Pyelonephritis

Escherichia coli is a cause of enteritis in young infants and the young of farm animals, where it can cause diarrhoea and fatal dehydration. It is a common infectant ofthe urinary tract and bladder in humans, and is a cause of pyelitis, pyelonephritis and cystitis. 

White blood cells or casts (acute interstitial nephritis or severe pyelonephritis)... 

Patients may or may not be in acute distress. In early stages of disease, the patient may complain of obstructive voiding symptoms. If untreated, in late stages of disease the patient may complain of irritative voiding symptoms, or acute urinary retention, which is painful due to maximal distention of the urinary bladder. Also, the patient may be symptomatic of disease complications, including urosepsis, pyelonephritis, cystitis, or overflow urinary incontinence. 

Bacteriuria, or bacteria in the urine, does not always represent infection. For this reason a number of quantitative diagnostic criteria have been created to identify the amount of bacteria in the urine that most likely represents true infection (hence the term significant bacteriuria ). These are shown in Table 76-1. Furthermore, UTIs are classified as lower tract or upper tract disease. Patients will present differently with upper versus lower tract disease, and upper tract disease is thought of as a much more severe infection, as patients are more likely to be admitted to the hospital with upper urinary tract disease than lower tract disease. An example of lower tract infection is cystitis. Cystitis refers to the syndrome associated with a UTI involving dysuria, frequency, urgency, and occasional suprapubic tenderness. An example of upper urinary tract disease is pyelonephritis. Pyelonephritis is an inflammation of the kidney usually due to infection. Frequently, patients with uncomplicated UTI are treated as outpatients, while those patients with complicated UTIs are treated as inpatients. 

The newer quinolones have a greater spectrum of activity. These agents are effective for pyelonephritis. Avoid in pregnancy and children. Moxifloxacin is not listed due to lack of indication and efficacy data. 

TABLE 76-3. Overview of Outpatient Antimicrobial Therapy for Lower Tract UTIs and Acute Pyelonephritis... 

It is known that an association exists between maternal UTI during pregnancy and fetal death, mental retardation, and developmental delay.24 Because of this known association, and because up to 7% of pregnant women have an asymptomatic bacteriuria that may progress to pyelonephritis, screening is necessary. In patients with significant bacteriuria, whether symptomatic or asymptomatic, treatment is recommended to avoid the complications discussed above. In the majority... 

Warren JW, Abrutyn E, Hebei JR, et al. Guidelines for antimicrobial treatment of uncomplicated acute bacterial cystitis and acute pyelonephritis. Clin Infect Dis 1999 29 745-758. 

A 30-year-old type I diabetic with renal complications develops acute pyelonephritis F aeruginosa is found in urine cultures and blood cultures. Combined therapy is instituted with an aminoglycoside and which of the following ... 

Secondary hypertension is much more common in children than in adults. Kidney disease (e.g., pyelonephritis, glomerulonephritis) is the most common cause of secondary hypertension in children. Coarctation of the aorta can also produce secondary hypertension. Medical or surgical management of the underlying disorder usually restores normal BP. 

The principal infecting organism is Escherichia coli, but Proteus mirabilis and Klebsiella pneumoniae account for some infections. Untreated bacteri-uria may result in pyelonephritis, preterm labor, preeclampsia, transient renal failure, and low birth weight. 

Treatment of asymptomatic bacteriuria is necessary to reduce the risk of pyelonephritis and premature delivery. A course of 7 to 10 days of treatment is common. A repeat culture 10 days after completion of treatment is recommended. 

Serious infection (endocarditis, meningitis, pyelonephritis with bacteremia)... 

Infections of the urinary tract represent a wide variety of clinical syndromes, including urethritis, cystitis, prostatitis, and pyelonephritis. 

Lower tract infections include cystitis (bladder), urethritis (urethra), prostatitis (prostate gland), and epididymitis. Upper tract infections (such as pyelonephritis) involve the kidney and are referred to as pyelonephritis. 

An important virulence factor of bacteria is their ability to adhere to urinary epithelial cells by fimbriae, resulting in colonization of the urinary tract, bladder infections, and pyelonephritis. Other virulence factors include hemolysin, a cytotoxic protein produced by bacteria that lyses a wide range of cells... 

Pregnancy Acute pyelonephritis As above 1. Amoxicillin-davulanate x 7 days 2. Cephalosporin x 7 days 3. Trimethoprim-sulfamethoxazole x 7 days Avoid trimethoprim-sulfamethoxazole during third trimester... 

Glomerulonephritis, pyelonephritis, renal infarction, papillary necrosis, renal tumors, kidney stones Pyelonephritis, interstitial nephritis... 

Pyelonephritis, interstitial nephritis Glomerulonephritis, renal infard, lupus nephritis, vasculitis... 

Chronic exposure of both rats and mice resulted in tubular nephropathy in both males and females. In rats, lesions were present in 45-66% of the males when they were sacrificed at 110 weeks after receiving 212 and 423 mg/kg/day hexachloroethane for 66 weeks of a 78-week exposure period (NTP 1977 Weisburger 1977). The renal lesions were characterized by hyperchromic regenerative epithelium, necrosis, interstitial nephritis, fibrosis, focal pyelonephritis, tubular ectasis, and hyaline casts. Lesions were also present in females but had a lower incidence (18% and 59%) for the two dose groups. Two-year exposures of male rats to much lower doses (10 and 20 mg/kg/day) resulted in similar effects on the kidneys (NTP 1989). Minimal to mild nephropathy was present in females for doses of 80 and 160 mg/kg/day. Over 90% of the male and female mice exposed to 590 and 1,179 mg/kg/day hexachloroethane for 78 weeks displayed tubular nephropathy when sacrificed at 90 weeks (NTP 1977 Weisburger 1977). Regenerative tubular epithelium was visible and degeneration of the tubular epithelium occurred at the junction of the cortex and the medulla. Hyaline casts were present in the tubules, and fibrosis, calcium deposition, and inflammatory cells were noted in the kidney tissues. 

Lane, M. C., and Mobley, H. L. T. (2007). Role of P-fimbrial-mediated adherence in pyelonephritis and persistence of uropathogenic Escherichia coli (UPEC) in the mammalian kidney. Kidney Int. 72,19-25. 

Otto, G., Sandberg, T., Marklund, B.-L, Ulleryd, P., and Svanborg, C. (1993). Virulence factors and pap genotjqjes in Escherichia coli isolates from women with acute pyelonephritis, with or without bacteremia. Clin. Infect. Dis. 1993, 448-456. 

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