Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A considerable effort has been spent in the past three decades to investigate various aspects of liposomes as novel drug delivery systems. In 1990, the first amphotericin B (AmB) liposomal preparation (L-AmB) under the brand name AmBisome was introduced into the market by Vestar. The successful marketing of the product moved liposomes out of the stage of experimental obscurity to the realistic stage of clinical utility. The launch of AmBisome sparked off the introduction of other lipid-based AmB products marketed by Liposome Technology (Amphocil) and The Liposome Co. (Abelcet). The drive behind the development of a modified formulation of AmB was to improve the therapeutic index of this drug with respect to its major drawback associated with both acute and chronic toxic effects. In a 30-year-long experience with AmB, several reports were recorded in the literature of acute adverse effects, such as fever, rigors, vomiting, cardiotoxicity and hypotension occurring during infusion; while long-term therapy was reported to be associated with hypokalemia, renal dysfunction and hematological abnormalities. Another serious problem encountered with the drug had been the poor response obtained in immunocompromised patients like those with AIDS, neutropenia and cancer patients on chemotherapy. The encapsulation of amphotericin B in liposomal vesicles was hence targeted not only to obtain an improvement in the therapeutic index but also to see if it was useful in eradicating deep-seated fungal infections in immunocompromised patients. The liposomal AmB was found to have a better therapeutic index and lower toxicity than the commercial AmB preparations. The LD50 of AmBisome in mouse was 175 mg/kg compared with 3.7 mg/kg for Fungizone, the commercial preparation of AmB. Additionally, L-AmB has prolonged circulation time, and extravasates into the site of infection and delivers the drug directly to the site, with no nephrotoxicity and neurotoxicity as experienced with AmB. This review traces the course of development of L-AmB and discusses the rationale behind the development of its liposomal preparation. The results in in vitro, in vivo and clinical studies, mechanism of action, biodistribution, and formulation considerations of L-AmB are described. The clinical experience with the marketed preparation is reviewed.
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PMID:Development of liposomal amphotericin B formulation. 953 20

Aspergillosis is an infrequent but commonly fatal infection among HIV-infected individuals. We review 342 cases of pulmonary Aspergillus infection that have been reported among HIV-infected patients, with a focus on invasive disease. Invasive pulmonary aspergillosis usually occurs among patients with <50 CD4 cells/mm3. Major predisposing conditions include neutropenia and steroid treatment. Fever, cough, and dyspnea are each present in >60% of the cases. BAL is often suggestive, but biopsy specimens are necessary for definite diagnosis. Amphotericin B is the mainstay of treatment and mortality is > 80%. Avoiding neutropenia and judicious use of steroids may be helpful in prevention. Aggressive diagnostic approach, early initiation of treatment, adequate dosing of antifungals, and close follow-up may improve the currently dismal prognosis.
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PMID:Pulmonary aspergillosis and invasive disease in AIDS: review of 342 cases. 967 77

It has been suggested that a better outcome of neutropenia-associated invasive fungal infections can be achieved when high doses of lipid formulations of amphotericin B are used. We now report a randomized multicentre study comparing liposomal amphotericin B (AmBisome, 5 mg/kg/d) to amphotericin B deoxycholate (AmB, 1 mg/kg/d) in the treatment of these infections. Of 106 possible patients, 66 were enrolled and analysed for efficacy: nine had documented fungaemia, 17 had other invasive mould infections and 40 had suspected pulmonary aspergillosis. After completion of the course medication, in the AmBisome group (n = 32) 14 patients had achieved complete response, seven a partial response and 11 were failures as compared to 6, 13 and 15 patients (n = 34) treated with AmB (P=0.09); P=0.03 for complete responders. A favourable trend for AmBisome was found at day 14, in patients with documented infections and in patients with pulmonary aspergillosis (P=0.05 and P=0.096 respectively). Mortality rates were lower in patients treated with AmBisome (adjusted for malignancy status, P=0.03). More patients on AmB had a >100% increase of their baseline serum creatinine (P<0.001). The results indicate that, in neutropenic patients with documented or suspected invasive fungal infections AmBisome 5 mg/kg/d was superior to AmB 1 mg/kg/d with respect to efficacy and safety.
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PMID:Liposomal amphotericin B compared with amphotericin B deoxycholate in the treatment of documented and suspected neutropenia-associated invasive fungal infections. 1005 Jul 32

