A review on most important herbal and synthetic antihelmintic drugs

Parasites and parasitic diseases are widely spread in the world. Their adverse effects on health and social-economic society cause tremendous public health problems. Parasitic infections in different ways (water, soil, food and vegetables) can affect humans and induce other complications such as gastrointestinal disorders, malnutrition, anemia and allergies and sometimes even life threatening. Medicinal plants are being widely used, either as a single drug or in combination with synthetic drugs. These medicinal plants are considered as a valuable source of unique natural products and drugs for development of medicines against various disorders and diseases. In this article the recently published papers about medicinal plants and parasites were reviewed, using scientific sites such as Medline, PubMed and Google Scholar. The used terms included: herbal medicine, medicinal plants, and antihelmintic drugs, antinematoda, anticestoda, antitrematoda. From the above collected literature it might be concluded that these plants are promising potential sources for preparation of new drugs or for pharmacological and therapeutic applications.     

Approaches to serious methicillin-resistant Staphylococcus aureus infections with decreased susceptibility to vancomycin: clinical significance and options for management

PURPOSE OF REVIEW: This review addresses therapeutic approaches to Staphylococcus aureus infections with diminished susceptibility to vancomycin, focusing on recently published data in English language medical literature between June 2006 and July 2007. RECENT FINDINGS: Knowledge regarding the potential limitations of vancomycin therapy for S. aureus infections continues to emerge. Recent changes include alteration of the Clinical Laboratory and Standards Institute vancomycin breakpoint for S. aureus and questions regarding the utility of the lower breakpoint of 2.0 mg/l. Interest continues in the accessory gene regulator (agr) locus and its impact on the activity of vancomycin. Newer options for drug therapy progress, with strengths and limitations becoming more apparent for each. SUMMARY: Newer antimicrobial agents active against methicillin-resistant S. aureus such as daptomycin and linezolid continue to show value. Older antimicrobial agents may play an important therapeutic role and warrant further examination. Work is needed to evaluate current agents against methicillin-resistant S. aureus in the setting of elevated vancomycin minimum inhibitory concentrations or clinical failure. Antimicrobial selection for methicillin-resistant S. aureus infections with reduced susceptibility to vancomycin should be governed by disease severity, susceptibility patterns, knowledge of the limitations of current susceptibility testing, and strengths and weaknesses of the agents being considered.     

Serological assays against Staphylococcus aureus peptidoglycan, crude staphylococcal antigen and staphylolysin in the diagnosis of serious S. aureus infections

Immunoglobulin G antibody levels against Staphylococcus aureus peptidoglycan (PG) and crude staphylococcal antigen (SA) using enzyme-linked immunosorbent assay (ELISA) and antistaphylolysin (ASTA) antibody levels by gel diffusion were determined in 53 patients with S. aureus and 54 patients with non-S. aureus endocarditis and septicemia as compared with 63 febrile control patients. The two ELISAs were the most sensitive assays indicating S. aureus endocarditis in 83% and 88% in the PG- and SA-assays, respectively. 39% of non-S. aureus endocarditis patients were positive in the PG-assay due to antibodies cross-reacting with streptococci. A 100% specificity for S. aureus infections was obtained with the ASTA test, but this assay was less sensitive. A significant rise in anti-PG or anti-SA antibody levels was not only seen among S. aureus infections but also in some streptococcal and S. epidermidis infections as well as in 3 febrile control patients. When at least 2 of the 3 assays showed positive peak antibody levels 1-4 weeks after onset of infection together with a significant rise of both anti-PG and anti-SA antibody levels the S. aureus endocarditis diagnosis was highly suggestive. Thus, we recommend the combined use of these 3 assays using paired serum samples in diagnosing serious S. aureus infections.     

Controlling the usage of intranasal mupirocin does impact the rate of Staphylococcus aureus deep sternal wound infections in cardiac surgery patients

BACKGROUND: Staphylococcus aureus (S aureus) is the major cause of surgical site infections (SSI). At The Christ Hospital, Cincinnati, OH, S aureus accounted for over 80% of sternal wound infections in cardiac surgery patients. Approximately 700 cardiac surgeries are performed each year, with an associated infection rate of 1.8% per 100 procedures performed. In an attempt to reduce S aureus sternal wound infections, the use of prophylactic intranasal mupirocin was examined. METHODS: Each patient undergoing cardiac surgery was nasally cultured before entering the operating room, and then intranasal mupirocin was applied and continued every 12 hours. Culture results were finalized within 48 hours. Mupirocin was discontinued when the culture returned negative and continued for 7 days when the culture returned positive for S aureus. RESULTS: Cultures showed a S aureus carrier rate of 21%. These patients received mupirocin for 7 days. A decrease in S aureus-associated SSI rates was observed from a case rate of 1.68% to 0.37% per 100 procedures over a 17-month period. CONCLUSION: Identifying and treating S aureus carriers with a full course of mupirocin does impact the rate of S aureus surgical site infections.     

