed to improve with through treatment, underwent thoracic cross-sectional MDCT and their scans available on picture archiving and communication system (PACS) were assessed and radiological findings were evaluated with respect to clinical condition. Descriptive statistics were used for representation of data. Results: About 56 moderate to severely ill H1N1 patients who underwent chest MDCT, consisted of 30 males and 26 females ranging in age from 20 to 86 years with median age of 55.19 years. Ground glass opacities was found in 34 (60.71%) patients, Consolidation in 33 (58.93%) patients, combined Ground glass pattern and Consolidation in 18 (32.14%) patients and Acinar nodules in 21 (37.50%) patients. Combined Peripheral & Central distribution of lesions was found in 47 (83.92%) patients and central lesions in 6 (10.71%) patients. The lesions were multifocal in 51 (91.07%) patients and diffuse in 25 (44.64 %) patients. Lesions seen in bilateral all lobes in 25 (44.6%) patients and unilateral in 7 (12.5%) patients. Small mediastinal Lymphnodes were detected in 42 (75%) patients, pleural effusion was associated in 18 (32.14%) patients and pericardial effusion in 4 (7.14%) patients. In nonvulnerable group, 53 (94.6%) patients showed full recovery as in those patients therapy was started earlier while in vulnerable group 3 (5.35%) died immediately after infection. Conclusion: Unilateral or bilateral ground-glass opacities may or may not be linked with focal or multifocal areas of consolidation in the peribronchovascular and subpleural distribution that resembled the appearance of organising pneumonia is the main finding which was observed.

Lung Adenocarcinoma with Miliary Metastases and Left Femur Pathologic Fracture: an Unusual Case Mimicking Disseminated Tuberculosis

Lung adenocarcinoma can have a varied appearance at presentation. Solid, ground-glass, or part-solid and part-ground-glass nodules are commonly seen [1]. Multifocal areas of consolidation that are peribronchovascular and contain air bronchograms may also be identified [3]. Multiple discrete nodules, or the so-called miliary pattern, are rare, with few cases reported in the literature [3, 10, 12, 14]. This pattern is more commonly reported as multifocal or diffuse adenocarcinoma, and detailed data regarding the incidence has not yet been studied in depth. However, in one case report of 73 patients with adenocarcinoma, 14 presented with multifocal disease, though only one had innumerable discrete nodules [19, 22]. In another study examining 548 patients with non-small cell lung cancer, 504 patients presented with a dominant lesion (stage I disease) and 44 with multifocal disease. Of the 44 patients, 18 had multifocal adenocarcinoma [2]. Some have suggested that the miliary pattern of adenocarcinoma may be produced by bone or liver metastases that continually seed the lung, though this has yet to be verified [10]. Because the miliary pattern is much less common, it may be confused for other entities, such as tuberculosis. Non-small cell lung cancer metastasizes to the bone in approximately 15–40% of cases, mostly involving the axial skeleton [11, 16]. Appendicular metastases are more common proximal to the knee and elbow, though more distal involvement is reported [5, 9, 11, 15, 18, 20, 21]. Extremity metastases are often initially misdiagnosed as benign entities such as infection due to presenting symptoms of local redness, pain, and swelling. Generally, a bony metastasis on radiograph appears as a lytic lesion and may be centered in the cortex (cookie-bite lesion). There may or may not be a demonstrable soft tissue mass [7]. Tuberculous and malignant involvement of the bone is often indistinguishable on imaging, particularly in the spine, where MRI findings can be similar [4, 13, 17, 23]. Diagnosis of tuberculous spread to the bone in general is often difficult, with an average delay in diagnosis of 16–19 months [4]. The musculoskeletal system is involved in 1–3% of cases of tuberculosis. The femur, tibia, and small bones of the hands and feet are often affected [6]. Typically, the metaphyses are involved, with radiographic features that include osteopenia and poorly defined lytic lesions with minimal surrounding sclerosis [4]. Our goal is to highlight the importance of maintaining a broad differential when evaluating a patient with confounding risk factors and imaging findings. Premature diagnoses may lead to delays in appropriate management [13]. Ultimately, tissue sampling may be necessary in providing a definitive, timely diagnosis.

