Pulmonary alveolar proteinosis

Pulmonary alveolar proteinosis is a rare cause of respiratory distress in neonates. We present a 4 month old infant who presented with progressive respiratory distress since birth and failure to thrive. He was initially treated as a case of diffuse alveolar disease but on open lung biopsy was diagnosed as pulmonary alveolar proteinosis. The child expired at 7 months of age.

[Abnormalities in high-resolution computed tomography of the lungs in patients with idiopathic pulmonary arterial hypertension -- correlation with hemodynamic parameters and prognostic significance]

INTRODUCTION

The risk stratification in idiopathic pulmonary arterial hypertension (IPAH) patients is currently based on haemodynamic and functional parameters as well as serum biomarker concentrations. Until now the importance of changes appearing in high-resolution computed tomography (HRCT) of the lungs of patients with IPAH has not been investigated.

MATERIAL AND METHODS

Lung HRCT scans were analysed retrospectively in 48 IPAH patients (patients): 37 women, 11 men, mean age 41 +/- 15 years.

RESULTS

Focal ground-glass opacifications (FGG) were found in 12 patients (25%), and centrilobular nodules (CN) were found in 8 patients (17%). In the remaining 58% of patients HRCT revealed no changes (N). Significantly lower stroke volume was found in the CN group (41.0 +/- 8.5 ml) compared to 60.8 +/- 15.1 ml in the FGG group and 58.1 +/- 18.0 ml in the N group (p = 0.03). Right atrial pressure was significantly higher in the CN group (12.2 +/- 4.86 mm Hg) than in the FGG group (6.9 +/- 3.9 mm Hg) and the N group (7.6 +/- 5.3 mm Hg), p = 0.047. The presence of nodules was combined with considerably increased risk of death, both in univariate analysis (HR 5.35, 95% CI: 1.16-24.7, p = 0.03) and in multivariate analysis (HR 6.98, 95% CI: 1.41-34.59, p = 0.02). Ground-glass opacifications correlated neither with haemodynamic nor functional indexes, and were of no prognostic significance.

CONCLUSIONS

The presence of centrilobular nodules in lung HRCT scans of IPAH patients was combined with more severe haemodynamic compromise and was an independent negative prognostic indicator.

[Pulmonary alveolar microlithiasis: report of four cases]

INTRODUCTION

Pulmonary alveolar microlithiasis is a rare disease characterised by the formation and deposition of calcium phosphate microliths in the lung. It is an autosomal recessive disorder, for which mutation in the SLC34A2 gene was recently found to be responsible for the disease.

OBSERVATIONS

We report on four cases of pulmonary alveolar microlithiasis. Three patients were asymptomatic. The diagnosis was made after histological confirmation in three patients. The outcome was marked by the death of one patient.

CONCLUSION

Pulmonary alveolar microlithiasis is a rare disease. Diagnosis is made with high-resolution computed tomography, which exhibits the calcic character and distribution of the lesions, thus avoiding the need to perform lung biopsy. We suggest that a literature review be performed.

Finite element 3D reconstruction of the pulmonary acinus imaged by synchrotron X-ray tomography

The alveolated structure of the pulmonary acinus plays a vital role in gas exchange function. Three-dimensional (3D) analysis of the parenchymal region is fundamental to understanding this structure-function relationship, but only a limited number of attempts have been conducted in the past because of technical limitations. In this study, we developed a new image processing methodology based on finite element (FE) analysis for accurate 3D structural reconstruction of the gas exchange regions of the lung. Stereologically well characterized rat lung samples (Pediatr Res 53: 72-80, 2003) were imaged using high-resolution synchrotron radiation-based X-ray tomographic microscopy. A stack of 1,024 images (each slice: 1024 x 1024 pixels) with resolution of 1.4 mum(3) per voxel were generated. For the development of FE algorithm, regions of interest (ROI), containing approximately 7.5 million voxels, were further extracted as a working subunit. 3D FEs were created overlaying the voxel map using a grid-based hexahedral algorithm. A proper threshold value for appropriate segmentation was iteratively determined to match the calculated volume density of tissue to the stereologically determined value (Pediatr Res 53: 72-80, 2003). The resulting 3D FEs are ready to be used for 3D structural analysis as well as for subsequent FE computational analyses like fluid dynamics and skeletonization.

