Drug-induced pneumonitis: thin-section CT findings in 60 patients

Case 327: Exogenous Lipoid Pneumonia

HISTORY

A 58-year-old male patient with an active smoking status was admitted twice to the intensive care unit (ICU) of a tertiary referral thoracic center for severe hypercapnic acute respiratory failure and persistent bilateral chest radiograph opacities that were unchanged over the course of the two ICU admissions within a 3-month period. The patient had obesity (body mass index, 36), stage 3 vascular chronic renal insufficiency, and hebephrenic schizophrenia treated with haloperidol, carbamazepine, and cyamemazine. He reported chronic dyspnea on exertion, which worsened for 6 months. At the second ICU admission, the patient was afebrile, with a blood pressure of 160/72 mm Hg and pulse oximetry of 93% on 6 L/min oxygen therapy through a nonrebreathing mask. Physical examination showed signs of respiratory failure with wheezing and active abdominal expiration, and bilateral pulmonary crackles without chest pain, hemoptysis, clubbing, or signs of cardiac failure. The patient had no peripheral lymphadenopathy and no enlarged spleen. Blood gases (on 6 L/min oxygen) showed respiratory acidosis (pH, 7.15 [normal range, 7.38-7.42]; PaO2 level, 67 mm Hg [normal range, 80-100 mm Hg]; PaCO2 level, 102 mm Hg [normal range, 38-42 mm Hg]; bicarbonate [HCO3-], 29 mmol/L [normal range, 22-27 mmol/L]). Noninvasive ventilation was initiated. Imaging performed during the second ICU hospitalization included CT and MRI of the chest without contrast enhancement, and fluorine 18 (18F) fluorodeoxyglucose (FDG) PET/CT.

Uncommon Causes of Interlobular Septal Thickening on CT Images and Their Distinguishing Features

Interlobular septa thickening (ILST) is a common and easily recognized feature on computed tomography (CT) images in many lung disorders. ILST thickening can be smooth (most common), nodular, or irregular. Smooth ILST can be seen in pulmonary edema, pulmonary alveolar proteinosis, and lymphangitic spread of tumors. Nodular ILST can be seen in the lymphangitic spread of tumors, sarcoidosis, and silicosis. Irregular ILST is a finding suggestive of interstitial fibrosis, which is a common finding in fibrotic lung diseases, including sarcoidosis and usual interstitial pneumonia. Pulmonary edema and lymphangitic spread of tumors are the commonly encountered causes of ILST. It is important to narrow down the differential diagnosis as much as possible by assessing the appearance and distribution of ILST, as well as other pulmonary and extrapulmonary findings. This review will focus on the CT characterization of the secondary pulmonary lobule and ILST. Various uncommon causes of ILST will be discussed, including infections, interstitial pneumonia, depositional/infiltrative conditions, inhalational disorders, malignancies, congenital/inherited conditions, and iatrogenic causes. Awareness of the imaging appearance and various causes of ILST allows for a systematic approach, which is important for a timely diagnosis. This study highlights the importance of a structured approach to CT scan analysis that considers ILST characteristics, associated findings, and differential diagnostic considerations to facilitate accurate diagnoses.

Tips and Tricks in Thoracic Radiology for Beginners: A Findings-Based Approach

This review has the purpose of illustrating schematically and comprehensively the key concepts for the beginner who approaches chest radiology for the first time. The approach to thoracic imaging may be challenging for the beginner due to the wide spectrum of diseases, their overlap, and the complexity of radiological findings. The first step consists of the proper assessment of the basic imaging findings. This review is divided into three main districts (mediastinum, pleura, focal and diffuse diseases of the lung parenchyma): the main findings will be discussed in a clinical scenario. Radiological tips and tricks, and relative clinical background, will be provided to orient the beginner toward the differential diagnoses of the main thoracic diseases.

Marijuana-Induced Lung Injury: A Case Report and a Review of the Literature

Marijuana is a commonly abused illicit substance around the world, and lung injury related to its use has seldom been cited in the literature. Most cases describe marijuana-induced lung injury via vaping and the use of butane hash oil; however, no cases, to our knowledge, have associated lung injury related to marijuana smoke in the form of rolled "blunts" or cigarettes. We describe the case of a patient who presented to the hospital due to chest computed tomography findings demonstrating diffuse bilateral opacifications without signs of systemic inflammatory response syndrome. Bronchoscopy with bronchoalveolar lavage and sputum cultures failed to identify an infectious etiology, and serologies were negative for autoimmune etiologies. We aim to contribute to the limited body of literature describing marijuana-induced lung injury.

Differential diagnosis of infectious diseases, drug-induced lung injury, and pulmonary infiltration due to underlying malignancy in patients with hematological malignancy using HRCT

PURPOSE

To differentiate among infectious diseases, drug-induced lung injury (DILI) and pulmonary infiltration due to underlying malignancy (PIUM) based on high-resolution computed tomographic (HRCT) findings from patients with hematological malignancies who underwent chemotherapy or hematopoietic stem cell transplantation.

MATERIALS AND METHODS

A total of 221 immunocompromised patients with hematological malignancies who had proven chest complications (141 patients with infectious diseases, 24 with DILI and 56 with PIUM) were included. Two chest radiologists evaluated the HRCT findings, including ground-glass opacity, consolidation, nodules, and thickening of bronchovascular bundles (BVBs) and interlobular septa (ILS). After comparing these CT findings among the three groups using the χ2test, multiple logistic regression analyses (infectious vs noninfectious diseases, DILI vs non-DILI, and PIUM vs non-PIUM) were performed to detect useful indicators for differentiation.

RESULTS

Significant differences were detected in many HRCT findings by the χ2 test. The results from the multiple logistic regression analyses identified several indicators: nodules without a perilymphatic distribution [p = 0.012, odds ratio (95% confidence interval): 4.464 (1.355-11.904)], nodules with a tree-in-bud pattern [p = 0.011, 8.364 (1.637-42.741)], and the absence of ILS thickening[p = 0.003, 3.621 (1.565-8.381)] for infectious diseases, the presence of ILS thickening [p = 0.001, 7.166 (2.343-21.915)] for DILI, and nodules with a perilymphatic distribution [p = 0.011, 4.256 (1.397-12.961)] and lymph node enlargement (p = 0.008, 3.420 (1.385-8.441)] for PIUM.

CONCLUSION

ILS thickening, nodules with a perilymphatic distribution, tree-in-bud pattern, and lymph node enlargement could be useful indicators for differentiating among infectious diseases, DILI, and PIUM in patients with hematological malignancies.

