Pulmonary talcosis: imaging findings

Spectrum of Thoracic Imaging Findings in the Setting of Substance Abuse

ABSTRACT

Substance abuse continues to be prevalent nationwide and can lead to a myriad of chest pathologies. Imaging findings are vast and can include nodules, masses, ground-glass opacities, airspace disease, and cysts. Radiologists with awareness of these manifestations can assist in early identification of disease in situations where information is unable to be obtained from the patient. This review focuses on thoracic imaging findings associated with various forms of substance abuse, which are organized by portal of entry into the thorax: inhalation, ingestion, and injection.

Combined Pulmonary Fibrosis and Emphysema in a Patient With Chronic Occupational Exposure to Trichloroethylene

Combined pulmonary fibrosis and emphysema (CPFE) is a clinical syndrome of upper-zone-predominant emphysema on high-resolution CT and a peripheral and basal-predominant diffuse pulmonary fibrosis. Multiple occupational and inhalational exposures have been associated with CPFE. We describe a U.S. veteran, who developed CPFE after a prolonged, intense exposure to trichloroethylene as an aircraft maintenance worker. We believe that this may be another example of occupational-associated CPFE.

"Skin Popping" and "Shooter's Patch" As Manifestations of Intradermal Drug Abuse

Talc, a common adulterant in injectable opioids and filler in oral tablets, is frequently abused as crushed suspensions in injections. This review aims to recognize intradermal drug injection referred to colloquially as "skin popping" or "shooter's patch" as a cause of granulomatous disease and prevention of systemic complications from cutaneous cues.

Pleurisy secondary to nonthrombotic pulmonary emboli in a patient with intravenous drug use

Patients with injection drug use can have nonthrombotic pulmonary emboli (NTPE) of foreign insoluble particles that are either parts of the equipment used or mixed with the drug as an additive. These foreign particles can become a nidus for infection and inflammation. We present a case of a 31-year-old man with active intravenous drug use who initially presented with signs and symptoms of pleurisy and was found to have NTPE of septic refractile crystalline material as seen on bronchial wash and brush biopsy. We believe our patient likely had embolism of either crack particles, needle fragments or cotton-wool fragments that led to a localized inflammatory reaction and infection. This highlights the importance of obtaining detailed history and diagnostic workup. Once the diagnoses of bacterial endocarditis and thrombophlebitis are ruled out with blood cultures, transthoracic echocardiogram, trans-esophageal echocardiogram and/or CT scan (depending on the suspicion), NTPE should be considered and bronchoscopy with bronchoalveolar lavage with biopsy should be performed.

Differential diagnosis of pulmonary sarcoidosis: a review

Diagnosing pulmonary sarcoidosis raises challenges due to both the absence of a specific diagnostic criterion and the varied presentations capable of mimicking many other conditions. The aim of this review is to help non-sarcoidosis experts establish optimal differential-diagnosis strategies tailored to each situation. Alternative granulomatous diseases that must be ruled out include infections (notably tuberculosis, nontuberculous mycobacterial infections, and histoplasmosis), chronic beryllium disease, hypersensitivity pneumonitis, granulomatous talcosis, drug-induced granulomatosis (notably due to TNF-a antagonists, immune checkpoint inhibitors, targeted therapies, and interferons), immune deficiencies, genetic disorders (Blau syndrome), Crohn's disease, granulomatosis with polyangiitis, eosinophilic granulomatosis with polyangiitis, and malignancy-associated granulomatosis. Ruling out lymphoproliferative disorders may also be very challenging before obtaining typical biopsy specimen. The first step is an assessment of epidemiological factors, notably the incidence of sarcoidosis and of alternative diagnoses; exposure to risk factors (e.g., infectious, occupational, and environmental agents); and exposure to drugs taken for therapeutic or recreational purposes. The clinical history, physical examination and, above all, chest computed tomography indicate which differential diagnoses are most likely, thereby guiding the choice of subsequent investigations (e.g., microbiological investigations, lymphocyte proliferation tests with metals, autoantibody assays, and genetic tests). The goal is to rule out all diagnoses other than sarcoidosis that are consistent with the clinical situation. Chest computed tomography findings, from common to rare and from typical to atypical, are described for sarcoidosis and the alternatives. The pathology of granulomas and associated lesions is discussed and diagnostically helpful stains specified. In some patients, the definite diagnosis may require the continuous gathering of information during follow-up. Diseases that often closely mimic sarcoidosis include chronic beryllium disease and drug-induced granulomatosis. Tuberculosis rarely resembles sarcoidosis but is a leading differential diagnosis in regions of high tuberculosis endemicity.

