No abstract

Detection of endotoxinlike activity in cerebrospinal fluid by Limulus amebocyte lysate gelation has been suggested as a useful technique for the diagnosis of gram-negative bacterial meningitis. We prospectively screened 1,503 cerebrospinal fluid specimens with a Limulus amebocyte lysate microassay. The limit of sensitivity of the assay was 0.01 ng/ml. All specimens that were positive for endotoxinlike activity were subjected to confirmatory retesting, after which 38 (86%) remained positive. Comparison with available culture results revealed that 33 of 38 specimens (86%) were culture positive; 3 of the 5 culture-negative specimens were from patients on therapy for gram-negative becterial meningitis, and 1 was from a neonate. The overall specificity of confirmed positive tests was 99.5%, with a positive predictive value of 97.3%. There was one false-negative specimen, giving an overall sensitivity of 97.3% and a negative predictive value of 99.9%. Endotoxinlike activities of .150 ng/ml correlated with present illness of less than 2 days' duration (P = 0.024), elevated cerebrospinal fluid protein (P < 0.05), and seizures (P = 0.004); levels of .3,000 nglml correlated with neutropenia (P = 0.032), and levels of .3.2 x 106 ng/ml correlated with death (P = 0.001). We conclude that the Limulus amebocyte lysate microslide gelation test has prognostic value as a sensitive, specific, simple, inexpensive screening test for gram-negative bacterial meningitis.

H. influenzae b developed m e n i n g i t i s a f t e r 3 days. T h e s e 3 , and -6 p a t i e n t s with negative c u l t u r e s , were dropped from the study.All o t h e r p a t i e n t s did well and received X 15.7 days I V c e f o x i t i n before switching t o o r a l a n t i m i c r o b i a l s . Adverse r e a c t i o n s included a l l e r g i c rash ( I ) , m i l d e o s i n o p h i l i a ( 2 ) a n d m i l d e l e v a t i o n of SGOT ( 1 ) . C e f o x i t i n was discontinued f o r reason of t h e r a s h ; a l l o t h e r r e a c t i o n s resolved when t h e drug was d i s c o n t i n u e d a t t h e completion of therapy.Neutropenia (PMN <1000/mm3) was seen in 2 p a t i e n t s but resolved spontaneously. Urinary reducing substances were d e t e c t e d in 5 c a s e s (22%). Cefoxit in a m e a r s t o be s a t i s f a ct o r y i n i t i a l therapy f o r osteomyel i t i s and k i p t i c a r t h r i t i s in p e d i a t r i c p a t i e n t s ; i t should not be used f o r i n f a n t s <2 y e a r s of age where 5 influenzae b i s suspected, due t o t h e p o s s i b l e development of meningitis.ORAL RIFAMPIN/TOPICAL BACITRACIN THERAPY ASANADJUNC-Keenan, G . Randall Andrew~. Dagmar A. Schnader, Robert E. Fleming and Cindy A. S l a t e n , S t . L o u i s U n i v e r s i t y , S t . L o u i s U n i v e r s i t y School of Medicine, Cardinal Glennon Memorial Hospital f o r Children. Department of ~e d i a t r i c s /~d o l e s c e n t Medicine, S t . Louis, MO. Several months a f t e r i n s t i t u t i o n of i n t e n s i v e i n f e c t i o n c o n t r o l measures in a neonatal i n t e n s i v e c a r e u n i t with a high i n f e c t i o n r a t e due t o m e t h i c i l l i n -r e s i s t a n t S. aureus (MRS), p a t i e n t s and personnel colonized with t h e~r~a n i s m~e t a t e d with rifampin ( R ) , b a c i t r a c i n (6) and hexachloraphene (H) in an attempt t o reduce t h e r e s e r v o i r of MRS. I n f e c t i o n r a t e s in t h e 6 months p r i o r t o t h e treatment (Rx) period were 11-22% and c o l o n i z a t i o n r a t e s ranged from 26-49%. 1 6 p a t i e n t s colonized with MRS i n n o s e , cord o r t r a c h e a and 5 personnel colonized i n t r a n a s a l l y w e r e included in t h e study. P a t i e n t s i t e s of MRS c o l o n i z a t i o n s includednose-4, cord-2, nose and cord-6, nose and trachea-4. Rx regimen included RZOmg/kg/day x5 days, B ointment t o nose, c o r d , tracheostomy s i t e x 6 d a i l y and H bath with r i n s e d a i l y x 2 days. Personnel received R 600 mg/day x5 days and B ointment i n t r a n a s a l l y 6x d a i l y . Repeat c u l t u r e s showed no MRS c o l o n i z a t i o n in 9/16 (56%) p a t i e n t s and 5/5 personnel 2-8 weeks a f t e r Rx. F a i l u r e o f Rx was not s t a t i s t i c a l l y a s s o c i a t e d with any p a r t i c u l a r s i t e ( s ) of c o l o n i z a t i o n . Adverse r e a c t i o n s t o Rx included vomiting (3/16) and t r a n s i e n t hypertransaminasemia (2/16). Previous studies of influenza A inf...

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...