CYSTIC RENAL DISEASE Solitary or multiple renal cysts are common ,especially with advancing age.

1. CYSTIC RENAL DISEASE Solitary or multiple renal cysts are common ,especially with advancing age. *Cysts are often asymptomatic and are found on excertion urography or ultrasound examination performed for some other reason. *Malignant tumor transformation seems to be more common in such kidneys than in general population.

2. Autosomal-dominant polycystic kidney disease(APCKD) *Is by far the most common inheritd nephropathy And in about 85% of the cases,the gene responsible(PKD1) has been located on chromosome 16 . *An inherited disorder usually presenting in adult life. *Is characterized by the development of multiple renal cysts,variably associated with extrarenal( mainly hepatic and cardiovascular) abnormalities.

3. *A second gene,PKD2 which has been mapped on chromosome 4, accounts for the vast majority of the other cases. Clinical features Clinical presentation may be at any age from the second decade.Presenting symptoms include: *Acute loin pain and/or haematuria owing to haemorrhage into a cyst,cyst infection or urinary tract stone formation.

4. *Loin or abdominal discomfort owing to the increasing size of the kidneys. *Subarachnoid haemorrhage associated with berry aneurysm rupture. *Complications of hypertension. *Complications of associated liver cysts. *Symptoms of uraemia and/or anaemia associated with chronic renal failure.

5. *The natural history of the disease is one of progressive renal impairment, sometimes punctuated by acute episodes of loin pain and haematuria,and commonly associated with the development of hypertension. *The progression to renal failure is variable. *In the PKD2 form,renal cysts develop more slowly and end-stage renal failure(ESRF) occurs 10-15 years later than in the PKD1 form.

6. Complications and associations 1.Pain: *A minority of the patients suffer chronic renal pain resistant to common analgesics, presumably owing to pressure effects of large cysts. *Surgical decompression of such cysts appears to be of benefit in about 2/3 of patients.

7. 2.Cyst infection *The response to standard antibacterial therapy is often poor owing to poor penetration of conventional antibiotics across the cyst wall. *Lipophilic antibiotics active against Gram-negative bacteria,such as co-trimoxazole and fluoroquinolones, penetrate into the cysts better and their use has greatly improved the treatment of this complication.

8. 3.Renal calculi *These are diagnosed in about 10-20% of patients with ADPKD.Frequently they are composed of uric acid and hence radiolucent. *Obstructing or painful stones are treated no differently than are stones in patients with normal urinary tracts.

9. 4.Hypertension *Is an early and very common feature of ADPKD and is associated with an increase in left ventricular mass. *Intrarenal activation of the renin-angiotensin system is involved in the pathogenesis,and ACE inhibitors are logical first-line agents in treatment.Early control of blood pressure is essential as cardiovascular complications are a major cause of death in ADPKD.

10. 5.Progressive renal failure *This is the most serious complication of ADPKD. *The probability of being alive without requiring dialysis or transplantation by the age of 70 years is of the order of 30% 6.Hepatic cysts *Approximately 30% of patients have hepatic cysts and in minority of patients massive enlargement of the polycystic liver is seen. *Pain,infection of the cysts and ,more rarely, compression of the bile ducts,portal vein or hepatic venous outflow occur.

11. 7.Intracranial aneurysm formation *About 10% of ADPKD patients have asymptomatic intracranial aneurysm. *Headache of sudden onset or unusual character or severity in a patient with ADPKD should prompt investigation. 8.Mitral valve prolapse This is found in 20% of individuals with ADPKD.

12. Diagnosis Physical examination commonly reveals large ,irregular kidneys and possibly hepatomegaly.Definitive diagnosis is established by ultrasound examination. Screening The children and siblings of patients with ADPKD should, in general, be offered screening.Affected individuals should have regular blood pressure checks and should be offered genetic counselling.

13. *Screening by ultrasonography should not be carried out before the age of 20 years, as excluding the condition may be difficult and hypertension is unusual before this age.Even at age 20 ,renal ultrasonography may give a false-negative result.Gene linkage analysis can be utilized in many families.

14. Therapy *No therapy is yet available but potential agents include vasopressin receptor antagonists have halted cyst progression or caused disease regression. *ADPKD kidneys may be particularly vulnerable to adenylyl cyclase agonists or cAMP phosphodiesterase inhibitors.

16. Medullary sponge kidneys *Manifests with stones or UTI in infants. *Normal life expectancy. *Asymmetrically enlarged kidneys. *Probably underdiagnosed ( as idiopathic hypercalciuria) in calcium stone-formers;IVP…..’grapelike clusters’ *Presents between 10 and 40 years of age( bimodal) 60% get calculi ; usually oxalate.

17. *30% get: -Haematuria -Urinary tract infections -Papillary necrosis/nephrocalcinosis *Does not usually lead to uraemia ; may be totally asymptomatic. *Instrumentation should be avoided if possible.

18. Medullary cystic disease *Causes renal failure and osteodystrophy in childhood. *Associated with liver fibrosis and retinitis pigmentosa. *Asymmetrically shrunken kidneys. *Histology similar to chronic interstitial nephritis. *Hypertension is rare. *Urinalysis typically normal. *No calcification on IVP. *Progresses inexorably to uremia via proximal RTA and/or salt-losing nephropathy.