英文ppt课件casebased

Case Based Review- Lab 6 Robert Allan, MD Case #1 65 year old male with a past medical history of chronic obstructive pneumonia disease (COPD) presents with a one week history of worsening shortness of breath and fever. On physical examination he appears somewhat blue and he complains of constant sputum production- however now his sputum is more green than usual. He has diminished breath sounds over the left lower lung. He smokes 2 packs a day and has done so for the last 20 years. A chest x-ray shows a hyper-expanded “barrel like” chest with an infiltrate in the left lower lobe and an associated pleural effusion What is the most likely diagnosis? - COPD with superimposed PNEUMONIA, chronic bronchitis predominant (blue bloater) Case #1- COPD with fever What are the most likely organisms responsible? Streptococcus pneumoniae Haemophilus influenzae Moraxella catarrhalis Staphylococcus aureus Influenza could be considered but the infiltrate is focal- same could be argued for mycoplasma (focality and presence of significant fever would argue against) Case #1- COPD with fever Additional history may be of value. Below are additional questions that you could ask- think about how this may help you in the differential. Alcohol use/ abuse? - This could help identify risk factor for aspiration pneumonia due to impaired consciousness Social history/ sick contacts/ exposures? -Is he homeless and/ or exposed to possible M Tb? Have others had a similar illness -What is his occupation? Exposure to water may be important for considering Legionella Travel history? - Though perhaps not as relevant in this case- travel to regions with endemic fungal infections may suggest an etiology Case #1 COPD with fever On the subject of travel Match up the endemic fungus with the geographic area mentioned - Coccidiomycosis Southwestern US- California San Joaquin Valley Ohio and Mississippi river valley - A bit of a trick question here- Histoplasmosis and Blastomycosis have significant overlap geographically and both are in the Ohio- Mississippi river valley This fungal organism discussed in class has no particular geographic distribution - Another tricky question Cryptococcus should have come to mind immediately- however, in addition Pneumocystis, Aspergillus and Zygomycetes dont have an endemic area as well Case #1 COPD with fever Pulmonary function tests are performed, which of the following lines would best match the patients most likely pattern (green normal, black case #1 patient): Volume (L) Time (seconds) 1 Volume (L) Time (seconds) 1 Volume (L) Time (seconds) 1 A B C A- this shows an obstructive pattern with decreased FEV1 (correct answer); B shows a restrictive pattern- FEV1 is normal- FVC is significantly decreased; C shows a crazy pattern- maybe someone breathing through a slowing expanding straw Case #1- COPD with fever The resident physician decides to perform a therapeutic pleurocentesis. Being the overzealous medical student type you enthusiastically volunteer to perform the procedure. After you insert the fairly large needle the patient complains of being significantly short of breath and asks if you have ever done this before. Before you can answer he collapses. The aforementioned supervising resident is not around. You grab your stethoscope and listen for breath sounds but dont hear any on the side where you inserted the needle. What most likely happened? -It is very likely that the patient has developed a iatrogenic pneumothorax; not sure you could tell from the information above whether or not this is a tension pneumothorax. -Iatrogenic is a fancy means that means it was caused by medical intervention/ treatment - you likely inserted the needle into the patients lung and made a hole. Case #1- COPD with fever The resident still hasnt returned (long line at Opus coffee). You realize that a chest tube will likely benefit this patient- fortunately you find the appropriate materials and a book “Inserting Chest Tubes for Dummies” in the patients room. You succeed in stabilizing the patient and now have some of the fluid from the pleural space. You send this for testing to the lab with the following results you can trust these results because of the excellent job pathologists do in overseeing the quality of clinical laboratory testing: Pleural fluid protein: 8 g/ dL Serum protein: 7 g/dL Pleural fluid LDH: 223 Serum LDH: 200 IU/L (ref range 105 - 333 IU/L What type of effusion is this? -This is very likely a exudative (inflammatory) effusion - The ratio of the pleural fluid protein to serum