Enteric fever is a systemic infection caused by Salmonella enterica,
including S. enterica serotype Typhi (S. typhi) and
serotype Paratyphi (S. paratyphi). Gold standard for
diagnosing typhoid is bacterial isolation of the organism in blood
cultures [1]. We present antibiotic sensitivity/resistance pattern of
salmonella isolates over a 30-month period.
Blood was drawn from 315 children (age 1-15 years)
suspected to be having typhoid fever. It was inoculated immediately in
PF bottles which showed positivity between 5-9 hours [2]. This blood was
further streaked upon enriched media (XLDAgar) and (DCAgar). As the
colonies appeared, species identification and Antibiogram was done by
Vitek 2 systems [3].
TABLE I Sensitivity Pattern of S. typhi and S. paratyphi B
|
S. typhi |
S. para |
|
|
(N=220) |
typhi B (N=5) |
|
Ampicillin |
131(59.5) |
3
(60) |
|
Amoxy-Clavulonic acid |
123(55.9) |
2
(40) |
|
Piperacillin-Tazobactum |
220(100.0) |
5
(100) |
|
Cefuroxime |
135(61.4) |
4
(80) |
|
Cefotaxime |
64(29.1) |
0
(0) |
|
Cefixime |
102(46.4) |
2
(40) |
|
Ceftriaxone |
164(74.5) |
3
(60) |
|
Cefoperazone-Sulbactum |
220(100.0) |
5
(100) |
|
Ceftazidime |
205(93.2) |
4
(80) |
|
Cefepime-Tazobactum |
130(59.1) |
3
(60) |
|
Ofloxacin |
133(60.5) |
4
(80) |
|
Ciprofloxacin |
129(58.6) |
4
(80) |
|
Levofloxacin |
184(83.6) |
4
(80) |
|
Moxifloxacin |
144(65.5) |
2
(40) |
|
Gentamicin |
116(52.7) |
2
(40) |
|
Tobramycin |
198(90.0) |
5
(100) |
|
Amikacin |
164(74.5) |
5
(100) |
|
Nitrofurantoin |
137(62.3) |
5
(100) |
|
Cotrimoxazole |
148(67.3) |
4
(80) |
|
Meropenem |
204(92.7) |
5
(100) |
|
Azithromycin |
120(54.5) |
3
(60) |
|
Chloramphenicol |
205(93.2) |
3
(60) |
|
Values in No.(%) of
strains sensitive. |
Out of 315 children with suspected typhoid fever who
underwent blood culture and sensitivity, 225 tested positive for
Salmonella. Table I present the distribution and
antibiotic sensitivity pattern of Salmonella isolates. As 129 isolates
of S. typhi revealed sensitivity towards Ciprofloxacin, we
retested these isolates with Nalidixic acid and found that 17 strains
were resistant to it. The only isolate of Salmonella paratyphoid A
was resistant to Ampicillin, quinolones, cefotaxime and gentamicin, and
one out of five Salmonella paratyphoid B strain was
extended-spectrum beta-lactamase producer, exhibiting multidrug
resistance.
Widespread use of fluoroquinolones has resulted in
emergence of S. typhi strains with reduced susceptibility and
nalidixic acid-resistance. High frequency of nalidixic acid resistance,
and multidrug resistance has also been documented earlier [4].
Prescribing antibiotics based on culture and sensitivity of the organism
may restrain the further spread of drug resistance in pediatric
population [4].
Contributors: Both authors participated in data
collection, manuscript writing, and its final approval.
Funding: None; Competing interests: None
stated.
References
1. Nagshetty K, Channapa ST, Gaddad SM. Antimicrobial
susceptibility of Samonella typhi in India. J Infect Dev Ctries.
2010;4:70-3.
2. REF 259794 BacT/ALERT PF-bioMerieux. Available
from:http://microsite.biomerieux-usa.com/bact/resources/package-inserts/PF.pdf.
Accessed September 12, 2014.
3. Funke G, Monnet D, deBernardis C, Graevenitz AV,
Freney J. Evalution of the VITEK 2 system for rapid identification of
medically relevant gram-negative rods. J Clin Microbiol. 1998;36:7.
4. Madhulika U, Harish BN, Parija SC. Current pattern
in antimicrobial susceptibility of Salmonella typhi isolates in
Pondicherry. Indian J Med Res. 2004;120:111-4.