A critical review of oxazolidinones: An alternative or replacement for glycopeptides and streptogramins?

OBJECTIVE: To review the available data on the oxazolidinones linezolid and eperezolid. DATA SELECTION: Published reports were obtained by searching MEDLINE for articles published between 1992 and 2000, inclusive. References of published papers were also obtained and reviewed. Abstracts from scientific proceedings were reviewed. DATA EXTRACTION: Due to the limited data available regarding these agents, the criteria for study inclusion were not restrictive. DATA SYNTHESIS: The oxazolidinones (eg, linezolid) are a new antimicrobial class with a unique mechanism of action. They are active against resistant Gram-positive cocci including methicillin-susceptible and -resistant Staphylococcus aureus (MRSA), methicillin-susceptible and -resistant Staphylococccus epidermidis, vancomycin-resistant enterococci (VRE) and penicillin-resistant Streptococcus pneumoniae (PRSP). Linezolid is active against anaerobes and displays modest activity against fastidious Gram-negative pathogens such as Haemophilus influenzae, but is not active against Enterobacteriaceae. Linezolid is available both orally and parenterally, and has a bioavailability of 100%. Clinical trials comparing linezolid with standard therapy have demonstrated similar bacteriological and clinical cures rates to standard therapy in community- and hospital-acquired pneumonia, uncomplicated and complicated skin and soft tissue infections, and infections caused by MRSA and VRE. Adverse effects have been minor and infrequent; however, platelets should be monitored in patients who have received more than two weeks of linezolid therapy. It is expected that these agents will have a bright future due to their excellent spectrum of activity against antibiotic-resistant Gram-positive organisms, such as MRSA, VRE and PRSP, and their excellent bioavailability. CONCLUSION: The oxazolidinones represent a new class of antimicrobials with a unique mechanism of action. They have excellent activity against susceptible and resistant Gram-positive organisms such as MRSA, methicillin-susceptible S epidermidis, VRE and PRSP, and a good adverse effect profile; they can be administered both intravenously and orally. Their potential use in Canada may be as an intravenous and oral alternative to glycopeptides and streptogramins.     

Diagnosis and management of Staphylococcus aureus infections of the skin and soft tissue

Infections involving the skin and soft tissue are common and range from superficial, localized and sometimes self-limiting infections to deep, rapidly spreading and potentially life-threatening infections. Skin infections caused by Staphylococcus aureus include primary pyodermas, while those involving the soft tissues include cellulitis and pyomyositis. Surgical site infections and infections in intravenous drug users are also commonly caused by S. aureus. The severity of the infection determines the choice of treatment. There are few studies that have critically appraised the use of antibiotics in skin and soft tissue infections, and most guidelines are based on expert opinion. The beta-lactam group of antibiotics are the mainstay of treatment for methicillin-susceptible S. aureus infections. For methicillin-resistant S. aureus (MRSA) infections, both with community-acquired and hospital-acquired strains--which are becoming an increasing problem--the antibiotic choice is determined by local susceptibility patterns. Macrolides, clindamycin and cotrimoxazole are options for community-acquired MRSA, while vancomycin is reserved for treatment of infections caused by multiresistant MRSA strains and for patients with suspected endocarditis or severe sepsis. Although a number of the newer antibiotics such as linezolid and quinopristin/dalfopristin have been shown to have good activity against MRSA, these agents should only be used with specialist advice.     

Recent advances in the treatment of infections due to resistant Staphylococcus aureus

PURPOSE OF REVIEW: This paper reviews recent data on the treatment of infections caused by drug-resistant Staphylococcus aureus, particularly methicillin-resistant S. aureus (MRSA). This review will focus on new findings reported in the English-language medical literature from June 2003 to September 2004. RECENT FINDINGS: Despite the emergence of resistant and multidrug-resistant S. aureus, we have three effective drugs in clinical use for which little resistance has been observed: quinupristin-dalfopristin, linezolid, and daptomycin. Linezolid looks particularly promising in the treatment of MRSA pneumonia. Daptomycin displays rapid bactericidal activity in vitro, but, so far, clinical trials have only been conducted for the treatment of skin and soft-tissue infections. There are three drugs with broad-spectrum activity against Gram-positive organisms at an advanced stage of testing: two new glycopeptides with potent bacteriocidal activity and long half-lives (oritavancin and dalbavancin), and tigecycline, a minocycline derivative. These drugs have also shown efficacy in the treatment of skin and soft-tissue infections. SUMMARY: The promising data that have emerged in the last year indicate that we may have six available drugs to treat resistant S. aureus infections within the next few years. The next goal is to determine the appropriate indications and cost-effectiveness of each of these drugs in our treatment strategy against S. aureus and other Gram-positive pathogens.     

