- Email: [email protected]
RANITIDINE AND MENTAL CONFUSION
1303
MOSQUITO’S SECOND BITE? SIR,-Dr Smeaton, Slater, and Dr Robson (April 14, p 845) reported a case of falciparum malaria probably contracted on board an Ethiopian Airways flight from London (Heathrow) to Rome. Dr Robson has kindly informed us that the patient travelled on an evening flight on June 11, 1983. We have ascertained that another case of falciparum malaria occurred in somebody else who had also travelled on the same flight. It seems most likely that both infections were transmitted by the same "commuter" anopheline mosquito which had been in the aeroplane since it left Africa and which bit both patients while they were en route from Heathrow to Rome. Mosquitoes will bite a second time if disturbed during a blood feed.2 In addition to these two cases associated with London (Heathrow) airport, involving patients resident in London and3 Stanley in Durham, two additional cases of "airport malaria"3 appear to have occurred in the summer of 1983 in people living 10 km and 15 km south-west of Gatwick airport in Sussex4(and D. Whitfield and others, unpublished). None of these four patients had A COMMUTER
Dr
Electron micrographs of parietal cells from saline (a) or propranolol (b).
rats
given physiological
Note stimulated appearance with extensive intracellular canalicular system N = nucleus. (x 4800.)
(SC) in (b). M=mitochondnon,
interpret in clinical terms. However, further studies concerning the influence of chronic 0-blocker treatment on gastric mucosal morphology and function are warranted. ROGER HENRIKSSON
Departments of Histology and
Anatomy, University of Umeå, S-901 87 Umeå, Sweden
BJÖRN ZACHRISSON HÅKAN BLOM
in your issue of May 12 (p 1071) describe two with ranitidine who had experienced mental confusion. The conclusion that these events are causally related is, however, not substantiated by the clinical information presented. There is little evidence in the case reported by Dr Silverstone to suggest the episode was drug induced. Confusion is not uncommon in patients with alcoholic cirrhosis. Hepatic encephalopathy due to causes other than gastrointestinal bleeding may have been responsible for her deterioration in mental state. Alternatively, the symptoms described are also consistent with a diagnosis of delirium tremens. The temporal improvement in the patient’s mental status makes the proposed diagnosis of a drug-induced event unlikely. Dr Epstein reports mental confusion in an 87-year-old man with myeloma, hepatoma, cerebral atrophy, and other neurological symptoms of indeterminate origin. These disorders and the coprescription of centrally acting drugs are alternative factors which may have been responsible for the confusional state.
SIR,-Letters
on treatment
Liver Unit, King’s College Hospital, London SE5 8RX
For details of cases in Sussex, London, and Durham respectively, we thank Dr D. Whitfield (Crawley General Hospital), Dr W. Weir (Coppetts Wood Hospital), and Dr P. Robson (Shotley Bridge General Hospital). We also thank the patients who have given us detailed information. PHLS Malaria Reference Laboratory and Department of Entomology, London School of Hygiene and Tropical Medicine,
AMODIAQUINE AND CHLOROQUINE EFFICACY AGAINST PLASMODIUM FALCIPARUM IN MADAGASCAR
SiR,—Dr Spencer and colleagues (April 28, p 956) found amodiaquine more effective than chloroquine against Plasmodium falciparum in an area oflimited chloroquine resistance. We obtained similar results in 1983 in Madagascar, where chloroquine resistance 7
emerging. 6,
is
360 patients with P falciparum infection were treated with chloroquine or amodiaquine at 10 mg/kg in a single dose or 25 mg/kg over
J. E.
3
1. Weir
2 3. 4 5 6.