Combined Pulmonary Fibrosis and Emphysema: When Scylla and Charybdis Ally

Combined pulmonary fibrosis and emphysema (CPFE) is a recently recognized syndrome that, as its name indicates, involves the existence of both interstitial lung fibrosis and emphysema in one individual, and is often accompanied by pulmonary hypertension. This debilitating, progressive condition is most often encountered in males with an extensive smoking history, and is presented by dyspnea, preserved lung volumes, and contrastingly impaired gas exchange capacity. The diagnosis of the disease is based on computed tomography imaging, demonstrating the coexistence of emphysema and interstitial fibrosis in the lungs, which might be of various types and extents, in different areas of the lung and several relative positions to each other. CPFE bears high mortality and to date, specific and efficient treatment options do not exist. In this review, we will summarize current knowledge about the clinical attributes and manifestations of CPFE. Moreover, we will focus on pathophysiological and pathohistological lung phenomena and suspected etiological factors of this disease. Finally, since there is a paucity of preclinical research performed for this particular lung pathology, we will review existing animal studies and provide suggestions for the development of additional in vivo models of CPFE syndrome.

Medical Complications of Injection Drug Use - Part II

Medical Complications of Injection Drug Use - Part IIDuring the past 2 decades, the risk of death, as well as the prevalence of hospitalizations in the United States, has increased substantially among people who inject drugs, mainly because of the opioid epidemic. In Part Two of this two-part review, the authors review complications observed in people who inject drugs and strategies to reduce harm.

Syndrome of Combined Pulmonary Fibrosis and Emphysema: An Official ATS/ERS/JRS/ALAT Research Statement

Background: The presence of emphysema is relatively common in patients with fibrotic interstitial lung disease. This has been designated combined pulmonary fibrosis and emphysema (CPFE). The lack of consensus over definitions and diagnostic criteria has limited CPFE research. Goals: The objectives of this task force were to review the terminology, definition, characteristics, pathophysiology, and research priorities of CPFE and to explore whether CPFE is a syndrome. Methods: This research statement was developed by a committee including 19 pulmonologists, 5 radiologists, 3 pathologists, 2 methodologists, and 2 patient representatives. The final document was supported by a focused systematic review that identified and summarized all recent publications related to CPFE. Results: This task force identified that patients with CPFE are predominantly male, with a history of smoking, severe dyspnea, relatively preserved airflow rates and lung volumes on spirometry, severely impaired DlCO, exertional hypoxemia, frequent pulmonary hypertension, and a dismal prognosis. The committee proposes to identify CPFE as a syndrome, given the clustering of pulmonary fibrosis and emphysema, shared pathogenetic pathways, unique considerations related to disease progression, increased risk of complications (pulmonary hypertension, lung cancer, and/or mortality), and implications for clinical trial design. There are varying features of interstitial lung disease and emphysema in CPFE. The committee offers a research definition and classification criteria and proposes that studies on CPFE include a comprehensive description of radiologic and, when available, pathological patterns, including some recently described patterns such as smoking-related interstitial fibrosis. Conclusions: This statement delineates the syndrome of CPFE and highlights research priorities.

