African Journal of Biotechnology Vol. 10(9), pp. 1700-1704, 28 February, 2011
Available online at http://www.academicjournals.org/AJB
ISSN 1684–5315 2011 Academic Journals
Incidence and susceptibility pattern of clinical isolates from pus producing infection to antibiotics and Carica papaya seed extract A. O. Idowu*, B. B. Oluremi and N. I. Seidu
Department of Pharmaceutical Microbiology, Faculty of Pharmacy, Olabisi Onabanjo University, Ago-Iwoye, Ogun State,
The prevalence of bacterial pathogens isolated from pus producing infections (wound, eye and ear) randomly collected from the Medical Microbiology Laboratory of University College Hospital (UCH),Ibadan, Nigeria was determined. Their susceptibility to selected antibiotics and Carica papaya seed extracts was investigated. Bacterial pathogen identity was confirmed based on standard methods which included, Gram stain reaction, colonial morphology on media, lactose fermentation, catalase,oxidase,coagulase and indole tests. The antibiogram was carried out using standard disc agar diffusion method employing commercially prepared antibiotic disc (Abtek Limited) of amoxycillin (25mcg), co-trimoxazole (25 mcg), nitrofurantoin (300 mcg), gentamicin (10 mcg), nalidixic acid (30 mcg),ofloxacin (30 mcg), augmentin (30 mcg) and tetracycline (10 mcg). A total of 58 isolates were obtained out of which 31 were from wound, 12 from ear and 15 from eye. 41 of the isolates were recovered from adults, while 17 were from children. Staphylococcus aureus was found to be the most common organism recovered (51.7%), followed by Klebsiella spp. (11%), Pseudomonas aeruginosa (11%),Proteus spp. (6.9%) and Escherichia coli (3.4%). From wound swabs, S. aureus isolates was the highest (51.6%) followed by Klebsiella spp. (22.6%), Pseudomonas aeruginosa and Proteus spp. (9.7% each) and E. coli (6.45%). In ear infection, P. aeruginosa accounted for 58.3%, S. aureus 25%, while Klebsiella spp. and Proteus spp. accounted for 16.6% each. In eye infection, S. aureus and Klebsiella spp. were more frequently isolated with 73.3 and 20%, respectively. The antibiogram studies showed that all the organisms were highly sensitive to ofloxacin as follows: S. aureus (80%), Klebsiella spp. (100%), P.aeruginosa (100%), Proteus spp. (100%) and E. coli (100%) while P. aeruginosa (63.6%), S. aureus (76.6%) and E. coli (100%) were sensitive to gentamicin and Klebsiella spp. (18.2%) and Proteus spp. (25%) were resistant. The organisms were resistant to all the other antibiotics tested namely: amoxycillin, co-trimoxazole, nitrofurantoin, nalidixic, augmentin and tetracycline. C. papaya extract showed antimicrobial activity which compared favourably with the commercial antibiotic discs against the Gram positive and negative bacteria tested, except Klebsiella spp. The highest activity was demonstrated against P. aeruginosa. Key word: Susceptibility, bacterial pathogens, pus, infection, antibiotics, Caricapapaya extract.
INTRODUCTION
Infectious diseases are the world’s major threat to human
the use of antimicrobial agents is to cure or prevent
health and account for almost 50,000 deaths everyday
infectious diseases by using the best available agent.
(Ahmad and Beg, 2001). The most important reason for
The benefits to the individual who deserves treatment
must be weighed against the risk of the emergence of
resistant microorganisms to the public (Kunin, 1988).
Rapid development of multidrug resistance by micro-
*Corresponding author. E-mail: Solaid2002@yahoo.com. Tel:
organisms to available antimicrobial agents has further
complicated the threat of infectious diseases to human
Table 1. Source and number of isolates used. Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa
ATCC 27853and Esherichia coli ATCC 25922were used as control
Children
strains. Diameters of growth inhibition zones were recorded to the
nearest mm for an average of 2 readings in each case.