[Alveolar microlithiasis: an uncommon cause of the crazy paving pattern]

Alveolar microlithiasis is an uncommon disease of unknown etiology characterized by the presence of multiple, predominantly subpleural, intra-alveolar microcalcifications. We present a case in which the high-resolution CT images show diffuse pulmonary microcalcifications together with patchy areas of ground glass attenuation associated to marked thickening of the interlobular septa, all of which taken together constitute the crazy paving pattern. This pattern is not specific for alveolar microlithiasis; it has also been reported in other entities, including alveolar proteinosis, lipoid pneumonia, and bronchial alveolar carcinoma.

Detection of sonographic B-lines in patients with normal lung or radiographic alveolar consolidation

BACKGROUND

Diffuse comet-tail B-line artifacts in lung ultrasound are a sign of alveolar-interstitial syndrome, but isolated transthoracic scans positive for B-lines (multiple B lines or B+) could be detected in other conditions. The aim was to assess the prevalence and distribution of this sonographic sign in patients with normal lung or isolated alveolar consolidation in chest radiography.

MATERIAL/METHODS

Two hundred seventeen patients consecutively admitted to this emergency medicine unit with any diagnosis and without radiographic or clinical evidence of diffuse interstitial syndrome were analyzed. Each patient underwent chest radiography and lung sonographic examination with four anterolateral chest scans per side.

RESULTS

Of the 1736 sonographic scans performed, 13.2% were positive for the B+ pattern. Positive scans significantly corresponded to laterobasal areas or radiographic opacities due to lung alveolar consolidations (p<0.005). Twenty percent of the laterobasal scans of 145 patients with radiologically normal lung were positive. The negative predictive value of B+ was 83.9% (95% confidence interval: 78.2-89.7%), with a specificity of 90.3% (95%CI: 85.5-95.1%) for predicting any localized radiographic pulmonary opacity.

CONCLUSIONS

B+ scans can be detected in the chest areas surrounding an isolated alveolar consolidation and in the laterobasal scans of a radiographic normal lung. These features should always be considered when lung ultrasound is performed to rule out the alveolar-interstitial syndrome in an emergency setting. Moreover, B+ patterns have a satisfactory negative predictive value for radiographic lung opacities, which could have added diagnostic value in the ED evaluation of dyspneic patients.

Pulmonary alveolar microlithiasis in siblings

We report two cases of pulmonary alveolar microlithiasis (PAM) in siblings. The male child was diagnosed initially and family screening led to the diagnosis of the asymptomatic sister. The diagnosis was confirmed by high resolution computed tomography (HRCT) and bone scintigraphy which demonstrated the calcific nature of the lesions. We emphasize the importance of family screening of PAM index cases to detect the disease in the early, asymptomatic stage.

FDG-PET/CT finding of high uptake in pulmonary alveolar microlithiasis

Pulmonary alveolar microlithiasis (PAM) is a rare lung disease characterized by progressive intra-alveolar calcification. We present a case of PAM with abnormal accumulation of 18F-fluorodeoxyglucose (FDG) in both lungs. A 55-year-old man was referred to our hospital for progressive dyspnea. He had been diagnosed with PAM 25 years earlier by transbronchial lung biopsy. High-resolution computed tomography revealed multiple dense calcifications with little aerated lung. Combined positron emission tomography and computed tomography using 18F-FDG (FDG-PET/CT) showed the abnormal accumulation of FDG in both lungs with a maximal standardized uptake value of 7.3. High FDG uptake was observed mainly in the lung regions showing sparing calcification. The patient died of respiratory failure a month later and an autopsy revealed no significant inflammatory changes in either lung. We suspect that the markedly enhanced pulmonary FDG uptake may have some relation to the pathophysiology of PAM.

