584
although
recurrent
tumour grew
tracheal obstruction did
occur
the patient had terminal cachexia and further treatment was not undertaken; otherwise it would have been possible to have restored full airway patency by insertion of additional stents above and below the original. We believe that endoscopic insertion of a covered expandable metal stent provides simple, effective palliation for large airway obstruction caused by both intraluminal and extraluminal tumour, and should help to avoid death by gradual asphyxia in patients with advanced tracheobronchial malignancy.
We thank Cook (Bloomington, Indiana, delivery of the covered expandable stent.
Is
REFERENCES
when
beyond the borders of the stent. By this time,
USA) for rapid construction
and
1. Hetzel MR, Nixon C, Edmonstone WM, et al. Laser therapy in 100 tracheobronchial tumours. Thorax 1985; 40: 341-45. 2. Schray MF, McDougall JC, Martinez A, et al. Management of malignant airway compromise with laser and low dose rate brachytherapy: the Mayo Clinic experience. Chest 1988; 93: 264-69. 3. Macha HN, Koch K, Stadler M, et al. New technique for treating occlusive and stenosing tumours of the trachea and main bronchi: endobronchial irradiation by high dose iridium-192 combined with laser canalisation. Thorax 1987; 42: 511-15. 4. Wallace MJ, Charnsangavej C, Ogawa K, et al. Tracheobronchial tree: expandable metallic stents used in experimental and clinical applications. Radiology 1986; 158: 309-12. 5. Simonds AK, Irving JD, Clarke SW, Dick R. Use of expandable metallic stents in the treatment of bronchial obstruction. Thorax 1989; 44: 680-81. 6. Westaby S, Jackson JW, Pearson FG. A bifurcated silicone rubber stent for relief of tracheobronchial obstruction. J Thorac Cardiovasc Surg 1982; 83: 414-17.
"Campylobacter upsaliensis" an unrecognised cause
of human diarrhoea?
For 3 years a filtration system for the isolation of "new" campylobacter was included in the culture protocol of 15 185 stool specimens. "C upsallensis" was isolated in 99 patients, C jejuni subsp doylei in 4, and C hyointestinalis in 2. "C upsaliensis" was the only organism isolated in 83 patients. Clinical information was available for 77 out of these 83 patients. 92% of the patients had diarrhoea; vomiting and fever were rare (14% and 7%, respectively); the onset was mostly sudden; and the symptoms usually lasted for less than a week. Gross or occult blood was present in a quarter of cases and neutrophils were detected in faecal smears in about a fifth. "C upsaliensis" may be an unrecognised and frequent cause of diarrhoea in man, and selective isolation media should be combined with non-selective isolation systems. Lancet 1990; 335: 584-86.
Introduction
Catalase-negative or catalase-weak (CNW) strains of campylobacter were first isolated from dogs, both with and without diarrhoea.1 DNA hybridisation studies showed that these strains were members of a previously undescribed Campylobacter sp. The name "C upsaliensis" was proposed for the CNW group.2 The role of this organism as a pathogen in man is controversial. Several groups have reported on the association of "C upsaliensis" with
diarrhoea3-{; and bacteraemia. We provide additional evidence about "C upsaliensis" and diarrhoea in man.
Materials and methods The campylobacter-selective media used routinely in our laboratory were: (i) BMV, a solid blood-based medium (Virion AG, Zurich), containing cefoperazone (30 mg/1), rifampicin (10 mg/1), and amphotericin B (2 mg/1), (ii) CCDA, a solid blood-free basal medium CDA (Oxoid CM739, Basingstoke, UK), containing cefoperazone (32 mg/1) ;9 and (iii) a semi-solid medium containing cefoperazone (30 mg/1) and trimethoprim (50 mg/1)." We also included a filtration systemll in which a cellulose triacetate membrane filter (diameter 47 mm) was placed on Mueller-Hinton agar (Oxoid) with 5% sheep blood prepared in small petri dishes. Initially, from July 1, 1986, to Jan 31, 1987, we used filters with a pore size of 0-65 (im (Gelman, Michigan); however, because of a high rate of contamination with faecal flora (12% of the plates), we decided to use 0 45 pm filters (Oxoid). Clinical data were collected retrospectively and prospectively. The appearance of the stools was noted, and the presence of leucocytes and erythrocytes in the stools was evaluated by Giemsa
stain.
