Amiodarone-Induced Pulmonary Toxicity - A Frequently Missed Complication.

INTRODUCTION: Amiodarone is often used in the suppression of tachyarrhythmias. One of the more serious adverse effects includes amiodarone pulmonary toxicity (APT). Several pulmonary diseases can manifest including interstitial pneumonitis, organizing pneumonia, acute respiratory distress syndrome, diffuse alveolar hemorrhage, pulmonary nodules or masses, and pleural effusion. Incidence of APT varies from 5-15% and is correlated to dosage, age of the patient, and preexisting lung disease. DESCRIPTION: A 56-year-old male with a past medical history of coronary artery disease and chronic obstructive pulmonary disease was admitted for a coronary artery bypass graft. Post-operatively, the patient was admitted to the ICU for ventilator management and continued to receive his home dose of amiodarone 400 mg orally twice daily, which he had been taking for the past 3 months. The patient was found to be hypoxemic with a PaO2 52 mmHg and bilateral infiltrates on chest x-ray. Patient also complained of new onset dyspnea. Physical exam found bilateral rhonchi with bibasilar crackles and subcutaneous emphysema along the left anterior chest wall. Daily chest x-rays showed worsening of bilateral interstitial infiltrates and pleural effusions. A chest high-resolution computed tomography on post-operative day 3 showed extensive and severe bilateral ground glass opacities. APT was suspected and amiodarone was discontinued. A course of oral prednisone without antibiotics was initiated, and after one week of treatment the chest film cleared, the PaO2 value normalized and dyspnea resolved. DISCUSSION: APT occurs via cytotoxic T cells and indirectly by immunological reaction. Typically the lungs manifest a diffuse interstitial pneumonitis with varying degrees of fibrosis. Infiltrates with a 'ground-glass' appearance appreciated on HRCT are more definitive than chest x-ray. Pulmonary nodules can be seen, frequently in the upper lobes. These are postulated to be accumulations of amiodarone in areas of previous inflammation. Those undergoing major cardiothoracic surgery are known to be predisposed to APT. Some elements require consideration: a baseline pulmonary function test (PFT) did not exist prior. APT would manifest a restrictive pattern of PFTs. In APT diffusing capacity (DLCO) is generally >20 percent from baseline. A DLCO was not done in this patient. Therefore, not every type of interstitial lung disease could be ruled out. Key features support a clinical diagnosis: (1) new dyspnea, (2) exclusion of lung infection, (3) exclusion of heart failure, (4) new radiographic features, (5) improvement with withdrawal of amiodarone. Our case illustrates consideration of APT in patients who have extensive use of amiodarone and new onset dyspnea.

Treatment of lisch corneal dystrophy with photorefractive keratectomy and mitomycin C.

PURPOSE: To describe a case of Lisch dystrophy; review the clinical, histopathologic, and electron microscopic features of this entity; and discuss a novel treatment approach using photorefractive keratectomy (PRK) and mitomycin C (MMC). METHODS: A 45-year-old man with a feathery, comet-shaped, right-sided, corneal lesion was treated with excimer laser PRK and 20 seconds of MMC. The uninvolved fellow eye underwent traditional PRK without the use of MMC. Epithelial scrapings were sent for histopathologic analysis. RESULTS: Histopathologic analysis showed vacuolated cells in the epithelial layer. Electron microscopy revealed empty intracytoplasmic vacuoles, electron-dense whorled inclusions, and reduced tonofilaments. Surface ablation and MMC was successful in treating the initial lesion, with only minimal recurrence noted in the affected eye. Surprisingly, a new asymptomatic lesion was noted in the unaffected eye but dissipated over time. CONCLUSIONS: Although the whorled inclusions represent a novel finding, the overall clinical and microscopic analysis was consistent with Lisch dystrophy. Surface ablation with MMC should be considered as a treatment option for this disease.

Intra-observer reproducibility and interobserver reliability of the radiographic parameters in the Spinal Deformity Study Group's AIS Radiographic Measurement Manual.

STUDY DESIGN: Retrospective cross-sectional assessment of the reproducibility and reliability of radiographic parameters. OBJECTIVE: To measure the intra-examiner and interexaminer reproducibility and reliability of salient radiographic features. SUMMARY OF BACKGROUND DATA: The management and treatment of adolescent idiopathic scoliosis (AIS) depends on accurate and reproducible radiographic measurements of the deformity. METHODS: Ten sets of radiographs were randomly selected from a sample of patients with AIS, with initial curves between 20 degrees and 45 degrees. Fourteen measures of the deformity were measured from posteroanterior and lateral radiographs by 2 examiners, and were repeated 5 times at intervals of 3-5 days. Intra-examiner and interexaminer differences were examined. The parameters include measures of curve size, spinal imbalance, sagittal kyphosis and alignment, maximum apical vertebral rotation, T1 tilt, spondylolysis/spondylolisthesis, and skeletal age. RESULTS: Intra-examiner reproducibility was generally excellent for parameters measured from the posteroanterior radiographs but only fair to good for parameters from the lateral radiographs, in which some landmarks were not clearly visible. Of the 13 parameters observed, 7 had excellent interobserver reliability. CONCLUSIONS: The measurements from the lateral radiograph were less reproducible and reliable and, thus, may not add value to the assessment of AIS. Taking additional measures encourages a systematic and comprehensive assessment of spinal radiographs.