Processing of plant materials C.papaya fruits col ected from Sagamu in Ogun state were
authenticated at the Forestry Research Institute of Nigeria (FRIN),
Ibadan, Nigeria. The unripe pawpaw fruits were cut open and the
health. The choice of antimicrobial chemotherapy is ini-
seeds removed and put in clean polythene nylon. The seeds were
air dried for two weeks to prevent loss of active compounds. They
tial y dependent on clinical diagnosis. However, for many
were grounded into powder with electric blender. 500 g of the
infections, establishing a clinical diagnosis implies deter-
powder was soaked in methanol (96%) for one week and then
mining possible microbiological causes which requires
filtered. The filtrate was dried to yield a semisolid mass referred to
laboratory information from samples col ected, preferably
as extract. The crude extract was reconstituted using 50% dime-
before antibiotic therapy is begun. Laboratory isolation
thylsuphoxide (DMSO) to obtain concentrations of 250, 200, 150,
and susceptibility testing of organisms make diagnosis to
be established and also make drug selection more
Determination of the activity of C.papaya seed extract on the
The local use of natural plants as primary health reme-
bacterial pathogens
dies due to their pharmacological properties is quite
common in Asia, Latin America and Africa (Bibitha et al.,
Antimicrobial assay
2002). Plants have the major advantage of stil being the
most effective and cheaper alternative sources of drugs
Antimicrobial activity of seed extract of the plant sample was
(Pretorian and Watt, 2001). Caricapapaya (family
evaluated by the cup plate agar diffusion method (Doughari et al.,
2007) on Muel er Hinton agar. Aliquots of extract reconstituted in
Caricacea) is a monosexual plant of Central American
50% dimethylsulphoxide (DMSO) and diluted to obtain concen-
origin. The latex from the leaves has been used as anti-
trations of 250, 200, 150, 100 and 50 mg/ml were applied in each
helmintics for the treatment of infection of bacterial origin
wel in the culture plates previously seeded with the test organisms.
A pre-diffusion time of 30 min was al owed at room temperature and
This research was undertaken to determine the pre-
the plates were incubated at 37°C for 24 h. S. aureus ATCC 25923,
valence of bacterial pathogens that are commonly
P. aeruginosa ATCC 27853and E. coli ATCC 25922were used as
control strains. Diameters of growth inhibition zones were recorded
responsible for pus producing infections of wound, eye
to the nearest mm for an average of 2 readings in each case.
and ear and to investigate the susceptibility of the
organisms to selected antibiotics as wel as seed extracts
Out of the 58 clinical bacterial isolates used in this study,
MATERIALS AND METHODS
31 (53.4%) were obtained from wound samples, 12
(20.6%) from ear samples and 15 (25.8%) from eye
Collection and preparation of test clinical isolates
samples. 41 (70.6%) of al the isolates were recovered
Fifty eight (58) bacterial isolates from wound, eye and ear clinical
from adults, while 17 (29.3%) were from children (Table
samples were randomly col ected from the Microbiology Laboratory
1). The distribution of the different pathogens showed
of University Col ege Hospital (UCH), Ibadan, Nigeria. The isolates
that S. aureus was the most prevalent (51.7%), fol owed
were obtained on nutrient agar slants and incubated at 37°C for 24
by Klebsiel a spp.(11%), Pseudomonas (11%), Proteus
spp. (6.8%)and E. coli (3.4%) (Table 2). From the wound
The isolates were re-identified and confirmed using standard
microbiological method which included, gram staining, colonial mor-
samples, the distribution of the isolates recovered was as
phology on media, lactose fermentation, catalase, oxidase, coagu-
fol ows: S. aureus (51.6%), Klebsiel a spp.and Proteus
spp.(22.6%)each, P. aeruginosa (9.7%), Proteus spp.
(9.7%)and E. coli (6.45%). P.aeruginosa was the most
common organism isolated from ear specimen (58.3%)
Antibiotic sensitivity testing
fol owed by S. aureus (25%), Klebsiel a spp.(8.3%) and
Antibiotic susceptibility testing was performed by the disc diffusion
Proteus spp. (8.3%). S. aureus isolates was predominant
assay on Mul er Hinton Agar as described by Bauer et al. (1966)
in the eye samples (51.7%), fol owed by Klebsiel a spp.
using the fol owing antibiotics disc: amoxycil in (25 mcg), co-
trimoxazole (25 mcg), nitrofurantoin (300 mcg), gentamicin (10
The result of the antibiogram of the pathogenic isolates
mcg), nalidixic acid (30 mcg), ofloxacin (30 mcg), augmentin (30
showed that al the organisms were highly susceptible to
mcg) and tetracycline (10 mcg). Interpretation of diameter of growth
inhibition zone was done by using the manufacturer’s manual.
ofloxacin. The proportion of the isolates that were sus-
Organisms were scored as either sensitive or resistant.
ceptible to ofloxacin were as fol ows: S. aureus (80%),
Table 2. Distribution of different pathogens. Organism Wound swab (%) Ear swab (%) Eye swab (%)
Table 3. Antibiogram profile of bacterial isolates from pus producing infections. Organism
AMX, Amoxicil in; COT, co-trimoxazole; NIT, nitrofurantoin; GEN, gentamicin; NAL, nalidixic acid; OFL, ofloxacin; AUG, augmentin; TET, tetracycline;
Klebsiel a spp. (100%), P. aeruginosa (100%), Proteus
et al. (2003) and Bisi et al. (2005) that S. aureus is the
spp. (100%) and E. coli (100%) (Table 3).Only three of
leading etiological agent in wound infections. However, P.
