Microbiology 1 - Resp. infections Flashcards
What infections tend to affect the upper respiratory tract?
Common cold (coryza)PharyngitisSinusitisEpiglottitis
What infections tend to affect the lower respiratory tract? (4)
Acute bronchitisAcute exacerbation of chronic bronchitisPneumoniaInfluenza
What is coryza?
The common cold - acute viral infection of nasal passages
How is the common cold spread/
Droplets and fomites
Complications of the common cold? (2)
SinusitisAcute bronchitis
What 3 organisms tend to cause your common cold?
AdenovirusRhinovirusRespiratory syncytial virus
Treatment of acute sinusitis?
Most are viral and therefore self limiting resolving in about 10 days but some need antibiotics
What is a quinsy?
Abscess between tonsil and wall of throat (complication of tonsillitis)
What is diphtheria?
Diphtheria is a potentially fatal contagious bacterial infection that mainly affects the nose and throat, and sometimes the skin -causes a pseudo-membrane to form over the thought and is life threatening due to toxin production - not seen in Uk due to vaccination
What is epiglottitis?
A life threatening inflammation of the epiglottis that can cause obstruction
What is acute bronchitis?
also known as a chest cold, is short-term inflammation of the bronchi (large and medium-sized airways) of the lungs
Clinical features of acute bronchitis?
Preceded by a common coldProductive coughFever in the minority of casesNormal chest examinationNormal chest x-rayMay have a transient wheeze
Treatment of acute bronchitis?
Self limiting in normal meaning antibiotics are not requiredCan lead to significant morbidity in patients with chronic lung disease
Incubation period for rhinovirus?
1-5 days
Incubation time for group A streptococci?
1-5 days
Incubation time for influenza and parainfluenza viruses?
1-4 days
Incubation time for RSV?
7 days
Incubation time for pertussis?
7 -21 days
What is pertussis?
Whooping cough
Incubation time for diphtheria?
1-10 days
Incubation time for EBV?
4-6 weeks
Types of pathogens that tend to cause URTI?
RhinovirusAdenovirysGroup A strepInfluenza and parainfluenzaRSVPertussisDiptheriaEBV
Clinical features of an acute exacerbation of COPD?
Usually preceded by an upper respiratory tract infectionIncreased sputum productionIncreased sputum purulenceMore wheezyBreathlessOn examination:Respriatory distressWheezeCoarse cracklesMay be cyanosedIn advance disease - ankle oedema
What are acute exacerbations of COPD?
a sustained worsening of the patient’s symptoms from his or her usual stable state, which is beyond normal day-to-day variations and is acute in onset
Management of acute exacerbation of COPD?
Manage in primary care with antibiotics (amoxicillin or doxycline), bronchodilator inhalers, short course of steroids in some casesRefer to hospital if evidence of respiratory failure, not coping at homeManagement in hospital = same as before + measure arterial blood gases, CXR to look for other disease, oxygen if respiratory failure
What is pneumonia?
acute inflammation with an intense infiltration of neutrophils in and around the alveoli and the terminal bronchioles.
What is the difference between pneumonia and pneumonitis?
Pneumonia is inflammation of the lung tissue due to infection where as pneumonitis is inflammation of the lungs general (usually used to describe non-infectious causes)
What is it called when the lungs become engorged with blood cells (usually due to pneumonia) and resemble liver tissue?
Red hepatisation
What is pleurisy?
inflammation of the pleurae, which impairs their lubricating function and causes pain when breathing. It is caused by pneumonia and other diseases of the chest or abdomen.
What are the symptoms of pneumonia?
General symptoms e.g. sweats, rigors, malaise, myalgiaCoughConfusionPleurisyHaemoptysisDyspnoeaPreceding URTIAbdo painDiarrhoea
Signs of pneumonia?
FeversRigorsHerpes labialis (cold sores due to reactivation of herpes simplex virus due to alteration in the immune system)TachypnoeaCracklesRubCyanosisHypotension
Do the lips show central or peripheral cyanosis?
Central
Investigations for pneumonia? (7)
Blood cultureSerologyArterial gasesFBCUreaLiver functionChest x-ray
What scoring system is used to determine the severity of CAP?
CURB65
What each part of the CURB65 stand for?
C = new onset confusionU = urea greater than 7R = respiratory rate greater than 30/minB = blood pressure systolic less than 90 or diastolic less than 61 65 = age 65 years or older
How much greater is the mortality for a patient with COPD compared to a patient without with CAP?
10% increased mortality
Apart from CURB65, what are the other severity marker of pneumonia? (4)
Temperature less than 35 or greater than 40Cyanosis PaO2 less than 8kPaWBC less than 4 or greater than 30Muti-lobar involvement
What are the pathogens which cause CAP?
Commonest cause = streptococcus pneumoniae (pneumococcal)Haemophillus pneumoniae and mycoplasma pneumoniae are the next most common causesStaph. aureus, moraxella catarrhalis, legionella sp, and chlamydia account for most of the restGram negative bacilli, coxiella burnetti and anaerobes are rarerViruses account for up to 15%
What is a cause of pneumonia in patients with parrots?
Chlamydia psitacci
Treatment of CAP? (5)
Antibiotics (amoxicillin if mild/ moderate, co-amoxiclav and clarithromycin if severe)OxygenFluidsBed restNo smoking
Complications of pneumonia?
Respiratory failurePleural effusionEmpyema (gets drained)Death
How is pneumonia prevented?
Influenza and pneumococcal vaccines for over 65s, chronic chest or cardiac disease, diabetes, immunocompromisedInfluenza vaccine for health care workers
