1088 Clinical Correlations of CSF Endotoxin-Like Activity in Gram-Negative Meningitis

Abstract

Aseries of computer programs was developed uslng an e x i s t i n g d a t a base management system (KnowledgeMan) on a microcomputer t o a s s i s t with t h e management of a diagnostic virology l a b . The primary purpose was t o handle t h e d a i l y r o u t i n e : recording specimens and p a t i e n t d a t a , generating worksheets f o r t h e reading and processing of c u l t u r e s , r e t r i e v i n g c u l t u r e r e s u l t s o r current s t a t u s , and p r i n t i n g f i n a l r e p o r t forms. Ir can a l s o handle othe r l a b procedures: Chlamydia c u l t u r e s , Clostridium d i f f i c i l e toxi n assays, and some serologic t e s t i n g . In addition, t h e computer f a c i l i t a t e s s u r v e i l l a n c e s t u d i e s . I t can r a p i d l y generate a l i s t of c u l t u r e s o r r e s u l t s f o r user-defined conditions: ages, hospit a l location, d a t e s , o r a v a r i e t y of o t h e r parameters. A s t a t i st i c s package i s included f o r simple analyses. Security of pat i e n t d a t a i s always a concern with computer use because of t h e ease of t r a n s p o r t i n g l a r g e volumes of information on floppy d i s k s . Security i s provided by KnowledgeMan. A l l information i s s t o r e d i n scrambled form within f i i e s , and cannot be read i f accessed from o u t s i d e KnowledgeMan. On entering t h e system, each u s e r i s assigned a p r i o r i t y s t a t u s . Each d a t a type, e . g . name, age, r e s u l t , i s assigned up t o 16 d i f f e r e n t access codes t o r es t r i c t t h e u s e r t o c e r t a i n pieces of information. The s e r i e s of programs i s menu-driven, and r e q u i r e s no computer knowledge by l a b personnel. A computer can decrease s i g n i f i c a n t l y t h e paperwork done by hand, f i l e l a r g e amounts of information i n a small space, f a c i l i t a t e epidemiologic surveys, and provide a r a p i d r eview and a n a l y s i s of t h e work performed by t h e laboratory. Detection of endotoxin-like a c t i v i t y (EL?.) i n cerebrospinal f l u i d (CSF) by limulus amebocyte l y s a t e (LAL) g e l a t i o n has been suggested t o be a u s e f u l technique f o r diagnosis of gram-negative meningitis. W e prospectively screened 1503 CSF specimens with a microassay u t i l i z i n g 20 p 1 of CSF added t o 20 u 1 of limulus reagent on an endotoxin-free s l i d e . Specimens and c o n t r o l s were observed f o r g e l formation a f t e r 60 minutes incubationat37"C i n a moisture chamber. S e r i a l d i l u t i o n s of CSF were used t o quantit a t e EL?.. The l i m i t of s e n s i t i v i t y of the assay was 0.01 ng/ml. A l l ELA p o s i t i v e (+) specimens were subjectedtoconfirmatory ret e s t i n g , a f t e r which 49 (3.3%) were ELA (+). Comparison w i t h t h e 38 a v a i l a b l e c u l t u r e r e s u l t s revealed t h a t 33 specimens (87%) were c u l t u r e (+), t h a t 3 of t h e 5 c u l t u r e negative (-) specimens were from p a t i e n t s on therapy f o r gram-negative...