Combined Pulmonary Fibrosis and Emphysema and Digital Clubbing

Combined pulmonary fibrosis and emphysema (CPFE) is an underrecognized syndrome that involves simultaneous restrictive-obstructive lung disease. The prognosis is poor, and it frequently occurs with comorbidities. Heavy or former smoking is a major risk factor, and computed tomography (CT) typically shows lower zone fibrosis and upper zone emphysema. Chronic respiratory failure, pulmonary hypertension, and lung carcinoma are major causes of mortality. Diagnosis of CPFE should be combined with palliative care due to the high mortality of the condition, especially in the case of delayed diagnosis. We present the case of a 73-year-old male with a history of non-small cell lung cancer, 50 pack-year smoking, and cervical spine injury (CSI) with a late diagnosis of CPFE. After presenting to the emergency department for an acute exacerbation of dyspnea and hypoxia, he was initially treated with a congestive heart failure protocol. Further examination showed mixed pulmonary function tests as well as digital clubbing, and a CT scan showed changes indicative of advanced bullous emphysema diffusely throughout both lungs with an upper lobe predominance and basilar fibrosis. He was diagnosed with CPFE and immediately treated for both restrictive and obstructive lung diseases with supplemental oxygen, albuterol, ipratropium, corticosteroids, systemic antibiotics, as well as provided with palliative consultation. His previous history and CSI delayed diagnosis, as his lung restriction was likely assumed to be from impaired chest wall mobility rather than CPFE. This case highlights the presentation of a relatively rare disease that was confounded by comorbidities. 

Excipient lung disease in a patient taking the benzodiazepine derivative etizolam: A case report

Excipient Lung Disease is an inflammatory response to the intravenous administration of oral formulations of drugs and their excipients (additives). Previously described offenders include opioids and Ritalin, whose excipients, when crushed and administered intravenously, lead to inflammation and are demonstrated by centrilobular nodules and ground-glass formations on Chest Computed Tomography. In this case report, we demonstrate Chest CT findings of excipient lung disease in a patient using etizolam, a benzodiazepine derivative commonly used as an anxiolytic in Japan. Of note, the patient acquired etizolam for purchase through online retailers without prescription, which is becoming more common occurrence and offers the additional risk of unknown formulations.

Non-Infectious Granulomatous Lung Disease: Imaging Findings with Pathologic Correlation

Non-infectious granulomatous lung disease represents a diverse group of disorders characterized by pulmonary opacities associated with granulomatous inflammation, a relatively nonspecific finding commonly encountered by pathologists. Some lesions may present a diagnostic challenge because of nonspecific imaging features; however, recognition of the various imaging manifestations of these disorders in conjunction with patients' clinical history, such as age, symptom onset and duration, immune status, and presence of asthma or cutaneous lesions, is imperative for narrowing the differential diagnosis and determining appropriate management of this rare group of disorders. In this pictorial review, we describe the pathologic findings of various non-infectious granulomatous lung diseases as well as the radiologic features and high-resolution computed tomography imaging features.

Imaging diagnosis of classical and new pneumoconiosis: predominant reticular HRCT pattern

Our understanding of the manifestations of pneumoconioses is evolving in recent years. Associations between novel exposures and diffuse interstitial lung disease have been newly recognized. In advanced asbestosis, two types of fibrosis are seen, probably related to dose of exposure, existence of pleural fibrosis, and the host factor status of the individual. In pneumoconiosis of predominant reticular type, nodular opacities are often seen in the early phase. The nodular pattern is centrilobular, although some in metal lung show perilymphatic distribution, mimicking sarcoidosis. High-resolution computed tomography enables a more comprehensive correlation between the pathologic findings and clinically relevant imaging findings. The clinician must understand the spectrum of characteristic imaging features related to both known dust exposures and to historically recent new dust exposures.

Chest Imaging in the Diagnosis of Occupational Lung Diseases

Imaging plays a crucial role in the diagnosis and monitoring of occupational lung diseases (OLDs); however, the sensitivity and specificity of detection and diagnosis vary greatly depending on the imaging modality used. There is substantial overlap in appearance with non-occupation-related entities. OLDs should be considered in the differential even in the absence of a provided exposure history. Because many findings are not specific, a multidisciplinary approach is important in arriving at the diagnosis and will continue to be important as workplace-related pulmonary diseases evolve with changing industrial practices and workplace regulations.

