Pyelonephritis Symptoms: Signs of Kidney Inflammation

Pyelonephritis is an infectious inflammation of the kidneys that often begins as a lower urinary tract infection. Below are the signs of the acute and chronic process, the localization of pain is discussed, and it is explained why the disease sometimes occurs without an increase in temperature.

What is pyelonephritis

Pyelonephritis is a nonspecific inflammatory process of bacterial etiology with predominant involvement of the tubular system of the kidney, renal pelvis, calyces, and parenchyma, mainly the interstitial tissue. By course, acute, chronic, and chronic with exacerbation variants are distinguished. It is the most common kidney disease in all age groups: at autopsies it is found in 8–20% of cases.

Among the causative agents, Escherichia coli, Proteus, enterococci, and Pseudomonas aeruginosa predominate. Infection most often enters through the blood from another focus of inflammation, less often by the ascending route from the urethra and bladder. The risk is higher with kidney stones, weakened immunity, diabetes, the presence of a catheter, and spinal cord injury. The acute process occurs as serous in 64% of cases and as purulent in 36%.

Main symptoms of acute pyelonephritis

Symptoms of pyelonephritis may include:

• high body temperature, chills, feeling hot or cold;
• pain in the lower back or in the side;
• nausea, vomiting, diarrhea, muscle aches, and flu-like symptoms;
• pain, burning, or stinging during urination;
• frequent and urgent urges, dark or cloudy urine.

The list is supplemented by fatigue, pressure in the lower abdomen, and an unpleasant odor of urine, sometimes with a reddish tint. In children the picture is different: urinary incontinence and drowsiness are possible, and in a child under two years of age the only sign may be high temperature. Urinary tract infections overall rank second in frequency among all infections of the body.

Where it hurts in pyelonephritis

Pain is possible in the lower back or in the side, below the ribs; sometimes pressure is felt in the lower abdomen.

Symptoms of pyelonephritis in women and in men

Differences in symptoms by sex have not been described; the frequency differs: girls and women of young and middle age are affected 6 times more often than boys and men, and urinary tract infections occur approximately 4 times more often in women than in men. In pregnant women, kidney inflammation is classified as a condition requiring urgent medical consultation.

Pyelonephritis without fever: does it happen

Among the variants of the course of chronic pyelonephritis, latent, asymptomatic, and remission-stage variants are distinguished. In a child under 2 years of age, the only sign may be high temperature. To confirm the diagnosis, a urine test is needed.

When a doctor is needed if pyelonephritis is suspected

The diagnosis is confirmed by a urine test; in a hospital setting, blood parameters are additionally monitored. Reasons for urgently consulting a doctor include very high temperature or chills, temperature below 36 °C, pain in the lower abdomen or in the back under the ribs, blood in the urine, nausea and vomiting, absence of urination for 24 hours, and pregnancy.

Pyelonephritis by itself is not a reason to call an ambulance; 103/112 — if, against the background of signs of kidney inflammation, confusion, drowsiness, or difficulty speaking appear.

The material is for reference purposes and does not replace consultation with a doctor.

This content is for reference and does not replace a doctor's consultation. Medical disclaimer