Pulmonary alveolar microlithiasis in a patient with rheumatic valvular heart disease

Pulmonary alveolar microlithiasis is a rare disease characterized by widespread intra-alveolar calcification of both lungs that is asymptomatic in the early stages. The disease typically follows a protracted course, and death can occur in 5 to 41 years after the initial diagnosis. Rheumatic fever is a multisystemic inflammatory disease that afflicts the child and juvenile population, and it is still very common in developing countries. Valve failure is the condition most linked to increased morbidity and mortality rates in this population and is the most severe complication of rheumatic fever, with consequent onset of chronic heart valve disease. We present a case of a female patient with a potential diagnosis of pulmonary alveolar microlithiasis with concurrent rheumatic valvular disease.

Wegener's granulomatosis presenting with diffuse alveolar hemorrhage and negative antineutrophilic cytoplasmic antibody test

One of the causes of diffuse pulmonary infiltrates can be blood from diffuse alveolar hemorrhage. Other causes include malignancy, edema fluid, infections, and protein (blood, pus, water, cells, or protein). Autoimmune vasculitis, such as Wegener's granulomatosis, should be considered in the setting of diffuse pulmonary infiltrates, anemia, systemic symptoms, and recurrence despite antibiotic therapy. Antineutrophilic cytoplasmic antibody testing can be useful but is not always diagnostic. Early tissue biopsy should be considered to guide therapy. We present a case of Wegener's granulomatosis that presented with diffuse alveolar hemorrhage. Diagnosis was made through renal biopsy; however, antineutrophilic cytoplasmic antibody testing was negative. A brief overview of pulmonary-renal vasculitides is also presented.

Inter-observer agreement in interpreting chest X-rays on children with acute lower respiratory tract infections and concurrent wheezing

CONTEXT AND OBJECTIVE

Many children with acute lower respiratory tract infections (ALRI) present to the emergency ward with concurrent wheezing. A chest x-ray is often requested to rule out pneumonia. We assessed inter-observer agreement in interpreting x-rays on such children. DESIGNS AND SETTING: Prospective consecutive case study at Instituto de Salud del Niño, Lima, Peru.

METHODS

Chest x-rays were obtained from eligible children younger than two years old with ALRI and concurrent wheezing who were seen in the emergency ward of a nationwide pediatric referral hospital. The x-rays were read independently by three different pediatric residents who were aware only that the children had a respiratory infection. All the children had received inhaled beta-adrenergic agonists before undergoing chest x-rays. Lobar and complicated pneumonia cases were excluded from the study.

RESULTS

Two hundred x-rays were read. The overall kappa index was 0.2. The highest individual kappa values for specific x-ray findings ranged from 0.26 to 0.34 for rib horizontalization and from 0.14 to 0.31 for alveolar infiltrate. Inter-observer variation was intermediate for alveolar infiltrate (kappa 0.14 to 0.21) and for air bronchogram (kappa 0.13 to 0.23). Reinforcement of the bronchovascular network (kappa 0.10 to 0.16) and air trapping (kappa 0.05 to 0.20) had the lowest agreement.

CONCLUSIONS

There was poor inter-observer agreement for chest x-ray interpretation on children with ALRI and concurrent wheezing seen at the emergency ward. This may preclude reliable diagnosing of pneumonia in settings where residents make management decisions regarding sick children. The effects of training on inter-observer variation need further studies.

Radiological findings of alveolar hydatid disease of the lung caused by Echinococcus multilocularis

Alveolar hydatid disease is a highly malignant form of echinococcosis caused by the larvae of the cestode Echinococcus multilocularis. Alveolar hydatid disease always affects the liver and can metastasise to the lungs and brain. The case reports describe the radiological features of alveolar hydatid disease of the lung caused by E. multilocularis. Multiple nodules which varied in size and shape were seen on CXR, CT showed most nodules to be lobulated, well circumscribed and of varying shape. Multiple lobulated lesions located between two segments of the lung and of varying shape appear to be characteristic of pulmonary alveolar hydatid disease caused by E. multilocularis.

Pulmonary involvement in Behçet's disease

BACKGROUND

Behçet's disease (BD) is a multisystem vasculitis and pulmonary involvement in BD is reported to indicate poor prognosis and high mortality.

