Clinical and microbiological features of Aeromonas hydrophila-associated diarrhea

Abstract

The prevalence of Aeromonas hydrophila in stool specimens from patients with diarrhea was studied during 18 months. A. hydrophila was found in 1.1% of patients with diarrhea and in none of 533 control patients (P < 0.02). Cases were detected 1.5 times more often during the summer months than the winter months, and most occurred in children less than 2 years of age. Clinical features included fever greater than 38°C (55%), abdominal cramps (35%), vomiting (25%), and duration of illness greater than 10 days (50%). Detection of A. hydrophila in stools was facilitated by the use of sheep blood agar with 15 ,ug of ampicillin per ml which was flooded with oxidase reagent after growth. A cytotoxin was produced by 62% of the isolates, and the cytotoxic strains showed positive results in a hemolysin assay and a lysine decarboxylase reaction.

A multiplex PCR for detection of enterotoxin genes in Aeromonas species isolated from foods of animal origin and human diarrhoeal samples

“…is harboured by humans in their gastrointestinal tracts both in the presence and in the absence of the disease. The rates of faecal carriage in asymptomatic persons range from 0 to 4% (Agger et al 1985;Svenungsson et al 2000), while the isolation rate from persons with diarrhoeal illness ranges from 0Á8 to 7Á4% (Agger et al 1985;Moyer 1987;Albert et al 2000).…”

Microbiological Consequences of Minimally Processed Fruits and Vegetables

“…Other emerging bacterial pathogens which could be problem in fresh fruits and vegetables are psychrotrophic pathogens, especially Listeria monocytogenes and Aeromonus hydrophila. Both of these bacteria have been isolated from fresh vegetables (Callister and Agger 1987;Ho et al 1986;Schlech et al 1983) and can cause illness (Agger et al 1985) or death (Gray and Killinger 1966;Schlech et al 1983). Moreover, growth of L. monocytogenes is enhanced by elevated carbon dioxide concentrations (Gray and Killinger 1966).…”

Mechanisms of diarrhoea

“…in Western Australia, where 11% of children with diarrhoea had enterotoxigenic Aeromonas detected in comparison with less than 1% in the control group (Burke et al, 1983). There are now many reports of patients with diarrhoea in whom Aeromonus was the only recognized pathogen and several reviews on Aeromonus-associated diarrhoea are available (Freij, 1984;Agger et al, 1985;Agger, 1986;Burke and Gracey, 1986;Sack et al, 1988;San Joaquin and Pickett, 1988). Aeromonas usually causes mild, self-limiting watery diarrhoea but can cause dysenteric symptoms (bloody diarrhoea with mucus) or persistent diarrhoea.…”