地塞米松影响念珠菌对抗真菌药物敏感性的实验研究

目的 探讨地塞米松在体外试验中是否影响念珠菌对抗真菌药物的敏感性,以了解糖皮质激素与抗真菌药物直接作用于念珠菌时是否存在相互作用。方法 用微量液体培养基稀释法分别测定26株白念珠菌与地塞米松（0．2mg／ml）共同孵育前、孵育24～48h及7d时氟康唑、伊曲康唑、两性霉素B的最低抑菌浓度（MIC）值,并作对照。结果 白念珠菌与地塞米松孵育24～48h后、孵育后第7d氟康唑和伊曲康唑的MIC值升高,分别与孵育前的MIC值存在统计学差异,但孵育24～48h后的MIC与孵育后第7d的MIC无统计学差异;白念珠菌与地塞米松共同孵育24～48h后两性霉素B的MIC值也较孵育前升高,但第7d的MIC值与孵育前无差异。结论 地塞米松可增加三种抗真菌药物对于白念珠菌的MIC,但三种抗真菌药物间存在差异,表明地塞米松对于氟康唑和伊曲康唑体外抗白念珠菌的活性有拮抗作用,但没有时间依赖性,地塞米松对于两性霉素B的影响较氟康唑和伊曲康唑小,且影响时间较短。     

伊曲康唑序贯疗法治疗老年MODS患者侵袭性肺部真菌感染14例

目的 观察伊曲康唑序贯疗法治疗老年多脏器功能障碍综合征（MODS）患者侵袭性肺部真菌感染的疗效。方法 回顾分析重症监护病房（ICU）中,老年MODS患者侵袭性真菌感染14例,最初应用伊曲康唑注射液7～14d,第1～2d,200mg,1次／12h,第3～14d,200mg,1次／d;然后,采用伊曲康唑胶囊或口服液序贯治疗,400mg／d剂量水平,疗程2—4周。结果 临床有效率85．7％,真菌清除率为92．9％,真菌清除平均天数为6．1d;患者28d生存率85．7％,不良反应发生率为42．9％。结论 对老年MODS合并侵袭性真菌感染患者在综合治疗的基础上,应用广谱抗真菌药物——伊曲康唑序贯疗法,是巩固疗效,防止复发值得推广的给药方式。临床应用伊曲康唑时,应注意适应证、药物不良反应及药物的相互作用。     

热带念珠菌引起唇部念珠菌性肉芽肿1例

报告1例由热带念珠菌引起的唇部感染。患者女,22岁,下唇部斑块1 a。皮损组织病理学检查及真菌培养见热带念珠菌生长。给予伊曲康唑200 mg/d口服等治疗1个月后皮损完全消失。     

重症监护病房真菌谱及耐药性6年变化趋势

目的 调查我院重症监护室（ICU）近6 a临床分离真菌株的菌种结构及耐药性变化.方法 2007 ～2012年从我院1435例ICU患者中分离出的1 435株真菌均为首次分离的菌株.采用Cox-Stuart趋势检验回顾性分析了分离真菌株的菌种结构和主要真菌对常用抗真菌药物耐药率的变化趋势.结果 2007 ～2012年间,我院tCU真菌检出阳性标本总数从159株/a逐年增加至396株/a.其中,白念珠菌、近平滑念珠菌、曲霉的构成比波动范围分别为34.6％ ～ 50.3％、6.3％～9.6％、1.3％～3.2％,2010 ～2012年较2007 ～2009年构成比总体均有上升趋势,P=0.02.热带念珠菌、光滑念珠菌、克柔念珠菌构成比波动范围分别为13.6％ ～ 17.3％、9.4％ ～ 22.6％、1.4％ ～5.2％,P=0.18,构成比均无明显上升或下降趋势.2010 ～2012年较2007 ～2009年,白念珠菌对氟康唑和伊曲康唑耐药率的变化均呈降低趋势,P=0.02.热带念珠菌对氟康唑和伊曲康唑耐药率的变化均呈降低趋势,P =0.02;光滑念珠菌对伊曲康唑耐药率的变化总体呈上升趋势,P =0.02.结论 我院ICU近6 a来白念珠菌仍然为临床最常见的真菌分离株,白念珠菌、近平滑念珠菌及曲霉占总真菌分离株的百分比有上升趋势.白念珠菌及热带念珠菌对氟康唑和伊曲康唑耐药率均呈降低趋势,光滑念珠菌对伊曲康唑耐药率呈上升趋势.     

