Renal Calculi (Kidney Stones)

Kidney stones, also called renal calculi, are solid concretions (crystal aggregations) of dissolved minerals in urine; calculi typically form inside the kidneys or bladder. The terms nephrolithiasis and urolithiasis refer to the presence of calculi in the kidneys and urinary tract, respectively.
Types of Renal Calculi

There are five types of kidney stones:

1. Calcium phosphate stones

2. Calcium oxalate stones

3. Struvite stones - Magnesium ammonium phosphate

4. Uric acid stones - Result from a problem metabolizing purines (the chemical base of adenine, xanthine, theobromine [in chocolate] and uric acid). They may form in a condition such as gout.

5. Cystine stones - Rare- Result from a hereditary inability to reabsorb cystine. Most children's stones are this type.



Symptoms of kidney stones include

  • Colicky pain: "loin to groin". Often described as "the worst pain [...] ever experienced".
  • Hematuria: blood in the urine, due to minor damage to inside wall of kidney, ureter and/or urethra.
  • Pyuria: pus (white blood cells) in the urine.
  • Dysuria: burning on urination when passing stones (rare). More typical of infection.
  • Oliguria: reduced urinary volume caused by obstruction of the bladder or urethra by stone, or extremely rarely, simultaneous obstruction of both ureters by a stone.
  • Abdominal distension.
  • Nausea/vomiting: embryological link with intestine – stimulates the vomiting center.
  • Fever and chills.
  • Hydronephrosis
  • Postrenal azotemia: when kidney stone blocks ureter