Острый и хронический пиелонефрит: симптомы, диагностика и лечение.

Signs and symptoms of acute pyelonephritis generally develop rapidly over a few hours or a day. It can cause high fever, pain on passing urine, and abdominal pain that radiates along the flank towards the back. There is often associated vomiting. Chronic pyelonephritis causes persistent flank or abdominal pain, signs of infection (fever, unintentional weight loss, malaise, decreased appetite), lower urinary tract symptoms and blood in the urine. Chronic pyelonephritis can in addition cause fever of unknown origin. Furthermore, inflammation related proteins can accumulate in organs and cause the condition AA amyloidosis. Physical examination may reveal fever and tenderness at the costovertebral angle on the affected side.

Analysis of the urine may show signs of urinary tract infection. Specifically, the presence of nitrite and white blood cells on a urine test strip in patients with typical symptoms are sufficient for the diagnosis of pyelonephritis, and are an indication for empirical treatment. Blood tests such as a complete blood count may show neutrophilia. Microbiological culture of the urine, with or without blood cultures and antibiotic sensitivity testing are useful for establishing a formal diagnosis,

If a kidney stone is suspected (e. g. on the basis of characteristic colicky pain or the presence of a disproportionate amount of blood in the urine), a kidneys, ureters, and bladder x ray (KUB film) may assist in identifying radioopaque stones. All stones are detectable on CT scans except very rare stones composed of certain drug residues in the urine. In patients with recurrent ascending urinary tract infections, it may be necessary to exclude an anatomical abnormality, such as vesicoureteral reflux or polycystic kidney disease. Investigations used in this setting include kidney ultrasonography or voiding cystourethrography.]] Ultrasound findings that indicate pyelonephritis are enlargement of the kidney, edema in the renal sinus or parenchyma, bleeding, loss of corticomedullary differentiation, abscess formation, or an areas of poor blood flow on doppler ultrasound. However, ultrasound findings are seen in only 20% to 24% of people with pyelonephritis.

Acute pyelonephritis is an exudative purulent localized inflammation of the renal pelvis (collecting system) and kidney. The kidney parenchyma presents in the interstitium abscesses (suppurative necrosis), consisting in purulent exudate (pus): neutrophils, fibrin, cell debris and central germ colonies (hematoxylinophils). Tubules are damaged by exudate and may contain neutrophil casts. In the early stages, the glomerulus and vessels are normal. Gross pathology often reveals pathognomonic radiations of bleeding and suppuration through the renal pelvis to the renal cortex.

In people suspected of having pyelonephritis, a urine culture and antibiotic sensitivity test is performed, so therapy can eventually be tailored on the basis of the infecting organism. In people who do not require hospitalization and live in an area where there is a low prevalence of antibiotic resistant bacteria, a fluoroquinolone by mouth such as ciprofloxacin or levofloxacin is an appropriate initial choice for therapy. Intravenous fluids may be administered to compensate for the reduced oral intake, insensible losses (due to the raised temperature) and vasodilation and to optimize urine output. Percutaneous nephrostomy or ureteral stent placement may be indicated to relieve obstruction caused by a stone. Children with acute pyelonephritis can be treated effectively with oral antibiotics (cefixime, ceftibuten and amoxicillin/clavulanic acid) or with short courses (2 to 4days) of intravenous therapy followed by oral therapy. If intravenous therapy is chosen, single daily dosing with aminoglycosides is safe and effective. Treatment of xanthogranulomatous pyelonephritis involves antibiotics as well as surgery. Removal of the kidney is the best surgical treatment in the overwhelming majority of cases, although polar resection (partial nephrectomy) has been effective for some people with localized disease. Watchful waiting with serial imaging may be appropriate in rare circumstances.

If no improvement is made in one to two days post therapy, inpatients should repeat a urine analysis and imaging. Outpatients should check again with their doctor.

There are roughly 1213 cases annually per 10,000 population in women receiving outpatient treatment and 34 cases requiring admission. In men, 23 cases per 10,000 are treated as outpatients and 12 cases/10,000 require admission. Young women are most often affected. Infants and the elderly are also at increased risk, reflecting anatomical changes and hormonal status.

According to a 2015 meta analysis, vitamin A has been shown to alleviate renal damage and/or prevent renal scarring.

The term is from Greek πύελο|ς pýelo|s, "basin" + νεφρ|ός nepʰrós, "kidney" + suffix itis suggesting "inflammation". A similar term is "pyelitis", which means inflammation of the renal pelvis and calyces. In other words, pyelitis together with nephritis is collectively known as pyelonephritis.

The word pyelonephritis is formed by the Greek roots pyelo from πύελος (púelos) renal pelvis and nephro from νεφρός (nephrós) kidney together with the suffix itis from ῖτις ( itis) used in medicine to indicate diseases or inflammations.