Kidney Infection

Kidney infection is also referred to as the pyelonephritis. It is an unpleasant and dangerous situation where the kidney tissue is attacked by a bacterial infection. The infection can affect not only the kidney, but also the bloodstream where it can cause a septic condition.


Pyelonephritis is typically caused by bacteria. The bacteria can get into the kidney either from the lower parts of the urinary tract (i.e. urinary tract infections), or from the bloodstream (i.e. by sepsis).


Increased risk of pyelonephritis is in patients with impaired outflow of urine. When the urine does not flow correctly and accumulates, it is an ideal environment for bacterial presence and multiplication. Repeated pyelonephritis occurs in children with vesicoureteral reflux. This congenital condition is caused by frequent reflux of urine from the bladder back into the ureters and kidneys. Pyelonephritis (and urinary tract infections in general) is typical for patients with weakened immunity (such as chronic diabetics).


The classic symptoms include fever, malaise, fatigue, nausea and sometimes vomiting. The fever may be very high and it is frequently accompanied with chills and strong headache that may mimic meningitis. The patient also experiences painful burning sensations during urination and blood in urine can occur as well. Due to the anatomical location of kidneys, their infection causes back pain the lumbar area on the side of infection. The pain worsens when the area is tapped. When the infection spreads from a kidney into the bloodstream, it leads to sepsis. When untreated, the sepsis can easily progress in to a circulatory shock.


Clinical findings should be accompanied with blood tests that can confirm presence of inflammation in the organism (elevated CRP and high white blood cell count). The basic urinalysis shows presence ob bacteria and leukocytes in the urine. Microbiological examination may find a particular bacterial type and evaluate its sensitivity to antibiotics. It is advisable to examine the kidney by an ultrasound, which can rule out cases of urine accumulation.


Primary method of treatment is the administration of antibiotics and adequate hydration. Supportive medications include non-steroidal anti-inflammatory drugs and other painkillers. When there is present any disorder of urine flow, it must be urgently solved as the urine outflow must be maintained at all cost.


Jiri Stefanek, MD  Author of texts: Jiri Stefanek, MD
 Sources: basic text sources