A potential cause of asbestos-related granulomatosis due to adulterant contamination in a drug abuser

Drug adulterants containing contaminants have been known to cause lung disease by inhalation or intravenous intake. Talcosis due to intravenous talc injection has been widely described in the literature, whereas the hypothesis of granulomatosis due to asbestos related to adulterated cocaine injection has not yet been explored. Herein, a case of pulmonary granulomatosis due to asbestos fibres related to cocaine injection in a young woman is described. Inorganic material in the lung was first individuated by light microscopy and last was identified using the SEM-EDX method. This case is unique since the occupational and passive inhalation of asbestos was excluded with absolute certainty.

Intranasal Acetaminophen Abuse and Nasal, Pharyngeal, and Laryngotracheal Damage

A young adult female originally presented with necrosis of the nasal cavity mucosa and septum after sniffing crushed acetaminophen. She underwent endoscopic sinus surgery and debridement but continued to use acetaminophen intranasally. Four months later, the destruction had extended to include the posterior pharyngeal wall and subglottis. The diagnosis was confirmed by polarizable talc found on biopsy of the subglottis. While nasal insufflation of cocaine and hydrocodone-acetaminophen has been well-documented, intranasal abuse of exclusively acetaminophen is not well understood. This case demonstrates the destructive potential of intranasal acetaminophen use and may help physicians recognize unusual signs and symptoms of intranasal drug abuse.

Pulmonary foreign body granulomatosis in a chronic user of powder cocaine

We describe the case of a 33-year-old man, a chronic user of powder cocaine, who presented with dyspnea, fever, night sweats, and significant weight loss. Chest HRCT revealed centrilobular nodules, giving an initial impression of miliary tuberculosis. Therefore, he was started on an empirical, four-drug antituberculosis treatment regimen. Four weeks later, despite the tuberculosis treatment, he continued to have the same symptoms. We then performed transbronchial lung biopsy. Histopathological analysis of the biopsy sample revealed birefringent foreign body granuloma. A corroborative history of cocaine snorting, the presence of centrilobular nodules, and the foreign body-related histopathological findings led to a diagnosis of pulmonary foreign body granulomatosis. This report underscores the fact that pulmonary foreign body granulomatosis should be included in the differential diagnosis of clinical profiles resembling tuberculosis.

Beyond Pulmonary Embolism; Nonthrombotic Pulmonary Embolism as Diagnostic Challenges

Nonthrombotic pulmonary embolism (NTPE) is less well understood and is encountered less frequently than pulmonary embolism from venous thrombosis. NTPE results from embolization of nonthrombotic material to the pulmonary vasculature originating from many different cell types as well as nonbiologic or foreign materials. For many radiologists NTPE is a challenging diagnosis, presenting nonspecific or unusual imaging findings in the setting of few or unusual clinical signs. The aim of this paper is to review the pathophysiology of diverse causes of NTPE, which should aid radiologists to better understand and, more importantly, diagnose these infrequent events.

An Unusual and Fatal Cause of Miliary Nodules on Chest Radiography

Foreign body granulomatosis has many etiologies, including the injection of oral medications intravenously. The insoluble filler materials that are used in the medications can lodge in pulmonary arterioles and capillaries, which can trigger foreign body giant cell reaction, chronic inflammation, thrombosis, and fibrosis, resulting in pulmonary hypertension, progressive shortness of breath, and, potentially, fatal conditions. On imaging, this may present with multiple miliary mottling’s/nodules. The use of a bronchoscopy with biopsy can be an excellent way to establish a diagnosis in appropriate clinical settings. Here, we present a case of a 37-year-old old male found to have multiple miliary densities on imaging due to intravenous use of oral medication.

