What is Secondary Acute Pyelonephritis?
It differs from the primary acute pyelonephritis in the clinical picture by the greater severity of local symptoms, which makes it faster and easier to recognize the disease. The most common causes of secondary acute pyelonephritis are kidney and ureteral stones, followed by abnormalities of the urinary tract, pregnancy, ureteral and urethral strictures, and prostatic adenoma glands, and in children – due to violations of urodynamics (complications in the postoperative period, vesicoureteral reflux, urolithiasis).
Symptoms of Secondary Acute Pyelonephritis
In the presence of a stone or other occlusive factor, attack of pyelonephritis is often preceded by a typical attack of renal colic. Urinary congestion and infection lead to a more pronounced clinical picture of acute pyelonephritis than during the primary inflammatory process in the kidney. The patient’s condition quickly deteriorates: the body temperature rises, which is maintained at 38–39 ° C, general weakness, weakness, headache, thirst, dry mouth increase, vomiting, euphoria, tachycardia appear.
The pain in the lumbar region is permanent and intense. An enlarged and painful kidney is palpated. Increases and becomes a “fiery” pain during palpation in the hypochondrium, Pasternatsky symptom is pronounced. There is a pronounced protective tension of the lumbar muscles and the muscles of the anterior abdominal wall. In children, secondary purulent pyelonephritis is manifested by symptoms of fever: the body temperature very quickly reaches high numbers, often remitting nature. A chill of tremendous character appears, often arising at the same hours of the day several times a day. Following the chill, the body temperature rises to 39 – 41 ° C, a sharp headache, then sweating with a drop in body temperature. Before the onset of subsequent chills, the child, especially the younger, is in a state of adynamia. In contrast, adults in children to the forefront in the clinical picture are common symptoms, rather than local, which may make diagnosis more difficult.
For newborns and infants, there is a sharp hyperpyrexia with indistinctly pronounced meningeal signs, thirst, and rapid weight loss. There is pain when urinating. When palpating the lumbar region, the children scream and try to move the doctor’s hand away.
Diagnosis of Secondary Acute Pyelonephritis
In the history pay attention to the former attacks of renal colic and discharge of calculi, urinary disorders, injuries, previous prostatitis, urethritis. Of the objective data, the most valuable for the diagnosis of secondary acute pyelonephritis are high, hectic nature of body temperature and especially stunning chills, as well as the local symptoms listed above in the area of the affected kidney.
Laboratory confirmation is important to confirm the diagnosis. Bacteriuria and leukocyturia are always expressed, except in cases of complete occlusion of the ureter of the affected kidney. The urine contains a large number of active leukocytes (50% or more) and Sternheimer-Malbin cells are found in most patients. Bacteriuria is more common than in primary acute pyelonephritis, caused by the bacteria of the Proteus group and Pseudomonas aeruginosa. Often there is proteinuria with a protein content of about 1 g / l. Immunochemical analysis of urine reveals the presence of proteins among uroproteins, the molecular weight of which does not exceed 200,000. The tubular type of proteinuria is combined with its selective nature. Urine testing should be carried out several times during the day, as it is not uncommon for children to have pyuria in all urine samples.
As a rule, there is a high blood leukocytosis and a shift of blood leukocyte formula to the left with neutrophilia due to an increase in stab neutrophils (up to 15–20%, and sometimes more) and with the advent of more youthful forms. ESR is always increased on average to 40–45 mm / hour. Blood toxicity is pronounced (an increase in the content of medium molecules and (3-4 microglobulin 3–4 times, the lifetime of paramecium in the blood is less than 20 minutes). For children with acute purulent pyelonephritis, anemia is characteristic due to the hemolytic effect of the infection and oppression of the hematopoietic system due to intoxication.
To establish the side of the disease with unilateral pyelonephritis or the greatest lesion in a bilateral process, the definition of comparative leukocytosis has diagnostic value. Count the number of leukocytes in the blood taken from the finger and both lumbar regions. Higher leukocytosis indicates the side of the disease.
The serum urea content is increased in approximately 25–30% of patients with severe secondary acute pyelonephritis, since many of them have a bilateral inflammatory process in the kidneys. In unilateral disease, an increase in the serum urea content may depend on urine resorption from the affected kidney due to renal reflux and toxic effects on the contralateral kidney.
Chromocytoscopy in patients with secondary acute pyelonephritis in some cases allows to establish the presence, extent and cause of impaired passage of urine from the kidney. It is possible to detect bullous edema of the mouth of the ureter with a stone in the intramural ureter or ureterotsel as a cause of violation of urine passage.
Radiological methods of research occupy the most important place in the diagnosis of secondary acute pyelonephritis. Survey radiography of the urinary system reveals additional shadows suspicious of stones in the kidney or ureter, as well as increased size of the affected kidney, blurred contour of the lumbar muscle and mild scoliosis of the spine towards the lesion. On the excretory urograms in patients with occlusion of the urinary tract, the shadow of the radiopaque substance in the affected kidney and along the ureter is either not detected at all, or (with partial obstruction) appears later, filling the ureter, pelvis and calyx expanded above. This is better defined in later urograms (after 40–50 minutes, 1.5 hours, and later). An ultrasound examination reveals an extension of the renal pelvis system, often with the presence of calculus in it.
