SUBGROUPS OF LEGIONELLA PNEUMOPHILA SEROGROUP 1

1088

Samples with high haemorrhagic potential (including LMW heparin samples that caused clinical bleeding)3 also had the highest degree of relative intensity of the NMR extra signals (table i). Some of these extra signals were associated with the presence of EDTA (ethylenediamine tetra-acetic acid). EDTA was present in various salt forms at concentrations ranging from 0 05 to 2 % in the heparin preparations we used for animal experiments. Addition of EDTA to a typical preparation of unfractionated pig mucosal heparin (PM-IF significantly prolonged the template bleeding time in rats (table n). By contrast sodium or calcium EDTA alone or added to extensively dialysed heparin samples) did not modify the bleeding time significantly. These results suggest that specific contaminants may be responsible for the unusually high haemorrhagic potential expressed by some heparin preparations, possibly by interfering with one or more mechanisms of primary haemostasis. Work is in progress to find out if EDTA plays a major part in this heparin effect or merely accompanies other bleeding factors and to see if some heparins have discriminants that make them susceptible to this

and she removed the dressing 24 h later. No blistering occurred and the skin has remained normal. Clobetasol is a powerful cutaneous vasoconstrictor but its exact mechanism of action is unknown.2 This ointment deserves a place in the first-aid treatment of bums but early application is necessary, within minutes of burning, before blistering can take place. Application of this steroid to blistered skin could theoretically

predispose to sepsis. While our patient did not immerse her hand in cold running water we would not denigrate this well-established first-aid measure. Perhaps it should be recommended while someone goes to find the clobetasol. T. C. HINDSON M.HAZELL L. WICKRAMASINGHE

Dermatology Department, Royal Infirmary, Sunderland SR2 7JE 1. Hindson TC,

Spiro J, Downey A. PUVA therapy of chronic actinic dermatitis. Br J Dermatol 1985; 113: 157-60. 2. Hindson TC, Spiro J, Scott LV. Clobetasol propionate ointment reduces inflammation after cryotherapy. Br J Dermatol 1985; 112: 599-602.

EDTA effect. BLEEDING ASSOCIATED WITH HEPARIN CONTAMINANTS

BENITO CASU ANNAMARIA NAGGI

SIR,-Although heparin-related haemorrhage1 has long been thought of as intrinsically associated with the anticoagulant properties of the drug, some heparin fractions with low anticoagulant activity have been reported to induce bleeding.2-6 These observations support the concept> that at least part of the bleeding caused by heparin is related to structural features or components of the polysaccharide not necessarily involved in the expression of its anticoagulant properties. Several preparations of commercial heparin and heparin fractions from different manufacturers, and some of the corresponding low-molecular-weight (LMW) fractions, prepared by fractionation with ethanols were analysed by 13C-NMR (nuclear-magnetic resonance) spectroscopy,7,8 While unfractionated heparins expressed an anticoagulant activity within the normal range, the corresponding LMW fractions had, as expected,9 lower activity (data not shown). The bleeding potential of the same heparins was tested by measuring template bleeding times in the rat taih° 15 min after intravenous administration of 0-75 mg/kg bodyweight of the drugs. The response in this animal model is relatively independent of coagulation, and reflects effects on primary haemostasis.10 Besides major signals associated with known sequences of the regular and irregular regions ofheparin8 (with relative intensities as in typical preparations of pig mucosal heparins)the preparations display 13 C-NMR "extra signals" of variable intensity in the 81-86 and 53-66 ppm regions. The extra signals are also seen, sometimes more strongly in LMW fractions. At least in one case, components giving rise to these signals could be largely removed by precipitation in the presence of 10% calcium chloride, whereas all the heparin species remained in solution. TABLE I-PROLONGATION OF TEMPLATE BLEEDING TIME IN RATS AND INTENSITY OF NMR EXTRA SIGNALS

p<001. Numbers refer bleeding time.

to

number of

heparms

and

heparin fractions causing

a

prolongation

of

TABLE II-EFFECT OF ADDITION OF EDTA TO UNFRACTIONATED PIG MUCOSAL HEPARIN ON NMR EXTRA SIGNALS AND ON

TEMPLATE BLEEDING TIME I

*p < 0-0 (Dunnet test).

