What is Cystitis?
The word cystitis means inflammation of the urinary bladder although it has often come to be used to describe the symptoms caused by a urinary infection. In fact this is not far from being correct since the most common cause of an inflamed bladder is an infection of the urine within the bladder but there are other causes and these are described below.
Who gets it?
Cystitis caused by infection is extremely common, and can occur at any age in both sexes. However, it is fifty times more common in women than in men, and is commonest amongst sexually active women. At least one in five women will get an attack of it during their lifetime; some studies suggest that approaching half of all women will experience it at some time.
What are the causes of cystitis?
The causes of cystitis due to infection vary according to the age, sex and other factors relating to the individual sufferer so each group is described in turn below:
Otherwise healthy women: The usual cause of cystitis in this group is infection due to germs (bacteria) entering the urinary system from outside, via the urethra (the tube that drains the bladder). This is about 20 centimeters long in men, and only 4 centimeters long in women, so the germs have a shorter distance to travel and cause infection more easily. The bowel germ E. Coli is responsible for 80% of infective cystitis.
Sexual intercourse can cause germs to enter the urethra in spite of good personal hygiene, though poor personal hygiene increases the risk. Many women experience increased bouts of cystitis at the start of the menopause, when the drop in natural oestrogen alters the defense mechanisms in the vagina, increasing risk of infection.
Frequent episodes of cystitis (more than about 6 or so a year) in an otherwise healthy woman may indicate that there is some other underlying cause for the repeated infections. Such underlying causes include an abnormality of the anatomy (structure) of the urinary system, kidney stones, a bladder that is not fully emptying allowing a pool of 'stagnant' urine to form or some other abnormality. If the frequency of infections is high, medical advice should be sought to see if further investigation (see below) is required.
Pregnant women: Infection of the urine in pregnancy is more common than in a non-pregnant woman. Not only this, but the infection may not give the woman any of the usual symptoms of cystitis, is far more likely to lead to infection of the kidney (called pyelonephritis) and, if this does occur, may lead to premature labour or may affect the foetus. For this reason it is usual for pregnant women to have their urine routinely tested for evidence of infection. If there is infection present it is usually quickly treated.
Men: Since urine infections are unusual in men they should be taken seriously. Not only will the physician treat the infection but will consider further investigations to rule out an underlying cause such as a kidney stone, anatomical (structural) abnormality of the urinary system, obstruction such as prostate gland enlargement or other abnormality.
Children: A similar situation to men exists with children i.e. because it is unusual for a child to get a urine infection most doctors will refer a child with a proven urine infection to a specialist for further tests. A urinary infection in a child can sometimes indicate an abnormality of the urinary tract.
About 35% of children who develop a cystitis are found to have a condition called vesico-ureteric reflux where urine from the bladder has a tendency to travel back towards the kidneys up the ureters (the tubes leading from the kidneys to the bladder). This can eventually lead to scarring and damage to the kidneys. Another 5% will be found to have a kidney stone.
Pyelonephritis: Urine created from the kidneys passes down the ureters to the bladder where it is stored before it is passed via the urethra, the tube down the middle of the penis in men or which leads into the lower part of the vagina in women. In cystitis caused by an infection the bacteria are confined to the bladder causing some or all of the symptoms described below. However, occasionally the infection can spread up the ureters to the kidneys. This is called pyelonephritis and can affect one or both kidneys.
The significance of pyelonephritis is that, whereas cystitis is generally at worst a distressing condition, pyelonephritis can be a serious illness. The symptoms of pyelonephritis are all those of cystitis but in addition the patient may complain of pain in the back in the region of the kidneys on one or both sides, a fever and shivers (called rigors). If left untreated pyelonephritis can lead to septicaemia where the infection spreads into the bloodstream requiring treatment with strong antibiotics often administered directly into the veins in hospital.
Other causes of cystitis: Infection elsewhere in the body can occasionally spread to the bladder. Stress and general illness lower resistance to infection and increase the risk of getting cystitis.
A kidney stone can act as a reservoir for infection. Antibiotics do not penetrate a stone, so the germs survive to cause another urine infection. A urinary catheter (a tube to drain urine from the bladder) can also introduce infection.
Rare causes of cystitis include parasitic infection (schistosomiasis), chronic immunological reactions, and as a result of treatment for other conditions (e.g. radiotherapy).
A condition called interstitial cystitis is a recently recognised variant that is difficult to diagnose and treat, but is probably far more common than previously thought. It is estimated that up to half a million people are affected by this in the USA, 90% of them women. Its cause is not fully understood at present, and there is no set way to treat it. More conclusive research is awaited.
What are the symptoms?
Cystitis has a very characteristic set of symptoms, so that it is generally possible to diagnose it from the description alone:
- burning and stinging on passing urine (dysuria)
- passing urine often (frequency)
- experiencing an intense need to pass urine (urgency)
- passing only small amounts at a time
- having to pass urine frequently at night (nocturia)
- bad-smelling or cloudy urine
- pain in the lower abdomen over the bladder
- low back pain
- lack of control over passing urine (incontinence, sometimes)
- low fever
- feeling generally unwell or 'fluey'
- painful sexual intercourse
In children the usual symptoms of cystitis are not always present so diagnosis of a urine infection can be difficult to make. In children a urinary infection can cause the symptoms listed above but may only result in the child being generally unwell with a temperature. A clue may be provided if the child in question starts to wet the bed or become incontinent when they have previously had good bladder control or the parent may notice that the child's urine smells offensive.
