Oral Infections PDF

Oral Infections Dr. Dilara Kazan Department of Oral&Maxillofacial Surgery Fungal Infections • Candidiasis • Candida albicans, which is part of the normal oral flora, is responsible for the majority of such diseases. • Predisposing factors may be local or systemic. • Oral mucosal candidiasis is cl...

Oral Infections Dr. Dilara Kazan Department of Oral&Maxillofacial Surgery Fungal Infections • Candidiasis • Candida albicans, which is part of the normal oral flora, is responsible for the majority of such diseases. • Predisposing factors may be local or systemic. • Oral mucosal candidiasis is classified into primary and secondary. • The treatment of choice is the systemic use of -azoles with excellent results. • Candidiasis is the most frequent fungal infection and is caused by C. albicans, a fungus found in 20 to 50% of healthy people and is rarely caused by other strains • Candida tropicalis, • Candida glabrata, • Candida krusei, • Candida parapsilosis, • Candida guilliermondii. Fungal Infections • Candidiasis • In healthy individuals, without any local pre-disposing factor, C. albicans causes no clinical manifestations. Predisposing factors for candidiasis include local ones, such as: xerostomia, poor oral hygiene, chronic mucosal trauma, use of local antibiotics, chronic use of inhalational and topical steroids, radiotherapy to the head area, and systemic ones, such as: iron deficiency anemia, diabetes mellitus, primary immunodeficiency, HIV infection and AIDS, leukemia and other malignancies, neutropenia, use of steroids and immunosuppressive medication, broad-spectrum antibiotics, hypoparathyroidism, cortical adrenal insufficiency, and other endocrine diseases. • The newborns and infants are also particularly susceptible to candidiasis. Usually, candidiasis presents as a localized and superficially spreading infection; however, in immunocompromised and neutropenic patients, it has the potential to spread in a systemic fashion with significant mortality. • Oral mucosal candidiasis presents with a wide spectrum of clinical manifestations. • It is classified into primary, including lesions exclusively in the mouth and the perioral area, and secondary, which includes the oral manifestations of the systemic mucocutaneous fungal infections. • The diagnosis is mainly based on the history and clinical features. Fungal Infections • Primary Candidiasis • Pseudomembranous candidiasis is the most common form of the disease and is usually acute, but chronic involvement may also rarely occur. Clinically, it is characterized by creamy white or whitishyellow, slightly elevated spots or plaques, which usually can be easily detached, leaving a raw underlying reddish or normal surface. • May be localized or generalized and may appear at any oral site, but more frequently on the buccal mucosa, the tongue, and the soft and hard palate. • Subjective complaints include xerostomia, a slight burning sensation, and difficulty in swallowing. The diagnosis is usually based on the clinical features. Fungal Infections • Primary Candidiasis • Erythematous candidiasis is also classified as acute or chronic. It is highly prevalent in HIV-infected individuals (not receiving antiretroviral therapy [ART]), but may rarely be observed in patients receiving broad-spectrum antibi- otics, corticosteroids, or other immunosuppressive agents. Clinically, it presents as erythematous patches that have a predilection for the palate and the dorsal surface of the tongue. The patients may describe a burning sensation. Fungal Infections • Primary Candidiasis • Nodular or plaque-like candidiasis is a rare, chronic form of candidiasis that is characterized by deep infiltration of the oral tissues by fungal hyphae and epithelial hyperplasia. Clinically, it presents as white, firm, and raised plaques occasionally surrounded by erythema. • The lesions may persist for years, do not detach, and are usually located on the tongue and the commissures. It has been suggested that this type of candidiasis predisposes to squamous cell carcinoma and can therefore be classified as a precancerous lesion. Fungal Infections • Primary Candidiasis • Papillary hyperplasia of the palate is a rare chronic form of candidiasis that usually affects people with a higharched palate who do not wear dentures. Clinically, multiple, small, spherical nodules appear on the palate, which are usually red White lesions might also be observed. This lesion should not be confused with denture stomatitis, which appears in people wearing dentures. Fungal Infections • Primary Candidiasis • Lesions contaminated with Candida: The lesions do not have C. albicans as their sole etiologic factor, but are caused by a combination of factors. Angular cheilitis, median rhomboid glossitis, and dentureinduced stomatitis are included in this group. Fungal Infections • Secondary Candidiasis • Chronic mucocutaneous candidiasis: This form of candidiasis is a heterogeneous group of clinical syndromes that are characterized by chronic lesions of the skin, nails, and mucosae. It usually appears in childhood and is often associated with numerous immunologic abnormalities, predominantly cell-mediated immunity and rarely of humoral immunity. This type mostly appears sporadically, but there have been families reported with autosomal recessive pattern of inheritance. • Clinically, the