Twelve cases of Trichosporon spp. fungemias occurring in a national cancer institution within 10 years are described. The trend of hematogenous trichosporonosis within the last 10 years is increasing. While no cases occurred in 1988-1991, after 1991, Trichosporon spp. was the most common species among non-Candida spp. fungemias in 1993-1997. The 12 cases of fungemia included 5 that started while the patients were receiving prophylaxis with oral itraconazole, and 2 appeared despite empiric therapy with amphotericin B. Five of the 12 fungemias were catheter associated. Risk factors for fungemia were: central venous catheter, broad-spectrum antibiotics (third-generation cephalosporins plus aminoglycoside); all but 1 had neutropenia and were receiving antineoplastic chemotherapy. All but 2 of the patients died of systemic fungal infection (83.3% mortality). Amphotericin B was administered to all but 1 patient, who was not treated because he died the day after his culture was found to be positive for T. beigelii, before antifungals were administered. All cases infected with T. pullulans were catheter related, and all these patients died. One of the remaining 9 fungemias was caused by T. capitatum (Blastoschizomyces capitatus), and 8 by T. beigelii. Only 2 patients were cured, 1 with a combination therapy with amphotericin B plus fluconazole, and 1 with amphotericin B monotherapy. Several risk factors (neutropenia, acute leukemia, prior therapy or prophylaxis with antifungals and catheter as source of fungemia, breakthrough fungemia) were significantly associated with Trichosporon spp. fungemia, in comparison to 63 C. albicans candidemia occurring in the same period at the same institution. Attributable mortality of hematogenous trichosporonosis was also significantly higher (83.3% vs. 15.8%, P<0.001) than that of hematogenous candidiasis.
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PMID:Hematogenous trichosporonosis in cancer patients: report of 12 cases including 5 during prophylaxis with itraconazol. 992 73

The effect of an extensive prophylactic antimicrobial regimen was prospectively assessed in 126 patients after high-dose chemotherapy and autologous PBSC. They received ciprofloxacin (500 mg/12 h), acyclovir (200 mg/6 h), and itraconazole (200 mg/12 h) orally until neutrophil recovery. Febrile patients received i.v. imipenem (500 mg/6 h) to which vancomycin and amikacin were added if fever persisted for 2-3 and 5 days, respectively. Amphotericin B lipid complex was further given on day 7 or 8 of fever. Median times for a neutrophil count of >0.5 x 10(9)/l and a platelet count of >20 x 10(9)/l were 9 and 11 days. Severe neutropenia (<0.1 x 10(9)/l) lasted for a median of 5 days in which 72% of febrile episodes and 50% of cases of bacteremia occurred. Gram-positive bacteria were isolated in 30 of 40 episodes of bacteremia, 25 of which were caused by Staphylococcus epidermidis. Clinical foci were the intravascular catheter in 35 cases, respiratory infection in 11, cellulitis in two, anal abscess in one, and neutropenic enterocolitis in one. The high incidence of febrile episodes (94%) and bacteremias (31%) may be due to the lack of efficacy of antimicrobial prophylaxis and the persistence of a 5-day period of severe neutropenia.
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PMID:Infectious complications in 126 patients treated with high-dose chemotherapy and autologous peripheral blood stem cell transplantation. 1003 47

We studied the safety of low-dose amphotericin B lipid complex (ABLC, at 1 mg/kg/day) in 30 persistently febrile (>38 degrees C for at least 5 days or with recurrent fever after 3 days of apyrexia) and neutropenic (<0.5 x 10(9)/l) adult patients with hematologic malignancies. The median age was 45 years (range 18-67), most (60%) had an acute leukemia and all had fever of unknown origin (FUO). The total duration of neutropenia was a median of 17 days (range 9-33), and the total number of days with fever 10 days (range 6-39). Seven patients experienced mild-to- moderate infusion-related adverse events (IRAE). The serum creatinine and urea increased from baseline to end of therapy in 76 and 63% of cases, but the maximum levels reached were <130 micromol/l and <11 mmol/l, respectively, in all cases. Liver enzymes showed modest but significant increases in most patients during therapy, while bilirubin decreased in 74% of cases. Response to treatment (defervescence within 6 days without developing a fungal or nonfungal infection) was seen in 22 cases (73%, 95% CI 58-89%), while 8 episodes were considered treatment failures: 2 due to persistent FUO, 1 withdrew due to IRAE, 2 developed nonfungal infections and 3 developed a presumed or definite invasive mycosis. We conclude that low-dose ABLC is very safe and well tolerated and seems as effective as c-AmB for this indication. Thus, randomized trials at this dose level appear justified to demonstrate any real benefit over c-AmB or other lipid formulations for the treatment of FUO in neutropenic patients.
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PMID:Low-dose amphotericin B lipid complex for the treatment of persistent fever of unknown origin in patients with hematologic malignancies and prolonged neutropenia. 1022 43

