Medullary sponge kidney
| Classification according to ICD-10 | |
|---|---|
| Q61.5 | Medullary cystic kidney sponge kidney |
| ICD-10 online (WHO version 2019) | |
The medullary spongy kidney is a congenital disease , usually of both kidneys . There are many small cysts in the kidney medulla that are connected to the collecting ducts . There is often an increased calcium and decreased acid excretion, which can lead to stone disease and renal tubular acidosis . Affected people should drink water to avoid stone formation.
Pathogenesis
The cause of the disease are congenital changes in the collecting ducts in the medullary pyramids and papillae. The medullary sponge kidney usually occurs spontaneously and unpredictably, which is why it is currently more likely that a developmental complication occurs during pregnancy. In addition, the possibility of an autosomal dominant inheritance is discussed, whereby the disease then only occurs in connection with previously unknown environmental factors. The kidney changes can occur unilaterally or bilaterally or only affect parts of the kidney.
In the terminal collecting ducts, there is an expansion near the tip of the papilla, from which calcified cysts can form in the course, which contain abundant calcium phosphate and oxalate concretions. Most of those affected show increased calcium excretion (hypercalciuria) and decreased acid excretion (renal acidosis).
The kidneys keep their normal shape but develop a spongy appearance and are enlarged. Obstructions develop in the kidneys, which change the parenchyma secondarily without usually leading to renal insufficiency. With bilateral medullary spongy kidneys, however, around 75% of all patients develop a kidney dysfunction.
clinic
Even if the disease is congenital, it remains symptom-free for a very long time. The first symptoms appear either in adolescence or from the 5th decade of life. Common symptoms are:
- Renal colic as a result of recurring kidney stones
- Urinary tract infections (which are favored by narrowing (obstruction) of the lower urinary tract)
- Haematuria (excretion of red blood cells in the urine; especially as a result of recurrent kidney stones)
- Chronic kidney dysfunction (rare with unilateral medullary sponge kidney; especially with bilateral medullary spongy kidney)
Diagnosis
The diagnosis is made by ultrasound and, if necessary, x-ray images of the abdomen. There are multiple (radiopaque) calcifications in the papillae. In iv pyelography, the cavities in the papillae fill up first and then the areas of the calyxes.
therapy
Therapy is usually symptomatic (such as sufficient fluid intake) and is aimed in particular at the prophylaxis of kidney stone formation. In hypercalciuria, thiazide diuretics are used to reduce the excretion of calcium by the kidneys. Dehydration must be avoided, as the increased urine concentration in the context of a lack of fluids promotes the precipitation of calcium phosphate and calcium oxalate.
Life expectancy is usually not restricted.
swell
- Piper (2007) Internal Medicine. Springer publishing house
