Pyelonephritis has a very typical presentation which is the classical triad of symptoms. This includes fever, costovertebral angle pain or abdominal pain and nausea or vomiting.

The onset is very rapid and very soon. Very rarely do symptoms take long to develop and maybe present for a few weeks before patient seeks medical care.

Along with the classical triad of symptoms, varying degrees of cystitis will be experienced by the patient. Typical signs of urinary tract infection (UTI) are increased frequency of micturition day and night, dysuria, haematuria, smelly and cloudy urine and lastly, suprapubic pain. These suggest lower urinary tract infection. Loin pain with fever suggest ascent of infection where there is involvement of kidney. So in many cases, the initial symptoms may only be UTI symptoms confined to the lower urinary tract [5].

In small children who cannot complain of dysuria, symptoms are often atypical. The possibility should always be considered in a fretful, febrile sick child who fails to thrive. If there is no underlying urinary tract abnormality it rarely leads to chronic cases in children above 5 years of age.

In elderly patients, apart from typical symptoms delirium may be present.

Chronic pyelonephritis usually presents with continuous abdominal pain along with persistent fever. Along with that anorexia, loss of weight, malaise and fever, chills will be present. Many cases of pyelonephritis may only present with pyrexia of apparently unknown origin. Haematuria and proteinuria is also common in chronic cases. Blood urea nitrogen is raised in most cases.

Complicated cases of pyelonephritis arise when there are structural or functional abnormalities with the urinary system. Frequent urinary instrumentation can also lead to this condition [6].

Severe complicated cases can lead to septicaemia, hypotension and shock if left untreated.

Diagnosis can be done on three parameters mainly history taking, physical examination and lastly, laboratory tests. A complete history regarding the onset, duration and severity of symptoms should be taken.

Patient may be febrile [7] and other vital parameters maybe affected. Tachycardia and hypotension may occur in severe cases. Patient may appear dehydrated and uncomfortable.

Abdominal examination will show costovertebral angle tenderness which can be either unilateral or bilateral. Lumbar tenderness and abdominal guarding is mostly always present. Suprapubic tenderness will be usually present. In women, pelvic examination has to be done to rule out any other pathology.

Laboratory tests in the form of urine analysis [8], microscopy, and culture should be done. Urine reports will always show signs of infection mainly presence of bacteria and increase white blood cells. Pus cells may be there. Culture and sensitivity is done for correct diagnosis and treatment [9]. Blood urea nitrogen, creatinine, and urea levels tend to be elevated.

Imaging techniques done are plain radiographs which help to detect stones. Ultrasound may be used to detect tumours, blockages and abscesses. In addition, CT scan maybe taken for complete detailed images of kidney and urinary tract and their surrounding tissues.

The treatment depends on the severity of symptoms. The mainstay of treatment is antibiotics. Hospitalization is often required as the infection gets diagnosed late.

Antibiotics are given for a minimum of 7 days. Intravenous administration may be given initially to start the treatment. This ensures that the medication reaches the kidney. A high daily fluid intake (2 litres) is advised. After 5 days of treatment urine analysis studies should be repeated [10].

If the patient is severely ill, hospitalization is needed with intravenous administration of medication, switching to a further 7 day oral therapy as symptoms improve. Intravenous fluids may be required for a good urine output.

In patients presenting for the first time with high fever and loin pain suddenly, an urgent renal ultrasound should be done to exclude abscess formation. Most cases of pyonephrosis require drainage by a percutaneous nephrostomy.

Pre-treatment and post-treatment urine culture is mandatory to confirm the diagnosis and identify whether recurrent infection is a relapse or reinfection.

A single episode of acute pyelonephritis will rarely cause any renal scarring or damage. Recovery rate is very good with appropriate antibiotic therapy. The key to full recovery is early diagnosis and prompt treatment. Recovery in acute cases is within days to weeks.

Repeated attacks can lead to chronic pyelonephritis, which can result in various complications. In complicated cases, recovery rates depend on patient’s age and whether any other renal pathology is involved.

It is important to take the complete course of antibiotics. Long term monitoring is required for recurrent cases. Prophylactic treatment can be given.

Bacteria commonly found in stool are the main etiological agents from this infection. Most commonly responsible bacteria are Escherichia coli, Proteus, Klebsiella and Pseudomonas. E. coli is found in 85% of cases. Gram-positive agents like Enterococcus Faecalis and Staphylococcus Aureus can also cause pyelonephritis.
Most of the cases of pyelonephritis start with cystitis and prostatitis [2].

A number of other risk factors are also associated which increase and maintain the infection; mainly individuals with structural abnormalities in the urinary tract and vesicoureteral reflux. Mechanical obstructions in the form of kidney stones, benign tumours or frequent catheterization are also important risk factors.

Sexual activity with different partners can also predispose to frequent urinary infections.

Systemic diseases like diabetes mellitus or immunocompromised individuals have higher chances of developing pyelonephritis.

