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RSPT 2325: CP Diagnostics Notes: Clinical Application of Radiographic Techniques Good website for CXR films: http://www.meddean.luc.edu/lumen/MedEd/medicine/pulmonar/cxr/atlas/cxratlas_f.htm History of CXRAY The early part of the last century introduced medical workers to x-ray technology enabled practitioners to see the inside of the human body without cutting into it enabled them to identify disease that they couldn't identify through the history and physical exam Soon became a discipline within the field of medicine Production of the Radiograph electric current is generated by a transformer current passes through the focusing plates and arrives at the cathode Electrons are "boiled off" creating a cathode stream The stream strikes the anode target and is transformed into XRAY XRAY leaves the sealed vacuum tube through a window and strikes the patient it then passes through the patient and casts a shadow on the film cassette this creates a image on the film that has been put on the opposite side of the pt from the xray tube XRAYS don't reflect back like light but penetrate matter penetration is dependent on the density of the matter dense objects (bone) absorb more xray and allow less penetration As xray passes through the pt it is absorbed proportionate to the density of the material it passes through. air filled objects are fully penetrated and turn black (radiolucent) dense objects absorb some of the xray and appear less dark (radiopaque) these areas appear as white shadows on the film 4 densities seen on film: fat bone water air The distance of the patient from the xray tube is also important the closer the pt is to the source the greater magnification and distortion the pt should be about 6 feet from the xray tube for a conventional xray this creates good focus and less magnification Indications for the Chest XRAY Exam Used to: Detect alterations of the lungs due to disease determine appropriate therapy evaluate effectiveness of therapy determines positions and locations of tubes and catheters ETT (http://images.google.com/imgres?imgurl=http://www.hawaii.edu/medicin e/pediatrics/neoxray/neo02.jpg&imgrefurl=http://www.hawaii.edu/medici ne/pediatrics/neoxray/neoxray.html&h=600&w=600&sz=32&hl=en&start =25&sig2=xj_QdyHyOPIXNuawFX46A&tbnid=FOZ533zYwaHRQM:&tbnh=135&tbnw=135&ei=q d6tSLjbLKioeZaTiY8K&prev=/images%3Fq%3Dxray%2BETT%26start %3D20%26ndsp%3D20%26hl%3Den%26sa%3DN) UAC (umbilical artery catheters) http://images.google.com/imgres?imgurl=http://www.hawaii.edu/medicine/pe diatrics/neoxray/neo05.jpg&imgrefurl=http://www.hawaii.edu/medicine/pedia trics/neoxray/neoxray.html&h=522&w=341&sz=18&hl=en&start=9&sig2=W _ZKhl6yfAAfWIh9OZSG2Q&tbnid=5j8pF6mmB3Bg_M:&tbnh=131&tbnw =86&ei=Kt-tSOODJiievjG2KIK&prev=/images%3Fq%3Dxray%2Buac%26gbv%3D2%26hl% 3Den (3rd case study) NG tubes http://images.google.com/imgres?imgurl=http://www.qub.ac.uk/cskills/Nasog astric/xray.jpg&imgrefurl=http://www.qub.ac.uk/cskills/Nasogastric/Nasogast rictube_insertion.htm&h=532&w=450&sz=25&hl=en&start=6&sig2=IO7pGwhlCTAI6Hyk4fLIQ&tbnid=pMgQpd5kc7D2M:&tbnh=132&tbnw=112&ei=f9-tSP65D5geMGmjJgK&prev=/images%3Fq%3Dxray%2BNG%26gbv%3D2%26hl%3 Den Feeding tubes (Dopoff tubes), etc In the lung: http://images.google.com/imgres?imgurl=http://www.learningradiology.com/c aseofweek/caseoftheweekpix20071/cow285lg.jpg&imgrefurl=http://www.learningradiology.com/archives2007/ COW%2520285DHT%2520in%2520RLL/caseoftheweek285page.html&h=711&w=500&sz= 54&hl=en&start=8&sig2=RzsgLZ8dDQET4oLdii55aA&tbnid=LCaVGa5gfr Ro6M:&tbnh=140&tbnw=98&ei=sN- tSL_hD6HyebGRnacK&prev=/images%3Fq%3Dxray%2Bfeeding%2Btube% 26gbv%3D2%26hl%3Den Proper Position: (See PA cath) http://www.meddean.luc.edu/lumen/MedEd/medicine/pulmonar/cxr/atlas/cxra tlas_f.htm Observe progression of lung disease Remember that a stat chest film can be a lifesaving measure in some cases (pneumothorax) Due to the importance of chest films in the treatment and diagnoses of pulmonary issues all RT's should be very familiar with how to interpret CXRAYS. Radiographic