Campylobacter enteritis: clinical and epidemiologic features

Adhesive Escherichia coli in inflammatory bowel disease and infective diarrhoea

The clinical features of ulcerative colitis and Crohn's disease are similar to those of infections of the bowel, although their cause is uncertain. Many bacteria that cause intestinal diseases adhere to the gut mucosa, and adhesion of pathogenic Escherichia coli is resistant to D-mannose. The adhesive properties of isolates of E coli were assessed by assay of adhesion to buccal epithelial cells with mannose added. The isolates were obtained from patients with inflammatory bowel diseases (50 with a relapse of ulcerative colitis, nine with ulcerative colitis in remission, 13 with Crohn's disease, and 11 with infectious diarrhoea not due to E coli) and 22 controls. The median index of adhesion to buccal epithelial cells (the proportion of cells with more than 50 adherent bacteria) for E coli from patients with ulcerative colitis in relapse was significantly higher (43%) than that for controls (5%) and patients with infectious diarrhoea (14%). The index was not significantly different among isolates from patients with ulcerative colitis in relapse, Crohn's disease (53%), and ulcerative colitis in remission (30%). If an index of adhesion of greater than 25% is taken as indicating an adhesive strain 86% of isolates of E coli from patients with inflammatory bowel disease were adhesive compared with 27% from patients with infective diarrhoea and none from controls. The adhesive properties of the isolates from patients with inflammatory bowel disease were similar to those of pathogenic intestinal E coli, raising the possibility that they may have a role in the pathogenesis of the condition; the smaller proportion of adhesive isolates in patients with infective diarrhoea due to other bacteria suggests that the organism may be of primary importance rather than arising secondarily.

Influence of strain characteristics and immunity on the epidemiology of Campylobacter infections in Thailand

To determine how strain differences and immunity affect the clinical expression of Campylobacter infections, we conducted a study of acute diarrheal disease in Thailand in which specimens from children with Campylobacter infections were cultured weekly for up to 12 weeks to determine the serotype-specific length of time of convalescent-phase excretion and rate of reinfection. Levels of immunoglobulin G to cell-surface antigens of C. jejuni were determined in another population of healthy children who were closely related by age and location to the children in the diarrheal disease study. Campylobacter species were initially isolated from 18% of 586 children under 5 years old with diarrhea; most isolates in Thailand belonged to serotypes commonly found in developed countries. C. coli was significantly less often associated with symptomatic infections and with bloody diarrhea than C. jejuni (P less than 0.001 and P = 0.045, respectively). The peak age of isolation and the peak level of immunoglobulin G to Campylobacter species occurred before 2 years of age. The mean duration of convalescent-phase excretion was 14 +/- 2 (standard error of the mean) days for children less than 1 year old and 8 +/- 2 days for children 1 to 5 years old (P = 0.02, t test). Infection with another Campylobacter serotype was found in 34% of 105 children during the 12-week follow-up period. The rate of reinfection in these children was 15% (range, 8 to 22%) each week. Hyperendemic exposure to Campylobacter species in Thailand confers immunity to infection that is associated with an early peak in specific serum antibodies and an age-related decrease in the case-to-infection ratio and duration of convalescent-phase excretion but does not prevent asymptomatic infections.

The genus Campylobacter: a decade of progress

In 1977, microbiologists and clinicians were awakened to the importance of the genus Campylobacter when it was learned that one species, Campylobacter jejuni, was a major cause of human enteritis. In the following decade substantial advances were made in diagnosis, isolation technology, identification, classification, serotyping, and epidemiology. The genus has undergone rapid expansion as advantage was taken of the deoxyribonucleic acid-deoxyribonucleic acid hybridization technique in defining new species. The 14 species now included in the genus, however, constitute a widely diverse group, and one species, C. pylori, which is associated with human gastroduodenitis, is under consideration for reassignment to another genus. The nomenclature of the subspecies of C. fetus has been resolved and the role of C. fetus subsp. fetus as an agent of human infections has been more clearly defined. The thermophilic campylobacteria that are etiological agents of human enteritis now include three species, C. jejuni, C. coli, and C. laridis. Recently defined species that have also been implicated as enteritis-causing agents include C. hyointestinalis, "C. upsaliensis," "C. cinaedi," and "C. fennelliae." The aerotolerant campylobacteria are now included in the species C. cryaerophila, and the campylobacteria isolated from salt marshes are included in C. nitrofigilis. The taxonomy and nomenclature of C. sputorum have been revised. C. sputorum now consists of three biovars (biotypes). Two of these, biovar sputorum and biovar bubulus, were previously considered to be separate subspecies and the third, biovar fecalis, was previously regarded as a separate species and known as "C. fecalis." The former subspecies C. sputorum subsp. mucosalis has been elevated to the rank of species. C. mucosalis is metabolically closely related to C. consisus. Human pathogens have not been identified among C. sputorum, C. mucosalis, or C. concisus. The goal of this article is to review developments during the last 10 years with emphasis on changes in taxonomy that are important from the perspective of the clinical microbiologist.

