FV is primarily produced in the liver, and congenital FV deficiency is a disorder with an incidence of one in 1 million. Standard care is to treat severe bleeding phenotypes with FFP as there is no recombinant or plasma‐derived FV concentrate. We present a case of a neonate with known severe FV deficiency diagnosed after prolonged bleeding after circumcision who represented at age 2 months with a large left intraparenchymal hemorrhage. His bleed was treated with FFP, platelet transfusion, recombinant VIIa, and emergent evacuation. He was maintained on plasma infusions but was unable to space his infusions beyond 48 hours. Liver transplantation was considered as a definitive treatment for this condition. While awaiting a suitable liver, his FV trough levels occasionally dropped below 5%, and he suffered from a second acute intracranial bleed. He received an orthotopic liver transplant at age 5 months, resulting in correction of his FV levels. He has not required any plasma infusions post‐transplantation and has had no further bleeding episodes. Liver transplantation should be considered as definitive treatment early in the course for patients with severe FV deficiency and first time life‐threatening bleed.

Transfusion practices for bone marrow harvests: a survey analysis from the AABB Bone Marrow Quality Improvement Initiative Working Group

BACKGROUNDSilent cerebral infarcts are the most common neurologic injury in children with sickle cell anemia and are associated with the recurrence of an infarct (stroke or silent cerebral infarct). We tested the hypothesis that the incidence of the recurrence of an infarct would be lower among children who underwent regular blood transfusion therapy than among those who received standard care.METHODSIn this randomized, single-blind clinical trial, we randomly assigned children with sickle cell anemia to receive regular blood transfusions (transfusion group) or standard care (observation group). Participants were between 5 and 15 years of age, with no history of stroke and with one or more silent cerebral infarcts on magnetic resonance imaging and a neurologic examination showing no abnormalities corresponding to these lesions. The primary end point was the recurrence of an infarct, defined as a stroke or a new or enlarged silent cerebral infarct.RESULTSA total of 196 children (mean age, 10 years) were randomly assigned to the observation or transfusion group and were followed for a median of 3 years. In the transfusion group, 6 of 99 children (6%) had an end-point event (1 had a stroke, and 5 had new or enlarged silent cerebral infarcts). In the observation group, 14 of 97 children (14%) had an end-point event (7 had strokes, and 7 had new or enlarged silent cerebral infarcts). The incidence of the primary end point in the transfusion and observation groups was 2.0 and 4.8 events, respectively, per 100 years at risk, corresponding to an incidence rate ratio of 0.41 (95% confidence interval, 0.12 to 0.99; P = 0.04).CONCLUSIONSRegular blood-transfusion therapy significantly reduced the incidence of the recurrence of cerebral infarct in children with sickle cell anemia. (Funded by the National Institute of Neurological Disorders and Stroke and others; Silent Cerebral Infarct Multi-Center Clinical Trial ClinicalTrials.gov number, NCT00072761, and Current Controlled Trials number, ISRCTN52713285.)

PURPOSE:To characterize relationships between specific immune cell subsets in bone marrow (BM) or granulocyte colony-stimulating factor-mobilized peripheral blood (PB) stem cells collected from unrelated donors and clinical outcomes of patients undergoing transplantation in BMTCTN 0201.PATIENTS AND METHODS:Fresh aliquots of 161 BM and 147 PB stem-cell allografts from North American donors randomly assigned to donate BM or PB stem cells and numbers of transplanted cells were correlated with overall survival (OS), relapse, and graft-versus-host disease (GvHD).RESULTS:Patients with evaluable grafts were similar to all BMTCTN 0201 patients. The numbers of plasmacytoid dendritic cells (pDCs) and naïve T cells (Tns) in BM allografts were independently associated with OS in multivariable analyses including recipient and donor characteristics, such as human leukocyte antigen mismatch, age, and use of antithymocyte globulin. BM recipients of > median number of pDCs, naïve CD8(+) T cells (CD8Tns), or naïve CD4(+) T cells (CD4Tns) had better 3-year OS (pDCs, 56% v 35%; P = .025; CD8Tns, 56% v 37%; P = .012; CD4Tns, 55% v 37%; P = .009). Transplantation of more BM Tns was associated with less grade 3 to 4 acute GvHD but similar rates of relapse. Transplantation of more BM pDCs was associated with fewer deaths resulting from GvHD or from graft rejection. Analysis of PB grafts did not identify a donor cell subset significantly associated with OS, relapse, or GvHD.CONCLUSION:Donor immune cells in BM but not PB stem-cell grafts were associated with survival after unrelated-donor allogeneic hematopoietic stem-cell transplantation. The biologic activity of donor immune cells in allogeneic transplantation varied between graft sources. Donor grafts with more BM-derived Tns and pDCs favorably regulated post-transplantation immunity in allogeneic hematopoietic stem-cell transplantation.