7
HEGARTY
D. C. WARHURST C. F. CURTIS G. B. WHITE
London WCIE 7HT
STEN HELLSTRÖM
RANITIDINE AND MENTAL CONFUSION
patients
visited countries where malaria transmission occurs, whereas more than two thousand additional cases of imported malaria were diagnosed in UK during 1983 in patients who had apparently become infected abroad. It was tentatively concluded that the two cases associated with Gatwick airport were probably the victims of an infective mosquito which had escaped from an aeroplane after being accidentally brought from a malarious tropical country. The importance of spraying aircraft with adequate amounts of insecticide on take-off from a malarious zone is emphasised: 280 g of fast-acting pyrethroid insecticide (ie, seven aerosol canisters) are needed for a Boeing 747 passenger cabin. Curtis and Whitereport that live mosquitoes from Africa were present in some passenger aeroplanes on arrival at Gatwick and that when the two cases of malaria transmission occurred locally in July, 1983, it was an exceptionally warm month when tropical mosquitoes would be more likely to fly out of aeroplanes and disperse locally. Until 1983 the last two cases of malaria transmission in the UK were of P vivax in Lambeth (south London) in 1953.5 Clinicians must be prepared for further airport malaria cases this summer. Diagnosis is vital since untreated falciparum malaria can be fatal.
days
and followed up for
at
least 7
days.
In vitro semi-
WRC, Hedges J, Wright J, Higgins A, Corringham R Atypical falciparum malaria. Br Med J (in press). Boreham PFL Some applications of bloodmeal identification in relation to the Med Hyg 1975; 78: 83-91 epidemiology of vector borne diseases. Trop J Holvoet G, Michielsen P, Vandepitte J. Airport malaria in Belgium. Lancet 1982; ii: 881-82. Curtis CF, White GB Plasmadium falciparum transmission in England: entomological and epidemiological data relative to cases m 1983. J Trop Med Hyg (in press). Shute PG. Indigenous P vivax malaria in London believed to have been transmitted by Anopheles plumbeus Mon Bull Min Health Publ Health Lab Serv 1954; 13: 48. Arronson B, Bengtsson E, Bjorkman A, Pehrson PO, Rombo L, Wahlgren P. Chloroquine resistant falciparum malaria in Madagascar and Kenya. Ann Trop Med Parasit 1981; 75: 367-73. Le Bras J, Dulat C, Coulanges P, Ralamboson D, Rakotonirima PJ, Deloron P. Etude préliminaire in vitro de la chimiosensiblité de Plasmodium falciparum à Madagascar. Arch Inst Pasteur Madagascar 1982; 50: 15-22.
MOSQUITO’S SECOND BITE? SIR,-Dr Smeaton, Slater, and Dr Robson (April 14, p 845) reported a case of falciparum malaria probably contracted on board an Ethiopian Airways flight from London (Heathrow) to Rome. Dr Robson has kindly informed us that the patient travelled on an evening flight on June 11, 1983. We have ascertained that another case of falciparum malaria occurred in somebody else who had also travelled on the same flight. It seems most likely that both infections were transmitted by the same "commuter" anopheline mosquito which had been in the aeroplane since it left Africa and which bit both patients while they were en route from Heathrow to Rome. Mosquitoes will bite a second time if disturbed during a blood feed.2 In addition to these two cases associated with London (Heathrow) airport, involving patients resident in London and3 Stanley in Durham, two additional cases of "airport malaria"3 appear to have occurred in the summer of 1983 in people living 10 km and 15 km south-west of Gatwick airport in Sussex4(and D. Whitfield and others, unpublished). None of these four patients had A COMMUTER
Dr
Electron micrographs of parietal cells from saline (a) or propranolol (b).
rats
given physiological
Note stimulated appearance with extensive intracellular canalicular system N = nucleus. (x 4800.)
(SC) in (b). M=mitochondnon,
interpret in clinical terms. However, further studies concerning the influence of chronic 0-blocker treatment on gastric mucosal morphology and function are warranted. ROGER HENRIKSSON
Departments of Histology and
Anatomy, University of Umeå, S-901 87 Umeå, Sweden
BJÖRN ZACHRISSON HÅKAN BLOM
in your issue of May 12 (p 1071) describe two with ranitidine who had experienced mental confusion. The conclusion that these events are causally related is, however, not substantiated by the clinical information presented. There is little evidence in the case reported by Dr Silverstone to suggest the episode was drug induced. Confusion is not uncommon in patients with alcoholic cirrhosis. Hepatic encephalopathy due to causes other than gastrointestinal bleeding may have been responsible for her deterioration in mental state. Alternatively, the symptoms described are also consistent with a diagnosis of delirium tremens. The temporal improvement in the patient’s mental status makes the proposed diagnosis of a drug-induced event unlikely. Dr Epstein reports mental confusion in an 87-year-old man with myeloma, hepatoma, cerebral atrophy, and other neurological symptoms of indeterminate origin. These disorders and the coprescription of centrally acting drugs are alternative factors which may have been responsible for the confusional state.
