RESUMO
Cognitive impairment is not uncommon in patients with end-stage renal disease and can make it more difficult for these patients to carry out peritoneal dialysis (PD) on their own. Their attempts to do so may result in adverse consequences such as peritonitis. PD exchange is a complex procedure demanding knowledge and skill which requires close supervision and guidance by a renal nurse specialist. In this study, a non-immersive virtual reality (VR) training program using a Leap motion hand tracking device was developed to facilitate patients' understanding and learning of the PD exchange procedure before attempting real task practice. This study was a two-center single-blinded randomized controlled trial on 23 incident PD patients. Patients in the experimental group received 8 sessions of VR training, while patients in the control were provided with printed educational materials. The results showed that there were significant differences between the two groups in performance of the overall PD exchange sequence, especially on the crucial steps. VR had a patient satisfaction rate of 89%, and all patients preferred to have the VR aid incorporated in PD training. Our findings conclude VR can be a useful aid in the training and reinforcement of PD exchange procedures, with distinct merits of being free from restrictions of time, space, and manpower.
RESUMO
The American College of Cardiology/American Heart Association released guidelines for the prevention, detection, evaluation, and management of high blood pressure (BP) in adults in 2017. In 2018, the European Society of Cardiology (ESC)/European Society of Hypertension (ESH) published new guidelines for the management of arterial hypertension. Despite the many similarities between these two guidelines, there are also major differences in the guidelines in terms of diagnosis and treatment of hypertension. A working group of the Hong Kong College of Physicians (HKCP) convened and conducted a focused discussion on important issues of public interest, including classification of BP, BP measurement, thresholds for initiation of antihypertensive medications, BP treatment targets, and treatment strategies. The HKCP concurs with the 2018 ESC/ESH guideline on BP classification, which defines hypertension as office systolic BP ≥140 mm Hg and/or diastolic BP ≥90 mm Hg. The HKCP also acknowledges the growing evidence of home BP monitoring and ambulatory BP monitoring in the diagnosis and monitoring of hypertension and endorses the wider use of both methods. The HKCP also supports the direction of a risk-based approach for initiation of antihypertensive medications and the specification of a treatment target range for both systolic and diastolic BP with consideration of different age-groups and specific disease subgroups. Non-pharmacological interventions are crucial, both at the societal and individual patient levels. The recent guideline publications provide good opportunities to increase public awareness of hypertension and encourage lifestyle modifications among the local population.
Assuntos
Cardiologia/normas , Hipertensão , Guias de Prática Clínica como Assunto , American Heart Association , Hong Kong , Humanos , Sociedades Médicas , Estados UnidosRESUMO
AIM: The aim of this study was to evaluate the validity, reliability and sensitivity of the disease-specific items of the Kidney Disease Quality of Life-36 (KDQOL-36) in Chinese patients undergoing maintenance dialysis. METHODS: The content validity was assessed by content validity index (CVI) in ten subjects. 356 subjects were recruited for pilot psychometric testing. The internal construct validity was assessed by corrected item-subscale total correlation. Confirmatory factor analysis (CFA) was used to confirm the factor structure. The convergent validity was assessed by Pearson's correlation test between the disease specific subscale scores and SF-12 version 2 Health Survey (SF-12 v2) scores. The reliability was assessed by the internal consistency (Cronbach's Alpha coefficient) and 2-week test-retest reliability (intraclass correlation coefficient (ICC)). The sensitivity was determined by performing known group comparisons by independent t-test. RESULTS: The CVI on clarity and relevance was ≥ 0.9 for all items. Corrected item- total correlation scores were ≥0.4 for all, except an item related to problems with access site. CFA confirmed the 3-factor structure of the disease-specific component of the KDQOL-36. The correlation coefficients between the disease-specific domain scores and the SF-12 v2 physical and mental component summary scores ranged from 0.328 to 0.492. The reliability was good (Cronbach's alpha coefficients ranged from 0.810 to 0.931, ICC ranged from 0.792 to 0.924). Only the effect subscale was sensitive in detecting differences in HRQOL between haemodialysis and peritoneal dialysis patients, with effect size = 0.68. CONCLUSION: The disease-specific items of the KDQOL-36 are a valid, reliable and sensitive measure to assess the health-related quality of life of Chinese patients on maintenance dialysis.
