eBooks de Microbiología, página 2 de 4

Prevalence of group B streptococcus in pregnant women attending a tertiary hospital in Ghana in 2001.

Carbapenem resistant Acinetobacter baumannii, especially the metallo beta lactamase (MBL) positive ones, are fast coming up the list of pathogens causing nosocomial infections. Thus it should be a present day concern of all tertiary care hospitalto detect the presence of MBL positive Acinetobacter baumannii.Aims: To determine the presence and extent of MBL positive Acinetobacter bauman-nii group.

Pseudomonas aeruginosa infection is a serious problem in patients hospitalized with cancer, cystic fbrosis (CF) and in intensive care units (ICUs). Twitch-ing motility contributes to the virulence of P. aeruginosa and permits colonization and infection of the respiratory tract. Genetic relatedness and cross-infection by multidrug-resistant (MDR) P. aeruginosa could be identifed by the random ampli-fed polymorphic (RAPD) PCR genotypic identifcation system.

Owing to the inability of real-time polymerase chain reaction (PCR) to distinguish between signals originating from viable cells and DNA released from dead cells, (i.e. it can detect dead cells) a risk exists that DNA from dead cells can result in false-positive PCR signals, so it is important to use a proper method for sterilization to maintain the accuracy of the quantitative real-time PCR assay.

Shigatoxigenic Escherichia coli strains are major food-borne pathogens that are trans-mitted through contaminated meat and meat products. Apart from cattle, sheep and goat are important natural reservoirs. Faecal contamination during slaughter and fur-ther processing along with poor hygienic practices accounts for the presence of STEC in raw meat. A total of 200 samples (50 each of mutton and chicken and 50 samples each of mutton and chicken swabs) collected from various sources were subjected to PCR analysis for the presence of Shigatoxigenic E. coli using primers specifc to STEC virulent genes, shiga toxin (stx1 and stx2) and enterohaemolysin (hlyA) with amplif-cation size of 614bp, 779bp and 361bp respectively. Out of 200 samples, 58 showed presence of STEC (20 mutton, 24 mutton swabs, 7 chicken and 7 chicken swabs out of 50 samples each). Of the 58 STEC positive samples, 42 (72.4%) showed presence of stx1, 16 (27.5%) showed stx2, 21 (36.2%) showed hlyA gene and 8 (13.7%) showed both stx1 and stx2. Among 58 STEC positive isolates, 8.6% (1 mutton, 2 mutton swab and 2 chicken swabs) isolates were possessing all the 3 virulent genes. The sensitivity of PCR method for STEC was 1.7cfu. Enrichment with mTSB broth containing novo-biocin gave good results compared to mEC broth with novobiocin. It is advisable to use more rapid, sensitive and specifc PCR method to detect virulent STEC from diferent food sources.

Ascites can present a challenging diagnostic problem. Bacteria caus-ing spontaneous bacterial peritonitis (SBP) may difer in patients with and without underlying malignancies. To date, reports focusing on patients with malignancies and ascites are less. The aim of the present study was to determine the prevalence and causative agents of SBP in cancer and non cancer patients and the antibacte-rial susceptibilities of these microorganisms. Also, to identify diferences, if any, in polymorphonuclear (PMN) cell count, interleukin (IL)-6 concentration, and diferent biochemical diagnostic parameters, we analyzed for infected and non infected as-cites in both groups.

Approximately 60% of emerging human pathogens are zoonoses. The complex na-ture of the human-animal interface is constantly infuenced by the efects of climate change, anthropogenic and natural factors. Geoclimatic change most markedly af-fects zoonotic diseases transmitted by arthropod vectors. Travel, tourism and trade are the major human factors impacting the epidemiology of zoonotic diseases. The re-emergence of zoonotic diseases is also driven by pathogen adaptation and ani-mal migration. All these factors converge to make zoonotic diseases such as West Nile fever and Lyme disease of great public health concern in the developed world. However, the efects of climate change are predicted to be worse for the developing world where challenging socioeconomic and political environments are exacerbated by a lack of epidemiological studies on zoonotic diseases.