A new serological assay for Staphylococcus aureus infections: detection of IgG antibodies to S. aureus lipase with an enzyme-linked immunosorbent assay

Purified Staphylococcus aureus lipase was used as antigen in an enzyme-linked immunosorbent assay (ELISA) that detected IgG antibodies in 169 patients with infections due to S. aureus, in 122 patients with infections not due to S. aureus, and in 167 healthy controls. Eighty-eight percent (21 of 24) of the patients with endocarditis due to S. aureus showed a positive level of antibody to lipase or a significant change in antibody titer during the first month, as did 89% (17 of 19) and 28% (5 of 18) of the patients with complicated and uncomplicated septicemia due to S. aureus, respectively. The specificity for S. aureus infections was high; only one patient in the non-S. aureus endocarditis and septicemia groups showed a significant rise in antibody titer, and this rise did not reach a positive antibody level. Patients with recurrent furunculosis or chronic osteomyelitis due to S. aureus responded in only 15% and 23% of cases, respectively. We suggest that the antibody-to-lipase ELISA could be used as a valuable complement to other serological assays in diagnosing serious S. aureus infections because of its high sensitivity and specificity.     

Traditional use of medicinal plants for anti-ringworm therapy in some parts of Kamrup District of Assam,a North Eastern State of India

ObjectiveTo survey traditional use of medicinal plants for anti-ringworm therapy from December 2007 to January 2009 in some parts of Kamrup district of Assam, a North Eastern State of India.MethodsBased on a standard questionnaire, local inhabitants were interviewed for their knowledge of medicinal plants used against ringworm. Each entry includes the botanical and prevalent local name(s), part(s) used, and mode of use against the diseases.ResultsThis report deals with 46 plant species belonging to 30 different families used as herbal remedies for the treatment of Dermatophytosis.ConclusionsThe study reveals several medicinal plants used by the local people for the treatment of cutaneous infections caused by dermatophytes. Such study may lead to the discovery of new antifungal agents from natural sources.     

Staphylococcal infections in PD: monitoring, screening and prevention

Peritonitis and catheter infections remain a major complication of peritoneal dialysis, accounting for much of the morbidity associated with the technique. The most common source of infection is contamination with predominantly Gram positive skin flora, Staphylococcus (S) epidermidis and S. aureus. The aims of this study were, (a) to determine the incidence of S. aureus and S. epidermidis infections in the unit, (b) to examine whether treatment of S. aureus carriers may reduce the incidence of exit site infection and (c) to examine whether improving patient education may reduce S. epidermidis peritonitis rate.     

Staphylococcal bacteremia in a "Germ-free" unit.

The rate of carriage and infections due to strains of Staphylococcus aureus were evaluated in adults with acute leukemia in isolators characterized by laminar air flow and barrier isolation. Patients were randomly given antimicrobial prophylaxis with oral nonabsorbed antibiotics and a nasal antibiotic ointment. In four years S aureus was isolated from the nostrils or other sites in 36 patients. Persistent isolation was noted in 24 patients. Suppression of gut flora was associated with a higher carriage rate of S aureus. Five episodes of bacteremia due to S aureus occurred at the nadir of leukopenia induced by chemotherapy. Death occurred within five days in the three patients whose peripheral white blood cell count did not rise. Patient isolation and suppression of gut flora helped reduce infections due to Pseudomonas sp and fungi, but S aureus emerged as a life-threatening pathogen.     