Assuntos
Povo Asiático/psicologia , Nefropatias/psicologia , Qualidade de Vida/psicologia , Diálise Renal/psicologia , Adulto , Análise Fatorial , Feminino , Inquéritos Epidemiológicos/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Psicometria/métodos , Reprodutibilidade dos Testes , Inquéritos e QuestionáriosRESUMO
We report a 38-year-old Chinese woman with lupus nephritis on peritoneal dialysis and long-term maintenance steroid therapy. This patient developed paradoxical deterioration during anti-tubercular therapy for tuberculous lymphadenitis. The deterioration resolved spontaneously without change to pharmacotherapy. Paradoxical deterioration that may spontaneously resolve is a potential complication of anti-tubercular treatment in patients on long-term renal replacement therapy.
Assuntos
Corticosteroides/uso terapêutico , Antituberculosos/efeitos adversos , Nefrite Lúpica/terapia , Diálise Peritoneal Ambulatorial Contínua , Tuberculose dos Linfonodos/tratamento farmacológico , Adulto , Feminino , HumanosRESUMO
BACKGROUND: Parvovirus B19 (B19) infection is known to cause chronic infection leading to anemia in immunocompromised patients. Although nosocomial B19 infections in immunocompetent patients have been documented, no outbreaks in immunocompromised patients have been previously reported. Whether transmission can occur from a patient with chronic infection is also unknown. METHODS: An outbreak of B19 infection in a renal transplant unit was investigated by molecular analysis of the virus strains and a case-control study. RESULTS: Three patients had genetically identical virus strains suggesting the occurrence of nosocomial transmission. The index case transmitted infection many weeks after the onset of her clinical symptoms. Other patients at risk of acquiring infection were those most intensively immunosuppressed. Viral load in the serum correlated with the hematological response. A rebound in the viral load was associated with clinical relapse and the failure of i.v. immunoglobulin therapy. CONCLUSION: Nosocomial transmission of B19 can occur from immunocompromised patients even when they are in the chronic stage of the infection. The clinical and virological response to i.v. immunoglobulin therapy is variable and depends on the overall level of immunosuppression of the patient.
Assuntos
Infecção Hospitalar/transmissão , Transplante de Rim , Infecções por Parvoviridae/transmissão , Parvovirus B19 Humano , Adulto , Estudos de Casos e Controles , DNA Viral/sangue , Surtos de Doenças , Feminino , Unidades Hospitalares/organização & administração , Humanos , Pessoa de Meia-IdadeRESUMO
A retrospective study of the prevalence and pattern of tuberculosis in patients undergoing continuous ambulatory peritoneal dialysis (CAPD) was performed. Thirty-eight cases of tuberculosis were diagnosed among 790 patients (18 men, 20 women; mean age, 58 +/- 12.6 years) between July 1994 and June 2000. The interval between the initiation of CAPD and onset of tuberculosis ranged from 1 to 168 months (median, 22 months). There were 18 cases of pulmonary tuberculosis, 14 cases of tuberculous peritonitis, 5 cases of tuberculous lymphadenitis, and 1 case of tuberculous synovitis. Patients with pulmonary tuberculosis usually presented with fever, constitutional symptoms, and pleural effusion or pulmonary infiltrates on chest radiograph. Abdominal pain and turbid dialysate were the main presenting symptoms in patients with tuberculous peritonitis. Diagnosis was established by positive culture in 20 patients, typical histological characteristics on a tissue biopsy specimen in 10 patients, and response to empirical antituberculous treatment in 8 patients. The duration of symptoms before the diagnosis of tuberculosis and initiation of antituberculous treatment ranged from 7 to 57 days (median, 30 days). Antituberculous treatment consisted of isoniazid, rifampicin, pyrazinamide, and ofloxacin for 9 to 15 months. Antituberculous treatment generally was well tolerated. Twenty-seven patients (71%) completed antituberculous treatment. No recurrence of tuberculosis was observed after a mean follow-up of 19.8 months. Eleven patients (29%) died while on antituberculous treatment; none of the deaths appeared to be directly caused by tuberculosis. We conclude that: (1) tuberculosis is prevalent among CAPD patients in our locality; (2) extrapulmonary tuberculosis, particularly tuberculous peritonitis, is common; and (3) a high index of suspicion for tuberculosis among CAPD patients is warranted to ensure early diagnosis and prompt initiation of treatment.