I

j

I

s

G. Ronzoni Institute, 20133 Milan, Italy

PASQUA ORESTE GIANGIACOMO TORRI

JERTA PANGRAZZJ M. Negri Institute, Milan

ANTONIO MAGGI MARZIA ABBADINI MARIA BENEDETTA DONATI

Jaques L. Heparins: Anionic polyelectrolyte drugs. Pharmacol Rev 1980; 31: 99-166. S, Pelissier E, Dreyfus G, et al. Low-molecular weight heparin in extracorporeal circulation. Lancet 1984; i: 1182. 3. Schmitz-Huebner M, Bunte H, Freise G, et al. Clinical efficacy of low molecular weight heparin in postoperative thrombosis prophylaxis. Wochenschr 1984; 62: 1.

2. Massonnet-Castel

349-53.

Pangrazzi J, Abbadini M, Zametta M, Casu B, Donati MB. Low molecular weight heparins and bleeding. Thromb Haemost 1985; 51: 158. 5. Pangrazzi J, Abbadini M, Zametta M, et al. Antithrombotic and bleeding effects of a low-molecular weight heparin fraction. Biochem Pharmacol 1985; 34: 3305-08. 6. Hirsh J. In vivo effects of low molecular weight heparins on experimental thrombosis and bleeding. Haemostasis 1986; 16: 82-86. 7. Casu B, Johnson EA, Mantovani A, et al. Correlation between structure, fat-clearing alnd anticoagulant properties of heparins and heparan sulphates. Arzneim-Forsch 1983; 33: 135-42. 8. Casu B. Structure and biological activity of heparin. Adv Carbohydr Chem Biochem 1985; 43: 51-134. 9. Barrocliffe TW, Johnson EA, Eggleton CA, Kemball-Cook G, Thomas DP. Anticoagulant activities of high and low molecular weight heparin fractions. Br J Haematol 1979; 41: 573-83. 10. Dejana E, Villa S, de Gaetano G. Bleeding time in rats: A comparison of different experimental conditions. Thromb Haemost 1982; 48: 108-11. 4.

SUBGROUPS OF LEGIONELLA PNEUMOPHILA SEROGROUP 1

SIR,-Legionella pneumophila serogroup 1 (SG1) is antigenically heterogeneous. The specificity of monoclonal antibodies, has led to the development of epidemiological marker or fingerprinting systems for SG isolates, which aids the identification of potential sources of infection in institutional or epidemic legionellosis. During a legionellosis outbreak, the strains of SG isolated from two patients in the Dennistoun district of Glasgow and from two samples from the evaporative condenser that was epidemiologically incriminated as the infecting source1 were all SG1 subgroup Pontiac la, when assayed by immunofluorescent tests with the Oxford panel of monoclonal antibodies.2 The Pontiac subgroup contains the main strains causing legionellosis outbreaks in Britain. This subgroup is the same as the earlier la subgroup of the Centres for Disease Control (CDC), which also contains most of the outbreak strains in the USA. In contrast, 16 strains of L pneumophila collected at the same time as the isolates from the Dennistoun outbreak from cooling towers or tap-water in six districts in or near the Glasgow area were in the OLDA or Bellingham subgroups of SG1 with the Oxford panel. 11 were OLDA 2a, 4 were OLDA la, and 1 was Bellingham. Although strains in these main subgroups may cause sporadic infections in susceptible individuals, they rarely cause outbreaks and they comprise 90% of SG strains found in environments unassociated with disease.4 The antigens detected by one of us (R.M.C.K.) in the