ADDRESSES
WHO Collaborating Centre for Enteric Campylobacter, St Pieters University Hospital, Brussels (H. Goossens, MD, L. Vlaes, M. De Boeck, J. Levy, MD, P. De Mol, MD, Prof J.-P. Butzler, MD,); and Laboratory for Microbiology and Microbial Genetics, Rijksuniversiteit, Gent, Belgium (Prof K. Kersters, MD, B.Pot, BSc, P. Vandamme, BSc). Correspondence to Dr H. Goossens, Laboratorium voor Microbiologie, St Pieters University Hospital, 322 Hoogstraat, B-1000 Brussels, Belgium.
585
TABLE I-ISOLATION OF ENTERIC PATHOGENS FROM 15 185 STOOL SPECIMENS
TABLE II-IDENTIFICATION OF CAMPYLOBACTERS
Seasonal isolation of "C upsaliensis " from stool specimens. No of patients summed for each month, 1986-89
by sodium dodecyl sulphate/polyacrylamide gel electrophoresis of whole cell proteins."
Results I shows the frequency of isolation of the bacterial enteropathogens from all stool specimens. Out of 802 campylobacter isolates, 753 could be further identified (table II). Specimens containing less that 105 colony forming units of C jejuni or C coli per gram of faeces were found to be negative by the filter method (table III). We would expect a similar sensitivity for "C upsaliensis" since this organism has an identical size and morphology. 13 "C upsaliensis" was isolated in 56 patients during the first year of the study. During the second and third years "C upsaliensis" was isolated in 28 and 15 patients, respectively. Thus "C upsaliensis" was isolated in 99 patients. The seasonal isolation is shown in the figure. "C upsaliensis" was associated with other enteric pathogens in 16 out of these 99 patients (Giardia lamblia, 6 patients; rotavirus 3; S typhi, 2; Y enterocolitica, Cryptosporidium, adenovirus, S brandenburg, 1 each; and S sonnei with Entamoeba histolytica, 1). For the other 83 patients, clinical information was available for 77 (table IV). 73 patients were children (range,1 month to 5 years; mean, 17.7 months), and
Table
We tested 15 185 stool specimens from July 1, 1986 to June 30, 1989. All specimens were routinely processed to identify salmonellae, shigellae, Yersinia enterocolitica, and campylobacters. Selected stool specimens, including all those positive for "C upsaliensis", were also evaluated for the presence of intestinal protozoa, ova and larvae of helminths, rotavirus, and enteric adenovirus. All stool specimens were inoculated onto two solid selective media; the semi-solid medium was used for the final 4878 stool samples only. The specimens were incubated at 42-43°C in 84% N/10% COJ6% O2, The plates were examined for campylobacters 1 and 2 days later. The filtration system was tested on all stool specimens received in our laboratory. 6-8 drops of faecal suspension were placed on the surface of the filter. The filter was removed 30-60 min later. The petri dishes were incubated at 37°C under the same atmosphere as described before. Plates were examined daily for 3 days. To estimate the sensitivity of the filter method, for 2 months (Jan 2 to Feb 28, 1988) all stool specimens submitted to our laboratory for routine culturing were stored at 4°C until the campylobacter isolation procedure was finished. If stools were found positive for C jejuni, C coli, or C laridis,g of faeces was immediately suspended and further diluted in saline; these suspensions were inoculated onto BMV medium for colony counting. Suspected campylobacter colonies were stained with crystal violet. The oxidase and catalase tests were done, and all campylobacters isolated were biotyped.11 Campylobacter isolates that were catalase negative or weakly positive, or which could not be biotyped, were characterised phenotypically, and finally identified
4 were adults (22-64 years; 41 -8 years). 3 adults and 68 of the children had diarrhoea. 13 of these 77 patients received antibiotic therapy, (erythromycin, 11patients; amoxycillin,