伊曲康唑联合复方黄松洗液治疗念珠菌性龟头炎临床观察

目的观察伊曲康唑联合复方黄松洗液治疗念珠菌性龟头炎的疗效。方法采用随机对照法观察90例患者。随机平均分为3组,观察伊曲康唑联合复方黄松洗液组(联合组)、伊曲康唑组及复方黄松洗液组治疗念珠菌性龟头炎临床疗效。根据临床症状、体征及真菌清除率判定疗效。结果治疗后2周,联合组、伊曲康唑组临床疗效明显优于复方黄松洗液组,差异有显著性(P0.01、P0.05);联合组临床疗效略高于伊曲康唑组,差异无显著性(P0.05)。三组真菌清除率,联合组和伊曲康唑组明显高于复方黄松洗液组(P0.05)。复发率三组无显著差异(P0.05)。前两组出现4例轻度不良反应。结论复方黄松洗液联合伊曲康唑治疗念珠菌性包皮龟头炎临床效果好,且经济、安全,但与单用伊曲康唑组无显著差异性。提示伊曲康唑联合复方黄松洗液治疗念珠菌性包皮龟头炎的疗效主要源于伊曲康唑。     

生殖器念珠菌病家庭内感染的临床研究

目的了解引起夫妻双方生殖器念珠菌病的病原菌是否为同一种致病菌,并行药物敏感性检测,以指导临床治疗。方法采用常规念珠菌培养方法培养,API20CAUX进行鉴定,微量稀释法行药敏检测。结果88例患者（44对夫妻）中,检出白念珠菌73例。夫妻双方共同由同一菌种致病例数为41对,白念珠菌引起者为36对,光滑念珠菌引起者为2对,近平滑2对,克柔念珠菌1对。与对照组相比,差异有统计学意义。体外药敏显示88株念珠菌对制霉菌素全部敏感,对克霉唑也高度敏感,对伊曲康唑、氟康唑有不同程度的耐药。结论夫妻一方患有生殖器念珠菌病时,另一方应做好性伴通知工作,行相应检查,必要时行药敏实验,以降低念珠菌病的复发率。     

伊曲康唑治疗严重烧伤患者真菌感染的疗效分析

目的 评价伊曲康唑治疗严重烧伤患者真菌感染的疗效及其安全性。方法 采用开放、随机研究单组评估设计,治疗前2d：伊曲康唑注射液2次／d,间隔12h,200mg／次。此后1次／d,剂量200mg,间隔24h,1疗程14d。试验结束后口服伊曲康唑口服液维持治疗至少4周,2次／d,200mg／次。结果 伊曲康唑治疗23例严重烧伤患者总有效率为60．87％;本组86．96％的患者临床疗效为改善;63．64％的患者真菌学疗效为真菌清除;8．70％和52．17％的患者综合疗效分别为痊愈和显效,未发生不良反应。结论 伊曲康唑治疗严重烧伤患者真菌感染有良好的疗效、不良反应少。     

不同剂量伊曲康唑口服联合外用抗真菌药物治疗足癣的疗效观察

目的比较伊曲康唑200mg／d与400ne／d口服联合外用复方酮康唑乳膏治疗足癣的疗效。方法36例非角化型足癣患者随机分为2组,分别采用不同剂量伊曲康唑口服联合外用复方酮康唑乳膏治疗1周,比较停药2周时两组患者的治疗有效率和真菌清除率。结果200mg组治疗有效率为83．3％（15／18）,痊愈率为55．6％（10／18）,真菌清除率为66．7％（12／18）;400mg组治疗有效率为88．9％（16／18）,痊愈率为55．6％（10／18）,真菌清除率为77．8％（14／18）;统计学分析两组之间差异无显著性。结论伊曲康唑200mg／d口服即可有效治疗非角化型足癣,增加伊曲康唑口服剂量至400mg/d并不能提高治疗效果。     

1例多器官损伤继发茄病镰刀菌血症的真菌学研究

目的 对车祸致多器官损伤继发茄病镰刀菌血症的真菌学研究.方法 以我院收治的l例多器官损伤的患者为研究对象,采集患者深静脉血液进行血培养,对培养出的真菌进一步行表型分析、分子鉴定,并行E-test真菌药敏实验.结果 血液标本细菌培养阴性,但真菌培养3次呈现丝状真菌生长,对菌丝的表型和分子鉴定检测结果均提示为“茄病镰刀菌”.E-test真菌药敏实验结果提示该菌株对两性霉素（AMB）和伏立康唑（VOZ）敏感,对伊曲康唑（ITZ）、卡泊芬净（CS）和氟康唑（FCZ）耐药.结论 镰刀菌可引起人体局限性或播散性感染,对多种抗真菌药物呈现耐药,常危及生命.因此对车祸后经清创、抗感染等治疗后仍发热者,有必要做血液真菌培养.菌株的鉴定可采用表型分析、分子鉴定.     