Imaging of Drug-Related Pneumonitis in Oncology

Clinical applications of novel anticancer agents in the past few decades brought marked advances in cancer treatment, enabling remarkable efficacy and effectiveness; however, these novel agents are also associated with toxicities. Among various toxicities, drug-related pneumonitis is one of the major clinical challenges in the management of cancer patients. Imaging plays a key role in detection, diagnosis, and monitoring of drug-related pneumonitis during cancer treatment. In the current era of precision oncology, pneumonitis from molecular targeted therapy and immune-checkpoint inhibitors (ICI) has been recognized as an event of clinical significance. Additionally, further advances of therapeutic approaches in cancer have brought several emerging issues in diagnosis and monitoring of pneumonitis. This article will describe the computed tomography (CT) pattern-based approach for drug-related pneumonitis that has been utilized to describe the imaging manifestations of pneumonitis from novel cancer therapies. Then, we will discuss pneumonitis from representative agents of precision cancer therapy, including mammalian target of rapamycin inhibitors, epidermal growth factor receptor inhibitors, and ICI, focusing on the incidence, risk factors, and the spectrum of CT patterns. Finally, the article will address emerging challenges in the diagnosis and monitoring of pneumonitis, including pneumonitis from combination ICI and radiation therapy and from antibody conjugate therapy, as well as the overlapping imaging features of drug-related pneumonitis and coronavirus disease 2019 pneumonia. The review is designed to provide a practical overview of drug-related pneumonitis from cutting-edge cancer therapy with emphasis on the role of imaging.

Serum Biomarkers in a Radiological Pattern of Non-Fibrotic Hypersensitivity Pneumonitis: Implications for Mechanistic Difference and Differential Diagnosis

Hypersensitivity pneumonitis (HP) is a consequence of immune-mediated reactions caused by recurrent exposure to environmental agents. Recently, clinical practice guidelines for the diagnosis of HP were published and increased interest in HP. On the other hand, novel therapies have recently emerged for various diseases, and the management of drug-related pneumonitis (DRP) has become increasingly important. Among DRP, the HP pattern (DRP-HP) shows small, poorly defined centrilobular nodules with or without widespread areas of ground-glass opacity or lobular areas of decreased attenuation and vascularity. A similar radiological pattern of non-fibrotic HP can be induced, irrespective of inhalation (non-fibrotic HP) or intravenous administration (DRP-HP). However, their difference has not been well described, although the distribution of lesions in the lungs was slightly different between these two conditions. In this review, we focus on serum biomarkers of lung epithelial cells in order to investigate the difference between DRP-HP and non-fibrotic HP (common-HP). Serum levels of Krebs von den Lungen 6 (KL-6) might be relatively lower (occasionally normal) in DRP-HP than in common-HP, implying a mechanistic difference. KL-6 could be useful in discriminating between DRP and non-fibrotic HP (common type).

Persistent Fever While on Broad-Spectrum Antibiotics in a Patient With Squamous Cell Carcinoma

For solid tumor patients, acute infectious process is often underestimated, especially when caused by fungal, viral, or other atypical pathogens. Providers should perform a comprehensive infectious workup to rule out uncommon pathogen-induced infection before considering tumor fever. Active infection can be life threatening given most patients with cancer are receiving chemotherapy, immunotherapy, or even cellular therapy, as is the case with the patient discussed in this article.

Interstitial Lung Disease Induced by Anti-ERBB2 Antibody-Drug Conjugates: A Review

Importance

In the past decade, ERBB2 (formerly HER2)-directed antibody-drug conjugates (ADCs) have substantially changed treatment of both advanced and early-stage ERBB2-positive breast cancer. Novel conjugates are now showing activity in trials of other ERBB2-associated tumors, leading to the recent US Food and Drug Administration approval of trastuzumab deruxtecan for ERBB2-positive gastric cancer, as well as beneficial results in colorectal, lung, and bladder cancer. It is thus possible that anti-ERBB2 ADCs may become a treatment option for multiple types of tumors because many have at least some expression of ERBB2. Despite an improved overall therapeutic index, clinical observations have recently raised a concern regarding potential lung toxicity of anti-ERBB2 ADCs. Deaths related to interstitial lung disease (ILD) have been reported with variable incidence in trials testing anti-ERBB2 conjugates, warranting appropriate training of clinicians for the identification and management of this toxic effect.

Observations

Although no specific guidelines are available for the diagnosis and management of ADC-related ILD, some recommendations can be derived based on general principles adopted for drug-induced and immunotherapy-related ILD. Overall, in symptomatic ILD, the ADC should be discontinued. Reintroduction of the conjugate can be considered only in asymptomatic cases after complete resolution. Corticosteroids represent the cornerstone of ILD treatment, and dosing should be adapted according to the severity of the event. Additional treatments can be considered based on the clinical scenario.

Conclusions and Relevance

This review summarizes the current knowledge on the pathogenesis and epidemiologic characteristics of anti-ERBB2 ADC-related lung toxicity, proposing strategies for its diagnosis and treatment. Earlier diagnosis and more adequate treatment of ADC-induced ILD may improve the therapeutic index of this important class of anticancer agents, allowing for a safe expansion of anti-ERBB2 ADCs across tumor types.

Drug-related pneumonitis with radiographic hypersensitivity pneumonitis pattern: Three case series

Novel therapies have recently emerged for various diseases, and the management of drug-related pneumonitis (DRP) has become increasingly important. In particular, the hypersensitivity pneumonitis (HP) pattern of DRP has been increasingly recognized due to development of new therapeutic strategies, such as immunotherapy. However, literature describing detailed clinical cases is still lacking.

Herein, we report three cases of DRP with typical HP radiographic pattern. These patients were treated with different drugs, namely nano albumin-bound (nab)-paclitaxel, everolimus, or nivolumab, but had common clinical features, including a good prognosis.

Interstitial lung disease induced by the roots of Achyranthes japonica Nakai: Three case reports

BACKGROUND

The roots of Achyranthes japonica Nakai (AJN), called “Useul-puli,” has been traditionally used to control pain and improve dysfunction in osteoarthritis patients in South Korea.

CASE SUMMARY

We described 3 patients diagnosed with herbal medicine induced interstitial lung disease after consuming boiled the roots of AJN. They were referred to our hospital because of the modified Medical Research Council grade 4 dyspnea. Chest computed tomography showed bilateral ground-glass opacities with patchy consolidation. After treatment with systemic glucocorticoid therapy and discontinuation of the roots of AJN, their symptoms improved, and almost all ground-glass opacities and patchy consolidations on chest radiography and chest computed tomography resolved.