Views Standard PA View Pt stands upright with their back to the xray tube and the anterior chest is pressed against the area where the film is held. Since the beam penetrates the back prior to the front this film is called a Posterioanterior (PA) film. Less magnification of the heart due to its location (anterior) in the chest http://www.imagingpathways.health.wa.gov.au/Includes/image/ari/dennis %20CXR%20PA.jpg Lateral View the pt is then turned to the side to obtain a lateral view Left lateral view is with the L side to the film most common lateral position provides less magnification of the heart Better view of the L lower lobe than the PA view because the heart shadow isn't there. If a Rt sided lesion is present a right lateral view would be used http://www.nzma.org.nz/journal/118-1227/1777/content02.jpg Special Views Lateral Decubitus View used for special problems taken with pt lying on the R or L side used to view free flowing fluid present in the chest small amounts (25-50 ml) can be seen with this technique pts with pleural effusions should be placed on the same side as the pleural effusion can also be used to view a pneumothorax pts with suspected pneumothorax should be placed on the side opposite of the pneumo Lateral Decubitus : http://images.google.com/imgres?imgurl=http://www.cdc.gov/ncidod /dvbid/dengue/slideset/set1/images/pleural-effusionindex.jpg&imgrefurl=http://www.cdc.gov/ncidod/dvbid/dengue/slides et/set1/vi/slide08.htm&h=382&w=475&sz=29&hl=en&start=1&sig2= qlL13lp9qZRN8yZc2Kubvg&tbnid=RrgBwvvuup8HCM:&tbnh=104&t bnw=129&ei=0OOtSLqwO4iueZ_ZvZ8K&prev=/images%3Fq%3Dx ray%2Blateral%2Bdecubitus%26gbv%3D2%26hl%3Den%26sa%3 DG Apical Lordotic View film made at a 45° angle to view the RML or the apical region of the lung this angle creates the shadows of the clavicles above the thorax http://www.mevis-research.de/~hhj/Lunge/imaAna/AnaLordTh37.JPG Oblique Views Helpful in viewing pulmonary or mediastinal lesions that you could not view on the PA and lateral film due to overlying structures. pt is turned 45° degrees to the R or L with the anterior portion of the chest toward the film http://images.google.com/imgres?imgurl=http://www.bcm.edu/radiology/c ases/pediatric/images/1c.jpg&imgrefurl=http://www.bcm.edu/radiology/ca ses/pediatric/text/1desc.htm&h=710&w=650&sz=21&hl=en&start=3&sig2=5C0bwJS4ClN wW0w83I4yoQ&tbnid=-uFb1CfgRhrBzM:&tbnh=140&tbnw=128&ei=JWtSMOWDIjeesPqhJAK&prev=/images%3Fq%3DOblique%2BView%2 Bchest%26gbv%3D2%26hl%3Den%26sa%3DG Variations with XRAY most are taken at full inspiration some are taken on exhalation for better viewing a small pneumo can be detected easier on exhalation When the lung volume is reduced the pleural air volume remains the same. The pneumothorax would now occupy more of the chest volume and shows up better. Also the lung is denser in the expiratory phase and the contrast of the air in the pneumo can be visualized easier. Film taken on exhalation: http://meded.ucsd.edu/isp/1994/imquiz/images/aortapa.jpg Portable Chest Film (AP View) most common used view in the ICU With the pt lying in bed, the film is placed behind the pts back and the beam is placed above them This film requires skill to interpret due to artifacts (common) not centered at an odd angle over or underexposed poor quality poor positioning of the pt Tell me what is wrong with the following xray: http://myweb.lsbu.ac.uk/dirt/museum/margaret/48--15131640481.jpg http://www1.umn.edu/eatef/images/fig6.gif (diaphragmatic hernia on the Left)http://royjacob.googlepages.com/Imagequiz2.jpg http://www.ispub.com/xml/journals/ijpn/vol4n1/vein-fig1.jpg Congenital lung lesions are relatively rare surgical conditions of the fetus and the newborn. There are several types (CCAM, sequestrations, bronchogenic cysts), which all can be small and insignificant, or become so large that they compress other organs in the chest. They can be found by accident in an otherwise healthy child (on a routine chest X-ray), but are now more and more often detected by ultrasound before birth.http://bms.brown.edu/pedisurg/images/ImageBank/Conge