Susceptibility of Candida species isolated from immunocompromised patients to antifungal agents

This study was carried out from October 2003 to March 2007 to investigate susceptibility patterns to antifungals of Candida strains isolated from 410 immunocompromised patients in Shiraz, Islamic Republic of Iran. Patients were checked for systemic candidiasis. Fungal colonization was determined and clinical samples collected from those patients with clinical signs of infections were examined. The carbohydrate assimilation patterns of all 354 isolates were studied. Susceptibility of the isolates to antifungal agents was determined using the reference broth microdilution method. Candida Candida albicans was the species most often isolated. Voriconazole was highly active against all the isolates. Major resistance to itraconazole was observed in all Candida spp. Regular investigations into antifungal resistance in medical centres is highly recommended as this will result in more efficient management of invasive candidiasis in immunocompromised patients

Specific PCR assay for rapid and direct detection of Neisseria meningitidis in cerebrospinal fluid specimens

Neisseria meninigitidis is one of the most frequently encountered microorganisms associated with central nervous system infections. The aim of this study was to evaluate a PCR-based assay for specific and rapid detection of N. meninigitidis in CSF specimens. Since April 2002 to July 2006, 130 CSF specimens were collected from patients suspected of having baterial meningitis. Bacterial isolation and identification was carried out according to the standard bacteriological methods. The PCR was used to amplify a 101bp fragment of capsular transport gene A [ctr A] of N. meningitidis. PCR yielded an amplified product with the expected size of 101 base pair fragment. Sensitivity test proved 500 mg of N. meningitidis DNA as the final detection limit and specificity test revealed no cross-reaction for a wide range of respiratory pathogenic organisms. The PCR assay was more sensitive than the bacterial culturing. It might be possible to apply this procedure for rapid diagnosis of meningococci in clinical samples

Association of virulent genes hly, sfa, cnf-1 and pap with antibiotic sensitivity in Escherichia coli strains isolated from children with community-acquired UTI

Recent studies have suggested that the decrease in the pathogenicity of E. coli is due to acquisition of resistance to some antibiotics. This study was performed to investigate four virulence factors of pap, cnf-1, sfa and hly in resistant E. coli and compare them with susceptible strains of the bacteria isolated from children with community-acquired UTI. Drug sensitivity of 96 E. coli isolates was evaluated using a disc diffusion method. The prevalence of virulence genes was determined by PCR. E. coli strains showed a high degree of sensitivity to imipenem, amikacin, nitrofurantoin and ciprofloxacin. Approximately, 80.2% of the isolates were resistant to ampicilin. Only 12.5% of the strains were susceptible to all tested antibiotics. PCR showed that cnf-1 [22.9%] was more prevalent than hly [15.6%] and among adhesion coding genes, pap [30.2%] was more prevalent than sfa [18.8%]. In all strains, the expression of all virulent genes was less prevalent in most antibiotic resistant groups than in susceptible ones but not statistically significant except for genotypes of pap[+]-cnf[+], pap[+]- hIy[+] and cnf[+]-hly[+] with nalidixic acid. We propose that pap and cnf-1 genes in combination with hly gene constitute an uropathogenic genomic configuration which is the characteristic of the nalidixic-acid susceptible E. coli strains, causing urinary tract infection

Pseudomonas aeruginosa: burn infection, treatment and antibacterial resistance

Pseudomonas aeruginosa is an opportunistic pathogen causing severe, acute and chronic nosocomial infections in immunocompromised, catheterized or burn patients. Various types of virulent factors have been identified in P. aeruginosa, suggesting their contribution to the pathogenesis of the disease. The organism is generally resistant to numerous antimicrobial agents due to natural resistance in particular impermeability or mutations and acquisition of resistant determinants. Plasmid and integron have a crucial role in acquisition of mobile elements. Most treatment failures are related to inappropriate initial antibiotic therapy with insufficient coverage of multidrug resistant [MDR] pathogens, the rationale for using combinations of antibiotics to cover MDR gram-negatives. However, clinical data supporting this strategy are limited. In fact, systematic combination therapy may have contributed to the overuse of antibiotics and to the emergence of MDR microorganisms. Nevertheless, combination therapy is the best strategy to treat severe infections due to suspected MDR Pseudomonas. Optimally, therapeutic strategies should be sufficiently broad to cover relevant pathogens while minimizing the risk for emergence of antimicrobial resistance. Polymyxin E [colistin] and carbapenems are the most effective antibiotics against MDR isolates

Helicobacter pylori and extradigestive disorders in the past 10 years

While the association between Helicobacter pylori and other digestive conditions are still under the study, some authors have also investigated an expanding list of the studies on the role of H. pylori as a pathogenic determinant of some extraduodenal idiopathic diseases, such as cardiovascular, immunological, skin, liver, biliary tract, and various other disorders. Although it is still unclear how a localized infection may affect areas distant from the site of infection, it is supposed that H. pylori gastric infection may cause systemic illnesses through immunemediated mechanisms. This idea is based on the following points: [i] local inflammation can have systemic effects; [ii] gastric H. pylori infection is a chronic process that lasts for decades; [iii] persistent infection induces chronic inflammatory and immune responses that can cause lesions that are local or distant from the site of primary infection. In the past 10 years, an increasing number of studies concerning the association between H. pylori infection and extradigestive conditions have been reported. Most of these studies have documented the H. pylori infection by serology and Urease Breath Test [UBT], and rarely by PCR, and no one could isolate any H. pylori microorganism from samples, using culture method. Of course, the culture of this fastidious organism is extremely difficult; if not impossible. In this study, some of the recent papers are reviewed to find new scopes for the role of H. pylori in some kinds of extradigestive diseases

[ prevalence of h serogroups of escherichia coli strains giving rise to acute urinary tract infection in children in Jahrom]

Nowadays E. coli as the most common Cause of acute urinary tract infection are generally named based on serotypes of O and H. The aim of this Cross-Sectional study was to determine the prevalence of H serogroups of E. coli strains that cause community acquired UTI in children. In this study 96 children with urinary tract infections [UTI] referred to two teaching hospitals, in Jahrom, Iran during the period of August 2005- August 2006 were enrolled. Antibiogram was done by disk diffusion method and serotyping by tebe agglutination methods. A Total of 96 E. coli strains were isolated from the urine samples of children with UTI aged from one month to 14 years. Cystitis was diagnosed in 49.2% and pyelonephritis ill 50.8% of these patients. The most resistance was related to Ampicilin [80.2%] and the least to imipenem [1.1%]. The most common type of H antigen was H4 [6.1%]. This is the first report of E-coli serotying in children with UTI from the south of Iran and its relationship with antibiotic resistance and clinical presentation. Further research in athes p ts with move st e thypes is re Commended