4. Fungal infections Flashcards
What is the most common oral fungal infection in humans?
Candidiasis
What is the most common Candida?
Candida albicans: yeast like fungal organism
How many forms do C. albicans exist in?
Dimorphic (Yeast form and Hyphal form)
Which C. albicans form invades the host tissue?
Hyphal form
What are common causes of oral candidiasis?
Broad spectrum antibiotics
Immunosuppression
Idiopathic
Clinical patterns of candidiasis?
Pseudomembranous
Erythematous
Chronic hyperplastic
Mucocutaneous
What is pseudomembranous candidiasis aka?
thrush
How does thrush clinically present?
Removable creamy white plaques
What patient population often gets pseduomembranous cadidiasis?
Immunocompromised pts
infants
patients on broad spectrum antibiotics
Symptoms of pseudomembranous candidiasis?
very mild
may have burning sensation and foul taste
Dx of thrush?
cytological smears
Tx of pseudomembranous candidiasis?
identify underlying cause and correct
antifungal antibiotics
no Tx needed for infants
Population that gets erythematous candidiasis?
Much more common
most patients are not immunocompromised
Symptom of erythematous candidiasis
Red mucosa
Common clinical presentations of erythematous candidiasis
denture stomatitis
acute atrophic candidiasis
median rhomboid glossitis
angular cheilitis
What is denture stomatitis?
Varying degrees of erythema localized to the denture wearing area
rarely symptomatic
Causes of denture stomatitis?
Reaction to denture material
Unusual pressure on the mucosa
Presence of candida (mostly on maxilla)
If candida seen on denture in denture stomatitis, what must we be concerned with?
Patient sleeping with denture on.
When is acute atrophic candidiasis often seen?
After broad spectrum antibiotics or suffer from xerostomia
S/S of acute atrophic candidiasis
Diffuse loss of filiform papillae of the dorsal tongue – loss of this keratin tissue leaves tongue very red
Burning tongue sensation
What is median rhomboid glossitis?
Well demarcated erythematous zone along the midline of the posterior dorsal tongue but anterior to terminal sulcus due to loss of filiform papillae
Does median rhomboid glossitis appear smooth or nodular?
Usually smooth but may be nodular
What is the kissing lesion?
It is a palatal lesion caused by contact with the dorsal tongue with median rhomboid glossitis
Tx for median rhomboid glossitis?
Can be treated causing redness/nodules to decrease in size
often after Tx, the condition will recur
uncurable
What is angular cheilitis?
Erythema, fissuring and scaling of the corners of the mouth
Causes of angular chelitis?
- Bacteria infection
- Often co-infection with candidiasis
- Vit B deficiency
- rare except alcoholic population
- Candidiasis
- MCC
- May be co-infectoin with S. aureus
- Occurs in conditions when saliva pool at the corners of the mouth
- often a result of loss of vertical dimension or drooling
Tx of angular cheilitis?
Adress underlying cause
antibiotics
What is cheilocandidiasis?
type of exfoliative cheilitis that is usually periooral
caused by licking or sucking of lips on a regular basis
S/S of chronic hyperplastic candidiasis?
white plaque that is not removable
Background may be red and inflamed
usually asymptomatic
Dx of chornic hyperplastic candidiasis?
Biopsy is usualy necessary bc it clinically resembles pre-malignant lesions
histology of chronic hyperplastic candidiasis?
Candidal hyphae invade the surface epithelium
What is mucocutaneous candidiasis?
A genetic mutation causes patient to develop an immune disorder.
The disorder allows candida to infect multiple mucous membranes causing widespread infection
How does mucocutaneous candidiasis affect our endocrine system?
some mucocutaneous patients develop auto-antibodies against endocrine glands.
Will develop endocrine abnormalities later in life: hypothyroidism, hypoparathyroidism, Addison’s disease, DM, etc
These pts need to be evaluated periodically for endocrine fxn
These endocrine condiitons are called:
endocrine candidiasis syndrme; autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy
Dx of oral candidiasis
Clinical presentation
&
Biopsy or Cytological smear
Tx of oral candidiasis
Antifungal Tx may be necessary
underlying cause needs to be corrected
How do histoplasmosis, coccioidomycosis and cryptococcosis infections differ from candidiasis?
they cause deep fungal infections while Candida infections are superficial
How does an healthy patient deal with histoplasmosis, coccioidomycosis and cryptococcosis infections?
MAcrophages immediately come in and phagocytose the spores causing mild to no symptoms
How does an immunocompromised patient deal with histoplasmosis, coccioidomycosis and cryptococcosis infections?
Their bodies cannot confine the spread of the infection and more macrophages are brought into the area of infection. This results in greater destruction of the lungs .
S/S of histoplasmosis, coccioidomycosis and cryptococcosis infection?