2). The diarrhoeal symptoms disappeared with the eradication of the organisms in all 13 patients. Interestingly C jejuni subsp doylei could be isolated from the faeces of 4 children, all with diarrhoea. No other enteropathogens were isolated in their stools. Leucocytes TABLE IV-DETAILS OF 77 PATIENTS POSITIVE FOR "C UPSAUENSIS" " 0 N LY
TABLE III-SENSITIVITY OF FILTER METHOD
586
present in the stools of 2 of the 4 children. C hyointestinalis was isolated from 2 patients: from a child with typhoid fever and in an adult who had been admitted with abdominal pain, vomiting, nausea, fever, but no diarrhoea, and in whom endoscopy revealed a duodenal ulcer. were
Discussion In
our
study campylobacters
were
the
most
frequently
isolated enteric organism (58%). This high isolation rate for campylobacters may be explained partly by the routine use of a filter method. With this system we could increase the isolation rate for campylobacters by 19% which indicates that the use of selective isolation media is inadequate for the isolation of such species, especially for cephalothin-sensitive organisms such as C jejuni subsp doylei, C hyointestinalis, and "C upsaliensis".14 Unfortunately bacterial concentrations of less than 105 colony forming units per gram faeces cannot be detected with the filter method, which might explain why 14% of the antibiotic-resistant campylobacters, isolated by the classical method, had been missed with this system. It also indicates that we may expect an even higher isolation rate of "C upsaliensis" if a more sensitive detection system was available. Interestingly 20 C jejuni and 9 C coli were isolated with the filter method only. Ideally a selective isolation medium should be used in combination with the filter method for the recovery of campylobacters from stool specimens. We isolated "C upsaliensis" in 99 patients during the 3 year period. During the first year of study, "C upsaliensis" was isolated in 56 patients, which was more frequent than isolation of shigellae (49 patients) and Y enterocolitica (38). Clearly "C upsaliensis" had a high prevalence in the population studied. However, in the following 2 years of study, the number of "C upsaliensis" positive cases declined sharply (28 patients during the second year and 15 patients during the third). This may be due partly to the transfer, during the second half of 1986, of several paediatric units from our hospital to another hospital, outside the city centre. The high frequency of "C upsaliensis" may be explained by the large number of immigrants, mostly from Morocco and Turkey in our study population. During the summer many may return to their countries to visit family. The accompanying children are suddenly exposed to a new microbiological environment, usually with poor sanitary and over-crowded conditions. A late summer peak of C jejuni infections has been discussed,15 which might partly explain the high frequency of "C upsaliensis" from July to October. However, we are not able to explain the high frequency from November to January. In any case, this would suggest that "C upsaliensis" may be added to the list of enteric organisms responsible for traveller’s diarrhoea. Several groups have considered "C upsaliensis" as a cause of diarrhoea .4-5,7,16 There are several reasons why we believe that "C upsaliensis" can cause diarrhoea in man: (1) they were the only oganisms detected in 83 patients; (2) their presence in large numbers (greater than 105 colony forming units per gram faeces); (3) the presence of diarrhoea in 71 out of 77 patients where "C upsaliensis" was the only organism isolated; and (4) the eradication of the organism with disappearance of diarrhoeal symptoms after antibiotic therapy in all 13 patients treated. The onset of diarrhoeal disease was sudden and the disease was usually mild and lasted for less than a week.
