ANORECTAL

Anal itching

Anal swelling

Anorectal pain

Rectal bleeding

Rectal discharge

ANAL ITCHING

The GP overview

Straight out of the list of ‘Embarrassing things to see your GP about’, this is a presentation that patients love to hate. From a GP perspective, it’s one that is generally straightforward to deal with, and effective treatment can usually be offered immediately, much to the patient’s relief.

Differential diagnosis

COMMON

   fungal infection – tinea, thrush

   threadworms

   haemorrhoids

   perianal skin tags

   anal fissure

OCCASIONAL

   poor hygiene

   recurrent or chronic diarrhoea

   perianal warts

   streptococcal perianal infection in children

   trauma from sexual practices – anal intercourse and foreign body insertion

   faecal incontinence, including liquid faecal seepage round impacted scybala

   psoriasis

   secondary to underlying diabetes

   anorectal carcinoma

   chemical irritation: defaecation after a very spicy meal (commonly experienced, rarely presented in practice), bubble baths, soaps, sexual lubricants

RARE

   irritation from perineal decorative body piercing (the ‘Guiche’)

   lichen sclerosus et atrophicus (affects 1 in 100 women, 3 in 10 of these have anal symptoms)

   Crohn’s disease (anal/perianal fistula)

   rectovaginal fistula

   rectal prolapse

   any other cause of rectal discharge or anal swellings – see appropriate chapters

   any serious cause of generalised pruritus – see chapter on anal itching. Rare here because pruritus ani is unlikely to be a presenting complaint

   STDs, e.g. syphilis, gonorrhoea, chlamydia

Ready reckoner

Possible investigations

LIKELY: none.

POSSIBLE: skin swab, FBC, ESR, fasting glucose or HbA1c, proctoscopy.

SMALL PRINT: none.

   In general, unless there are obvious pointers to other more serious disease, investigations would usually only follow after failure of empirical treatment.

   Skin swab for bacteriology may help identify local infection.

   FBC, ESR: may be helpful if Crohn’s disease is suspected, but only as an adjunct to referral as the appropriate management.

   Fasting glucose or HbA1c is essential in recurrent or prolonged cases to exclude diabetes.

   Proctoscopy is quick to do in general practice and can yield valuable information if there is an underlying rectal cause.

TOP TIPS

   Most patients will have attempted self-treatment before presenting in the surgery. This may not always have been appropriate, and could have made the problem worse.

   Unless you are absolutely sure of an obvious cause, it is wise to perform a digital rectal examination to look for rectal causes.

   Perianal warts imply a sexually transmitted disease contact. Refer to GUM clinic for contact tracing and treatment.

   Anal itching is often associated with soreness. If it precludes a rectal examination but there is no obvious primary anal cause for itching, treat symptomatically and bring the patient back to complete the assessment when more comfortable to do so. The patient is unlikely to want to return for this without understanding a clear explanation of why it is necessary.

   Four per cent of women with lichen sclerosus et atrophicus go on to develop vulval cancer. Refer if the vulva is affected, or if treatment fails.

   Refer any suspicious anal lesion for biopsy.

   Be confident to ask about recent sexual encounters and sexual practices if possibly relevant. Sexual history may be important.

ANAL SWELLING

The GP overview

Because of embarrassment on the part of the patient, this may well present as a ‘while I’m here’ symptom. The temptation to make a diagnosis without examination should be resisted – some of the causes (such as perianal abscesses) require urgent attention and others may, rarely, provide something of a surprise (e.g. fistulae, carcinoma).

Differential diagnosis

COMMON

   prolapsed pile

   perianal haematoma

   skin tags

   perianal abscess

   rectal prolapse

OCCASIONAL

   warts

   sebaceous cyst

   sentinel pile

   infected pilonidal sinus

RARE

   hidradenitis

   anal fistula

   carcinoma

Ready reckoner

Possible investigations

In most cases, investigation will be unnecessary. The only exceptions are warts (in which case referral to the local GUM clinic may be required to screen for sexually transmitted disease) and possible carcinoma (in which case biopsy will be performed in secondary care). Also, any suspicion of Crohn’s disease causing perianal disease would be investigated in hospital in the usual way.

TOP TIPS

   This is one of those situations in which a brief history can be taken while the patient is undressing, or during the examination. Atypically for primary care, it’s the examination, rather than the history, which usually provides the definitive diagnosis.