Natural products:Perspectives in the pharmacological treatment of gastrointestinal anisakiasis

Objective: To evaluate the activity of different natural products against L3 larvae of Anisakis type I. Methods: Information on investigations into the activity of natural products against the L3 larvae of Anisakis simplex was collected from scientific journals, books, theses and reports via a library and electronic search(using Pubmed, Scopus, Medline, Web of Science and Science Direct). The search terms included: natural products, medicinal plants, essential oils, terpenic derivatives, Anisakis, antinematodal activity. Results: In the literature reviewed numerous papers were found concerning the in vitro and in vivo activity against Anisakis type I of various natural products(plant extracts, essential oils and their major components). Analysis of the results showed that in vitro tests the Melaleuca alternifolia essential oil and the ar-turmerone isolated from Curcuma longa displayed the greatest activity. In vivo, the most active compound was perillaldehyde, the main component of Perilla frutescens essential oil. Conclusions: This study shows that some natural products exhibited promising antianisakis properties.     

Infections of cardiac implantable electronic devices: a retrospective multicenter observational study

Infections of cardiac implantable electronic devices (CIED) can cause significant morbidity, mortality, and financial burden. Although staphylococcal organisms account for most infections of these cardiac devices, approximately 20% of all CIED-related infections are caused by non-Staphylococcus species. Herein we describe and compare the demographics, clinical presentation, and outcomes of Staphylococcus aureus and non-staphylococcal infections of CIED.We performed a retrospective, multicenter, observational study of patients from 4 academic hospitals in Houston between 2002 and 2009. All 80 identified non-staphylococcal CIED-related infections were matched, at a 1:1 ratio, to S. aureus infections.Although the demographics and general comorbidities in the 2 study groups were relatively similar, the S. aureus group had a higher proportion of patients with coronary artery disease, diabetes mellitus, and end-stage renal disease. Additionally, 81% of S. aureus compared with only 48.5% of the non-staphylococcal CIED-related infections were health care-associated (p < 0.001). Furthermore, when compared to non-staphylococcal infections, the S. aureus group had more indwelling intravascular foreign material (p < 0.001), more rapid clinical progression (p < 0.001), and overall worse clinical presentation (p < 0.001). However, after stratifying by clinical presentation, the mortality rates in the 2 groups were similar (p = 0.45).Since approximately one-fifth of all CIED-related infections are caused by non-staphylococcal organisms, and untimely antibiotic treatment can result in serious complications, it may be prudent to broaden empiric antimicrobial therapy to cover both Gram-positive and -negative bacteria, until the causative organism is identified.     

Rifampin resistance. Development during the therapy of methicillin-resistant Staphylococcus aureus infection

The incidence of methicillin-resistant staphylococcal infections, for which vancomycin hydrochloride remains the only active cell-wall antibiotic therapy, is rising. Some physicians have been combining other antibiotics with vancomycin in hopes of obtaining a more effective regimen for the therapy of these infections. Rifampin has been advocated as a concurrent second antibiotic because of its extraordinary potent bactericidal activity for Staphylococcus aureus. When rifampin is used in combination with a cell-wall antibiotic, suppression of the development of rifampin resistance has been thought possible. We report a case of infection caused by a methicillin-resistant S aureus in which the rifampin resistance occurred during therapy with vancomycin and rifampin. The rifampin resistance was stable and was present after ten serial broth and agar passages. Physicians are cautioned against the indiscriminant or routine use of rifampin as a second antibiotic in combination with vancomycin for the therapy of infections caused by S aureus.     

Process improvement plan for the reduction of sternal surgical site infections among patients undergoing coronary artery bypass graft surgery

In an attempt to reduce sternal infections caused by Staphylococcus aureus, a protocol was introduced that included the administration of intranasal mupirocin calcium 2% before surgery to patients undergoing cardiothoracic surgery. Surveillance data indicated a 55% reduction in the rate of deep sternal wound infections caused by S aureus and superficial sternal wound infections have declined from 25 to 6 since the adoption of the protocol. At the study institution, this protocol is now an ongoing process to reduce the incidence of sternal infections caused by S aureus among cardiothoracic patients.     

Treatment of community-acquired methicillin-resistant Staphylococcus aureus in children