C jejuni subsp doylei has been isolated from the gastric antral epithelia of adults17 and from the faeces of children with diarrhoea.18 The clinical significance of this new subspecies has not yet been established. We isolated Cjejuni subsp doylei as the single organism in 4 children, all with diarrhoea. This suggests that this organism might be pathogenic in man. We have no strong arguments to suggest that C hyointestinalis causes gastroenteritis, since in our first case this organism was isolated in a child with typhoid fever, and, in our second case, it was isolated in an adult with duodenal ulcer. We recommend that routine microbiology laboratories use a selective medium in combination with the filter method. This would significantly expand the genus Campylobacter. Continuing efforts should be made to develop new media for isolating "unusual" campylobacter and to defme additional phenotypic characteristics that may be exploited for identification and classification in the clinical laboratory.
REFERENCES 1. Sandstedt K, Ursing J, Walder M. Thermotolerant Campylobacter with no or weak catalase activity isolated from dogs. Curr Microbiol 1983; 8: 209-13. 2. Sandstedt K, Ursing J. Campylobacter upsaliensis, a new species, formerly the CNW group. XIV int congr Microbiology, Manchester, UK, Sept 7-13, 1986: 37. 3. Goossens H, De Boeck M, Coignau H, Vlaes L, Van den Borre C, Butzler JP. Modified selective medium for the isolation of Campylobacter spp from feces: comparison with Preston medium, a blood-free medium and a filtration system. J Clin Microbiol 1986; 24: 840-43. 4. Mégraud F, Bonnet F. Unusual Campylobacter in human feces. J Infect
1986; 12: 275-76. 5. Patton CM, Shaffer N, Edmonds
P, et al. Human disease associated with
"Campylobacter upsaliensis" (catalase-negative or weakly positive Campylobacter species) in the United States. J Clin Microbiol 1989; 27: 66-73. 6.
7.
Walmsley SL, Karmali MA. Direct isolation of atypical thermophilic Campylobacter species from human feces on selective agar medium. J Clin Microbiol 1989; 27: 688-70. Lastovica AJ, Le Roux E, Penner JL. "Campylobacter upsaliensis" isolated from blood cultures of pediatric patients. J Clin Microbiol 1989;
27: 657-9. 8. Goossens H, De Boeck
M, Butzler JP. A new selective medium for the isolation of Campylobacter jejuni from human feces. Eur J Clin Microbiol 1985; 2: 389-93. 9. Bolton FJ, Hutchinson DM, Coates D. Blood free selective medium for isolation of C jejuni from feces. J Clin Microbiol 1984; 19: 169-71. 10. Goossens H, Vlaes L, Galand I, Van den Borre C, Butzler JP. Semisolid blood free selective motility medium for the isolation of Campylobacter from stool specimens. J Clin Microbiol 1989; 27: 1077-80. 11. Steele TW, McDermott SN. The use of membrane filters applied directly to the surface of agar plates for the isolation of Campylobacter jejuni from feces. Pathology 1984; 16: 263-65. 12. Lior H. New extended biotyping scheme for Campylobacter jejuni, Campylobacter coli and "Campylobacter laridis". J Clin Microbiol 1984; 20: 636-40. 13. Goossens H, Pot B, Vlaes L, et al. Characterisation and description of "Campylobacter upsaliensis" isolated from human feces. J Clin Microbiol (in press). 14. Goossens H, Butzler JP. Isolation of Campylobacter upsaliensis from stool specimens. J Clin Microbiol 1989; 27: 2143-44. 15. Brasseur D, Casimir G, Goyens P. Campylobacter jejuni and infantile traveller’s diarrhoea. Eur J Pediatr 1986; 144: 517-18. 16. Taylor DE, Hiratsuka K, Mueller L. Isolation and characterization of catalase-negative and catalase weak strains of Campylobacter species, including "Campylobacter upsaliensis" from humans with gastroenteritis. J Clin Microbiol 1989; 27: 2042-45. 17. Kasper G, Dickgiesser N. Isolation from gastric epithelium of Campylobacter-like bacteria that are distinct from "Campylobacter pyloridis". Lancet 1985; i: 111-12. 18. Steele TW, Sangster N, Lanser JA. DNA relatedness and biochemical features of Campylobacter spp isolated in Central and South Australia. J Clin Microbiol 1985; 22: 71-74.
although
recurrent
tumour grew
tracheal obstruction did
occur
the patient had terminal cachexia and further treatment was not undertaken; otherwise it would have been possible to have restored full airway patency by insertion of additional stents above and below the original. We believe that endoscopic insertion of a covered expandable metal stent provides simple, effective palliation for large airway obstruction caused by both intraluminal and extraluminal tumour, and should help to avoid death by gradual asphyxia in patients with advanced tracheobronchial malignancy.