[Nonthrombotic pulmonary embolisms]

The term nonthrombotic pulmonary embolism (NTPE) is defined as embolization of pulmonary arteries caused by foreign bodies (e. g. detached catheter fragments), biological substances (e. g. septic thrombus) or exogenous substances (e. g. gas). The frequency of NTPE is underestimated. Symptoms can cover the spectrum from undetectable to sudden death. In addition to mechanical obstruction of the pulmonary arteries, some NTPEs trigger an inflammatory cascade that causes deterioration of vascular, pulmonary and cardiac function. Radiological imaging in combination with the medical history of patients is sufficient to identify most NTPEs with certainty. The aim of this article is to make readers aware of the symptoms, frequency, relevance, classification, pathophysiology, laboratory findings and radiological findings of the most frequent forms of NTPE. The spectrum of forms presented here includes pulmonary embolisms due to foreign bodies (intravascular, intracorporeal and extracorporeal), amniotic fluid, endogenous tissue, fat, tumors, septic thrombi, hydatids, cement, metallic mercury, gas, silicone and particles.

[Pulmonary intravascular talcosis: A case report]

INTRODUCTION

Pulmonary intravascular talcosis is a rare condition occurring in intravenous drug users injecting oral medications. Talc results in a foreign-body granulomatous reaction giving a radiological haematogenic miliary appearance mimicking miliary tuberculosis. Drug users represent a population at risk for both these conditions and their distinction may be challenging.

CASE REPORT

We reported the case of a man, 33 year-old, intravenous drug addict, detected by the health services because he was the partner of a person who died of contagious and multi-resistant tuberculosis. Chest X-ray and CT scan showed a typical miliary appearance. Despite negative microbiology, clinical diagnosis of miliary tuberculosis was retained. Due to the lack of radiological improvement despite appropriate antibiotic treatment, re-evaluation and trans-bronchial biopsy were undertaken. The presence of granulomas centered by birefringent foreign bodies in polarized light led to a diagnosis of pulmonary intravascular talcosis.

CONCLUSION

In the presence of pulmonary miliary in an intravenous drug addict, intravascular talcosis should be suspected.

Intranasal tissue necrosis associated with opioid abuse: Case report and systematic review

OBJECTIVE

Opioid abuse is a common disorder affecting over 2 million Americans. Intranasal tissue necrosis is a previously described sequela of nasal opioid inhalation, with a similar presentation to invasive fungal rhinosinusitis (IFRS). The goal of this case report and systematic review is to evaluate the evidence supporting this uncommon disease, with qualitative analysis of the presentation, management and treatment outcomes.

DATA SOURCES

MEDLINE, EMBASE, Google Scholar, Scopus, and Web of Science.

REVIEW METHODS

Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines were utilized to identify English-language studies reporting intranasal mucosal injury associated with prescription opioid abuse. Primary outcomes included clinical presentation, treatment strategies, and outcomes.

RESULTS

Systematic review identified 61 patients for qualitative analysis. Common clinical features include facial pain without a history of chronic sinusitis or known immunodeficiency. Diagnostic nasal endoscopy revealed superficial debris with underlying tissue necrosis, consistent with a preliminary diagnosis of IFRS. Characteristic pathologic findings include mucosal ulceration with an overlying acellular substrate, often with polarizable material. Fungal colonization is often reported, with several accounts of angiocentric invasion in immunocompetent patients. Complete symptom resolution is expected following surgical debridement with cessation of intranasal opioid inhalation, with 89% of identified patients experiencing a complete resolution of disease.

CONCLUSION

Intranasal opioid abuse is a prevalent condition associated with chronic pain and tissue necrosis that is clinically concerning for invasive fungal disease. Whereas IFRS must be excluded, even in patients without known immunodeficiency, complete resolution of symptoms can be expected following surgical debridement with cessation of opioid abuse. Laryngoscope, 1767-1771, 2018.

Cosmetic Talc-Related Pulmonary Granulomatosis

Inhalation of cosmetic talc can lead to pulmonary foreign-body granulomatosis, though fewer than 10 cases of inhaled cosmetic talc–related pulmonary granulomatosis have been reported in adults. We report the case of a 64-year-old man with diffuse, bilateral pulmonary nodules and ground glass opacities associated with chronic inhalation of cosmetic talc. Transbronchial biopsy showed peribronchiolar foreign-body granulomas. After cessation of talc exposure, the patient demonstrated clinical and radiographic improvement without the use of corticosteroids. This case demonstrates that a conservative approach with cessation of exposure alone, without the use of corticosteroids, can be an effective therapy in cosmetic talc–related pulmonary granulomatosis.

