FIS 99 Abstracts

ORAL PRESENTATIONS

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VANCOMYCIN-INTERMEDIATESTAPHYLOCOCCUS AUREUS AT A SCOTTISHHOSPITAL. John Hood’, Giles F S Edwards’,Bonn ie Cosgrove2,Morrison*,

Evonne Curran’, Donald

Department’Curtis G Gernmell’. Bacteriology

and Scottish MRSA ReferenceLabo+or$, Glasgow Royal Infirmary, Glasgow.

We report two cases of MRSA with vancomycin-intermediate resistance (VISA), defined as strains withvancomycin MIC >Smg/L. To date only six such caseshave been reported world-wide. In all previous cases VISAwere iso la ted fo l lowing pro longed t rea tment w i thvancomycin. In contrast, the present cases were notexposed to vancomycin but were detected by the ScottishM R S A R e f e r e n c e L a b o r a t o r y ( S M R S A R L ) V I S Ascreening program. Between February 1998 and May 1999t h e S M R S A R L s c r e e n e d 7 9 2 3 M R S A , i n c l u d i n g 5 8 7 7( 7 4 % ) EMRSAIS a n d 1 5 6 8 ( 2 0 % ) E M R S A 1 6 . In M a y o fthis year two MRSA isolated from two patients at GlasgowR o y a l I n f i r m a r y w e r e i d e n t i f i e d a s V I S A . T h e s e w e r eunrelated by molecular (PFGE) typing and were confirmedas V ISA by the Ant ib io t ic Res is tance Mon i to r ing &R e f e r e n c e L a b o r a t o r y , C P H L , L o n d o n . O n e i s o l a t e(SMI09a) had vancomycin MIC=Smg/L and teicoplaninMIC=Smg/L. It was resistant to erythromycin, gentamicin,ciprotloxacin, trimethroprim, tetracycline and kanamycin.The second isolate (SM99a) had vancomycin MIC=6mg/Land te icop lan in MIC=4mg/L. I t w a s r e s i s t a n t t oerythromycin, clindamycin, gentamicin, ciprofloxacin,tetracycline, kanamycin and rifampicin.

w o 3UNDISCOVERED HEPATITIS B TRANSMISSIONFROM AN HEPATITIS B E ANTIGEN POSITIVESURGEON TO HIS PATIENTS OVER A FOUR-YEARPERIODI . J . B . S p i j k e r m a n ’ , G . Weers-Pothof?, R . A . Couth&o’.Division Public Health and Environment, GG&GD,Amsterdam, the Netherlands’, Med. Microbial. Lab.,B o s c h M e d i s c h Centrum, D e n B o s c h * ,

Three cases of acute hepatitis B were reported at aregional health service; all patients were operated on athospital A by the same general surgeonThe surgeon (X)was found to be HbsAg- and HbeAg-positive with a viralload of >5x109 copies/ml. A retrospective cohort studywas conducted on 1562 patients on whom surgeon X hadoperated from June 1995 through February 1999.Moreover, a case-control study was carried out to studyrisk factors for HBV transmission. Surgeon X transmittedHBV to 29 patients (1.9 %), of whom 2 remained HBVcarriers. In addition, one case of secondary tramnissionwas identified, in which the patient died from fulminanthepatitis B infection. DNA sequences obtained fromsurgeon X were 100% identical to sequences in 7 of the 29cases and in the case of secondary transmission. SurgeonX was a non-responder after HBV vaccination andappeared to be infected for more than 10 years. At least I1patients were infected during ‘low risk’ procedures.Transmission from surgeon to patients can occur withoutdiscovery for a long period of time. Prevention requires amore stringent policy for the vaccination and testing ofsurgeons. It may require revision of policies allowingsurgeons to perform “non-exposure prone” procedures,since these are not without risk of HBV transmission.

w o 2

THE E F F I C A C Y O F POLYSACCI-IARIDEPNEUMOCOCCAL VACCINE REVISITED: META-ANALYSIS OF RANDOM&ED TRIALS AND RE-EVALUATION OF THE CASE-CONTROL STUDIEST.E.A. Peto and B.A. Lipsky, Nuffield Department ofMedicine, John Radcliffe Hospital, Oxford OX3 9DU.

Pneumococcal vaccination is widelyrecommended. Evidence of efficacy was based on resultsof early randomised controlled trials in South Africa andfrom standard case-control studies in the US. In additionefficacy was demonstrated indirectly bv comparing thedistribution of pnemnococcal serotypes recovered -fromvaccinated and non-vaccinated individuals in the US.However, recent randomised controlled trials havesurprisingly failed to demonstrate vaccine efficacy.Possible reasons for these discrepancies are presented.

A meta-analysis of all randomised studies(published and unpublished) shows no clear evidence ofany clinical benefit from vaccination. A critical re-evaluation of the published case-control data wasundertaken which suggested that poor matching mightaccount for some of the apparent clinical benefit fromvaccination. However, the apparent efficacy showed inthe South African trials and by the results from theindirect methods in the US cannot easily be explainedstatistically.

One possible explanation for these discrepanciesis that the vaccine serotypes (the more commonserotypes) @e rise to different patterns of clinicaldisease compared to the non-vaccine serotypes Suchdifferences might be relevant to the design andinterpretation of current studies assessing the newerconjugate pneumococcal vaccines,

w o 4

LungfunclionteslsaRervaricellapn~~apmspecbivestudyA H Mdm’z Ptatigna&,L Maucckr, MW McKaxlr&.@&nmt of

l&ticm’Re@a&Futr&nUni?RoyalHallan&iieHu@al,Sha5ekl

lntruduction: The irxihce of chicken pox in adults has doubled overthelasttwodccadesinE@landandWaJcs Liltledataisavailableonlung futaion in ptimts mvd Gum chicken pox pnarmoniaChanges of lung fun&n alter bactaial pnannonia include restridiveven&ciydefi~iIlstaticlllngvolumesandltmgdiffusicplcapzil~thesechat~inlungfundionn~ylastfziflZ.MeUlods: Pat&s admitted with chicken pox wcm it&ded ifthey hadnohistoty0f1ungdcelxrzvi~pl~ cuni~labolatoIyaudcpidenliological were data collected; p&zlts had spitcmeby anddi8iionstudiedat&&uge,2montlisatidevety3n~mthun!iltmmlhtialor I-yearhadelapscd Resul~wercconsidcmdabnormaliftbey~~de 8@%ofeqxztedvalu.Results:37patiaus(12~m)wererecruitedtothestudy29hadcl~syml+nsona&nis&and18hsdpneumomti$abmmmalCXR). FVCncmuked in all followed patients (39. FEVl was matgimly abnonmlin 3 patients at one year. TLC0 lva.5 rbmmlal in 31/37 (84%) al&chatge(avemgetcd&onof42.4%);5pahentsteacl&ncxmalvnktesin the followi& 12 months. In loill (92%) ofpitients with pneumomtisIinishd 1 l/12 F/u; the avcmge ted&ion ofTLC0 mached plateau aller5 mmhs with levels of 3639% (SD 8%) of expeckd values. 5 patie&hnishcd 15/12allwemal;rrarnsl(avemgetedu&n38?/~SD6%)CondllsiomtheprttemofRFTsabmRmalityinchichenpoxdiIkmjficmthatcau&bybac&alpllRnnonia Transfa Ibc& was sig&antlyreducedat12~~postinfedionin92%of~~~~~i~audloo ofpalientsat15mcntllssuggestingu~chic~poxcauselongtcnnltmgd@lncfion