In terms of history, onemust determine whether previous serum creatinines are available or if thereis any history of any systemic diseases that may be associated with renalinvolvement. Often, one must take the time to call otherphysicians or hospitals to get old creatinine values.
When it seems that one isdealing with acute renal failure then there needs to be an assessment forprerenal, renal or post-renal causes.
On physical examination, oneshould look for evidence of a pre-renal cause of renalinsufficiency. Hypovolemia would be suggested byfeatures of decreased extracellular fluid volume such as a low JVP, drymucous membranes or postural tachycardia or hypotension.Pre-renal disease can also be due to conditions such as congestiveheart failure or cirrhosis, so one should also perform a careful cardiacexam and look for stigmata of chronic liver disease.Post-renal failure can be seen in bladder outlet obstruction, so onecould feel for a palpable bladder. Intrinsic renaldisease can develop acutely due to systemic disease with renal involvement.One can look for features of some of these systemic conditions which mightinclude rashes, active joints, alopecia, oral/nasal ulcers, peripheralneuropathy, or a murmur from endocarditis.
In terms of lab data,urinalysis is critical. One may see casts that willhelpful in terms of diagnosis: RBC casts for glomerulonephritis, WBC castsin acute interstitial nephritis and heme granular casts in acute tubularnecrosis. In chronic renal disease, one may see waxy orbroad casts.
Chronic renal failure may alsobe associated with anemia, metabolic acidosis, hypocalcemia andhyperphosphatemia. These may not be entirely reliable,however, as anemia can develop acutely in patients with conditions such aslupus or vasculitis, and hypocalcemia/hyperphosphatemia can be seen inconditions such as tumour lysis syndrome.
On ultrasonography, smallkidneys with cortical echogenicity would suggest kidney disease ischronic. If kidney size is preserved this might suggestacute renal failure, though some diseases of the kidney are associated withpreservation of renal size (examples include diabetic nephropathy andamyloidosis).
When it seems that one isdealing with acute renal failure then there needs to be an assessment forprerenal, renal or post-renal causes.
On physical examination, oneshould look for evidence of a pre-renal cause of renalinsufficiency. Hypovolemia would be suggested byfeatures of decreased extracellular fluid volume such as a low JVP, drymucous membranes or postural tachycardia or hypotension.Pre-renal disease can also be due to conditions such as congestiveheart failure or cirrhosis, so one should also perform a careful cardiacexam and look for stigmata of chronic liver disease.Post-renal failure can be seen in bladder outlet obstruction, so onecould feel for a palpable bladder. Intrinsic renaldisease can develop acutely due to systemic disease with renal involvement.One can look for features of some of these systemic conditions which mightinclude rashes, active joints, alopecia, oral/nasal ulcers, peripheralneuropathy, or a murmur from endocarditis.
In terms of lab data,urinalysis is critical. One may see casts that willhelpful in terms of diagnosis: RBC casts for glomerulonephritis, WBC castsin acute interstitial nephritis and heme granular casts in acute tubularnecrosis. In chronic renal disease, one may see waxy orbroad casts.
Chronic renal failure may alsobe associated with anemia, metabolic acidosis, hypocalcemia andhyperphosphatemia. These may not be entirely reliable,however, as anemia can develop acutely in patients with conditions such aslupus or vasculitis, and hypocalcemia/hyperphosphatemia can be seen inconditions such as tumour lysis syndrome.
On ultrasonography, smallkidneys with cortical echogenicity would suggest kidney disease ischronic. If kidney size is preserved this might suggestacute renal failure, though some diseases of the kidney are associated withpreservation of renal size (examples include diabetic nephropathy andamyloidosis).