A Case of Acute Pericarditis Following Intravenous Injection of Crushed Morphine Tablets

A 37-year-old male presented with sharp, severe chest pain following seven days of intravenous injection of crushed morphine tablets. The chest pain was positional and pleuritic in nature and resolved with leaning forward. Work-up was notable for an ECG with inferior and anterolateral PR depressions as well as a CT chest with diffuse centrilobular nodules. Per radiology, the CT findings along with the patient's history were concerning for pulmonary granulomatosis from deposition of talc or some other foreign body. Cardiology was consulted and diagnosed the patient with acute pericarditis, given his typical symptoms and ECG changes. On review of the literature, pulmonary granulomatosis following intravenous injection of foreign bodies is well documented. There are numerous studies documenting foreign body deposition and granulomatosis in organs other than the lungs on post-mortem analyses of individuals with a history of IV injection of crushed tablets. We are suggesting that intravenous injection of crushed morphine tablets can cause pericardial irritation and a syndrome of acuter pericarditis. To our knowledge, there has not been a previous report of acute pericarditis secondary to intravenous injection of crushed tablets.

"Bright asteroids in the polar sky"-clinic-radio-pathological correlation in an unusual case of silicotuberculosis

We present a case of acute silicosis presenting with severe breathlessness and respiratory failure. An unusual aspect in our case was the presence of acute silicosis with respiratory failure in backdrop of long-term silica exposure. The other striking aspect in this case was the demonstration of crystalline silica particles under polarizing light in bronchial lavage fluid sample and coexistence of tuberculosis with acute silicosis.

Pulmonary Talcosis in an Immunocompromised Patient

The first case of pulmonary talcosis or talc pneumoconiosis related to inhalation of talc during its extraction and processing in mines was described by Thorel in 1896. Pulmonary talcosis is most commonly seen secondary to occupational exposure or intravenous (IV) drug abuse and, occasionally, in excessive use of cosmetic talc. Based on literature review, there has been an increase in reported incidents of pulmonary talcosis due to various forms of exposure to the mineral. We report an 82-year-old man who is diagnosed with Philadelphia chromosome positive pre-B cell acute lymphoblastic leukemia (ALL) treated with palliative imatinib who presented with chronic hemoptysis and dyspnea shortly after his diagnosis. His symptoms were initially thought to be due to an infectious etiology due to his malignancy, immunocompromised state, and radiographic findings until high-resolution computerized tomographic (HRCT) findings showed a diffuse pulmonary fibrosis picture that prompted further questioning and a more thorough history inquiry on his exposure to causative agents of interstitial lung disease. Very often, patients do not recognize their exposure, especially in those whose exposure is unrelated to their occupation. Our case emphasizes the need for thorough and careful history taking of occupational and nonoccupational exposure to known causative agents of interstitial lung disease.

Cocaine-induced pulmonary changes: HRCT findings

Objective:

To evaluate HRCT scans of the chest in 22 patients with cocaine-induced pulmonary disease.

Methods:

We included patients between 19 and 52 years of age. The HRCT scans were evaluated by two radiologists independently, discordant results being resolved by consensus. The inclusion criterion was an HRCT scan showing abnormalities that were temporally related to cocaine use, with no other apparent causal factors.

Results:

In 8 patients (36.4%), the clinical and tomographic findings were consistent with "crack lung", those cases being studied separately. The major HRCT findings in that subgroup of patients included ground-glass opacities, in 100% of the cases; consolidations, in 50%; and the halo sign, in 25%. In 12.5% of the cases, smooth septal thickening, paraseptal emphysema, centrilobular nodules, and the tree-in-bud pattern were identified. Among the remaining 14 patients (63.6%), barotrauma was identified in 3 cases, presenting as pneumomediastinum, pneumothorax, and hemopneumothorax, respectively. Talcosis, characterized as perihilar conglomerate masses, architectural distortion, and emphysema, was diagnosed in 3 patients. Other patterns were found less frequently: organizing pneumonia and bullous emphysema, in 2 patients each; and pulmonary infarction, septic embolism, eosinophilic pneumonia, and cardiogenic pulmonary edema, in 1 patient each.