early oral lesions are similar to those seen in pseudomembranous candidiasis, but later white plaques appear that are similar to the lesions of chronic nodular candidiasis. • Cutaneous and nail involvement in varying degrees of severity are associated with the oral lesions Fungal Infections • Secondary Candidiasis • Candida-endocrinopathy syndrome: This is a unique form of chronic mucocutaneous candidiasis that is accompanied by endocrinopathies, such as hypoparathyroidism, hypoadrenalism, hypothyroidism, or even pancreatic and ovarian hypofunction. Oral manifestations usually arise at the age of 4 to 6 years and then deteriorate, whereas the endocrinopathy may be delayed in onset. Conjunctivitis and alopecia of eyebrows can also be observed. Fungal Infections • Candidiasis • Diagnosis of most forms of candidiasis is based on the clinical features. However, occasionally the diagnosis should be confirmed by a smear or culture examination or even histologically. • Pathology • Direct microscopic examination of smears and microbiological culture are of limited diagnostic use. In chronic forms, as the nodular candidiasis, histopathologic examination with periodic acid-Schiff (PAS) stain shows hyphae of Candida within the superficial layer of the epithelium. • Treatment • Identification and possible resolution of local or systemic causative factors are essential for the treatment of candidal infection. Nystatin and miconazole are the drugs of choice for topical use. Topical treatment is usually performed to infants and children. Triazoles (e.g., fluconazole, itraconazole) are useful systemic agents. The dosage and duration of treatment largely depends on the type of candidiasis and the presence of predisposing factors. *Prior to treatment of any type of candidiasis, the oral hygiene levels have to be improved and any local or systemic predisposing factors to be dealt with. Fungal Infections • Candidiasis • Treatment Fungal Infections • Candidiasis Differential diagnosis Leukoplakia Hairy leukoplakia Lichen planus Cinnamon contact stomatitis Chronic biting Leukoedema Oral epitheliolysis Mucous patches of secondary syphilis White sponge nevus Discoid lupus erythematosus Erythroplakia Chemical or thermal burns Fungal Infections • Mucormycosis • • • • • • • • • • • • Anopportunistic,fungalinfectioncausedbythe Zygomycetes group of microorganisms and mainly the strains of Mucor, Rhizopus, and Absidia. Main predisposing factors are primary or secondary immunodeficiency and poorly controlled diabetes mellitus. Five major clinical forms are rhino-orbitocerebral, pulmonary, gastrointestinal, cutaneous, and disseminated. The mouth is commonly involved in the rhino- orbitocerebral type. The prognosis is usually poor. & Rare It usually affects debilitated individuals. The most common predisposing condition is poorly controlled diabetes mellitus with ketoacidosis as well as hematologic malignancies, burns, malnutrition, uremia, liver cirrhosis, HIV disease, organ trans- plantation, cancer chemotherapy, and immunosuppression. The fungus is acquired from the environment through spore inhalation and characteristically erodes arteries, causing thrombosis, ischemia, and finally necrosis of the surrounding tissues. Clinical features The rhino-orbitocerebral form is the most common accounting for 40 to 70% of all cases. Clinically, the disease is characterized by low-grade fever, headache, malaise, sinus pain, bloody nasal discharge, periorbital or perinasal swelling and edema, ptosis of the eyelid, extraocular muscle paresis, vision disturbances, facial nerve palsy and progressive lethargy, and eventually death. Palatal necrotic ulceration are the most characteristic oral lesions. The ulcer is sharply demarcated with a characteristic black necrotic eschar while the bone is exposed. Eventually, the soft and hard tissue de- struction leads to perforation of the palate, tooth loss, and collapse of the nasal septum. The mucosa surrounding the ulcer is usually thickened. Orbital and intracranial invasion is a common complication. Early recognition and diagnosis of the disease are crucial for survival. The clinical diagnosis should be confirmed with histology and culture. Fungal Infections • Mucormycosis • Pathology • Histopathologic examination reveals broad ribbon-like Rhizopus hyphae within the necrotic tissues. Suppuration and necrosis as well as blood vessel invasion by the fungi are com- mon. PAS staining is helpful for the detection of the fungus. • Treatment • Intravenous administration of liposomal amphotericin B and surgical debridement of all the necrotic tissues are the first line of treatment. Posaconazole is currently considered as a secondline drug. Identification and correction of underlying predisposing conditions is also important. Differential diagnosis Nasal NK-T non-Hodgkin’slymphoma Wegener’sgranulomatosis Syphilitic chancre Agranulocytosis Malignancies Aspergillosis Other systemic mycoses that affect the mouth Fungal Infections • Aspergillosis • An opportunistic,fungal infection caused by Aspergillus, especially by the strains Aspergillus fumigatus and Aspergillus flavus. • Predisposing factors are primary and secondary immunodeficiencies, burn, surgical wounds. • Intraorally, atypical ulceration is observed with a characteristic yellow-black surface. • The disease is transmitted