CONCLUSION

We present three cases of interstitial lung disease induced by the roots of AJN.

Steroid-refractory PD-(L)1 pneumonitis: incidence, clinical features, treatment, and outcomes

BACKGROUND

Immune-checkpoint inhibitor (ICI)-pneumonitis that does not improve or resolve with corticosteroids and requires additional immunosuppression is termed steroid-refractory ICI-pneumonitis. Herein, we report the clinical features, management and outcomes for patients treated with intravenous immunoglobulin (IVIG), infliximab, or the combination of IVIG and infliximab for steroid-refractory ICI-pneumonitis.

METHODS

Patients with steroid-refractory ICI-pneumonitis were identified between January 2011 and January 2020 at a tertiary academic center. ICI-pneumonitis was defined as clinical or radiographic lung inflammation without an alternative diagnosis, confirmed by a multidisciplinary team. Steroid-refractory ICI-pneumonitis was defined as lack of clinical improvement after high-dose corticosteroids for 48 hours, necessitating additional immunosuppression. Serial clinical, radiologic (CT imaging), and functional features (level-of-care, oxygen requirement) were collected preadditional and postadditional immunosuppression.

RESULTS

Of 65 patients with ICI-pneumonitis, 18.5% (12/65) had steroid-refractory ICI-pneumonitis. Mean age at diagnosis of ICI-pneumonitis was 66.8 years (range: 35-85), 50% patients were male, and the majority had lung carcinoma (75%). Steroid-refractory ICI-pneumonitis occurred after a mean of 5 ICI doses from PD-(L)1 start (range: 3-12 doses). The most common radiologic pattern was diffuse alveolar damage (DAD: 50%, 6/12). After corticosteroid failure, patients were treated with: IVIG (n=7), infliximab (n=2), or combination IVIG and infliximab (n=3); 11/12 (91.7%) required ICU-level care and 8/12 (75%) died of steroid-refractory ICI-pneumonitis or infectious complications (IVIG alone=3/7, 42.9%; infliximab alone=2/2, 100%; IVIG + infliximab=3/3, 100%). All five patients treated with infliximab (5/5; 100%) died from steroid-refractory ICI-pneumonitis or infectious complications. Mechanical ventilation was required in 53% of patients treated with infliximab alone, 80% of those treated with IVIG + infliximab, and 25.5% of those treated with IVIG alone.

CONCLUSIONS

Steroid-refractory ICI-pneumonitis constituted 18.5% of referrals for multidisciplinary irAE care. Steroid-refractory ICI-pnuemonitis occurred early in patients' treatment courses, and most commonly exhibited a DAD radiographic pattern. Patients treated with IVIG alone demonstrated an improvement in both level-of-care and oxygenation requirements and had fewer fatalities (43%) from steroid-refractory ICI-pneumonitis when compared to treatment with infliximab (100% mortality).

Rifampicin-Induced Pneumonitis Mimicking Severe COVID-19 Pneumonia Infection

Patient: Male, 43-year-old

Final Diagnosis: Rifampicin-induced pneumonitis

Symptoms: Dyspnea • fatigue • fever

Medication: —

Clinical Procedure: Bronchoalveolar lavage • bronchoscopy • CT scan • lung biopsy

Specialty: Pulmonology

Chest complications in immunocompromised patients without acquired immunodeficiency syndrome (AIDS): differentiation between infectious and non-infectious diseases using high-resolution CT findings

AIM

To differentiate between infectious and non-infectious diseases occurring in immunocompromised patients without acquired immunodeficiency syndrome (AIDS) using high-resolution computed tomography (HRCT).

MATERIALS AND METHODS

HRCT images of 555 patients with chest complications were reviewed retrospectively. Infectious diseases (n=341) included bacterial pneumonia (n=123), fungal infection (n=80), septic emboli (n=11), tuberculosis (n=15), pneumocystis pneumonia (n=101), and cytomegalovirus pneumonia (n=11), while non-infectious diseases (n=214) included drug toxicity (n=84), infiltration of underlying diseases (n=83), idiopathic pneumonia syndrome (n=34), diffuse alveolar haemorrhage (n=8), and pulmonary oedema (n=5). Lung parenchymal abnormalities were compared between the two groups using the χ² test and multiple logistic regression analysis.

RESULTS

The χ2 test results showed significant differences in many HRCT findings between the two groups. Multiple logistic regression analysis results indicated the presence of nodules with a halo and the absence of interlobular septal (ILS) thickening were the significant indicators that could differentiate infectious from non-infectious diseases. ILS thickening was generally less frequent among most infectious diseases and more frequent among most non-infectious diseases, with a good odds ratio (7.887, p<0.001). The sensitivity and accuracy for infectious diseases in the absence of ILS thickening were better (70% and 73%, respectively) than those of nodules with a halo (19% and 48%, respectively), while the specificity in the nodules with a halo was better (93%) than that of ILS thickening (78%).

CONCLUSIONS

The presence of nodules with a halo or the absence of ILS thickening tends to suggest infectious disease. Specifically, ILS thickening seems to be a more reliable indicator.

Epidemiology and Risk Factors for Severe Delayed Drug Hypersensitivity Reactions

Severe delayed drug hypersensitivity reactions comprise different clinical entities and can involve different immune-mediated mechanisms. Common examples are severe cutaneous adverse reactions and druginduced internal organ injuries. The incidence of such reactions is overall low but seems to be on the rise reaching numbers as high as 9 per million individuals-years in the case of SJS/TEN and DRESS. Such conditions carry an important associated morbidity, and mortality can attain 40% in SJS/TEN patients, making these hypersensitivity reactions important targets when implementing preventive measures. Several risk factors have been identified for reaction severity; some are transverse, such as older age and underlying chronic diseases. The recent advances in pharmacogenetics allowed the identification of specific populations with higher risk and permitted strategic avoidance of certain drugs being HLA-B*57:01 screening in patients initiating abacavir the best successful example. In this work, we reviewed the epidemiology of SCARs and liver/kidney/lung drug-induced immune-mediated reactions. We focus on particular aspects such as prevalence and incidence, drugs involved, mortality and risk factors.

