Oral Infections - viral and fungal Flashcards
What viral infections are important orally?
Herpes viruses
- Simplex 1 and 2
- Varicella zoster
- Cytomegalovirus
- Epstein Barr
Coxsackie virus
Measles
Human papilloma virus
Herpes simplex bacteria characteristics?
Enveloped DNA virus Highly cytolytic Infects via heparan sulphate 90-100% of individs have antibodies to herpes simplex
What is type 1 herpes simplex associated with?
Skin and oral mucous membranes
What is type 2 herpes simplex associated with?
Genital mucosa
How is herpes simplex transmitted?
By droplet spread or intimate contact
Pathogenesis of herpes simplex 1?
Virus enters trigeminal sensory neurones
Migrates to the ganglion by retrograde axonal flow
Latency - 50% of cases lie dormant
In 30% of cases virus is reactivated
Migrates to peripheral nerve endings
Virus is shed
Reactivation can be caused by UV, stress, illness, immunosuppression
Herpes simplex - primary gingivostomatitis history?
Children, young adults
Incubation period 5 days
Heal within 10-14 days
Many are subclinical and asymptomatic
Herpes simplex - primary gingivostomatitis signs and symptoms?
Malaise and fever Vesicles which ulcerate Secondary infection Erythematous gingivitis Extra-oral lesions Patchy whiteness on ventral of tongue and/or gingiva
How to diagnose herpes simplex - primary gingivostomatitis?
Made on clinical features
Patients have a rising antibody titre to herpes simplex
Pathogenesis:
- Herpes virus replicates in epithelial cells
- Causes epithelial cell destruction and ballooning degeneration of cells
- Results in intra-epithelial vesicles
Herpes labialis features?
“cold sore”
Occurs in 30% of pts
Herpes labialis clinical features?
Prodromal tingling
Vesicles at the muco-cutaneous junction
Ulcerate and crust over
Lasts 7-10 days
Why is herpes labialis diagnosis difficult?
Difficulty differentiating erythema multiforme
Treatment of herpes labialis?
Effective in prodromal stage
Aciclovir cream (zovirax)
Penciclovir
Herpes varicella zoster virus - what number herpes virus is it?
Type 3 herpes virus
Herpes zoster primary infection and secondary lesion?
Primary infection - chicken pox (varicella)
2ndry - shingles (zoster)
What does herpes zoster most commonly affect?
One of the 3 divisions of the trigeminal nucleus
What are the 3 phases of herpes zoster?
Pre-herpetic neuralgia
- Pain in the affected division, may mimic dental pain
Rash
- Unilateral vesicles: (does not cross the midline) opthalmic, maxillary, mandibular
- Ulcers (mucosa) and crusting lesions (skin)
- Lasts 2-3 weeks
Post-herpetic neuralgia
- Burning pain, affects 10-20%
- More common in elderly
Management of herpes zoster?
Aciclovir 800mg 5 x daily for 7 days
- Valaciclovir 1g 3x daily, 7 days
- Famciclovir 250mg 3x daily, 7 days
Analgesics
Referral to opthalmology if eye involved
Post herpetic neuralgia
- Treat pain with neuropathic pain drugs
- Gabapentin, antidepressants
Epstein-Barr virus (SV4) - what can it cause?
= Infectious mononucleosis (glandular fever)
Burkitt’s lymphoma
= non-hodgkin’s lymphoma
Nasopharyngeal carcinoma
Oral hairy leukoplakia
Clinical signs of Epstein Barr virus infection - infectious mononucleous?
Affects tonsils - increased size
Petechiae on soft palate
Cervical lymphadenopathy
Oral hairy leukoplakia features?
Seen in 25% of HIV infected patients
Can occur in non-HIV patients
Corrugated white patches
Bilateral on lateral borders of the tongue
How to diagnose oral hairy leukoplakia?
Demonstration of EBV in tissues
Cytomegalovirus (HV5) pathogenesis?
Inclusion bodies
Dormant in lymphocytes - interfere with MHC1 presentation
When is cytomegalovirus concerning?
In immunocompromised pts
- Large ragged oral mucosal ulcers
- Salivary gland swelling
- Retinitis
New born
- Life threatening
How can cytomegalovirus (HV5) present?
Rarely causes problems in healthy subjects
- Rare appearances are glandular fever like illness (no lymphadenopathy) and salivary gland swelling
Coxsackie A viruses - what types cause the most problems in the oral cavity?
Types 4, 5, 10 and 16
What can coxscakie A virus 4 cause? Clinical features of this?
Herpangina = Looks like herpes and gives the pt a choking sensation - CVA4 causes it - Mild febrile illness - Young adults and children - Vesicles and ulcers on soft palate - Lasts a few days
Herpangina treatment?
Usually no tx
- Analgesic MW e.g. difflam
What can CVA16 cause? Clinical features of this?
Hand foot and mouth syndrome
- Similar to herpangina, mild systemic upset
- Rash/vesicles on palms of hands, soles of feet
- Intra-oral vesicles and ulcers - anywhere in mouth
What type of infection is measles?
Paramyxovirus
Clinical features of measles?
