8 - Tubulointesterstitial Flashcards
The term tubulointerstitial?
Used to broadly refer to kidney disease that involves structures in the kidney other than the glomerulus
I.e. tubulointerstitial = kidney disease not glomerulus
Types of tubulinterstitial disease?
ATN - acute tubular nephritis
AIN - acute interstitial nephritis
Chronic disease - insult from acute factor or progressive insult w/o any obvious acute cause
S/s of renal tubule damage?
Generalized disruption of
- renal electrolyte handling,
- water balance
- PH maintenance
Polyuria?
Inability to concentrate urine
Hypovolemia (urine)
Salt wasting due to impaired reabsorption by damaged tubules
Lab findings for renal tubule damage?
Serum
- H BUN
- H creatinine
- Hyperkalemia (>5.0)
- Metabolic acidosis (renal tubular acidosis)
UA
- microscopic hematuria
- pyuria
- altered spec grav
- broad waxy casts
- high U(na) - (sodium wasting)
- glycosuria/phosphaturia
- proteinuria (<2 g/day)
What is isothenuria?
Kidney cannot formurine w a higher or lower spec grav than that of protein free plasma
Urine spec grav = protein-free plasma
How to treat renal tubular disease?
Manage the specific pathology/cause
- relief of obstruction
- surgery
- withdrawl of analgesics
- chelation therapy
Chronic tubulointerstitial disease diagnostic findings?
- Small kidney
- L concentrating ability
- Hyperchloremic metabolic acidosis
- L GFR
Four main causes of chronic tubulointerstitial disease?
HOVA
HOVA
H - heavy metals
O - obstructive uropathy
V - vesicoureteral reflux
A - analgesics
Definitive diagnosis of chronic tubulointerstitial disease?
Renal biopsy
MC cause of chronic tubulointerstitial disease?
Obstructive uropathy
Obstruction -> stasis -> infection -> renal failure
Maj causes of obstructive uropathy?
Prostate Uteral calculi Carcinoma Tumor Fibrosis
Long term obstruction can lead to?
Hydronephrosis
distention of:
- renal pelvis
- calicies
Pic on 17
Obstructive uropathy tx?
2 referrals
- Urology - relieve obstruction
- Nephrology - management
Who gets vesicoureteral reflux?
D/o of childhood
- young males w freq UTIs
What causes vesicoureteral reflux?
Retrograde urine flow from bladder -> kidneys during voiding
B/c incompetent vesicoureteral sphincter
Prognosis/severity of vesicoureteral reflux?
5 grades
Grades I-II resolve by age 5
(The rest arent mentioned so i guess we dont care)
What is the concern with vesicoureteral reflux?
Chronic UTI’s lead to permanent scarring and narrowing of ureters
Diagnosis for vesicoureteral reflux?
VCUG - voiding cystourethrogram
Tx for vesicoureteral reflux?
Abx
Urology referral
Surgery (maybe)
What is analgesic nephropathy?
Large qtys of analgesics
- 1g/day x 3 yrs
What is the typical culprit for analgesic nephropathy? Why?
NSAIDS - inhibition of renal prostaglandin synthesis
Leads to chronic lack of blood and ischemic damage
Pathologic findings of analgesic nephropathy?
- Tubulointerstitial inflammation
- Papillary necrosis
Labs for analgesic nephropathy?
UA
- sloughed papillae
- sterile pyuria
- hematuria
- mild proteinuria
- polyuria (tubular damage)
CBC
- anemia (GI bleeding)
Hyperkalemia
Radiographs of analgesic nephropathy?
Non-contrast CT
- bilateral small kidneys
- bumpy/irregular contours
- papillary calcifications
Tx for analgesic nephropathy?
Stop the drug
Good hydration
Watch for ESRD/cancer
What happens when you ingest heavy metals particularly lead?
- Filtered by glomerulus
- Transported across PCT
- Accumulates and causes cell damage
Heavy metal toxicity tx?
Chelation w EDTA to decrease serum levels
If you came here for pee jokes
Urine luck