Infections due to gram-negative bacilli are common in cancer pa-tients during aggressive therapy. The presented study determined the microbial spectrum and antimicrobial susceptibility of gram-negative bacteria isolated from various infection sites in hospitalized cancer patients in Egypt.

Cryptococcal meningitis has become the most common lethal opportunistic fungal infection in people with HIV and AIDS. Prompt treatment depends on awareness of the common symptoms. The purpose of this study was to identify factors associated with Cryptococcus meningitis in HIV infected patients in Kisumu District.

Managing bacteria and their bioflms in wounds is vital in achieving wound healing. Determination of antimicrobial and antibioflm activity of diferent remedies such as dexpanthenol and propolis- natural bee product- alone and/or in combination with topical antimicrobial agents on Pseudomonas and Staphylococcus wound infection was the aim of the this study.

Nowadays, the diagnosis of echinococcus infection with multiple organs involvement is not frequent in clinical practice. We report the case of a 35- year-old woman admitted to the Imam Khomeini Hospital with simultaneous liver and lung cysts. In endemic areas, workup of echinococcal infection should be considered when a patient presents with cystic lesions of multiple organs.

Hypersensitivity to Anisakis species is a worldwide medical problem. The aim of this study was to detect the immunological response in experimental mice, through measurement of Immunoglobulin E (IgE) antibodies in their lympho-cytes by fow cytometry, following the ingestion of Anisakis crude antigen.

Diagnosis of hepatitis C virus (HCV) infection routinely performed in the microbiology laboratories is based on the detection of serum antibodies against hepatitis C virus (anti-HCV) by two main methods: enzyme immunoassay (EIA) and chemiluminescence immunoassay (CIA). Diferent reactives built on these two methods were manufactured and are still in use for the diagnosis of HCV infections. The most common problem in the laboratory screening assay of anti-HCV is the false positivity of low titers. A confrmatory test is needed to discriminate the false positive results from the accurate ones. A lot of discussions focused on deciding a reliable, easy-to-use and cost-efective confrmative test method in order to check and confrm the results of anti-HCV reactives routinely used in the detection of serum anti-HCV level.

Over the past decade, an increasing trend in vancomycin minimum inhibitory concentration (MIC) levels for methicillin resistant Staphylococcus aureus (MRSA) and methicillin-sensitive S. aureus has been reported. The phenomenon has been a topic of great interest in light of limited new and novel antimicrobial therapy in recent years. The goals of this study were to examine the relationship between high vs. low vancomycin MIC and patient outcomes, to assess the usage of vancomy-cin over time, and to determine whether an increase in vancomycin MIC had occurred among MRSA clinical isolates over time.

Antimicrobial susceptibility testing was performed on a total of 253 [203 shiga toxin-producing Escherichia coli (STEC) and 50 non-STEC] Escherichia coli isolates from difer-ent raw meats, RTE meat foods, drinking water and human diarrhoeic samples in Pun-jab, India. Among the 20 antimicrobial agents tested, resistance was most frequent for penicillin (253/253, 100%) followed by linezolid (249/253, 98.4%), erythromycin (245/253, 96.8%), streptomycin (232/253, 91.7%), tetracycline (223/253, 88.1%), am-picillin 123/253,48.2%), cephotaxime (106/253,41.9%), trimethoprim (93/253, 36.8%)), co-trimoxazole (85/253, 33.6%), cefaclor (84/253, 33.2%), amoxycillin (79/253, 31.3%), ciprofoxacin (78/253, 30.8%), kanamycin (76/253, 30.0%), norfoxacin (62/253, 24.5%), ofoxacin (60/253, 23.7%), chloramphenicol (35/253, 13.8%), Polymyxin-B (27/253, 10.6%), colistin (25/253,9.9%), amikacin (22/253, 8.7%) and gentamycin (17/253, 6.7%). Out of 203 STEC isolates 73 (35.9%) showed resistance to more than 50% of the anti-biotics tested. Only one isolate from pork showed resistance to 90% of the antibiotics tested. Cluster analysis also revealed that human isolates were diferent from other E. coli isolated from meat and meat products sources. The distribution of resistance determinants for tetracycline and streptomycin was assessed by PCR in resistant iso-lates. The most common resistance determinants were tetA (60%) and tetB (27%). Forty seven per cent of the isolates contained both strA and strB genes, 33% and 10% isolates carried strA and strB genes, respectively and 10% of isolates did carry neither strA nor strB. Cloning and sequencing of tetA and tetB genes of O69 shiga toxin-pro-ducing E. coli isolate from bufalo meat showed 99-100% homology with published sequences of related isolates in GenBank. Antibiotic susceptibility studies revealed that meat, RTE meat products, drinking water and human diarrhoeic samples from Punjab, India contains multiple drug resistant strains of E. coli which may serve as a reservoir for antibiotic resistance genes in the food environment and may transmit to humans through food chain.

