KIDNEY INFECTIONS

Aetiology

Renal infections arise in the following ways:

Haematogenous infection from primary site in the tonsils or carious teeth or from cutaneous infections, particularly boils or carbuncle.

Renal tuberculosis occurs by blood borne spread from lymph nodes in the neck, chest or abdomen.

Ascending infection in the urinary tract is the most common route, and it is most likely to occur when there is vesicoureteric reflux. Urinary stasis and the presence of calculi are common contributory factors.

Kidney infections are:

*Acute pyelonephritis:

      In childhood

      In pregnancy

      With urinary obstruction

*Chronic pyelonephritis:

      Reflux nephropathy

*Pyonephrosis

*Renal abscess

*Perinephric abscess

Bacteria

Escherichia coli and other Gram-regative organisms are commonly responsible. When Streptococcusfaecalis is present it is usually accompanied by other organisms.

In E. coli and Streptococcal infections the urine is acidic.

Proteus spp. and Staphylococci split urea to form ammonia, which makes the urine alkaline and promotes the formation of calculi.