PBL 1 Flashcards
What is pneumonia?
an infection in the lungs caused by microbes which leads to inflammation and fluid in the lung tissue
describe the pathophysiology of pneumonia?
microbe enter the alveoli by inhalation which triggers the immune response. WBCs engulf and kill microbe whilst releasing cytokines but are overwhelmed resulting in the production of exudate which fills the alveolar spaces, rendering them airless
what is bronchopneumonia?
when the infection is throughout the lungs, including the bronchioles and alveoli
what is atypical or interstitial pneumonia?
when the infection is only in the interstitium outside the alveoli
what is lobar pneumonia?
when the infection causes complete consolidation of the whole lobe of the lung
what are the stages of lobar pneumonia?
- congestion
- red hepatization
- grey hepatization
- resolution
outline the congestion phase of lobar pneumonia?
it occurs within 24 hours of infection, many bacteria and not many WBC, lungs look red
outline the red hepatization stage of lobar pneumonia?
occurs after 2-3 days and lasts 2-4 days. affected lung becomes more dry, granular and airless. RBC, WBC, cellular debris and bacteria can clog the airways
outline the grey hepatization stage of pneumonia?
occurs on day 4-6 and lasts 4-8 days. lung looks grey or yellow. Fibrin, hemosiderin and red blood cells break down and lead to a more exudate. Macrophages start to form.
outline the resolution stage of pneumonia?
days 8-10
Fluids and breakdown products from cell destruction are reabsorbed. Macrophages are present and help to clear white blood cells and leftover debris. You may cough up this debris. The airways and alveoli return to normal lung function.
what are the symptoms of pneumonia?
dry or productive cough, difficulty breathing, rapid heartbeat, fever, feeling generally unwell, sweating, shivering, loss of appetite, pleuritic chest pain, haemoptysis, headaches, fatigue, nausea, vomiting, wheezing, joint/muscle pain, confusion/disorientation
what does bronchopneumonia look like on xray?
patchy areas of fluid spread throughout the lungs
what does atypical pneumonia look like on xray?
fluid concentrated in the perihilar region
what does lobar pneumonia look like on xray?
fluid localised to a singular lobe or set of lobes
what are some clinical signs of pneumonia that you would find on examination?
dullness to percussion tatctile vocal fremitus bronchial breath sounds late inspiratory crackles bronchophony egophony
what is tatcile vocal fremitus?
more vibrations from a persons back on repeating certain phrases because sound travels better through fluid than air
what do bronchial breath sounds sound like?
loud harsh, hollow breath sounds which high pitch
what are some causes of pneumonia?
viruses, bacteria, aspiring an object, fungus, hospital-acquired
what are the most common pneumonia-causing bacteria?
streptococcus pneumoniae, staphylococcus aureus, streptococcus agalactiae
how can you prevent pneumonia?
covering mouth and nose when coughing or sneezing, throwing away used tissues immediately, washing hands reguarly, healthy lifestyle, being vaccinated if high risk
how can mild pneumonia be treated?
at home with rest, drinking plenty of fluids and antibiotics if suspected bacteria is cause
how can severe pneumonia be treated?
in hopsital with antibiotics, IV< oxygen and maybe even ventilation
how long should it take for a fever caused by pneumonia to cease?
1 week
how long should it take for chest pain and mucus production caused by pneumonia to cease?
4 weeks
how long should it take for breathlessness and coughs caused by pneumonia to cease?
6 weeks
how long should it take for most symptoms caused by pneumonia to cease?
3 months
what are some complications of pneumonia?
pleurisy, lung abscess, sepsis and acute respiratory distress
what type of antibiotic is penicillin?
a beta-lactam
how does penicillin work?
it binds to penicillin binding proteins and causes inhibition of cell wall syntheses
what are some side effects of penicillin?
nausea, vomiting, diarrhea, abdominal pain, stomach upset, skin rash, hives and itching
what are some examples of macrolides?
erythromycin, roxithromycin, clarythromycin
how do macrolides work?
they inhibit bacterial protein synthesis by preventing peptidyltransferase from adding the growing peptide to the next amino acid
what are some side effects of macrolides?
nausea, vomiting, abdominal pain, diarrhea
what should you tell a patient if you prescribe them antibiotics?
the dosage, whether it should be taken with anything e.g. food, make sure they know to finish the course of treatment even if they feel better, make sure they know to see a doctor if they have severe side effects
how can you tell a bacterial infection from a viral one?
bacterial infections last longer than 10-14 days have a higher fever and the symptoms continue to get worse a few days into the illness than better
why has antibiotuc resistance increased?
widespread antibiotic use e.g. using in livestock, inappropraite prescribing, poor hygeine
how can we prevent antibiotic resistance?
prescribing correctly, completing the full prescription, never sharing antibiotics, good hygeine, avoiding close contact with sick people, practicing safer sex, getting vaccinated
outline the mechanism of anti-bacterial resistance?
mutation causes resistance
using antibiotics creates a selection pressure
resistant bacteria survive and reproduce
they pass on resistant allele by horizontal and vertical gene transmission
frequency of resistant allel will increase in the population
