Enterotoxin produced by micrococci from cases of enteritis after antibiotic therapy

Methicillin-Resistant Staphylococcus aureus as a Probable Cause of Antibiotic-Associated Enterocolitis

Antibiotic-associated diarrhea is typically associated with Clostridium difficile. However, Staphylococcus aureus has also been described as a cause of antibiotic-associated enterocolitis and diarrhea and is likely an underrecognized etiology. We present a case of enterocolitis and urinary tract infection caused by methicillin-resistant S. aureus following antibiotic treatment.

Nosocomial antibiotic-associated diarrhea associated with enterotoxin-producing strains of methicillin-resistant Staphylococcus aureus

OBJECTIVES

The aim of this study is to present new evidence that enterotoxin-producing strains of methicillin-resistant Staphylococcus aureus may cause nosocomial antibiotic-associated diarrhea.

METHODS

We conducted a prospective study that utilized standard methods to exclude other bacterial, parasitic, and viral pathogens as causes of nosocomial diarrhea in patients with heavy growth of methicillin-resistant S. aureus in their stool. Staphylococcal enterotoxin assays were performed on S. aureus strains recovered from patients' stools and on stool specimens from affected patients. Retrospective cohort studies compared the severity of diarrhea in patients with methicillin-resistant S. aureus-associated diarrhea with that of patients whose stool did not contain the organism and with patients colonized or infected with enterotoxin-negative methicillin-resistant S. aureus strains.

RESULTS

During an 18-month period, 11 patients had nosocomial antibiotic-associated diarrhea associated with enterotoxin-producing strains of methicillin-resistant S. aureus. Other common bacterial, parasitic, and viral pathogens were excluded. S. aureus strains from the 11 patients produced staphylococcal enterotoxin A, A and B, or D. Eighty-nine percent of patients had the same enterotoxin(s) in stool specimens as produced by the strain recovered from their stool. Case patients had a greater number of days of diarrhea than patients without methicillin-resistant S. aureus in their stool (p < 0.001), or randomly selected patients colonized or infected with enterotoxin-negative methicillin-resistant S. aureus (p < 0.001).

CONCLUSIONS

Our findings provide evidence that enterotoxin-producing strains of methicillin-resistant S. aureus may cause nosocomial antibiotic-associated diarrhea. Greater recognition of this disease should result in more rapid and appropriate treatment of affected patients.

Predominant Staphylococcus aureus isolated from antibiotic-associated diarrhea is clinically relevant and produces enterotoxin A and the bicomponent toxin LukE-lukD

Staphylococcus aureus was isolated as the predominant or only isolate from cultures of stools of 60 patients over 2 years in a university hospital, leading to the collection of 114 isolates. Diarrhea was observed in 90% of the patients. Ninety-eight percent of the patients had received antibiotics in the month before the diarrhea. Ninety-two percent of the S. aureus isolates were methicillin resistant. S. aureus was encountered with antibiotic-associated diarrhea among 47 quite elderly patients affected or not affected by a gastrointestinal disease. Among the antimicrobial treatments, cessation of the previous therapy when possible or rapid application of oral vancomycin therapy was the most appropriate. Analysis of total DNA by pulsed-field gel electrophoresis revealed 27 different SmaI pulsotypes distributed in 15 clusters. The pulsotypes never differed for related isolates from a single patient, even if they originated from patients with bacteremia. S. aureus was not isolated as the predominant isolate in cultures of stools of 57 patients who received an antimicrobial treatment for more than 5 days without diarrhea. Occurence of production of both enterotoxin A and the bicomponent leucotoxin LukE-LukD by the S. aureus isolates was significantly different from that by random isolates. The results strongly suggest that when predominant in stool samples, S. aureus should be considered a possible etiologic agent for some cases of antibiotic-associated diarrhea.

Detection of antibodies to staphylococcal enterotoxins in the serum and milk of healthy goats

A study was made of the presence of antibodies (Ab) to staphylococcal enterotoxins A to E (SEA-SEE) in the serum and milk of 133 healthy goats, using a competitive ELISA method. Antibodies to some enterotoxins were detected in 83 sera (62.4%) and in 41 (30.8%) milk samples. In serum, antibodies to all SE types were detected, the most frequent being antibodies to SEA (24.8%). Milk contained antibodies to SEA, SEB and SEC, the latter being the most frequent (24.8%). A statistical study was performed to correlate the number of animals harbouring antibodies to a given enterotoxin with the presence in these animals of staphylococci producing that enterotoxin.

Antibodies to staphylococcal enterotoxins and toxic shock syndrome toxin 1 in sera of patients and healthy people in Rio de Janeiro, Brazil

Sera from 33 persons with staphylococcal infections and from 37 healthy persons were surveyed for the presence of antibody to staphylococcal enterotoxins A, B, C, D, and E and toxic shock syndrome toxin 1. Thirty-one (93.9%) of the patients and 35 (94.6%) of the control group had antibodies to one or more of the enterotoxins. The numbers of patients with antibody to the enterotoxins were as follows: A, 8; B, 9; C, 7; D, 17; E, 21; and toxic shock syndrome toxin 1, 11. The numbers of healthy individuals with antibody to the enterotoxins were as follows: A, 6; B, 12; C, 8; D, 27; E, 21; and toxic shock syndrome toxin 1, 9.

The spectrum of staphylococcal disease. From Job's boils to toxic shock

Strains of Staphylococcus aureus are known to differ in their ability to produce a number of toxins and digestive enzymes that may contribute to the organisms's virulence and invasive potential. Independent from these, however, certain strains produce a variety of specific toxins that cause specific clinical diseases, including staphylococcal food poisoning, staphylococcal enterocolitis, exfoliative skin disorders, and most recently, the toxic shock syndrome. This article reviews those diseases known to be mediated by specific staphylococcal toxins.

Antibodies to staphylococcal enterotoxin in laboratory personnel

Eighty-five percent of laboratory personnel working with staphylococcal enterotoxin had antibodies to enterotoxin in their sera, whereas only 23% of the control group had antibodies specific for enterotoxin. Two persons who carried enterotoxin B-producing staphylococci in their noses, throats, or both, had antibodies to enterotoxin B in their sera.

Permeability of the middle ear to staphylococcal pyrogenic exotoxin in otitis media

Middle ear permeability after instillation of staphylococcal pyrogenic exotoxin was studied in each of 12 cats, 6 of them with otitis media induced by obstructing their eustachian tubes. This is the first report that there is passage of toxin to the perilymph, cerebrospinal fluid and blood not only in diseased ears, but also in normal controls, 25 min and 12 h after exposure of the middle ear cavity and round window membrane to toxin. The data suggest a pathophysiological explanation for the association of otitis media and sensorineural hearing loss and/or endolymphatic hydrops; potentially both entities can be caused by exotoxins. It also documents the extraordinary capabilities of movement of staphylococcal exotoxin.