Bronchopulmonary Aspergillosis Associated with Acute Myocardial Infarction in Dog

Background: Fungi of the genus Aspergillus are ubiquitous microorganisms of opportunistic character, of which animals and humans are continually exposed. Are described three main forms of aspergillosis in dogs: nasal, disseminated and bronchopulmonary. This form which is restricted to the lung parenchyma is considered rare in dogs. The aim of this paper is to report a case of pulmonary aspergillosis associated to acute myocardial infarction in a dog, focusing on epidemiological, clinical, pathological and immunohistochemical characteristics. Case: A male dog, 4-year-old, Pinscher, clinically presented dyspnea, anorexia, vomiting, concentrated urine and dark and mollifed faeces. On physical examination, there were congested oral and conjunctival mucosas, dehydration and petechiae in the outer ear. The animal died fve days after the clinical attendance and was sent for necropsy. The macroscopic lesions were restricted to the lung, heart and liver. There were multifocal areas of consolidation in the lung parenchyma and yellowish content in the trachea and bronchi lumen. The heart was rounded and with pale areas in the myocardium. Liver was discreet accentuation of the lobular pattern. Histologically the lesion was characterized by pyogranulomatous and necrotizing bronchopneumonia, multifocal to coalescing, moderate, associated with myriads of intralesional hyphae consistente with Aspergillus spp., associated with acute myocardial infarction. The hyphae weakly stained basophilic by hematoxylin and eosin were strongly impregnated by Grocott’s methenamine silver nitrate and showed strong immunolabelling of the cytoplasm, which were evidenced in brown. There were areas of acute myocardial infarction and hepatocellular degeneration and congestion in the liver, although fungal hyphae were not observed in these tissues. Discussion: The diagnosis of pulmonary aspergillosis was established based on the morphological and tinctorial characteristics of the agent and confrmed by immunohistochemistry. In this case, is not included in the clinical history any conditions that could promote immunosuppression, neither were observed morphological changes in the pathological examination which suggested other intercurrent diseases. It is likely that the dog has been exposed to the inhalation of large amounts of conidia for a long period of time, condition that favors the occurrence of the disease, even in immunocompetent animals. Probably were not evidenced severe respiratory clinical signs, that characterize the pulmonary impairment, due to the shortcourse of the disease. The pyogranulomatous and necrotizing inflammatory reaction is typical of fungal infection and was restricted to the lung parenchyma. The areas of coagulation necrosis observed in the myocardium are probably secondary to vascular injury caused by the fungi, with subsequent thromboembolism, ischemia and infarction. In Brazil, there are few reports of aspergillosis in dogs, have been reported the nasal and systemic forms. In the world literature, there are few reports about this bronchopulmonary form of the disease. Although uncommon, pulmonary aspergillosis should be considered in the differential diagnosis of diseases that affect the lower respiratory tract of dogs, as well as it’s systemic complications resulting from angioinvasive characteristic of the fungus, which in this case was determinant to the death of the animal. Keywords: Aspergillus, fungal disease, respiratory tract

Findings in children severely infected with a novel influenza A virus of swine origin: pulmonary imaging

BackgroundThis article reviews the chest radiography of children with severe infection caused by a novel influenza A (H1N1) virus of swine origin (S-OIV). We analyzed the role of their pulmonary images in predicting the severity and diagnosis of the disease.MethodsAmong 97 patients with confirmed novel H1N1 infection, 42 patients treated with mechanical ventilation formed group 1, and the remaining 55 patients constituted group 2. The initial and subsequent radiograhic findings in groups 1 and 2 were compared with respect to the pattern, distribution, and extent of the abnormality.ResultsIn group 1, 24 patients presented with three or more lung zone diseases, whereas only 5 patients in group 2 demonstrated these findings (P<0.001). A pneumomediastinum or pneumothorax was observed in 24/42 patients in group 1 and in 18/55 patients in group 2 (P=0.019). Twelve patients in group 1 and 5 in group 2 developed a ground-glass opacity cyst with a honeycomb appearance (P=0.007).ConclusionsThe most common radiographic and computed tomography findings in children who were severely infected with S-OIV included unilateral or bilateral ground-glass opacities with or without associated focal or multifocal areas of consolidation. Children with bilateral involvement or with greater opacity on the chest radiographs were more likely to worsen and require the mechanical ventilation.

H1N1 pneumonia: our experience in 50 patients with a severe clinical course of novel swine-origin influenza A (H1N1) virus (S-OIV).