Osimertinib in Pulmonary Manifestations: Two Case Reports and Review of the Literature

Osimertinib is an oral, irreversible epidermal growth factor receptor inhibitor that is associated with various pulmonary manifestations including transient asymptomatic pulmonary opacities (TAPOs) and pneumonitis. We present a case of a 61-year-old female with Stage IV lung adenocarcinoma, who developed bilateral ground glass opacities on her chest-computed tomography (CT) three months after initiating osimertinib. Her imaging findings were thought to represent lymphangitic carcinomatosis responding to chemotherapy rather than drug induced toxicity, and she was continued on osimertinib. Conversely, we present a second case of a 57-year-old female with Stage IV lung adenocarcinoma who developed osimertinib-induced pneumonitis and was successfully rechallenged with osimertinib and glucocorticoids. These cases, described herein, illustrate examples of the range of pulmonary manifestations of osimertinib, as well as the safety of rechallenging patients with osimertinib and glucocorticoids following the development of pneumonitis.

Modified-BEP Chemotherapy in Patients With Germ-Cell Tumors Treated at a Comprehensive Cancer Center

OBJECTIVES

Bleomycin, etoposide, and cisplatin (BEP) is the most common and successful chemotherapy regimen for germ-cell tumor (GCT) patients, accompanied by a bleomycin-induced dose-dependent lung toxicity in certain patients. In an attempt to reduce bleomycin-toxicity, we developed a modified-BEP (mBEP) regimen.

MATERIALS AND METHODS

Between August 2008 and February 2018, 182 unselected mainly testicular GCT patients (39 with adjuvant purpose and 143 with curative purpose) received a tri-weekly 5-day hospitalization schedule with bleomycin 15 U intravenous (IV) push on day 1 and 10 U IV continuous infusion over 12 hours on days 1 to 3, cisplatin 20 mg/m IV, and etoposide 100 mg/m IV on days 1 to 5. Pulmonary toxicity was assessed through chest computed tomography scan and clinical monitoring.

RESULTS

Median number of mBEP cycles was 3 (range: 1 to 4). In the curative setting, according to the International Germ Cell Cancer Collaborative Group (IGCCCG) prognostic system, 112, 21, and 9 patients had good-risk, intermediate-risk, and poor-risk class, respectively; 66 (46%) patients had complete response (CR), 67 (47%) had partial response (52 of whom became CR afterwards), 6 (4%) had stable disease (that in 3 became CR afterwards), 3 (2%) progressed, and 1 (1%) died of brain stroke. At a median follow-up of 2.67 years (interquartile range: 1.23-5.00 y), 1 and 5-year overall survival and progression-free survival were 99% and 95%, and 90% and 88%, respectively. In the entire patient population, there was grade 3/4 neutropenia in 92 patients (51%), febrile neutropenia in 11 patients (6%), grade 1/2 nausea in 74 patients (41%), and no death due to pulmonary toxicity.

CONCLUSION

In GCT patients, our mBEP-schedule would suggest an effective treatment modality without suffering meaningful pulmonary toxicity.

Anaplastic lymphoma kinase inhibitor related pneumonitis in patients with non-small cell lung cancer: Clinical and radiologic characteristics and risk factors

Anaplastic lymphoma kinase (ALK) inhibitor-related pneumonitis (ALK-IIP) is relatively rare but sometimes fatal, so the timely diagnosis of ALK-IIP is important for enabling prompt management. However, the detailed radiologic characteristics and clinical course of ALK-IIP are still unclear. This study was performed to investigate the clinical and radiologic characteristics and risk factors of ALK-IIP in patients with non-small cell lung cancer (NSCLC).A total of 250 NSCLC patients who had been treated with ALK inhibitors were retrospectively enrolled. Chest computed tomography (CT) was classified into 4 CT patterns using the 2013 guideline for idiopathic interstitial pneumonia: cryptogenic organizing pneumonia (COP), hypersensitivity pneumonitis (HP), acute interstitial pneumonia (AIP), and nonspecific interstitial pneumonia. Clinical characteristics including toxicity grading and treatment course were analyzed in regarding to CT patterns. Clinical characteristics were compared between patients with ALK-IIP and without ALK-IIP.ALK-IIP was identified in 11 patients (4.4%). The most common CT pattern was the COP pattern (n = 7, 63.6%) and followed by HP and AIP patterns (both, n = 2, 18.2%). ALK-IIP showed pneumonitis toxicity grade ranged from 1 to 4, and AIP pattern had the highest toxicity grade, followed by HP and COP patterns (median grade: 3.5, 2.5, 1). All of the patients with the COP pattern were successfully treated, while half of patients with the AIP pattern died during treatment. The smoking history and extrathoracic metastasis were more frequent in patients with ALK-IIP (P < .005). The smoking history was associated with a higher incidence of ALK-IIP (odds ratio: 3.586, 95% confidence interval: 1.058-13.432, P = .049).ALK-IIP showed a spectrum of chest CT patterns, which reflected the toxicity grades. The COP pattern was the most common CT pattern of ALK-IIP, and patients with ALK-IIP of the COP pattern were successfully treated. ALK inhibitors should be used with caution in NSCLC patients with smoking history.

Significance of baseline computed tomography assessment for predicting the pulmonary fibrosis during the course of chemotherapy-induced pneumonitis

BACKGROUND

The purpose of our study is to evaluate risk factors for the development of pulmonary fibrosis in the baseline computed tomography (CT) during the course of chemotherapy-induced pneumonitis (CIP).

METHODS

We retrospectively identified 80 cases of CIP by clinical, radiological, and pathological findings. When fibrosis developed during the follow-up, the extent of pulmonary fibrosis was evaluated at final follow-up CT in terms of a 5% volumetric score for six zones. Univariate and multivariate analyses were performed to identify the clinical and radiological risk factors for the development of fibrosis and severe fibrosis over 11% in extent.

RESULTS

Fibrosis occurred in 26 of the 80 total patients (32.5%) during a mean 5.6 months of follow up. Risk factors for developing fibrosis were revealed as preexisting interstitial lung disease (ILD) and moderate to severe emphysema in multivariate analysis (OR = 10.12, 95% CI = 2.35-43.66, and OR = 12.85, 95% CI = 2.81-58.82, respectively). Risk factors for developing severe fibrosis over 11% in extent were revealed as a moderate to severe emphysema (OR = 5.78, 95% CI = 1.07-31.26) in multivariate analysis.

CONCLUSIONS

Moderate to severe emphysema as well as preexisting ILD visible on baseline CT are risk factors for developing pulmonary fibrosis in the course of CIP. Thin-section CT may be helpful to predict the risk of pulmonary fibrosis before administering chemotherapy.

