Prediction of rifampicin resistance beyond the RRDR using structure-based machine learning approaches.

Rifampicin resistance is a major therapeutic challenge, particularly in tuberculosis, leprosy, P. aeruginosa and S. aureus infections, where it develops via missense mutations in gene rpoB. Previously we have highlighted that these mutations reduce protein affinities within the RNA polymerase complex, subsequently reducing nucleic acid affinity. Here, we have used these insights to develop a computational rifampicin resistance predictor capable of identifying resistant mutations even outside the well-defined rifampicin resistance determining region (RRDR), using clinical M. tuberculosis sequencing information. Our tool successfully identified up to 90.9% of M. tuberculosis rpoB variants correctly, with sensitivity of 92.2%, specificity of 83.6% and MCC of 0.69, outperforming the current gold-standard GeneXpert-MTB/RIF. We show our model can be translated to other clinically relevant organisms: M. leprae, P. aeruginosa and S. aureus, despite weak sequence identity. Our method was implemented as an interactive tool, SUSPECT-RIF (StrUctural Susceptibility PrEdiCTion for RIFampicin), freely available at https://biosig.unimelb.edu.au/suspect_rif/ .

Effectiveness of topical green tea against multidrug-resistant Staphylococcus aureus in cases of primary pyoderma: An open controlled trial.

BACKGROUND: Antimicrobial activity of green tea against Staphylococcus aureus both in vitro and in vivo has been reported recently. Studies on clinical efficacy and safety of green tea as antibacterial agent against S. aureus in human cases are rare. OBJECTIVES: To evaluate the clinical effectiveness and safety of topical green tea on primary pyoderma caused by S. aureus. We also attempted to determine the minimum inhibitory concentration of green tea against S. aureus and methicillin-resistant S. aureus. METHODS: Open label, prospective, placebo-controlled study included community-acquired primary pyoderma cases caused by S. aureus. Severity grading was done on a scale of 1-5. Green tea ointment 3% and placebo ointment were used. Cure was defined on the basis of negative culture and assessment of clinical improvement. Minimum inhibitory concentration was determined by agar dilution method. Data were analyzed using Statistical Package for Social Sciences (SPSS) software version 16. RESULTS: Of the 372 patients, 250 received green tea and 122 received placebo. Multidrug-resistant S. aureus was isolated in 89.1% in green tea group and 81.1% in placebo group, respectively. Methicillin-resistant S. aureus was isolated in 24 patients. Cure was seen in 86% in green tea group and 6.6% in placebo group which was statistically very significant. The number of days for comprehensive cure in green tea group was 9.2 ± 6.4 days. All patients with methicillin-resistant S. aureus infection in the green tea group were cured. Minimum inhibitory concentration of green tea against S. aureus was 0.0265 ± 0.008 µg/ml and against methicillin-resistant S. aureus was 0.0205 ± 0.003 µg/ml. LIMITATIONS OF THE STUDY: Comparative trial was not conducted in the same patient with different lesions; children less than seven years were not considered as the school authorities did not permit for younger children to be included in the study and true randomization and blinding of investigators were not done. CONCLUSIONS: Green tea has a significant antibacterial effect against multidrug-resistant S. aureus. Minimum inhibitory concentration of green tea is established and is promising in methicillin-resistant S. aureus infections.

Clinico-bacteriological profile of primary pyodermas in Kashmir: a hospital-based study.

