[Radiological findings in lung transplantation]

Lung transplantation (single-lung transplantation, double-lung transplantation or heart-lung transplantation) may be the only effective therapy in end-stage pulmonary disease. At specialized institutions it has been performed on a routine basis for some years now. Diagnostic imaging plays an important role in the assessment of potential recipients as well as for the postoperative evaluation after transplantation. The aim of this review is to describe the role of imaging procedures of the chest in these patients and to demonstrate characteristic plain radiographic and computed tomographic findings. Normal postoperative findings specific to lung transplant patients as well as typical complications are presented. These include reimplantation response, acute and chronic rejection, and the typical bacterial, viral, and fungal infections as well as the sequelae of transbronchial biopsy.

Scintigraphic appearances in patients with pulmonary infection and lung scintigrams of intermediate or low probability for pulmonary embolism

Out of 294 patients with lung scintigrams of low or intermediate probability for pulmonary embolism, the appearances in 54 patients with a final diagnosis of pulmonary infection were reviewed. The most common finding was a matched defect in ventilation and perfusion occurring in 40 patients (76%). Regional reverse mismatch occurred in 13 patients (24%) and both appearances were found in one patient (2%). Reverse mismatch was also present in a further seven patients, four of whom had bronchial obstruction. Although occurring less frequently than matched defects, 81% of regional reverse mismatched defects were because of chest infection. The presence of regional reverse mismatch in patients investigated for pulmonary embolism suggests the alternative diagnosis of chest infection.

Chronic pulmonary disorders in sickle cell disease: findings at thin-section CT

PURPOSE

To characterize the non-acute abnormalities seen at computed tomography (CT) in patients with sickle cell (SC) disease and a prior history of acute chest syndrome (ACS)-pneumonia.

MATERIALS AND METHODS

Twenty-nine patients with SC disease who had experienced one to more than 10 (median, six) previous episodes of ACS-pneumonia were prospectively studied with thin-section CT of the thorax. Scans were graded for interstitial disease and assigned a disease index ranging from 0 to 3. Twenty-four patients underwent pulmonary function tests (PFTs) and measurement of their blood gasses.

RESULTS

Twelve of the 29 patients (41%) had significant interstitial disease that was multifocal. A correlation was found between the disease index and number of episodes of ACS-pneumonia (P = .02) but not between the disease index and PFT results.

CONCLUSION

Thin-section CT demonstrates significant multifocal interstitial lung abnormalities in 41% of selected patients with SC disease. The pattern is most consistent with scarring from episodes of infarction or infection.

Cholecyst-thoracic fistula. A rare complication of lithiasic cholecystitis

A 64-year-old male patient was studied for repeated right basal pneumonia of long duration. A computed tomography scan showed a cholecystitis of concealed evolution. Surgery revealed fistulization toward the thorax, with the passage of multiple calculi of a biliary origin to the chest cavity. We report the first described case to our knowledge of cholecyst-thoracic fistula secondary to cholecystitis of long evolution.

[Radiologic differential diagnosis of inflammatory round pulmonary infiltrates in immunocompromised patients. A prospective study using CT and MRT]

In a prospective study we examined the diagnostic ranking of CT and MR in 52 immunocompromised patients with nodular pulmonary lesions and clinical suspicion of invasive pulmonary aspergillosis (IPA). For early diagnosis of IPA (clinical symptoms having existed for less than 10 days) the CT halo sign proved highly sensitive and specific. MRT showed at this time a comparatively high sensitivity but only low specificity that could not be improved upon after Gd-DTPA. At a later stage of the aspergillosis infection (clinical symptoms manifested for more than 10 days) MR identified aspergillus-specific lesions with on-target characteristics (marked enhancement of margins after Gd-DTPA) or the so-called "reverse" target phenomenon (T2-weighted sequences). Such lesions were never seen in the early stage of the disease in patients with nodular pulmonary lesions of different aetiology (pseudomonal or staphylococcal pneumonia).

Differential ultrasonic diagnoses of pulmonary benign and malignant space-occupied lesions of the peripheral type

87 patients with pulmonary space-occupied lesions of the peripheral type which were either adhesive or close to pleura were examined using ultrasonography. Of them, 64 cases of lung cancers and 23 of benign lesions were then confirmed by histopathology. Five sonographic features, including configuration, echogenicity patterns, bronchial air phase in foci, margin, and pleural involvement, were significantly different between malignant and benign diseases (P < 0.01). The differential ultrasonography used in this series showed a sensitivity of 61% (14/23), a specificity of 95% (61/64), and an accuracy of 86% (75/87). The results of the study demonstrate that the ultrasonography is helpful in differentiating malignant and benign peripheral lung lesions near the plerua.