Radiologic evaluation of pulmonary injury following carmustine- and cyclophosphamide-based preparative regimen for autologous peripheral blood stem cell transplantation in children

BACKGROUND

Toxicity of carmustine and cyclophosphamide can cause pulmonary injury after hematopoietic stem cell transplantation.

OBJECTIVE

To evaluate the radiologic findings of pulmonary injuries following carmustine- and cyclophosphamide-based preparative regimens in children.

MATERIALS AND METHODS

From 2010 to 2014, 35 children received carmustine- and cyclophosphamide-based preparative regimens. Fourteen of 35 children presented with symptoms and radiologic abnormalities. Eight of 14 children had no evidence of infection, cardiogenic edema, or other explainable causes. We retrospectively analyzed their chest radiographs and CT scans for ground-glass opacity, consolidation, septal thickening and pleural effusion.

RESULTS

Major chest radiographic findings were bilateral diffuse ground-glass opacity (n=8) and septal thickening (n=7). CT findings were multifocal patchy (n=4) or inhomogeneously diffuse (n=4) ground-glass opacity, multifocal consolidations (n=7) and septal thickening (n=7). All of these lesions at CT were bilateral, but showed lower lobe predominance in 88, 100, and 63%, respectively. There was no central/peripheral or anterior/posterior predilection. Six children had small pleural effusions, which were bilateral in five children.

CONCLUSION

Bilateral ground-glass opacity with or without consolidation, septal thickening and pleural effusion were common radiologic findings in pulmonary injury following carmustine- and cyclophosphamide-based preparative regimens.

Drug-Induced Interstitial Lung Disease: A Systematic Review

Background: Drug-induced interstitial lung disease (DIILD) occurs as a result of numerous agents, but the risk often only becomes apparent after the marketing authorisation of such agents. Methods: In this PRISMA-compliant systematic review, we aimed to evaluate and synthesise the current literature on DIILD. Results: Following a quality assessment, 156 full-text papers describing more than 6000 DIILD cases were included in the review. However, the majority of the papers were of low or very low quality in relation to the review question (78%). Thus, it was not possible to perform a meta-analysis, and descriptive review was undertaken instead. DIILD incidence rates varied between 4.1 and 12.4 cases/million/year. DIILD accounted for 3–5% of prevalent ILD cases. Cancer drugs, followed by rheumatology drugs, amiodarone and antibiotics, were the most common causes of DIILD. The radiopathological phenotype of DIILD varied between and within agents, and no typical radiological pattern specific to DIILD was identified. Mortality rates of over 50% were reported in some studies. Severity at presentation was the most reliable predictor of mortality. Glucocorticoids (GCs) were commonly used to treat DIILD, but no prospective studies examined their effect on outcome. Conclusions: Overall high-quality evidence in DIILD is lacking, and the current review will inform larger prospective studies to investigate the diagnosis and management of DIILD.

Immune Checkpoint Immunotherapy for Non-Small Cell Lung Cancer: Benefits and Pulmonary Toxicities

Immune checkpoint inhibitors (ICIs) are newer, immunotherapy-based drugs that have been shown to improve survival in advanced non-small cell lung cancer (NSCLC). Unlike traditional chemotherapeutic agents, ICIs work by boosting the body's natural tumor killing response. However, this unique mechanism of action has also led to the recognition of class-specific side effects. Labeled immune-related adverse events, these toxicities can affect multiple organ systems including the lungs. Immune-mediated lung injury because of ICI use, termed checkpoint inhibitor pneumonitis (CIP), occurs in about 3% to 5% of patients receiving ICIs; however, the real-world incidence of this entity may be higher, especially now that ICIs are being used in nonclinical trial settings. In this review, we briefly introduce the biology of ICIs and the indications for ICI use in NSCLC and then discuss the epidemiology and clinical and radiologic manifestations of CIP. Next, we discuss management strategies for CIP, including the current consensus on management of steroid-refractory CIP. Given the nascent nature of this field, we highlight areas of uncertainty and emerging research questions in the burgeoning field of checkpoint inhibitor pulmonary toxicity.

Interstitial Lung Disease After Kidney Transplantation and the Role of Everolimus

BACKGROUND

Kidney transplant recipients are at higher risk of developing pulmonary complications related to immunosuppression, and inhibitor of the mammalian target of rapamycin (mTORi) has been reported as a potential cause.

METHODS

Five hundred kidney-transplanted patients were retrospectively analyzed for pulmonary complications on the basis of clinical and instrumental data (chest radiography, high-resolution computed tomography, broncho-alveolar lavage, oximetry).

RESULTS

We found 26 interstitial lung diseases (ILD) (16%): 12 cases (46.2%) were from infections (42.8% by Pneumocystis jirovecii) and 14 cases of ILD (53.8%) resulted as drug-induced ILD (DI-ILD). According to anti-rejection protocols, DI-ILD occurred in 8 patients (57%) while on triple regimen including steroids, everolimus (EVL), and cyclosporine (CyA) and in 6 patients on double regimen with steroids and mTORi: EVL or sirolimus (43%). In ILD+ patients, everolimus trough-concentration (EVL(TLC)) and cyclosporine (2nd-hour concentration: CyA(C2)) levels were higher than in patients in the same regimen but with ILD- (EVL(TLC) [ng/mL] 9.84 versus 6.85; CyA(C2) [ng/mL] 303.97 versus 298.56). The formula that used the combined blood levels of both drugs (EVL(TLC) + CyA(C2)/100) resulted in a significant difference between groups of patients (12.88 ± 1.61 versus 9.83 ± 1.91). Applying receiver operator characteristic curve (ROC) analysis to detect risk of developing ILD when on combined protocol with EVL and CyA, we obtained an area under the curve of 0.8622 (P = .0081) and 0.9082 (P = .0028), respectively, when using EVL(TLC) or the combination formula with both drugs.

CONCLUSIONS

In renal transplant patients, we obtained a relationship of ILD to specific drug concentration. On the basis of ROC analysis, patients on EVL and CyA combined protocol are at risk of ILD when EVL(TLC) is >9.03 ng/mL or >11.41 when a formula with summation of EVL(TLC) and CyA(C2) is used.