Prevalence of enteric pathogens in homosexual men with and without acquired immunodeficiency syndrome

We studied 388 homosexual or bisexual men from the Baltimore-Washington area to define the spectrum of enteric pathogen carriage in a population at high risk for "gay bowel syndrome" in association with human immunodeficiency virus infection. Seventy-seven patients with acquired immunodeficiency syndrome, 68 gay men with symptoms of acute diarrhea or proctitis, and 243 gay men without gastrointestinal symptoms and participating in a natural history study of human immunodeficiency virus infection were selected for study. Approximately 12% of the asymptomatic men harbored at least one enteric pathogen; the most frequently recovered were Chlamydia trachomatis, herpes simplex virus, and Giardia lamblia. Men carrying a pathogen were more likely to be human immunodeficiency virus seropositive (48%) than men without a pathogen (25%) (p = 0.018), more likely to have fewer T helper cells (p = 0.015), and more likely to have a mucopurulent exudate (p = 0.014). We recovered an agent of enteric disease from 68% of gay men presenting with diarrhea or proctitis. Campylobacter species, herpes simplex virus, Neisseria gonorrhoeae, C. trachomatis, G. lamblia, and Shigella species were identified most frequently. The most common pathogen associated with diarrhea in acquired immunodeficiency syndrome was Cryptosporidium (16% of 49 cases). Other agents identified were Clostridium difficile, Vibrio parahemolyticus, Campylobacter species, G. lamblia, Isospora, and cytomegalovirus. Approximately half of the identifiable etiologic agents of diarrhea in acquired immunodeficiency syndrome patients were treatable with antibiotics, but these agents required special culture procedures for detection.

Characterization of freshly isolated Campylobacter coli strains and suitability of selective media for their growth

Typical and atypical Campylobacter strains were isolated from the colons of cattle and swine by techniques that enabled the selective pressures of antibiotics to be avoided. Some cephalothin-susceptible strains and a strain with an indeterminate hippurate reaction were classified as Campylobacter coli by DNA homology testing. Tetracycline-resistant isolates were obtained from animals with no recorded exposure to antibiotics. A selection of 12 C. coli and 6 C. jejuni strains was used to determine the ability of fresh isolates to grow on a range of selective media. C. coli isolates were inhibited more than C. jejuni on selective media containing antibiotics. The least inhibitory media were Skirrow medium (M. B. Skirrow, Br. Med. J. 2:9-11, 1977) and the charcoal-based media developed by Hutchinson and Bolton (D. N. Hutchinson and F. J. Bolton, J. Clin. Pathol. 37:956-957, 1984) and Karmali et al. (M. A. Karmali, A. E. Simon, M. Roscoe, P. C. Fleming, S. S. Smith, and J. Lane, J. Clin. Microbiol. 23:456-459, 1986). The plasmid contents of the isolates did not appear to be related to their sensitivity to growth on selective (antibiotic-containing) media. The study indicates that selective media used to detect Campylobacter spp. could select against the isolation of C. coli.

Response of Campylobacter jejuni to combinations of ferrous sulphate and cadmium chloride

On Mueller Hinton (MH) agar, Campylobacter jejuni showed 20.0 and 30.9 mm zones of inhibition surrounding discs impregnated with 2.5 and 20 micrograms CdCl2 respectively. The minimal inhibitory concentration (MIC) ranged from 0.64 to 3.2 micrograms CdCl2/ml of MH agar for four C. jejuni strains. In the presence of 23 micrograms FeSO4/ml of MH the MIC increased to a range of 1.5-5.4 micrograms CdCl2/ml of MH. Moreover, the numbers of colonies present on MH supplemented with FeSO4 were greater than on MH without iron. The growth response of C. jejuni in the presence of 0.025% (w/v) FeSO4 in MH broth was increased about 10,000 fold in three of four strains when compared with the growth in unsupplemented MH broth. Zones of inhibition surrounding 20 micrograms discs of CdCl, were 50.6 and 24.4 mm on MH and Campy-BAP media respectively, with cells grown on MH. These results suggest that the blood-containing medium 'neutralized' the biocidal influence of the CdCl2. In comparison, C. jejuni inoculum from fluid thioglycollate (FT) medium showed smaller zones of inhibition. These decreased from 34.9 mm on MH agar to 19.6 mm on Campy-BAP agar, suggesting that components in the FT growth medium ameliorated the toxic influence of CdCl2. Atomic absorption spectroscopy analysis indicated mean values (mg/100 g dry weight) of selected metals bound by C. jejuni as: Cu, 10.4; Mg, 146; Na, 2385; Fe, 45.1; Zn, 13.0; and K, 172.

Evaluation of the campyslide agglutination test for confirmatory identification of selected Campylobacter species

The utility of a rapid latex slide agglutination test (Campyslide; BBL Microbiology Systems, Cockeysville, Md.) in detecting selected Campylobacter spp. was evaluated and compared with that of conventional identification methods. Isolated colonies suggestive of Campylobacter spp. were tested directly from primary selective media after incubation at 42 degrees C under microaerophilic conditions. Stock cultures of Campylobacter jejuni (n = 27) and C. coli (n = 3) were correctly confirmed to the genus level by latex agglutination when tested in pure cultures or isolated from seeded human feces. A total of 50 fresh clinical isolates of Campylobacter spp. (45 C. jejuni and 5 C. coli) were examined, with complete agreement observed between the latex test and conventional methods. Of 173 non-Campylobacter isolates tested from primary plates, only 1 rough strain of Pseudomonas aeruginosa produced a false-positive result. Although the manufacturer recommends a 30-min antigen extraction, 1 or 5 min was found to be sufficient. Also, confirmation could be achieved within 24 h of inoculation of clinical specimens, 2 days earlier than with conventional methods.