Assuntos
Falência Renal Crônica/complicações , Mycobacterium tuberculosis/isolamento & purificação , Diálise Peritoneal Ambulatorial Contínua , Tuberculose/complicações , Idoso , Antituberculosos/uso terapêutico , Feminino , Hong Kong , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Peritonite Tuberculosa/complicações , Peritonite Tuberculosa/tratamento farmacológico , Peritonite Tuberculosa/mortalidade , Taxa de Sobrevida , Resultado do Tratamento , Tuberculose/tratamento farmacológico , Tuberculose/mortalidade , Tuberculose dos Linfonodos/complicações , Tuberculose dos Linfonodos/tratamento farmacológico , Tuberculose dos Linfonodos/mortalidade , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/mortalidadeRESUMO
The aim of the study was to compare the use of a novel differential culture medium CHROMagar, for both primary isolation and presumptive identificaton, with the method currently used in our laboratory for screening mid-stream-urine samples (MSU). Routine methods (RM) included blotting paper imprinting of all specimens and additional quantitative culture on cysteine lactose electrolyte-deficient agar (CLED) for selected samples together with Microbact 12E for further identification. The CHROMagar method (CH) relied on the use of blotting paper imprints, colonial colour and morphology on CHROMagar only. With respect to the 3390 MSU specimens examined, both methods yielded similar results in 3240, including > or = 87% of Escherichia coli, Pseudomonas spp., Staphylococcus spp., Proteus mirabilis/Morganella morganii and Enterobacter/Serratia/Klebsiella/Citrobacter spp. Of the 52 discordant identifications, yeasts were reported as staphylococci on CHROMagar in 10. The overall cost of materials per specimen was US$ 0.30 by RM and $ 0.24 by CH. It took about 3 min to perform each Microbact test. Thus, CHROMagar plus Gram stain and other simple bench tests gave results similar to those using our current method, but had the advantage of saving time and materials.
Assuntos
Técnicas Bacteriológicas/instrumentação , Meios de Cultura , Urina/microbiologia , Técnicas Bacteriológicas/economia , Meios de Cultura/economia , HumanosRESUMO
The immunosuppressive drug mycophenolate mofetil (MMF) acts by releasing mycophenolic acid (MPA), which inhibits the enzyme inosine monophosphate dehydrogenase (IMPDH) and thus inhibits de novo purine synthesis. Unlike cyclosporine (CsA), MMF has no direct effect on cytokine gene expression in vitro. We examined the effect of MMF, in comparison to CsA, on in vivo production of interferon-gamma (IFN-gamma) in mice. Two stimuli for IFN-gamma induction were used: (1) allogeneic P815 mastocytoma ascites tumour cells and (2) bacterial lipopolysaccharide (LPS). The allogeneic response is dependent on clonal expansion of T cells, while the LPS response is polyclonal and T cell independent. Since major histocompatibility complex (MHC) induction in mouse kidney is IFN-gamma dependent, we assessed the in vivo induction of IFN-gamma indirectly by measuring MHC induction in mouse kidneys in three systems: radiolabelled antibody binding assay, immunoperoxidase staining in tissue sections, and Northern blotting for steady-state MHC mRNA levels. IFN-gamma steady-state mRNA levels were assessed by reverse transcriptase polymerase chain reaction (RT-PCR). In the allogeneic response, MMF (40-160 mg/kg/day) reduced the production of IFN-gamma in a dose-dependent fashion. MHC class I and II induction was reduced by 35% to 74% and 30% to 74%, respectively. However, MMF had less effect on the induction of MHC by a nonimmune stimulus, bacterial LPS, whereas CsA reduced the induction of IFN-gamma in both responses. We conclude that MMF reduces the IFN-dependent induction of MHC in vivo during specific immune responses, probably by limiting clonal expansion, while preserving nonspecific cytokine production in response to LPS.
Assuntos
Rejeição de Enxerto/imunologia , Antígenos de Histocompatibilidade Classe II/biossíntese , Antígenos de Histocompatibilidade Classe I/biossíntese , Imunossupressores/administração & dosagem , Interferon gama/biossíntese , Ácido Micofenólico/análogos & derivados , Imunologia de Transplantes/imunologia , Animais , Ciclosporina/farmacologia , Feminino , Antígenos de Histocompatibilidade Classe I/genética , Antígenos de Histocompatibilidade Classe II/genética , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos CBA , Ácido Micofenólico/administração & dosagem , Transplante de Neoplasias , Transplante HomólogoRESUMO
Considerable evidence has shown a correlation between fiber size and degree of necrosis in dystrophic muscles of hamster, X-linked muscular dystrophy (MDX) mice and humans. It has been proposed that small-caliber fibers have an immunity to the phenotypic expression of the dystrophic gene(s). The results from the present study show a discordance between fiber size and necrosis in dystrophic muscles of C57BL/6J dy2J/dy2J mice. Extensor carpi radialis longus and brevis muscles (ECRL and ECRB respectively) were compared in normal and dystrophic 2-week, 4-week and 12-month animals by measuring the mean cross-sectional area of type II fibers, determination of relative proportions of types IIA and IIB fibers and calculation of percentage of fibers exhibiting centronucleation in an entire cross-section of muscle (stained for haematoxylin and eosin or ATPase). The ECRL and ECRB muscles were found to have identical sizes of fiber at each of the 3 ages studied and similar proportions of fiber types, yet the former muscle developed and retained significantly more necrosis (manifest as centronucleation) than the latter.