nLung/XRayLargeCCAM.jpg Sirenomelia (Mermaid Syndrome) in a Full-term Infant Sirenomelia, alternatively known as Mermaid Syndrome is a very rare congenital deformity in which the legs are fused together, giving the appearance of a mermaid. This condition is found in approximately one out of every 70,000 live births (about as rare as conjoined twins) and is usually fatal within a day or two of birth because of complications associated with abnormal kidney and bladder development and function. It results from a failure of normal vascular supply from the lower aorta in utero. Maternal diabetes is associated with caudal regression syndrome and sirenomelia, although this association is not generally accepted. (Note: multiple rib abnormalities, sacral agenesis, iliac hypoplasia, and single femur with two ossification centers). http://images.google.com/imgres?imgurl=http://www.natu re.com/jp/journal/v24/n5/images/7211085f2.jpg&imgrefurl =http://www.nature.com/jp/journal/v24/n5/fig_tab/72110 85f2.html&h=608&w=500&sz=64&hl=en&start=21&sig2= DC2DTtV3G2hm0WWxN4uqKQ&usg=__UfDljOxsx1NfXlp4Si IS9Lrfbms=&tbnid=kTTQFMgltKFPM:&tbnh=136&tbnw=112&ei=DMmuSO6IFpH2eaa JuIIB&prev=/images%3Fq%3Dinfant%2Bxray%26start%3 D20%26gbv%3D2%26ndsp%3D20%26hl%3Den%26sa%3 DN http://myweb.lsbu.ac.uk/dirt/museum/margaret/58--1611641220.jpg http://myweb.lsbu.ac.uk/dirt/museum/simon/515-1422gsd48.jpg Cardiology xray quiz: http://images.google.com/imgres?imgurl=http://myweb.lsbu.ac. uk/dirt/museum/margaret/58--1611641220.jpg&imgrefurl=http://myweb.lsbu.ac.uk/dirt/museum/ unkheart.html&h=834&w=571&sz=77&hl=en&start=1&sig2=eHp qZVvBr5irHVMMjuv8Ew&usg=__HuhNmeitLTQ0aacejgT8t ccRnYU=&tbnid=RzaBJjl5HuXgjM:&tbnh=144&tbnw=99&ei =38uuSO-BG6HyeevlZUB&prev=/images%3Fq%3Dsite:myweb.lsbu.ac.uk%2Binfa nt%2Bxray%26gbv%3D2%26ndsp%3D20%26hl%3Den extra shadows bedding gown leads tubing Used to evaluate lung status , tube positions, results from invasive procedures Post procedure CXR Tracheal Intubation Use an AP chest film Inferior tip of the ETT should be 3-5 cm above the carina RT or L mainstem intubation can be recognized immediately after intubation by Xray to reduce harm to the pt. unrecognized R or L mainstem can cause pneumothorax, shock, hypoxia and death manufacturer's of the ETT include a radiopaque line that runs the length of the tube to be easily seen on XRAY Post xray note the tubes position at the pts lips (or corner of the mouth) and record. http://www.meddean.luc.edu/lumen/MedEd/medicine/pulmonar/cxr/atlas/ cxratlas_f.htm Central Venous Pressure Line A CVP line is a special intravenous (IV) line. A CVP line may be used when a patient needs: • To have measurements taken that will help to determine the best treatment. • A large vein IV access to give fluids and/or medications. • A type of IV feeding called total parenteral nutrition (TPN). One section of this line may be used for monitoring (CVP monitoring) when patients are in the Intensive Care Unit (ICU), Intermediate Care Unit (IMCU), or Operating Room (OR). Sometimes, a patient on a regular nursing unit may need A CVP line or may have one after transfer from a special care unit. evaluation of the CVP ensures proper placement of the catheter tip catheter is placed in the R or L subclavian vein or jugular should rest in the junction of the superior vena cava and the R atrium of the heart common to cause pneumothorax due to chance of entering the lung after puncturing through the vein if fluid is delivered at this time it will fill the chest cavity SEE Figure 9-4 in Wilkens Figure 9-5 shows malposition of the catheter. This can be alleviated by placing pressure on the jugular vein with the pts head turned the opposite direction and slowing withdrawing the catheter. An AP film should be performed immediately following line placement prior to administering any fluids. Pulmonary Artery Catheter AKA Swan-Ganz Always use portable after insertion to confirm catheter placement These catheters are usually in place for lengthy time frames so a daily xray for position is vital good