Open Access Short Research Article

Evaluation of Three Phenotypic Tests vs. Duplex (coa & mecA) PCR for Detection of Methicillin-Resistance Staphylococcus aureus (MRSA) Strains from Patients with Nosocomial Infections (NI) in a Mexican Hospital

Roberto Cabrera-Contreras, Rubén Morelos-Ramírez, Enrique Meléndez-Herrada

Microbiology Research Journal International, Page 1-7
DOI: 10.9734/BMRJ/2016/23077

Background: Staphylococcus aureus (SA) is a leading cause of hospital acquired infections worldwide. Epidemiological features have also changed in Mexican hospitals and methicillin-resistance Staphylococcus aureus (MRSA) infections appear to be an emerging phenomenon.  

Aims: The aim of the present study was to detect the amplification of both coa and mecA genes by duplex PCR in MRSA isolates from Mexican patients with NI and the comparison of these results versus three phenotypic MRSA-detection methods.

Place and Duration of Study: Department of Public Health, Faculty of Medicine, National University of Mexico (UNAM) in collaboration with a General Hospital “Gonzalo Castañeda Escobar” (HGC), Health Care & Social Services Institute for Workers (ISSSTE), between August 04-December 05.

Methodology: Among SA (n=100) strains isolated from patients with NI, 40% were MRSA. All SA strains were tested by various methods: cefoxitin (Cfx) disk-diffusion assay (DD), automated MicroScan System (MS), Oxacillin (Ox) (range 0.5 - 4.0 µg/ml) minimum inhibitory concentration (MIC), PBP2a latex agglutination test (LA) (Oxoid) and the molecular amplification by PCR of the coa and mecA genes (PCR). SA strains were previously identified by MS, and both the tube coagulase (TCT) and mannitol (MT) tests.

Results: From 100 SA strains, 35 were confirmed as MRSA isolates by detection of mecA gen by PCR in addition to only 5 strains verified phenotypically but coa gen negative. These 40 MRSA strains and 53 mecA gen negative isolates as well as 5 strains phenotypically characterized (MSSA) from NI, were assayed with all 3 laboratory tests. Only 2 clinical strains were negative to both genes: coa & mecA, but positive to all phenotypic tests. Using mecA as a gold standard (GS), category agreement for the 3 tests was: A method with higher sensitivity (SN) and specificity (SP) (SN/SP) was Cfx-DD (100/88) than other 2 methods Ox-MS (90/73) and LA (63/90). Using coa gene as a GS, category agreement for MS, and both TCT & MT were: 93/100, 95/98, and 91/98, respectively.

Conclusions: Molecular detection by PCR-duplex of coa & mecA genes, is a very useful and powerful method (93%) to precisely discriminate typical MRSA strains in the laboratory. A Cfx-DD test performed much better for detection of MRSA strains than those using OX-MS and LA. Both assays, Cfx-DD and PCR-duplex, represent a simple, rapid, reliable approaches for the detection of methicillin resistant staphylococci and could be applied to all national hospitals, to implement fast and adequate anti-MRSA therapy.

Open Access Original Research Article

Prevalence of Urinary Tract Infection among Pregnant Women Receiving Antenatal Care in Two Primary Health Care Centres in Karu Nasarawa State, Nigeria

Ajide Bukola, Adogo Lillian, Saidu Henrietta, Enna Maureen

Microbiology Research Journal International, Page 1-8
DOI: 10.9734/BMRJ/2016/23191

Aim: To determine the prevalence of urinary tract infections among pregnant women receving antenatal care in two primary health care centres in Karu Nasarawa State.

Place and Duration of Study: This study was carried out in two primary health care centres in Karu Nasarawa State between March-August, 2015.

Methodology: A total of 150 pregnant women were enrolled for this study. Mid stream urine sample was collected from each pregnant woman, analysed and cultured on cystein lactose electrolyte deficient (CLED) medium.

Results: The results revealed that the incidence of UTI in this study population was 62.67% and 94 bacterial isolates were identified based on colonial morphology, microscopic characteristics, and biochemical tests. The most predominant bacterium was Escherichia coli (22.97%). This was followed by Klebsiella spp(18.08%), Staphylococcus spp (15.95%), Proteus spp (13.82%), Staphylococcus coagulase negative (10.63%) and Enterococcus spp (8.51%). The statistical analysis carried out in this study was Chi Square (X2). X2 = 20.97, and at 0.05 degree of freedom, bacterial significance was 11.07.