We thank Cook (Bloomington, Indiana, delivery of the covered expandable stent.
Is
REFERENCES
when
beyond the borders of the stent. By this time,
USA) for rapid construction
and
1. Hetzel MR, Nixon C, Edmonstone WM, et al. Laser therapy in 100 tracheobronchial tumours. Thorax 1985; 40: 341-45. 2. Schray MF, McDougall JC, Martinez A, et al. Management of malignant airway compromise with laser and low dose rate brachytherapy: the Mayo Clinic experience. Chest 1988; 93: 264-69. 3. Macha HN, Koch K, Stadler M, et al. New technique for treating occlusive and stenosing tumours of the trachea and main bronchi: endobronchial irradiation by high dose iridium-192 combined with laser canalisation. Thorax 1987; 42: 511-15. 4. Wallace MJ, Charnsangavej C, Ogawa K, et al. Tracheobronchial tree: expandable metallic stents used in experimental and clinical applications. Radiology 1986; 158: 309-12. 5. Simonds AK, Irving JD, Clarke SW, Dick R. Use of expandable metallic stents in the treatment of bronchial obstruction. Thorax 1989; 44: 680-81. 6. Westaby S, Jackson JW, Pearson FG. A bifurcated silicone rubber stent for relief of tracheobronchial obstruction. J Thorac Cardiovasc Surg 1982; 83: 414-17.
"Campylobacter upsaliensis" an unrecognised cause
of human diarrhoea?
For 3 years a filtration system for the isolation of "new" campylobacter was included in the culture protocol of 15 185 stool specimens. "C upsallensis" was isolated in 99 patients, C jejuni subsp doylei in 4, and C hyointestinalis in 2. "C upsaliensis" was the only organism isolated in 83 patients. Clinical information was available for 77 out of these 83 patients. 92% of the patients had diarrhoea; vomiting and fever were rare (14% and 7%, respectively); the onset was mostly sudden; and the symptoms usually lasted for less than a week. Gross or occult blood was present in a quarter of cases and neutrophils were detected in faecal smears in about a fifth. "C upsaliensis" may be an unrecognised and frequent cause of diarrhoea in man, and selective isolation media should be combined with non-selective isolation systems. Lancet 1990; 335: 584-86.
Introduction
Catalase-negative or catalase-weak (CNW) strains of campylobacter were first isolated from dogs, both with and without diarrhoea.1 DNA hybridisation studies showed that these strains were members of a previously undescribed Campylobacter sp. The name "C upsaliensis" was proposed for the CNW group.2 The role of this organism as a pathogen in man is controversial. Several groups have reported on the association of "C upsaliensis" with
diarrhoea3-{; and bacteraemia. We provide additional evidence about "C upsaliensis" and diarrhoea in man.
Materials and methods The campylobacter-selective media used routinely in our laboratory were: (i) BMV, a solid blood-based medium (Virion AG, Zurich), containing cefoperazone (30 mg/1), rifampicin (10 mg/1), and amphotericin B (2 mg/1), (ii) CCDA, a solid blood-free basal medium CDA (Oxoid CM739, Basingstoke, UK), containing cefoperazone (32 mg/1) ;9 and (iii) a semi-solid medium containing cefoperazone (30 mg/1) and trimethoprim (50 mg/1)." We also included a filtration systemll in which a cellulose triacetate membrane filter (diameter 47 mm) was placed on Mueller-Hinton agar (Oxoid) with 5% sheep blood prepared in small petri dishes. Initially, from July 1, 1986, to Jan 31, 1987, we used filters with a pore size of 0-65 (im (Gelman, Michigan); however, because of a high rate of contamination with faecal flora (12% of the plates), we decided to use 0 45 pm filters (Oxoid). Clinical data were collected retrospectively and prospectively. The appearance of the stools was noted, and the presence of leucocytes and erythrocytes in the stools was evaluated by Giemsa
stain.
