Fluid and Electrolytes

Dehydration

Edema

Hyperkalemia

Metabolic acidosis

Calcium Phosphate and Bone

Hyperphosphatemia

Hypocalcemia

Secondary hyperparathyroidism

Renal osteodystrophy

Hematologic

Anemia

Bleeding diathesis

Cardiopulmonary

Hypertension

Congestive heart failure

Pulmonary edema

Uremic pericarditis

Gastrointestinal

Nausea and vomiting

Bleeding

Esophagitis, gastritis, colitis

Neuromuscular

Myopathy

Peripheral neuropathy

Encephalopathy

Dermatologic

Sallow color

Pruritus

Dermatitis

Congenital Anomalies

About 10% of all people are born with potentially significant malformations of the urinary system. Renal dysplasias and hypoplasias account for 20% of chronic renal failure in children.

Autosomal-dominant polycystic kidney disease, a congenital anomaly that becomes apparent in adults, is responsible for about 10% of chronic renal failure in humans.

Congenital renal disease can be hereditary but is most often the result of an acquired developmental defect that arises during gestation. As was discussed in Chapter 10 , defects in genes

involved in development, including the Wilms tumor (WT1)-associated genes, cause urogenital anomalies. As a rule, developmental abnormalities involve structural components of the

kidney and urinary tract. However, genetic abnormalities also cause enzymatic or metabolic defects in tubular transport, such as cystinuria and renal tubular acidosis. Here, we restrict the

discussion to structural anomalies involving primarily the kidney. All except horseshoe kidney are uncommon. Anomalies of the lower urinary tract are discussed in Chapter 21 .

Agenesis of the Kidney.

Total bilateral agenesis, which is incompatible with life, is usually encountered in stillborn infants. It is often associated with many other congenital disorders (e.g., limb defects,

hypoplastic lungs) and leads to early death. Unilateral agenesis is an uncommon anomaly that is compatible with normal life if no other abnormalities exist. The opposite kidney is usually

enlarged as a result of compensatory hypertrophy. Some patients eventually develop progressive glomerular sclerosis in the remaining kidney as a result of the adaptive changes in

hypertrophied nephrons, discussed later in the chapter, and in time, chronic renal failure ensues.

Hypoplasia.

Renal hypoplasia refers to failure of the kidneys to develop to a normal size. This anomaly may occur bilaterally, resulting in renal failure in early childhood, but it is more commonly

encountered as a unilateral defect. True renal hypoplasia is extremely rare; most cases reported probably represent acquired scarring due to vascular, infectious, or other parenchymal

diseases rather than an underlying developmental failure. Differentiation between congenital and acquired atrophic kidneys may be impossible, but a truly hypoplastic kidney shows no

scars and has a reduced number of renal lobes and pyramids, usually six or fewer. In one form of hypoplastic kidney, oligomeganephronia, the kidney is small but the nephrons are

markedly hypertrophied.

Ectopic Kidneys.

The development of the definitive metanephros may occur in ectopic foci, usually at abnormally low levels. These kidneys lie either just above the pelvic brim or sometimes within the

pelvis. They are usually normal or slightly small in size but otherwise are not remarkable. Because of their abnormal position, kinking or tortuosity of the ureters may cause some

obstruction to urinary flow, which predisposes to bacterial infections.

Horseshoe Kidneys.

Fusion of the upper or lower poles of the kidneys produces a horseshoe-shaped structure that is continuous across the midline anterior to the great vessels. This anatomic anomaly is

common and is found in about 1 in 500 to 1000 autopsies. Ninety per cent of such kidneys are fused at the lower pole, and 10% are fused at the upper pole.

Date: 2016-04-22; view: 785