PurposeThe authors reviewed chest radiographs (CXR) and thin-section computed tomography (CT) findings of pulmonary complications in a selected population of 50 consecutive patients with severe novel swine-origin influenza A (H1N1) virus (S-OIV) pneumonia who were seen at the Subintensive Respiratory Unit (UTSIR) and at the Intensive Care Unit (ICU) at Monaldi Hospital, Naples, Italy.Materials and methodsCXR and CT findings of 50 patients who fulfilled the World Health Organisation (WHO) criteria for S-OIV infection were reviewed by four radiologists. The final study group of 50 patients was divided into two subgroups on the basis of clinical course: group 1 consisted of 42 patients requiring noninvasive mechanical ventilation and admitted to the UTSIR; group 2 consisted of eight patients who required ICU admission and extracorporeal membrane oxygenation or advanced mechanical ventilation from October 2009 to December 2009. All patients underwent CXR and thinsection multidetector CT (MDCT) scan; the initial and follow-up radiographs and CT scans were evaluated for the presentation and follow-up pattern (consolidation, groundglass opacities, nodules, reticulation), distribution and extent of abnormality.ResultsAll patients had radiological signs of pulmonary involvement. Ground-glass opacity and consolidation, which was mainly peripheral, was the most frequent finding. In three patients, we report for the first time in viral pneumonia the reversed halo sign. Lesion extent was related to aggressiveness of the illness. More often, both lungs were involved (82%). Thoracic comorbidity was present in 18% of patients; 22% of patients was obese, and in this group, the clinical course was more aggressive than in the others with the same lesion extent at imaging. Furthermore, superinfection led to worsening of the clinical conditions.ConclusionsThe most common CXR and CT findings in patients with S-OIV infection were unilateral or bilateral ground-glass opacities with or without associated focal or multifocal areas of consolidation. On MDCT, ground-glass opacities and areas of consolidation had a predominant peribronchovascular and subpleural distribution, resembling organising pneumonia; they progressed to bilateral extensive airspace disease in severely ill patients.

Pneumonia in novel swine-origin influenza A (H1N1) virus infection: High-resolution CT findings

Objective The purpose of our study was to review the initial high-resolution CT (HRCT) findings in pneumonia patients with presumed/laboratory-confirmed novel swine-origin influenza A (H1N1) virus (S-OIV) infection and detect pneumonia earlier. Materials and methods High-resolution CT (HRCT) findings of 106 patients with presumed/laboratory-confirmed novel S-OIV (H1N1) infection were reviewed. The 106 patients were divided into two groups according to the serious condition of the diseases. The pattern (consolidation, ground-glass, nodules, and reticulation), distribution, and extent of abnormality on the HRCT were evaluated in both groups. The dates of the onset of symptoms of the patients were recorded. Results The predominant CT findings in the patients at presentation were unilateral or bilateral multifocal asymmetric ground-glass opacities alone ( n = 29, 27.4%), with unilateral or bilateral consolidation ( n = 50, 47.2%). The consolidation had peribronchovascular and subpleural predominance. The areas of consolidation were found mainly in the posterior, middle and lower regions of the lungs. Reticular opacities were found in 6 cases of the initial MDCT scan. The extent of disease was greater in group 1 patients requiring advanced mechanical ventilation, with diffuse involvement in 19 patients (63.3%) of group 1 patients, and only 15/76 (19.7%) of group 2 patients ( p < 0.01, χ 2 test). 20 cases (19%) of the 106 patients had small bilateral or unilateral pleural effusions. None had evidence of hilar or mediastinal lymph node enlargement on CT performed at admission or later. Conclusions The most common radiographic and CT findings in patients with S-OIV infection are unilateral or bilateral ground-glass opacities with or without associated focal or multifocal areas of consolidation. On HRCT, the ground-glass opacities had a predominant peribronchovascular and subpleural distribution. CT plays an important role in the early recognition of severe S-OIV (H1N1).

Image Findings of Patients with H1N1 Virus Pneumonia and Acute Respiratory Failure