Escherichia coli associated with childhood diarrheas

We studied 2,246 episodes of childhood diarrhea over a 2-year period in a general hospital serving a population of about one million on the island of Hong Kong. Rotavirus (24%) and nontyphoid salmonellas (23%) were the most common causal agents, followed by Campylobacter sp. (9%). Rotavirus occurred largely during winter, whereas salmonellas and Campylobacter sp. occurred more commonly during summer and autumn, respectively. Enterotoxigenic Escherichia coli was rarely isolated (1%), and the isolates were clonally diverse. A small percentage (2.8%) of E. coli had serological specificities commonly associated with enteropathogenic E. coli, but only two of the isolates were also positive for HEp-2 adhesive factor. Pure or heavy and predominant growth of E. coli was obtained in repeated stool cultures of 432 (19%) of these episodes, which did not yield any of the above-mentioned pathogens. Although associated with diarrhea, these E. coli isolates possess neither the pathogenic attributes of enterotoxigenic E. coli nor the properties commonly associated with enteropathogenic E. coli. Enteroinvasive E. coli and enterohemorrhagic E. coli were considered unlikely causes on clinical grounds.

Production of a unique cytotoxin by Campylobacter jejuni

Campylobacter jejuni is an important diarrheal pathogen worldwide; the mechanisms by which it causes disease remain unclear. Because of its association with inflammatory diarrhea, we postulated that C. jejuni might produce a cytotoxin similar to that produced by Shigella sp., enterohemorrhagic Escherichia coli O157, or Clostridium difficile. Filtrates of 12 polymyxin-treated isolates of C. jejuni were placed on HeLa cells (sensitive to Shiga toxin cytotoxicity) and Chinese hamster ovary (CHO) cells. Of 12 isolates of C. jejuni tested, 5 killed 50% of the cells at greater than or equal to 1:4 dilutions of filtered suspensions of 10(9) bacteria per ml; killing was similar in HeLa and CHO cells (the CHO cells being insensitive to Shiga cytotoxin). One isolate produced a titer of 1:32 to 1:128. The relative potency in HeLa cells was comparable to that of E. coli strains that produce intermediate amounts of Shiga-like toxin. The other seven strains showed no cytotoxic effect, nor did the control diluents, polymyxin B, or supernatants of C. jejuni not treated with polymyxin B. Sonication also released active cytotoxin, but slightly less well than did polymyxin. The cytotoxic effect was dose dependent. Concentration of the C. jejuni in suspension by 10-fold before treatment with polymyxin B resulted in a 10-fold increase in the 50% cytotoxic dose. The cytotoxin effect was not neutralized by Shiga toxin immune serum against either Shiga-like toxin I or II or by anti-Clostridium difficile antiserum. The C jejuni cytotoxin was partially labile to trypsin (0.25%) and to heating to greater than or equal to 60 degrees C. Cytotoxicity was retained in Scientific Products dialysis tubing D1615-1 (Mr cutoff, 12,000 to 14,000). Some isolates of C. jejuni release a substance lethal to HeLa or CHO cells in vitro that is distinct from Shiga-like or Clostridium difficile toxin. This cytotoxin may contribute to the colonic mucosal invasive process that characterizes C. jejuni enteritis.

Campylobacter etiology in human gastroenteritis demonstrated by antibodies to acid extract antigen

Campylobacter antibodies of the immunoglobulin G (IgG), IgM, and IgA classes were determined by enzyme immunoassay with acid glycine extract antigen in patients and controls involved in two Campylobacter outbreaks and in 266 unselected patients with acute enteritis. The assay showed a specificity of 99% for each immunoglobulin class in sera from 200 healthy blood donors. Elevated Campylobacter antibody titers were shown in 97% of stool culture-positive patients involved in the outbreaks. Rapid changes of IgA and IgM Campylobacter antibodies were typical of the early phase of serologic response in the outbreaks and thus offered the best diagnostic value in the serologic diagnosis of acute campylobacteriosis. In unselected patients with acute enteritis, the assay revealed elevated Campylobacter antibody titers in 37 patients, of whom only 12 had had positive Campylobacter stool cultures. In the sera of patients with other bacterial findings in addition to high titers of Campylobacter antibodies, no cross-reacting antibodies were found, but there was evidence of several mixed infections.

Comparison of different procedures, transport media, and enrichment media for isolation of Campylobacter species from healthy laying hens and humans with diarrhea

A comparison was made with some of the available transport and enrichment media for the isolation of Campylobacter species. The merits of duplicate versus single sampling were also investigated. Fecal samples from 721 healthy laying hens and 328 patients with diarrhea were included in the study. The media compared were modified Stuart medium, Campythio-glycolate medium, semisolid motility test medium, and Campylobacter enrichment broth. The isolation rate of Campylobacter species was significantly increased by taking duplicate instead of single samples. The highest outcome was found when one of the two samples was an enrichment medium, such as semisolid motility test medium.

