Lecture 12 Oct 27th-respiratory

1DDX: LECTURE 12 – OCTOBER 27TH, 2006 CONDITIONS OF THE RESPIRATORY SYSTEM LUNG ABSCESS: • Easy to diagnose • Indication of consolidation. • Can be open or closed. • As it grows, it pushes on other structures. • Immune response/fever • Consolidation (pus-filled). Percussion will be dull, sounds diminished, consolidation tests will be positive. • If abscess opens, patient will expectorate pus. • Patient will sleep on side of abscess. • Cough reflex decreased with alcoholism. • Neurological disease (cough reflex decreased) • General anesthesia (not coughing) On chest x-ray: Lungs look different. Will be light-coloured due to the density caused by white pus in lungs. Typically, rupture of abscess is what brings patient to office. • Complaints such as “can’t sleep on right side”, “coughing all night” • Easier for immune system to deal with it once it ruptures. • Will see fever without source. BACTERIAL PNEUMONIA • Inflammation of alveoli • Serious condition: can be lethal. • Everything up to pneumonia, not really lethal. • •

Transudate and exudates: classification as to how far gone the condition is. Vitality plays a role in prognosis.

• •

Important for us to know pneumonia well! A lot of fatigue is caused by pneumonia.

Ages and types of pneumonia: • 1-5 years: Viral • 5-45 years: Walking • >45 years: Bacterial Signs and symptoms: • Tachycardia: ventilation ratio is low, so body compensates by increasing breathing rate and heart functionally compensates. • See fever and tachycardia? May be lung infection. •

Basolateral crackles (crackles at base of lung) DDX LECTURE 12, OCTOBER 27TH – PAGE 1

•

Pleuritic pain.

•

Pneumonia very serious in children, elderly, immunocompromised.

• •

Crackles: popping sound, noise of alveoli opening. Friction rub: sound of pleura rubbing against each other

Know bacterial pneumonia, and how others differ. ATYPICAL PNEUMONIA • Keeps getting worse with treatment. • With coughers, not a bad practice to put on a mask. Mask them if they are waiting in your clinic for a while (waiting room, around other patients) • Contagious! • CBC an be normal • Worsening cough and fatigue? Think of Atypical pneumonia • Gram stain negative (-) VIRAL PNEUMONIA • Many different causes, including West Nile Virus. • Immune compromise is an important factor • Important to always do vitals! This is how signs and symptoms will be found for this condition. • *Non-purulent sputum. • • •

Rash: think of a virus when you see a rash (in this case, viral pneumonia) Chronic cough with worsening symptoms. Rusty coloured sputum! Hemoptysis.

Example of test question: What conditions will present with hemoptysis? Signs and Symptoms: • Dry, non-productive cough. Dypsnea initially on exertion, but progresses to continuous dyspnea. • Shares some s/sx with AIDS, bacterial pneumonia. AIDS PNEUMONIA • Doesn’t happen if patient is not immunocompromised. • May be useful in diagnosing HIV, could lead to testing for HIV: patient may otherwise be unaware that they are positive for HIV. • PCP exists in all of us, but doesn’t affect us unless we are immunocompromised. • Looks like regular pneumonia on x-ray: has to be diagnosed by specialist. • If T-helper cell count is <200, patient has AIDS, not HIV. • X-ray: lung looks like it is filled with popcorn. • CT scan: see diffuse foci. Patient has no immune system. Whole lung is involved. • Recovery is unlikely without treatment: especially as this targets immunocompromised individuals. DDX LECTURE 12, OCTOBER 27TH – PAGE 2

FUNGAL PNEUMONIA • Pleuritic pain: patient feels “stabbed” with every breath. • Could feel this in front or back. • Doesn’t trigger the immune system in the same way that a bacteria or virus does • Will show up in blood test. • History will tell you which fungus it is. Patient is spelunking in bat caves? Specific fungus will be involved. • IgG titre is elevated • Need prolonged exposure to contract illness from fungus. ASPERGILLOSIS • Fungus in compost and insulation • Ball-forming fungus: will look like this on x-ray. BLASTOMYCOSIS • Close contact with beaver and dog droppings • S/E USA, Mississippi valley, Africa COCCIDIOIDOMYCOSIS • Look for this on NPLEX • Travel to areas listed: risk factor CRYPTOCOCCOSIS Superinfection: happens on top of another infection. ASPIRATION • Patient breathes something into respiratory tract (eg. vomit, water, foreign matter) • Risk with neurological dysphagia • Pink, frothy sputum: can also suggest heart pathology • A nickel, if aspired, will start an immune response, lead to pneumonia • Possible to aspirate bacterial from periodontal disease • Probably starts in 1 lobe (lower lobe), but can spread to both LEGIONNAIRES’ DISEASE • Subtype of bacterial pneumonia • Signs and symptoms of pneumonia • Mental status changes: consider this in any infection in elderly where mental changes are seen • Presents with diarrhea • HISTORY will make you suspect Legionnella pneumophilia • (X-ray that we were shown had electrodes visible on thorax: patient was hospitalized) ACUTE RESPIRATORY DISTRESS SYNDROME (ARDS) = SARS • PEEP=mechanical ventilation with intubation, under pressure, opens lung. Pressure maintained on expiration to force O2 into blood.

DDX LECTURE 12, OCTOBER 27TH – PAGE 3