USMLE Forums - View Single Post - Salmonellosis prolonged symptoms with the use of antibiotics?
View Single Post
Old 09-20-2010
YoramFishke's Avatar
YoramFishke YoramFishke is offline
USMLE Forums Veteran
Steps History: 1+CK+CS
Posts: 248
Threads: 11
Thanked 334 Times in 132 Posts
Reputation: 364

Nontyphoid Salmonella gastroenteritis is generally self-limited. In a Cochrane Database of Systematic Reviews article, 12 trials showed no significant change in the overall length of the illness or the related symptoms in otherwise healthy children and adults treated with a course of antibiotics for nontyphoid Salmonella disease. Antibiotics tend to increase adverse effects and prolong Salmonella detection in stools.23

However, antibiotic treatment should be considered on a case-by-case basis to include patients with severe symptoms.24 Antibiotics are currently indicated for infants up to 2 months of age, elderly, immunocompromised, those with a history of sickle cell disease or prosthetic grafts, or patients who have extraintestinal findings. Treatment of those at-risk patients should last 2-5 days or until the patient is afebrile.3

Salmonella infections are commonly treated with fluoroquinolones or third-generation cephalosporins, such as ciprofloxacin and ceftriaxone. In 2004, the prevalence of resistance among nontyphoid Salmonella isolates was 2.6% for quinolones and 3.4% for third-generation cephalosporins.25

Enteric or typhoid fever is best treated with antibiotics for 5-7 days for uncomplicated cases and up to 10-14 days for a severe infection.3 Bacteremia and focal infections may require antibiotics for up to 4-6 weeks depending on the site of infection and serotype of Salmonella. Specific surgical intervention is often necessary in conjunction with antibiotic management. Chronic Salmonella carriers require 1-3 months of oral antibiotics depending on the serotype, susceptibility, and antibiotic used.

Some evidence suggests that fluoroquinolones may be used in children with infections that are difficult to treat. When treating children and pregnant women, note that treatment with fluoroquinolones should be carefully weighed against the possibility of damaging developing cartilage.26

Salmonella antibiotic resistance is a global concern that includes multi-drug resistant strains.15 Traditional first-line antibiotic medications include ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole. Resistance to these first-line antibiotics defines multi-drug resistance in S enterica.27 Despite the increase in ciprofloxacin resistance in typhoid and paratyphoid, it is still considered the drug of choice by many physicians. However, in the case of treatment failures, a third-generation cephalosporin and macrolide are good alternatives.28

Outbreaks show that a connection may exist between antimicrobial drug treatment and the risk of disease from Salmonella.29 A mouse model has shown enhanced ability of Salmonella to translocate the intestinal tract more easily in the presence of antibiotics.8

Subsequently, stool and blood cultures and sensitivities are important, as susceptibilities not only vary depending on region of the world but also locally.

Fluoroquinolone resistance is an important factor in Salmonella typhi and was reported by the CDC to be 41.8% in 2004. Trimethoprim-sulfamethoxazole and chloramphenicol have a 13.2% prevalence of resistance in Salmonella typhi, while ampicillin, streptomycin, and sulfisoxazole are 11.8%.25

In a Cochrane Database of Systematic Reviews article, 38 trials showed a reduced clinical relapse rate using fluoroquinolones versus chloramphenicol. However, this same review was not statistically significant for clinical failure or microbiological failure and was limited for other comparisons including children.30 Additionally, because nalidixic acid resistance is no longer a reliable method for detecting decreased ciprofloxacin susceptibility, international in vitro studies suggest that gatifloxacin may be more active than ciprofloxacin in these isolates.31
Reply With Quote
The above post was thanked by:
LionofJudo (09-20-2010), rigbbm (03-08-2020)