Successful desensitization therapy for a patient with isoniazid-induced hypersensitivity pneumonia

A 57-year-old male was diagnosed with mycobacterium tuberculoma and was treated with isoniazid, rifampicin, ethambutol, and pyrazinamide. Three weeks after initiation of treatment, he presented with fever and appetite loss. Chest radiograph showed diffuse micronodular shadows on both lung fields. High-resolution chest computed tomography findings were diffuse parenchymal micronodules in both lungs, which was consistent with hypersensitivity pneumonia. Because drug-induced pneumonia was suspected, the antituberculous regimen was discontinued. The symptoms and diffuse micronodular shadows improved. A drug lymphocyte stimulation test was only positive for isoniazid, so we suspected that the pneumonia was induced by isoniazid. Rifampicin and ethambutol were reintroduced without any recurrence of the abnormal shadows. Next, we tried desensitization to isoniazid over a period of two weeks, which was successful without any adverse events. Although isoniazid-induced pneumonia is extremely rare, it is important to recognize that isoniazid can cause such an adverse reaction. In addition, drug desensitization may be useful in drug-induced pneumonia.

Thin-Section CT Characteristics and Longitudinal CT Follow-up of Chemotherapy Induced Interstitial Pneumonitis: A Retrospective Cohort Study

To describe the computed tomography (CT) features of chemotherapy-induced interstitial pneumonitis (CIIP) with longitudinal follow-up.The study was approved by the local ethics committee. One hundred consecutive patients with CIIP between May 2005 and March 2015 were retrospectively enrolled. The initial CT was reviewed by 2 independent chest radiologists and categorized into 1 of 4 CT patterns in accordance with the 2013 guidelines for idiopathic interstitial pneumonia: nonspecific interstitial pneumonia (NSIP), organizing pneumonia (OP), hypersensitivity pneumonitis (HP) mimicking desquamative interstitial pneumonitis, and diffuse alveolar damage (DAD). We assessed semiquantitative analysis on a 5% scale to assess the extent of parenchymal abnormalities (emphysema, reticulation, ground-glass opacity, consolidation, honeycombing cyst) and their distribution on initial (n = 100), subsequent (n = 87), and second follow-up CT (n = 48). Interval changes in extent on follow-up CT were compared using paired t test. The clinic-radiologic factors were compared between Group 1 (NSIP and OP patterns) and Group 2 (HP and DAD patterns) using χ and independent t tests.The most common pattern of CIIP on the initial CT was HP (51%), followed by NSIP (23%), OP (20%), and DAD (6%). Diffuse ground-glass opacity was the most common pulmonary abnormality. The predominant distribution was bilateral (99%) and symmetric (82%), with no craniocaudal (60%) or axial (79%) dominance. Subsequent and second follow-up CTs showed decreased extent of total pulmonary abnormalities (P < 0.001, respectively). In comparison with Group 1 CIIP, Group 2 CIIP was more likely to be caused by molecularly targeted drugs (P = 0.030), appeared earlier (P = 0.034), and underwent more complete resolution (P < 0.001). Use of a CT pattern-recognition approach to CIIP is appropriate and practical in interpreting radiological findings.

Drug-induced interstitial lung disease in molecular targeted therapies: high-resolution CT findings

Drug-induced lung injury (DLI) comprises a wide variety of pathologies, each with a unique imaging pattern, so there are no characteristic imaging findings to establish diagnosis. When DLI is suspected, evaluation must exclude progression of underlying disease, infection, and mimicking diseases. Correct diagnosis requires integration of clinical information and radiologic, laboratory, and pathological findings when available. We describe the radiologic findings of DLI, the roles of the findings in the management of patients with DLI, and the limitations of radiologic diagnosis.

Drug induced interstitial lung disease

With an increasing number of therapeutic drugs, the list of drugs that is responsible for severe pulmonary disease also grows. Many drugs have been associated with pulmonary complications of various types, including interstitial inflammation and fibrosis, bronchospasm, pulmonary edema, and pleural effusions. Drug-induced interstitial lung disease (DILD) can be caused by chemotherapeutic agents, antibiotics, antiarrhythmic drugs, and immunosuppressive agents. There are no distinct physiologic, radiographic or pathologic patterns of DILD, and the diagnosis is usually made when a patient with interstitial lung disease (ILD) is exposed to a medication known to result in lung disease. Other causes of ILD must be excluded. Treatment is avoidance of further exposure and systemic corticosteroids in patients with progressive or disabling disease.

Drug-induced lung injury associated with sorafenib: analysis of all-patient post-marketing surveillance in Japan

BACKGROUND

Sorafenib is a multi-kinase inhibitor currently approved in Japan for unresectable and/or metastatic renal cell carcinoma and unresectable hepatocellular carcinoma. Although drug-induced lung injury has recently been the focus of interest in Japanese patients treated with molecular targeting agents, the clinical features of patients receiving sorafenib remain to be completely investigated.

METHODS

All-patient post-marketing surveillance data was obtained within the frame of Special Drug Use Investigation; between April 2008 and March 2011, we summarized the clinical information of 62 cases with drug-induced lung injury among approximately 13,600 sorafenib-treated patients in Japan. In addition, we summarized the results of evaluation by a safety board of Japanese experts in 34 patients in whom pulmonary images were available. For the calculation of reporting frequency, interim results of Special Drug Use Investigation were used.

RESULTS

In the sets of completed reports (2,407 in renal cell carcinoma and 647 in hepatocellular carcinoma), the reporting frequency was 0.33 % (8 patients; fatal, 4/8) and 0.62 % (4 patients; fatal, 2/4), respectively. Major clinical symptoms included dyspnea, cough, and fever. Evaluation of the images showed that 18 cases out of 34 patients had a pattern of diffuse alveolar damage. The patients with hepatocellular carcinoma showed a greater incidence and earlier onset of lung injury than those with renal cell carcinoma.

CONCLUSION

Although the overall reporting frequency of sorafenib-induced lung injury is not considered high, the radiological diffuse alveolar damage pattern led to a fatal outcome. Therefore, early recognition of sorafenib-induced lung injury is crucial for physicians and patients.

Drug-induced interstitial lung disease: mechanisms and best diagnostic approaches

Drug-induced interstitial lung disease (DILD) is not uncommon and has many clinical patterns, ranging from benign infiltrates to life-threatening acute respiratory distress syndrome. There are two mechanisms involved in DILD, which are probably interdependent: one is direct, dose-dependent toxicity and the other is immune-mediated. Cytotoxic lung injury may result from direct injury to pneumocytes or the alveolar capillary endothelium. Drugs can induce all types of immunological reactions described by Gell and Coombs; however, most reactions in immune-mediated DILD may be T cell-mediated.