Conclusion: The prevalence of urinary tract infection from this study is of significant value, therefore, screening of pregnant women for bacteriuria during antenatal visit should be a routine procedure to avoid complications in pregnancy.

Open Access Original Research Article

Antibiotics Susceptibility Profile of Extended Spectrum Beta Lactamase Producing Gram Negative Bacteria from Widal Positive Patients in Ekiti State University Teaching Hospital

J. A. Babalola, A. O. Oluyege, O. U. Lawal, O. T. Akinduro, A. O. Igbalajobi

Microbiology Research Journal International, Page 1-9
DOI: 10.9734/BMRJ/2016/22810

Aims: To investigate the age occurrence of typhoid fever, antibiotics susceptibility profile of Extended Spectrum Beta-lactamase producing gram negative bacteria recovered from the blood culture of widal positive patients attending Ekiti State University Teaching Hospital.

Place and Duration of Study: Microbiology Laboratory, Ekiti State University Teaching Hospital from August- November, 2011.

Methodology: Widal status of patients was detected using Widal Agglutination test kits. Demographic data descriptively analysed using tables and statistical software (SPSS 17 version). Isolates were identified using standard methods, subjected to antimicrobial susceptibility by disc diffusion method and extended spectrum beta-lactamase production (ESBL) detection done by Double Disc Synergy Test.

Results: A total of 99 samples were examined, 86 subjected to widal test before blood culture and 13 cultured directly. Widal result showed that 42 (48.8%) had a titer of 1:160 and above. The disease has the highest rate of occurrence among the females, 18 (18.2%) females were positive as against 8 (8.1%) males and  age group 20-29 years with 12 (13.95%) patients. Overall typhoid prevalence was found to be 26 (30.23%). Out of which, age group 20-29years 12 (13.95%) and adult age group 6 (7%) recorded the highest prevalence respectively. Nine different bacteria genera were isolated from the blood culture, 13 (36.1%) strains of Klebsiella specie was found to be predominant among the gram negative bacteria isolated. The recovered isolates all showed (100%) resistance to ceftazidime (30 µg), augmentin (30 µg) and ampicillin (10 µg), cefuroxime (30 µg) (94.4%), gentamycin (10 µg) (47.2%), ciprofloxacin (5 µg) (25%) and Ofloxacin (5 µg) (25%).  Fourteen (38.9%) of the recovered isolates showed ESBLs patterns. Cefuroxime showed synergism with amoxcillin-clavulanic acid in 8 (57.1%) of the bacteria isolates.

Conclusion: The recovery of gram negative ESBLs bacteria 14 (38.9%) from the blood culture of widal presumptively diagnosed typhoid patients suggests that a laboratory culture proven result is advisable to be the most definitive diagnosis of typhoid fever. We suggest that antibiotic therapy should not be initiated regardless of the widal antibody titre until the blood culture result has proven to be positive for typhoid fever.

Open Access Original Research Article

Fungi Associated with Storage Rots of Colocasia esculenta L. Tubers in Bhubaneswar City, Odisha

Akhtari Khatoon, Ashirbad Mohapatra, Kunja Bihari Satapathy

Microbiology Research Journal International, Page 1-5
DOI: 10.9734/BMRJ/2016/23137

A survey of fungi associated with post-harvest deterioration of Colocasia esculenta L. tubers was conducted in Bhubaneswar city, Odisha, India, in 2014-15. Rotten Colocasia esculenta L. tubers collected from five different markets: Unit-I market, Sahid Nagar, V.S.S. Nagar, Palasuni and Rasulgarh market located in Bhubaneswar city. The following fungi; Aspergillus niger, Aspergillus flavus, Geotrichum candidum, Rhizopus oryzae were isolated from rotten tubers. Of these, Rhizopus oryzae and Geotrichum candidumhas highest percentage frequency of occurrence followed by Aspergillus niger while Aspergillus flavus has the least percentage frequency. Pathogenicity tests revealed that all the isolated fungi were pathogenic on Colocasia esculenta L. tubers; however Rhizopus oryzae and Aspergillus flavus were most pathogenic leading to rapid disintegration of the infected tubers within 20 days of inoculation. While Aspegillus nigerwas the least pathogenic. The use of improved Colocasia esculenta L. varieties, good storage facilities and adequate control measures need to be encouraged in order to reduce storage rot of Colocasia esculenta L. tubers.


