F- CLINICAL ASPECTS OF SPINAL CORD INJURIES
411
are oliguria, anaemia, derangement in the ratio between blood and urine osmolality and
disturbances in the urine sodium and potassium concentrations. Tubular damage leading
to irreversible tubular necrosis is the detrimental result, if proper management is not
applied as early as possible. Therefore, in view of the therapeutic advances made in
recent years, early diagnosis of renal deficiency is vital, and the determination of tubular
concentration in the presence of oliguria as well as regular blood pressure readings and,
above all, careful and detailed examination of the urinary sediment are of utmost import
ance. Unfortunately, in spinal cord injuries, the bacterial examination of the urine,
important as it is, has become so routine that sometimes the proper evaluation of the
urinary sediment is neglected. As is well known, the presence of red cells, particularly
red cell casts, is indicative of glomerular damage; granular casts indicate parenchymal
renal damage, and the presence of a necrosed papilla may indicate necrotizing papillitis.
As pointed out earlier (page 350), increase of protein, white cells and epithelial cells
indicates acute inflammation of bladder or ureter, even in the absence of bacteriuria, or
may be the precursor of bacterial infection.
Comparative studies on the endogenous creatinine and urea clearances were under
taken at various stages following spinal cord injuries (Doggart, Guttmann & Silver, 1966).
Special attention was paid to renal function in the immediate and very early stages of
complete traumatic lesions. The creatinine clearance test was found superior to the urea
clearance test as a measure ofglomerular filtration rate. In the immediate stages, glomerular
filtration rate, as indicated by the creatinine clearance test, was found remarkably normal.
In contrast, the blood urea level was profoundly raised as a reflection of tissue breakdown.
Only in one case (Tio complete), associated with disruption of the pelvis and bilateral
haematoma of the groin, was the serum creatinine found to be raised on the first day
following injury (2-7 mg per cent); clearance was 73 ml/min, blood urea 83 mg per cent.
There was oliguria which, however, improved, and on the second day serum creatinine
was 0-9 mg per cent and blood urea 44 mg per cent. The level of the complete lesion was
found to have no significant influence on renal function.
Although creatinine clearance is generally considered as the most reliable method of
detecting renal damage, it may not be possible to detect very early deterioration of renal
function with this method owing to the ability of the kidney to compensate. In recent
years, Bernier
et al.
(1968) and Harrison
et al.
(1968) found that B-2-microglobuUn—a
low molecular globulin fraction, described by Berggard and Bern (1968)—is increased
in patients with renal disease proportional to the degree of renal dysfunction. This low
molecular weight protein is produced in the body by lymphocytes and its urinary excre
tion is markedly increased in patients with dysfunction of the renal tubuli which normally
catabolize B2-microglobulin. Therefore, in normal circumstances, Bo-microglobulin is
present in only trace amounts in human serum and urine. Recently, Lindan
et al.
(1972)
confirmed increased high serum levels and increased urinary excretion and clearance of
B2-microglobulin in 17 out of 25 paraplegics and tetraplegics. From these findings, it
would appear that the B2-microglobulin test is more sensitive as compared with standard
renal function tests such as creatinine clearance. X-ray and protein.