ADDRESSES
WHO Collaborating Centre for Enteric Campylobacter, St Pieters University Hospital, Brussels (H. Goossens, MD, L. Vlaes, M. De Boeck, J. Levy, MD, P. De Mol, MD, Prof J.-P. Butzler, MD,); and Laboratory for Microbiology and Microbial Genetics, Rijksuniversiteit, Gent, Belgium (Prof K. Kersters, MD, B.Pot, BSc, P. Vandamme, BSc). Correspondence to Dr H. Goossens, Laboratorium voor Microbiologie, St Pieters University Hospital, 322 Hoogstraat, B-1000 Brussels, Belgium.
585
TABLE I-ISOLATION OF ENTERIC PATHOGENS FROM 15 185 STOOL SPECIMENS
TABLE II-IDENTIFICATION OF CAMPYLOBACTERS
Seasonal isolation of "C upsaliensis " from stool specimens. No of patients summed for each month, 1986-89
by sodium dodecyl sulphate/polyacrylamide gel electrophoresis of whole cell proteins."
Results I shows the frequency of isolation of the bacterial enteropathogens from all stool specimens. Out of 802 campylobacter isolates, 753 could be further identified (table II). Specimens containing less that 105 colony forming units of C jejuni or C coli per gram of faeces were found to be negative by the filter method (table III). We would expect a similar sensitivity for "C upsaliensis" since this organism has an identical size and morphology. 13 "C upsaliensis" was isolated in 56 patients during the first year of the study. During the second and third years "C upsaliensis" was isolated in 28 and 15 patients, respectively. Thus "C upsaliensis" was isolated in 99 patients. The seasonal isolation is shown in the figure. "C upsaliensis" was associated with other enteric pathogens in 16 out of these 99 patients (Giardia lamblia, 6 patients; rotavirus 3; S typhi, 2; Y enterocolitica, Cryptosporidium, adenovirus, S brandenburg, 1 each; and S sonnei with Entamoeba histolytica, 1). For the other 83 patients, clinical information was available for 77 (table IV). 73 patients were children (range,1 month to 5 years; mean, 17.7 months), and
Table
We tested 15 185 stool specimens from July 1, 1986 to June 30, 1989. All specimens were routinely processed to identify salmonellae, shigellae, Yersinia enterocolitica, and campylobacters. Selected stool specimens, including all those positive for "C upsaliensis", were also evaluated for the presence of intestinal protozoa, ova and larvae of helminths, rotavirus, and enteric adenovirus. All stool specimens were inoculated onto two solid selective media; the semi-solid medium was used for the final 4878 stool samples only. The specimens were incubated at 42-43°C in 84% N/10% COJ6% O2, The plates were examined for campylobacters 1 and 2 days later. The filtration system was tested on all stool specimens received in our laboratory. 6-8 drops of faecal suspension were placed on the surface of the filter. The filter was removed 30-60 min later. The petri dishes were incubated at 37°C under the same atmosphere as described before. Plates were examined daily for 3 days. To estimate the sensitivity of the filter method, for 2 months (Jan 2 to Feb 28, 1988) all stool specimens submitted to our laboratory for routine culturing were stored at 4°C until the campylobacter isolation procedure was finished. If stools were found positive for C jejuni, C coli, or C laridis,g of faeces was immediately suspended and further diluted in saline; these suspensions were inoculated onto BMV medium for colony counting. Suspected campylobacter colonies were stained with crystal violet. The oxidase and catalase tests were done, and all campylobacters isolated were biotyped.11 Campylobacter isolates that were catalase negative or weakly positive, or which could not be biotyped, were characterised phenotypically, and finally identified
4 were adults (22-64 years; 41 -8 years). 3 adults and 68 of the children had diarrhoea. 13 of these 77 patients received antibiotic therapy, (erythromycin, 11patients; amoxycillin,