OBJECTIVES

The aims of this study were to report on patients with pulmonary involvement and to discuss pulmonary artery thrombus and small-sized vasculitis associated with BD, with respect to previously published cases.

METHODS

Fifteen patients with BD and pulmonary involvement were included in this study. Massive hemoptysis was observed in all patients having pulmonary artery aneurysm (PAA).

RESULTS

Eleven patients had macroscopic pulmonary vascular disease (2 PAA, 3 PAA and thrombi and 6 only thrombi) and 3 patients had microscopic pulmonary vascular disease. The remaining patient had pulmonary cryptococcosis.

CONCLUSIONS

Data regarding treatment and outcomes of patients having BD-related pulmonary emboli/infarct and small-sized vasculitis are limited. Pulmonary vasculitis affects different levels of the pulmonary artery in BD and should be classified as macroscopic and microscopic vascular disease. 'Pulmonary artery thrombosis' should be used instead of 'pulmonary emboli'. Spiral CT angiography is the best radiological tool for evaluation of pulmonary problems in BD. Treatment of vasculitis should be based on the type of vascular disease and may vary among different types of vascular disease. Anticoagulation can be used in patients with microscopic vascular disease and nonaneurysmal macroscopic vascular disease. More studies are needed to clarify this issue.

Primary alveolar soft part sarcoma of the lung

Alveolar soft part sarcoma (ASPS) is a rare epithelial-like soft tissue sarcoma. The two main sites of its occurrence are the lower extremities in adults and the head and neck in children. Primary pulmonary involvement of this sarcoma, without evidence of soft tissue tumor elsewhere, is very exceptional. We present a case of primary ASPS of the lung in a 42-yr-old woman. A computed tomographic scan of the thorax demonstrated a well-circumscribed, solid tumor located in the right upper lobe. The mass was resected by right upper lobectomy. After 5 months, three metastatic lesions, involving lumbar vertebrae and occipital scalp, were found. Histologically, the tumor consisted of alveolar nests of large polygonal tumor cells, the cytoplasm of which frequently revealed periodic acid-Schiff-positive, diastase-resistant intracytoplasmic rod-like structures. On immunohistochemical staining, the tumor cells were positive only for vimentin and alpha-smooth muscle actin. Ultrastructural study using electron microscopy revealed characteristic electron-dense, rhomboid intracytoplasmic crystals.

A correlative study of ultrasound with serology in an area in China co-endemic for human alveolar and cystic echinococcosis

We correlated ultrasound (US) imaging classifications for human alveolar echinococcosis (AE) and cystic echinococcosis (CE) with serology (ELISA and immunoblotting (IB) incorporating native and recombinant/purified echinococcal antigens) in community surveys (2001-2003) and follow-up (2002 and 2003) of US-confirmed cases in Ningxia, China. One hundred and seventy-one cases (96 with AE, 75 with CE) were identified; of these, US classification and serological data were obtained for 142 and 112 cases, respectively. Seropositive-rates increased in CE patients with highly viable unilocular cyst lesions (Types CL, CE 1 or CE 2) to degenerating primary lesions (CE 3), but then decreased in subjects with inactive (CE 4) or dead (CE 5) cysts. In contrast, there was a constant increase in seropositivity from the early (P1, P2) to the advanced stages (P3, P4) with AE cases. For US-confirmed cases, follow-up by US combined with serology is invaluable for studying the clinical progression of echinococcosis and for detecting recurrent cysts or reinfection post-treatment.