Conclusions:

Pulmonary changes induced by cocaine use are varied and nonspecific. The diagnostic suspicion of cocaine-induced pulmonary disease depends, in most of the cases, on a careful drawing of correlations between clinical and radiological findings.

Inhalation of Talc Induces Infiltration of Macrophages and Upregulation of Manganese Superoxide Dismutase in Rats

Talc is a mineral that is widely used in cosmetic products, antiseptics, paints, and rubber manufacturing. Although the toxicological effects of talc have been studied extensively, until now no detailed inhalation study of talc focusing on oxidative stress has been done. This repeated 4 weeks whole-body inhalation toxicity study of talc involved Sprague-Dawley rats. Male and female groups of rats were exposed to inhaled talc at 0, 5, 50, and 100 mg/m(3) for 6 hours daily, 5 days/week for 4 weeks. The objective was to identify the 4-week inhalation toxicity of talc and investigate antioxidant activity after exposure to talc. There were no treatment-related symptoms or mortality in rats treated with talc. Glucose (GLU) was decreased significantly in male rats exposed to 50 and 100 mg/m(3) of talc. Histopathological examination revealed infiltration of macrophages on the alveolar walls and spaces near the terminal and respiratory bronchioles. In male and female rats exposed to 100 mg/m(3) talc, expression of superoxide dismutase 2, a typical biological indicator of oxidative damage, was significantly increased. Thus, inhalation of talc induces macrophage aggregations and oxidative damage in the lung.

AS, Zanetti G, Marchiori E. Can chest high-resolution computed tomography findings diagnose pulmonary alveolar microlithiasis?

OBJECTIVE

The present study was aimed at retrospectively reviewing high-resolution computed tomography (HRCT) findings in patients with pulmonary alveolar microlithiasis in order to evaluate the frequency of tomographic findings and their distribution in the lung parenchyma.

MATERIALS AND METHODS

Thirteen patients (9 females and 4 males; age, 9 to 59 years; mean age, 34.5 years) were included in the present study. The HRCT images were independently evaluated by two observers whose decisions were made by consensus. The inclusion criterion was the presence of abnormalities typical of pulmonary alveolar microlithiasis at HRCT, which precludes lung biopsy. However, in 6 cases lung biopsy was performed.

RESULTS

Ground-glass opacities and small parenchymal nodules were the predominant tomographic findings, present in 100% of cases, followed by small subpleural nodules (92.3%), subpleural cysts (84.6%), subpleural linear calcifications (69.2%), crazy-paving pattern (69.2%), fissure nodularity (53.8%), calcification along interlobular septa (46.2%) and dense consolidation (46.2%).

CONCLUSION

As regards distribution of the lesions, there was preferential involvement of the lower third of the lungs. No predominance of distribution in axial and anteroposterior directions was observed.

Role of chest computed tomography in prevention of occupational respiratory disease: review of recent literature

This review provides an update on literature published over the past 5 years that is relevant to using chest computed tomography (CT) as a tool for preventing occupational respiratory disease. An important area of investigation has been in the use of low-dose CT (LDCT) to screen asbestos-exposed populations for lung cancer. Two recent systematic reviews have reached conclusions in support of screening. Based on the limited evidence that is currently available, the Finnish Institute of Occupational Health has recommended LDCT screening in asbestos-exposed individuals if their personal combination of risk factors yields a risk for lung cancer equal to that needed for entry into the National Lung Screening Trial. It has also recommended further research, such as to document the optimal frequency of screening and the effectiveness of screening. Recent literature continues to support high-resolution CT (HRCT) as being more sensitive than chest radiography in detecting pneumoconiosis. However, there are insufficient data to determine the effectiveness of HRCT screening in improving individual outcomes if used in screening for pneumoconiosis and its routine use for this purpose cannot be recommended. However, if HRCT is used to evaluate populations, recent literature shows that the International Classification of HRCT for Occupational and Environmental Respiratory Diseases provides an important tool for reproducible evaluation and recording of findings. HRCT is an important tool for individual patient management and recent literature has documented that chest HRCT findings are significantly associated with outcomes such as pulmonary function and mortality.

