Bacterial Diseases PDF

1 BACTERIAL DISEASES Syphilis Tuberculosis Leprosy Actinomycosis Cancrum Oris -...

1 BACTERIAL DISEASES Syphilis Tuberculosis Leprosy Actinomycosis Cancrum Oris - NOMA Gonorrhea Syphilis Syphilis is a a highly contagious sexually transmitted disease caused by the spirochete bacteria Treponema pallidum. It is acquired by sexual contact with a partner with active lesions, by transfusion of infected blood, or by transplacental inoculation of the fetus by an infected mother. Humans are the only known natural hosts to this microorganism When the disease is spread through direct contact, a hard ulcer, or chancre, forms at the site of spirochete entry. The ulceration is typically deep with a red, brown, or purple base and an irregular raised border, with resemblance to a chronic traumatic ulcer, squamous cell carcinoma, and non- Hodgkin’s lymphoma. HIV infected patients frequently develop multiple primary lesions. Syphilis can be classified as either congenital or acquired. The acquired form can be classified as primary, secondary, latent, and tertiary, depending on the elapsed time after exposure; primary and secondary are defined as present for one year or less after the initial infection; late syphilis is present for more than one year. Congenital syphilis is transmitted to newborns in uteri, and depending on the time of the manifestation is classified as recent or late.  2 A. Primary syphilis - Chancre Primary syphilis results in painless indurated ulcer(s) with rolled margins at the site of inoculation. The lesion classically presents with a typical painless, self-healing ulcer that develops at the site of inoculation, usually on the genitalia, depending on the site of primary infection, lip, oral, and finger lesions also occur and exhibit similar clinical features. The lesion does not produce an exudate. Regional lymphadenopathy, typified by firm, painless swelling, is also part of the clinical picture. The lesion heals without therapy in 3 to 12 weeks, with little or no scarring. * chancre: indurated/hard ulcer that develops at the site spirochete entry - deep ulcer with a red, brown, or purple base and an irregular raised border - oral lesions in the primary stage are associated with oral sex habits The ulceration of primary syphilis may be confused with other solitary ulcerative disorders, most notably traumatic ulceration, squamous cell carcinoma, and non-Hodgkin's lymphoma. B. Secondary syphilis In untreated syphilis, secondary disease begins after about 2 to 10 weeks; develops as a result of systemic spread beyond the primary infection site - the spirochetes are now disseminated widely. * patients infected via transfusion bypass the primary stage and begin with secondary syphilis Results to formation of a reddish brown maculopapular cutaneous rash and mucosal ulcers covered by a mucoid exudate (mucous patches). Elevated broad-based verrucal plaques, known as condylomata lata, may appear on the skin and mucosal surfaces. Inflammatory lesions may occur in any organ during secondary syphilis.  3 2 principal oral features of secondary syphilis: 1. Mucous Patches - present on the tongue, lips and buccal mucosa; highly contagious - oval-to-crescenteric reddish maculae or maculopapular eruptions erosions or shallow ulcers of about 1 cm diameter, covered by a grey mucoid exudate and with an erythematous border; this is called, syphilitic rosette - mucous patches may coalesce to give rise to, or arise de novo as, serpiginous lesions, sometimes termed snail track ulcers. 2. Maculopapular Lesions - Macular syphilides - macular lesions that arise on the hard palate and manifest as flat-to-slightly raised, firm, red lesions * Grey or white, moist papules or plaques representing oral condyloma lata can also be observed  4 Condylomata lata or condyloma latum, is a cutaneous condition characterized by wart-like lesions on the genitals. They are generally symptoms of the secondary phase of syphilis. Characterized by painless, mucosal, and warty erosions which are flat, velvety, moist and broad base in nature. They tend to develop in warm, moist sites of the genitals and perineum. These lesions hold a high accumulation of spirochetes and are highly infectious. Complete resolution of the lesions is spontaneous and occurs after a few days to many weeks, where it is either resolved completely or enters the tertiary phase, defined by a latent state. Syphilis has important clinical implications for clinicians because manifestations can occur in the mouth and primary and secondary syphilis are highly contagious. C. Latent stage - disease enters long periods of latency that can last from 10 to 30 years D. Tertiary syphilis - arises in about one third of patients with untreated secondary syphilis; there is involvement of the skin, mucosa, cardiovascular and CNS, liver, spleen and other organs Manifestations of tertiary syphilis take many