Renal Flashcards
Dominant polycystic kidney disease
Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary human kidney disease, with an incidence of 1/500 to 1/1,000.
Both kidneys are enlarged and show cortical and medullary cysts originating from all regions of the nephron.
Although symptomatic ADPKD commonly occurs in the 4th or 5th decade of life, symptoms, including gross or microscopic hematuria, bilateral flank pain, abdominal masses, hypertension, and urinary tract infection, may be seen in children and neonates.
Renal ultrasonography usually demonstrates multiple bilateral macrocysts in enlarged kidneys, although normal kidney size and unilateral disease may be seen in the early phase of the disease.
ADPKD is a systemic disorder affecting many organ systems. Cysts may be present within the liver, pancreas, spleen, and ovaries and when present help confirm the diagnosis.
Juvenile nephronophthisis
JN is generally inherited as an autosomal recessive trait. Patients with JN typically present with polyuria, growth failure, “unexplained” anemia and chronic renal failure in late childhood or adolescence.
The clinical manifestations are related to tubular injury that leads to a reduction in urinary concentrating capacity, renal sodium loss, and insidious but inevitable progression to renal failure. The tubular defects precede the decline in renal function and may be present in asymptomatic siblings with the disease.
In most patients, the signs associated with decreased urinary concentration capacity are present by age 5 years.
The signs include polyuria, polydipsia, enuresis, and dehydration.
Common findings include a failure to thrive and weakness.
Anorexia, nausea, pruritus, bone pain, and neurologic symptoms herald ESRD.
Because of salt wasting, hypertension is rare, even in patients with severe renal insufficiency.
Pallor is another characteristic finding.
Anemia may occur before renal insufficiency develops.
This normocytic and normochromic anemia is more severe than that of other chronic renal diseases, and it does not result from iron deficiency or hemolysis.
Contrast-enhanced thin-section CT is the modality of choice.
The kidneys are imaged with 1- to 2-mm-thick sections.
Multiple cysts are typically seen in the medulla and corticomedullary region.
The cysts range from smaller than 0.5 mm to 2 cm in diameter.
Papillary necrosis
Renal papillary necrosis involves a severe destructive process that presumably results from ischemia to the medulla and papilla. The papilla is very sensitive to these ischaemic changes because even in the normal setting it is exposed to a relatively hypoxic environment. Concomitant exacerbating factors include urinary tract infection and analgesic abuse.
Clinically, papillary necrosis often manifests as flank pain, hematuria, and fever. Urinalysis reveals red and white blood cells, bacteria, and papillary fragments.
Ureteric obstruction can occur as a result of these fragments and must be addressed as an emergency.
Recessive polycystic kidney disease.
Also known as infantile polycystic disease, autosomal recessive polycystic kidney disease (ARPKD) is an autosomal recessive disorder occurring with an incidence of 1 : 10,000 to 1 : 40,000.
Both kidneys are markedly enlarged and grossly show innumerable cysts throughout the cortex and medulla. Microscopic studies demonstrate dilated, ectatic collecting ducts radiating from the medulla to the cortex, although transient proximal tubule cysts have been reported in the fetus. Development of progressive interstitial fibrosis and tubular atrophy during advanced stages of disease eventually leads to renal failure.
The typical child presents with bilateral flank masses during the neonatal period or early infancy. ARPKD may be associated with oligohydramnios, pulmonary hypoplasia, respiratory distress, and spontaneous pneumothorax in the neonatal period.
Hypertension is usually noted within the first few weeks of life and is often severe and difficult to control.
The diagnosis is supported by clinical and laboratory signs of hepatic fibrosis, pathologic findings of ductal plate abnormalities seen on liver biopsy, anatomic and pathologic proof of ARPKD in a sibling, or parental consanguinity.
Renal angiomyolipomata
Benign tumour of blood vessels
1/10 of cases seen in patients with tuberous sclerosis. Those seen in TS are bilateral.
Also seen in sporadic lymphangioleiomyomatosis (LAM)
Spontaneous bleeding can be fatal.
They grow and encroach on normal renal tissue, which can lead to ESRD
Management – partial or total nephrectomy, embolisation
