Proctitis

Inflammation is sometimes limited to the rectal mucosa; in others it is associated with a similar condition in the colon (proctocolitis). The inflammation can be acute or chronic. The symptoms are tenesmus, the passage of blood and mucus and, in severe cases, of pus also. Although the patient has a frequent intense desire to defecate, the amount of faeces passed at a time is small. Acute proctitis is usually accompani­ed by malaise and pyrexia. On rectal examination the mucosa feels swollen and is often exceedingly tender. Proctoscopy is seldom sufficient and sigmoidoscopy is the more valuable method of examination. If the diagnosis is confirmed, colonoscopy with multiple biopsies is mandatory, so as to determine the extent of the inflammatory process. Skilled pathological assistance is required to establish or exclude the diagnosis of specific infection by bacteriological examination and culture of the stools, examination or scrapings or swabs from ulcers, and serological tests. When early carcinoma cannot be excluded, biopsy is necessary.

Nonspecific proctitis is an inflammatory condition affecting the mucosa and, to a lesser extent, the submucosa, confined to the terminal rectum and anal canal. It is the most common variety. In 10 per cent of cases the condition extends to involve the whole colon (total ulcerative colitis).

  Aetiology. This is unknown. The concept that the condition is a mild and limited form of ulcerative colitis (although actual ulceration is often not present) is the most acceptable hypothesis.

Clinical features. The patient is usually middle-aged, and complains of slight loss of blood in the motions. Often the complaint is one of diarrhoea, but on closer questioning it transpires that usually one relatively normal action of the bowels occurs each day, although it is accompanied by some blood. During the day the patient attempts to defecate, with the passage of flatus and a little blood-stained faecal matter, which is mistakenly interpreted as diarrhoea. On rectal examination, the mucosa feels warm and smooth. Often there is some blood on the examining fin­ger. Proctoscopic and Sigmoidoscopic examination shows inflamed mucous membrane of the rectum, but usually no ulceration. The inflammation usually extends for only 12.5—15 cm from the anus, the mucosa above this level being quite normal.

Treatment. Although, fortunately, the condition is usually self-limiting, much relief may be obtained from the use of sulphasalazine (Salazopyrin) and its more active component 5-ASA (Asacol), acetarsol suppositories or prednisolone retention enemas. Milk should be rigidly excluded from the diet. In very severe resistant cases, oral steroids may have to be used to obtain remission. Rarely, surgical treatment is used as a last resort when the patient is desperate for relief of symptoms.

Ulcerative proctocolitis. Proctitis is present in a high percentage of cases of ulcerative colitis, and the degree of severity of the rectal involvement may influence the type of operative procedure (see Chapter 57).

Proctitis due to Crohn’s disease. Crohn’s disease can occasionally affect the rectum, although classically it is spared. Sigmoidoscopic char­acteristics differ from those in nonspecific proctitis. The inflammatory process tends to he patchy rather than confluent and there may he fissuring, ulceration and even a cobblestone appearance. Rectal Crohn’s disease is often associated with severe perineal disease characterised by fistulation. Skip lesions are also often present in the rest of the colon or small bowel, or both.

Proctitis due to specific infections

Clostridium difficile. An acute form of proctocolitis by infection with C. difficile can follow broad-spectrum antibiotic administration (espe­cially lincomycin). A ~membrane’ can sometimes he seen on proctoscopy (‘pseudomernbranous’ enterocolitis).

Bacillary dysentery. The appearance is that of an acute purulent proctitis with multiple small, shallow ulcers. The examination of a swab taken from the ulcerated mucous membrane is more certainly diagnostic than is a microscopical examination of the stools. Proctological examination is painful; agglutination tests may render it unnecessary.

Amoebic dysentery. The infection is more liable to be chronic, and exacerbations after a long period of freedom from symptoms often occur. Proctoscopy and sigmoidoscopy are not painful. The appearance of an amoebic ulcer is described in Chapter 57. Scrapings from the ulcer should be immersed in warm isotonic saline solution and sent to the laboratory for immediate microscopical examination.

Amoebic granuloma. This presents as a soft mass, usually in the recto­sigmoid region. This lesion is frequently mistaken for a carcinoma. Sigmoidoscopy shows an ulcerated surface, hut the mass is less friable than a carcinoma. A scraping should he taken, preferably with a small, sharp spoon on a long handle, and the material sent for immediate microscopical examination, as detailed above. If doubt exists, a provocative dose of emetine may cause cysts of the amoebae to appear in the stools. A biopsy can also help. Treatment is as described in Chapter 57.

Amoebic granuloma of the rectum is from time to time encountered in a patient who has never visited a country in which the disease is endemic. Persons living in old people’s institutions ate liable to harbour this deceptive lesion.

Tuberculous proctitis. This is nearly always associated with active pulmonary tuberculosis ulceration of the anus. Submucous rectal abscesses burst and leave ulcers with an undermined edge. A hypertrophic type of tuberculous proctitis occurs in association with tuberculous peritonitis, or tuberculous proctitis occurs in association with tuberculous peritonitis or tuberculous salpingitis. This type of tuberculous proctitis requires biopsy for confirmation of the diagnosis.

