Flexneri Infection Research Articles

Shigella-specific IgA in saliva of children with bacillary dysentery.

To study the secretory immune response after Shigella infection, the anti-lipopolysaccharide and anti-Shiga-toxin response in saliva, obtained from children with confirmed shigellosis and healthy children, were determined by enzyme-linked immunosorbent assay and by Western blot. Children with infection showed high titers compared to healthy controls. After Shigella dysenteriae type 1 infection a significant change in titer could be observed in a large number of cases, in contrast to Shigella flexneri infection. It appeared that, in children living in endemic areas, infection with one serotype can give a rise in antibody titer to another serotype. This could be ascribed to polyclonal B cell activation since children in endemic areas routinely show relatively high titers to Shigella antigens. We conclude that the dynamics of salivary anti-Shigella LPS and anti-Shiga-toxin in children with dysentery indicate that it can be applied to studies of immune response in shigellosis for epidemiological and vaccination purposes.

Shigella-specific IgA in saliva of children with bacillary dysentery

To study the secretory immune response after Shigella infection, the anti-lipopolysaccharide and anti-Shiga-toxin response in saliva, obtained from children with confirmed shigellosis and healthy children, were determined by enzyme-linked immunosorbent assay and by Western blot. Children with infection showed high titers compared to healthy controls. After Shigella dysenteriae type 1 infection a significant change in titer could be observed in a large number of cases, in contrast to Shigella flexneri infection. It appeared that, in children living in endemic areas, infection with one serotype can give a rise in antibody titer to another serotype. This could be ascribed to polyclonal B cell activation since children in endemic areas routinely show relatively high titers to Shigella antigens. We conclude that the dynamics of salivary anti- Shigella LPS and anti-Shiga-toxin in children with dysentery indicate that it can be applied to studies of immune response in shigelosis for epidemiological and vaccination purposes.

Epidemiologic Aspects of Shigellosis and Other Causes of Dysentery in Thailand

Nearly 20% of children seen in the outpatient department of Children's Hospital in Bangkok, Thailand, for diarrheal disease had bloody diarrhea. Shigella species and enteroinvasive Escherichia coli--isolated from 13% and 2% of children with diarrhea, respectively--were the most frequent causes of bloody diarrhea. Campylobacter species and nontyphoidal Salmonella species were also isolated frequently but were much less often associated with bloody diarrhea. Shigella species were rarely isolated from patients who did not have diarrhea, while Campylobacter and Salmonella species were isolated frequently from well children. None of the species isolated always caused bloody diarrhea. Studies on infection with Campylobacter suggest that natural immunity may prevent bloody diarrhea and in fact may eventually prevent all disease due to this organism. Studies of endemic Shigella flexneri and epidemic Shigella dysenteriae 1 in Thailand have shown that immunity may also explain an age-related decrease in rates of S. flexneri infection but not in rates of S. dysenteriae 1 isolation.

Electrolyte abnormalities associated with diarrhea in rhesus monkeys: 100 cases (1986-1987)

Summary Serum electrolyte values from 100 rhesus monkeys with diarrhea were reviewed. The most frequent finding was hyponatremia (88%), with hypochloremia next most frequently detected (80%). Metabolic acidosis was less common (59%) and usually associated with high anion gap values. Associations between electrolyte abnormalities and age, housing, or case outcome were not found. Bacteriologic culturing was performed on fecal specimens from 90 monkeys. Campylobacter coli or C jejuni alone was isolated from 42 (46.7%) specimens, C coli and Shigella flexneri were isolated from 25 (27.8%) specimens, and S flexneri alone was isolated from 6 (6.7%) specimens. A pathogen was not isolated from 17 (18.9%) specimens. Hyponatremia, hypochloremia, acidosis, and high anion gap values were most severe in monkeys infected with Campylobacter sp, either alone or with concurrent S flexneri infection. Serum sodium concentrations < 132 mEq/L and serum Cl concentrations < 93 mEq/L were consistently associated with Campylobacter sp infection.

Shigellosis in Adults

One hundred and sixteen cases of adult patients hospitalized for shigellosis have been reviewed. The most common presentation included diarrhea (most frequently watery), fever, and abdominal pain, while dysentery has been less frequent. S. flexneri infection, as compared to S. sonnei, was more common in elderly patients and in males, and was characterized by a more prolonged clinical course. Abnormalities of serum electrolytes and hepatic enzymes were the most common laboratory complications, most often seen in elderly patients. Most isolates exhibited susceptibility to the common antimicrobial agents used in shigellosis therapy.