DILD can be difficult to diagnose; diagnosis is often possible by exclusion alone. Identifying the causative drug that induces an allergy or cytotoxicity is essential for preventing secondary reactions.

One method to confirm the diagnosis of a drug-induced disease is re-exposure or re-test of the drug. However, clinicians are reluctant to place patients at further risk of illness, particularly in cases with severe drug-induced diseases. Assessment of cell-mediated immunity has recently increased, because verifying the presence or absence of drug-sensitized lymphocytes can aid in confirmation of drug-induced disease. Using peripheral blood samples from drug-allergic patients, the drug-induced lymphocyte stimulation test (DLST) and the leukocyte migration test (LMT) can detect the presence of drug-sensitized T cells. However, these tests do not have a definite role in the diagnosis of DILD. This study explores the potential of these new tests and other similar tests in the diagnosis of DILD and provides a review of the relevant literature on this topic.

Therapeutic effects of the oriental herbal medicine Sho-saiko-to on liver cirrhosis and carcinoma

The traditional Chinese herbal medicine Sho-saiko-to is a mixture of seven herbal preparations that has long been used in the treatment of chronic liver disease. Various clinical trials have shown that Sho-saiko-to protects against the development of hepatocellular carcinoma in cirrhotic patients. However, the mechanism by which Sho-saiko-to protects hepatocytes against hepatic fibrosis and carcinoma is not yet known. Basic science studies have demonstrated that Sho-saiko-to reduces hepatocyte necrosis and enhances liver function. Sho-saiko-to significantly inhibits hepatic fibrosis by inhibiting the activation of stellate cells, the major producers of collagen in the liver, as well as by inhibiting hepatic lipid peroxidation, promoting matrix degradation, and suppressing extracellular matrix (ECM) accumulation. Furthermore, clinical trials have shown that Sho-saiko-to lowers the rate of hepatocellular carcinoma (HCC) development in patients with cirrhosis and increases the survival of patients with HCC. Unfortunately, some case reports have shown the side effects of Sho-saiko-to. Most of the side effects were interstitial pneumonia and acute respiratory failure induced by Sho-saiko-to in Japan. As a result of analyzing these case reports, the incidence and risk are increased by co-administration of interferon, duration of medication, and, high in an elderly population. This review discusses the properties of Sho-saiko-to with regards to the treatment of chronic liver diseases and suggests the side effects of Sho-saiko-to.

Diffuse interstitial infiltrative lung metastasis of malignant melanoma: a case report

A diffuse interstitial infiltrative pattern of lung metastasis in a patient with malignant melanoma is rare and can be confused with benign conditions such as pulmonary edema or drug-induced pneumonitis. We experienced a case of diffuse interstitial infiltrative lung metastasis in malignant melanoma in a 37-year-old man. This case was confirmed by a transbronchial lung biopsy. We herein describe the findings on CT and positron emission tomography scan.

Pleuropulmonary Changes Induced by Drugs in Patients with Hematologic Diseases

Patients with hematologic diseases who are being treated with therapy drugs, or receive radiation therapy or blood transfusions may develop a host of potentially fatal infectious and noninfectious pulmonary complications [1]. The increased complexity of multimodality and high-dose treatment regimens with the intended benefit of augmented antineoplastic efficacy and prolonged disease-free survival, the use of a panel of novel drugs to treat malignant and nonmalignant hematologic conditions (e.g., azacytidine, bortezomib, cladribine, dasatinib, fludarabine, imatinib, lenalidomide, rituximab, and thalidomide), total body irradiation (TBI) and hematopietic stem cell transplantation (HSCT) have increased the incidence of severe sometimes life-threatening pulmonary complications.

Prospective evaluation of drug-induced lung toxicity with high-resolution CT and transbronchial biopsy

PURPOSE

This study compared the results of high-resolution computed tomography (HRCT) and cytohistology after transbronchial biopsy in the evaluation of drug-related interstitial lung disease (DR-ILD).

MATERIALS AND METHODS

Patients with a clinical and imaging diagnosis of DR-ILD were prospectively included in a study protocol lasting 5 years. All patients were evaluated by bronchoscopy with transbronchial biopsy or bronchoalveolar lavage (BAL) following an HRCT examination that raised a suspicion of DR-ILD. Two radiologists (one senior and one junior), unaware of the diagnosis, reported the single HRCT findings, their distribution and predominant pattern. In the event of disagreement, the diagnosis was subsequently reached by consensus. Cytohistological examination was considered the gold standard in the diagnosis of DR-ILD. Patients who were unable to undergo the endoscopic procedure were excluded from the study.

RESULTS

The study included 42 patients (25 men, 17 women; age range 20-84 years). Transbronchial biopsy was performed in all but four patients (one case of alveolar haemorrhage and three cases of lipoid pneumonia) in whom the diagnosis was established with BAL. Assessment of the HRCT images revealed the following patterns: noncardiogenic pulmonary oedema (n=13); organising pneumonia (OP) (n=9); hypersensitivity pneumonitis (HP) (n=2); alveolar haemorrhage (AH) (n=2); nonspecific interstitial pneumonia (NSIP) (n=5); lipoid pneumonia (LP) (n=1); sarcoid-like pattern (n=1). Cytohistological diagnosis revealed diffuse alveolar damage (DAD) in 11 patients, OP in seven, HP in three, AH in three, chronic interstitial pneumonia (CIP) in eight, LP in three and pseudosarcoidosis in one. Subdivision of the drugs into antineoplastic and nonantineoplastic agents showed that the most common patterns were CIP (n=6), DAD (n=2) and OP (n=2) in the antineoplastic group and DAD (n=9) and OP (n=5) in the nonantineoplastic group. Sensitivity and specificity of the radiological analysis was excellent, especially for patterns such as OP and DAD (sensitivity 0.86 and specificity 0.88 for OP; sensitivity 1 and specificity 0.93 for DAD).

CONCLUSIONS

HRCT demonstrated excellent sensitivity and specificity. In cases in which its specificity was low, HRCT was nonetheless useful for biopsy planning and clinical-radiological monitoring after discontinuation of the drug treatment.

A case of adalimumab-associated interstitial pneumonia with rheumatoid arthritis

A 64-year-old woman with rheumatoid arthritis (RA) began to complain of recurrent non-productive cough 5 months after starting adalimumab. The chest radiograph and high-resolution computed tomographic findings revealed diffuse ground-glass attenuation. Her clinical course suggested that interstitial pneumonia (IP) may have been induced by adalimumab, and she was successfully treated with a medium dose of corticosteroid. This case indicates that adalimumab-associated IP should be considered if a RA patient develops non-productive cough following adalimumab therapy.