position is the R mid lung close to the hilum Placement of the Swan Ganz: A small balloon on the tip of the catheter is inflated (1 ml) after placement into the artery. It then is dragged by the blood flow through the: R atrium tricuspid valve R ventricle pulmonary valve comes to rest in the R pulmonary artery when it wedges into a smaller pulmonary capillary (viewed on pressure monitor) balloon is then deflated and a xray is obtained If catheter is in good placement it is sutured into place http://video.google.com/videosearch?q=Inserci%C3%B3n+SwanGanz%3A+Parte+II&hl=en&emb=0# NG tubes xray necessary after insertion to make sure it is located in the stomach or small bowel (not in the lung). causes severe coughing and dyspnea unless heavily sedated can cause pneumonia and pneumothorax http://www.qub.ac.uk/cskills/Nasogastric/xray.jpg Chest Tubes placed in the L or R thorax and attached to a drain system tube can be placed at bedside with conscious sedation tip of the tube should be posterior and near the apex of the lung periodic xray ensures the tube position is adequate and drainage is occuring http://www.meddean.luc.edu/lumen/MedEd/medicine/pulmonar/cxr/atlas/ cxratlas_f.htm Special Procedures Thoracentesis temporary placement of a needle into the pleural space to withdraw fluid for analysis after and before pictures: http://upload.wikimedia.org/wikipedia/commons/a/a6/Pneumonia_xray.jpg Pericardiocentesis Temporary placement of a needle into the sac surrounding the heart to draw off accumulated fluid for trx and analysis. Tomography Special xray where the tube is rotated throughout exposure above the pt. AKA body section roentgenography (roen-geno-graphy) used in the study of intrathorasic lesions that are obscured in standard x-rays due to overlying structures Computed Tomography provide a series of transverse (cross sectional) images of the body structures at multiple levels Each image represents a thin "slice" through the thorax to show what a particular level would look like Particularly helpful in detecting a masses size, shape, location and radio density In the lungs CT differentiates between pleural and parenchymal masses detects pulmonary nodules detects subpleural lesions not visible on a standard film shows clear patterns of abnormalities stages bronchogenic carcinoma Needle biopsy of pulmonary and mediastinal masses can be directed through the use of CT guidance of needle placement. So sensitive that lesions can be identified without the pt ever having had symptoms Lung Tumors used to determine if a lesion outside the chest has spread to the lung Can detect nodules as small as 2-3 mm One lesion has been found - CT guides the biopsy needle to the lesion Chronic Interstitial Disease Can see considerable differences in these pts between a standard xray read as "normal" and a CT scan. More than 100 diseases involve the lung interstitium AIDS useful in seeing large lymph nodes, abscesses and cavities that might otherwise be missed Occupational Lung Disease Lung disease that results from inhalation of dust, fumes, irritant gases, organisms and smoke are called extrinsic alveolitits. can lead to asthma and pulmonary fibrosis CT helps easily identify changes in the pleura and parenchyma such as Pneumonia excellent imaging of changes in the hila and pleura opportunistic pneumonias are seen earlier than standard xray Bronchiectasis CT replaced the bronchogram for diagnosing bronchiectasis COPD diagnosis with standard xray is 65-80% With CT - 90% MRI Detects the radio signal emitted with hydrogen nuclei in the body are placed within a magnetic field and stimulated by radio waves. Is inferior to CT imaging in the case of intrapulmonary disorders effective in the study of lesions in the hilar or mediastinal regions helps determine hilar lymph node enlargements from enlarged blood vessels inoperable if the CA has spread enlarged the hilum most effective with vascular disorders such as Lung Scanning used in the evaluation of a possible pulmonary embolism image generated by radiation emitted from radioisotopes