Ciprofloxacin therapy for typhoid fever needs reconsideration

Area of Science:

• Microbiology
• Infectious Diseases
• Pharmacology

Background:

• Multidrug-resistant Salmonella enterica serotype Typhi outbreaks in the late 1980s led to ciprofloxacin becoming a first-line treatment for enteric fever.
• Since 1994, reduced susceptibility to ciprofloxacin has been widely reported, posing therapeutic challenges.

Purpose of the Study:

• To review the drug resistance patterns of Salmonella Typhi in central India between 1988 and 2005.
• To evaluate the efficacy of ciprofloxacin and assess the potential for reintroducing older antibiotics.

Main Methods:

• A minimum inhibitory concentration (MIC) study using the agar dilution method was performed on 314 Salmonella Typhi stock cultures.
• Isolates with high-level ciprofloxacin resistance (MIC > 1 mg/l) were further tested using the Epsilometer test (E-test).

Main Results:

• Ciprofloxacin resistance significantly increased from 1989-1994 (< or = 0.125 mg/l) to 2004-2005 (88.2% of isolates had MIC > 0.125 mg/l, with 15% showing high-level resistance).
• Multiple drug resistance to chloramphenicol, cotrimoxazole, and ampicillin declined from over 90% in 1990-1991 to 5.6% in 2004-2005.

Conclusions:

• Ciprofloxacin should be withdrawn as a therapeutic agent for enteric fever due to widespread resistance.
• Declining multidrug resistance suggests that older drugs like chloramphenicol, cotrimoxazole, and ampicillin could be reconsidered for treating enteric fever.