五环三萜类柴胡皂苷单体对白念珠菌伊曲康唑耐药株活性研究

目的 从柴胡中提取具有抗真菌活性的五环三萜类单体Bp3,研究该单体对伊曲康唑耐药白念珠菌菌株的作用及其与伊曲康唑的相互作用.方法 参照CLSI标准,采用棋盘微量稀释法,测定单用Bp3、伊曲康唑及两者联合使用时对20株伊曲康唑耐药白念珠菌菌株的MIC,计算部分抑菌浓度指数(FIC),判定两药相互作用.结果 单独用药时Bp3及伊曲康唑对伊曲康唑耐药白念珠菌菌株MIC的几何均数值(GM值)分别为1.941 μg/mL和1.008 μg/mL.联合用药时Bp3和伊曲康唑的GM值分别降低为1.189 μg/mL和0.346 μg/mL.2种药物单用和联合使用时MIC值差异均有统计学意义(P＜0.05),联用时在20株耐药株均表现为协同或相加作用.结论 五环三萜类单体Bp3对白念珠菌伊曲康唑耐药株有一定的抑制作用,且与伊曲康唑有协同或相加作用.     

Direct comparison of the pharmacodynamics of four antifungal drugs in a mouse model of disseminated candidiasis using microbiological assays of serum drug concentrations

The aim of this study was to compare the pharmacodynamics of the azole antifungal drugs fluconazole, itraconazole and ketoconazole, and the polyene antifungal amphotericin B, in a mouse model of disseminated Candida albicans infection. In order to directly compare effective serum concentrations of these antifungals, drug concentrations were assayed microbiologically by measuring inhibition of C. albicans mycelial growth (mMIC) in a mouse serum-based assay (serum antifungal titer). Efficacy in the mouse infection model was determined using an organ-based (kidney burden) endpoint. For all four drugs, the serum antifungal titers, 8 hr after administration of single doses of drugs at a range of drug concentrations, correlated closely with C. albicans kidney fungal burden in the mouse model. The results showed that determining serum antifungal titer may be used to accurately represent kidney fungal burden in a mouse model of disseminated candidiasis and allowed direct comparison of the pharmacodynamics of differing classes of antifungal drugs.     

Effects of microbial challenge on sleep in rabbits

Rabbits challenged with viable Staphylococcus aureus exhibit marked time-dependent changes in sleep patterns. To examine the generality of this observation, we monitored sleep patterns for 24 h before and for 48 h after intravenous inoculation of rabbits with Streptococcus pyogenes, Escherichia coli, or Candida albicans. All three agents produced complex time-dependent changes in sleep. Inoculation with S. pyogenes or C. albicans increased the time spent in slow-wave sleep (SWS) during h 4-20 after challenge. Electroencephalographic delta wave amplitudes (DWA) increased during h 4-8 after injection, but decreased during h 24-38 after inoculation. Altered sleep patterns were not observed when similar doses of heat-killed organisms were administered. In contrast, inoculation with E. coli produced a large increase in both SWS time and DWA for the first 2-4 h after inoculation. DWA then decreased from 6 to 32 h after inoculation. Similar effects occurred when heat-killed E. coli were administered. Rapid eye movement sleep was reduced by all three agents. These data demonstrate that altered sleep patterns occur in response to infectious challenge in rabbits, and that these changes are related to the type of infectious organism involved.     

Active and passive immunization with rHyr1p-N protects mice against hematogenously disseminated candidiasis

We previously reported that Candida albicans cell surface protein Hyr1 encodes a phagocyte killing resistance factor and active vaccination with a recombinant N-terminus of Hyr1 protein (rHyr1p-N), significantly protects immunocompetent mice from disseminated candidiasis. Here we report the marked efficacy of rHyr1p-N vaccine on improving the survival and reducing the fungal burden of disseminated candidiasis in both immunocompetent and immunocompromised mice using the FDA-approved adjuvant, alum. Importantly, we also show that pooled rabbit anti-Hyr1p polyclonal antibodies raised against 8 different peptide regions of rHyr1p-N protected mice in a hematogenously disseminated candidiasis model, raising the possibility of developing a successful passive immunotherapy strategy to treat this disease. Our data suggest that the rabbit anti-Hyr1p antibodies directly neutralized the Hyr1p virulence function, rather than enhanced opsonophagocytosis for subsequent killing by neutrophil in vitro. Finally, the rHyr1p-N vaccine was protective against non-albicans Candida spp. These preclinical data demonstrate that rHyr1p-N is likely to be a novel target for developing both active and passive immunization strategies against Candida infections.     

