TUBERCULOSIS
TB is a systemic, chronic granulomatous infectious disease with variable clinical presentation.
Etiology : Mycobacterium Tuberculosis, Acid-fast bacilli.
Myco.TB is aerobic, non-motile, rod shaped, non-sporing bacilli which is stained by Zeihl-Neelsen stain.

Spreads through droplet / aerosol dispersion, rarely by ingestion of unpasterised infected cow milk.
Oral cavity is a rare location of TB.

Constitutional Factors
Low Income group
Low & unhygienic living conditions
Overcrowding
Malnutrition
Lowered host resistance

Stages

Initial infection is in childhood, spread by droplet.

Forms Ghon’s Focus & Ghon’s Complex.

May be Asymptomatic. It may present with, Fever, lassitude, night sweats, Anorexia, cough sputum, weight loss Erythema nodosum.

Depending upon extent of exposure & resistance of the patient, initial infection may progress to

Symptomatic Primary TB,
Formation of Granulomatous inflammation in the lung & hilar lymph nodes.
Heals by tubercle formation (Calcified lung nodules & hilar Lymphadenopathy)

Progressive Primary TB
Miliary TB
Bronchopneumonic TB
GI TB

Reactivation TB
Reactivation of persistent bacilli in tubercles of previous infection
Characterized by tubercles, caseation necrosis, fibrosis & extension of the lesion.

Oral Manifestations
Occur in long standing pulmonary or severe systemic infection

Bacteria can infect Oral tissues or Lymph nodes (Scrofula)

Tongue is the common site followed by palate, lips, gingiva, buccal mucosa,tooth extraction sockets & jaws.

Majority of these lesions are secondary to the lesions in some other parts of the body

Ulcer
May start with a vesicle or nodule which ulcerates.
It is superficial & painful, slowly increasing in size.
Irregular lesion with ragged undermined edges, induration may be variable,often with a yellowish granular base.
Gingival involvement is rare,
Appear as diffuse, hyperemic or nodular papillary proliferation.

Differential Diagnosis
Syphilitic chancre
Traumatic ulcer
Major Apthous ulcer
Carcinomatous ulcer

Dental Considerations

Poses a risk to dentist due its nature of spread

Use of rubber dams, minimum use of ultrasound scalers & high speed hand pieces

Good ventilation to avoid re-circulation of air.

Dental treatment only if only an emergency.

Treatment
Combination therapy: usually 3–4 drugs to prevent resistance, chosen from the following:
ISONIAZID, RIFAMPIN, ETHAMBUTOL, RIFABUTIN, STREPTOMYCIN, PYRAZINAMIDE
Short term chemotherapy (8 weeks with 3-4 drugs)
Prolonged therapy — 6 mo minimum— indicated for slow growth rate of bacteria, on 2 drugs.
Increasing incidence of Mycobacterium tuberculosis drug resistance
Prevention: BCG vaccination in newborns. Questionable in adults.

ACTINOMYCOSIS

It is a chronic granulomatous suppurative type of disease caused by Anaerobic, Gram + ve, non-acid fast bacteria.

These are transitional forms between bacteria & fungi

Most common are Actinomyces Israeli, A.neslundi, A. viscosus, A. odontolyticus.

Breach in continuity of the oral mucosa either because of trauma or surgery- prerequisite for Actinomyces infection.

Classification
Cervicofacial ACM
Abdominal ACM
Pulmonary ACM
Cutaneous ACM

Cervicofacial ACM
Age & Sex- seen in adult Males
Occur due to trauma, presence of long standing carious tooth,
Can penetrate deep in to the oral mucosa due to dental plaque, calculus or gingival debris
Location- Submandibular region is the most frequent site.
Cheek, masseter & parotid gland may be involved.
Trismus is a feature before forming pus

Signs-
Presence of a firm,multiple, non painful, indurated masses in the submandibular region. (Lumpy Jaw Disease)
Development of Fistulas, discharging yellow colored fluid containing the characteristic Submicroscopic Sulphur granules.
Skin around the fistula may show purplish-reddish hue. Multiple fistulas seen commonly discharging with some areas showing signs of healing.
Disfigurement of face is common in long standing cases

Investigation
FNAC
Yellowish fluid / pus, containing typical Sulphur granules
Ray – Fungus appearance
Round/lobulated colony meshwork of filaments.
Stain with hematoxylin & peripheral club-shaped ends stain with eosin.

Treatment
Medical & surgical line of therapy
Lesion should be surgically debrided and thoroughly curetted.
Antibiotic of choice is Penicillin
Given 3-4 million units IV 4th hourly for 2-4 weeks.
Patients allergic to penicillin Erythromycin is the drug of choice.

DIPTHERIA
Acute contagious illness, caused by gram +ve bacillus, Corynebacterium diptheriae.
Also called Klebs Loeffler bacillus
It is transmitted by droplet infection.
Bacilli settle on the upper RT.
It produces powerful exotoxins which diffuses hematogeneously, involving heart, muscle, kidney, peripheral nerves.
Death may be caused by heart failure & airway obstruction.

Oral Manifestations
Seen in children esp. in winter.
Incubation period – 2days
Starts with listlessness, malaise, headache, fever, with sudden onset of sore throat.
Tonsillar area producing thick, firm, leathery, blue-white pseudomembrane.(Diphtheritic membrane)
Neck – is enlarged (Bull neck), edema of pharynx, with cervical Lymphadenopathy nasal regurgitation & dyspnoea.
Laryngeal involvement produces respiratory obstruction & typical croup.

Complications
Myocarditis
Polyneuritis
Acute interstitial nephritis
TREATMENT
Isolate & treat aggressively
Treated with Diphtheria Antitoxin
Mild – 10,000 to 20,000
Moderate – 20,000 to 40,000
Severe – 50,000 to 100,000 AT.
Antibiotics like penicillin / erythromycin.