What Is Acute Pyelonephritis?

Acute pyelonephritis refers to acute infectious diseases of the renal pelvis mucosa and renal parenchyma, mainly caused by E. coli, and also caused by Proteus, Staphylococcus, Streptococcus faecalis and Pseudomonas aeruginosa. The most serious complication of acute pyelonephritis is toxic shock.

Basic Information

Visiting department: Nephrology, Urology
Multiple groups: Women of childbearing age
Common locations: kidney

Common causes: Mainly caused by E. coli infection
Common symptoms: Chills, fever, nausea, vomiting, dysuria, frequent urination, urgency, etc.

Causes of Acute Pyelonephritis

There are two ways of infection: Ascending infection, bacteria enter the renal pelvis from the ureter, and then invade the renal parenchyma. 70% of acute pyelonephritis originates from this route. Hematogenous infection. Bacteria enter the renal tubules from the bloodstream and invade the renal pelvis from the renal tubules, accounting for about 30%. Most are staphylococcal infections. Urinary tract obstruction and stagnation of urinary flow are the most common causes of acute pyelonephritis. Simple pyelonephritis is rare.

Clinical manifestations of acute pyelonephritis

Typical acute onset of acute pyelonephritis, clinical manifestations are episodic chills, fever, back pain (significant throbbing pain at the rib and spine corners), and usually accompanied by abdominal cramps, nausea, vomiting, dysuria, Frequent urination and nocturia, the disease can occur at various ages, but most common in women of childbearing age, mainly with the following symptoms.

General symptoms

High fever, chills, body temperature mostly between 38 ~ 39 , but also up to 40 , different heat types, generally relaxation type, can also be intermittent or retentive type, with headache, systemic soreness, may have large heat regression Khan and so on.

2. Urinary symptoms

Patients have low back pain, mostly dull or sore, of varying degrees, and a few have abdominal cramps, which radiate along the ureter toward the bladder; at the time of physical examination, at the point of the upper ureter (the intersection of the outer rectus abdomen and the flat line of the umbilicus) or rib waist There is tenderness at the point (the intersection of the outer edge of the psoas major muscle and the twelve ribs), and positive pain in the kidney area. Patients often have urinary bladder irritation symptoms such as frequent urination, urgency, and dysuria. In ascending infections, they can precede systemic symptoms. .

3. Gastrointestinal symptoms

May have loss of appetite, nausea, vomiting, and individual patients may have mid-upper or total abdominal pain.

4. Bacteremia and sepsis

Patients with symptomatic acute pyelonephritis can be complicated by bacteremia during the course of their disease.

5. Shock and disseminated intravascular coagulation (DIC)

6. Pediatric patients

Children's urinary symptoms are usually not obvious. In addition to systemic symptoms such as high fever, onset of seizures, convulsions, and fever, vomiting, nonspecific abdominal discomfort or poor movement in children under 2 years of age.

Acute pyelonephritis

Routine urine test

(1) When the pyelonephritis is observed with the naked eye , urine color may be clear or cloudy, and there may be a rotten smell. Very few patients show gross hematuria.

(2) 40% to 60% of patients have microscopic hematuria. Most patients have 2-10 red blood cells per HPF (high-power field of view). A few see a large amount of red blood cells under the microscope. Leukocyte urine (ie pyuria) is common. Urine sediment after centrifugation Microscope> 5 / HPF, often showing white blood cells in the acute phase, if the white blood cell cast is seen, it provides an important basis for the diagnosis of pyelonephritis. At present, domestic blood cell counting disks are used to check clean and uncentrifuged urine, with 8 / mm ³ was pyuria.

(3) Urinary protein content The qualitative examination of urinary protein in pyelonephritis is trace- +. The quantitative examination is about 1.0 g / 24 hours, and generally does not exceed 2.0 g / 24 hours.

2. Quantitative culture of urine bacteria

Quantitative culture of urinary bacteria is an important indicator for determining the presence or absence of urinary tract infections. As long as conditions permit, mid-range urine should be used for quantitative bacterial culture.

3. Urine smear microscopy method

Microbiological examination of urine smear without centrifugation. Urine sediment smear microscopy for bacterial method.

4. Urine chemical examination

This method is simple and easy, but has a low positive rate and limited value, and cannot replace the quantitative culture of urine bacteria.

5. Urinary leukocyte excretion rate

Urinary leukocyte excretion rate is a more accurate method for measuring leukocyte urine.

6. Blood test

Leukocyte counts and neutrophils can be increased in the acute phase, and red blood cell counts and hemoglobin can be slightly reduced in the chronic phase.

7. Serology

There are several clinically significant methods: Immunofluorescence technology to check antibody-encapsulated bacteria (ACB). Identification of serotypes of urinary bacteria. Determination of Tatom-Horsefall (TH) protein and antibody. urine 2 microglobulin (2-MG) measurement.

8. Renal function test

Acute pyelonephritis occasionally has urinary concentrating dysfunction, which can be recovered after treatment. Chronic pyelonephritis can have persistent renal dysfunction: Renal concentrating dysfunction, such as increased nocturia, and decreased morning urine permeability. Renal acidification is reduced, such as increased morning urine pH, increased urine HCO ₃ ^-and decreased urine NH ₄ . glomerular filtration dysfunction, such as reduced endogenous creatinine clearance, blood urea nitrogen, increased creatinine and so on.

9.X-ray inspection

Abdominal plain film can be due to the abscess around the kidney and the shape of the kidney is unclear. Venous urography can find delayed development of renal calamity and weakened renal pelvis. It can show urinary tract obstruction, renal or ureteral deformity, stones, foreign bodies, tumors and other primary lesions.

10.CT and B-ultrasound

(1) CT examination shows that the shape of the affected kidney is swollen, and a wedge-shaped reinforced reduction area is visible, which radiates from the collective system to the renal capsule. The lesion can be single or multiple.

(2) B-ultrasound showed that the level of renal cortex medullary is unclear, and there are areas lower than the normal echo, and it can also determine whether there are obstructions, stones, etc.

Diagnosis of Acute Pyelonephritis

The diagnosis was confirmed based on the etiology, clinical manifestations and various examinations.

Acute pyelonephritis treatment

General treatment

Patients with acute pyelonephritis are accompanied by fever, significant urinary tract irritation symptoms, or bed rest when accompanied by hematuria. The body temperature returns to normal, and the symptoms can be raised after the symptoms are significantly reduced. It usually rests for 7 to 10 days, and can return to work after the symptoms completely disappear. Those with obvious fever and systemic symptoms should be given a liquid or semi-liquid diet according to the patient's general condition. After no obvious symptoms, change to a normal daily diet. Those with high fever and obvious digestive tract symptoms can be rehydrated intravenously. Drink plenty of water every day, drink more water and urinate more, flush the urinary tract, promote the discharge of bacteria and inflammatory secretions, and reduce the hypertonicity of renal medulla and nipples, which is not conducive to the growth and reproduction of bacteria.

2. Antimicrobial treatment

Treatment options should be based on the severity of the patient's symptoms and signs. Before the urine sample is obtained for quantitative bacterial culture and drug sensitivity report is obtained, the treatment plan should be decided based on the experience of the doctor. In view of the fact that pyelonephritis is caused by gram-negative bacteria, effective antibiotics for gram-negative bacteria are generally preferred, but care should be taken to treat gram-positive bacteria infection.