Campylobacter diarrhea in an adult mouse model

An adult mouse (18-20 g) model was developed for studying the pathogenesis of Campylobacter isolates. Iron-loaded BALB/c mice given 10(8)-10(9) Campylobacter colony forming units by intraperitoneal injection developed a severe mucoid diarrhea within 4 h. Severe diarrhea, consisting of unformed stools containing blood, mucus, and fecal leukocytes, persisted for 24 h. Diarrheal symptoms in surviving mice resolved gradually; no diarrhea was observed 5 days after inoculation. Mice not pretreated with iron developed no diarrheal symptoms, and no severe diarrhea was produced in mice inoculated orally. A transient (less than 24 h) bacteremia occurred in mice inoculated either orally or intraperitoneally. Liver, spleen, and kidney were positive for Campylobacter for 48 h; intestinal contents were positive for 5-7 days. Mice given greater than or equal to 10(10) colony forming units showed symptoms of endotoxemia (ruffled fur, inactivity, shaking, tearing, and hypothermia) and died without diarrheal symptoms. Mice given nonpathogenic Escherichia coli strain HB101, heat-killed C. jejuni cells (greater than 10(10)), C. jejuni lipopolysaccharide extract, or purified lipopolysaccharide from either Vibrio cholerae 569B or Salmonella typhimurium showed no diarrheal symptoms.

Two-year survey of etiologic agents of diarrheal disease at San Lazaro Hospital, Manila, Republic of the Philippines

The prevalence of bacterial pathogens and rotavirus in 2,908 patients with diarrhea who were admitted to San Lazaro Hospital in Manila in 1983 and 1984 was determined. One or more enteric pathogens were isolated or detected in samples from 1,698 (58.4%) patients. Isolation rates for the various enteropathogens were as follows: rotavirus, 30.6%; Shigella spp., 11.6%; Salmonella spp., 9.2%; enterotoxigenic Escherichia coli (1983 only), 7.8%; Vibrio cholerae biotype eltor, 3.8%; non-O1 V. cholerae, 2.8%; Vibrio parahaemolyticus, 1.7%; other Vibrio spp., 1.1%; Campylobacter jejuni, 3.0%; Aeromonas hydrophila, 1.3%; and Plesiomonas shigelloides 1.1%. Giardia lamblia and Entamoeba histolytica were detected in 0.6 and 0.1%, respectively, of stool samples examined. Determination of the etiologic role of isolates was complicated by one or more of the following factors: isolation of multiple enteric pathogens (302 cases); isolation of Salmonella spp., enterotoxigenic E. coli, and C. jejuni from a similar proportion of asymptomatic control patients and patients with diarrhea; and isolation of a high proportion of certain pathogens (especially Salmonella spp.) only from enrichment broth, suggesting infection with a small number of organisms. Isolation of V. cholerae eltor was seasonal, with the majority of cases occurring in the rainy months. In addition, the number of patients with diarrhea increased with the onset of the monsoon rains and peaked during the months of maximum rainfall. Rotavirus infection occurred in both children and adults throughout the year and was the most frequently identified cause of diarrhea in children under 5 years of age. Shigella spp. were the most common agents of diarrhea in adults.

Isolation of Campylobacter spp. from pigeon feces by a combined enrichment-filtration technique

A technique combining enrichment in Preston enrichment broth and direct filtration onto chocolate agar was used to isolate Campylobacter species from pigeon feces. Campylobacter jejuni was isolated from 106 of 200 samples tested; 105 strains were isolated by enrichment-filtration, and 84 strains were isolated by direct plating. Most of the strains grew after 48 h at 37 degrees C.

Factors affecting production of coccoid forms by Campylobacter jejuni on solid media during incubation

Conditions influencing the conversion of oxygen into toxic derivatives in media were investigated for their effects on production of coccoid forms in cultures of the enteric pathogen Campylobacter jejuni. Compared with stored media, production of coccoid forms was less on freshly prepared media. Whether freshly prepared or stored before use, brucella agar media produced the fewest coccoid forms under the test conditions. Addition of supplements used as detoxifying agents minimized production of these forms on media but antibiotic formulations used in selective media did not influence production of coccoid forms. Furthermore, the type of incubation atmosphere and the strain of C. jejuni influenced the proportions of coccoid forms in cultures. It was deduced from electron microscopy observations during prolonged incubation of cultures that the process of conversion to coccoid forms involves a loss of spiral morphology, a shortening of the cell and retraction of the cytoplasm towards a cell terminal region. Coccoid forms and some intermediate forms in thin sections were found to lack cell integrity. It is concluded that coccoid form production in cultures is a degenerate response to toxic oxygen derivatives in cultures.

Prospective study of enteric Campylobacter infections in children from birth to 6 months in the Central African Republic

A survey of enteric Campylobacter infections was performed in Bangui, Central African Republic, with a cohort of 127 children from birth to 6 months of age by biweekly culture of stools; 82 infections were observed, and 41.7% of the children presented at least 1 infection before 6 months of age. Only 15.9% of the infected children had a diarrheic syndrome; moreover, 61.5% of these diarrheic children had another enteropathogen associated with Campylobacter species. In about half the cases, Campylobacter spp. were excreted for more than 4 days. More than half of the children had at least one diarrheic episode, for which an enteropathogen was identified in one third of the cases, before 6 months of age.