years to appear and can be profound, because there is a predilection for the cardiovascular system and the CNS. Fortunately, this stage of syphilis has become a rarity because of effective antibiotic treatment. In untreated disease, approximately one third of patients progress into a tertiary stage. Focal granulomatous lesions (gummas) may involve any organ. Intraorally, the palate is typically affected, which can lead to palatal perforation. Development of generalized glossitis with mucosal atrophy may also develop. - gumma - tend to arise on the hard palate and tongue; lesions are not infective - firm, nodular mass in the tissue which may form a deep painless ulcer; there may be eventual bone destruction, palatal perforation, and oro-nasal fistula formation.  5 Congenital Syphilis Congenital syphilis is transmitted in the uterus from the infected mother to the fetus after the 16th week of pregnancy. Systemic manifestations of late congenital syphilis are recognized by a classic triad of findings referred to as Hutchinson's triad: (1) interstitial keratitis of the cornea, (2) eighth nerve deafness, and (3) dental abnormalities. Dental abnormalities are probably caused by spirochetal infection of the enamel organ, causing screwdriver-shaped incisor (Hutchinson's incisors) and Mulberry molars. Other intra-oral findings may include atrophic glossitis, palatal cleft, and perioral rhagades (fissures). Tuberculosis An infection of the lungs caused by the organism Mycobacterium tuberculosis, organisms that are resistant to destruction by macrophages and are able to form destructive lesions. Oral manifestations that usually follow implantation of M. tuberculosis from infected sputum may appear on any mucosal surface. The tongue and the palate are favored locations. The typical lesion is an indurated, chronic, nonhealing ulcer that is usually painful, tongue and palate are favored locations Bony involvement of the maxilla and mandible may produce tuberculous osteomyelitis. This most likely follows hematogenous spread of the organism. Pharyngeal involvement results in painful ulcers, which may cause dysphagia, odynophagia, and voice changes. * Primary tuberculosis of the oral cavity is rare – the intact oral mucosa is relatively resistant to invasion of bacilli due to the following reasons: - cleansing action of the saliva; - the presence of salivary enzymes; - tissue antibodies; - oral saprophytes - a plant, fungus, or microorganism that lives on dead or decaying organic matter. - thickness of the protective epithelium * Microorganism needs a disruption of the oral mucosa to become pathogenic  6 Leprosy - Hansen’s disease Leprosy is a chronic infectious disease caused by the acid-fast bacilli Mycobacterium leprae and Mycobacterium lepromatosis. Leprosy is only moderately contagious; transmission of the disease requires frequent direct contact with an infected individual for a long period, with an incubation period ranging up to 5 years – 12 years. Oral lesions appear in the lepromatous form of the disease in 20% to 60% of cases, as multiple nodules (necrotic and ulcerated), with associated slow healing and atrophic scarring. Generally, skin and peripheral nerves are affected because the organism grows best in temperatures less than the core body temperature of 37 degrees. Lesions commonly occur in the palate as progressively growing indurated mass that is fixed to the underlying maxillary bone Involvement of the lips may present as macrocheilia, presence of flat-topped nodules and microstomia; swollen and rigid appearance of the lips may be marked and hence cosmetically quite troublesome. Nodular lesions may be present over the anterior part of the tongue, giving a pavement-stone appearance and ultimately lead to scarring. Involvement of gums may be in the form of gingivitis, periodontitis and periodontoclasia; gums appear swollen with shiny and purplish mucosa and bleed easily with decreased sensitivity to pain. Cutaneous lesions appear as erythematous plaques or nodules, representing a granulomatous response to the organism. Similar lesions may occur intraorally or intranasally. In time, severe maxillofacial deformities may appear, producing the classic destruction of the anterior nasal spine and anterior maxillary alveolus, as well as intranasal inflammation and tissue destruction called facies leprosa.  