Urinary Amylase Excretion Research Articles

The hourly rate of urinary amylase excretion, serum amylase, and serum lipase: Part II Patients with gastrointestinal and pancreatic disorders

The hourly rate of urinary amylase excretion, serum amylase, and serum lipase: Part II Patients with gastrointestinal and pancreatic disorders

The hourly rate of urinary amylase excretion, serum amylase, and serum lipase. I. In control subjects and patients with renal disease.

The rates of urinary amylase excretion/hour and the levels of serum amylase and lipase were measured in 190 normal subjects and patients with no evidence of renal or gastrointestinal disorder. The hourly rate of urinary amylase excretion/hour was found to have an upper limit of normal of 69 IU. The upper limit of normal for the serum amylase was 251 IU/litre and for the serum lipase 1.6 units/ml. Raised levels of serum amylase and lipase with a normal rate of urinary amylase excretion/hour were found in chronic renal failure.

Distribution, turnover, and mechanism of renal excretion of amylase in the baboon.

Pure amylase was isolated from pancreata and parotid glands of the baboon, an animal which has a serum amylase level and renal clearance of amylase (C(Am)) similar to man. After bolus injection, both pancreatic and salivary amylase rapidly disappeared from the serum in a monoexponential fashion with a mean serum half-time of approximately 83 min. Only about 24% of the amylase cleared from the serum appeared in the urine indicating that the majority of amylase was removed from the serum by an extraurinary mechanism. The C(Am) by the kidney was constant over a wide range of serum amylase levels and the ratio of C(Am)/C(In), which averaged 3.0%, was not influenced by mannitol diuresis. This suggests that the renal excretion of amylase results from glomerular filtration without appreciable tubular reabsorption. Pancreatic amylase was consistently cleared more rapidly by the kidney than was the baboon's endogenous amylase while salivary amylase was consistently cleared less rapidly than endogenous amylase. THE FINDINGS IN THIS STUDY PROVIDE INSIGHT INTO SEVERAL OF THE FOLLOWING CLINICALLY OBSERVED PHENOMENA: (a) the short serum half-time of amylase accounts for the transient nature of serum amylase elevations in pancreatitis; (b) the extra-urinary removal of amylase accounts for the maintenance of relatively normal amylase levels in uremia; and (c) the more rapid renal clearance of pancreatic amylase compared to salivary amylase may explain the disproportionate elevation of the urinary amylase excretion rate relative to the serum amylase level in acute pancreatitis.

A CASE OF MACROAMYLASAEMIA

A further case of macroamylasæmia is described. The two known forms of macroamylasæmia are discussed, and a review of clinical findings and ætiology is presented. Macroamylasæmia should be suspected in patients who have a persistently raised serum amylase level, but normal urinary amylase excretion, as surgical exploration is unnecessary in this condition.

Amylase and lipase values in normal subjects

In 146 hospitalized individuals (71 men and 75 women), the simultaneous fasting serum amylase and lipase concentrations and the urinary amylase excretion per 24 h were determined. Patients with pancreatic abnormalities or other diseases which might produce abnormal enzyme values were ruled out from this study. Age and sex were found not to influence the parameters under investigation. The various parameters failed to show a distinct correlation. The renal amylase clearance was calculated for the individuals, and the frequency distribution is presented. In 10 normal subjects, the postprandial 3-h urinary amylase excretion was found not to differ from the preprandial value. In 10 normal subjects, the course of the 24-h urinary amylase excretion showed no distinct rhythm. The urinary amylase excretion per 24 h probably constitutes a more reliable parameter than the excretion during a brief period of collection or the fasting amylase concentration.

Clinical significance of urinary amylase determinations in diagnosis of pancreatic diseases

1) For evaluating pancreatic diseases with Wohlgemuth’s method of amylase determination, the significant values lie only above 64 unit, and in the low units (2–8) there is no significance suggesting pancreatic abnormalities. 2) Serial determination on urinary amylase excretion is recommended for diagnosing of chronic pancreatic disorders. 3) It is suggested that urinary amylase is more closely related to pancreatic states than serum amylase from the observations of amylase isozyme pattern.

Comparison of Urinary and Serum Amylase Values Following Pancreatic Stimulation in Patients with and without Pancreatic Disease

Summary Serum amylase concentrations and urinary amylase excretion rates were studied before and after pancreatic stimulation in 23 controls and 31 patients with pancreatic disease. The urinary amylase excretion rate increased substantially after stimulation in 20 of 31 patients with pancreatic disease, or 65%, while serum amylase increases were found in only 6 of the 31, or 19%.

URINARY AMYLASE VS SERUM AMYLASE IN PATIENTS WITH PANCREATIC CARCINOMA.

IN A RECENT publication we presented data indicating that in the presence of pancreatitis the one-hour value for urinary amylase exceeded normal more often, in a larger number of patients, and frequently for a longer period of time, than did the values for serum amylase and serum lipase.¹The encouraging results of those observations and of those made previously by Saxon and co-workers²led us to study the relative abnormality of the results obtained with these tests for these enzymes in pancreatic carcinoma. <h3>Material and Method</h3> The data on tests for serum amylase and lipase and urinary amylase were obtained from the records of 192 patients with pancreatic carcinoma proved by surgical exploration. Review of the case records included a search for evidence of concomitant or ancient pancreatitis as well as pancreatic carcinoma. The urinary excretion of amylase was measured by a modification of the method of Huggins

Comparative Value of Serum and Urinary Amylase in The Diagnosis of Acute Pancreatitis

The very great importance of a rise in serum amylase concentration for verifying a suspicion of pancreatitis is generally recognized, as is the difficulty that would be encountered in diagnosis without some such measure. Not so widely appreciated is the fact that the serum amylase often fails us, particularly if the episode is mild or the patient is not seen within the first few days. Clearly, any measure of the outpouring of amylase from the pancreas that improves upon the serum concentration should have great practical value. Though much has been written about urinary amylase, the data and conclusions are conflicting, and in consequence urinary amylase excretion is infrequently used in practice. Since amylase is freely excreted by the kidney it seemed reasonable, on a little reflection, to expect the urinary excretion to give information when the serum concentration could not. This is seen from a consideration of the following