A blood-free medium for isolation of thermophilic Campylobacter species

A blood-free medium for the recovery of thermophilic Campylobacter was compared with Butzler Medium Virion during a one-year study using 2,893 human feces samples. Ninety Campylobacter strains (3.1%) were isolated after incubation for 48 h at 42 degrees C in a candle jar atmosphere. Three strains of Campylobacter jejuni were isolated on the blood-free medium only and one on Butzler Medium Virion only. Fecal flora was equally well inhibited on both media except for gram-positive organisms, which were completely inhibited only on the blood-free medium.

Infectious diarrhoea in tropical and subtropical regions

Diarrhoeal diseases are among the most important health problems in the world today. While they are generally mild, nuisance illnesses in the developed world, where clean water and sanitation are adequate, these diseases are the most common cause of death in young children in the developing world, where clean water is not available and sanitation is inadequate. In these areas, up to 25% of children may never reach their fifth birthday. In addition, although the impact on growth and nutritional status is difficult to quantify, the cumulative toll on overall child health is enormous. A wide variety of infectious agents are implicated in the aetiology of acute diarrhoeal illness, many of which were unknown 20 years ago. The epidemiology, pathogenic mechanisms and clinical presentation of the common bacterial and viral pathogens, as they are currently understood, will be discussed in this chapter.

Seasonal occurrence of Campylobacter spp. in surface waters and their correlation with standard indicator bacteria

Campylobacter jejuni, Campylobacter coli, and a Campylobacter-like organism were isolated from a number of natural water sources in central Washington, including ponds, lakes, and small mountain streams at elevations ranging from 1,460 to 5,400 feet (ca. 445 to 1,646 m) above sea level. At the two sites where extensive sampling was done, the bacteria were recovered throughout the year. Generally, the recovery rates were highest in the fall and winter months and lowest during the spring and summer months. Campylobacter density did not show significant correlation with microbiological (plate counts of fecal and total coliforms, fecal streptococci, and heterotrophic bacteria) or physical (water temperature, pH, and conductivity) parameters.

Erythromycin-resistant Campylobacter infections in Thailand

Erythromycin therapy was compared with no treatment in a prospective trial of acute diarrheal disease among 100 infants in an orphanage in Bangkok. Within 24 h of the onset of diarrhea, 50 children received erythromycin ethylsuccinate (40 mg/kg per day) in four divided doses for 5 days. Campylobacter jejuni isolated from 31, Campylobacter coli isolated from 21, and Shigella spp. isolated from 21 of 100 children were the most commonly recognized pathogens; use of a sensitive, nonselective method substantially increased Campylobacter isolation. Treatment with erythromycin had no effect on the duration of diarrhea caused by Campylobacter spp., Shigella spp., or other agents; 37% of the treatment group and 35% of the control group had diarrhea for 1 week. Of 23 Campylobacter strains isolated from the treatment group before treatment, 15 (65%) were resistant (MIC, greater than or equal to 8 micrograms/ml) to erythromycin. Among orphanage-acquired strains, 53% of 43 C. jejuni strains and 91% of 23 C. coli strains were resistant to erythromycin compared with 11% of 114 C. jejuni strains and 46% of 35 C. coli strains that were community acquired. Erythromycin resistance is common among Campylobacter strains in Bangkok, especially in an institutional setting, which may account for the lack of efficacy of erythromycin for treatment of acute diarrheal illnesses.

Efficacy of some methods and media for detecting and enumerating Campylobacter jejuni in frozen chicken meat

Four of five strains of Campylobacter jejuni survived in chicken meat stored at -18 degrees C for 12 months. Direct plating of samples was superior to the most probable number technique for enumerating C. jejuni. Enrichment culture using the Doyle & Roman enrichment method resulted in the highest rates of detection. Packaging under an atmosphere of CO2 did not substantially influence survival.

Decontamination of Campylobacter jejuni on chicken drumsticks using chemicals and radiation

A trial was conducted to compare the efficacy of four disinfectants and radiation to reduce the level of C. jejuni contamination on poultry meat. Two levels of each treatment were applied to chicken drumsticks inoculated with a known concentration of a strain of Campylobacter jejuni, biotype 1, isolated from a human patient with diarrhea. Radiation using a cobalt-60 source at a level of 0.5 KGy effected a 99% surface reduction in C. jejuni. With a mean initial surface contamination level of 1.1 X 10(3) Colony Forming Units/cm2, 1 KGy completely eliminated C. jejuni. Glutaraldehyde at 0.5% concentration for 30 minutes had an efficacy similar to the lower dose of radiation. Chlorine showed a negligible effect on C. jejuni. Succinic acid and Poly (hexamethylenebiguanide hydrochloride) were statistically similar in their effectiveness, ranking between glutaraldehyde and chlorine. These results strongly indicate that, of the alternatives tested, low-dose radiation is the method of choice for reducing Campylobacter contamination of poultry products.

