Pyelonephritis is an ascending urinary tract infection that has reached the renal pelvis of the kidney. If the infection is severe, the term "urosepsis" is used. It requires antibiotics as therapy, and treatment of any underlying causes to prevent recurrence.It presents with dysuria , abdominal pain and tenderness of the bladder area and the side of the involved kidney (renal angle tenderness) which may be elicited by performing the kidney punch. In many cases there are systemic symptoms in the form of fever, rigors, headache, and vomiting. In severe cases, delirium may be present.
- Mechanical: any structural abnormalities to the kidneys and the urinary tract, vesicoureteral reflux (VUR) especially in young children, calculi , urinary tract catheterisation, nephrostomy, pregnancy, neurogenic bladder (e.g. due to spinal cord damage, spina bifida or multiple sclerosis) and prostate disease (e.g. benign prostatic hyperplasia) in men
- Constitutional:diabetes mellitus, immunocompromised states
Most cases of community-acquired pyelonephritis are due to bowel organisms that enter the urinary tract. Common organisms are E. coli (70-80%) and Enterococcus faecalis. Hospital-acquired infections may be due to coliforms and enterococci.
The presence of nitrite and leukocytes on a urine dipstick test in patients with typical symptoms are sufficient for the diagnosis of pyelonephritis.In patients with recurrent ascending urinary tract infections, it may be necessary to exclude an anatomical abnormality, such as vesicoureteral reflux or polycystic kidney disease. Investigations that are commonly used in this setting are ultrasound of the kidneys or voiding cystourethrography.