Candidiasis. Fungal and Parasitic Infections. Types of Candidiasis

Transcription

1 Fungal and Parasitic Infections All pictures are intellectual property of the Division of Oral and Maxillofacial Pathology or its Faculty. Duplication or any unauthorized use is prohibited. Candidiasis Candida albicans, Spores and pseudohyphae (dimorphism) 30-50% carry the organism Three factors can determine infection The immune status The environment of the mouth The strain of candida albicans Types of Candidiasis Pseudomembranous White removable plaques of yeasts, epithelial cells and debris Underlying mucosa is erythematous or normal Non-bleeding Cause: Antibiotics, impaired immune system 1

2 Differential Diagnosis 2

3 Types of Candidiasis Erythematous Acute atrophic: patchy denuded areas; bald tongue Central papillary atrophy of tongue (median rhomboid glossitis) and chronic multifocal candidiasis Angular cheilitis (perlèche): sometimes staph. aureus with candida albicans or alone; cheilocandidiasis Denture stomatitis: Not always associated with candida 3

4 Types of Candidiasis Chronic hyperplastic Cannot be removed Candida albicans can cause hyperkeratosis Speckled leukoplakia Presence of epithelial dysplasia 4

5 Types of Candidiasis Mucocutaneous Immunologic dysfunction Sporadic or A.R. Endocrine-candidiasis syndrome Laboratory Tests for Candidiasis Exfoliative cytology & histopathology KOH (10% solution) Single drop on a slide containing smear tissue; epithelial cells are resolved Culture in Sabouraud s agar 5

6 Treatment Nystatin (polyene): Mycostatin; suspension or pastille; direct contact with fungus Amphotericin B (polyene): Fungizone; suspension (not available anymore); intravenous use for severe and life-threatening infections Clotrimazole (imidazole): Mycelex; cannot be absorbed in the GI tract; Ketokonazole (imidazome): Nizoral; can be absorbed; acidic environment needed; rarely causes liver toxicity; drug interactions with erythromycin, cisapride and astemizole (life threating cardiac arrhythmia) Treatment Fluconazole (triazole): Diflucan; once daily, can be absorbed, rare liver toxicity, can interact with several medications and cause side effects Itraconazole (triazole): Sporanox; severe and lifethreatening side effects Iodoquinol: antifungal and antibiotic properties, combination with corticosteroid (Vytone) excellent for angular cheilitis Histoplasmosis Histoplasma capsulatum Yeast and mold; river valleys Ingested by macrophages, T-lymphocytic immunity; flu-like symptoms Acute (self-limiting), chronic (old, COPD, immunosuppressed) and disseminated (AIDS) forms Mouth: Ulceration, plaques or growths, can mimic squamous cell carcinoma Medications: Amphotericin B, itraconazole, ketoconazole 6

7 Blastomycosis Blastomyces dermatitidis Same region as histoplasmosis Primarily lung, can become disseminated Mouth: Ulceration, erythematous areas Histologically can show pseudoepitheliomatous hyperplasia (mimics squamous cell carcinoma) Paracoccidioidomycosis (South American Blastomycosis) 7

8 Cryptococcosis Cryptococcus neoformans Most common life-threatening fungal infection in AIDS Cryptococcal meningitis Disseminated skin involvement (head and neck) Pigeons Mucopolysaccharide wall for protection Asymptomatic or flue-like illness; severe in immunocompromised patients Zygomycosis (mucormycosis, phycomycosis) Saprobic organism Insulin-dependent diabetics with uncontrolled disease or ketoacidosis; immunocompromised patient; rarely in healthy individuals Rhinocerebral involvement Nasal obstruction, cellulitis, cranial involvement, sinus involvement, oral destruction (can mimic malignancy); small blood vessel invasion resulting in infarction In some cases, therapy should start prior to culture results 8

9 Aspergillosis Aspergillus flavus & fumigatus (most frequent) Noninvasive and invasive Invasive: immunocompromised patients and diabetics Allergic fungal sinusitis Aspergilloma and antrolith Fungi occlude vessels Parasitic infections Toxoplasmosis Developing fetus Immunocompromised patients AIDS, transplant & cancer patients Leishmaniasis (kala-azar) AIDS Cutaneous involvement Rarely intraoral lesions 9