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see nephritisnephritis
, inflammation of the kidney. The earliest finding is within the renal capillaries (glomeruli); interstitial edema is typically followed by interstitial infiltration of lymphocytes, plasma cells, eosinophils, and a small number of polymorphonuclear leukocytes.
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an inflammation of the calyxes, pelvises, and parenchyma of the kidneys caused by the colon bacillus, staphylococcus, Pseudomonas aeruginosa, Proteus, and by other microorganisms. Primary, acute or chronic, and unilateral or bilateral forms of pyelonephritis are distinguished from secondary pyelonephritis, which is preceded by other diseases of the kidney and urinary tract. The morphologic changes associated with the disease take the form of clusters of cellular infiltrates. In chronic pyelonephritis, the kidney surface exhibits multiple cicatricial retractions. The cortical layer is thin and uneven.

Acute pyelonephritis often begins with fever, chills, and pain in the lumbar region. Urination is painful and frequent, and there may be headaches, nausea, and vomiting. Nitrogenous residues may increase in the blood in the early stages. The urine contains pus, red blood cells, albumin, and numerous bacteria, more than 100,000 per ml of urine. Treatment consists of antibacterial therapy with sulfanilamides, nitrofurans, and antibiotics. During the stage of fever, the intake of protein should be limited. Later the diet may be normal, with a copious intake of fluids, application of heat to the lumbar region, and antispasmodics.

The presence of chronic pyelonephritis is often revealed during urinalysis or the taking of blood pressure. The patient may complain of general weakness, headache, lack of appetite, pain in the lumbar region, and increased frequency of urination. The skin is pale and dry. The disease’s progress is bilateral. The urine’s specific gravity decreases and hypertension frequently develops, as does renal insufficiency. Diagnostic methods include urinalysis and examination of the renal functions, roentgenography, the use of radioisotopes, and occasionally biopsy of the kidneys. Treatment consists of prolonged antibacterial therapy with such drugs as nitrofurans, sulfanilamides, antibiotics, and NegGram. In the case of hypertension, hypotensive drugs are prescribed and the impaired urine flow is normalized. If such contraindications as renal insufficiency, obstruction of the urinary tract, and marked hypertension are absent, treatment in the Truskavets, Essentuki, Zheleznovodsk, or Sairme sanatoriums may be prescribed.


Pytel’, A. Ia., and S. D. Goligorskii. Pielonefrit. Moscow, 1961.
Ratner, N. A. Bolezni pochek i gipertoniia, 2nd ed. Moscow, 1971.



The disease process resulting from the effects of infections of the parenchyma and the pelvis of the kidney. Also known as interstitial nephritis.
References in periodicals archive ?
Untreated pyelonephritis can cause severe damage to the kidney resulting in emphysematous pyelonephritis.
Vabomere (meropenem and vaborbactam) is indicated for the treatment of patients 18 years of age and older with complicated urinary tract infections including pyelonephritis caused by the following susceptible microorganisms: Escherichia coli, Klebsiella pneumoniae, and Enterobacter cloacae species complex.
Emphysematous pyelonephritis is a rare, necrotizing infection characterized by gas production in the renal parenchyma (17).
The multicentre RCT by Garin et al evaluated 218 children (age three months to 18 years) with a history of pyelonephritis and some with Grade I--III VUR randomized to either CAP (nitrofurantoin or co-trimoxazole) or no antibiotic.
Therefore, the present investigation was carried out to study the prevalence and antibiotic resistance pattern of MRSA isolated from immunosuppressive patients suffered from pyelonephritis.
coli antimicrobial resistance among patients with acute pyelonephritis who sought care at a US emergency department (ED)-based sentinel research network.
Methods: A series of 42 patients presenting with obstructive pyelonephritis due to proximal ureteral stones larger than 1.
Although ultrasound can be used for initial assessment of patient with complicated UTI and suspected pyelonephritis, and can raise suspicion or diagnose XGP, a preferred radiologic modality is CT abdomen and pelvis with contrast as it provides highly specific imaging findings and accurate assessment of the renal involvement along with extrarenal extent of disease.
Acute pyelonephritis consists of 2/3 of febrile UTIs in early childhood.
Coronal view of CT showed obvious swollen and fat stranding of left kidney, which indicated acute pyelonephritis [Figure 2].
The report provides a snapshot of the global therapeutic landscape of Pyelonephritis
Therefore, the diagnosis of acute pyelonephritis (APN) should be made timely, accurate treatment should be administered, risk factors should be determined and the patient should be referred accordingly.