Indian J Pediat 49 : 807,810, 1982

Antibiogram of enteropathogenic E. Coli strains ininfantile diarrhoea

S.Y. Rao, M.D., D.C.H., and P.S. Leela Naidu, M.D., D.G.a.

Antibiotic sensitivity of 65 strains of enteropathogenic E. Coli, isolatedfrom 194 cases of infantile diarrhoea was done. All the three serotypes026, 086 and 055 Were found to be sensitive to garamycin and fura­zoladine, while most of these were resistant to chloramphenicol. 026 and086 strains were resistant to neomycin also whereas it was effectiveagainst 055.

Key words : Enteropathogenic E. Coli; antibiotic sensitivity

Enteropathogenic E. Coli is oneof the common organisms responsiblefor infantile diarrhoea in childrenbelow 2 years of age. Several workersin different parts of the world carriedout in vitro antibiogram study withdifferent' antibiotics used in clinicalpractice to find out the suspectibilitypattern of prevalent strains of entero­pathogenic E. COli.1- 7

In the present study, the prevalentserotypes of enteropathogenic E.Coliwere studied. Antibiogram of thestrains isolated was carried out withcommon antibiotics administered cli­nically for the control of infantilediarrhoea.

Materials and Methods

The rectal swabs were collected frominfants and children below 2 years suffe­ring from diarrhoea, before any anti-

From Department of Microbiology,Kurnool Medical College. KurnooJ.

Reprint requests: Dr. S. Yella Rao, CivilSurgeon Bacteriologist, Regional Laboratory,Kurnool Medical College, Kurnool 518002.

biotic treatment. These children atten­ded, as out and in patients in the De­partment of Pediatrics GovernmentGeneral Hospital, Kurnoo!.

The technique adopted for isolationof enteropathogenic E. Coli from stoolsamples has been described previously.sIn vitro sensitivity pattern of isolatedenteropathogenic E.Coli strains wasstudied with nine antibiotics by agarplate diffusion method using filter paperdiscs, impregnated with the antibioticssuch as streptomycin, chloramphenicol,LedermycinR , oxytetracycline, furazoli­done (Furoxone), gentamycin, kanamy­cin, neomycin and colistin.

Disc sensitivity method was preferredfor its simplicity and rapidity though itis a qualitative method. The methodrecommended by Bailey and Scott wasfollowed for the study of antibioticsensitivity pattern.9

Results

Among 194 cases of infantile diarr­hoea, 65 cases (34%) were found to beexcreting the three serotypes of entero·

Tab

le:

Sen

siti

vity

and

Res

ista

nce

Pat

tern

of

Thr

eeS

erot

ypes

of

Ent

erop

atho

geni

cE

.Col

ito

Nin

eA

ntib

ioti

cs0

00 0

0

Dru

g02

6S

erot

ype

(n=

44

)08

6S

erot

ype

(n=

16

)05

5S

erot

ype

(n=

5)>-

i::E

:S

Per

-R

Per

-S

Per

-R

Per

-S

Per

-R

Per

-m

cent

cent

cent

cent

cent

ccnt

.... Z 0 ..... > ZS

trep

tom

ycin

1125

3375

425

1275

360

240

.... 0C

hlor

amph

enic

ol8

18.1

836

81.8

216

100

510

0c::

--

--

::l:l

ZL

eder

myc

in4

9.09

4091

.91

1610

05

100

>-

--

-t"

'

Oxy

tetr

acyc

line

4193

.19

100

03

6.81

--

1610

0-

-5

'>:l

'1:l

Neo

myc

in4

100

1610

05

100

m-

--

--

-0 ;;

Col

isti

n10

22.7

234

77.2

85

31.2

511

68.7

5-

-5

100

>-i

::l:l .....

Kan

amyc

in25

56.8

149

43.1

910

62.5

637

.55

100

-("

)-

c:n

Gen

tam

ycin

4410

0-

-16

]00

--

510

0

Fur

oxon

e44

100

--

1610

0-

-5

100

~ .j:>,.

~~ Z ? ~ -

YELLA RAO & LEELA NAIDU : ANTIBIOGRAM OF EPEe STRAINS 809

pathogenic E.Coli 026 (67.7%) 086(24.6%\ any 055 (7.7%) and theseisolated strains were tested against nineantibiotics shown in the Table.

In the present series, all the strains ofserotypes 086, 055 were resistant tochloramphenicol. All the strains ofthe three serotypes were found to besensitIve to furoxone and gentamycin.However in general a higher percentageof resistant strains were encounteredtowards tetracycline group of drugs.