2). The diarrhoeal symptoms disappeared with the eradication of the organisms in all 13 patients. Interestingly C jejuni subsp doylei could be isolated from the faeces of 4 children, all with diarrhoea. No other enteropathogens were isolated in their stools. Leucocytes TABLE IV-DETAILS OF 77 PATIENTS POSITIVE FOR "C UPSAUENSIS" " 0 N LY
TABLE III-SENSITIVITY OF FILTER METHOD
586
present in the stools of 2 of the 4 children. C hyointestinalis was isolated from 2 patients: from a child with typhoid fever and in an adult who had been admitted with abdominal pain, vomiting, nausea, fever, but no diarrhoea, and in whom endoscopy revealed a duodenal ulcer. were
Discussion In
our
study campylobacters
were
the
most
frequently
isolated enteric organism (58%). This high isolation rate for campylobacters may be explained partly by the routine use of a filter method. With this system we could increase the isolation rate for campylobacters by 19% which indicates that the use of selective isolation media is inadequate for the isolation of such species, especially for cephalothin-sensitive organisms such as C jejuni subsp doylei, C hyointestinalis, and "C upsaliensis".14 Unfortunately bacterial concentrations of less than 105 colony forming units per gram faeces cannot be detected with the filter method, which might explain why 14% of the antibiotic-resistant campylobacters, isolated by the classical method, had been missed with this system. It also indicates that we may expect an even higher isolation rate of "C upsaliensis" if a more sensitive detection system was available. Interestingly 20 C jejuni and 9 C coli were isolated with the filter method only. Ideally a selective isolation medium should be used in combination with the filter method for the recovery of campylobacters from stool specimens. We isolated "C upsaliensis" in 99 patients during the 3 year period. During the first year of study, "C upsaliensis" was isolated in 56 patients, which was more frequent than isolation of shigellae (49 patients) and Y enterocolitica (38). Clearly "C upsaliensis" had a high prevalence in the population studied. However, in the following 2 years of study, the number of "C upsaliensis" positive cases declined sharply (28 patients during the second year and 15 patients during the third). This may be due partly to the transfer, during the second half of 1986, of several paediatric units from our hospital to another hospital, outside the city centre. The high frequency of "C upsaliensis" may be explained by the large number of immigrants, mostly from Morocco and Turkey in our study population. During the summer many may return to their countries to visit family. The accompanying children are suddenly exposed to a new microbiological environment, usually with poor sanitary and over-crowded conditions. A late summer peak of C jejuni infections has been discussed,15 which might partly explain the high frequency of "C upsaliensis" from July to October. However, we are not able to explain the high frequency from November to January. In any case, this would suggest that "C upsaliensis" may be added to the list of enteric organisms responsible for traveller’s diarrhoea. Several groups have considered "C upsaliensis" as a cause of diarrhoea .4-5,7,16 There are several reasons why we believe that "C upsaliensis" can cause diarrhoea in man: (1) they were the only oganisms detected in 83 patients; (2) their presence in large numbers (greater than 105 colony forming units per gram faeces); (3) the presence of diarrhoea in 71 out of 77 patients where "C upsaliensis" was the only organism isolated; and (4) the eradication of the organism with disappearance of diarrhoeal symptoms after antibiotic therapy in all 13 patients treated. The onset of diarrhoeal disease was sudden and the disease was usually mild and lasted for less than a week.