Assuntos
Regulação da Expressão Gênica , Músculos/patologia , Distrofia Muscular Animal/patologia , Fenótipo , Fatores Etários , Animais , Camundongos , Camundongos Endogâmicos C57BL , Distrofia Muscular Animal/genética , Distrofia Muscular Animal/metabolismo , NecroseRESUMO
We report on two patients who developed rapidly progressive demyelinating neuropathy within 6 to 10 weeks after the initiation of continuous ambulatory peritoneal dialysis. The neuropathy in one patient resolved after kidney transplantation while that of the other patient improved with immunosuppressive therapy. The close temporal relationship between the initiation of peritoneal dialysis and the onset of neuropathy suggests that these two events may be causally related.
Assuntos
Doenças Desmielinizantes/etiologia , Nefropatias/etiologia , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Adulto , Doenças Desmielinizantes/terapia , Progressão da Doença , Humanos , Imunossupressores/uso terapêutico , Nefropatias/terapia , Transplante de Rim , MasculinoRESUMO
The socioeconomic statuses of Asian countries are diverse, and government reimbursement policies for renal replacement programs vary greatly from one country to another. Both factors affect not only the availability of treatment, but also the choice of dialysis modality. A close correlation is demonstrated between the dialysis treatment rate for end-stage renal disease (ESRD) and the gross domestic product (GDP) per capita income. A biphasic relationship with the GDP per capita income and the peritoneal dialysis (PD) utilization rate is observed, in that the countries with the highest and lowest treatment rates tend to have lower PD utilization rates, whereas countries with modest treatment rates tend to have higher PD utilization rates. In contrast, countries with high continuous ambulatory peritoneal dialysis (CAPD) utilization rates have the lowest automated peritoneal dialysis (APD) utilization rates. The low APD utilization rates are due to fact that, in most instances, patients themselves must purchase the APD machine, and the machines are relatively more expensive in Asian Pacific countries. Continuous cycling peritoneal dialysis (CCPD) is most frequently practiced. Generally, convenience for employment is the main indication for the utilization of APD. Other important indications are the convenience of treatment in young or elderly uremic patients. Contrary to the practice in CAPD treatment, detailed documentation of dialysis adequacy and nutritional status is not routinely done in patients undergoing APD treatment in most Asian Pacific countries. In conclusion, APD is an underdeveloped treatment modality in the renal replacement programs of Asian Pacific countries. The low utilization of APD is clearly influenced by non medical factors including government reimbursement policy and the cost of PD machines.
Assuntos
Diálise Peritoneal/estatística & dados numéricos , Ásia Oriental , Humanos , Renda , Diálise Peritoneal/economia , Diálise Peritoneal Ambulatorial Contínua/estatística & dados numéricos , Fatores SocioeconômicosRESUMO
OBJECTIVE: We undertook to study the attitudes toward dialysis of patients approaching end-stage renal failure and to analyze those attitudes from a cultural perspective. SETTING: The study was performed in the pre-dialysis clinic of a tertiary referral renal center. PATIENTS: All patients of Chinese ethnic origin seen in the pre-dialysis clinic from 1995 to 2000 for assessment of dialysis therapy were included. METHOD: We performed a retrospective analysis of patient records with regard to attitudes of the patients toward dialysis, reasons for those attitudes, and factors that could lead to a subsequent change in attitude. RESULTS: We assessed 462 patients over the 6-year period. Their mean age was 65.5 +/- 13.3 years, and 43.9% of the patients had diabetes. Peritoneal dialysis (PD) was offered to 74% of the patients, and hemodialysis (HD) to 3.9%. Among the patients offered PD, only 44% accepted dialysis. After counselling, 54% of the patients who originally declined PD ultimately accepted it. The major reasons for refusing PD were the ideas of "having lived long enough" and "lack of family support." Most other reasons could be overcome by counselling. Only a minority of patients demanded hemodialysis. CONCLUSIONS: Declining an offer of dialysis was common. Counselling helped patients to accept PD. Certain cultural elements that hindered acceptance of dialysis were involved in the ideas of "having lived long enough" and "lack of family support." Those cultural elements should be tackled more specifically during counselling.