Clinical predictors of acute radiological pneumonia and hypoxaemia at high altitude

Fast breathing has been recommended as a predictor of childhood pneumonia. Children living at high altitude, however, may breathe faster in response to the lower oxygen partial pressure, which may change the accuracy of prediction of a high respiratory rate. To assess the usefulness of clinical manifestations in the diagnosis of radiological pneumonia or hypoxaemia, or both, at high altitude (2640 m above sea level), 200 children aged 7 days to 36 months presenting to an urban emergency room with cough lasting less than seven days were studied. Parents were interviewed and the children evaluated using standard forms. The results of chest radiographs and pulse oximetry obtained after clinical examination were interpreted blind. Radiological pneumonia and haemoglobin oxygen saturation < 88% were used as 'gold standards'. One hundred and thirty (65%) and 125 (63%) children had radiological pneumonia and hypoxaemia respectively. Crepitations and decreased breath sounds were statistically associated with pneumonia, and rapid breathing as perceived by the child's mother, chest retractions, nasal flaring, and crepitations with hypoxaemia. The best single predictor of the presence of pneumonia is a high respiratory rate, although the results are not as good as those reported by other studies. A respiratory rate > or = 50/minute had good sensitivity (76%) and specificity (71%) for hypoxaemia in infants. Hypoxaemia had a good sensitivity and specificity for pneumonia mainly in infants (83% and 73%, respectively). Logistic regression analysis showed that decreased or increased respiratory sounds and crepitations were associated with pneumonia, and that hypoxaemia is the best predictor when auscultatory findings are excluded. These results suggest that some clinical predictors appear to be less accurate in Bogota than in places at lower altitude, and that pulse oximetry can be used for predicting pneumonia.

[Findings of digital intensive or bed lung radiographs at the monitor vs. hard copy: a clinical ROC study]

45 bedside chest examinations acquired with storage phosphorus radiography, were displayed on a viewing box as single-format hard copies and at a high-performance digital reporting console. 6 observers performed an ROC study. For the pathologies under question, significantly better results were shown in monitor reporting due to pneumonic infiltration whereas no significant differences were found for pulmonary or mediastinal masses, or for pneumothoraces.

Localized reduction in 123I-MIBG accumulation in the lung

A patient with old myocardial infarction underwent 123I-MIBG scintigraphy to evaluate the adrenergic nerve system in the heart following the treatment of pneumonia. Decreased accumulation of MIBG was observed in the right lower lung field, corresponding to the area affected by pneumonia, as well as in the left ventricle with myocardial infarction. 99mTc-MAA lung perfusion scan demonstrated hypoperfusion in the region of reduced MIBG uptake. Regional decrease in MIBG uptake in the lung is considered to suggest lung pathology, and lung perfusion scan is recommended to discriminate selective endothelial damage from loss of vascular bed.

Invasive zygomycosis due to Conidiobolus incongruus

During the past decade, an increasing spectrum of pathogenic Zygomycetes fungi have caused infections in humans. The preponderance of these deeply invasive infections have been caused by members of the order Mucorales. However, deeply invasive zygomycoses due to genera of the order Entomophthorales (Conidiobolus species and Basidiobolus species) have seldom been reported. We describe a granulocytopenic patient with pulmonary and pericardial zygomycosis due to Conidiobolus incongruus, describe this organism's susceptibility to antifungal agents, characterize its diagnostic microbiological characteristics, and review previously reported cases of deeply invasive zygomycosis due to Conidiobolus species. In immunocompromised patients, C. incongruus is an uncommon but highly invasive fungal pathogen that may be resistant to amphotericin B and can be distinguished from other Zygomycetes fungi by characteristic mycological features.

A clinical profile of chronic bacterial pneumonia. Report of 115 cases

OBJECTIVE

To review the clinical presentation, radiology, microbiology, and response to therapy of patients with chronic bacterial pneumonia.

DESIGN

A retrospective analysis.

SETTING

An urban tertiary care medical center.

PARTICIPANTS

One hundred fifteen patients with pulmonary and/or constitutional symptoms of at least 1 month's duration with 4,000 or more colony-forming units (CFUs) of a single bacterial species identified by quantitative culture obtained via fiberoptic bronchoscopy.

