Degenerative conditions (Table 42.6)

Sjogren’s syndrome

Sjogren’s syndrome is an autoimmune condition causing pro­gressive destruction of the salivary and lachrymal glands. In 1933 Sjogren first described the association of keratoconjunctivitis sicca (dry eyes) and Xerostomia (dry mouth). Shortly thereafter he noted that these symptoms frequently occurred in patients with rheumatoid arthritis (RA). It has since been realised that Sjogren’s syndrome can occur in association with any connective tissue disorder. Indeed the association is very much commoner in many connective tissue disorders than it is with rheumatoid arthritis. Only 15 per cent of patients with RA develop Sjogren’s syndrome whereas 30 per cent of patients with systemic lupus erythematosus and nearly all patients with primary biliary cirrhosis do so. This combination of dry eyes, dry mouth and a connective tissue disorder — most often RA as this is by far the most frequent connective tissue disorder — is called secondary Sjogren’s syndrome. The same combination of dry eyes and dry mouth but without association with a connective tissue disorder is known as Primary Sjogren’s syndrome. Primary Sjogren’s syndrome also differs from secondary Sjogren’s syndrome by virtue of more severe xerostomia and xerophthalmia, more widespread dysfunction of other exocrine glands, a higher incidence of developing lymphoma and a different antibody profile.

Females are affected more often than males in the ratio of 10:1. Typically they are middle aged. The presenting complaint is usually of the underlying connective tissue disorder and only later does the patient become aware of a gritty feeling in the eyes due to dry eyes or of dry mouth. Occa­sionally there is enlargement of the parotid glands bilaterally and even more rarely the enlarged parotids are painful (Fig. 42.13). Superinfection of the mouth with Candida albicans is frequent. Less frequently the patient develops bacterial sialadenitis due to ascending infection from the mouth. The condition does not invariably progress to total xerostomia and for any individual patient it is nor possible to predict the outcome. The characteristic features of the condition are progressive lymphocytic infiltration, acinar destruction and proliferation of duct epithelium of all salivary and lachrymal tissue.

The diagnosis is often based on the characteristic history. No laboratory investigation is pathognomonic of either primary or secondary Sjogren’s syndrome. However, the following investigations are usually undertaken:

1.       Sialography reveals the progressive damage from punctate sialectasis to total parenchymal destruction leaving no more than a grossly dilated duct (Fig. 42.14).

2. Labial salivary gland biopsy can be misleading particularly if only one minor gland is harvested. The characteristic lymphocytic infiltration is focal and a single gland may not show the changes. A minimum of three glands should be submitted to the pathologist.

3. Estimation of salivary flow may be unhelpful as the nor­mal variation in flow rates makes the interpretation of the results difficult.

4.   Viral staining of the cornea with rose Bengal and examination of the cornea with a slit-lamp is a very sensitive assessment of a dry eye.

5.   Autoantibody screen. See Table 42.7.

6. Blood tests usually show a moderately raised erythrocyte sedimentation rate (ESR) and a mild microcytic anaemia (the anaemia of chronic disease).

The management of Sjogren’s syndrome must be sympto­matic. No known treatment modifies or reverses the xerostomia and keratoconjunctivitis sicca. Artificial tears are essential to protect the cornea. For the dry mouth various artificial saliva preparations are available but often the patient prefers to use frequent drinks and learns to carry a bottle of water with them at all times. If patients are to use saliva substitutes it is important that, if they are dentate, the product should not have a low pH and should contain fluoride as rampant dental caries are a frequent complication. There is also increased incidence of developing lymphoma in patients with Sjogren’s syndrome. The risk is highest in those with primary Sjogren’s syndrome. Monocytoid B-cell lym­phoma is the usual complication. Its onset is often heralded by immunological changes (falling immunoglobulin levels, falling titre of rheumatoid factor, rising B2-microglobulin titre, rising serum macroglobulin titre and the appearance of monoclonal light chains in the serum and urine), lymphadenopathy and weight loss.

 

‘Benign’ lymphoepithelial lesion

The term ‘benign lymphoepithelial lesion’ was coined by Godwin in 1952. Use of the word ‘benign’ to describe the lesion is misleading as approximately 20 per cent of patients with benign lymhoepithelial lesion or Sjogren’s syndrome ultimately develop lymphorna. Histologically it is not possible to distinguish benign epithelial lesions from Sjogren's syndrome. Both are characterised by lymphocytic infiltration, acinar atrophy and ductal epithelial proliferation. Indeed they may well be manifestations of the same condition.

Clinically benign lymphoepithelial lesion presents as diffuse swelling of the parotid. The swelling is firm and often painful. In 20 per cent of cases the parotid swelling is bilateral. Eighty per cent of patients are female and most are over 50 years old at presentation. Often there is an associated connective tissue disorder and the risk of developing lymphoma is particularly high in those with rheumatoid arthritis. Most patients will be treated by parotidectomy in order to establish the diagnosis but if any parotid remnants are left, the swelling may recur again with the risk of lymphomatous change. Prolonged follow-up is essential.

Mikulicz’ syndrome

In 1888 Mikulicz described benign, asymptomatic, symmet­rical enlargement of the lacrimal and salivary glands. His original publication described a series of patients who clearly had a variety of different conditions. Benign lymphoepithelial lesion, Sjogren’s syndrome, lymphoma, lymphocytic leukemia, sarcoid and Sialosis can all present in this way. The term Mikulicz’ syndrome is nor helpful and should nor be used (Fig. 42.15).

Xerostomia

A complaint of dry mouth is common. It seems to be partic­ularly frequent in postmenopausal women who also com­plain of a burning tongue or mouth. Normal salivary flow decreases with age in both men and women. The situation is further confused as patients with Sjogren’s syndrome are frequently unaware of having a dry mouth and patients who complain of dry mouth frequently have normal salivary flow rates. The most common causes of xerostomia in order of frequency are:

  chronic anxiety states and depression;

  dehydration;

  drugs — many drugs have been implicated in causing xerostomia as an undesirable side effect (Table 42.8);

  salivary gland diseases as described earlier.

Xerostomia can be difficult to treat. Treatment is aimed at the relief of symptoms and the avoidance or control of com­plications. Frequent sips of water help most patients. Artificial salvias are nor well accepted but their lubricant properties may be particularly useful at meal times. Cholinergic drugs such as pilocarpine can be tried but their side effects — diarrhoea and pupillary dilatation  often outweigh any benefit.

Rampant caries and destructive periodontal disease are major complications due to oral infection. Meticulous oral hygiene and the weekly use of topical fluoride are essential. There is a high incidence of oral candidiasis and antifungal drugs are necessary.

Sialorrhoea (Table 42.9)

Some drugs and painful lesions in the mouth increase salivary flow rates. In normal health this is rarely noticed as the excess saliva is swallowed spontaneously. ‘False ptylism’ is more common and is a well-recognised delusional symptom or occurs due to faulty neuromuscular control leading to drool­ing despite normal saliva production. Uncontrollable drooling is usually treated surgically. As the submandibular gland contributes most resting saliva, attention is directed at these glands bilaterally. The submandibular ducts can be mobilised and repositioned in the base of the anterior pillars of the fauces. Alternatively the two glands may be excised.