Uraemia Health Dictionary

The presence of excess urea and other chemical waste products in the blood, caused by kidney failure.

The clinical state which results from renal failure (see KIDNEYS, DISEASES OF). It may be due to disease of the KIDNEYS or it may be the result of pre-renal causes where a lack of circulating blood volume inadequately perfuses the kidneys. It may result from acute necrosis in the tubules of the kidney or it may result from obstruction to the out?ow of URINE.

The word uraemia means excess UREA in the blood; however, the symptoms of renal failure are not due to the abnormal amounts of urea circulating, but rather to the electrolyte disturbances (see ELECTROLYTES) and ACIDOSIS which are associated with impaired renal function. The acidosis results from a decreased ability to ?lter hydrogen ions from blood into the glomerular ?uid: the reduced production of ammonia and phosphate means fewer ions capable of combining with the hydrogen ions, so that the total acid elimination is diminished. The fall in glomerular ?ltration also leads to retention of SODIUM and water with resulting OEDEMA, and to retention of POTASSIUM resulting in HYPERKALAEMIA.

The most important causes of uraemia are the primary renal diseases of chronic glomerular nephritis (in?ammation) and chronic PYELONEPHRITIS. It may also result from MALIGNANT HYPERTENSION damaging the kidneys and amyloid disease destroying them. Analgesic abuse can cause tubular necrosis. DIABETES MELLITUS may cause a nephropathy and lead to uraemia, as may MYELOMATOSIS and SYSTEMIC LUPUS ERYTHEMATOSUS (SLE). Polycystic kidneys and renal tuberculosis account for a small proportion of cases.

Symptoms Uraemia is sometimes classed as acute – that is, those cases in which the symptoms develop in a few hours or days – and chronic, including cases in which the symptoms are less marked and last over weeks, months, or years. There is, however, no dividing line between the two, for in the chronic variety, which may be said to consist of the symptoms of chronic glomerulonephritis, an acute attack is liable to come on at any time.

Headache in the front or back of the head, accompanied often by insomnia and daytime drowsiness, is one of the most common symptoms. UNCONSCIOUSNESS of a profound type, which may be accompanied by CONVULSIONS resembling those of EPILEPSY, is the most outstanding feature of an acute attack and is a very dangerous condition.

Still another symptom, which often precedes an acute attack, is severe vomiting without apparent cause. The appetite is always poor, and the onset of diarrhoea is a serious sign.

Treatment The treatment of the chronic type of uraemia includes all the measures which should be taken by a person suffering from chronic glomerulonephritis (see under KIDNEYS, DISEASES OF). An increasing number of these patients, especially the younger ones, are treated with DIALYSIS and/or renal TRANSPLANTATION.

n. the presence of excessive amounts of urea and other nitrogenous waste compounds in the blood. These waste products are normally excreted by the kidneys in urine; their accumulation in the blood occurs in kidney failure and results in nausea, vomiting, lethargy, drowsiness, and eventually (if untreated) death. Treatment may require dialysis or transplantation. —uraemic adj.