protein= 8 g/dl / 7 g/dL= 1.1 - The ratio of the pleural fluid LDH to serum LDH= 223 IU/L / 200 IU/L= 1.1 - The pleural fluid LDH is just greater than 2/3 of upper limit of normal 333x 2/3= 222 is 2/3 upper limit of normal- patient is 223. Case #1- COPD with fever The patient is treated for pneumonia with “the appropriate antibiotic” and the infiltrate and pleural effusion diminish in size somewhat. However, on follow-up CT scan (performed to see if the effusion and infiltrate is clearing) the radiologists remarks that there may be a exophytic mass in the mainstem bronchus leading to the area of pneumonia. Bronchoscopy is performed which confirms the presence of an exophytic tumor mass a small biopsy (FYI- most biopsies pathologists get are small) is performed and the result is shown on the next slide. Case #1- COPD with fever Since you enjoyed the systemic pathology course so much (and the lung section in particular) you rush down to pathology the next morning and review the slides before the attending pathologist has a chance to look at them. The biopsy shows a mass composed of small clusters of cells with pink cytoplasm, round nuclei and speckled nuclear chromatin. You do not see any mitotic figures or necrosis. You decide that immunohistochemical stains may help you make the diagnosis what are two immunohistochemical stains that may be helpful? (NEXT SLIDE) Case #1- COPD with fever You order the following: Synaptophysin Chromogranin Later in the day these are completed the Synaptophysin and Chromogranin are all POSITIVE. The attending pathologist reviewing lung cases that day shows up (he looks vaguely familiar- he might have been in a “boy band” in the 90s). He asks you what the most likely diagnosis is AND what other tumor would have an identical immunohistochemical staining profile (i.e. be positive synaptophysin and chromogranin)? -The most likely diagnosis is pulmonary carcinoid tumor (typical type). -The other tumor that would be positive for synaptophysin and chromogranin is small cell carcinoma of the lung compared to carcinoid tumors these have many more mitotic figures, areas of necrosis, cells with little cytoplasm and cells that tend to mold against one another Case #1- COPD with fever The patient continues to improve. He has only had limited mobility since entering the hospital as he finds it difficult to get “up and about” with his illness. Two days after his bronchoscopy he complains of suddenly being a bit more short of breath than he was before and he feels as if his heart is racing more than usual. What are two diagnostic considerations? 1) It is possible that he has developed another pneumothorax 2) Pulmonary thromboembolic disease Case #1- COPD with fever Emergent Chest CT is performed which shows evidence of a pulmonary thromboembolism. Being a thorough medical student you ask if he has any family history of thrombembolic disease. He states that some of his brothers and sisters have had blood clots in there legs and one of them died suddenly of unknown cause. Armed with this information, what are the risk factors in this patient? 1) Immobility 2) Hypercoaguable state (likely hereditary) Case #1- COPD with fever A central venous catheter was inserted to monitor this now hemodynamically unstable patient. This shows an elevation of the pressure in the right side of the heart. What two conditions are contributing to the elevated right sided pressure in this patient? 1) Pulmonary thromboembolism 2) Chronic obstructive pulmonary disease (COPD) Case #1- COPD with fever The patient takes a turn for the worst. His blood pressure becomes more unstable and he suffers a myocardial infarction followed by cardiopulmonary arrest. Resuscitation is successful however he was profoundly hypotensive for a prolonged prior of time while resuscitated and he remains hemodynamically unstable with very low blood pressure. His chest x-ray develops progressively more and more infiltrates and now appears“whited-out”. He ends up on mechanical ventilation. If pulmonary function tests could be performed now what would the pattern look like now (also assume that there is no contribution from his prior diagnosis of COPD)? (advance to next slide dont go back and look at prior slide) Case #1- COPD with fever A- this shows an obstructive pattern with decreased FEV1; B shows a restrictive pattern - FEV1 is normal- FVC is significantly decreased (correct answer); C shows a crazy pattern- maybe someone breathing out who is connected to a vacuum cleaner Volume (L) Time (seconds) 1 Volume (L) Time (seconds) 1 V