Pyelonephritis is a bacterial infection that affects the kidney. A chronic form is sometimes seen in babies or children. However, this infection is mainly diagnosed in women between the ages of 15 and 65. Acute pyelonephritis most often occurs in women as a result of untreated or poorly treated cystitis. Its management is essentially based on the use of antibiotics.

Definition of pyelonephritis

Pyelonephritis is a medical term used for associated pyelitis and nephritis. These are two types of bacterial infections occurring in the kidney: pyelitis affects the pelvis while nephritis refers to an infection of the renal parenchyma. Both of these structures play a role in urinary excretion.

Types of pyelonephritis

Two forms of pyelonephritis have been identified:

• acute pyelonephritis, often referred to as acute adult pyelonephritis, which is usually the consequence of another bacterial infection;
• chronic pyelonephritis, a form that can be related to anatomical abnormalities and can be seen as early as the baby is developing.

Causes of pyelonephritis

Pyelonephritis can have different causes including:

• an ascending infection in many cases, which is a complication of another bacterial infection such as untreated or poorly treated cystitis: the germs travel up along the ureter (channel connecting the kidney to the bladder) and spread to the kidney;
• the presence of urinary stasis which promotes the development of an infection in the kidney: it is the consequence of an obstruction of the urinary tract which may be caused by a narrowing of the urethra (outlet duct of the bladder), urinary stones, a bladder tumor or benign prostatic hyperplasia;
• anatomical abnormalities that cause urinary reflux in the pelvis and promote the development of an infection.

Diagnosis of pyelonephritis

The diagnosis of pyelonephritis can be based on:

• a clinical examination combined with a questioning in order to assess the perceived symptoms;
• a cytobacteriological examination of the urine (ECBU), which can sometimes be combined with other laboratory tests;
• medical imaging tests such as kidney ultrasound, abdominal x-ray, or CT scan to identify an obstacle or complications;
• a complete blood count, or blood count.

People affected by pyelonephritis

This bacterial infection is more common in women between the ages of 15 and 65. Its acute form is often diagnosed with untreated or poorly treated cystitis.

However, it can also be diagnosed in younger and older people of all sexes. Pyelonephritis can be seen in older men with benign prostatic hyperplasia. The chronic form can be diagnosed in babies or children.

Factors favoring pyelonephritis

Several factors seem to increase the risk of pyelonephritis. These are mainly risk factors for urinary tract infections:

• transit disorders;
• a lack of hydration;
• sexual relations,
• premenstrual and postmenstrual periods;
• lack of or excess hygiene in the intimate area;
• genital prolapse;
• menopause ;
• the pregnancy ;
• diabetes ;
• l’immunodépression.

Signs of a urinary tract infection

Acute pyelonephritis is often accompanied by a urinary tract infection. It can thus manifest itself by:

• burning during urination;
• a frequent urge to urinate (pollakiuria);
• smelly or cloudy urine with pus present (pyuria);
• the presence of blood in the urine (hematuria).

Lower back pain

Unilateral pain in the lumbar area is often observed. It can spread to the genitals. Nevertheless, the pain is sometimes absent, especially in cases of chronic pyelonephritis.

Fever

A fever is a common sign of infection. However, pyelonephritis can be seen without fever, especially in chronic pyelonephritis.

Support can be based on:

• antibiotic therapy in the majority of cases, with the use of a single antibiotic or a combination depending on the severity of the pyelonephritis;
• the use of analgesics and antispasmodics in some cases to relieve certain symptoms;
• hospitalization in the event of complicated pyelonephritis and / or occurring in fragile people.

It is possible to prevent some cases of pyelonephritis by limiting the risk of urinary tract infection as much as possible. For this, several tips are generally given:

• adequate hydration;
• regular urination;
• urination after intercourse;
• appropriate personal hygiene;
• front-to-back wiping when saddling;
• good eating habits for digestive and intestinal comfort.