introduced into the lungs measure the volume and distribution of ventilation and perfusion in the lung Two methods: 1. Perfusion Lung Scan - albumin particles are tagged with a radioactive marker and injected into the vein as it passes through the lung some of the tagged particles will settle into the small pulmonary capillaries a scan is passed over the chest and the pattern shown on the image shows the distribution and volume of lung perfusion A reduction in pulmonary blood flow due to an embolism, atelectasis or pneumonia will show due to a reduction of radioactivity in that area on the produced image. 2. Ventilation Lung Scan - pt breathes in a radioactive gas poorly ventilated areas will show easily due to the radioactive material's inability to enter that area Ventilation scan is then compared to the perfusion scan to identify the matching of ventilation to perfusion. embolism Results are often inconclusive PET Scan used to diagnose and stage cancers PET is a type of nuclear medicine imaging that uses very small amounts of radioactive material to diagnose or treat disease by the use radioactive materials called radiotracers. The radiotracer is injected into a vein, swallowed by mouth or inhaled as a gas and eventually collects in the area of the body being examined, where it gives off energy in the form of gamma rays. This energy is detected by the PET scanner. With the use of a computer to assist in the measurement of the amount of radiotracer absorbed by the body it then produces an image on both the structure and function of organs and other internal body parts. PET scans are used to: detect cancer determine how much a cancer has spread in the body assess the effectiveness of a treatment plan, such as cancer therapy determine if a cancer has returned after treatment determine blood flow to the heart muscle determine the effects of a heart attack, or myocardial infarction, on areas of the heart Identify areas of the heart muscle that would benefit from a procedure such as angioplasty or coronary artery bypass surgery (in combination with a myocardial perfusion scan). evaluate brain abnormalities, such as tumors, memory disorders and seizures and other central nervous system disorders to map normal human brain and heart function Due to malignant cells having high metabolic rates these cells will pick up or absorb the radioactive material. These areas will "light up" when the PET scan is used producing a bright spot on the film Pulmonary Angiography done to evaluate thromboembolic disuse in the lung performed when results from a V/Q scan are uncertain contrast is injected into the pulmonary artery and xray is taken http://www.leadershipmedica.com/scientifico/scieott03/scientificaita/8imperat ore/imperatore_fig2.gif Evaluation of the Xray Clinical Findings review pt Hx and exam before viewing chest film to have a better understanding of what you may be looking for Placing the Film on the View Box place as if the pt is facing you The L side of the chest is discernable by the heart The letters "L" and "R" are commonly found on the film check the nameplate to identify correct pt adequacy of exposure is judged by the vertebrae showing through the heart shadow Make sure the film wasn't rotated when it was obtained http://coursewareobjects.elsevier.com/objects/elr/Wilkins/assessment5 e/IC/pdfs/009017.pdf The degree of the pts inspiratory effort is assessed by counting posterior ribs above the diaphragm. On a PA film, 10 ribs indicate good effort More than 10 would indicate hyperinflation Ask these questions: Interpretation Normal lung tissue has low density If there is consolidation (increased density) because of disease (tumor, pneumonia) the area will absorb more xray and appear white on the film Abnormalities that decrease lung density (cavities, blebs) appear darker due to not absorbing xray Heart, diaphragm, and vessel are considered to have the density of water more dense than air Structures in the chest are the most dense (bones, ribs, clavicles, etc) Remember to look at the bony areas first, followed