by inhalation of spores from the soil, water, organic debris, decaying vegetation, and air-conditioning equipment. • Five types of aspergillosis are recognized: allergic broncho- pulmonary, aspergilloma (fungus balls), invasive, chronic necrotizing pulmonary, and cutaneous. • The most common form is invasive pulmonary aspergillosis, which is characterized by high mortality. • The most frequent predisposing factors include: neutropenia, organ transplantation, hematologic malignancies, AIDS, high-dose steroids, and immunosuppressives. • The fungus extends through the epithelial cells eventually invading the vascular endothelial cells, causing necrosis. Fungal Infections • Aspergillosis • Clinical features • The clinical manifestations of invasive pulmonary aspergillosis are fever, dyspnea, dry cough, retrosternal and pleuritic pain, and tachycardia. Oral lesions present as irregular ulcerations with a tendency to spread with a characteristic yellowish-black surface formed by necrotic tissues. • The lesions are most frequently localized in the palate, gingiva, tongue, and the lips and may be the first clinical signs of the disease. Rarely, the disease begins in the oral cavity following a tooth extraction or endodontic therapy and may spread to the surrounding tissues. Perforation of the nasal septum may be observed. The clinical diagnosis should be confirmed with appropriate laboratory tests. Fungal Infections • Aspergillosis Pathology The histopathologic examination of lesions demonstrates septate hyphae with 45-degree branching, especially with PAS and GMS staining. Computed tomography (CT) scan of the chest and microbiological culture from biopsy material can also be helpful toward diagnosis. Treatment Voriconazole and posaconazole are the drugs of choice. Itraconazole (e.g., 200–400 mg/d for 1–4 months, depending on the type and gravity of the disease) is also the first line of treatment. Alternatively, intravenous amphotericin B can be administered in severe systemic infection. Differential Diagnosis Mucormycosis Nasal NK-T non- Hodgkin’slymphoma Wegener’s granulomatosis Agranulocytosis Leukemia Tuberculosis Malignancies Other systemic mycoses that affect the mouth Fungal Infections • • • • • • Histoplasmosis Histoplasma capsulatum is the cause. Endemic in some areas with particularly warm and humid climates. Transmitted through inhalation of the fungus spores. Oral and cutaneous manifestations most commonly result from disseminated disease. The disease is endemic in the United States, in the Mississippi, Ohio River Valleys, and Canada, where approximately 80 to 90% of the adult population may exhibit positive histoplasmin skin testing. Other areas include countries of the South and Central America, Africa, and Asia, while it is rare in European countries. • Oral lesions occur in approximately 35 to 45% of cases and are clinically characterized by irregular and indurated painful ulceration with a verrucous surface. Rarely, nodules can be observed on the palate, gingiva, tongue, and the lips Fungal Infections • • • • • Blastomycosis The dimorphic fungus Blastomyces dermatitidis is the cause. Endemic in certain areas of North America. The lungs are the first point of entry as the fungus is inhaled. The clinical manifestations can be divided into pulmonary and extrapulmonary. • The mouth is affected in approximately 20 to 25% of the cases. • Clinically, oral blastomycosis presents as solitary or multiple ulcers with a slightly verrucous and irregular surface and thin borders that mimic squamous cell carcinoma. Fungal Infections • • • • • • • Paracoccidioidomycosis The dimorphic fungus Paracoccidioides brasiliensis is the cause. Endemic in Central and South America. Transmitted by spore inhalation The lungs, skin, mucosae, gastrointestinal tract, adrenals, spleen, and the lymph nodes are most frequently affected. Oral lesions are common. Clinically, paracoccidioidomycosis is characterized by weight loss, fever, dyspnea, cough, lymph node enlargement, skin rash and ulcers of the nose, larynx, oropharynx, and oral cavity. Clinically, oral lesions usually present as a painful irregular ulcer with a granulomatous surface. • If untreated, perforation of the hard palate may occur in severe cases. A rare clinical presentation is that of primary mucocutaneous form with oral and perioral distribution due to trauma from chewing contaminated sticks and leaves. Fungal Infections • • • • • • Cryptococcosis An opportunistic infection caused by Cryptococcus neoformans. Predisposing factors are primary and secondary immunodeficiencies The disease is classified into pulmonary and disseminated. The mouth is rarely affected, mainly in disseminated disease. It is usually transmitted through airborne fungal spores, usually from dead leaves, stored grain, bird droppings (e.g., pigeons), and compost piles. • The disseminated form usually involves the central nervous system (CNS) followed by bone, skin, genitourinary tract, lymph nodes, liver, spleen, adrenals, and, rarely, the oral mucosa. Cutaneous lesions occur in approximately 15% of patients as papules and nodules that proceed to ulcerate • The oral mucosa is rarely affected with chronic ulceration that can be indurated and tender on palpation • The tongue, palate, gingiva, and tooth socket after extraction are the most common sites of involvement.