Lecture 5 Tubular and Interstitial Disorders of the Kidney
How do you separate it from a lower UTI? Very easily. Pyelonephritis is seen more in women
b/c of their short urethra. Acute pyelonephritis is a systemic infection and is an infection of
the kidney proper. How does it get into the kidney? At the uretovesicular junc, the muscle
squeezes so there is no reflux of urine from the bladder into the ureter. This is true in normal
people. However, not all people have a normal vesicoureteral junction. So, what happens in a
pt with a bladder infection and the junction is incompetent, it leads to vesicouretal reflux, and
the infected urine refluxes up into ureters, and leads to ascending infection that goes all the way
up to the kidneys. So, they will ask you, “what is the mech of ALL UTI’s?” (urethritis, cystitis,
pelvitis, or pyelonephritis) – due to ascending infection from the beginning of the urethra.
Every woman (has nothing to do with cleanliness) has the same E coli serotype in her stool at
the introutus of the urethra and her vagina. So, with trauma or certain serotypes of E coli, it can
ascend up the urethra into the bladder. If the pt has an incompetent uretovesicular junc, up the
ureters into the kidneys. So, all UTI’s are ascending from the beginning of the urethra on up.
With acute cholecystitis, have painful urination (dysuria), increased frequency, suprapubic
pain, NO fever, no flank pain, NO WBC casts (with neutrophils in them) – why? B/c the WBC
casts develop in the renal tubules; they do not develop in the ureter or the bladder; they
develop in the kidney in the tubule.
So, fever, flank pain, and WBC casts = ACUTE PYELONEPHRITIS. So, its an ascending infection
due to incompetent vesicouretal junc. This usually shows up in newborn girls (and will be a
prob for rest of lives).
Example: kidney with white spots = abscesses seen in pyelonephritis. If you have constant acute
attacks of pyelonephritis, can become chronic. Therefore have increased risk of HTN and renal
Example: scarred kidney (on cortex), blunting of the calyces (occurs under the scar), seen on
intravenous pyelograms – dx? CHRONIC pyelonephritis. So, blunting of the calyces = CHRONIC
Acute Drug-induced interstitial nephritis
Can drugs produce a nephritis involving the interstitium and tubules? Yes – can be acute and
chronic and ez to diagnose. Why? B/c will have fever, and develop a rash. Fever + Rash
(obviously due to drug, b/c started after taking the drug), oliguria, eosinophiliuria (eosinophils