Evaluation of two-way protein fluxes across the alveolo-capillary membrane by scintigraphy in rats: effect of lung inflation

Pulmonary microvascular and alveolar epithelial permeability were evaluated in vivo by scintigraphic imaging during lung distension. A zone of alveolar flooding was made by instilling a solution containing99mTc-albumin in a bronchus. Alveolar epithelial permeability was estimated from the rate at which this tracer left the lungs. Microvascular permeability was simultaneously estimated measuring the accumulation of111In-transferrin in lungs. Four levels of lung distension (corresponding to 15, 20, 25, and 30 cmH2O end-inspiratory airway pressure) were studied during mechanical ventilation. Computed tomography scans showed that the zone of alveolar flooding underwent the same distension as the contralateral lung during inflation with gas. Increasing lung tissue stretch by ventilation at high airway pressure immediately increased microvascular, but also alveolar epithelial, permeability to proteins. The same end-inspiratory pressure threshold (between 20 and 25 cmH2O) was observed for epithelial and endothelial permeability changes, which corresponded to a tidal volume between 13.7 ± 4.69 and 22.2 ± 2.12 ml/kg body wt. Whereas protein flux from plasma to alveolar space (111In-transferrin lung-to-heart ratio slope) was constant over 120 min, the rate at which99mTc-albumin left air spaces decreased with time. This pattern can be explained by changes in alveolar permeability with time or by a compartment model including an intermediate interstitial space.

Leflunomide-related acute interstitial pneumonia in two patients with rheumatoid arthritis: autopsy findings with a mosaic pattern of acute and organizing diffuse alveolar damage

We describe two cases of leflunomide-related interstitial pneumonia (IP). A 75-year-old woman with rheumatoid arthritis (RA) developed rapidly progressing IP 45 days after institution of leflunomide. She died of respiratory failure, and an autopsy revealed a mixed pattern of acute and organizing diffuse alveolar damage. A 69-year-old woman with RA also developed acute IP 3 months after institution of leflunomide. Methylprednisolone pulse therapy and cholestyramine ameliorated her IP. The implication of leflunomide in the pathogenesis of IP was suggested.

Acute and repeated inhalation lung injury by 3-methoxybutyl chloroformate in rats: CT-pathologic correlation

OBJECTIVES

To investigate the acute and repeated pulmonary damage in Sprague-Dawley rats caused by the inhalation of 3-methoxybutyl chloroformate (3-MBCF) using computed tomography (CT), and to correlate these results with those obtained from a pathological study.

METHODS

Sixty, 7-week-old rats were exposed to 3-MBCF vapor via inhalation (6 h/day) for 1 day (N=20), 3 days (N=20), and 28 days (5 days/week) (N=20) using whole body exposure chambers at a concentration of 0 (control), 3, 6 and 12 ppm. CT examinations including densitometry and histopathologic studies were carried out. For the follow-up study, the rats exposed for 3 days were scanned using CT and their pathology was examined at 7, 14, and 28 days.

RESULTS

There was a significant decrease in the parenchymal density in the groups exposed to the 3-MBCF vapors for 1 day at 3 ppm (p=0.022) or 6 ppm (p=0.010), compared with the control. The parenchymal density of the rats exposed to 12 ppm was significantly higher. The pathological findings in this period, the grades of vascular congestion, tracheobronchial exfoliation, and alveolar rupture were significant. In the groups exposed for 3 days, there was a large decrease in the parenchymal density with increasing dose (control: -675.48+/-32.82 HU, 3 ppm: -720.65+/-34.21 HU, 6 ppm: -756.41+/-41.68 HU, 12 ppm: -812.56+/-53.48 HU) (p=0.000). There were significant density differences between each dose in the groups exposed for 28 days (p=0.000). The CT findings include an irregular lung surface, areas of multifocal, wedge-shaped increased density, a heterogeneous lung density, bronchial dilatation, and axial peribronchovascular bundle thickening. The histopathology examination revealed the development of alveolar interstitial thickening and vasculitis, and an aggravation of the mainstem bronchial exudates and bronchial inflammation. The alveolar wall ruptures and bronchial dilatation became severe during this period. On the follow-up study, the groups exposed for 3 days showed diffusely increased parenchymal density on the 7 days study, but the lung densities were lower at 14 and 28 days than at 3 days. In the rats exposed to lowest concentration, the pulmonary parenchymal density and pathologic findings rapidly returned to normal within 1 week.

CONCLUSIONS

Decreased parenchymal density of the lung was a common CT finding in acute and repeated inhalation injury. The air accumulation is believed to be the results of tracheolaryngeal inflammatory edema, bronchial dilatation, and alveolar rupture from the early period.