Owing to the inability of real-time polymerase chain reaction (PCR) to distinguish between signals originating from viable cells and DNA released from dead cells, (i.e. it can detect dead cells) a risk exists that DNA from dead cells can result in false-positive PCR signals, so it is important to use a proper method for sterilization to maintain the accuracy of the quantitative real-time PCR assay.

A 24-year-old man, injection drug user (IDU) and HIV-positive was admitted to the Infectious Department of Imam Khomeini Hospital in February 2010, with a history of two months of malaise, night sweating and weight loss. He complained of fever and chills. On examination, pale conjunctivae and a palpable spleen were the only remarkable clinical fndings. PPD skin test was not reactive and chest X-ray was also normal. Abdominal CT scan revealed multiple hypodense regions suggestive for splenic abscesses. Diagnostic laparatomy and splenectomy were performed. Defnite tuberculosis infection became evident after that Ziehl- Neelsen staining of the infammated tissue was performed and suspected acid-fast bacilli of Mycobacterium tuberculosis were detected under microscopy. Consecutively, the tuberculostatic treatment including isoniazid (300 mg daily), rifampicin (600 mgr daily), ethambutol (800 mgr daily) and pyrazinamide (1000 mgr daily) were initiated; He eventually began to improve and the fever resolved within 10 days.

Afatoxin exposure has been shown to cause cell-mediated immune suppression and enhance HIV viral replication. Such immune suppression from afa-toxin can impair resistance to both infectious diseases

Clindamycin (Cd) is one of the important alternative antibiotics in the therapy of Staphylococcus aureus, particularly in methicillin resistant Staphylococcus aureus (MRSA). Without the double-disk test, all the Staphylococcus aureus isolates with in-ducible Cd would have been misclassifed as Cd susceptible, resulting in an underes-timated Cd resistance rate. We report a Cd clinical failure where resistance developed on therapy in D-test-positive MRSA strains. The D-test identifes inducible resistance that might presage mutational Cd resistance which can be either constitutive or inducible. The present study was aimed to know the prevalence and phenotypic characterization of induced Cd resistance in MRSA isolates from hospital patients of various medical wards, surgical wards, diabetic care centres and intensive care units (ICU) of diferent corporate hospitals of Coastal Andhra Pradesh, South India. The specimens were collected from various body fuids and swabs of patients;- blood (n=29), urine (n=50), pus(n=45), nasal swabs (n=40), respiratory tract swabs (n=40), eye swabs (n=50), ear swabs (n=89), and skin infection swabs (n=80). These samples were tested for the presence of MRSA and screening was done by Oxacillin discs. Out of the 153 coagulase positive Staphylococcus aureus isolates, 82 were MRSA. Eryth-romycin (Ery) resistance was observed in 23 isolates which expressed Cd inhibitory activity and one isolate was resistant to both Cd and Ery. The present study showed high level of multidrug resistance among MRSA and high incidence of Ery induced Cd resistance is also observed. Hence, it is advisable to include inducible Cd resistance testing as a part of routine antibiotic susceptibility as it may be missed in routine antibiotic testing to avoid treatment failure.

UTI is an important cause of morbidity in pediatric population; early diagnosis and appropriate treatment is essential in order to avoid long term com-plications. Therefore this study was done to estimate the magnitude of UTI among febrile children attending Bugando Medical Centre and also to provide the insight on treatment options and sensitivity of diagnostic tests.