by the soft tissues and then the organs Silhouette Sign - obliteration of normally seen differences in structures on film Air Bronchogram - when the bronchi (usually invisible) are surrounded by consolidation they become visible http://www.med.yale.edu/intmed/cardio/imaging/findings/air_bronchogra m/graphics/rad1.gif Limitations lesions in blind areas or very small lesions may not be seen on xray xray can be normal in very sick resp pts Clinical and Radiographic findings in Lung Diseases familiarity with common respiratory disorders is helpful in interpreting chest films Atelectasis Compressive Atelectasis Obstructive Atelectasis CXR is the easiest way to see loss of lung volume by atelectasis Subtle signs of collapse due to atelectasis: Shift of the fissure lines toward the collapsed area Fissures separate the upper, middle and lower lobes by horizontal and oblique fissures. Anteriorly the horizontal fissure runs from the 4th rib at the sternum to the 5th rib midaxillary. The oblique fissure runs laterally from the 6-7th rib in the midclavicular line to the 5th rib at the midaxillary line. The Left lung is separated into the upper and lower lobes by the oblique fissure. Anteriorly it runs laterally form the 67th rib and the midclavicular line to the 5th rib midaxillary line. Movement of the hilum toward the collapsed area Complete loss of volume in one lung Hemidiaphragm elevation Pneumothorax the presence of air within the pleural cavity Air can gain entrance through the chest wall, diaphragm, mediastinum, or from the lung through the visceral pleura Small pneumo seen easily with end-expiration film Tension Pneumothorax A hole in the lung has formed a flap that acts as a one way valve. It allows air to enter the pleural space but not leave Pressure eventually shifts the heart away form the involved lung and puts pressure on the healthy one causing it to not function effectively Trachea will shift toward the affected side Tension pneumo are predisposed by the following: Physical signs of pneumo without tension: reduced chest wall movement on the side of the pneumo loss of breath sounds on the side of the pneumo increased resonance on that side tachycardia and tachypnea cyanosis, external wound, bruising, sucking noise on affected side (-) whispered sounds on affected side Hyperinflation most common cause is obstructive lung disease CXR will show over time consistent changes that are found with the disease process (COPD) Normal CXR may be found is the disease is in the mild stages With COPD you may see on film: http://myweb.lsbu.ac.uk/dirt/museum/simon/533-172-gsa25.jpg enlarged intercostal spaces Other changes with COPD Hyperinflation: http://meded.ucsd.edu/clinicalmed/thorax-xray-increasedap.jpg flat diaphragms with increased tanslucency of the lung Air Trapping due to decreased ability to exhale easily seen on an end expiratory film Loss of interstitial tissue and pulmonary vessels due to lung destruction Increased lung markings caused by bronchial wall inflammation and thickening commonly seen with chronic bronchitis, CF, and bronchiectasis http://myweb.lsbu.ac.uk/dirt/museum/margaret/68--219-2081331.jpg Interstitial Lung Disease Diseases listed in Box 9-2 on page 184 Process associated with pulmonary fibrosis: Most fibrotic lesions form in the lower lung fields. An alveolar pattern is seen when alveoli begin to fill up with blood, pus, protein, or cells. Air Bronchograms may be seen with alveolar pattern. Congestive Heart Failure: http://www.med.yale.edu/intmed/cardio/imaging/findings/air_bronchogra m2/graphics/rad1.gif Chest x-ray reveals redistribution of pulmonary vasculature to the upper lobes. The width of the heart shadow exceeds half the width of the thorax on the chest film. Pleural Effusion Lateral decubitus useful for recognition of small pleural effusions http://myweb.lsbu.ac.uk/dirt/museum/margaret/68--211c-1321350.jpg Consolidation http://upload.wikimedia.org/wikipedia/commons/thumb/5/53/Xray_lung_consolidation.jpg/728px-X-ray_lung_consolidation.jpg SUMMARY: Through the readings