MEASUREMENTS

Charts were analyzed for presence or absence of any predisposing illness, symptoms at presentation, roentgenographic abnormalities, microbiologic results, findings at fiberoptic bronchoscopy, and results of therapeutic intervention.

RESULTS

Sixty-five percent of patients with chronic bacterial pneumonia had a predisposing disease, 35 percent were "normal." Cough, fatigue, dyspnea, and weight loss were predominant symptoms in both groups. Bronchogenic carcinoma was newly diagnosed in 16 patients (14 percent). Haemophilus influenzae or alpha-hemolytic streptococcus was isolated in 68 percent of patients. Risk of recurrence of infection was inversely associated with duration of therapy in both groups.

CONCLUSIONS

Chronic bacterial pneumonia is more common than previously recognized. It occurs in patients with and without a predisposing illness. Clinical presentation, roentgenographic appearance, and bacteriology are similar between the two groups. Cure requires prolonged antibiotic therapy.

[Candida glabrata pneumonia in a non-immunosuppressed patient: diagnostic imaging with digital luminescence radiography and CT]

Pneumonias caused by Candida glabrata are extremely rare and occur almost exclusively in immunocompromised patients. We report an atypical case of Candida glabrata pneumonia in a non-immunocompromised patient and describe the imaging findings on digital radiography and computed tomography.

Radiologic assessment after lung transplantation

Imaging studies play a major role in patients undergoing lung transplantation. These patients are subject to unusual problems, such as the reimplantation response, acute rejection, bronchiolitis obliterans, ischemia-induced airway complications, and immuno-suppression-associated lymphoma. In addition, these patients are also subject to all of the usual problems associated with thoracic surgery, including atelectasis, infection, pneumothorax, and pleural effusion, all conditions for which radiologic assessment is crucial.

Helical computed tomography of the thorax. Clinical applications

Intuitively, any technique that minimizes the effects of respiratory motion, eliminates misregistration between scans, minimizes intravenous contrast requirements, and allows high quality multiplanar and 3-D image reconstruction is likely to have a tremendous impact on conventional notions concerning routine thoracic CT. Helical scanning is already of proved efficacy for vascular and airway imaging as well as for identifying and characterizing pulmonary nodules. It may be anticipated that the indications for the use of helical imaging will continue to expand. Of particular interest is the ongoing development of reconstruction algorithms that allow high-quality images to be obtained with rapid table incrementation while simultaneously reducing radiation exposure. Given the intrinsically high contrast of structures within the thorax coupled with the disadvantages that result from respiratory motion, it is not unreasonable to conclude that within the near future volumetric techniques will be the standard for nearly all CT applications within the thorax.

Ultrafast computed tomography of the chest

Improvements in scan speed and resolution are changing the role of the pulmonary imager. An understanding of airway mechanics and blood flow physiology is required to take full advantage of the new technology. Assessment of regional airflow and blood flow provides information that is currently unavailable from clinical tools.

Causes of fever and pulmonary densities in patients with clinical manifestations of ventilator-associated pneumonia

BACKGROUND

Ventilator-associated pneumonia, a leading cause of sepsis in patients with acute respiratory failure, is difficult to distinguish clinically from other processes affecting patients receiving mechanical ventilation. We conducted a prospective study of patients with suspected ventilator-associated pneumonia to identify the causes of fever and densities on chest radiographs and to evaluate the diagnostic yield and efficiency of tests used alone and in combination.

METHODS

The 50 patients entered into the study underwent a systematic diagnostic protocol designed to identify all potential causes of fever and pulmonary densities. Diagnoses responsible for fever were established by strict diagnostic criteria for 45 of the 50 patients. The prevalence of specific conditions and diagnostic yield of individual tests were used to formulate a simplified diagnostic protocol.

RESULTS

The diagnostic protocol identified 78 causes of fever (median 2 per patient). Infections were the leading causes of fever and pulmonary densities. Of the 45 patients with fever, 37 had one or more infections identified (67 sources). Most infections (84 percent) were one of four types:pneumonia, sinusitis, catheter-related infection, or urinary tract infection. Ventilator-associated pneumonia occurred in only 42 percent. All but nine infections (87 percent) were directly or indirectly related to insertion of a catheter or a tube. Concomitant infections were frequent (62 percent), particularly in patients with sinusitis (100 percent), catheter-related infections (93 percent), and pneumonia (74 percent). Of concomitant infections, 60 percent were caused by a different pathogen. Noninfectious causes of fever were more common in the 22 patients with adult respiratory distress syndrome. Histologically proved pulmonary fibroproliferation was the only cause of fever in 25 percent of patients with adult respiratory distress syndrome. Radiographic densities were caused by an infection in only 20 patients (19 pneumonia, 1 empyema). In more than 50 percent of the 25 patients without adult respiratory distress syndrome, congestive heart failure, and atelectasis were the sole causes of pulmonary densities, and fever always originated from an extrapulmonary site of infection. Used in combination, bronchoscopy with protected sampling, computed tomographic scan of the sinuses, and cultures of maxillary sinus aspirate, central intravenous or arterial lines, urine, and blood identified 58 of the 78 sources of fever (74 percent).