Gastrointestinal zoonoses

Infectious gastrointestinal diseases affect man and animals throughout the world. Certain etiologic agents (for example, Salmonella spp., Campylobacter jejuni, Yersinia enterocolitica, Cryptosporidia, Strongyloides stercoralis, Echinococcus granulosa) seem to have the potential to be transmitted from pets to people, causing severe disease in the latter. Other agents seem unlikely to be transmitted but may have the potential to be zoonoses. This article discusses proved, suspected, and possible zoonotic agents that may originate from the gastrointestinal tract of dogs and cats.

Clinical and laboratory approaches to evaluate diarrheal disorders

Diarrheal disorders are the result of excessive fluid and electrolyte loss through the gastrointestinal tract. Many different underlying mechanisms are known to cause diarrhea. Fordtran suggested that in secretory diarrhea the osmolality of stool water should be accounted for by its electrolyte contents. Therefore, the osmotic gap between the measured osmolality and that estimated from electrolyte contents should be small. In osmotic diarrhea, due to the presence of the osmotic agent, there should be a greater gap between the measured and the estimated osmolalities. Osmotic gaps varying from 100 to 40 mOsm have been used arbitrarily in literatures to define the underlying pathogenesis. Because of the uncertainty, the usefulness of these measurements remains in question. In this article, methods used to measure stool osmolality and electrolyte contents are reviewed. Limitations of these measurements are discussed. Measurements derived from various diarrheal disorders revealed that the basic concepts put forward by Fordtran are corrected. However, we found that the osmotic gaps (measured osmolality - 2 [Na + K] in secretory diarrheal disorders are frequently negative numbers. In osmotic diarrhea, the osmotic gap (greater than 160 mOsm) is substantially greater than the figures used in the literature. In many diarrheal disorders the osmotic gap falls between the two extremes and the pathogenesis is multifactorial in origin. Under these circumstances, stool osmolality and electrolyte measurements provide little insight into the underlying mechanism causing the diarrhea. Furthermore, stool contains many biologically active organisms which can alter the stool osmolality. Unless these effects are appreciated, an inaccurate interpretation of these measurements may result.

Evaluation of four enrichment media for isolation of Campylobacter jejuni

Diarrheal stool specimens were inoculated into the following media: alkaline peptone water (APW), Bruce-Zochowsky medium (BZ), Campylobacter enrichment broth (CEB), Campy-thio broth (CT), and Skirrow blood-agar (SK) plate. All media were incubated at 42 degrees C in microaerophilic conditions for 24 h. Afterwards, a new SK plate was inoculated from every liquid medium. Campylobacter jejuni was isolated from 43 of the 259 specimens when CT was used, from 45 when APW was used, from 46 when BZ was used, and from 46 when CEB was used; these totals include specimens that grew after enrichment only, on SK plates only, and both after enrichment and on SK plates. No significant differences were found between the isolates obtained with and without enrichment procedures.

Methods for detecting and enumerating Campylobacter jejuni and Campylobacter coli in poultry

Methods, media, and biochemical tests for detecting, enumerating, isolating, and identifying Campylobacter jejuni and C. coli in foods are summarized with special consideration of poultry and poultry products. Information is drawn largely from the American Public Health Association Compendium of Methods for the Microbiological Examination of Foods and the US Food and Drug Administration Bacteriological Analytical Manual for Foods. Reference is also made to recently advanced techniques and procedures.

Modified selective medium for isolation of Campylobacter spp. from feces: comparison with Preston medium, a blood-free medium, and a filtration system

Our previously described (H. Goossens, M. De Boeck, and J. P. Butzler, Eur. J. Clin. Microbiol. 2:389-393, 1983) selective medium, consisting of cefoperazone (15 mg/liter), rifampin (10 mg/liter), colistin (10,000 IU/liter), and amphotericin B (2 mg/liter) (medium M1), for the isolation of Campylobacter jejuni and Campylobacter coli from stool specimens was modified as follows: cefoperazone (30 mg/liter), rifampin (10 mg/liter), and amphotericin B (2 mg/liter) (medium M2). A comparative study of the isolation of Campylobacter spp. from stool specimens was carried out with medium M1; medium M2; a selective blood-free medium consisting (per liter) of charcoal (4 g), ferrous sulfate (0.25 g), sodium pyruvate (0.25 g), casein hydrolysate (3 g), sodium deoxycholate (1 g), nutrient broth no. 2 (25 g), agar (12 g), and cefoperazone (32 mg) (medium M3); and Preston medium containing (per liter) trimethoprim (10 mg), rifampin (10 mg), polymyxin B (5,000 IU), and cycloheximide (100 mg) (medium M4). We also included a filtration system in which membrane filters were applied directly to the surface of the nonselective blood-free medium distributed in small petri dishes. A total of 5,276 stool specimens were tested: 2,788 stool specimens were tested on M1 and M3 in study 1; 2,488 stool specimens were inoculated on the four selective media in study 2, and the last 986 specimens of the 2,488 were tested in parallel with the filtration system. In study 2, 128 Campylobacter strains were isolated from 126 different patients; 85.0, 88.3, 82.5, and 66.6% of these strains were isolated on M1, M2, M3, and M4, respectively. No contaminating fecal flora was found on 65.4, 70.7, 62.4, and 40.3% of the M1, M2, M3, and M4 plates, respectively. Furthermore, C. coli was found to be more susceptible to antibiotics present in the selective media, particularly colistin and polymyxin B, than was C. jejuni. We therefore recommend M2 for the isolation of Campylobacter spp. Finally, the filtration method was found to be easy and cheap; although the sensitivity was low, this method allowed the isolation of new Campylobacter spp. which seem to be associated with diarrhea.