The aim of this study was to assess the findings of chest radiography and high-resolution computed tomography in patients requiring intensive care unit treatment for severe H1N1 virus pneumonia. In 2009, 10 patients required treatment in an intensive care unit for confirmed H1N1 pneumonia. All patients underwent chest radiography and high-resolution computed tomography. All 10 patients required mechanical ventilation because of respiratory failure. Nine patients presented with severe acute respiratory distress syndrome, and one patient died. Four patients underwent extracorporeal membrane oxygenation (ECMO) therapy. The results of chest radiography and high-resolution computed tomographic scans of these patients were systematically analyzed. The mean age of all patients was 44.1 +/- 12.3 years. All 10 patients showed abnormal results on chest radiography. The radiographic abnormalities were bilateral and multifocal in 10 patients. The predominant radiographic findings were consolidations (n = 9), ground-glass opacities (n = 8), and reticular opacities (n = 2). The most frequent computed tomographic findings at presentation consisted of bilateral ground-glass opacities (n = 9), pleural effusion (n = 9), areas of consolidation (n = 8), interstitial marking (n = 8), and crazy paving (n = 4). All patients undergoing ECMO therapy showed extensive bilateral ground-glass opacities, multifocal areas of consolidation, and crazy paving. Pleural effusion was present in three of four patients undergoing ECMO therapy. Patients requiring treatment in an intensive care unit for severe H1N1 pneumonia are at high risk for developing acute respiratory distress syndrome and frequently require ECMO therapy.

CT manifestations of patients with swine-origin influenza A H1N1 QI

Objective To explore the manifestations of chest multi-slice spiral CT in patients with initial infection of swine-origin influenza A (H1N1) virus (S-OIV). Methods The chest multi-slices spirals CT images of 19 firstly diagnosed patients with swine-origin influenza A (H1N1) in our institution were retrospectively studied. CT manifestations were evaluated by three experienced radiologists. Location, appearance of lung abnormalities, abnormal distribution, pleural effusion and others (pericadiaum, lymphadenopathy and pleural thickening) were observed and quantitatively analyzed. The correlation of ground-glass and consolidation CT scores with the fever time was studied. Results The abnormal CT findings were observed bilaterally in 18 of 19 subjects including ground-glass (n= 3), consolidation (n=3 ), consolidation accompanied with ground-glass (n=12). Most of these lesions were distributed diffusively (n=14) while the others located in the middle and low lobes (n= 4). Unilateral (n=3) or bilateral (n=2) pleural effusion were observed. Lymphadenopathy (n=2), effusion of pericadium (n=1), pleural thickening (n=1) and cardiac enlargement (n=2) were also found in patients with H1N1. CT scores of ground-glass were 4. 25(n=2),3.75 (n=1),2.25(n=1),1.75(n=1),1.00(n=6),0.75(n=2), 0.50(n=2),0(n=4).CT scores of consolidation were4.25(n=1),4.00(n=1),3.75 (n=1), 2.75(n=1),1.25(n=3),1.00(n=2),0.75(n=2),0.50(n=1),0.25(n=3),0(n=4). CT scores of ground-glass were significantly correlated with the fever time (r= 0.776, P 0.01). Conclusions The most common CT findings in patients with S-OIV infection are diffuse distribution of bilateral ground-glass opacities with or without associated focal or multifocal areas of consolidation. The increasing of ground-glass's range could be the marker of progression of H1N1 pulmonary infection at initial stage. Key words: Influenza,human; Pneumonia,viral; Tomography, X-ray computed

Swine-Origin Influenza A (H1N1) Viral Infection in Children: Initial Chest Radiographic Findings

To evaluate initial chest radiographic findings of swine-origin influenza A (S-OIV) (also known as H1N1) viral infection in children. This was an institutional review board-approved, HIPAA-compliant retrospective study of 108 patients who had microbiologically confirmed S-OIV infection and available initial chest radiographs obtained between April 2009 and October 2009. The final study group was divided on the basis of clinical course (group 1, outpatients without hospitalization [n = 72]; group 2, inpatients with brief hospitalization [n = 22]; group 3, inpatients with intensive care unit admission [n = 14]). Two pediatric radiologists blinded to patient group and lung parenchymal, airway, pleural, hilar, and mediastinal abnormalities systematically reviewed initial chest radiographs. Lung parenchyma and airways were evaluated for pattern (peribronchial markings, consolidation, and ground-glass, nodular, and reticular opacity), distribution, and extent of abnormalities. Radiographs were assessed for presence of pleural effusions or lymphadenopathy. Medical records were reviewed for underlying medical conditions and patient outcomes. Association between frequency of underlying medical conditions and clinical course of S-OIV infection among study groups was evaluated with the Pearson chi(2) test. The frequency of normal chest radiographs was significantly higher in group 1 (n = 48) than in groups 2 (n = 1) and 3 (n = 0) (P < .001, Pearson chi(2) test). Among patients with abnormal radiographs, the most common finding in group 1 was prominent peribronchial markings with hyperinflation (n = 17), whereas the most common findings in groups 2 (n = 12) and 3 (n = 12) were bilateral, symmetric, and multifocal areas of consolidation, often associated with ground-glass opacities. Nodular opacities, reticular opacities, pleural effusion, or lymphadenopathy were not observed in any patient. An increased frequency of underlying medical conditions was observed in patients with greater severity of illness due to S-OIV infection (group 3, 71%; group 2, 59%; group 1, 31%) (P = .003, Pearson chi(2) test). All 84 patients with available follow-up information have fully recuperated from S-OIV infection. Initial chest radiographs in children with a mild and self-limited clinical course of S-OIV infection are often normal, but they may demonstrate prominent peribronchial markings with hyperinflation. Bilateral, symmetric, and multifocal areas of consolidation, often associated with ground-glass opacities, are the predominant radiographic findings in pediatric patients with a more severe clinical course of S-OIV infection. (c) RSNA, 2009.