Pt will be systemically unwell Koplik's spots - White papules on buccal and palatal mucosa during prodromal phase Skin rash Long term effects
Human papilloma virus features?
> 40 types of HPV:
- DNA virus - just 9 genes
- Only infects keratinocytes- gets into basal cells via integrins = virus is internalised and can replicate
- High risk oncogenic subtypes (HPV16 and 18) = cervical, oropharynx and anal cancer
Main oral lesions with human papilloma virus?
Squamous cell papilloma/verruca vulgaris
Condyloma accuminatum = genital warts inside the mouth
Focal epithelial hyperplasia (Heck’s disease)
- HPV13
- Common in small native communities and HIV infection
- Tx - excision, imiquimod 5% cream
Dysplasia/SCC
List the fungal infections that can impact the oral cavity
Aspergillosis Blastomycosis Candidosis Coccidioidomycosis Cryptococcosis Histoplasmosis Rhinosporidiosis
What species cause candidosis?
Candida albicans - most common C.tropicalis C.krusei C.glabrata C.dubliniensis
Predisposing factors for candida?
Prostheses: No exfoliation
Low saliva - no flow = reduces soluble defences (Low pH induced by high sugar diet)
Antibiotics: reduced bacterial competition
Immuno-suppression - reduced cellular defence:
- Young/old
- Diabetes
- Corticosteroids, including steroid inhalers
- Malignancy
- HIV
- Immunosuppressive therapy
Pathogenic/virulence factors of candida?
Hyphal transition and growth is needed for virulence and pathogenesis
Hyphae secrete candidalysin = pore forming toxin that kills human cells and initiates a human response
Proteases - produce SAP:
Sap 1-3 = needed for mucosal infection, degrade complement
Sap 4-6 = contribute to systemic infection
= Invade between/through epithelial cells
ALS1 mediates binding to epithelial surface
Classification of candida infections?
Acute forms
- Acute pseudomembraneous candidosis (thrush)
- Acute atrophic candidosis (antibiotic sore mouth)
Chronic form
- Chronic atrophic candidosis (denture stomatitis)
- Chronic hyperplastic candidosis (candidal leukoplakia)
- Chronic mucocutaneous candidosis (various: inherited syndromes)
Candida associated lesions
- Median rhomboid glossitis
- Angular cheilitis
HIV related candidosis
Acute pseudomembranous candidosis?
Creamy thick white plaques
- Thick biofilm of yeast and hyphal forms
Easily rubbed off
Acute atophic candidosis causes?
Prolonged corticosteroid or antibiotic therapy
Bacterial flora altered, allows candida to flourish
How to treat acute atrophic candidosis?
Reduce antibiotic use if possible
Antifungals
Management of acute atrophic candidosis?
Confirm diagnosis
- Swabs or oral rinse with/without microbial culture
Investigate and treat underlying cause
Treat with anti-fungal agents:
- Miconazole oral gel
- Nystatin suspension - gross taste and use for a month
- Amphotericin B (only in hospital pharmacies)
Systemic:
- Fluconazole = interacts with warfarin
- Itraconazole
Denture related candidosis - when/why does it occur? Clinical appearance?
Palate protected from saliva = antimicrobial properties
Poor denture hygiene
Do not remove denture at night
Redness of palate which follows outline of denture
Treatment for denture related candidosis?
Improve denture hygiene
- Leave out at night
- Clean denture and soak in milton (NOT for CoCr dentures - can use something that is chlorhexidine based) or corsodyl
Antifungals
- Nystatin +/- miconazole gel to fitting surface tds
- 2-3 weeks
Median rhomboid glossitis presentation?
Red depapillated (erythematous area) area in the centre of the dorsum of the tongue
Sometimes have matching lesion in the palate
Epithelial proliferation
Candida in epithelium
Not premalignant
Diagnosis usually on clinical grounds
Angular cheilitis predisposing factors?
Often occurs with denture associated candidosis
Crusting/weeping in corners of mouth
Reduced vertical dimension = drooling of saliva
Haematological deficiency
- Iron, B12, folate deficiency
- Crohn’s disease
Pt may have undiagnosed type 2 diabetes
Some cases associated with staph aureus
Tx for angular cheilitis?
Address underlying cause
Miconazole cream or fusidic acid, depending on cause
Chronic hyperplastic candidosis
White or red/white patch, nodular
Whiteness cannot be rubbed off
Classic sites - labial commissures (start of buccal mucosa next to lip) or tongue
Premalignant
- Up to 25% of malignant change
Diagnosed by biopsy
Aetiology of chronic hyperplastic candidosis?
Usual candida risk factors
Smoking
Not clear if candida cause the lesion or invade a pre-existing lesion
Some lesions regress following antifungal therapy
Histology of chronic hyperplastic candidosis?
Candida at right angles to surface
Hyperplastic epithelium
Management of chronic hyperplastic candidosis?
Diagnosis
- Biopsy
- Assess degree of dysplasia and risk of malignant transformation
Tx
- Systemic antifungals (7-14 days fluconazole or amphotericin B)
- Smoking cessation
If no improvement and high risk of malignant transformation then excise
