Renal Disorders 1 – Obstruction, Stones, ATN & UTIs

Vocabulary flashcards covering obstructive uropathy, kidney stones, acute tubular necrosis and urinary tract infections from the lecture notes.

Obstructive uropathy

Structural or functional blockage anywhere in the urinary tract that impedes urine flow, dilates the tract, raises infection risk and compromises renal function.

Hydroureter

Dilation of the ureter produced by accumulation of urine above an obstruction.

Hydronephrosis

Enlargement of the renal pelvis and calyces caused by backed-up urine pressure.

Upper urinary tract obstruction

Blockage affecting kidney or ureter, commonly from renal calculi or tumour compression.

Lower urinary tract obstruction

Obstruction involving bladder storage or emptying, often due to neurogenic bladder or prostate enlargement.

Neurogenic bladder

Bladder dysfunction from neurological disorders (e.g., stroke) leading to impaired storage/voiding.

Benign prostatic hypertrophy (BPH)

Non-malignant enlargement of the prostate that can obstruct urine outflow in men.

Flank pain

Sharp pain in the side between ribs and hip, characteristic of obstruction or kidney stones.

Renal calculi (kidney stones)

Small hard mineral deposits that form inside the kidney.

Calcium stones

Most common stones; excess calcium combines with oxalate or phosphate—typical in middle-aged men with family history.

Struvite stones

Magnesium ammonium phosphate stones linked to infections by urease-producing bacteria (e.g., Proteus).

Uric acid stones

Stones forming in highly acidic urine; associated with gout, leukaemia, ulcerative colitis.

Renal colic

Sudden severe flank pain (often radiating to groin) due to ureteric stone movement.

Acute Tubular Necrosis (ATN)

Reversible death of tubular epithelial cells causing acute kidney injury.

Ischaemic ATN

ATN produced by reduced renal blood flow/oxygen (trauma, pancreatitis, renal artery stenosis, emboli).

Nephrotoxic ATN

ATN caused by toxic agents (e.g., gentamicin, contrast dye, heavy metals, organic solvents).

Initiation phase (ATN)

Early period of tubular injury with falling GFR, hypoperfusion, rising serum creatinine & BUN.

Maintenance phase (ATN)

Established injury; sustained low GFR, continued rise in urea/creatinine, azotaemia and fluid retention.

Recovery phase (ATN)

Repair stage; surviving tubular cells proliferate, urine output increases, serum waste levels fall.

Azotaemia

Elevation of nitrogenous wastes (urea, creatinine) in blood due to impaired renal excretion.

Urinary tract infection (UTI)

Inflammation of urinary epithelium, most often from gut bacteria such as E. coli.

Ascending infection

UTI pathway where microbes enter via urethra and move up to bladder, ureter and kidney.

Haematogenous UTI

Kidney infection that reaches the organ via the bloodstream (≈10 % of cases).

Antibacterial properties of urine

Low pH, high urea and high osmolality that inhibit bacterial growth.

Cystitis

Inflammation of the bladder; the most frequent site of UTI.

Haemorrhagic cystitis

Type of cystitis characterised by bleeding from bladder mucosa.

Suppurative cystitis

Cystitis in which pus forms on the bladder epithelium.

Acute pyelonephritis

Infection of the renal pelvis and interstitium (usually E. coli) often precipitated by vesicoureteric reflux.

Chronic pyelonephritis

Persistent/recurrent kidney infection causing tubule destruction, scarring and possible progression to renal failure.

Risk factors for UTI in females

Short urethra, proximity of anus, absence of prostatic antibacterial secretions; peak incidence ages 15-40.

Pregnancy-related UTI risk

Progesterone relaxes smooth muscle and slows urine flow; fetal pressure adds obstruction, increasing infection risk.

Risk factors for UTI in males > 50 yrs

Prostate enlargement leads to urinary stasis and higher infection rates.

Catheter-associated UTI

Infection facilitated by an indwelling urinary catheter disrupting normal urinary defences.