1089 RELATION BETWEEN L PNEUMOPHILA SGI MONOCLONAL PANELS

patients associated with the Dennistoun outbreak recognised by the CDC monoclonals MAB 1 and 2,3,5 which

urine of three were

those that react with Pontiac la strains. This indicates that all studied were infected with the same strain. The relation between the earlier CDC and Oxford panels and the "standardised" panel6 recommended after an inter-laboratory study and a more recent CDC panel is shown in the table. The SG1 strains that caused the Dennistoun outbreak belonged to the Benidorm subgroup of the standardised panel and to the MAB 12 subgroup of the more recent CDC panel. are

patients

We thank Houseman (Burnham) Ltd, Slough, for allowing us to subgroup of the environmental strains that they had found in the Glasgow area at the time of the outbreak. some

Public Health Laboratory, John Radcliffe Hospital, Oxford

J. O’H.

TOBIN

Division of Bacterial Diseases, Centers for Disease Control, Atlanta, Georgia, USA

R. M. MCKINNEY

Department of Laboratory Medicine, Ruchill Hospital, Glasgow G20 9NB

R.

J. FALLON

1. Ad Hoc Committee. Outbreak of legionellosis in a community. Lancet 1986; ii: 380-83. 2. Watkins ID, Tobin JO’H, Dennis PJ, Brown W, Newham R, Kurtz JB. L pneumophila SG subgrouping by monoclonal antibodies: An epidemiological tool. Hyg Camb 1985; 95: 211-26. 3. McKinney RM, Thacker L, Wells DE, et al. Monoclonal antibodies to L pneunwphila SG1: Possible applications in diagnostic tests and epidemiologic studies. Zbl Bakt Hyg I Abt Ong A 1983; 255: 91-95. 4. Tobin JO’H, Watkins ID, Woodhead S, Mitchell RG. Epidemiological studies using monoclonal antibodies to L pneumophila serogroup 1. Israel I Med Sa 1986; 10: 711-14. 5. Selander RK, McKinney RM, Whittam TS, et al. Genetic structure of populations of L pneunwphila. _7 Bactenol 1985; 163: 1021-37. 6. Joly JR, McKinney RM, Tobin JO’H, Bibb WF, Watkms ID, Ramsay D. Development of a standardised subgrouping scheme for L preeumophila serogroup I 1. usmg monoclonal antibodies. Clm Microbiol 1986; 23: 768-71.

CENTRAL ANTICHOLINERGIC SYNDROME

StR,—Dr Hannington-Kiffs comments (April 11, p 862) on lack of awareness amongst anaesthetists of the central anticholinergic syndrome (CAS) are most pertinent, as the following case shows. A 65-year-old man in good general health but with a history of transient ischaemic attacks was prepared for surgery (hernia repair) with intramuscular morphine 10 mg and atropine 05 mg. His preoperative blood pressure was 130/80 mm Hg and pulse 90/min. After thiopentone 400 mg neuromuscular blockade was obtained with suxamethonium 50 mg and pancuronium 3 mg. Anaesthesia was maintained with 70 % nitrous oxide in oxygen plus halothane. The operation lasted 60 min and was uneventful. Reversal of neuromuscular blockade was with neostigmine 2-5 mg and atropine 1mg. Intramuscular morphine 15 mg was given postoperatively. Some hours later anaesthesia was again required for exploration of a wound haematoma. Premedication was with intramuscular papaveretum 20 mg, hyoscine 0-4 mg, and perphenazine 5 mg. The patient was reanaesthetised 5 h after the end of the first operation. Following etomidate 16 mg he was given suxamethonium 100 mg and atracurium 30 mg. Anaesthesia was maintained with 67% nitrous oxide in oxygen plus enflurane. During the operation the patient’s systolic pressure fell transiently to 60 mm Hg. The operation lasted 50 min and reversal of neuromuscular blockade

