glands to manifest hyposalivation in the disease. Histopathology shows clustering of lymphocytic infiltrates and epimyoepithelial islands. Mycobacterial infection The most common head and neck manifestation of tuberculosis mycobacterial disease is infection of cervical lymph nodes. The infection is thought to originate in the tonsils or gingiva, ascending to the parotid gland. Two clinical forms; acute and chronic lesions. Acute lesions have diffuse glandular edema, easily confused with acute sialdentitis or abscess. The chronic lesions occur as slow growing masses mimicking tumors. Examination of the salivary gland History and examination A patient with parotid swelling may complain of swelling, pain, xerostomia, bad taste and sometimes sialorrhoea. The most common presenting symptom of neoplasms (both benign and malignant) is an asymptomatic swelling. Pain is more common in patients with parotid cancer (10–29% feel pain) than those with benign neoplasms (only 2.5–4%), but pain itself it not diagnostic of malignancy. Episodic swelling of major salivary glands accompanied by pain and related to salivary stimuli suggests duct obstruction. Also need to assess the facial nerve. The facial nerve passes through the parotid so may be affected if there is a change in the parotid gland. Facial nerve paralysis in a previously untreated patient usually indicates that a tumour is malignant. Physical examination The superficial location of the salivary glands allows palpation and visual inspection. The inspection must be systematic, both intraorally and extraorally, so no area is missed. For extraoral examination the patients head should be inclined forwards in order to maximally expose the parotid and submandibular glands. A normal parotid gland is barely palpable and a normal sublingual gland is not palpable. Intra-oral examination should include observations for asymmetry, discolouration, pulsation and obstructions in the duct orifices. Swelling of the deep lobe of the parotid gland may be seen intra-orally, and may also displace the tonsil. The minor salivary glands should be examined. The labial, buccal and posterior palatal mucosa should be dried with an air blower or tissue and pressed to assess the flow of saliva. Salivary testing Salivary stimulation This can be done by palpating the parotid gland, thus stimulating it. Assess to see whether there is saliva flowing from the parotid papilla. Sialography Sialograms can identify changes in salivary gland architecture and are useful in the evaluation of major gland swellings It involves the instillation of a radio-opaque fluid into the major gland ductal system. This outlines the major and