Coughing
Chest pain
Hemoptysis
How do histoplasmosis, coccioidomycosis and cryptococcosis infections spread systemically?
When pulmonary infection reaches bronchus, fungi can implant into sputum. Sputum coughed into mouth then causes oral infection.
Can spread to anywhere in the body by hematogenous spread when cavitation involves blood vessels.
How is histoplasmosis contracted?
Inhalation of spore
What is the most common systemic fungal infection in US?
Histoplasmosis
What is the most common deep fungal infection in HIV pts?
Histoplasmosis
What is the endemic area of histoplasmosis?
Mississipi and Ohio River Valleys
How is Coccidioidomycosis contracted?
Inhalation of spores
What is the endemic area of Coccioidomycosis?
Central valley of CA
how is cryptococcosis contracted?
inhalation of spores
How is cryptococcosis distributed?
World wide distribution in pigeon dropping
how does cryptococcosis affect HIV pts?
Used to be a significant cause of death in HIV pts before HAART
S/S of histoplasmosis, coccioidomycosis and cryptococcosis oral lesions?
Chronic non healing ulcers, Base appears like granulation tissue
Other diagnosis that may present similarly to histoplasmosis, coccioidomycosis and cryptococcosis oral lesion?
squamous cell carcinoma (must biopsy bc of this resemblance)
traumatic ulceration
deep fungal infections
oral TB
primary syphilis
Dx of histoplasmosis, coccioidomycosis and cryptococcosis infection
Serology and cultures are needed to confirm diagnosis
Biopsy required due to resemblance to SCC
Histology of histoplasmosis, coccioidomycosis and cryptococcosis infections?
granulomatous inflammation
special stains are used to demonstrate the fungus
Tx of histoplasmosis, coccioidomycosis and cryptococcosis
antifungal agents
What are the other two terms for zygomycosis?
Mucormycosis
phycomycosis
What causes zygomycosis?
Caused by fungi in the class of zygomycetes
What two populations are affected by zygomycosis?
Uncontrolled DM that develop ketoacidosis
Immunocompromised pts
Dx of zygomycosis
Biopsy/culture because clinical presentation mimics malignancy
histology
Histology of zygomycosis
Extensive tissue necrosis from angiotropic action. fungi invades vessel wall resulting in ischemia, infarction and necrosis
Characteristic fungal hyphae
What is the most important form of zygomycosis for us?
Rhinocerebral form
What is rhinocerebral form zygomycosis?
Fungal infection that usually attacks the midface area resulting in extensive necrosis
What is the primary site affected by rhinocerebral form zygomycosis?
Nose
- Spores are inhaled into nasal cavity and settle in nose
Nasal S/S of rhinocerebral zygomycosis
Nasal obstruction
Epistaxis
Facial pain
Diffuse tissue destruction involving the midface area
Infection spreads to adjacent areas (eyes, brain) leading to visual disturbances and neurologic symptoms
spread causes poor prognosis
how can rhinocerebral zygomycosis extend to the oral cavity?
Spreading to the maxillary sinus
How does the maxillary sinus involvement in rhinocerebral zygomycosis extend to the oral cavity?
Starts as swelling and ulceration of the maxillary alveolar process and palate
If not treated, lesion proceeds to develop palatal necrosis and perforation
Rhinocerebral zygomycosis Tx
Tx based on histology and starts before obtaining culture results
Surgical debridement
systemic antifgunal Tx
management of underlying predisposing conditoin
Time is key!
Rhinocerebral zygomycosis prognosis
poor; 60% death rate
What are two forms of aspergillosis?
Non-invasive
Invasive
What population fo pts develop non invasive aspergillosis?
healthy patients
What population of pts develop invasive aspergillosis?
Immunocompromised
What are the two types of non-invasive aspergillosis?
Mycetoma (aspergilloma)
Allergic fungal sinusitis
S/S of mycetoma
Symptoms similar to sinusitis
Mass of fungal hyphae in sinus
No tissue invasion from mass
Mass can cause dystrophic calcification causing opacity on radiograph
Mycetoma Tx
surgical debridement
What kind of patients develop allergic fungal sinusitis?
Ectopic pts with allergic response to fungus
Biopsy of allergic fungal sinusitis
scattered fungal hyphae
allergic mnucin
eosinophils
Allergic fungal sinusitis Tx
debridement to get rid of fungus and corticosteroids to treat allergy
What are the two forms of invasive aspergillosis?
Local invasive aspergillosis
Disseminated aspergillosis
Characteristics of local ivasive aspergillosis?
Tissue invasion
may spread to adjacent structures (CNS)
prognosis and Tx depends on pts immune status
Disseminated aspergillosis characteristics
Immunocompromised pts
Widespread infection
Tx of disseminated aspergillosis
Surgical debridement
systemic antifungal agent
management of underlying predisposing condition
Disseminated aspergillosis prognosis
Very poor