C jejuni subsp doylei has been isolated from the gastric antral epithelia of adults17 and from the faeces of children with diarrhoea.18 The clinical significance of this new subspecies has not yet been established. We isolated Cjejuni subsp doylei as the single organism in 4 children, all with diarrhoea. This suggests that this organism might be pathogenic in man. We have no strong arguments to suggest that C hyointestinalis causes gastroenteritis, since in our first case this organism was isolated in a child with typhoid fever, and, in our second case, it was isolated in an adult with duodenal ulcer. We recommend that routine microbiology laboratories use a selective medium in combination with the filter method. This would significantly expand the genus Campylobacter. Continuing efforts should be made to develop new media for isolating "unusual" campylobacter and to defme additional phenotypic characteristics that may be exploited for identification and classification in the clinical laboratory.
REFERENCES 1. Sandstedt K, Ursing J, Walder M. Thermotolerant Campylobacter with no or weak catalase activity isolated from dogs. Curr Microbiol 1983; 8: 209-13. 2. Sandstedt K, Ursing J. Campylobacter upsaliensis, a new species, formerly the CNW group. XIV int congr Microbiology, Manchester, UK, Sept 7-13, 1986: 37. 3. Goossens H, De Boeck M, Coignau H, Vlaes L, Van den Borre C, Butzler JP. Modified selective medium for the isolation of Campylobacter spp from feces: comparison with Preston medium, a blood-free medium and a filtration system. J Clin Microbiol 1986; 24: 840-43. 4. Mégraud F, Bonnet F. Unusual Campylobacter in human feces. J Infect
1986; 12: 275-76. 5. Patton CM, Shaffer N, Edmonds
P, et al. Human disease associated with
"Campylobacter upsaliensis" (catalase-negative or weakly positive Campylobacter species) in the United States. J Clin Microbiol 1989; 27: 66-73. 6.
7.
Walmsley SL, Karmali MA. Direct isolation of atypical thermophilic Campylobacter species from human feces on selective agar medium. J Clin Microbiol 1989; 27: 688-70. Lastovica AJ, Le Roux E, Penner JL. "Campylobacter upsaliensis" isolated from blood cultures of pediatric patients. J Clin Microbiol 1989;
27: 657-9. 8. Goossens H, De Boeck
M, Butzler JP. A new selective medium for the isolation of Campylobacter jejuni from human feces. Eur J Clin Microbiol 1985; 2: 389-93. 9. Bolton FJ, Hutchinson DM, Coates D. Blood free selective medium for isolation of C jejuni from feces. J Clin Microbiol 1984; 19: 169-71. 10. Goossens H, Vlaes L, Galand I, Van den Borre C, Butzler JP. Semisolid blood free selective motility medium for the isolation of Campylobacter from stool specimens. J Clin Microbiol 1989; 27: 1077-80. 11. Steele TW, McDermott SN. The use of membrane filters applied directly to the surface of agar plates for the isolation of Campylobacter jejuni from feces. Pathology 1984; 16: 263-65. 12. Lior H. New extended biotyping scheme for Campylobacter jejuni, Campylobacter coli and "Campylobacter laridis". J Clin Microbiol 1984; 20: 636-40. 13. Goossens H, Pot B, Vlaes L, et al. Characterisation and description of "Campylobacter upsaliensis" isolated from human feces. J Clin Microbiol (in press). 14. Goossens H, Butzler JP. Isolation of Campylobacter upsaliensis from stool specimens. J Clin Microbiol 1989; 27: 2143-44. 15. Brasseur D, Casimir G, Goyens P. Campylobacter jejuni and infantile traveller’s diarrhoea. Eur J Pediatr 1986; 144: 517-18. 16. Taylor DE, Hiratsuka K, Mueller L. Isolation and characterization of catalase-negative and catalase weak strains of Campylobacter species, including "Campylobacter upsaliensis" from humans with gastroenteritis. J Clin Microbiol 1989; 27: 2042-45. 17. Kasper G, Dickgiesser N. Isolation from gastric epithelium of Campylobacter-like bacteria that are distinct from "Campylobacter pyloridis". Lancet 1985; i: 111-12. 18. Steele TW, Sangster N, Lanser JA. DNA relatedness and biochemical features of Campylobacter spp isolated in Central and South Australia. J Clin Microbiol 1985; 22: 71-74.