Pyodermas are a common group of infectious dermatological conditions on which few studies have been conducted. This study aimed to characterise the clinical and bacteriological profile of pyodermas, and to determine the prevalence of methicillin-resistant Staphylococcus aureus (MRSA) infection in primary pyodermas in a dermatology outpatient department in Kashmir. Methods We conducted a hospital based cross-sectional study in the outpatient Department of Dermatology, Sexually Transmitted Diseases and Leprosy of Shri Maharaja Hari Singh Hospital, Srinagar, Jammu and Kashmir, India. Patients presenting with primary pyodermas were included in the study. A detailed history and complete physical and cutaneous examination was carried out along with microbiological testing to find aetiological microorganisms and their respectiveantimicrobial susceptibility patterns. Antimicrobial susceptibility testing, including that for methicillin resistance, was carried out by standard methods as outlined in the current Clinical and Laboratory Standards Institute guidelines. Results In total, 110 patients were included; the age of the study population ranged from 3 to 65 years (mean age 28 years); 62% were male. Poor personal hygiene was noted in 76 (69%). Furunculosis (56; 51%) was the most common clinical presentation. Staphylococcus aureus was isolated in 89 (81%) of cases, and MRSA formed 54/89 (61%) of Staphylococcus aureus isolates. All MRSA strains were sensitive to vancomycin. Conclusion The prevalence of MRSA was high in this sample of communityacquired primary pyodermas. It is therefore important to monitor the changing trends in bacterial infection and their antimicrobial susceptibility patterns and to formulate a definite antibiotic policy which may be helpful in decreasing the incidence of MRSA infection.

Community acquired multi drug resistant Staphylococcus aureus in a rural setting of North Western Ethiopia: a tough challenge.

Commnunity acquired Methicillin Resistant Staphylococcus aureus species are common causes of skin and soft tissue infections. Foot ulcer of former leprosy patients can be invaded by a multi-microbial infection. Cervicitis is usually caused by certain sexually transmitted agents. Here we report a series of cases of methicillin-resistant Staphylococcus aureus, isolated from two patients presenting with foot ulcer and cervicitis respectively, both in an outpatient or community setting (community onset) in rural North Western Ethiopia. The strains were resistant to all commonly available drugs such as trimethoprim-sulfamethoxazole, ciprofloxacin, erythromycin, chloramphenicol and tetracycline but sensitive to clindamycin. This is the first report of CA-MRSA in the study area.

MRSA--global threat and personal disaster: patients' experiences.

AIM: To ascertain and describe the patients' knowledge, perceptions and experiences of being methicillin-resistant Staphylococcus aureus (MRSA) positive. BACKGROUND: Antibiotic resistant bacteria are a serious global threat. MRSA can cause wound infection, pneumonia, septicaemia and mortality. This qualitative study has focused on patients' experiences of living with MRSA. METHODS: Fifteen patients with MRSA-infected wounds were interviewed. All data were transcribed verbatim and analysed according to content analysis. FINDINGS: Information about the MRSA diagnosis often caused a shock-like reaction. Patients' perception of being MRSA positive was stigmatizing as plague or leprosy; they felt dirty and felt that they were a severe threat to their environment. Fears of infecting someone else and being rejected were commonly expressed. The key findings emerged as a theme: Being exposed to others' shortcomings and being a threat to others' health. Three categories were identified: understanding and emotional reactions, treatment by the healthcare professionals and consequences and expectations. Gaps in both patient and staff knowledge of MRSA led to unnecessary misunderstandings, causing fear, social isolation and suffering. CONCLUSIONS: Living with MRSA can be extremely stressful for the patients. Knowledge and empathy from staff involved in their care is crucial to optimize patients' experiences. Staff education to meet patients' demand for information and prevent contamination is essential.

Fusidic acid in other infections.

Fusidic acid, both systemic and topical, has been used for a wide variety of less common infections. Efficacy for oral fusidic acid has been demonstrated in the treatment of Clostridium difficile colitis and in staphylococcal infections in patients with cystic fibrosis. Topical fusidic acid gel is also effective in bacterial conjunctivitis and other minor external eye infections, and may be effective in reducing bacterial flora in the conjunctival sac prior to eye surgery. Studies suggest a potential role for fusidic acid in neurosurgical prophylaxis, as adjunctive therapy in bacterial endophthalmitis and Legionella pneumonia, and in leprosy. Topical fusidic acid has no effect in the treatment of chlamydial conjunctivitis or the prevention of staphylococcal infections in patients on continuous ambulatory peritoneal dialysis.