7 Actinomycosis – Lumpy Jaw Actinomycosis is a chronic bacterial disease that, as the name suggests, exhibits some clinical and microscopic features that are fungus-like. It is most commonly caused by Actinomyces israelii, an anaerobic or microaerophilic, gram-positive bacterium. A. israelii is a normal inhabitant of the oral cavity in a majority of healthy individuals. It is usually found in tonsillar crypts, gingival crevices, carious lesions, and nonvital dental root canals. Actinomycosis is not regarded as a contagious disease because infection cannot be transmitted from one individual to another. Infection usually appears after trauma, surgery, or previous infection. Tooth extraction, gingival surgery, and oral infection predispose to the development of this condition. When it occurs in the head and neck, the condition is usually designated cervicofacial actinomycosis. It typically presents as swelling of the mandible that may simulate a pyogenic infection. Lesions are characterized by a chronic suppurative and granulomatous inflammation that may result in multiple abscesses and sinus tract formation. Typically presents as indurated swelling of the mandible and eventually form one or more draining sinuses from the medullary spaces of the mandible to the skin of the neck. The clinical course ranges from acute to chronic. The skin lesions are indurated and are described as having a “woody hard” consistency. Any mucosal site may be involved; bony sites are also commonly infected. Involvement of the maxilla, results in an osteomyelitis that may drain through the gingiva via a sinus tract. Formation of granulation tissue and abscess in the submandibular region, produce the so-called lumpy jaw.  8 Pus draining from the chronic lesion may contain small yellow granules, known as sulfur granules, which represent aggregates of A. israelii organisms. Spontaneous draining sinus – yellowish fluid causing smell but normal taste. Radiographically, actinomycosis presents as a radiolucency with irregular and ill-defined margins. Noma - Cancrum Oris, Gangrenous Stomatitis Noma is a devastating disease of malnourished children that is characterized by a destructive process of the orofacial tissues. The condition is rare in developed countries but is a relatively common cause of childhood mortality and morbidity in parts of Africa, South America, and Asia. Mortality - the state of being subject to death. Morbidity - the condition of suffering from a disease or medical condition Opportunistic pathogens invade oral tissues resulting to necrosis of tissue in patients whose defenses are weakened by malnutrition, acute necrotizing gingivitis, debilitating conditions, trauma, and other oral mucosal ulcers. Other predisposing factors include debilitation caused by systemic disease, such as pneumonia or sepsis. A severe disfiguring gangrene of the mouth and face that commonly affects children. The initial lesion of noma is a painful ulceration, usually of the gingiva or buccal mucosa, which spreads rapidly and eventually becomes necrotic.  9 It spreads rapidly through the tissues of the mouth and face; the commencement of gangrene is denoted by the appearance of the blackening of the skin. Denudation of involved bone may follow, eventually leading to necrosis and sequestration. Teeth in the affected area may become loose and exfoliate. Penetration of organisms into the cheek, lip, or palate may also occur, resulting in fetid necrotic lesions. The subcutaneous fat pad and the buccal fad pad undergo necrosis in advance to the other adjoining soft tissues; the odor of the gangrene tissues is extremely foul. The overlying skin becomes inflamed, edematous, and finally necrotic, with the result that a line of demarcation develops between healthy and dead tissues, a large masses of the tissue may slough out, leaving the jaw exposed. Therapy involves treating the underlying predisposing condition, as well as the infection itself. Therefore fluids, electrolytes, and general nutrition are restored, along with the introduction of antibiotics. Antibiotics of choice include clindamycin, piperacillin, and the aminoglycoside gentamicin. Debridement of necrotic tissue may be beneficial if destruction is extensive, with reconstructive surgery a late option following acute management and healing. The word noma derives from the Greek "voun", meaning to devour, emphasizing the rapid progression of the disease  10 Gonorrhea - Clap A common human sexually transmitted infection caused by the bacterium Neisseria gonorrhoeae. The infection is transmitted from one person to another through vaginal, oral, or anal sex; it cannot be spread by toilets or bathrooms. It has a short incubation period of less than 7 days; symptoms may be absent especially in females. A mother may transmit gonorrhea to her newborn during childbirth; when affecting the infant's eyes, it is referred to as ophthalmia neonatorum. Pharyngeal gonorrhea- pharyngeal mucosa is more likely to be infected because of the type of epithelium and its reduced resistance to trauma; the chief complaint may be sore throat, although many patients are asymptomatic. Transmission of gonorrhea from an infected patient to dental personnel is highly unlikely because the organism is very sensitive to drying and requires a break in the skin or mucosa to establish an infection. Gloves, protective eyewear and mask provide adequate protection from accidental transmission. Prepared By: DR.F. M. TAN