The most common form of neurologic injury in sickle cell anemia (SCA) is silent cerebral infarction (SCI). In the Silent Cerebral Infarct Multi-Center Clinical Trial, we sought to identify risk factors associated with SCI. In this cross-sectional study, we evaluated the clinical history and baseline laboratory values and performed magnetic resonance imaging of the brain in participants with SCA (HbSS or HbSβ° thalassemia) between the ages of 5 and 15 years with no history of overt stroke or seizures. Neuroradiology and neurology committees adjudicated the presence of SCI. SCIs were diagnosed in 30.8% (251 of 814) participants who completed all evaluations and had valid data on all prespecified demographic and clinical covariates. The mean age of the participants was 9.1 years, with 413 males (50.7%). In a multivariable logistic regression analysis, lower baseline hemoglobin concentration (P < .001), higher baseline systolic blood pressure (P = .018), and male sex (P = .030) were statistically significantly associated with an increased risk of an SCI. Hemoglobin concentration and systolic blood pressure are risk factors for SCI in children with SCA and may be therapeutic targets for decreasing the risk of SCI. This study is registered at www.clinicaltrials.gov as #NCT00072761.

is silent cerebral infarction (SCI). In the Silent Cerebral Infarct Multi-Center Clinical Trial, sought to identify risk factors we evaluated the baseline laboratory and performed magnetic resonance of the brain with (HbSS thalassemia) no of Neuroradiology

