In the case of chronic pyelonephritis, it is necessary to carefully evaluate the urinary tract through diagnostic investigations capable of highlighting any anomalies affecting the urinary tract (such as urography or cystography ) and possibly resort to surgical correction. In fact, in the presence of urinary tract obstruction, infections are often resistant to therapy and tend to recur. Several surgical procedures can be performed to correct these conditions; based on the anomaly, the doctor can opt for example for:
- Pyeloplasty , to repair the renal pelvis in case of obstruction of the ureteropelvic joint.
- Transurethral approach via cystoscopy to remove kidney stones and/or ” basketball ” procedure to recover small renal or ureteral mineral aggregations.
- Surgical correction of congenital anomalies leading to vesicoureteral reflux (example: reimplantation of ureters ).
Excluding the anatomical alteration, the treatment is aimed at eradicating the infection and correcting the causes that predispose to chronic pyelonephritis. If the cause is detectable in a urinary tract infection , it is possible to attempt to eradicate the responsible pathogen through initial antibiotic therapy and subsequent long-term maintenance therapy with low-dose disinfectants . It may be necessary to continue antibiotic therapy for prolonged periods of time, even for a few months (up to 3 to 6 months).
The follow-up of the treatment can be carried out by means of a urine culture performed one week after the end of the drug therapy, to demonstrate the elimination of the pathogen. In cases of flare-up of the disease, the therapy will be similar to that of acute pyelonephritis. Antibiotic therapy for relapses aims to reduce the number of acute episodes of infection, facilitating the healing process and stopping the progressive functional deterioration of the kidney. Other types of medical treatment include the prescription of drug therapy to control hypertension and kidney failure. In severe unilateral forms of chronic pyelonephritis, surgical removal of the diseased kidney ( nephrectomy) is indicated.).
If adequate treatment is administered quickly, the disease tends to arrest its progression towards renal failure and the expected results are generally quite good. Most individuals develop renal scarring and kidney atrophy. Antibiotic treatment for the infection and antihypertensive therapy for high blood pressure are usually effective. The outcome of various surgical procedures (pyeloplasty, stone removal and nephrectomy) is generally positive.
The complications of chronic pyelonephritis include recurrent infections from resistant bacteria and the possibility of incurring renal damage which progressively leads to the formation of scars, with reflux nephropathy, renal failure and secondary hypertension (high blood pressure which occurs following parenchymatous alterations or when the renal artery , or one of its branches, is stenotic). The evolution of chronic pyelonephritis can induce pyonephrosis (severe and extensive kidney disease characterized by the collection of pus, with destruction of the renal parenchyma), focal glomerulosclerosis ( nephrotic syndrome , caused by alterations of the renal glomeruli, with non-selective proteinuria , hypertension and microhematuria), urosepsis ( systemic inflammatory response propagating from the urinary tract), chronic renal failure , which, in the terminal phase, can even lead to the need for an organ transplant.
A rare and particular variant of the chronic form is xanthogranulomatous pyelonephritis , characterized by the formation of yellow-orange abscesses and granulomas in the medullary area , with severe renal destruction and a clinical picture that can resemble renal cell carcinoma or other inflammatory processes affecting the renal parenchyma. Most patients experience recurrent fever , urosepsis, anemia , pain , kidney stones, and loss of function of the affected kidney. Bacterial cultures of renal tissue are commonly positive. Usually, for xanthogranulomatous pyelonephritis a nephrectomy (removal of the kidney) is necessary for definitive treatment.
As with all other forms of chronic kidney disease, the patient should be monitored for progression of chronic pyelonephritis and for the development of conditions such as hyperlipidemia, hypertension, diabetes, and deterioration of renal function .