   If a discharge, as well as a lump, is mentioned by the patient, then abscesses, warts, prolapses and fistulae top the list of differentials.

   The patient with an anal swelling who has obvious difficulty walking into the consulting room has either an abscess, a large perianal haematoma or strangulated prolapsed piles.

   Recurrent or multiple fistulae suggest Crohn’s disease.

   If a prolapsed pile is very swollen and painful, it is probably strangulated, and so requires urgent surgical attention.

   A persistent, ulcerating anal swelling, especially in the middle-aged or elderly, requires urgent biopsy to exclude carcinoma.

ANORECTAL PAIN

The GP overview

This is usually severe and distressing. Because of reflex sphincteric spasm, constipation very often follows and increases the pain and suffering further. Adequate examination is also difficult for the same reason; fortunately if a PR exam is too difficult, a visual inspection can often yield the diagnosis.

Differential diagnosis

COMMON

   anal fissure

   thrombosed haemorrhoids/perianal haematoma

   perianal abscess

   proctalgia fugax (PF)

   anorectal malignancy

OCCASIONAL

   levator ani syndrome

   Crohn’s disease

   coccydynia

   descending perineum syndrome

   prostatitis

   ovarian cyst or tumour

   solitary rectal ulcer syndrome

RARE

   anal tuberculosis

   cauda equina lesion

   endometriosis

   trauma

   presacral tumours

Ready reckoner

Possible investigations

LIKELY: none.

POSSIBLE: FBC, ESR/CRP, proctoscopy, faecal calprotectin.

SMALL PRINT: urinalysis, ultrasound, barium enema, other imaging.

   FBC/ESR/CRP: WCC may be raised in abscess and Crohn’s disease. ESR/CRP raised in these and carcinoma.

   Proctoscopy valuable if pain allows (specialist might also take biopsy).

   Faecal calprotectin: may help in diagnosing Crohn’s disease.

   Urinalysis: pus cells and blood may be present in prostatitis or invasive bladder tumour.

   Ultrasound of pelvis if pelvic examination reveals a mass. Barium enema may be necessary to assess possible bowel involvement. In obscure cases, specialists may request other forms of imaging.

TOP TIPS

   If the patient uses dramatic language (e.g. red-hot poker) to describe fleeting pain, is otherwise well and there are no obvious abnormalities on examination, the diagnosis is likely to be proctalgia fugax.

   Examine the patient – the cause is usually a thrombosed pile, anal fissure or an abscess, and these can usually be diagnosed by simple inspection.

   Provide symptomatic relief but remember to deal with any underlying causes – especially constipation.

   Don’t forget to ask about thirst and urinary frequency: recurrent abscesses may be the first presentation of diabetes.

   Preceding weight loss and/or change in bowel habit should prompt a full urgent assessment with carcinoma and inflammatory bowel disease in mind.

   Some perianal abscesses do not result in external swelling. If PR exam is prohibitively painful, consider this possibility – especially if the patient is febrile.

   In florid or recurrent perianal problems, think of Crohn’s disease as a possible cause.

   Remember rarer causes in intractable, constant pain in a patient with no obvious signs on PR.

RECTAL BLEEDING

The GP overview

This is a very common presenting complaint and creates a lot of anxiety in the patient. By far the likeliest causes are haemorrhoids or a fissure, but more sinister pathologies should be considered according to the clinical picture. In children, constipation causing a fissure is the most frequent cause.

Differential diagnosis

COMMON

   haemorrhoids

   anal fissure

   gastroenteritis

   rectal carcinoma

   diverticular disease

OCCASIONAL

   villous adenoma

   trauma (especially non-accidental injury (NAI) if in children)

   anticoagulant therapy

   inflammatory bowel disease

   colonic carcinoma

RARE

   blood clotting disorders (including anticoagulants)

   bowel ischaemia

   angiodysplasia

   intussusception

   Meckel’s diverticulum (in children)

Ready reckoner

Possible investigations

LIKELY: proctoscopy.

POSSIBLE: FBC, ESR/CRP, LFTs, bone biochemistry, U&E, stool for microbiology and faecal calprotectin, sigmoidoscopy, colonoscopy, barium enema.

SMALL PRINT: clotting screen.