Assuntos
Atitude Frente a Saúde , Falência Renal Crônica/terapia , Aceitação pelo Paciente de Cuidados de Saúde , Diálise Peritoneal/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , China/etnologia , Cultura , Feminino , Hong Kong , Humanos , Falência Renal Crônica/psicologia , Masculino , Pessoa de Meia-Idade , Características de Residência , Estudos Retrospectivos , Recusa do Paciente ao TratamentoRESUMO
The clinical outcome of long-term renal allograft recipients in the Chinese population has not been reported previously. We analysed patients from the pre-cyclosporin era who had grafts that functioned for > 10 years. Forty-five patients (31 men, 14 women; mean age 30, follow-up duration 13.3 years), representing a 10-year graft survival of 53%, were included. Thirty-six patients (80%) received living-related allografts and 9 (20%) received cadaveric or living-unrelated renal transplantation. The mean serum creatinine at last follow-up was 1.36 mg/dl (range, 0.83-4.08). Major posttransplantation complications included: hypertension in 25 (56%), infection in 16 (36%), acute rejection in 15 (33%), lipid disorder in 13 (29%), liver disease in 7 (16%), osteonecrosis in 5 (11%), malignancy in 4 (9%), coronary artery disease in 3 (7%), and diabetes mellitus in 3 (7%). Five grafts were lost: 3 to chronic rejection, and 2 to patients with stable function who died of non-renal causes. Proteinuria correlated strongly with graft function and survival, and marginally with hypertension. In hepatitis B carriers, serum alpha-feto protein is useful in the early detection of hepatocellular carcinoma. We conclude that while patients in the pre-cyclosporin era can survive with excellent graft function beyond the first decade, the risk of complications leading to significant morbidity still remains even when patients are receiving minimal doses of immunosuppression in the second decade.
Assuntos
Ciclosporinas , Imunossupressores , Falência Renal Crônica/cirurgia , Transplante de Rim/efeitos adversos , Transplante de Rim/mortalidade , Imunologia de Transplantes , Adolescente , Adulto , Distribuição por Idade , China , Estudos de Avaliação como Assunto , Feminino , Seguimentos , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Transplante de Rim/imunologia , Masculino , Pessoa de Meia-Idade , Gravidez , Estudos Retrospectivos , Fatores de Risco , Distribuição por Sexo , Taxa de Sobrevida , Fatores de Tempo , Transplante Homólogo/imunologia , Transplante Homólogo/mortalidade , Resultado do TratamentoRESUMO
Exit-site infection (ESI) refractory to medical therapy is an important complication of continuous ambulatory peritoneal dialysis (CAPD). Between July 1994 and June 1998, 28 patients in our hospital underwent simultaneous removal and reinsertion of Tenckhoff catheters for the treatment of refractory ESI. The ESI was caused by Pseudomonas aeruginosa in 22 patients (78%), methicillin-resistant Staphylococcus aureus in 5 patients (18%), and diphtheroid bacilli in 1 patient (4%). The patients had received antibiotic treatment for a mean duration of 11.6 +/- 5.8 weeks (range: 3-28 weeks) before their operations. During each operation, the old Tenckhoff catheter was removed and a new catheter was inserted in the opposite side of the abdomen. CAPD was resumed after two weeks of intermittent peritoneal dialysis. All patients received intravenous antibiotic cover for seven days after the operation. Early post-operative complications were uncommon. At one year after the operation, 22 patients (78%) were free of ESI. Six patients (22%) had a recurrence of ESI 21.3 +/- 6 weeks (range: 16-32 weeks) after their operation. All new infections were treated successfully with antibiotics. Seven patients (25%) had one episode of peritonitis each, all of which resolved with intraperitoneal antibiotic treatment. We conclude that simultaneous removal and reinsertion of Tenckhoff catheters is a safe and effective method for the treatment of refractory ESI. The procedure alleviates the need for temporary hemodialysis and allows an early return to CAPD.