Immune response of athymic and euthymic germfree mice to Campylobacter spp

Pure cultures of several Campylobacter spp. induced a specific humoral immune response after they colonized and infected gnotobiotic mice; however, Campylobacter-immune mouse serum was not bactericidal (in vitro), manifested a weak agglutination reaction (in vitro), and showed specificity (strain 45100-immune mouse sera) for the homologous (infecting) Campylobacter strain, but was not able to passively protect germfree athymic (nu/nu) BALB/c mice against Campylobacter infection and diarrhea. Active immunization of germfree nu/nu mice with Formalin-killed C. jejuni also did not protect the gnotobiotic mice from Campylobacter infection and diarrhea. It appears from the results of our initial gnotobiotic studies that antibodies in serum against the infecting strain of C. jejuni may not play an essential role in resistance to Campylobacter disease in mice.

Isolation and characterization of cephalothin-susceptible Campylobacter coli from slaughter cattle

In a recent meat survey, 10 of 13 (77%) Campylobacter coli isolates were susceptible to cephalothin. These organisms were isolated from nine slaughter cattle from eight meat packing establishments. All 10 isolates grew at 43 degrees C but not at 25 degrees C, were catalase and oxidase positive, and were susceptible to nalidixic acid (30 micrograms) and cephalothin (30 micrograms). The cultures were subsequently identified as C. coli serogroup 20, biotype I (Lior scheme). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that protein and lipopolysaccharide profiles of whole cell preparations of the 10 cephalothin-susceptible strains and the reference strain for C. coli serogroup 20 were very similar. The plasmid profiles of these 11 strains were identical.

Comparative efficacy of seven selective media for isolating Campylobacter jejuni

Diarrheal stools from 263 patients were inoculated on seven selective media: Butzler selective medium, Blaser medium, Skirrow blood agar, Preston campylobacter selective medium, Preston campylobacter blood-free medium, Butzler Virion medium, and modified Preston medium (with amphotericin B [2 mg/liter]). A similar number of Campylobacter jejuni strains were isolated from all the media studied; nevertheless, the presence of competing fecal flora (FF) made the detection of suspect colonies difficult. Preston campylobacter blood-free medium with cefoperazone yielded the greatest number of C. jejuni isolations, and contaminating FF grew in only 9% of the plates showing C. jejuni growth; all the other media allowed the abundant growth of other FF, regardless of whether C. jejuni was isolated from them or not.

Early treatment with erythromycin of Campylobacter jejuni-associated dysentery in children

To evaluate the efficacy of early treatment with erythromycin on the duration of fecal excretion and of diarrhea associated with Campylobacter jejuni, 170 patients, age 3 to 60 months, were randomly assigned in a double-blind fashion to receive either erythromycin ethyl succinate or placebo immediately after being seen at Cayetano Heredia Hospital because of acute dysentery. The groups' pretreatment characteristics were comparable. Of the 30 patients with stools positive for C. jejuni, 12 were in the placebo group and 16 in the treatment group. After 2 days of treatment, none of the patients in the placebo group and 36% of those in the erythromycin group had normal stools (P less than 0.05). After 5 days of treatment, 50% of the patients in the placebo group and 93% of those in the erythromycin group had normal stools (P less than 0.02). Fecal excretion of the organism continued significantly longer in the placebo group (P less than 0.01). There were no treatment failures in the treatment group compared with five (42%) in the placebo group (P less than 0.01). Thus, early administration of erythromycin significantly reduced the duration of both diarrhea and fecal excretion of the organism in infants and children with acute dysentery associated with C. jejuni.

Isolation of Campylobacter jejuni in Hunan, the People's Republic of China: epidemiology and comparison of Chinese and American methodology

The incidence of infection with Campylobacter jejuni was determined in individuals with and without diarrheal disease seen at a hospital in Changsha, China. Stool specimens were cultured by two methods: one developed by the Chinese and a second control method used commonly in the United States. Among people with diarrhea, 18.7% of the 48 children and 8.7% of 104 adults were infected with Campylobacter jejuni. In the group without diarrhea, 8.6% of 105 children but none of 76 adults tested had the organism in their stool. Of the 27 total positive cultures, the Chinese method was positive in 26, compared with 21 for the control method. The Chinese culture method was at least as sensitive and specific as the American method. The biochemical characteristics and antibiotic sensitivities of Chinese isolates were similar to organisms isolated in other parts of the world. This study shows that Campylobacter jejuni is a common enteric pathogen in China and that the asymptomatic carrier state of this organism is significant in children.