Abstract Abstract 1004 Data from single institutional clinical studies have indicated that the content of CD34+ cells, T-cells, and dendritic cells in a bone marrow allograft are associated with clinical outcomes. The relationship between the cellular constituents of hematopoietic allografts and clinical outcomes was prospectively studied in BMT CTN 0201 in which patients with hematological malignancies (and their donors) were randomized to transplantation with bone marrow or G-CSF-mobilized peripheral blood stem cell (PB) allografts. A secondary objective of this study was to correlate graft characteristics with overall survival (OS). 551 patients were enrolled at 50 North American centers between January 2004 and September 2009 in a BMT CTN-sponsored randomized clinical trial supported by the NHLBI and NCI. Of the 278 subjects randomized to BM, aliquots from 173 BM allografts collected in North America were analyzed at a central laboratory for the content of CD34+ progenitors and immune cell subsets by flow cytometry, and of 151 of these BM transplants had complete clinical data and are the subject of this analysis. The subset of 151 patients were similar to the total group of patients transplanted in BMT CTN 0201, with a median age of 38, and 42% of patients with AML, 26% with ALL, 10% CML, and 21% MDS. 74% of patients had low risk disease, and 47% received 12 Gy TBI and cyclophosphamide with the remainder receiving myeloablative busulfan-based (48%) or fludarabine/melphalan conditioning (5%). GvHD prophylaxis was predominately a calcineurin inhibitor plus methotrexate (91%). 26.5% of patients received grafts from HLA mismatched donors. Clinical outcomes, including OS, acute GVHD III–IV and chronic GVHD, were similar between the subset of patients with analysis of BM cells and the 127 BM recipients without product analysis. 46 progenitor and immune cell subsets were selected for study based upon the absence of a strong correlation with another graft subset (Pearson or Spearman correlation >0.8) and a priori interest or the number of evaluable patients. Graft characteristics were then described separately for survivors and those who died and compared using a nonparametric Mann-Whitney Wilcoxon test. P-values were not adjusted for multiple comparisons, but only covariates for which the q value is <0.2 are presented. The median number of nucleated cells, CD34+ cells, and total T-cells in the allograft were 256, 2.7, and 23 × 10E6/kg, respectively. The numbers of these donor cells, and the numbers of B-cells, NK cells, and activated T-cells in the BM graft, were not significantly associated with OS. Two of the cell subsets in the BM graft were identified as being significantly associated with transplant outcomes with univariate p-values <0.01 and q values of <0.2: pre-plasmacytoid dendritic cells (pDC) (median number 0.3 × 10E6/kg; p=0.007), and naive CD8+ T-cells (CD8N; median number of 1.3 × 10E6/kg; p=0.009). Stratifying the entire group of transplant recipients by median values for either pre-pDC or CD8N showed better overall survival among patients receiving larger numbers of each donor cell subset (Figure 1). Estimated 3 year OS for patients receiving > 0.3 × 10E6 pre-pDC/kg was 56% versus 35% for recipients of <0.3 × 10E6 pre-pDC/kg (p=0.025, HR for high versus low of 0.58, 95% CI 0.37–0.93) and with 56% estimated 3 year OS for patients receiving > 1.3 × 10E6 CD8N/kg versus 37% for recipients of <1.3 × 10E6 CD8N/kg (p=0.012, HR for high versus low of 0.52, 95% CI 0.32–0.87). Transplantation with more than the median number of CD8N was also associated with a significantly decreased risk of grade III–IV acute GvHD 0.34 (0.12–0.96), p=0.041, but with a higher cumulative incidence of cGVHD at 2 years: 0.55 vs. 0.26, p=0.004. Relapse rates were similar among recipients of larger versus lower numbers of donor pre-pDC and CD8N.Figure 1.Overall survival for recipients of allogeneic BM grafts stratified by the median numbers of Left: donor naive CD8+ T-cells (> or ≤ 1.3 × 10E6/kg) or Right: donor pDC precursors (> or ≤ 0.3 × 10E6/kg) in the BM graft.Figure 1. Overall survival for recipients of allogeneic BM grafts stratified by the median numbers of Left: donor naive CD8+ T-cells (> or ≤ 1.3 × 10E6/kg) or Right: donor pDC precursors (> or ≤ 0.3 × 10E6/kg) in the BM graft. Among patients receiving unrelated donor bone marrow grafts, higher numbers of donor cell that have important activity in regulating post-transplant immunity, including an unexpected role for CD8N in reducing severe acute GvHD, are associated with improved clinical outcomes. Disclosures: No relevant conflicts of interest to declare.

ABSTRACT Anidulafungin is an echinocandin with activity against Candida species and Aspergillus species. Adult dosages under study are 50 mg/day for esophageal candidiasis and 100 mg/day for invasive candidiasis and aspergillosis. Little is known, however, about the safety and pharmacokinetics of anidulafungin in children. A multicenter, ascending-dosage study of neutropenic pediatric patients was therefore conducted. Patients were divided into two age cohorts (2 to 11 years and 12 to 17 years) and were enrolled into sequential groups to receive 0.75 or 1.5 mg/kg of body weight/day. Blood samples were obtained following the first and fifth doses. Anidulafungin was assayed in plasma, and pharmacokinetic parameters were determined. Safety was assessed using National Cancer Institute (NCI) common toxicity criteria. Pharmacokinetic parameters were determined for 12 patients at each dosage (0.75 mg/kg/day or 1.5 mg/kg/day). Concentrations and drug exposures were similar for patients between age cohorts, and weight-adjusted clearance was consistent across age. No drug-related serious adverse events were observed. One patient had fever (NCI toxicity grade of 3), and one patient had facial erythema, which resolved with slowing the infusion rate. Anidulafungin in pediatric patients was well tolerated and can be dosed based on body weight. Pediatric patients receiving 0.75 mg/kg/day or 1.5 mg/kg/day have anidulafungin concentration profiles similar to those of adult patients receiving 50 or 100 mg/day, respectively.