The 'bull's eye' pattern in hepatic tomography

Invasive fungal infections are more commonly found in patients who develop neutropenia after chemotherapy. A 4-year-old girl with diagnosis of acute lymphoid leukemia developed febrile neutropenia after chemotherapy. Broad spectrum antibiotics and antimycotic therapy were initiated. Candida albicans was isolated and Entamoeba histolytica was observed in stool examination. Chronic disseminated candidiasis had developed and was treated with amphotericin B, initially, and fluconazol. Computed tomography images were obtained that demonstrated a classic 'bull's eye' pattern; a concurrent histological study confirmed the diagnosis. Candida spp. is the major cause of opportunistic mycosis in immunosuppresed patients receiving chemotherapy for haematologic malignancies. An initial infection results in disseminated candidiasis, which persists and becomes chronic. In the 4-year-old patient, the identified risk factors consisted of a previous therapy with broad spectrum antibiotics, the gastrointestinal tract colonization with Candida albicans and prolonged neutropenia. Imaging diagnoses are made by ultrasonography, computed tomography and magnetic resonance. With ultrasound and tomography, 4 distinct patterns have been described. Pattern 1 ('wheels within wheels') and 2 ('bull's eye') are important, since they are characteristic of chronic disseminated candidiasis. The third pattern (hypoechoic image) is the most common finding with both techniques. In the current patient, patterns 2 and 3 were seen and the diagnosis was confirmed by histological study.     

Modulation of neutrophil function in host defense against disseminated Candida albicans infection in mice

Neutrophils (PMNs) constitute the main mechanism of host defense against acute invasive and disseminated candidiasis. Recent studies have demonstrated that tumor necrosis factor-alpha (TNFalpha), interleukin-6 (IL-6) and granulocyte colony-stimulating factor (G-CSF) play an important role in the recruitment of PMNs at the site of invasive Candida infection. In the absence of either TNFalpha or IL-6, the course of experimental disseminated candidiasis is more severe, due to defective PMN recruitment. Treatment of mice with recombinant G-CSF (rG-CSF) leads to a significantly reduced mortality during disseminated candidiasis. The outgrowth of Candida albicans from the organs of rG-CSF-treated mice is significantly decreased. Treatment with the combination of rG-CSF and fluconazole has an additive effect on the reduction of fungal load in the organs. In subacute or chronic disseminated Candida infection, rG-CSF is less effective, indicating that neutrophil recruitment and activation are crucial in acute, life-threatening candidiasis, whereas other host defense mechanisms control the outcome of less overwhelming invasive Candida infection.     

A D-octapeptide drug efflux pump inhibitor acts synergistically with azoles in a murine oral candidiasis infection model

Clinical management of patients undergoing treatment of oropharyngeal candidiasis with azole antifungals can be impaired by azole resistance. High-level azole resistance is often caused by the overexpression of Candida albicans efflux pump Cdr1p. Inhibition of this pump therefore represents a target for combination therapies that reverse azole resistance. We assessed the therapeutic potential of the D-octapeptide derivative RC21v3, a Cdr1p inhibitor, in the treatment of murine oral candidiasis caused by either the azole-resistant C. albicans clinical isolate MML611 or its azole-susceptible parental strain MML610. RC21v3, fluconazole (FLC), or a combination of both drugs were administered orally to immunosuppressed ICR mice at 3, 24, and 27 h after oral inoculation with C. albicans. FLC protected the mice inoculated with MML610 from oral candidiasis, but was only partially effective in MML611-infected mice. The co-application of RC21v3 (0.02 μmol per dose) potentiated the therapeutic performance of FLC for mice infected with either strain. It caused a statistically significant decrease in C. albicans cfu isolated from the oral cavity of the infected mice and reduced oral lesions. RC21v3 also enhanced the therapeutic activity of itraconazole against MML611 infection. These results indicate that RC21v3 in combination with azoles has potential as a therapy against azole-resistant oral candidiasis.     

