Cerebrospinal fluid (CSF) TRAP. A method to improve CSF laboratory efficiency.

Establishment of a procedure termed cerebrospinal fluid (CSF) TRAP ("Transport and Rapid Accessioning for Additional Procedures") allows clinicians to appropriately store, at -75 degrees C, and rapidly access CSF specimens. The CSF TRAP enhances patient care by decreasing the need for repeat lumbar punctures and providing reserve fluid for the following: (1) further CSF testing; (2) repeating questionable test results; and (3) laboratory accidents. The CSF TRAP has been approved for third-party payment because it promotes efficient laboratory utilization by encouraging clinicians to review initial CSF findings before ordering low-yield CSF assays such as the venereal disease research laboratory (VDRL) and cryptococcal antigen latex agglutination tests.

Establishment of a CSF bank.

A bank of well-characterized CSF has been established by collecting and storing (-70 degrees C) CSF samples remaining after completion of routine clinical studies. Over 1,700 individual patient samples were collected during a 12-month period. A database derived largely from information down-loaded from existing hospital-based systems includes the results of individual CSF laboratory studies, in addition to the patient age, primary diagnoses, and details of any malignancy.

Low-dose chenodiol to prevent gallstone recurrence after dissolution therapy.

Chenodiol is a safe and effective agent for the medical dissolution of gallstones in selected patients; however, after dissolution and cessation of treatment, gallstones recur. This study was done to determine the recurrence rate after successful medical treatment and cessation of chenodiol therapy; compare the efficacy and safety of low-dose chenodiol, as compared to placebo, for prophylaxis against recurrence; and identify factors predictive of recurrence. In a randomized, double-blind fashion, 53 patients with gallstone dissolution received either chenodiol, 375 mg/d, or placebo, for at least 2 years.

Central laboratory quality control in the National Cooperative Gallstone Study.

This article presents the rationale, selection, operation, and quality control of the Central Serum and Central Bile Laboratories utilized by the National Cooperative Gallstone Study. The external quality control protocols were designed to monitor long-term stability of the analytical procedures and to measure the precision of the measurements as affected by the collection, labelling, storage, shipping, and laboratory methods. For both laboratories, the assessment of long-term stability by pool standards failed to produce the data necessary to come to relevant conclusions.