Bilateral Enlarged Kidneys
Presentation
Sir, this patient has bilateral enlarged kidneys.
There are bilateral masses in the flanks which are bimanually palpable and ballotable with a nodular surface. Of note, I am able to get above both masses. Percussion note was resonant over both kidneys and they move inferiorly with respiration. They are not tender in nature and there was no renal bruit.
There is no associated hepatomegaly and the liver span is 12 cm at the right mid-clavicualar line. The spleen is not enlarged. There is no ascites detected clinically and the bladder is not palpable or percussible.
The patient does not have a sallow appearance and not cachexic looking. There are no pruritic scratch marks or bruising. There is also no leukonychia or Terry’s nails. There is no conjunctival pallor to suggest anaemia and no features of polycythemia such as a plethoric facies or conjunctival suffusion. Patient is not in fluid overload as there is no pedal oedema, he is able to lie flat and is not oxygen dependent. There is no Kussmaul’s breathing pattern and also no flapping tremor or uremic fetor.
He does not have any acromegalic features, no DM dermopathy and no adenoma sebaceum to suggest tuberous sclerosis.
There is no evidence of renal replacement therapy such as AVF, TK cathether or a transplanted kidney.
I would like to complete my examination by
· checking the patient’s temperature chart for fever,
· blood pressure for hypertension
· fundoscopy for hypertensive changes
· urine disptick for hematuria, proteinura and pyuria
· Cardiovascular examination for signs of MVP or AR
· Neurological examination for a third nerve palsy secondary to berry aneurysm or any evidence of a stroke
· FHx of aneurysm or SAH (5% risk overall but 20% if positive FHx)
In summary, this middle age gentleman has got bilateral enlarged kidneys with no complications of chronic renal failure detected clinically. There is also no evidence that the patient is undergoing renal replacement therapy. The most underlying etiology is Adult Polycystic kidney disease.
Questions
What are the causes of bilateral enlarged kidneys?
· APCK
· Commoner
o Acromegaly (hepatosplenomegaly)
o Early diabetic nephropathy
o Bilateral hydronephrosis
· Rare
o Tuberous sclerosis
o Amyloidosis
o Von-Hippel Lindau disease
§ Autosomal dominant
§ Multiple angiomata in the retina, CNS
§ Cysts in liver, kidneys pancreas
§ RCC, phaeochromocytoma
What are the conditions that can result in bilateral renal cysts?
o Polycystic kidneys
§ Dominant and recessive
§ Simple cyst
§ Von Hippel Lindau
§ Tuberous sclerosis
What are the complications of APCK? (Renal and Extra-renal Cx)
· Fever
o UTI, pyelonephritis, pyocyst
· Hypertension (75%)
o Activation of RAA from intra-renal ischaemia from architectural distortion
o Malignant hypertension
§ Renal artery stenosis from compression
§ Renin producing cyst
· Pain
o Chronic pain
o Acute pain
§ UTI
§ Nephrolithiasis
§ Cyst rupture
§ Haemorrhage into cyst
§ Upper tract obstruction
· Massively enlarged cyst
· Clot
· Stone
· Anaemia
o CRF
o Persistent gross hematuria
· Polycythaemia
o Increased erythropoietin production
· Malnutrition
o CRF
o Bilateral renal enlargement with early satiety
· Acute renal failure
o Malignant hypertension
o UTI
o Nephrolithiasis (Uric acid)
· Chronic renal failure
· Renal cell carcinoma (rare)
· Extra-renal
o Abdominal – cysts in liver, spleen, pancreas, ovaries; colonic diverticular disease
o Cardiac – MVP(25%), AR, TR
o Intracranial aneurysm (III nerve palsy), SAH (3%)
What are the complications of CRF?
· Fluid
· Electrolytes – Hyperkalaemia
· Acid-base – Metabolic acidosis
· Uremia and its complications
· Hypertension
· Anaemia (NCNC)
· Secondary and tertiary hyperparathyroidism
· Renal bone disease
Why are patients with CRF sallow?
· Impaired execretion of urinary pigments combined with anaemia
What are the types of signs in the nails that you can detect in patients with CRF?
· Hypoalbuminaemia
o Leukonychia
o Muehrcke’s nails (paired white transverse line near the distal end of nails)
· Renal failure
o Terry’s nails (distal brown arc 1mm or >)
o Mee’s line (single white line; also in arsenic poisoning)
o Beau’s line (non-pigmented indented band = catabolic state)
What are the causes of anaemia in patients with CRF?
· Erythropoeitin deficiency
· Anaemia of chronic disease
· Fe deficiency anaemia – blood loss, nutrition
· Folate deficiency – nutrition
What is Adults Polycystic Kidney disease?
· Multisystemic, progressive disease, 1 in 400 to 1 in 1000 people
· Characterised by cysts formation and enlargement in the kidneys and other organs
· Autosomal dominant with almost 100% penetrance
· Focal cystic dilatation of the renal tubules
· 2 predominant type
o 85% - APCKD 1 on Ch 16
o 15% - APCKD 2 on Ch 4
o 3rd type of which loci is not fully known
· Presents clinically in the 3rd or 4th decades with
o Hematuria, hypertension, recurrent UTI, pain and uremia
o Stroke
· By age 60 years, 50% will require RRT
· Poorer Px – males, PCK 1 and early onset of clinical features
· Mortality
o ESRF (1/3)
o Stroke and other hypertensive Cx (1/3/)
o Others
How do you investigate?
· Blood Tests
o FBC
o Biochemical
o CRF – Ca, PO4, iPTH, Uric acid, urinalysis
· USS (useful >20 years old); Ravine’s criteria
o At risk patients, 20-30yrs: 2 cysts in 1 kidney or 1 cyst in each kidney
o At risk patients, 30-60 yrs: 2 cysts in each kidney
o At risk patients, >60 yrs: 4 cysts in each kidney
· Other imaging(CT and MRI)
· MRA for patients with high risk of an aneurysm, Ba enema and Echocardiogram
· Genetic testing
o For young people with no cysts on USS who are potential organ donors
How would you manage?
· Education and counselling, regular follow up, screening of first degree relatives
· Avoidance of medications that can precipitate renal impairment such as NSAIDs or tetracycline antibiotics
· Medical treatment
o Hypertension with ACE inhibitors or ATII RA
o UTI, cysts infection – usually GN bacteria therefore use Bactrim or fluroquinolones with good renal tissue penetration
o Pain treatment
o Renal failure – medical treatment and RRT for those with ESRF
o Antibiotic prophylaxis
· Surgical treatment
o Pyocyst – drainage
o Cystectomy
o Nephrectomy
o Alcohol sclerosant
o RRT
o Aneurysm clipping, MVP with MR