Swine-Origin Influenza A (H1N1) Viral Infection: Radiographic and CT Findings

The objective of our study was to review the chest radiographic and CT findings in patients with swine-origin influenza A (H1N1) virus (S-OIV) infection. The most common radiographic and CT findings in seven patients with S-OIV infection are unilateral or bilateral ground-glass opacities with or without associated focal or multifocal areas of consolidation. On MDCT, the ground-glass opacities and areas of consolidation had a predominant peribronchovascular and subpleural distribution, resembling organizing pneumonia.

High-resolution CT findings of respiratory syncytial virus pneumonia after bone marrow transplantation.

The aim of this study was to describe the high-resolution CT findings of respiratory syncytial virus pneumonia in 20 patients who had undergone allogeneic bone marrow transplantation. The study included 20 consecutive patients who developed respiratory syncytial virus pneumonia after bone marrow transplantation and who had high-resolution CT of the chest performed within 24 hr after the onset of symptoms. The CT scans were reviewed by two chest radiologists who assessed the pattern and distribution of findings. Bone marrow transplantation was performed on 12 male and eight female patients ranging from 3 to 48 years old (mean age, 25 years) for treatment of various forms of leukemia (n = 12), severe aplastic anemia (n = 6), Fanconi's syndrome (n = 1), and paroxysmal nocturnal hemoglobinuria (n = 1). Sixteen patients (80%) had abnormal CT findings. The predominant patterns of abnormality on high-resolution CT scans were small centrilobular nodules (10/20, 50%), air-space consolidation (7/20, 35%), ground-glass opacities (6/20, 30%), and bronchial wall thickening (6/20, 30%). The abnormalities were distributed in the central and peripheral areas of the lungs in nine cases, only in the periphery in five cases, and only in the central regions in two cases. The abnormalities were bilateral and asymmetric in distribution in 13 patients, bilateral and symmetric in two patients, and unilateral in one patient. The most common high-resolution CT findings in patients with respiratory syncytial virus pneumonia after bone marrow transplantation consist of small centrilobular nodules and multifocal areas of consolidation and ground-glass opacities in a bilateral asymmetric distribution.

Approach to the diagnosis of pulmonary disease in patients infected with the human immunodeficiency virus.

Patients infected with the human immunodeficiency virus are predisposed to develop a variety of common and uncommon infectious and neoplastic pulmonary diseases. Clinical information that can stratify the risk of occurrence of these pulmonary conditions includes: 1) CD4 cell count-the most important determinant; 2) concurrent antimicrobial therapy; 3) prior travel history; 4) known latent infections that may reactivate: and 5) underlying respiratory disease. Specific pulmonary diseases are discussed including: bacterial pneumonia, bronchitis, mycobacterial and fungal infections, pneumocystis carinii pneumonia, toxoplasmosis, cytomegalovirus, Kaposi sarcoma, lymphoma, and lung cancer. A differential diagnosis can be generated based on the chest radiographic pattern. Focal or multifocal areas of consolidation usually represent conventional bacterial pneumonia or, less commonly, tuberculosis. In severely immunocompromised patients, unusual diseases causing consolidation should be considered including: Rhodococcus infection, nocardiosis, cryptococcosis, aspergillosis, and lymphoma. Nodules can be present in tuberculosis, histoplasmosis, cryptococcosis, and Kaposi sarcoma. Interstitial opacities are common in pneumocystis carinii pneumonia, histoplasmosis, and cytomegalovirus pneumonia. Cavitation and cysts are features of pneumocystis carinii pneumonia, tuberculosis, aspergillosis, and lung cancer. Disease of the airways is increasingly recognized in those with acquired immunodeficiency syndrome. Lymphadenopathy is most common in mycobacterial infection, but can be a feature of fungal infection, lymphoma, Kaposi sarcoma, and lung cancer. The combined use of clinical information, knowledge of typical conditions associated with the human immunodeficiency syndrome, and radiographic patterns offers a useful approach to the diagnosis of pulmonary disease in the patient with the human immunodeficiency virus.