SIR,-Letters
on treatment
Liver Unit, King’s College Hospital, London SE5 8RX
For details of cases in Sussex, London, and Durham respectively, we thank Dr D. Whitfield (Crawley General Hospital), Dr W. Weir (Coppetts Wood Hospital), and Dr P. Robson (Shotley Bridge General Hospital). We also thank the patients who have given us detailed information. PHLS Malaria Reference Laboratory and Department of Entomology, London School of Hygiene and Tropical Medicine,
AMODIAQUINE AND CHLOROQUINE EFFICACY AGAINST PLASMODIUM FALCIPARUM IN MADAGASCAR
SiR,—Dr Spencer and colleagues (April 28, p 956) found amodiaquine more effective than chloroquine against Plasmodium falciparum in an area oflimited chloroquine resistance. We obtained similar results in 1983 in Madagascar, where chloroquine resistance 7
emerging. 6,
is
360 patients with P falciparum infection were treated with chloroquine or amodiaquine at 10 mg/kg in a single dose or 25 mg/kg over
J. E.
3
1. Weir
2 3. 4 5 6.
7
HEGARTY
D. C. WARHURST C. F. CURTIS G. B. WHITE
London WCIE 7HT
STEN HELLSTRÖM
RANITIDINE AND MENTAL CONFUSION
patients
visited countries where malaria transmission occurs, whereas more than two thousand additional cases of imported malaria were diagnosed in UK during 1983 in patients who had apparently become infected abroad. It was tentatively concluded that the two cases associated with Gatwick airport were probably the victims of an infective mosquito which had escaped from an aeroplane after being accidentally brought from a malarious tropical country. The importance of spraying aircraft with adequate amounts of insecticide on take-off from a malarious zone is emphasised: 280 g of fast-acting pyrethroid insecticide (ie, seven aerosol canisters) are needed for a Boeing 747 passenger cabin. Curtis and Whitereport that live mosquitoes from Africa were present in some passenger aeroplanes on arrival at Gatwick and that when the two cases of malaria transmission occurred locally in July, 1983, it was an exceptionally warm month when tropical mosquitoes would be more likely to fly out of aeroplanes and disperse locally. Until 1983 the last two cases of malaria transmission in the UK were of P vivax in Lambeth (south London) in 1953.5 Clinicians must be prepared for further airport malaria cases this summer. Diagnosis is vital since untreated falciparum malaria can be fatal.
days
and followed up for
at
least 7
days.
In vitro semi-
WRC, Hedges J, Wright J, Higgins A, Corringham R Atypical falciparum malaria. Br Med J (in press). Boreham PFL Some applications of bloodmeal identification in relation to the Med Hyg 1975; 78: 83-91 epidemiology of vector borne diseases. Trop J Holvoet G, Michielsen P, Vandepitte J. Airport malaria in Belgium. Lancet 1982; ii: 881-82. Curtis CF, White GB Plasmadium falciparum transmission in England: entomological and epidemiological data relative to cases m 1983. J Trop Med Hyg (in press). Shute PG. Indigenous P vivax malaria in London believed to have been transmitted by Anopheles plumbeus Mon Bull Min Health Publ Health Lab Serv 1954; 13: 48. Arronson B, Bengtsson E, Bjorkman A, Pehrson PO, Rombo L, Wahlgren P. Chloroquine resistant falciparum malaria in Madagascar and Kenya. Ann Trop Med Parasit 1981; 75: 367-73. Le Bras J, Dulat C, Coulanges P, Ralamboson D, Rakotonirima PJ, Deloron P. Etude préliminaire in vitro de la chimiosensiblité de Plasmodium falciparum à Madagascar. Arch Inst Pasteur Madagascar 1982; 50: 15-22.