The members of the genus Aspergillus are opportunistic fungi that cause disease almost exclusively in patients with chronic lung pathology or depressed immune defenses. Aspergillus disease has a variety of clinical manifestations, ranging from allergic responses occurring in the absence of fungal growth or airway colonization to invasion and destruction of lung parenchyma with or without dissemination to other organs (Denning and Stevens, 1990; Greenberger, 2002; Marr et al., 2002; Muller et al., 2002). Over the past decades, the incidence of invasive aspergillosis has increased dramatically as a result of an expansion of the population of immunocompromised patients. At particular risk for invasive aspergillosis are those patients with persistent and profound neutropenia as a result of aggressive anticancer chemotherapy, hematopoietic stem cell transplant, or aplastic anemia (Gerson et al., 1984; Weinberger et al., 1992; Walsh et al., 1994; Perea and Patterson, 2002). In addition, congenital or acquired qualitative defects of the phagocytic cells have also been associated with the development of invasive aspergillosis: examples are patients with chronic granulomatous disease, Job syndrome, or those receiving prolonged courses of immunosuppressive agents such as corticosteroids. Aspergillosis is uncommon in patients with AIDS but when present it is associated with short survival after diagnosis (Shetty et al., 1997; Holding et al., 2000).

Zygomycosis, an uncommon but frequently fatal mycosis caused by fungi of the class Zygomycetes, develops most commonly as an opportunistic disease. Successful therapy involves a combined approach based on early diagnosis, prompt institution of medical therapy, and extensive surgical debridement of all devitalized tissue. Given the rarity of this condition, novel therapeutic strategies have been limited and only tested on an individual basis. The use of high-dose lipid formulations of amphotericin B, prompt reversal of the underlying predisposing condition, and hyperbaric oxygen are the most common strategies that have shown potential value in the treatment of zygomycosis.

The in vivo and ex vivo effects of macrophage colony-stimulating factor (M-CSF) were studied in a profoundly neutropenic rabbit model in order to determine its potential to augment pulmonary host defence against Aspergillus. M-CSF (100-600 microg/kg/d) was administered prophylactically to neutropenic rabbits with pulmonary aspergillosis starting three days pre-inoculation and then throughout neutropenia. Rabbits receiving M-CSF had significantly increased survival (P=0.01) and decreased pulmonary injury, as measured by decreased pulmonary infarction (P=0.004), when compared with untreated controls. Microscopic studies demonstrated greater numbers of activated pulmonary alveolar macrophages (PAMs) in lung tissue of rabbits receiving M-CSF, in comparison to controls (P<0.001). PAMs harvested from rabbits treated with M-CSF had a significantly greater percent phagocytosis of Aspergillus fumigatus conidia than did PAMs from controls (P=0.04). These data indicate that prophylactic administration of M-CSF augments pulmonary host defence against A. fumigatus and suggest a potential role for this cytokine as adjunctive therapy in the treatment of pulmonary aspergillosis in the setting of profound neutropenia.

