Fungal and Protozoal Diseases

1
Fungal and Protozoal Diseases
2
Candidiasis

• 30-50 of people may carry the organism with no
  evidence of infection
• Clinical evidence of infection depends on three
  factors
• 1) immune status of host
• 2) oral mucosa environment
• 3) strain of Candida albicans
• Oral candidiasis may develop in people who are
  otherwise healthy

3
Candidiasis

• Pseudomembranous Candidiasis (thrush)
• Adherent white plaques (resembling cottage
  cheese) on tongue, palate, buccal mucosa
• Plaques can be removed by scraping
• Burning sensation, bad taste
• May be initiated by exposure to broad spectrum
  antibiotics (rapid development)
• Longstanding form result of immunosuppression
  (leukemia, HIV infection)

4
Pseudomembranous Candidiasis
5
Erythematous Candidiasis

• Several presentations
• Acute atrophic candidiasis (antibiotic sore
  mouth)
• Central papillary atrophy (median rhomboid
  glossitis)
• Chronic multifocal candidiasis
• Angular cheilitis (involvement of angles of
  mouth)
• Denture stomatitis (erythema localized to
  denture-bearing areas removable dental prosthesis)

6
Erythematous Candidiasis
7
Chronic Hyperplastic Candidiasis

• Candidal leukoplakia
• White patch cannot be removed by scraping
• Mucocutaneous candidiasis
• Severe oral candidiasis as component of
  immunologic disorder

8
Chronic Hyperplastic Candidiasis
9

Candidiasis
Angular cheilitis
?
Mixed infection candida/herpes
Central papillary atrophy of the tongue
Candidal cheilitis
10
Histoplasmosis

• Most common systemic fungal infection in U.S.
• Most individuals who become exposed have no
  symptoms, or only a mild, flu-like illness for
  1-2 weeks
• Acute histoplasmosis is a self-limiting pulmonary
  infection that develops in 1 of people exposed.
  Fever, headache, myalgia, nonproductive cough,
  anorexia

11
Histoplasmosis

• Chronic histoplasmosis usually affects elderly,
  emphysematous white males or immunosuppressed
  patients. Clinically similar to tuberculosis.
• Disseminated histoplasmosis results from the
  progressive spread of infection to extrapulmonary
  sites. Usually occurs in elderly, debilitated,
  or immunosuppressed patients. Very serious,
  results in death of 90 untreated patients.

12
Histoplasmosis

• Most oral lesions of histoplasmosis occur with
  the disseminated form of the disease.
• Solitary, painful ulceration of tongue, palate,
  or buccal mucosa.
• Lesion has firm, rolled margins, may be
  clinically indistinguishable from malignancy.

13
Histoplasmosis
14
Oral Histoplasmosis
15
Blastomycosis

• Acquired by inhalation of spores which grow as
  yeast in alveoli of lungs. Infection is halted
  in lungs in most patients.
• Acute blastomycosis resembles pneumonia most
  patients do not require treatment
• Chronic blastomycosis is more common than acute
  form resembles tuberculosis
• Cutaneous lesions begin as erythematous nodules
  that enlarge and ulcerate

16
Blastomycosis
17
Paracoccidioidomycosis(South American
Blastomycosis)

• Deep fungal infection seen mostly in South
  America
• Pulmonary infection, sometimes spreads to other
  tissues
• Mulberry-like ulcerations most commonly affect
  the alveolar mucosa, gingiva, palate, lip, and
  buccal mucosa, often more than one oral site

18
Paracoccidioidomycosis(South American
Blastomycosis)

19
Coccidioidomycosis(San Joaquin Valley Fever
Valley Fever)

• Usually asymptomatic or mild flu-like symptoms
• Occasionally, hypersensitivity reaction causes
  development of erythema multiforme or erythema
  nodosum
• Chronic progressive pulmonary coccidioidomycosis
  is rare and resembles tuberculosis

20
Coccidioidomycosis (San Joaquin Valley Fever
Valley Fever)

• Disseminated coccidioidomycosis
• Organism spreads to extrapulmonary sites.
• Immunosuppression increases risk of
  dissemination.
• Cutaneous lesions often develop in area of
  central face, especially nasolabial fold

21
Coccidioidomycosis (San Joaquin Valley Fever
Valley Fever)
22
Cryptococcosis

• 5-8 AIDS patients acquire this infection
• Most common life-threatening fungal infection in
  AIDS patients
• Most patients have significant underlying medical
  problem related to immune suppression
• Dissemination common (meninges, skin, bone,
  prostate)

23
Cryptococcosis

• Cryptococcal meningitis characterized by
  headache, fever, vomiting, stiff neck
• Cutaneous lesions (often involving head and neck)
  develop in 10-20 of patients with
  disseminateddisease.
• Erythematous papules or pustules that may
  ulcerate.
• Treatment may be difficult due to underlying
  medical problem

24
Zygomycosis(Mucormycosis Phycomycosis)

• Found in insulin-dependent diabetics with poor
  control also immunosuppressed patients
• Rhinocerebral zygomycosis
• Nasal obstruction, bloody discharge, headache,
  swelling, cellulitis, facial paralysis.
• Maxillary sinus involvement may present as
  intraoral swelling of maxillary alveolar process
  or palate
• Palatal ulceration may evolve with significant
  tissue destruction
• Sinus may appear opaque on radiographs

25
Zygomycosis(Mucormycosis Phycomycosis)
26
Zygomycosis(Mucormycosis Phycomycosis)
27
Aspergillosis

• May present as allergy, localized infection of
  damaged tissue, or invasive infection in
  immunocompromised patient
• May develop following tooth extraction or
  endodontic treatment
• Localized pain, nasal discharge, may lead to
  necrotic palatal perforation in immunocompromised
  patient)
• Disseminated aspergillus occurs primarily in
  immunosuppressed patients

28
Aspergillosis
29
Toxoplasmosis

• Organism found in cat feces (pregnant women
  should avoid situations that place them at risk -
  e.g., changing the litter box)
• In immunocompetent person, infection symptomatic
  or mild, typically no treatment required
• May be devastating for immunocompromised patient
  or developing fetus

30
Toxoplasmosis

• In immunosuppressed patient, may represent new
  infection or reactivation of previously encysted
  organisms.
• Principal groups at risk are AIDS patients,
  transplant recipients, and cancer patients
• Infection can cause necrotizing encephalitis,
  pneumonia, and myositis or myocarditis, CNS
  involvement

31
Toxoplasmosis

• Congenital toxoplasmosis
• Non-immune mother contracts disease during
  pregnancy
• Organism crosses placental barrier and infects
  developing fetus
• Most healthy adults require no treatment
• Treatment often prevents transmission to the fetus