Assuntos
Infecções Bacterianas/etiologia , Infecções Bacterianas/terapia , Cateteres de Demora/efeitos adversos , Diálise Peritoneal Ambulatorial Contínua , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos RetrospectivosRESUMO
Peritoneal dialysis catheter (PDC) is the lifeline of peritoneal dialysis (PD) patients. One of the critical issues for successful PD is a well-functioning PDC which is timely inserted. It is the implantation technique rather than the catheter design that determines the outcome of the catheter. Dedication in acquiring the appropriate technique is vital to the success of a PD program. In this paper, we discuss the pros and cons of various techniques used for PDC implantation. A detailed description of PDC implantation by using the minilaparotomy method is presented. We strongly recommend mini-laparotomy as the method of choice for PDC implantation by nephrologists.
RESUMO
Increasing prevalence of methicillin-resistant Staphylococcus aureus (MRSA) worldwide with limited therapeutic options is a growing public health concern. Natural products have been shown to possess antibacterial actions against MRSA. Flavonoids from natural products have been shown to possess antibacterial actions against MRSA by antagonizing its resistance mechanisms. Diosmin and diosmetin are natural flavonoids found in a variety of citrus fruits. The aim of this study was to investigate whether diosmin and diosmetin could inhibit the growth of MRSA and the in vitro enzymatic activity of a newly discovered MRSA drug target, pyruvate kinase (PK). By using a panel of MRSA strains with known resistant mechanisms, neither diosmin nor diosmetin was shown to possess direct antibacterial activities against all tested MRSA strains. However, in checkerboard assay, we found that diosmetin together with erythromycin, could synergistically inhibit the growth of ABC-pump overexpressed MRSA-RN4220/pUL5054, and time kill assay also showed that the antibacterial activities of diosmetin with erythromycin were bactericidal. Diosmetin was further shown to significantly suppress the MRSA PK activities in a dose dependent manner. In conclusion, the inhibition of MRSA PK by diosmetin could lead to a deficiency of ATP and affect the bacterial efflux pump which might contribute to the antibacterial actions of diosmetin against MRSA.
Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Antibacterianos/farmacologia , Eritromicina/farmacologia , Flavonoides/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Piruvato Quinase/antagonistas & inibidores , Trifosfato de Adenosina/metabolismo , Diosmina/farmacologia , Relação Dose-Resposta a Droga , Sinergismo Farmacológico , Staphylococcus aureus Resistente à Meticilina/metabolismo , Testes de Sensibilidade MicrobianaAssuntos
Anti-Infecciosos Locais/uso terapêutico , Clorexidina/análogos & derivados , Nitrato de Prata/uso terapêutico , Infecção dos Ferimentos/tratamento farmacológico , Unidades de Queimados , Clorexidina/uso terapêutico , Farmacorresistência Bacteriana , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , PrevalênciaRESUMO
ETHNOPHARMACOLOGICAL RELEVANCE: Baicalein, the active constituent derived from Scutellaria baicalensis Georgi., has previously been shown to significantly restore the effectiveness of ß-lactam antibiotics and tetracycline against methicillin-resistant Staphylococcus aureus (MRSA). With multiple therapeutic benefits, the antibacterial actions of baicalein may also be involved in overcoming other bacterial resistance mechanisms. The aim of the present study was to further investigate antibacterial activities of baicalein in association with various antibiotics against selected Staphylococcus aureus strains with known specific drug resistance mechanisms. MATERIAL AND METHODS: A panel of clinical MRSA strains was used for further confirmation of the antibacterial activities of baicalein. The effect of baicalein on inhibiting the enzymatic activity of a newly discovered MRSA-specific pyruvate kinase (PK), which is essential for Staphylococcus aureus growth and survival was also examined. RESULTS: In the checkerboard dilution test and time-kill assay, baicalein at 16 µg/ml could synergistically restore the antibacterial actions of ciprofloxacin against the NorA efflux pump overexpressed SA-1199B, but not with the poor NorA substrate, pefloxacin. Moreover, synergistic effects were observed when baicalein was combined with ciprofloxacin against 12 out of 20 clinical ciprofloxacin resistant strains. For MRSA PK studies, baicalein alone could inhibit the enzymatic activity of MRSA PK in a dose-dependent manner. CONCLUSION: Our results demonstrated that baicalein could significantly reverse the ciprofloxacin resistance of MRSA possibly by inhibiting the NorA efflux pump in vitro. The inhibition of MRSA PK by baicalein could lead to a deficiency of ATP which might further contribute to the antibacterial actions of baicalein against MRSA.