Pyonephrosis is defined as obstruction and infection of the kidney resulting in pus formation. A kidney stone is the usual cause of obstruction, and the kidney becomes distended by pus and destroyed by inflammation.
The common causes include
1. Infected Hydronephrosis
4. Hydronephrosis is obstruction to the free flow of urine, which is produced in the kidney. Once there is obstruction there is potential for infection, as the urine will be stagnant. Common causes of obstruction are stones, strictures, tumor, nerogenic bladder, duplicate kidneys with obstuctuve component, etc
5. There are several organisms like E.coli, Proteus, Psuedomonas, Staphylococcus etc, which causes this bacterial infection. Many a time it is a combination of organisms, which also causes the infection.
6. Certain other diseases such as diabetes, anemia, other conditions with steroids will increase the infection, leading to rapid progression.
One or combination of these symptoms are observed
1. Pain in the flanks
2. High fever, which can be intermittent
3. Severe chills and Rigors
4. Vomiting and giddiness
5. Feeling exhausted, weak and sick.
6. Pus in the urine
7. Swelling in the flanks
8. Feeling of uneasiness in the stomach
Enter the number of blood cells with a manual differential, chemistry with serum BUN and creatinine, urinalysis with culture and blood cultures are indicated in the first diagnose for a patient with suspected pyonephrosis.
Addition of a C-reactive protein study will help with the diagnosis of the infected hydronephrotic kidney.
A urine culture of the fluid above the obstruction is obtained in order to guide antibiotic therapy.
A culture specimen is obtained from an open-ended catheter that has been advanced above the obstruction during stent placement.
Cultures can also be obtained from the tube through the skin at the time of nephrostomy placement if they were chosen for this course of action.
Routine radiographic imaging of patients with uncomplicated urinary tract infections is not generally used.
Ultrasonography:The sensitivity of renal ultrasonography is to differentiate hydronephrosis from pyonephrosis. Ultrasonographic findings are suggestive of pyonephrosis include the presence of hydronephrosis in conjunction with debris in the collecting system. The presence of debris and layering of low-amplitude echoes in the hydronephrotic kidney will indicate pyonephrosis.
CT scaning is extremely halpfull in diagnosing pyonephrosis
MRI -magnetek resonance imaging.
1. Initially, treat patients with appropriate intravenous antibiotics consisting of aminoglycoside (gentamicin) and gram-positive coverage (ampicillin) prior to surgery.
2. Surgical Therapy:With the advent of ultrasonography and CT scanning, then percutaneous drainage is the main stay of treatment.
3. CT- and ultrasound-guided drainage will significantly decrease the need for nephrectomy, resulting in renal preservation.
4. Retrograde decompression of pyonephrosis in patients who are seriously ill, are not recommended because of the need for internal instrumentation and the possible future need for antegrade irrigation.
This avoids placement of percutaneous nephrostomy tube and allows internalization of drainage catheter, but it does not allow for the diversion of medicines or treatment of progressive blockage as there is a need in some cases with funguria and infected stones.
Consider treating patients with pyonephrosis.
5. Decompression and drainage: To perform retrograde stent placement.
6. 1.The rear cup should be introduced with an oblique posterolateral approach in the back of the axillary line, 2-4 cm below the 12th rib.
7. The tract is then dilated by using the Seldinger technique, and an 8F-14F nephrostomy tube is placed and connected to closed-system drainage bag. The infectious process often resolves within 24-48 hours following drainage, and patient will improve significantly.
Outcome and Prognosis of Most infectious processes will resolve within 24-48 hours and significantly improve after nephrostomy or retrograde stent drainage of the infection.
Long-term complications are rare and are managed promptly, but injury to the functional renal unit, abscesses, fistulas, and scarring will occur when definitive therapy is delayed.
Antegrade percutaneous nephrostomy placement will allow both drainage of pus and antegrade infusion of antifungal and antibiotic drugs properly treat these infections.
Non-response to therapy and disease progression after percutaneous drainage are the indications for nephrectomy, but current technology reflects that preserving the maximal number of renal units is prudent.