Microbiology Flashcards
What type of HSV causes oral lesions?
HSV1
In regards to HSV what is its main method of infection?
Saliva
What is the name given to the primary HSV1 infection?
Primary Gingivostomatitis
Who is mainly affected with primary gingivostomatitis?
Young school children generally pre school.
What is the clinical presentation of someone with gingivostomatitis?
Systemic upset
Fever
Vesicles - lips buccal cavity and hard palate
Ulcers
Generally primary gingivostomatitis requires acyclovir ? T/F?
Generally self resolving , if not then acyclovir is used in severe or unresolved cases.
What happens post primary HSV1 infection?
The virus sits within the sensory nerve cells until reactivated, not all reactivations are symptomatic.
What is a secondary reactivation of HSV1 commonly called?
A cold sore
In regards to cold sores what is the natural history?
A decreasing frequency of reactivations
What is used to detect and diagnose HSV1 latency and infection?
Viral PCR swab
What is the causative organism in herpangina?
Coxsackie virus
Enterovirus
What is the clinal presentation of herpangina?
Vesicles and ulcers on the soft palate
What is used to make a diagnosis of herpangina and Hand Foot and Mouth ?
Viral PCR
What is the clinical presentation of Hand Foot and Mouth?
Ulcers within the mouth.
Blistering ulcers on the foot and hand
High fever
Family outbreak
What is the causative organism in Hand Foot and Mouth?
Coxsackie virus
What is the causative organism in syphilis?
Treponema Pallidum
What is the main clinical sign of a primary syphilis infection?
Chancre- painless ulcer at the site of the ulcer
- Oral or genital usually
Why is it key to diagnose and treat a primary syphilis infection early?
It can progress to secondary and then tertiary syphilis both of which are damaging and ultimately fatal.
What are apthous ulcers?
Non viral and self limiting ulcers
Round or ovoid with an inflammatory halo
If there is a history of recurrent apthous ulcers what should you be worried about?
A underlying systemic disease
List some diseases which are linked to apthous ulcers.
Behcets IBD Reiters Drug reactions Skin diseases
How would behcets present?
Middle East or asian
Recurrent genital or oral ulcers
Uveitis
Visceral organ involvement
How would IBD or gluten intolerance present?
Diarrhoea
Weight loss
Recurrent genital or oral ulcers
How would reiters present?
Arthritis
What skin diseases are linked to apthous ulcers?
Lichen planus
Pemphigus
Pemphigoid
What are the two common causes of pain at the back of the throat?
Acute pharyngitis
Tonsilitis
What are the common causative organisms for acute pharyngitis or Tonsillitis?
Influenza
Strep infection
If the sore throat lasts into the second week what should be suspected?
Glandular fever
List some less common causes of a sore throat?
HIV
Gonococcal pharyngitis
Diptheria
What physical irritants can lead to a sore throat?
GORD
Cigarette smoke
Alcohol
Hay fever
What clinical signs call for immediate hospital admission?
Sore throat with stridor or respiratory difficulty
What is the most common cause of bacterial sore throat?
Strep pyogenes
What is the treatment for acute follicular tonsillitis?
Penicillin
What are you at risk off 3 weeks post acute follicular infection?
Rheumatic fever
Arthritis + Fever + Pericarditis
What are you at risk of 1-3 weeks post acute follicular tonsilitis?
Glomerulonephritis
Haematuria + Albuminuria + Oedema
What is the causative organism in diphtheria?
Coryebacterium Diptheriae
What is the clinical presentation of diphtheria?
Severe sore throat
Grey white pseudomembrane
Low fever
Why is diphtheria a dangerous infection?
The bacteria produces a neurotoxin and a cardiotoxin.
What is the treatment for diphtheria?
Penicillin/Erythromycin
Anti toxin
Supportive therapy
Is diphtheria preventable?
Yes the vaccine is an antitoxin.
What is infectious mononucleosis?
Glandular fever
What is the main causative organism of glandular fever?
Epstein barr virus
What are the main clinical signs of glandular fever?
Fever Enlarged lymph nodes Sore throat Pharyngitis Tonsilitis Malaise Lethargy
What other less common clinical signs might be present in glandular fever?
Jaundice
Rash
Splenomegaly
Leucocytosis
What is the treatment for glandular fever?
Protracted but self limiting illness
Bed rest, Paracetamol, Avoidance of sport
What are some complications of glandular fever?
Splenic rupture
Upper airway obstruction
Increased risk of lymphoma in immunosuppressed
What should be measured in glandular fever?
Epstein Barr virus PCR
IgM
LFT
FBC
What is the causative organism in candida?
Candida albicans
What is the clinical appearance of candida?
White patches on a raw red mucous membrane
What is the cause of candida?
Endogenous loss of flora allowing candida to grow.
Antibiotics, inhaled steroids, immunosuppressed, smokers.
What is the treatment for candida?
Nystatin
Fluconazole
What is the pathophysiology behind most acute otitis media?
Upper respiratory tract infection has spread via the Eustachian tube into the middle ear.
What are the common bacterial causative organisms in acute otitis media?
H.Influenza
Strep.pneumonia
Strep.pyogenes
What is the common history of acute otitis media?
Primary viral with a secondary bacterial infection
How is diagnosis undergone in acute otitis media?
If the tympanic membrane ruptures you are able to take a PCR of the pus
What are the risks associated with malignant otitis?
There is a risk of osteomyelitis and then subsequent meningitis.
How does malignant otitis start?
Normal infection of the ear canal which invades into the temporal bone.
How does someone with malignant otitis present?
Pain and a headache more severe that the clinical picture.
Granulation tissue at the seam between bone and cartilage.
Exposed bone on exploration
Facial nerve palsy
What investigations are undertaken in a suspected malignant otitis?
Plasma Viscosity
MRI
Biopsy
Culture
List some risk factors for developing malignant otitis
Diabetes
Radiotherapy
What is otitis externa?
Inflammation of the outer ear
How does someone with otitis external present?
Erythema and inflammation
Sore and painful ear
Increased discharge and earwax
Loss of hearing
What are the common bacterial causes of otitis externa?
S.aureus
Pseudomonas Aeruginosa
What are the common fungal causes of otitis externa?
Aspergillus niger
Candida Albicans
What is the treatment for mild to moderate cases of otitis externa?
Topical aural toilet
If the patient presents with severe otitis externa what should be done?
Swab sent to microbiology and subsequent prescription
How does sinusitis present with the initial URT virus?
Mild discomfort over frontal and maxillary sinuses
If someone develops a secondary bacterial infection from their viral sinusitis how does the clinical picture change?
Severe pain over the frontal and maxillary sinuses
Purrulent rhinorrhea
When are antibiotics used in sinusitis?
Severe cases which haven’t resolved in 10 days
What is first line in sinusitis?
Phenoxymethylpenecillin
What is 2nd line in sinusitis and when can it not be used?
Doxycycline
Not used in children