and discussions in this chapter, we have learned that there are a wide variety of imaging devices available. Cost, availability, patient condition, type of disease, and desired information must be taken into consideration when selecting the most appropriate imaging device. Of all the imaging devices, chest radiographs are the most widely used. They provide an effective, inexpensive, and convenient means of furthering the respiratory therapist’s evaluation of the patient. The chest radiograph is an efficient tool that enables the respiratory therapist to view anatomic structures, look for evidence of disease, evaluate therapeutic modalities, and view the progression of a disease. Fundamental interpretation of the chest film calls for a systematic review of all structures seen on the chest x-ray. Abnormalities in the lung associated with specific lung diseases often show characteristic patterns on the chest x-ray. Recognition of these patterns helps determine the underlying disease that causes a patient to seek medical help. Xray Case Study #1: On the evening of October 22, a 59-year-old Caucasian man, contract employee at a U.S. State Department mail sorting facility that received mail from the District of Columbia postal facility associated with cases 3, 4, 5, and 6, became ill. He had drenching sweats, followed over the next 2 days by fatigue, severe myalgias, subjective fever, chills, headache, nausea, vomiting, abdominal pain, cough with scant white sputum, and substernal chest pain. He had no dyspnea or diarrhea. When he arrived at a local emergency room on October 24, temperature was 38.2°C, and heart rate 116/min, and respiratory rate and blood pressure were normal. A complete blood count was normal, and serum electrolytes showed hyponatremia and hypokalemia (Table 1). His past medical history was unremarkable, and he did not smoke. A chest X-ray was initially reported as normal. The patient was thought to have a viral syndrome and was discharged, but blood cultures were obtained and ciprofloxacin was prescribed. He took one dose that night, but vomiting, fatigue, and headache worsened. He also reported transient distortion in his left visual field, and his wife reported that he was intermittently confused. Blood cultures grew gram-positive bacilli after 17 hours of incubation; therefore, on October 25, he was called back to the hospital for admission. The blood isolate was subsequently identified as B. anthracis. At admission, his vital signs were as follows: temperature 38.2°C, heart rate 108/min, respiratory rate 20/min, blood pressure 121/60 mm Hg, and oxygen saturation 94% on room air. He appeared ill and had decreased breath sounds at the right base. The rest of the examination was unremarkable. Laboratory studies on admission included WBC count 9,500/mm 3 with 81% segmented neutrophils, 9% lymphocytes, and 9% monocytes, hematocrit 48.1%, platelet count 196,000/ mm3, normal electrolytes and creatinine, SGOT 85 IU/L, SGPT 64 IU/L, alkaline phosphatase 141 IU/L, bilirubin 1.6 mg/dL, and albumin 3.0 mg/dL. On review, the initial chest X-ray showed mediastinal widening (Figure 5), and chest CT on the day of admission showed mediastinal adenopathy with evidence of hemorrhage, normal lung parenchyma, small bilateral pleural effusions, and a suspected small pericardial effusion (Figure 6). Intravenous penicillin and rifampin were added to the ciprofloxacin. His temperature rose to 39°C. Subsequently, vancomycin was added and penicillin was discontinued. On October 26, gastrointestinal bleeding developed, which required blood transfusion, endoscopic injection, and cautery of gastric and duodenal ulcers. On October 27, atrial fibrillation with variable ventricular response developed. On October 28, fever reached a maximum of 39.4°C and then decreased to 38.3°C. On October 30, WBC peaked at 31,300/mm3. On October 31, enlargement of the right pleural effusion required thoracentesis and removal of 900 cc of serosanguinous fluid (Table 1). The patient was discharged from the hospital on November 9. XRAY: http://www.medscape.com/content/2001/00/41/82/418214/art-e0706.04.fig5.jpg Case 2 On September 24, a 73-year-old Hispanic man, the newspaper mailroom clerk who delivered mail to the patient in Case 1, had onset of fatigue. On September 28, nonproductive cough, intermittent fever, rhinorrhea, and conjunctivitis developed. From September 28 to October 1, he had gradual progression of cough, marked worsening of fatigue with lethargy, onset of exertional dyspnea, fever, and sweats. He had mild abdominal pain associated with vomiting, and his coworkers and family noted intermittent periods of confusion. He had no underlying chronic illnesses, with the exception of a transient ischemic attack in August 2001. He did not smoke. He was admitted to the hospital on October 1. Temperature was 38.5°C, heart rate 109/min, respiratory rate 20/min, and blood pressure 108/61 mm Hg. He had bilateral conjunctival injection and bilateral pulmonary rhonchi. Examination, including assessment of neurologic function, was otherwise unremarkable. No skin lesions were observed. Admission laboratory results included normal WBC count and serum chemistries, except for hypoalbuminemia, elevated hepatic transaminases, borderline hyponatremia, and increased creatinine. Arterial blood gas values showed hypoxia (Table 1). Blood cultures obtained on hospital day 2, after initiation of antibiotics, showed no growth. A chest X-ray showed left upper and lower lobe infiltrates consistent with pneumonia and a small left pleural effusion (Figure 3). (click image to zoom) Figure 3. Chest X-ray (Case 2) showing diffuse consolidation consistent with pneumonia throughout the left lung. There is no evidence of mediastinal widening. No mediastinal widening was observed. The patient was initially given intravenous azithromycin; cefotaxime and ciprofloxacin were subsequently added. A nasal swab obtained on October 5 grew B. anthracis. Computed tomography (CT) of the chest showed bilateral effusions and multilobar pulmonary consolidation but no significant mediastinal lymphadenopathy (Figure 4). A left thoracentesis yielded serosanguinous fluid (Table 1) positive for B. anthracis DNA by PCR. Bronchoscopy showed bloody secretions in the right lower lobe and left lung, with severe mucosal hyperemia, mottling, and inflammation. Bacterial cultures of bronchial washings and pleural fluid did not grow. A transbronchial biopsy showed B. anthracis capsule and cell-wall antigens by immunohistochemical staining. Tests for Legionella spp., acid-fast bacteria, Pneumocystis carinii, Chlamydia spp., Leptospira, and Hantavirus and other viral pathogens were negative. The hospital course included an episode of supraventricular tachycardia with hypotension, maximum WBC count 26,800/ mm 3, and recurrent left pleural effusion that required repeat thoracentesis and placement of a chest tube. The pleural fluid from the second thoracentesis was positive for B. anthracis DNA by PCR. A pleural fluid cytology preparation and pleural biopsy showed B. anthracis capsule and cell-wall antigens by immunohistochemical staining. In addition, serial serum samples demonstrated a >4-fold rise in levels of serum antibody (IgG) to the PA component of the anthrax toxins by enzyme-linked immunosorbent assay (ELISA). The patient's condition gradually improved, and he was discharged from the hospital October 23 on oral ciprofloxacin. (click image to zoom) Figure 4. Computed tomography of chest (Case 2) showing bilateral pulmonary consolidation and pleural effusions. (click image to zoom) Figure 5. Chest X-ray (Case 7) showing mediastinal widening and a small left pleural effusion. Case study website: http://images.google.com/imgres?imgurl=http://www.medscape.com/content/2001/00/41/ 82/418214/arte0706.04.fig5.jpg&imgrefurl=http://www.medscape.com/viewarticle/418214_3&h=309 &w=400&sz=14&hl=en&start=6&sig2=fpw2UX232Whpm0wVixLEig&usg=__XOEak x-UPGjijwReEf7e7NF1Wg=&tbnid=jBRyef6njnmPsM:&tbnh=96&tbnw=124&ei=VtCuSOjQEZXWevynyZk B&prev=/images%3Fq%3Dxray%2Bpericardiocentesis%26gbv%3D2%26hl%3Den%26 sa%3DG