Upper Respiratory tract infection Flashcards
What are some of the normal flora of the URT?
Streptococcus viridans, commensal Neisseria spp., diphtheroids, anaerobes.
What are some respiratory pathogens that may be carried asymptomatically?
Streptococcus pneumoniae, Moraxella catarrhalis, Haemophilus influenzae, Streptococcus progenies
Neisseria meningitidis
(not respiratory)
What are some examples of transient colonisation post antibiotics?
Coliforms, Pseudomonas, Candida
What are some examples of bacterial pathogens that affect the URT?
Bordetella pertussis Corynebacterium diphtheriae Haemophilus influenzae Moraxella catarrhalis Streptococcus pneumoniae Streptococcus pyogenes (Lancefield Group A β haemolytic strep) Staphylococcus aureus Group F β haemolytic strep (milleri group)
What are some examples of viral pathogens that affect the URT?
Adenovirus Epstein-Barr virus (EBV) Herpes Simplex (HSV) Influenza and parainfluenza viruses Respiratory syncytial virus (RSV) Rhinovirus Enteroviruses Coronaviruses Human Metapneumovirus (hMPV)
How are respiratory diseases spread?
droplet transmission
“Coughs and sneezes spread diseases”
What is the epidemiology of URTIs?
Most often v. young children/teenagers
Winter/viral. Bacterial and viral common in children.
(Also immunosuppressed - Very ill with seemingly less pathogenic viruses in adults e.g. RSV)
Which viral pathogens can cause colds?
mainly Rhinovirus
also: Coronoviruses RSV, Parainfluenza viruses Enteroviruses Adenovirus
What are the symptoms of rhino-sinusitis?
Facial pain, nasal blockage, reduction of smell
What pathogens can cause rhino-sinusitis?
post viral-inflammation
Streptococcus pneumoniae, Haemophilus influenzae, Streptococcus milleri group, anaerobes, fungal
What are the complications of chronic sinusitis?
Osteomyelitis, meningitis, cerebral abscess
What are the causes of tonsillitis?
Viral: RSV, Influenza, Adenovirus, EBV, HSV1
Bacterial: Streptococcus pyogenes, Rarely - Neisseria gonorrhoeae, Corynebacterium diphtheria
(Mycoplasma pneumoniae and Chlamydophila pneumoniae)
What are the signs and symptoms of pharyngitis/tonsilitis?
Symptoms and signs
S/T, dysphagia, fever, headache, red tonsillar/uvular area +/- exudate. Lymphadenopathy
What are the complications of group A streptococcal infection?
acute glomerulonephritis/ rheumatic fever/scarlet fever.
Aim to prevent this rheumatic fever by giving penicillin and prevent suppurative complications too (e.g. otitis media and quinsy (peritonsillar abscess))
What are the features of glandular fever?
Epstein-Barr virus (EBV)
Teenagers and older. Often asymptomatic.
S/T, fever, cervical lymphadenopathy
Complications e.g. splenic rupture
Avoid ampicillin (mac-pap rash, not a true allergy)
Serology – IgM/IgG, Paul Bunnell Test/PCR
What are the features of Diphtheria?
Corynebacterium diphtheriae Malaise, fatigue, fever +/- sore throat Complications Erythromycin/ penicillin/antitoxin Immunisation/travel history/CCDC
What are the features of epiglottitis?
Cellulitis of epiglottis (“cherry red”) – airway obstruction
Child (2-4 yrs), fever, irritable, difficulty speaking (“hot potato”) and swallowing. Leans forward, drools. Stridor, hoarse.
Lateral neck X-ray – enlarged epiglottis
What is the treatment of epiglottitis?
Treatment - maintain airway, cefotaxime
Must send blood cultures. DO NOT swab or examine epiglottis unless already intubated, or can intubate immediately (theatre).
Previously most commonly caused by H. influenzae type B prior to immunisation. Now rarer and variety causes – esp. resp. bacteria and S. aureus
What are the features of acute laryngitis?