Western blot analysis of intestinal secretory immunoglobulin A response to Campylobacter jejuni antigens in patients with naturally acquired Campylobacter enteritis

Secretory immunoglobulin A (sIgA) response at the intestinal mucosa is a primary defense against enteric infections. We sought to determine which antigens of Campylobacter jejuni outer membranes elicited sIgA responses in 8 patients with naturally acquired Campylobacter enteritis using Western blot analysis of fecal extracts. Naturally acquired Campylobacter infection elicited an sIgA response in 7 of 8 patients. Of these 7 patients, 5 had Campylobacter-specific sIgA titers of 1:16 and two had titers of 1:64. The C. jejuni antigens eliciting sIgA production varied, but 5 of 8 patients exhibited reactions to a 63-kilodalton flagellar antigen, and 7 of 8 patients had a reaction with a 58- and a 44-kilodalton antigen of C. jejuni and Campylobacter coli. Reaction with a 14.5- and a 97-kilodalton antigen was observed with the only stool that contained gross blood and mucus. Reactions with Campylobacter antigens were not detected in the fecal extracts of 5 healthy individuals. Identification of the antigens of C. jejuni that elicit an sIgA response may help us to better understand the immunology of Campylobacter enteritis and to identify antigens that are important in vaccine development.

Persistence of multiply antibiotic-resistant Campylobacter jejuni in a patient with the acquired immune deficiency syndrome

Chronic diarrhea due to Campylobacter jejuni has been described in patients with hypogammaglobulinemia. A patient with the acquired immune deficiency syndrome (AIDS) and normal total serum immunoglobulins had persistent diarrhea and C. jejuni on stool culture for seven and a half months despite repeated antibiotic therapy. Antibiotic sensitivity studies revealed the C. jejuni to be multiply antibiotic-resistant. Evaluation of the mechanism of resistance showed the organism harbored a conjugative plasmid capable of transferring resistance to tetracycline, but not to other antibiotics. It is concluded that C. jejuni infection may rarely result in chronic diarrhea in patients with AIDS. The combination of an immune deficiency state including abnormal B cell function previously described in AIDS and multiple antibiotic resistance may have contributed to the persistence of the organism in this case.

Clinical approach to intestinal infections in homosexual men

The list of infectious agents that cause intestinal disorders in homosexual men is polymicrobial. Classic enteric pathogens, anorectal venereal pathogens, and more recently, opportunistic pathogens have been reported to occur in high prevalences in both symptomatic and asymptomatic homosexual men. This article reviews the epidemiology, clinical presentation, diagnosis, and treatment of these infections.

Enrichment for detection of Campylobacter jejuni

Gifu anaerobe-modified semisolid medium supplemented with vancomycin, polymyxin B, trimethoprim, and amphotericin B can serve as an efficient enrichment for the recovery of Campylobacter jejuni under aerobic conditions. It is superior to the direct plating method in its recovery of very small numbers of C. jejuni. Blood supplementation, agitation, and elevated temperatures are not required for this improved recovery.

Epidemic campylobacteriosis associated with a community water supply

In May 1983, an estimated 865 cases of epidemic gastrointestinal disease occurred in Greenville, Florida. Surveillance of pharmacy sales of antidiarrheal medicines suggested that the outbreak was confined to Greenville and its immediate vicinity. Surveys demonstrated that the gastrointestinal illness attack rates inside and outside the city limits were 56 per cent (72/128) and 9 per cent (7/77), respectively (relative risk (RR) = 6.2); consumption of city water was associated with illness (RR = 12); and as water consumption increased, the attack rate also increased (p less than 0.001). Four adults were hospitalized and one outbreak-related case of Guillain-Barre' syndrome was identified. Campylobacter jejuni was isolated from specimens from 11 ill persons; serologic studies showed the development of Campylobacter-specific antibodies. Fecal coliforms were found in water samples, but Campylobacter was not recovered from water. The city water plant, a deep well system, had numerous deficiencies including an unlicensed operator, a failure of chlorination, and open-top treatment towers. Birds were observed perching on the open-top treatment tower. Of 38 birds trapped seven weeks later, 37 per cent harbored C. jejuni; however, plasmid and serotyping studies showed that strains were not the same as the common strain from ill persons. This outbreak suggests that water systems that are unprotected from contact with birds may become contaminated and a source of outbreaks of human campylobacteriosis.

The role of poultry and meats in the etiology of Campylobacter jejuni/coli enteritis

To determine the role of meats as possible sources of infection leading to Campylobacter jejuni/coli (CJC) enteritis, 218 cases and 526 controls were selected from the King County Group Health Cooperative (GHC) population from April 1982 through September 1983. All subjects were interviewed regarding food consumption one week prior to case onset. Consumption of chicken and cornish game hen were both associated with more than a doubling of the risk of CJC enteritis: for chicken (relative risk = 2.4, 95% CI = 1.6-3.6), and for game hen, (RR = 3.3, 95% CI = 1.1-9.8). The consumption of raw or rare chicken was even more strongly associated (RR = 7.6, 95% CI = 2.1-27.6). Strains of CJC bearing R factors for tetracycline were equally as likely as tetracycline-susceptible strains to have been acquired from chicken and game hens. Processed turkey sandwich meats (RR = 1.7, 95% CI = 1.0-2.9) raw or rare fish (RR = 4.0, 95% CI = 1.1-14.5) and shellfish (RR = 1.5, 95% CI = 1.1-2.1) were the only other meats reported to have been eaten significantly (p less than .05) more often by cases than by controls. These data along with the results of bacteriologic sampling of meats from King County retail food markets during the same period suggest that ingestion of contaminated chicken is a primary source of CJC enteritis, contributing to approximately half of the cases.