Oropharyngeal candidiasis (OPC) is a common opportunistic infection in human immunodeficiency virus (HIV)-infected patients and other immunocompromised hosts. Clotrimazole troches are widely used in the treatment of mucosal candidiasis. However, little is known about the potential contribution of clotrimazole resistance to the development of refractory mucosal candidiasis. We therefore investigated the potential emergence of resistance to clotrimazole in a prospectively monitored HIV-infected pediatric population receiving this azole. Adapting the National Committee for Clinical Laboratory Standards M27-A reference method for broth antifungal susceptibility testing of yeasts to clotrimazole, we compared MICs in macrodilution and microdilution assays. We further analyzed the correlation between these in vitro findings and the clinical response to antifungal therapy. One isolate from each of 87 HIV-infected children was studied by the macrodilution and microdilution methods. Two inoculum sizes were tested by the macrodilution method (10(3) and 10(4) CFU/ml) in order to assess the effect of inoculum size on clotrimazole MICs. The same isolates also were tested using a noncolorimetric microdilution method. Clotrimazole concentrations ranged from 0.03 to 16 microg/ml. Readings were performed after incubation for 24 and 48 h at 35 degrees C. For 62 (71.2%) of 87 clinical isolates, the MICs were low (< or =0.06 microg/ml). The MIC for 90% of the strains tested was 0.5 microg/ml, and the highest MIC was 8 microg/ml. There was no significant difference between MICs at the two inoculum sizes. There was 89% agreement (+/-1 tube) between the microdilution method at 24 h and the macrodilution method at 48 h. If the MIC of clotrimazole for an isolate of C. albicans was > or =0.5 microg/ml, there was a significant risk (P < 0.001) of cross-resistance to other azoles: fluconazole, > or = 8 microg/ml (relative risk [RR] = 8.9); itraconazole, > or =1 microg/ml (RR = 10). Resistance to clotrimazole was highly associated with clinically overt failure of antifungal azole therapy. Six (40%) of 15 patients for whom the clotrimazole MIC was > or =0.5 microg/ml required amphotericin B for refractory mucosal candidiasis versus 4 (5.5%) of 72 for whom the MIC was <0.5 microg/ml (P = 0.001; 95% confidence interval = 2.3 to 22; RR = 7.2). These findings suggest that an interpretive breakpoint of 0.5 microg/ml may be useful in defining clotrimazole resistance in C. albicans. The clinical laboratory's ability to determine MICs of clotrimazole may help to distinguish microbiologic resistance from the other causes of refractory OPC, possibly reducing the usage of systemic antifungal agents. We conclude that resistance to clotrimazole develops in isolates of C. albicans from HIV-infected children, that cross-resistance to other azoles may develop concomitantly, and that this resistance correlates with refractory mucosal candidiasis.

Annals of the New York Academy of SciencesVolume 918, Issue 1 p. 362-366 Impact of Chemotherapy for AIDS-Related Malignancies in Pediatric HIV Disease CORINA E. GONZALEZ, Corresponding Author CORINA E. GONZALEZ HIV/AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA Address for correspondence: Corina E. Gonzalez, M.D., Children's National Medical Center, Pediatric Medicine, Suite 3.5-600, 111 Michigan Ave., N.W., Washington, DC 20010. cgonzalez@cnmc.orgSearch for more papers by this authorMELISSA ADDE, MELISSA ADDE Pediatric Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USASearch for more papers by this authorPERDITA TAYLOR, PERDITA TAYLOR HIV/AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USASearch for more papers by this authorLAUREN V. WOOD, Corresponding Author LAUREN V. WOOD HIV/AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA Address for correspondence: Corina E. Gonzalez, M.D., Children's National Medical Center, Pediatric Medicine, Suite 3.5-600, 111 Michigan Ave., N.W., Washington, DC 20010. cgonzalez@cnmc.orgSearch for more papers by this authorIAN MAGRATH, IAN MAGRATH Pediatric Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USASearch for more papers by this author CORINA E. GONZALEZ, Corresponding Author CORINA E. GONZALEZ HIV/AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA Address for correspondence: Corina E. Gonzalez, M.D., Children's National Medical Center, Pediatric Medicine, Suite 3.5-600, 111 Michigan Ave., N.W., Washington, DC 20010. cgonzalez@cnmc.orgSearch for more papers by this authorMELISSA ADDE, MELISSA ADDE Pediatric Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USASearch for more papers by this authorPERDITA TAYLOR, PERDITA TAYLOR HIV/AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USASearch for more papers by this authorLAUREN V. WOOD, Corresponding Author LAUREN V. WOOD HIV/AIDS Malignancy Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA Address for correspondence: Corina E. Gonzalez, M.D., Children's National Medical Center, Pediatric Medicine, Suite 3.5-600, 111 Michigan Ave., N.W., Washington, DC 20010. cgonzalez@cnmc.orgSearch for more papers by this authorIAN MAGRATH, IAN MAGRATH Pediatric Oncology Branch, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USASearch for more papers by this author First published: 25 January 2006 https://doi.org/10.1111/j.1749-6632.2000.tb05507.xCitations: 4Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume918, Issue1PREVENTION AND TREATMENT OF HIV INFECTION IN INFANTS AND CHILDRENNovember 2000Pages 362-366 RelatedInformation