Computed Tomography in Established Adult Respiratory Distress Syndrome: Correlation With Lung Injury Score

To identify serial changes in the appearances of the lungs on computed tomography (CT) in patients with established adult respiratory distress syndrome (ARDS). Second, to evaluate any relationship between the extent of morphologic abnormalities on CT anatomic and physiologic derangement using a numeric score of the severity of lung injury. Retrospective, descriptive. Adult intensive care unit, Department of Radiology, and outpatient department of a national tertiary referral center. Eight patients meeting diagnostic criteria for ARDS able to tolerate CT scanning during the acute phase of their illness and who survived to be reevaluated during convalescence. Mechanical ventilatory support. Conventional intensive care support of other failed systems a appropriate. Thin-section CT scans of the lungs categorized as to extent (calculated percent volume of abnormal lung), distribution, and dominant disease pattern. Concurrent lung injury score (LIS) was recorded at the time of the CT during the acute phase of illness (mean, 26 days; range, 3 to 48 days after precipitating event) and at follow-up (96; 17 to 187 days). On initial CT scans, disease patterns included ground-glass opacification (8/8), parenchymal distortion (8/8), multifocal areas of consolidation (6/8), reticular opacities (6/8), and linear opacities (5/8). On follow-up scans, there was clearing of consolidation in all patients, but ground-glass opacification persisted in four of eight patients. The reticular pattern persisted unchanged in five of eight patients, became more extensive in two of eight, and developed in one. A reticular pattern was most pronounced in areas that had been densely consolidated previously. Evidence of parenchymal distortion, present on the initial scan in all patients, persisted in six of eight patients. Computed tomographic features suggestive of emphysema developed in one patient. The LIS revealed moderate to severe ARDS in all patients initially; this decreased to a mild or zero LIS at follow-up. Overall, there was 76.9% +/- 5.3% abnormal lung on the initial CT scan and 34.5 +/- 9.3% on the follow-up CT scan. There was a significant correlation between the extent of abnormalities on CT and LIS (r = 0.75, p < 0.01). The CT appearances of patients with ARDS who survive are variable and relate to the pattern of disease in the acute phase. Furthermore, the extent of CT abnormalities correlates strongly with LIS in both the acute phase and at follow-up.

Pathogenesis of bovine respiratory syncytial virus in experimentally infected lambs

Twenty-four 6–8-week-old conventionally reared lambs were inoculated intranasally and intratracheally with bovine respiratory syncytial virus. Infected lambs showed mild clinical signs characterized by slight serous nasal discharge, coughing, lachrymation and bronchovasicular sounds on the middle part of the lung 5–9 days post-inoculation (PI). Virus was isolated in nasal swabs from 9 of 24 lambs between 3 and 7 days PI. However, virus was recovered from tracheal and lung tissue of all lambs killed between 3 and 11 days PI. Virus-specific antibodies appeared as early 6 days PI but high titres were attained 14–21 days PI. Lungs of lambs killed on different days PI had multifocal areas of consolidation. There was an increase of lymphocytes with a T-suppressor cell marker and a decrease in those with a T-helper marker in lung lavages obtained 5 days PI.

Experimental parainfluenza type 3 infection in young lambs: clinical, microbiological, and serological response

Five, 1-week-old, colostrum-deprived lambs were inoculated transtracheally with a parainfluenza type-3 (PI-3) virus that had been isolated from a pneumonic lamb lung. A biphasic febrile response, cough, rapid breathing followed by forced expirations, listlessness, and anorexia were observed in the lambs. There were multifocal areas of consolidation in the lungs of all lambs and ulcerations in the nasal mucosa of three lambs. Serum antibody titers to PI-3 virus ranged from 2 to 16 in lambs necropsied Day 3 to Day 7 post-inoculation, respectively. Virus was isolated from nasal secretions, tracheal fluids, and lung tissues of all lambs.