   FBC: check for anaemia from acute or chronic bleeding; low platelets may cause or aggravate bleeding.

   ESR/CRP raised in active inflammatory bowel disease and malignancy.

   If malignancy is suspected, LFT, U&E and bone biochemistry are useful early on as a baseline.

   Clotting screen: if clotting disorder a possibility; INR if on warfarin.

   Stool specimen: helpful in the presence of diarrhoea. May show evidence of infective cause (especially Campylobacter) or white cells in inflammatory bowel disease. Faecal calprotectin may be useful in diagnosing IBD.

   Proctoscopy: helpful in primary care in visualising haemorrhoids and proctitis to confirm a clinical diagnosis.

   Sigmoidoscopy or colonoscopy are the most helpful investigations if significant pathology is suspected, and allow biopsy of suspicious lesions.

   Barium enema good for revealing strictures related to the underlying pathology, but if diverticulosis present, may not rule out coexistent neoplasia.

TOP TIPS

   Eighty per cent of rectal tumours are within fingertip range. Always do a PR examination unless, in a child or young adult, the diagnosis is manifestly obvious from the history.

   If blood is on the toilet paper and surface of the motions, the cause is likely to be palpable PR or visible on proctoscopy; if mixed in with the motions, referral for further investigation will be required to make a definite diagnosis.

   In young adults, the diagnosis is usually clear from the history and is likely to be haemorrhoids or a fissure. In such cases, if and when you refer, to allay anxiety, emphasise that this is for treatment rather than investigation.

   The presence of diarrhoea with rectal bleeding in young or middle-aged adults suggests gastroenteritis (especially Campylobacter) or colitis.

   Change of bowel habit and weight loss with rectal bleeding are ominous symptoms which should prompt urgent referral.

   If a child is presented with rectal bleeding without any clear cause, consider NAI.

   The presence of haemorrhoids does not necessarily clinch the diagnosis – another lesion may be present, especially in the elderly.

   A brisk, painless haemorrhage in an elderly patient is likely to be caused by diverticular disease. Significant amounts of blood can be lost, so assess urgently with a view to admission.

RECTAL DISCHARGE

The GP overview

This unpleasant symptom causes considerable embarrassment and inconvenience. The presenting complaint may well be itching rather than a history of discharge or dampness. The most common causes are benign, but serious pathology is sufficiently likely to warrant thorough examination.

Differential diagnosis

COMMON

   haemorrhoids

   anal fissure

   rectal prolapse

   proctitis

   perianal warts

OCCASIONAL

   rectal carcinoma

   IBS

   anal/perianal fistula (may be associated with Crohn’s disease)

   villous adenoma

   poor anal hygiene

   solitary rectal ulcer syndrome

RARE

   anal tuberculosis

   anal carcinoma

   STD, e.g. syphilis, gonorrhoea, chlamydia

   AIDS

Ready reckoner

Possible investigations

LIKELY: swab if purulent.

POSSIBLE: FBC, ESR/CRP, U&E and direct visualisation techniques (see below).

SMALL PRINT: STD screen.

   Anorectal swab for bacteriology if pus and local inflammation is present.

   FBC/ESR/CRP: WCC and ESR/CRP raised in inflammatory bowel disease.

   U&E: profuse mucus discharge from a villous adenoma can cause hypokalaemia.

   Proctoscopy easily done in practice and guides management and referral.

   Sigmoidoscopy allows definitive examination and biopsy of suspicious lesions or inflammation.

   STD screen – if STD suspected.

TOP TIPS

   This symptom is likely to be associated with embarrassment. A clinical examination is important – so help the patient overcome any reticence with a sympathetic approach.

   Normal secretions from the anus should not be discounted – from perianal sweat glands and the anal glands themselves. This can sometimes cause a significant problem, particularly in the obese and those with poor anal hygiene.

   In women, the source of the discharge may be unclear. Speculum examination and protoscopy may be required to resolve any doubt.

   Sexual history may be important. Don’t be coy in asking about recent sexual encounters and sexual practices if relevant.

   Rectal discharge in the elderly suggests carcinoma unless proved otherwise.

   A history of diarrhoea and abdominal pain suggests bowel pathology. Ulcerative colitis or Crohn’s disease is most likely in this context.

   Any ulcerating lesion in the perianal area other than an obvious haemorrhoid should prompt referral for biopsy.