Shigella flexneri O-antigen specific enzyme immunoassay: class-specific antibody titres against lipopolysaccharide antigen in adult Swedes with bacillary dysentery

Serum samples were collected from 14 healthy Swedes who fell ill due to bacteriologically verified bacillary dysentery caused by Shigella flexneri of various serotypes IgA, IgM and IgM serum antibody titres were estimated in enzyme immunoassays (EIA) with chemically defined S. Flexneri serotype Y lipopolysaccharide (LPS) as antigen. Serum samples collected from 35 healthy Swedes served as controls. Positive titres were defined as titres greater than the mean +2 SD in the control population. Eleven out of fourteen (79%) patients responded with positive IgA titres within the first 4 weeks after falling ill. IgM titres were positive for 4 14 (29%) in the same serum samples and IgG titres in 13 14 (93%) of the samples. All data suggest that patients showed a primary antibody response as a result of the shigella infection. One year post infection 56% showed positive IgA titres, 18% positive IgM and 82% positive IgG titres. The sensitivity of the assay was high, all patients showed one or more positive titres. In terms of specificity, the S. flexneri serotype Y LPS EIA was highly selective for IgG titres when tested on sera from 34 patients with non-flexneri shigellosis, salmonellosis, campylobacteriosis or yersiniosis diagnosed by faecal culture: 2 34 (6%) positive. IgA titres, although positive, were lower than titres seen in sera from patients with S. flexneri infection. We consider the S. flexneri serotype Y LPS EIA a useful diagnostic complement to faecal culture.

Shigellosis in the First Week of Life

The diagnosis of shigellosis is only rarely considered in the infant whose diarrhea commences during the first week of life. Haltalin1 reported six cases and reviewed seven others that had appeared in the literature up until 1967. Three other cases have been reported.2-4 We would like to describe an additional infant with onset of diarrhea due to Shigella flexneri infection on her second day of life. Case Report Patient C.E. (SLCH #72-6528) was admitted to St. Louis Children's Hospital at 36 hours of age with fever and bloody diarrhea. The mother had a third trimester urinary tract infection treated with parenteral ampicillin. No diarrhea was noted during her pregnancy.

Effect of active or passive immunization on the response of the ligated rabbit intestine to Shigella flexneri infection.

Effect of active or passive immunization on the response of the ligated rabbit intestine to Shigella flexneri infection.

TRANSFERABLE DRUG RESISTANCE AND OTHER TRANSFERABLE AGENTS IN STRAINS OF ESCHERICHIA COLI FROM TWO HUMAN POPULATIONS

232 strains of Escherichia coli isolated from patients in a mental hospital during an outbreak of Shigella flexneri infection, and 300 strains of E. coli from a more normal population, were examined for resistance to antibacterial drugs, for colicinogeny, and for the carriage of transfer factors. 78 (33.8%) of the strains from the hospital community were resistant to one or more antibacterial agents, and, of these strains, 49 could transfer their resistance to E. coli K12 or Salmonella typhimuriumin mixed culture. 72 (24%) of the 300 strains from the general population were also drug-resistant, and 31 of these carried transferable resistance. In both populations, approximately 3% of the strains carried transfer factors not associated with drug-resistance or colicinogeny.

Report on an epidemic due to Shigella dysenteriae, type 1, in the Somali interior.

Summary Shigella Group A, Type 1 (S. dysenteriae), was isolated from 18 (35%) of 51 patients with severe dysentery and was considered the etiological agent in those cases. It is thought probable that this organism was also the etiological agent in at least 27 of the 33 cases that did not yield S. dysenteriae from the single stool specimen analyzed in each case. Of the latter 33, 5 yielded S. flexneri and 1 S. boydii. A species of Salmonella was isolated from one of the cases with S. flexneri infection. S. dysenteriae was also isolated from the Uebi Scebelli River. The etiological status of S. flexneri and S. boydii in the cases in which they were found is questionable. No bacterial pathogen was found in any of the 27 cases that did not yield Shigella. Entamoeba histolytica cysts were detected in both dysenteric and control groups. No trophosoites were noted and this parasite was not considered to be an etiological agent in the present dysentery epidemic. A coprological and serological survey provided evidence of the many other microbial pathogens prevalent in this area. This epidemic of dysentery due to S. dysenteriae Type 1 is one of the very few studied in Africa.