Hoarse/husky voice, globus pharyngeus (lump in throat), fever, myalgia, dysphagia
Usually viral and self-limiting, occas. bacterial (the usual suspects) therefore no need therefore for antibiotics. If severe disease consider antibiotics
In hospital – airway patency if stridor
Non infective causes (voice abuse, malignancy etc.)
What are the features of croup/ acute laryngotracheobronchitis?
“… the sharp stridulous voice which I can resemble to nothing more nearly than the crowing of a cock…is the true diagnostic sign of the disease.” Francis Home 1765
Inflammation of larynx and trachea after infection of upper airways
Children
Viral esp. parainfluenza type 2 therefore NO antibiotics (also RSV)
What are the features of whooping cough?
Bordetella pertussis - GN coccobacillus
Common, very contagious, adults too.
Pernasal swab and PCR
Incubation period 1-3 wks
Initially catarrhal phase – runny nose, fever, malaise (like any other URTI!).
Later (up to a week), dry non productive cough. This becomes whooping/paroxysms. (short bursts on exhalation, then inspiratory gasp which is the whoop
How is whooping cough treated?
Treatment – supportive and erythromycin
May be prolonged convalescence - weeks
Complications – otitis media, pneumonia Often secondary infection or aspiration). Convulsions. Subconjunctival haemorrhages etc.
Immunisation very important. Erythromycin to household contacts/CCDC.
What are the features of otitis externa?
Infection of the external auditory canal (EAC) – i.e. like any other skin/soft tissue infection in a way, but it’s a narrow canal!
Pain, itch, swelling and erythema, otorrhoea
Main types - acute OE, chronic OE and malignant OE.
Main organisms – skin types – S. aureus (likely if pustular) and Pseudomonas spp.(esp. after swimming)
How is acute otitis externa treated?
Swab EAC
Treatment - toilet with saline and/or alcohol and acetic acid. Wick insertion. Topical drops (these may contain antibiotics, antifungals and steroids)
Chronic otitis externa features?
Irritation from drainage from perforated tympanic membrane.
Itchy
Treat underlying cause
Avoid aminoglycosides (gentamicin etc.) if perforation.
Resistance may form and sensitisation occurs with prolonged courses
What are the features of malignant otitis externa?
Severe, necrotizing. Spreads from local area more deeply. May invade bone, cartilage and blood vessels. Life threatening – spread to temporal bone, base of skull, meninges and brain. Often Pseudomonas aeruginosa
+++ pain, drainage of pus from canal
Elderly, diabetics, immunosuppressed
Treat 4-6 weeks altogether e.g. with iv ceftazidime then oral ciprofloxacin
What are the features of otitis media?
Middle ear inflammation. Fluid present in the middle ear.
V common children
Fever, pain, impaired hearing. Red bulging tympanic membrane
VIRAL. H influenzae, S. pneumoniae, M. catarrhalis
Swab any pus discharging
How is otitis media treated?
Treatment, if not unwell WATCH and treat symptomatically (decongestant etc) and review early. If unwell give amoxicillin.
What is mastoiditis?
Inflammation of the mastoid air cells after middle ear infection. Pus collects in cells and may proceed to necrosis of bone.
Signs as AOM, but pain/swelling over mastoid too.
Much lower incidence after introduction of antibiotics.
How is mastoiditis investigated and treated?
Need bacteriology samples
Imaging – CT helps to assess extent
Similar Rx to acute OM unless Gram negatives are suspected and then need broader spectrum cover as per organism isolated
LTHT 1st line treatment is co-amoxiclav (amoxicillin-clavulanate)
What are other important infections to look out for?
Vincent’s angina
Deep fascial space infections of head and neck – e.g. Ludwig’s angina, Lemierre’s Syndrome
(you aren’t dentists BUT…. Don’t forget about such things as gingivitis/peridontal infection)
What investigations can be done for suspected URTIs?
Send pus/throat swab/blood cultures Gram stain Culture Sensitivity testing Reference laboratory work (typing, toxin detection) Serology and antibody detection