Uncomplicated cases of pyelonephritis mainly affect women more than men. These are usually acute episodes. The incidence is about 12-13 cases per 10000 in women and 2-3 cases per 10000 in men. Women are affected more due to a shorter length of urethra and the infection occurs in sexually active women more frequently [3].

Pyelonephritis with complications occurs more in elderly men. Since the presentation of symptoms is atypical in infants and children, it is difficult to demonstrate such cases. Though it’s more common in men than women, the difference reduces as age progresses, especially after 65 years, when it is equal.

Infection in most of the cases is due to bacteria from the patient’s own bowel flora, E. coli being the commonest causative agent.
Transfer to the urinary tract maybe via the bloodstream, the lymphatics or through the transurethral route. Transurethral route is the most common mode of transport for these bacteria. Three important steps play a role in the pathogenesis:

• Periurethral colonization with bacteria which is facilitated by adhesion of bacteria to uroepithelial surfaces by pili or fimbriae present on the bacteria. Other factors which maintain this vicious circle are a lack of personal hygiene. Local infections have been incriminated too.
• Transurethral passage of microoraganisms along the urethra to the bladder. Sexual intercourse and catherisation facilitate this transport. This occurs easily in females due to shorter length of urethra compared to males [4].
• Establishment of bacteria in the bladder which is the most important aspect of this pathogenesis. As a result, the bacteria grow and multiply. Normally, urine in bladder is sterile due to bladder defence mechanisms.

This extension of infection is made easy by vesicoureteric reflux and dilated hypotonic ureters. Once infection is established, it can easily pass up or down the system.

Recurrent UTI infections should be prevented by improving fluid intake, improving micturating habits, and personal hygiene after sexual intercourse. Witholding of urine can lead the infection to grow. Women should void urine immediately after sexual intercourse to prevent ascent of bacteria. After micturition women should wipe from back to front. Avoidance of constipation may improve bladder emptying.

Recurrent UTI’s should be thoroughly investigated for any underlying pathology. Long term low dosage prophylaxis can be given for a period of 6 – 12 months in patients with repeated UTI’s with nitrofurantoin.

Pyelonephritis is an infection of the kidney which results in an inflammation of the renal parenchyma, calyces and renal pelvis. Pyelonephritis is mainly a result of a urinary tract infection.
Most of the urinary infections involve only urethra and urinary bladder but when it progresses up to involve the kidney and ureters, pyelonephritis occurs. Pyelonephritis is a result of urinary tract infections wherein an acute episode of fever, nausea, vomiting and abdominal pain radiating to the back may present suddenly [1].

If left untreated it can lead to severe sepsis, shock, delirium and ultimately multi organ failure. Recurrent infections cause considerable mortality and morbidity. In complicated cases, it can lead to severe renal disease which can lead to renal failure. It can also lead to permanent renal scaring. It’s a common source of life threatening Gram-negative septicaemia.

Chronic pyelonephritis usually results from recurrent renal infections, vesicouretral reflux and other structural abnormalities in urinary tract. This usually happens in elderly or infants. Complications always arise with chronic pyelonephritis.
In men, benign prostatic hyperplasia is an important predisposing factor.

Pyelonephritis needs to be treated immediately with antibiotic therapy to prevent life threatening complications. Recurrence and reinfection can occur.

Pyelonephritis is an infection of the kidney which is caused by bacteria that reach the kidneys from the urinary bladder. Pyelonephritis is mostly a result of a urinary tract infection.

Women are at a higher risk of getting pyelonephritis due to easier access for bacteria to enter primarily due to shorter length of urethra. This condition is more common in sexually active women.
The most common cause is a bacteria which is normally present in the faeces. This bacteria E. coli travels upwards towards the urinary tract and causes infection which ultimately reaches the kidneys. This results in a severe infection which can travel any way through the urinary system.

The main symptoms include fever and pain in the back which may radiate till the abdomen. Difficulty in passing urine, frequent urination along with foul smelling cloudy urine may also be present. In severe complications, the infection may spread to the whole body which can result in multiorgan failure.

Early diagnosis should be done for complete recovery. If any of the above symptoms are present immediate medical help should be sought. A medical care provider will be able to diagnose the case with a simple case taking and clinical examination. Laboratory tests in the form of urine tests will be done along with imaging techniques to detect the severity. CT scans may be done for complete study of kidneys.

Treatment is with immediate antibiotic therapy along with increased fluid intake. Complete course of antibiotic should be taken for complete recovery. Urine should be tested post treatment to prevent any reinfection or relapse.

In all cases there is complete recovery unless there is some complication mainly any abnormality in the urinary tract and system. Chronic cases tend to reoccur for which preventive therapy is given.

At least 6-8 glasses of water should be taken daily. Women should urinate before bed time and after sexual activity. Personal hygiene should be maintained after urination.

Early detection and immediate treatment is the most important aspect in controlling the infection and preventing a relapse or reinfection.

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