Gonococcal proctitis. Gonococcal proctitis occurs in both sexes as the result of rectal coitus, and in the female from direct spread from the vulva. In the acute stage, the mucous membrane is hyperaemic and thick pus can he expressed as the proctoscope is withdrawn. In the early stages, the diagnosis can be readily established by bacteriological examination, hut later, when the infection is mixed, it is mote difficult to recognise. Specific treatment is so effective that local treatment is unnecessary.

Lymphogranuloma inguinale. The modes of infection are similar to those of gonoccocal proctitis, hut in the female infection spreading from the cervix uteri via lymphatics to the pararectal lymph nodes is common. The proctological findings are similar to those of gonococcal proctitis. The diagnosis of lymphogranuloma in inguinale should he suspected when the inguinal lymph nodes are greatly enlarged, although the enlargement may be subsiding by the time proctitis commences (Chapter 67). Primary syphilis. A primary chancre may occur inside the anus (Chapter 64) — a paradox — ‘a painless anal fissure’.

Acquired immunodeficiency syndrome (AIDS).

 AIDS may present with a particularly florid type of proctitis. In such patients unusual organisms such as cytomegalovirus (CMV) are often found on culture.

‘Strawberry’ lesion of the rectosigmoid. This is due to an infection by Spirochaeta vincenti and Bacillus fusiform is. The leading symptom is diarrhoea, often scantily blood stained. Occasionally the diagnosis can he made by the demonstration of the specific organisms in the stools. More often sigmoidoscopy is required. The characteristic lesion is thickened, somewhat raised mucosa with superficial ulceration in the region of the rectosigmoid. The inflamed mucous membrane oozes blood at numerous pin-points, giving the appearance of an over-ripe strawberry. A swab should be taken from the lesion and examined for Vincent’s and fusiform organisms. Swabs from the gums and the throat are also advisable.

Treatment. Acetarsol suppositories together with vitamin C ate almost specific.

Rectal bilharziasis. Rectal bilharziasis is caused by Schistosoma mansoni, which is endemic in many tropical and subtropical countries, and particularly in the delta of the Nile.

Stage 1. A cutaneous lesion develops at the site of entrance of the cercairae (parasites of freshwater snails).

Stage 2 is characterised by pyrexia, urticaria and a high eosinophilia. Both of these stages ate frequently overlooked.

Stage 3 is due to deposition of the ova in the rectum (much more rare­ly in the bladder, Chapter 65) and is manifested by bilharzial dysentery. On examination in the later stages, papillomas are frequently present. The papillomas, which are sessile or pedunculated, contain the ova of the trematode, the life-cycle of which resembles that of Sehistosoma haematobium.

Untreated, the rectum becomes festooned, and prolapse of the diseas­ed mucous membrane is usual. Multiple fistulae-in-ano are prone to develop.

General treatment of bilharziasis mansomi. Compounds not contain­ing antimony include niridazole (Ambilhar) in cases of infestation with S. haematobium or S. mansomi (not S. japonicum or in those with heart, mental or liver disease). Dose is 25 mg/kg body weight daily in two divided doses for 5—7 days. Hycanthone, lucanthone and oxamniquine are other compounds with weight-related single doses given by deep intramuscular (i.m.). injection, and all have toxic side effects. Metriphonate is an organophosphorous compound, effective against S. haematobium only and must he handled with care. Praziquantel (Biltricide) has proved a major advance in drug therapy, and is highly effective against all schistosome species. It is generally given as a single oral dose of 40 mg/kg for S. haematobium and S. mansomi, and for S. japonicum a higher dose of 60 mg/kg is given as two or three divided doses throughout 1 day.

Compounds containing antimony, either as the salts, tartar emetic (antimony potassium tartrate) and sodium salt given intravenously (iv.)., or antimony lithium thiomalate, sodium antimonygluconate, stibogluconate and stibocaptate (Astiban) may still be required.

Local treatment. When the papillomas persist in spite of general treatment, they must be treated in the same manner as other papillomas by local destruction.

Proctitis due to herbal enemas. This is a well-known clinical entity to those practising in tropical Africa. Following an enema consisting of a concoction of ginger, pepper and bark, administered by a witch doctor, a most virulent proctitis sets in. Pelvic peritonitis frequently supervenes.

Not infrequently, a complete gelatinous cast of the mucous membrane of the rectum is extruded. Very large doses of morphine, together with streptomycin, often prevent a fatal issue if commenced early (Bowesman). Temporary colostomy is often advisable.

Treatment

General treatments should include bed rest in extreme cases. The stools should be kept soft with Isogel. Suppositories of 5-ASA are often beneficial. The specific treatments for the dysenteries, tuberculosis, gonorrhea, lymphogranuloma inguinale and syphilis are described in the appropriate sections of this book.