Open Access Original Research Article

Bacterial Contamination of Leaf Surfaces of Common Edible Plants in Ebonyi State, South East Nigeria

Ani Ogonna Christiana, Nnamounu Emmanuel Ikechukwu, Onuchkwu Chinedu Christian, Nwabor Ozioma Forstinus, Agah Maduka Victo

Microbiology Research Journal International, Page 1-7
DOI: 10.9734/BMRJ/2016/22391

Aims: This study investigated the bacterial load and isolated the implicated bacteria on the leaf surfaces of Alchornea cordifolia, Musa sapientum and Thaumatococcus danielli in Ebonyi State, South Eastern Nigeria.

Study Design: The research was laboratory-based investigation.

Place and Duration of the Study: The study was carried out at the Department of Microbiology Laboratory, Ebonyi State University, Abakaliki, Nigeria between June 2014 and January 2015.

Methodology: Thirty grams of each sample were washed with 100 ml of physiological saline and inoculated into petri dishes containing a prepared nutrient agar and incubated for 24 hrs at 37°C. The observed bacterial growth were sub-cultured and later subjected to Gram staining and some biochemical tests (indole test, catalase test, oxidase test, motility test, sugar fermentation test).

Results: Staphylococcus spp, E. coli, Salmonella spp, Klebsiella spp and Citrobacter spp were isolated with Staphylococcus spp having the highest percentage occurrence of 38.1% on the three leaf samples followed by E. coli 19.0%, Citrobacter spp 19.0%, Salmonella spp 14.3% and Klebsiella spp 9.5% having the least percentage occurrence. The contamination of these leaves with the isolated organisms may be due to poor handling. The highest count was observed from T. danielli which had a mean plate count of 2.27 x102 while the least plate count 1.98 x102 was from A. cordifolia. M. sapientum, however, showed a plate count of 2.08 x102.

Conclusion: These leaves were heavily contaminated with different bacteria isolates and could serve as vehicles for transmitting pathogenic agents to humans. It is recommended that attention should be channelled towards safeguarding the health of the populace by ensuring the hygienic nature of these leaves from their harvesting, distribution to usage since they are used raw.

Open Access Original Research Article

Correlation between the Prevalence of Hepatitis B and C Viruses against Tumor Necrosis Factor- α among Patients in Babylon Province

Rasha Hadi Saleh, Bara Hamid Hadi

Microbiology Research Journal International, Page 1-10
DOI: 10.9734/BMRJ/2016/22185

Background: Hepatitis is a liver disease caused by infectious and non-infectious agents. Hepatitis B and C are major public health problems worldwide. Hepatitis B (HBV) and C virus (HCV) infections are known to occur in the general population due to their multiple mode of transmission mainly through blood.

Aim: This study aimed to estimate the prevalence of hepatitis B and C virus among population in Babylon province and evaluation of the levels of the TNF-alpha in infected patients with hepatitis B and C

Methods: The study was conduced on individuals referred to the Central Public Health Laboratory to investigate the prevalence of HBV and HCV infections in Babylon province. A total of 6061 samples was included in this study, they screened by VIDAS test for detection of both viruses, then confirmed by real- time PCR. Concentration of TNF- α was measured in patients with hepatitis B and C and control group (Control group consisted of the healthy subjects with no history of renal or liver diseases and negative results for HBV and HCV test) by using ELISA test.

Results: A total of 6061 individual were screened, amongst them, 18 (0.29%) were positive for HBV and 16 (0.26%) were positive for HCV by both VIDS test and real-time PCR.

Most of HBV infections seen among hemodialysis patients followed by haemophila, while most HCV infections seen among thalasemia and haemophila patients than others groups.

The prevalence of both viruses was higher among male than female, and in urban than rural rejoin. Most of HBV infections were high in individual with age ranging between 20-29 and 30-39 years, while most HCV infections in individual with age ranging between 20-29 years, although it is statistically insignificant.

The mean serum level of TNF- α was significantly higher in individual with HBV and HCV infection (68.7±12.84 pg/mL) and (89.1±22.017) as compared with control group (43.1±5.87 pg/mL).

Conclusion: The prevalence of HBV and HCV was relatively low. There are increasing level of TNF-α in the serum of patients with viral hepatitis B and C.