Retrograde ureteropyelography should be performed only under strict indications. It is necessary for X-ray negative stones or other causes of violation of the passage of urine, which can not be clearly established without this study, and at the same time, it is urgent to resolve the issue of surgical intervention. At the same time, catheterization of the ureter can have simultaneously therapeutic value.
Since the main factor in the development of acute secondary pyelonephritis is urinary obstruction, the early clinical symptom is pain in the affected kidney, often such as renal colic. This circumstance facilitates the differential diagnosis of acute secondary pyelonephritis with common infectious diseases, acute appendicitis and acute cholecystitis. Palpable kidney, a positive symptom of Pasternack, dysuria, bacteriuria, leukocyturia, a large number of active leukocytes in the urine, reduced or no kidney function on the side of the disease indicate in favor of acute secondary pyelonephritis.
If it is caused by a stone in the lower third of the ureter, then in some cases differential diagnosis is necessary with acute inflammation of the uterus. Abdominal pain, accompanied by symptoms of irritation of the pelvic peritoneum, enlarged and painful appendages of the uterus during vaginal examination, the absence of leukocyturia and bacteriuria, undisturbed passage of urine can diagnose acute adnexitis. A great help in the differential diagnosis is rendered by ultrasound of the kidneys, excretory urography and chromocytoscopy, which reveal a violation of urine outflow in secondary acute pyelonephritis.
Treatment of Secondary Acute Pyelonephritis
In case of secondary acute pyelonephritis, treatment should begin with the restoration of the passage of urine from the kidney, which is fundamental. In acute pyelonephritis caused by occlusion of the ureter with a small stone, which gives hope for its independent discharge in the future, and in early terms (from 1 to 3 days) from the onset of an acute inflammatory process in the kidney, an attempt to restore the outflow of urine can be made using ureteral catheterization. If you manage to hold the catheter past the stone in the pelvis, the evacuation of its contents leads to a rapid relief of pyelonephritis attack.
If catheterization of the pelvis for one reason or another (most often due to an insurmountable obstacle at the location in the ureter of the stone) fails, and drug therapy does not eliminate the attack of pyelonephritis during the first 3 days, then an emergency surgery is performed – ureterolithotomy, or drainage of the kidney by a low-traumatic percutaneous puncture method under ultrasound control (percutaneous puncture nephrostomy).
When occlusion of the pelvic-ureteric segment or ureter by a stone, the dimensions of which do not allow us to hope for its rapid independent discharge, surgical treatment is immediately applied. In the process of preparing the patient for surgery to reduce the degree of purulent intoxication, as a temporary measure, the catheterization of the ureter or renal pelvis is acceptable. According to indications, taking into account the age of the patient and his condition, especially in children, in conditions of a significantly dilated cup-pelvis-plating system, it is advisable to resort to percutaneous nephrostomy, which allows obtaining an adequate flow of urine from the pelvis.
The use of a self-retaining ureteral catheter (stent) allows not only to stop the attack of pyelonephritis, but also to produce extracorporeal crushing of the stone in the renal pelvis with the energy of a shock blast wave. In addition, the stone can be removed from the kidney using percutaneous puncture nephrostomy (mechanically, with a special tool), or crushed in the pelvis by shock waves (through the percutaneous nephrostoma). This catheter (stent) provides free flow of urine from the kidney after crushing the stone, eliminates ureteral occlusion with calculus fragments, and helps prevent acute secondary pyelonephritis.
The ureteral catheter provides urine outflow from the renal pelvis, and against this background, targeted intensive antibacterial therapy leads to an improvement in the patient’s condition, a decrease in body temperature to normal numbers, the disappearance of chills, a reduction in pain in the kidney area, and a decrease in blood leukocytosis. The attack of acute secondary pyelonephritis is cured. However, the urine of patients always contains a large amount of mucopurulent flakes that can occlude the lumen of the ureteral catheter and again disrupt the passage of urine. This, as a rule, leads to a new exacerbation of the inflammatory process in the kidney and is an indication for surgery.
With secondary acute pyelonephritis in the early stage of the disease (2-3 days), when it is assumed that there is a serous or minor purulent inflammatory process in the kidney, it can be limited to removing the stone from the pelvis or ureter without draining the renal pelvis. In the later stages of the disease (4–6 days), when a purulent-necrotic process has already appeared in the kidney, the removal of the kidney stone or ureter must be accompanied by the obligatory drainage of the renal pelvis by pyelonephrosis or simultaneous decapsulation of the kidney.
At an even later date, the purulent-inflammatory process in the kidney with signs of severe intoxication of the body, the main goal of surgery is to drain and decapsulate the kidney, and eliminating the cause of secondary acute pyelonephritis (for example, removing ureteral stone) is permissible only if it is not complicates the operation and does not aggravate the patient’s condition. In case of multiple carbuncles of the kidney, purulent fusion of its parenchyma, pyonephrosis and good function of the contralateral kidney, nephrectomy is used.
Conservative treatment with acute pyelonephritis in the presence of urinary tract occlusion is not successful, despite the use of the most powerful antibiotics and chemical antibacterial drugs. Conversely, the timely elimination of obstacles to the outflow of urine or the independent discharge of a small stone in the ureter leads to the rapid relief of the attack of acute pyelonephritis. In this regard, the main task of treating patients with acute secondary pyelonephritis is the rapid recovery of urine outflow.