PURPOSE OF REVIEW: The concept of methicillin-resistant Staphylococcus aureus (MRSA) associated with broad resistance, nosocomial acquisition, and known risk factors has recently been expanded. A new type of MRSA that is resistant to fewer antibiotics has emerged in pediatric practice since the mid-1990s. These isolates are community acquired and have been reported from diverse geographic regions. Awareness of these organisms is important for appropriate treatment of S. aureus infections in children. RECENT FINDINGS: Community-acquired MRSA (CA-MRSA) isolates are similar in many respects to community-acquired methicillin-susceptible S. aureus (CA-MSSA). There are usually no differences in risk factors between children with CA-MRSA infections and those with CA-MSSA infections or their household contacts. In one study, however, multivariate analysis showed that age greater than 1 year and health care contact in the preceding month were significant risk factors for CA-MRSA. Skin and soft tissue infections are the most common manifestations, although serious invasive infections and death may occur. Pneumonia has been reported more often in children with CA-MRSA than in those with CA-MSSA. Clindamycin is an effective therapy for CA-MRSA, but there is a risk for development of clindamycin resistance during treatment of a CA-MRSA that is clindamycin susceptible and inducibly erythromycin resistant. Trimethoprim-sulfamethoxazole is likely to be effective, and linezolid is a new option for treatment. SUMMARY: The appearance of CA-MRSA has important implications for therapy of infections caused by S. aureus in children. Three specific issues are the development of resistance during clindamycin therapy, insufficient data on the use of trimethoprim-sulfamethoxazole in serious CA-MRSA infections, and the appropriate role for newer antibiotics such as linezolid.     

Experimental protection of mice against lethal Staphylococcus aureus infection by novel bacteriophage phi MR11

The protective effects of bacteriophages were assessed against experimental Staphylococcus aureus infection in mice. Of the S. aureus phages isolated in the study, phi MR11 was representatively used for all testing, because its host range was the most broad and it carries no genes for known toxins or antibiotic resistance. Intraperitoneal injections (8 x 10(8) cells) of S. aureus, including methicillin-resistant bacteria, caused bacteremia and eventual death in mice. In contrast, subsequent intraperitoneal administration of purified phi MR11 (MOI > or = 0.1) suppressed S. aureus-induced lethality. This lifesaving effect coincided with the rapid appearance of phi MR11 in the circulation, which remained at substantial levels until the bacteria were eradicated. Inoculation with high-dose phi MR11 alone produced no adverse effects attributable to the phage. These results uphold the efficacy of phage therapy against pernicious S. aureus infections in humans and suggest that phi MR11 may be a potential prototype for gene-modified, advanced therapeutic S. aureus phages.     

Analysis of genetic diversity among Staphylococcus aureus isolates from patients with deep-seated and superficial staphylococcal infections using pulsed-field gel electrophoresis

Molecular typing was performed to reveal the genetic diversity among Staphylococcus aureus strains causing deep-seated versus superficial staphylococcal infections. Pulsed-field gel electrophoresis with cluster analysis, plasmid and antimicrobial susceptibility profiling of 50 S. aureus strains collected from these 2 groups of patients were undertaken. A total of 19 (designated A through S) distinct genotypes were identified by PFGE of Sma I-digested genomic DNA. The most prevalent PFGE type was L, which accounted for 30% of isolates and was detected among superficial isolates only. The second most prevalent PFGE type, type A (18%), was predominant among deep-seated isolates. Remaining PFGE types varied in distribution between the 2 groups. Plasmid profile analysis revealed that deep isolates harbour plasmids more frequently (comprising 64% of isolates) than superficial isolates (4%) and showed 10 and 2 distinct patterns, respectively, with pattern 1 being the dominant among deep isolates. Antimicrobial susceptibility data suggested an increased prevalence of antibiotic resistance among deep isolates with the majority (40%) exhibiting identical antibiograms compared to superficial isolates. No resistance was detected against clindamycin and vancomycin. The results of our study indicate a previously unrecognized dichotomy of S. aureus strains, causing deep-seated and superficial infections.     

Synergy in a medicinal plant: antimicrobial action of berberine potentiated by 5'-methoxyhydnocarpin, a multidrug pump inhibitor

Multidrug resistance pumps (MDRs) protect microbial cells from both synthetic and natural antimicrobials. Amphipathic cations are preferred substrates of MDRs. Berberine alkaloids, which are cationic antimicrobials produced by a variety of plants, are readily extruded by MDRs. Several Berberis medicinal plants producing berberine were found also to synthesize an inhibitor of the NorA MDR pump of a human pathogen Staphylococcus aureus. The inhibitor was identified as 5'-methoxyhydnocarpin (5'-MHC), previously reported as a minor component of chaulmoogra oil, a traditional therapy for leprosy. 5'-MHC is an amphipathic weak acid and is distinctly different from the cationic substrates of NorA. 5'-MHC had no antimicrobial activity alone but strongly potentiated the action of berberine and other NorA substrates against S. aureus. MDR-dependent efflux of ethidium bromide and berberine from S. aureus cells was completely inhibited by 5'-MHC. The level of accumulation of berberine in the cells was increased strongly in the presence of 5'-MHC, indicating that this plant compound effectively disabled the bacterial resistance mechanism against the berberine antimicrobial.