Reversible lansoprazole-induced interstitial lung disease showing improvement after drug cessation

Lansoprazole is an acid proton-pump inhibiting drug that is used for the treatment of duodenal or gastric ulcers, H. pylori infection, gastroesophageal reflux disease or Zollinger-Ellison syndrome. Although lansoprazole is well known for its gastrointestinal and dermatologic adverse effects, mild pulmonary symptoms are also known to develop from taking this drug. There have been no reports about lansoprazole-induced interstitial lung disease. We report here a case of lansoprazole-induced interstitial lung disease that developed in a 66-year-old man.

Pulmonary complications of connective tissue diseases

Lung involvement is common in patients who have complications of connective tissue disease (CTDs) and causes considerable morbidity and mortality. High resolution CT (HRCT) has a pivotal role in the detection of lung fibrosis. In patients who have coexistent pathologic processes, HRCT often allows the predominant process to be identified. HRCT has an important role in detecting possible complications such as opportunistic infection or the development of malignancy. However, the limitations of HRCT should not be overlooked. In many cases, HRCT appearances are nonspecific and may or may not be related to an underlying CTD. Thus, radiologic findings should never be interpreted without knowledge of the clinical picture.

High-resolution computed tomography patterns and immunopathogenetic findings in drug-induced pneumonitis

We tried to determine whether high-resolution computed tomography (HRCT) patterns correlate with the immunopathogenetic findings and whether they could provide helpful information for predicting the outcomes in non-neoplastic drug-induced pneumonitis. The HRCT images were classified as most suggestive of pneumonitis, diffuse alveolar damage (DAD), non-specific interstitial pneumonia, organizing pneumonia (OP), hypersensitivity pneumonitis, and acute eosinophilic pneumonia (AEP) in 34 patients with non-neoplastic drug-induced pneumonitis. The patients were analyzed for the bronchoalveolar lavage (BAL) cell findings and for the circulating levels of interferon-inducible protein 10 (IP-10) and macrophage-derived chemokine (MDC), which were measured by an enzyme-linked immunosorbent assay. The cumulative dose of corticosteroids received by the patients and the day when they required supplemental oxygen were calculated as outcome markers. There were no differences in the circulating chemokine levels and the BAL cell profiles except for the eosinophil percentages among the HRCT patterns. Most of the cases with pulmonary eosinophilia belonged to the OP and AEP groups, and the circulating MDC levels correlated with BAL eosinophil percentages. We could not find any relationship between the BAL cell profiles or the chemokine levels and the outcome markers. In contrast, the HRCT patterns rather predicted the outcomes because larger cumulative dose of steroids and longer oxygen supply were required for the patients in the DAD and OP groups. In contrast, all patients with AEP recovered without steroid administration. The present study suggests that HRCT does not predict cellular pathophysiology but it may predict the corticosteroid use in non-neoplastic drug-induced pneumonitis.

Increased pulmonary FDG uptake in bleomycin-associated pneumonitis

BACKGROUND

Bleomycin is an antineoplastic agent that is mainly used in combination regimens. Dose-limiting toxicity is the bleomycin-induced pneumonitis (BIP) that can be diagnosed by clinical and radiological findings. The early diagnosis of BIP is often challenging.

CASE REPORT

We report the occurrence of a diffuse pulmonary increase of FDG uptake in the FDG-PET scan in association with suspected BIP in a patient treated for relapsed seminoma. A retroperitoneal relapse was treated with a combination chemotherapy containing cisplatin, etoposide, and bleomycin. After 3 cycles of this regimen the patient developed mild clinical signs of early BIP. A following FDG-PET in order to evaluate treatment response showed a diffuse increased FDG uptake of the right lung. The subsequent HRCT revealed pathological findings consistent with BIP. After cessation of bleomycin and a systemic steroid trial a prompt normalization of the abnormal radiological and clinical findings occurred together with a disappearance of the increased pulmonary FDG uptake.

CONCLUSION

FDG-PET can be used for evaluation of residual disease in patients treated for advanced seminoma. In cases of otherwise unexplained increased pulmonary FDG uptake in patients under treatment with bleomycin an evaluation for early BIP as a possible cause of this finding is warranted.

Interstitial lung disease in patients with non-small-cell lung cancer treated with epidermal growth factor receptor inhibitors

Interstitial lung disease (ILD) refers to a diverse range of pulmonary fibrotic disorders and may be hard to accurately diagnose, as distinguishing it from other pulmonary diseases can be difficult. Estimations of the incidence in populations are confounded by the complexity of the different forms of the disorder. In addition, ILD is a comorbid disease of lung cancer and is seen after most forms of chemotherapy and radiotherapy for advanced lung cancer. Incidences of >or=10% have been reported; however, whatever the true incidence, both chemotherapy and radiotherapy enhance the risk of developing ILD. ILD has also been reported with the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors, including erlotinib (Tarceva, OSI-774) and gefitinib (IRESSA). In a large number of gefitinib-treated patients (n > 185,000) an incidence of approx 1% has been observed (approx 2% in Japan; 0.3% in the rest of the world). Nevertheless, as with other treatments for advanced non-small-cell lung cancer, the clinical benefit outweighs the risk of ILD. In this article, we review the data on ILD with EGFR inhibitors and other common lung cancer treatments.

Drug-induced lung diseases: most common reaction patterns and corresponding high-resolution CT manifestations

Drug-induced lung disease is an increasingly common cause of morbidity and mortality. The diagnosis is based on clinical history and consistent radiologic findings. Lung biopsy is performed in a small percentage of cases. High-resolution CT may demonstrate parenchymal abnormalities in patients with normal radiographs and provides a better depiction of the pattern and distribution of findings. Knowledge of the most common high-resolution CT manifestations and the corresponding histologic patterns is important for early recognition and proper management of drug-induced lung disease.

Mefloquine-induced pneumonitis

Mefloquine is indicated as oral treatment and as prophylaxis for malaria in areas where chloroquine-resistant malaria is present. Gastrointestinal and neuropsychiatric side effects of mefloquine are well known. More severe neuropsychiatric disorders such as psychosis, depression, hallucinations, and seizures are also reported in the literature. We are reporting a case of drug-induced pneumonia due to mefloquine. This diagnosis was confirmed 4 months after the adverse event, after restarting the same malaria prophylaxis, which could be considered as an unintentional provocation test. This is the third case report in the literature of acute lung injury caused by mefloquine.