Renal stones
●Most of renal stones 90 % composed of Ca salts,
types of renal stonesare the following :-
Ca oxalate.
Ca phosphate.
Magnesium - ammonium phosphate stones.
Urea acid stones.
Cystine stones.

Predisposing factors :

1 - Metabolic causes

A- Ca stones : mainly Ca oxalate & Ca phosphate associated
with : Hypercalcuria
Sarcoidosis.
Vit D intoxication.
Hyperparathyroidism.
Renal tub. acidosis.
Idiopathic.
B- Uric acid stone : in hyperuricemia & hyperuricosuria.
C- Cystine stones Cystinuria.

2-Obstruction & infection

Urinary tract infection stasis epith. Debris + pus debris

act as nidus

stones deposition of crystals

3-Dietary factors Milk &its products Ca stones.

4-Climate hot weather with excessive sweating.

5-Primary renal disease
-
Polycystic kidney. –medullary sponge kidneys.
Path.
Oxalate stone :

usually brownish, mamillated, single, or multiple,

haematuria
Uric acid stone :
whitish, smooth, single, multiple, radiolucent.

Phosphate:
whitish, single, multiple, present in alkaline urine. radioopaque laminated.


Cystine:
single or multiple radioopaque

Deposition of Ca in the renal parenchyma may lead
to nephrocalcinosis. This may occur in hyperparathyroidism, renal T. B., vit D intoxication & renal tubular acidosis
Stag horn calculi:
may fill the renal pelvis & branch into the calyces.

Presentation of renal stones
O M U M I
Obstruction migration ulceration metaplasia Infection

hydronephrosis colic haematuria malignancy pyelonephritis

C/P
Asymptomatic
Renal colic loin
radiates to groin
for few hrs
days
Post renal acute renal failure.
Chronic renal failure.
O/E
tender loin.
palpable kidney with hydro or pyonephrosis..
Signs of renal failure.

Investig.

X-ray
All stones are radioopaque.
Pure Uric acid, radiolucent
(with Ca deposition radioopaque).
Urine RBCs (painful haematuria)
pus cell with 2 ry infection.
Crystals e.g. oxalate, phosphate, urate
S. Ca, uric acid, 24h urinary Ca , urate ,oxalate.
I V P
back pressure, stone utreter.
Sonar back pressure, stone, kidney.
Renal scan reveals obstruction.

ttt

I- Medical ttt :
renal colic bed rest - warmth to loin.
Analgesics : morphia 15-30 mg or
pethidine 100 mg I.M.
antispasmodic atropine sulfate.
NSAID antiprostaglandin
(nephrotoxic).
Infusion method by
I.V.drip

(Saline + atropine + papaverine)
ttt of stones (fluids + antispasmodics + diuretics)
stones may pass spontaneously if small < 0.5 cm diameter.



Specific ttt according to type of stone :
ªCa stones.

-Idiopathic Hypercalcuria ttt : thiazides ¯ Ca in urine
-Primary hyperparathyroidism ttt : surgery
- R. tub. acidosis Na HCO3.
ªOxalate stones ttt : cholestyramine can bind oxalate.

-Oxaluria is due to over absorption of dietary
Oxalate (intestinal oxaluria) Ca oxalate stone.
-Na HCO3 used to treat all types of stones but, Vit C treat
phosphate stones.

ªUric acid stone

ttt:Fluids.
Na HCO3.
Allopurinol
ªCystine stone

ttt : Fluids.
Alkali (Na HCO3).
Penicillamine.

Diet for prophylaxis
Ample of fluids
Milk
¯ & cheese in Ca stones.
¯ spinach rhubarb in oxalate stones.
¯ liver, ¯kid., ¯ sardines in uric stones.

II- Surgical ttt:

Indications 1- Big stone. 2- Multiple stones
3- Staghorn stone.
4- Stone in renal pelvis.
5-Complicated with hydronephrosis.
Surgical & instrumental tt see surgery.

Source: Internal Medicine Book of Dr.Osama Mahmoud (Ain Shams University)