Discussion

In the present study certain aspectsof the sensitivity pattern of the threeisolated serotypes are discussed.

The susceptibility pattern of the threeisolated serotypes 026, 055 and 086 inour present investigation showed highpercentage of resistance towards strep­tomycin and tetracycline group of drugs(72.3%, 95.4% and 93.8%) as both thedrugs are bacteriostatic rather thanbactericidal in the concentrationattained in the body. Theseresults in the present series coin­cide with those of Rozaneky et al3 andBhat and Myerst though the experienceof Rao and Murti4 and Chakrabarthyet al6 with these group of drugs is diffe­rent.

In our present investigation the threeisolated serotypes showed higher per­centage of resistance towards chloram­phenicol (Table). The resistance ofthese strains to chloramphenicol mighthave been due to presence of a specificresistance (R) factor. As stressed byRozansky et al this high degree of resis­tance to chloramphenicol was probably

due to wide usage of the drug both asa therapeutic and prophylactic measureagainst enteropathogenic E.Coli infec­tion.3

Neomycin had come into generaluse as an effective measure controllingenteropathogenic E.Coli serotypes andalso in preventing the susceptible con­tacts. Bhat and Myers in their compa­ra tive study of biochemical -reactionswith that of antibiotic susceptibilitypattern, described all the strains of 055serotype are to be neomycin sensitive. l

Similar sensitivity of the serotype 055(100%) was observed in the presentisolated series, whereas the other twoserotypes 026 and 086 were neomycinresistant, though neomycin is said tobe effective as described by JoanTaylor. lo Similarly neomycin resistantstrains have been isolated by Connorand Connor.7 Resistant strains ofE.Coli develop after prolonged use ofthe drug.

The present observations supportthe claim that kanamycin is a betterdrug than chloramphenicol and neomy­cin, probably due to a broad spectrumof bactericidal activity and infrequentusage of the drug in this area.

The three serotypes found in our pre­sent study are mostly resistant to colistinsulphate, as compared to the serotype0111 isolated by Kheder and Wheelerfrom infected infants.' These differences inthe sensitivity pattern of enteropathoge­nic E. Coli strains as explained byChakrabharty may depend on the originof the strain and diversity of variousserotypes.6

In the present series all the strains

InfectiousNor Amer

810 THE INDIAN JOURNAL OF PEDIATRICS

of EPEe were sensitive to the twodrugs, gentamycin and furazolidone.Rao and Murti had similar experiencewith the serotypes investigated duringtheir study towards furoxone (98.9%).4

The resistant strains of enteropa­thogenic E.Coli are being encounteredregularly with most of the commonantibiotics because of frequent usageof these drugs during repeated attacksof diarrhoea, which might have enhancedthe multiplication of the more resistantstrains of enteropathogenic E.Coli.

References

1. Bllat P, Myers R M: Laboratorystudies on enteropathogenic EscherichiaColi serotypes. Ind J Microbiol 1: 17,1961

2. Kheder J, Wheeler WE: Colistinsuppression of Escherichia Coli in stools.Am J Dis Child 108: 278, 1954

3. Rozanaky, Berant, Rosenmann. Ben-Ad,Sterk Enteroplthogenic E.Coliinfections in infants during the periodfrom 1957 to 1962. J Pediatrics 64 : 521,1964

Vol. 49, No. 401

4. Rao MK, Murti BR : A study ofthe bacterial etiology of diarrhoea anddysentery in infants and children. JAssoc Phy Ind 13 : 557,1965

5. Sengupta S R, Sharma KD: Bacte­riology of diarrhoea in infants andchildren with special reference to enter~

opathogenic E.Coli Ind J Path andBact 10 : 304, 1967

6. Chakrabarty M S, Sujata G, Dast/dar andChakrabarty AN: Sensitivity of proteusmirabilis and enteropathugenic Esch"ichiaColi strains to antibiotics. Ind J Microbiol7: 125,1967

7. Conor J 0, Connor EB:diarrhoeas. Paed Clinic14: 197,1967

8. Yella Rao S, Leela Naidu P S, SyedGhulam Afzal: Enteropathogenic E.Coliin infantile diarrhoea. Ind Paediatrics13 : 521, 1976

9. Bailey RW, Scott E G: DiagnosticMicrobiology, 4th Ed, The CV MosbyComp,my. Saint Louis 1974

10. Joan T: Enteropathogenic EscherichiaColi In Res Adv Clin Path J and A,Churchill Ltd, London Series III: 1960,p 78.