the organisms: S. aureus (76.6%), P.aeruginosa (63.6%)
aeruginosa which accounted for only 11% of the total
and E. coli (100%) were sensitive togentamicin, while
isolates from the three sites was the predominant
Klebsiel a spp. (18.2%) and Proteus spp. (25%) were
organism of al the isolates obtained from ear specimen
resistant to it. The pathogens were resistant to al the
(58.3%). This is in agreement with earlier studies
other six antibiotics tested. Thisshowed that these
(Adedeji et al., 2007; Ogisi and Osamar, 1982; Selina,
categories of the isolates were multiresistantstrains
2002) that rated P. aeruginosa as the most common
(defined as resistance to at least threeclasses of
bacteria isolated from mild to severe form of external
antibiotics). The comparative antibiotics susceptibilityof
otitis and chronic suppurative otitis media. Pus production
bacterial isolates from the different sites ofinfection is
is a common manifestation of infections due to S. aureus
shown in Table 4. C. papaya showed antibacterialactivity
in tissues and sites with lowered host resistance such as
against P. aeruginosa, while no activitywas recorded
damaged skin and mucous membrane,where it may
against any of the Klebsiel a spp. Isolates (Table 5).
produce skin lesion such as boil or surgical site
infections. This possibly explain the high incidence of the
organism from bacterial isolates obtained from this pus
DISCUSSION
producing infection of eye, ear and wound in this and
The knowledge of the bacteriology of an infection and the
laboratory susceptibility testing of micro-organism
The susceptibility studies showed that the bacterial
implicated could make drug selection in antimicrobial
pathogen was only highly susceptible to ofloxacin with
chemotherapy more rational. Suppurative infection of the
varying degree of susceptibility to gentamicin. Resistance
skin, ear and eye are common occurrences in
to commonly used antibiotics such as amoxycil in,
hospitalized and out patients. Wound infection is
cotrimoxazole, nitrofurantoin, nalidixic acid and
regarded as the most common nosocomial infection in
tetracycline was predominant in the organisms.Al the
surgical patients (Dionigi et al., 2001). It has been
strains of the isolates used were resistant to the
associated with increased trauma care, prolonged
potentiated B-lactam antibiotic, augmentin. The
hospitals stay and treatment. (Bowler et al 2001).
phenomenon of multidrug resistance (defined as
The result of this study showed that S. aureus which
resistance to more than 3 classes of antibiotics) was
accounted for 51.7% prevalence is the leading etiological
noticed among the isolates in this study.
agent of pus producing infections of the eye, ear and
There was no defined pattern or difference in terms of
wound. S. aureus was the predominant isolates from
sensitivity to antibiotic from the isolates obtained from
wound (51.6%) and eye (51.7%) specimens. This is in
different sites of infection of the eye, ear and wound. The
agreement with the reports of Akonai et al. (1991), Shittu
emergence of resistance to antimicrobial agents is a
Table 4. Comparative analysis of susceptibility pattern of bacterial isolates from pus producing infection in relation to sample Organism 30 S. aureus(30) wound 11 Klebsiella spp. wound 11 P. aeruginosa wound 4 Proteus spp. wound 2 E. coli wound
AMX, Amoxicil in; COT, co-trimoxazole; NIT, nitrofurantoin; GEN, gentamicin; NAL, nalidixic acid; OFL, ofloxacin; AUG, augmentin; TET,
global public health problem, especial y among pathogens
causing nosocomial infection. (CDC, 1999). This is
The demonstration of activity by the extract against the
essential y due to improper use of antibiotics by health
tested bacterial isolates provide the scientific basis for the
professionals, unskil ed practitioners and laypersons,
local usage of the plant in the treatment of various pus
poor drug quality and inadequate surveil ance programme
producing infection such as wound infection and otitis
media. It is also an indication that the plant is a potential
Adequate epidemiological data on characterization and
source for the production of novel drugs for the treatment
antibiotic susceptibility of bacterial pathogen is an
essential ingredient to guide empiric antibiotic therapy in
This study showed that S. aureus is the leading
the ambulatory setting. This would reduce or eliminate
aetiologic agent in pus producing infections and that
errors in empirical selection of either ineffective or
ofloxacinand gentamicin may be used in the treatment of