achieved with neostigmine 25 mg and atropine 1-25 mg. Spontaneous respiration was not resumed immediately but improved sufficiently after naloxone 0-8 mg to allow the patient to be extubated in the left lateral position. An oropharyngeal airway was inserted. One hour later the patient was still unrousable but had adequate respiratory excursions. Naloxone 0-4 mg had no effect on the patient’s mental state. 3 h after the end of the second operation the patient was still unconscious and in view of his history and the transient peroperative hypotension it was feared that he might have had a stroke. The duty consultant was contacted and the anaesthetic history was reviewed. The patient responded only to painful stimulation. His blood pressure was 130/80 mm Hg and pulse 130/min. The skin was warm and dry and his axillary temperature 37-5OC. There were no focal neurological signs but the pupils were dilated. A diagnosis of CAS was suggested and physostigmine salicylate 1 mg was slowly injected intravenously. Within 2 min the patient regained full consciousness. He remained sleepy for several hours but was easily rousable. The rest of his hospital recovery was uneventful. There were no residual problems on follow-up. The lesson from this case is clear. Repeated administration, or high doses, of centrally acting anticholinergic agents may be hazardous, especially in the elderly. Anaesthetists should be aware was

of the CAS and its treatment.! Because of the short duration of

action, injections of physostigmine may have to be repeated and its is not without hazard. Hence avoidance is better than cure and the trends away from anticholinergic premedication and for the greater use ofglycopyrronium bromide in anaesthetic practice are to be encouraged. use

Department of Anaesthesia, University of Manchester, University Hospital of South Manchester, Manchester M20 8LR 1. Duvoisin RC, Katz R. Reversal of central

M. BEECH C. HELL P. NIGHTINGALE

anticholinergic syndrome physostigmine. JAMA 1968; 206: 1963-65.

in

man

by

FATAL RHABDOMYOLYSIS IN MARATHON RUNNER

SIR,-Dr Lonka and Dr Pedersen (April 11, p 857) report an tragedy. In such emergencies several opportunities for

uncommon

investigation are often lost. Poliomyelitis used to be most severe in those who had indulged in various activities while incubating the infection and there have been occasional deaths from influenza shortly after indulging in sports. Might this marathon runner have been incubating a viral infection? Viruses that may cause myositis (as distinct from myalgia) include, besides echoviruses,’-’, adenoviruses, Coxsackie viruses, Epstein-Barr virus, herpesviruses, and influenza B viruses. Mild damage might be aggravated by a marathon run and many such infections could be asymptomatic in a physically fit person until overexertion occurs. Disseminated intravascular coagulation (DIC) could be a consequence of the extensive rhabdomyolysis, as Lonka and Pedersen state, but DIC has been associated with viral infections.’-6 Some of these tragedies may be associated with a subclinical viral infection which gets an opportunity to create severe havoc because of, strenuous exercise taken at the wrong moment-perhaps to "fight off a cold that is coming on" or because it had become routine to go for a run. Brownlee

Laboratory, Hospital, Glasgow G20 9NB; and Pathology Department, Western Infirmary, Glasgow Ruchill

JAMES F. BOYD

JM, van Scoy R, McKenna CH, et al. Echovirus polymyositis in patients hypogammaglobulinemia. Am J Med 1986; 81: 35. 2. Josselson J, Pula T, Sadler JH. Acute rhabdomyolysis associated with an echovirus 9 1. Crennan

with

infection. Arch Intern Med 1980; 140: 1671. PJ, Ochs HD, Corey L, et a1. Echovitus encephalomyelitis/myositis in X-linked agammaglobulinemia. N Engl J Med 1985; 313: 758. 4. Davison AM, Thomson D, Robson JS. Intravascular coagulation complicating influenza A virus infection. Br Med J 1973; 1: 654. 5. Luksza AR, Jones DK. Influenza B virus infection complicated by pneumonia, acute renal failure and disseminated intravascular coagulation. J Infect 1984; 9: 174. 6. Settergren B, Norrby R, Naslund U, et al. Case of epidemic nephropathy associated with disseminated intravascular coagulation. Lancet 1983; ii: 1419. 3. Mease