Diagnosing urine infections in babies is even more difficult since the only symptoms may be a persistent temperature and the baby being generally unwell and off its feeds. For this reason, although urine infections in babies are unusual, parents and doctors need to be alert to the possibility that an unwell child with no obvious cause for its illness may have an infection in the urine. Sending a sample of urine to the laboratory for analysis will enable the doctor to exclude this as a possibility. It is particularly important for urine infections to be diagnosed in children as early as possible to prevent recurrent or chronic infections from causing kidney damage.
What are the risks?
The major risk is of recurring (chronic) infection. This usually is no more than a repeat bout of misery, but in a small number of cases, it can lead to kidney infection with scarring and permanent damage. The ultimate rare result is a kidney that doesn't work i.e. kidney failure.
This situation is usually prevented by treating urine infections and investigating those patients most likely to develop complications, i.e. babies and children and by ruling out underlying conditions in the young sufferer and men after one infection and in women who have repeated infections.
What tests are useful?
Whilst straightforward urine infections can safely be treated without much or any investigation, it is sometimes necessary to do tests to find out the type of germ causing the infection, and occasionally to monitor the kidney function itself and check for underlying causes.
The tests are:
Urinalysis: a simple surgery test using a sensitive testing stick that can detect pus cells, blood and breakdown products of bacteria in the urine.
Mid Stream Urine (MSU): a sample of urine taken in mid stream (to exclude germs from the urethra which are washed out first) is analysed in a laboratory for the presence and type of bacteria and to guide the doctor as to which antibiotic to give. In babies a similar sample can be obtained for analysis by either catching some urine when they next urinate or by attaching a special bag around the penis or vagina.
A blood test may give an indication of infection or inflammation, and a rough measure of the kidney function.
Ultrasound scan: particularly useful in children because it is simple to undergo. It provides an image of the urinary tract and is useful for looking for structural abnormalities such as an enlarged or shrunken kidney.
Intravenous Urogram (IVU, also known as an Intravenous Pyelogram, IVP): a dye is injected into an arm vein. The kidneys filter it out and allow the urinary system from kidneys to bladder to be clearly shown on x-ray. Without this dye the urinary tract is not normally easily visible on a normal x-ray film. This is useful to see if a kidney is scarred, whether it is working or not, to detect a kidney stone, and to look clearly at the ureters to exclude a narrowing or blockage of these tubes as they lead from the kidneys to the bladder.
Micturating Cystogram: a dye is introduced into the bladder through a catheter. X-rays are taken of the bladder and ureters during the passing of urine to check for reflux (backflow of urine from the bladder up towards the kidneys).
Isotope scan: a very weak radioactive substance is injected into an arm vein. This is filtered by the kidneys. A gamma ray camera detects the radioactivity; linked to a computer that then calculates how accurately each kidney is functioning.
Treatment of Cystitis
Mild cases of cystitis can often be successfully treated with over the counter preparations such as Cymalon, Cystemme, Cytopurin and Cystofem. These generally work by altering the acidity of the urine and making it less hospitable for the invading bacteria which may then die or be flushed out with the urine.
The treatment for most infections that do not respond to these measures is a short course of antibiotics. Underlying causes are treated as appropriate. For example, reflux of urine or a kidney stone can sometimes be treated by surgery.
In situations where someone is prone to repeated episodes of infection for a reason that cannot be corrected, they are sometimes given a low dose of antibiotics every day for a long period of time in order to keep the urine free from infection.
Doryx (Doxycycline), Ilosone (Erythromycin), Keflex (Cephalexin), Sumycin (Tetracycline), Noroxin (Norfloxacin)
What are the treatment side effects?
The infection should begin to improve within 48 hours. If not, it could be that the germs are resistant to the prescribed antibiotic, and contacting the doctor is a good idea.
All antibiotics can cause an allergic rash: if this happens, the doctor should be informed for the record. Diarrhoea and tummy upset are also common, and nearly always subside after the course is finished.
There are a whole host of much rarer side effects which will be listed in the information sheet dispensed with the medication. These are very unlikely to occur, but have to be published by law.
Antibiotics can affect the effectiveness of the oral contraceptive pill.
Additional contraceptive precautions will be needed whilst taking antibiotics until at least seven days after completion of course of antibiotics. This should be discussed with your doctor.
What self-help strategies are there?
- Urinate whenever the urge is felt, and empty the bladder completely. Holding it in gives the bacteria a chance to multiply.
- Wipe genitals from front to back after using the toilet, to prevent sweeping bacteria forward from the anal area.
- Empty the bladder just before and after intercourse. This reduces the risk of introducing bacteria into the urethra during intercourse, and flushes them out afterwards.
- Spermicides can kill the friendly bacteria that live normally in the vagina, keeping unwanted germs at bay. For those prone to cystitis, switching to a different contraceptive may help.
- Cranberry juice appears to prevent bacteria sticking to the bladder wall. Studies in USA have shown that drinking 300ml of cranberry juice per day significantly reduces the number of urine infections in older people in nursing homes. It may also help prevent an infection from developing further once it has started.
- Some sufferers of interstitial cystitis find their symptoms reduce when they follow a low-acid diet by avoiding spicy foods, citrus fruits, tomatoes, coffee, tea, chocolate and alcohol.
- Drink plenty of water: at least eight glasses a day
- Bubble baths can cause irritation of the urethra in some women and are therefore best avoided in these people.
Last updated 17 December 2011