expensive drugs, prolonged hospitalization and higher
such infections before microbial and sensitivity test are
There is need for the evaluation of plants for
High level resistance to common antibiotics
antibacterial activity because of the twin effect of high
encountered in most of the isolates of bacterial
cost and the development of resistance to synthetic/
pathogens is an indication that control measures have to
conventional drugs used in orthodox practice.In this
be put in place, particularly in the administration of
study, the seed extracts of C. papaya showed good
antibiotics in the hospitals. Patients should be educated
antibacterial activity against the Gram negative than the
on the consequences of indiscriminate use of antibiotics
Gram positive organisms tested. This result is at disparity
and there should also be an antibiotic resistance
with an earlier study that indicated that plant extracts are
more active against Gram positive than Gram negative
The high sensitivity of the tested organism to ofloxacin
bacteria (Jigna et al., 2006). It however agreed with the
may not serve any useful purpose in children where its
findings of Doughari et al. (2007), where it was
use is contra-indicated. It should also be used with
demonstrated that C. papaya extract showed a higher
caution in adults because the emerging low level of
activity against Gram negative bacteria than Gram
resistance may become high in future due to selective
Table 5. Comparative antimicrobial activities of C. papaya seed extract with commercial antibiotics Inhibition zone (mm) Strain of organism C. papaya seed extract (mg/ml) GEN (mcg) OFL(mcg)
GEN = Gentamicin; OFL = Ofloxacin; S = Staphylococcusaureus; PS = Pseudomonasaeruginosa; P =
Proteus spp; E = Escherichiacoli.
pressure of exposure as a result of constant use because
associated approaches to wound management. Clin. Microbiol.
of arbitrary prescription of the antibiotic.
Dionigi R, Rovera F, Dionigi G, Imperatori A, Ferrari A, Dionigi P,
Dominioni I (2001). Risk factor in surgery. J. Chemother., 13:6-11.
Doughari JH, Elmahmood AM, Mansara S (2007).Studies on the
REFERENCES
antibacterial activity of root extracts of Carica papaya L . Afr. J.
Adedeji GB, Fagade OE, Oyelade AA (2007). Prevalence of
Fajinmi AK, Taiwo AA (2005). Herbal remedies in animal parasitic
Pseudomonas aeruginosa in clinical samples and its sensitivity to
diseases in Nigeria. A review. Afr. J. Biotechnol. 4(4): 303-307.
citrus extract. Afr. J. Biomedical Res. 10: 183-187.
Jigna P, Karathia N, Chanda S (2006). Evaluation of antibacterial
Ahmad I, Beg AZ (2001). Antimicrobial and phytochemical studies on 45
activity and photochemical analysis of Bauhinia variegate. Afr. J.
Indian Medicinal plants against multidrug resistant human pathogens.
Kunin C (1988). Urinary tract infections in children due to drug resistant
Akonai AK, Lamikanra AB, Onipede AO (1995). Incidence of pathogenic
bacteria. J. Trop. Paediatr. 47(6): 374-375.
micro organisms in clinical specimens from hospitals in South
Ogisi FO, Osama YY (1982). Bacteriology of chronic otitis media in
Western Nigeria. East Afr. Med. J. 72: 436-441.
Bauer AW, Kirby WMM, Sherris JC, Turk M (1966). Antibiotic
Pretorius CJ, Watt E (2001). Purification and identification of active
susceptibility testing by standardized single disc method, Am. J. Clin.
components of carpobrotus edulis L. J. Ethnopharm. 76:87-91.
Selina C (2002). Pseudomonas infection Emeducine World Medical
Bibitha B, Jisha VK, Salitha CV, Mohan S, Valsa AK (2002).
Antibacterial activity of different plant extracts. Indian J. Microbiol. 42:
Shittu AO, Kolawole DO, Oyedepo EAR (2003). Wound infections in two
health institutions in IleIfe, Nigeria: Results of a cohort study.
Bisi-Johnson MA, Kolawole DO, Shittu AO (2005)Epidemiology analysis
of clinical isolates of Staphylococcus aureus in Ile-Ife,Nigeria.
World Health Organization (1999). The Global Threat of Antibiotic
Bowler PG, Duerden BI, Amstrong DG (2001). Wound Microbiology and
resistance. Publication of the World Health Organization. Chapter 3.
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(1) Polypharmacy has multiple definitions: the concurrent use of multiple medications, prescribing more medication than clinically indicated, a medical regimen that includes at least 1 unnecessary medication or the use of 5 or more medications.1 A 2003 survey of over 17,000 Medicare recipients >65 years old showed:2 o 46% of seniors take 5 or more medications daily o 73% of seniors with chro