Infectious complications after renal transplantation remain a major cause of morbidity and mortality. Mucormycosis is a rare infection in renal transplant recipients; however, mortality is exceedingly high. Risk factors predisposing to this disease include prolonged neutropenia, diabetes, and patients who are immunosuppressed (Singh N, Gayowski T, Singh J, Yu LV. Invasive gastrointestinal zygomycosis in a liver transplant recipient: case report and review of zygomycosis in solid-organ transplant recipients, Clin Infect Dis 1995: 20: 617). Life-threatening infections can occur, as this fungus has the propensity to invade blood vessel endothelium, resulting in hematological dissemination. We report a case of cavitary Rhizopus lung infection, 2 months after renal transplantation, where the patient was treated successfully with Amphotericin B and surgical resection of the lesions with preservation of his allograft function. In this era of intensified immunosuppression, we may see an increased incidence of mucormycosis in transplant population. Invasive diagnostic work-up is mandatory in case of suspicion; Amphotericin B and, in selected cases, surgical resection are the mainstays of therapy.
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PMID:Pulmonary Rhizopus infection in a diabetic renal transplant recipient. 1069 28

Systemic fungal infections are a major problem in bone marrow transplant recipients who have prolonged neutropenia or who receive high-dose corticosteroids. Prophylaxis with Fluconazole or low-dose amphotericin B reduces, but does not eliminate these infections. To determine which prophylactic agent is better, we performed a prospective randomized study. Patients undergoing allogeneic (related or unrelated) or autologous marrow or peripheral stem cell transplantation were randomized to receive Fluconazole (400 mg/day p. o. or i.v.) or amphotericin B (0.2 mg/kg/day i.v.) beginning 1 day prior to stem cell transplantation and continuing until recovery of neutrophils to >500/microl. Patients were removed from their study drug for drug-associated toxicity, invasive fungal infection or suspected fungal infection (defined as the presence of fever >38 degrees C without positive culture while on broad-spectrum anti-bacterial antibiotics). Proven or suspected fungal infections were treated with high-dose amphotericin B (0.5-0.7 mg/kg/day). Patients were randomized at each institution and stratified for the type of transplant. The primary end-point of the study was prevention of documented fungal infection; secondary endpoints included fungal colonization, drug toxicity, duration of hospitalization, duration of fever, duration of neutropenia, duration and total dose of high-dose amphotericin B and overall survival to hospital discharge. From July 1992 to October 1994, a total of 355 patients entered into the trial with 159 patients randomized to amphotericin B and 196 to Fluconazole. Patient groups were comparable for diagnosis, age, sex, prior antibiotic or antifungal therapy, use of corticosteroids prior to transplantation and total duration of neutropenia. Amphotericin B was significantly more toxic than Fluconazole especially in related allogeneic transplantation where 19% of patients developed toxicity vs 0% of Fluconazole recipients (p < 0.05). Approximately 44% of all patients were removed from prophylaxis for presumed fungal infection. Proven fungal infections occurred in 4.1% and 7.5% of Fluconazole and amphotericin-treated patients, respectively. Proven fungal infections occurred in 9.1% and 14.3% of related allogeneic marrow recipients receiving Fluconazole or amphotericin B, respectively, and 2.1% and 5.6% of autologous marrow recipients receiving Fluconazole or amphotericin B, respectively (P > 0.05). In this prospective trial, low-dose amphotericin B prophylaxis was as effective as Fluconazole prophylaxis, but Fluconazole was significantly better tolerated.
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PMID:Fluconazole vs low-dose amphotericin B for the prevention of fungal infections in patients undergoing bone marrow transplantation: a study of the North American Marrow Transplant Group. 1080 6

Patients with haematological malignancies form one of the most susceptible host groups for microbial infection, especially during neutropenia. The incidence of invasive fungal infections has increased in recent years, highlighting the need for better diagnosis and more effective antifungal therapies. Amphotericin B is the drug of choice for many fungal infections, although toxicity and the need for intravenous infusion restrict its use. When possible, oral administration of antifungal agents is preferable but intravenous administration is often needed and current oral agents have their limitations: fluconazole because of a narrow spectrum of activity; itraconazole capsules because of erratic absorption. In this review, prophylactic and treatment options for systemic fungal infections are discussed. The specific needs of patients with different types of leukaemia and the benefits of new amphotericin B and itraconazole formulations are examined.
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PMID:Prophylaxis and treatment of fungal infections associated with haematological malignancies. 1092 37

Fungal infections are life-threatening complications in patients with prolonged neutropenia. Amphotericin B, which is fungicidal and has a broad spectrum of antifungal activity, remains the current gold standard agent. However, because of its low therapeutic index, new lipid formulations of amphotericin B have been developed with better tolerance and less toxicity. The use of 5-fluorocytosine is waning because of the medullar toxicity of this agent. Fluconazole and itraconazole are both fungistatic and are more convenient for the treatment of fungal infections in haemodynamically stable patients.
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PMID:Standard antifungal therapy in neutropenic patients. 1105 97


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