CONCLUSIONS

The observations in this study document the complex nature of acute respiratory failure and fever and underscore the need for accuracy in diagnosis. The frequent occurrence of multiple infectious and noninfectious processes justifies a systematic search for source of fever, using a comprehensive diagnostic protocol. A simplified diagnostic protocol was devised based on the diagnostic value of individual tests.

Bordetella bronchiseptica pneumonia in a patient with AIDS

Bordetella bronchiseptica is recognised as a respiratory tract pathogen in many mammalian species, but has rarely been implicated in human infection. A case is reported of pneumonia caused by B bronchiseptica in a patient suffering from acquired immunodeficiency syndrome (AIDS).

Cat-transmitted fatal pneumonic plague in a person who traveled from Colorado to Arizona

Plague, primarily a disease of rodents and their infected fleas, is fatal in 50% of infected humans if untreated. In the United States, human cases have been concentrated in the southwest. The most common modes of plague transmission are through flea bites or through contact with infected blood or tissues; however, primary pneumonic plague acquired from cats has become increasingly recognized. We report on the case investigation of a patient, presumably exposed to a plague-infected cat in Colorado, who presented with gastrointestinal symptoms, and subsequently died of primary pneumonic plague. Public health officials should be vigilant for plague activity in rodent populations, veterinarians should suspect feline plague in ill or deceased cats, and physicians should have a high index of suspicion for plague in any person who has traveled to plague enzootic areas.

Quinidine-induced reversible pneumonitis

We report a patient who developed fever and rapidly progressing lung infiltrates 4 days after the beginning of continuous quinidine sulfate therapy. The fever disappeared during the following 48 h and the pneumonitis slowly resolved over the next month once quinidine therapy was stopped. The diagnosis of quinidine-induced pneumonitis, which has not previously been reported in the literature (to our knowledge), was confirmed by means of a rechallenge with quinidine.

[Radiographic evaluation of the clinical course and outcome in acute pneumonias]

The authors review the data of x-ray functional examinations of 525 patients with acute parenchymatoys pneumonia, 393 convalescents after pneumonia 3-6 months after the disease and analyze 480 case histories of patients, hospitalized for acute pneumonia 10 years ago. Development, x-ray picture, and resolution of the process are described. Besides traditional x-ray examination, roentgenography in oblique projections and pulmonary sonography are recommended in order to specify the anatomic changes in the lungs. Functional peculiarities of the involved and intact lungs were studied. Altogether 92.4% of convalescents are discharged from hospital with changed pulmonary pattern and, rather often, with infiltration of the parenchyma in the subpieural portions of the involved lobes and segments, as well as with disordered respiratory function of the lungs. Unfavorable outcomes in remote period after disease (pneumosclerosis, pneumocirrhosis, emphysema, chronic pneumonia) are observed mainly in subjects discharged from hospital before complete clinical cure.

Risk factors for pneumonia among children in a Brazilian metropolitan area

OBJECTIVE

To investigate risk factors for pneumonia for infants < 2 years of age.

DESIGN

Hospital-based, case-control study with neighborhood control subjects.

SETTING

Urban area in southern Brazil.

SUBJECTS

Five hundred ten infants with radiologically confirmed pneumonia who were admitted to a pediatric hospital. One age-matched neighborhood control subject was selected for each case.

RESULTS

Multiple conditional regression modeling was used to control for confounding, taking into account the hierarchical relationships between risk factors. The incidence of radiologically confirmed pneumonia was associated with low paternal education, the number of persons in the household, young maternal age, attendance at day-care centers, low birth weight and weight-for-age, lack of breast-feeding and of non-milk supplements, and a history of previous pneumonia or wheezing. Day-care center attendance showed the highest risk, with an adjusted odds ratio of 11.75.

CONCLUSIONS

In addition to continued efforts toward appropriate case management, actions directed against the above risk factors may help prevent the major cause of deaths of children younger than 5 years.