Disseminated candidiasis and hepatic malarial infection in mannose-binding-lectin-A-deficient mice

To examine the physiological functions of mannose-binding lectin A (MBL-A), we generated mice that were deficient in MBL-A and examined their susceptibilities to the microbial pathogens Candida albicans and Plasmodium yoelii, an accepted experimental malaria model in mouse. We found no differences in the survival rates and fungal burdens of wild-type and MBL-A(-/-) mice with disseminated C. albicans infection. The two mouse strains were also similar in their abilities to resist hepatic accumulation of P. yoelii parasites. We conclude that MBL-A deficiency does not alter resistance to disseminated candidiasis or initial hepatic invasion by P. yoelii.     

CO(2) acts as a signalling molecule in populations of the fungal pathogen Candida albicans

When colonising host-niches or non-animated medical devices, individual cells of the fungal pathogen Candida albicans expand into significant biomasses. Here we show that within such biomasses, fungal metabolically generated CO(2) acts as a communication molecule promoting the switch from yeast to filamentous growth essential for C. albicans pathology. We find that CO(2)-mediated intra-colony signalling involves the adenylyl cyclase protein (Cyr1p), a multi-sensor recently found to coordinate fungal responses to serum and bacterial peptidoglycan. We further identify Lys 1373 as essential for CO(2)/bicarbonate regulation of Cyr1p. Disruption of the CO(2)/bicarbonate receptor-site interferes selectively with C. albicans filamentation within fungal biomasses. Comparisons between the Drosophila melanogaster infection model and the mouse model of disseminated candidiasis, suggest that metabolic CO(2) sensing may be important for initial colonisation and epithelial invasion. Our results reveal the existence of a gaseous Candida signalling pathway and its molecular mechanism and provide insights into an evolutionary conserved CO(2)-signalling system.     

A murine model of esophageal candidiasis with local characteristic symptoms

A simple method to establish a murine esophageal candidiasis model that displayed characteristic symptoms of the condition was developed using the sedative agent, chlorpromazine. Mice were immunosuppressed with prednisolone and were given tetracycline hydrochloride. One day later, the mice received chlorpromazine to keep them in a sedated state for about 3 hr. Under the sedated condition, they were infected with 4 x 10(7) viable cells of Candida albicans by intra-esophageal injection with a round-head needle on syringe. From day 3 to day 6 post inoculation, 10(5)-10(6) colony forming units of C. albicans were recovered from the esophageal tube of each mouse and whitish, curd-like patches were observed on most of the inner surface of the tube. Histological examination showed that C. albicans in esophageal lesions grew mainly in mycelial form. In this experimental model, intragastric administration of an itraconazole oral solution (20 mg/kg/day) was clearly effective. This model would provide a useful tool to investigate the pathogenesis of C. albicans esophageal infection and the efficacy of various antifungal agents microbiologically and symptomatically.     

Antifungal type 1 responses are upregulated in IL-10-deficient mice

C57BL/6 mice are highly resistant to infections caused by Candida albicans and Aspergillus fumigatus. To elucidate the role of IL-10 produced by C57BL/6 mice during these infections, parameters of infection and immunity to it were evaluated in IL-10-deficient and wild-type mice with disseminated or gastrointestinal candidiasis or invasive pulmonary aspergillosis. Unlike parasitic protozoan infection, C. albicans or A. fumigatus infection did not induce significant acute toxicity in IL-10-deficient mice, who, instead, showed reduced fungal burden and fungal-associated inflammatory responses. The increased resistance to infections as compared to wild-type mice was associated with upregulation of innate and acquired antifungal Th1 responses, such as a dramatically higher production of IL-12, nitric oxide (NO) and TNF-alpha as well as IFN-gamma by CD4+ T cells. Pharmacological inhibition of NO production greatly reduced resistance to gastrointestinal candidiasis, thus pointing to the importance of IL-10-dependent NO regulation at mucosal sites in fungal infections. These results are reminiscent of those obtained in genetically susceptible mice, in which IL-10 administration increased, and IL-10 neutralization decreased, susceptibility to C. albicans and A. fumigatus infections. Collectively, these observations indicate that the absence of IL-10 augments innate and acquired antifungal immunity by upregulating type 1 cytokine responses. The resulting protective Th1 responses lead to a prompt reduction of fungal growth, thus preventing tissue destruction and lethal levels of proinflammatory cytokines.