Pulmonary effects of i.v. injection of crushed oral tablets: "excipient lung disease"

OBJECTIVE

When crushed oral tablets are injected i.v., their filler material (excipient) can induce a potentially fatal foreign-body reaction in pulmonary arterioles, presenting as dyspnea and pulmonary hypertension with centrilobular nodules on CT. We will describe the imaging and pathologic features of "excipient lung disease."

CONCLUSION

The radiologist has a critical role in recognizing and reporting excipient lung disease because the referring clinician may be unaware of the patient's i.v. drug abuse.

Pulmonary intravascular talcosis mimicking miliary tuberculosis in an intravenous drug addict

Pulmonary foreign body granulomatosis following intravenous administration of medications meant for oral use among drug addicts has been occasionally reported. This condition is often misdiagnosed because of its rarity, but rather due to its similarity to other pulmonary diseases that are more common. Here we report a case of pulmonary intravascular talcosis mimicking miliary tuberculosis in a young male intravenous drug addict from North-Eastern Estonia, known as a hotspot for tuberculosis and drug misuse. The condition was caused by intravenous administration of crushed tablets of diphenhydramine, but miliary tuberculosis was misdiagnosed on patient's demographical, clinical and radiological grounds and a decision to start treatment with four first-line antituberculosis drugs followed. The current report refers to the importance of considering rare causes of pulmonary disseminations with attempts to identify the causative agent and warns against the use of antituberculosis treatment without confirmation of microbiological diagnosis of tuberculosis.

Pulmonary Foreign Body Embolism and Granulomatosis in Intravenous Substance Abuse

Prescription drug abuse has increased in the United States in part because of the relative ease of acquisition. Some drug abusers resort to the injection of crushed tablets for rapid onset and increased euphoria. Adolescents and young adults with chronic pain disorders and intravenous access ports are particularly susceptible to this practice. Clinically, those who inject tablets may develop dyspnea, hypoxemia, pulmonary hypertension, and are at an increased risk of sudden death. In addition to the active ingredient(s), pharmaceutical tablets contain inert excipients such as talc, starch, microcrystalline cellulose and crospovidone. Angiothrombosis and foreign body granulomatosis induced by particulate emboli are the major pathological findings identified. Tablet excipients can be discerned by their morphological and histochemical attributes. Microanalytic techniques may be required for definitive identification. Inhalational exposures, aspiration, endogenously formed crystals, and hyperalimentation are potential mimickers of tablet-induced foreign body emboli and granulomatosis.

Rare causes of pulmonary hypertension: spectrum of radiological findings and review of the literature

Following a brief introduction covering the clinical signs and symptoms of pulmonary hypertension (PH), its most recent classification into six groups, and the computed tomography (CT) features common to all forms of PH, this paper illustrates the typical patterns that can be found on chest radiography and CT in rare causes of PH. We present and compare with the existing literature our personal series of cases of rare forms of PH, found in the following diseases: veno-occlusive disease, pulmonary capillary haemangiomatosis, non-thrombotic pulmonary embolism (tumour embolism and carcinomatous lymphangitis, talcosis, hydatid disease), pulmonary artery sarcoma, neurofibromatosis, sarcoidosis, and Langerhans cell histiocytosis. Rare forms of PH show low incidence and prevalence, and are, therefore, poorly recognised. Their diagnosis is a challenge for clinicians, pathologists, and radiologists, and any additional knowledge about the CT findings may help the diagnosis in the case of patients affected by PH of unknown origin.