Lymphoid interstitial pneumonitis (LIP), as well as other conditions characterized by abnormal lymphoid proliferation, has been described with increased frequency in patients with HIV infection. Lymphoid interstitial pneumonitis is particularly common in pediatric AIDS and has been reported in up to 40% of vertically infected infants and children with pulmonary disease.1–4 Although it is known that LIP can cause significant morbidity, the natural history and pathogenesis of this condition are not well understood. Recent advances in the understanding of the pathogenesis of interstitial lung disease suggest that it may be a cytokine-mediated process, the initiation and perpetuation of which is dependent on immune responses to HIV antigens and direct effects of HIV and/or other pathogens such as EpsteinBarr virus (EBV).5,6 The natural history of pediatric HIV infection is that of a progressive disease leading to profound immunosuppression with continuous viral replication.7,8 This process entails changes in the host immunity that can definitely affect the course of lymphoid proliferations. Similarly, antiretroviral therapy, particularly highly active antiretroviral therapy (HAART), can also affect the course of these conditions. Because HIV-infected patients survive longer as a result of improved antiretroviral therapy and supportive care, long-term studies on the course of LIP and other lymphoid interstitial disorders (LPDs) are now possible.

BACKGROUND:Little is known about the epidemiology and clinical features of esophageal candidiasis (EC) in pediatric AIDS. We therefore investigated the clinical presentation and risk factors of EC in a large prospectively monitored population of HIV-infected children at the National Cancer Institute. PATIENTS AND METHODS:We reviewed the records of all HIV-infected children (N = 448) followed between 1987 and 1995 for a history of esophageal candidiasis to characterize the epidemiology, clinical features, therapeutic interventions and outcome of esophageal candidiasis. To understand further the risk factors for EC in pediatric AIDS, we then performed a matched case-control analysis of 25 patients for whom control cases were available. RESULTS:There were 51 episodes of EC documented in 36 patients with 23 male and 13 female patients (0.2 to 17 years; median CD4, count 11/microl), representing a frequency of EC of 8.0%. Concurrent oropharyngeal candidiasis (OPC) was the most common clinical presentation of EC (94%); other signs and symptoms included odynophagia (80%), retrosternal pain (57%), fever (29%), nausea/vomiting (24%), drooling (12%), dehydration (12%), hoarseness (6%) and upper gastrointestinal bleeding (6%). The causative organism documented in 36 episodes (18 from OPC, 17 from endoscopic biopsy and 1 from autopsy) was Candida albicans in all cases. Patients received treatment for EC with amphotericin B (63%), fluconazole (29%), ketoconazole (4%) or itraconazole (1%). A clinical response was documented in all 45 evaluable episodes. In 6 other cases, EC was a final event without contributing to the cause of death. By a conditional logistic regression model for matched data, the best predictor of EC was the presence of prior OPC (P<0.0001), followed by CD4 count and CD4 percentage (P = 0.0002) and use of antibacterial antibiotics (P = 0.0013). The risks associated with low CD4 count were independent of that of prior OPC. CONCLUSION:EC in pediatric AIDS is a debilitating infection, which develops in the setting of prior OPC, low CD4 counts and previous antibiotics.

ABSTRACT Oropharyngeal and esophageal candidiasis (OPEC) is a frequent opportunistic mycosis in immunocompromised patients. Azole-resistant OPEC is a refractory form of this infection occurring particularly in human immunodeficiency virus (HIV)-infected patients. The procedures developed by the Antifungal Subcommittee of the National Committee for Clinical Laboratory Standards (NCCLS) are an important advance in standardization of in vitro antifungal susceptibility methodology. In order to further understand the relationship between NCCLS methodology and antifungal therapeutic response, we studied the potential correlation between in vitro susceptibility to fluconazole and in vivo response in a rabbit model of fluconazole-resistant OPEC. MICs of fluconazole were determined by NCCLS methods. Three fluconazole-susceptible (FS) (MIC, ≤0.125 μg/ml) and three fluconazole-resistant (FR) (MIC, ≥64 μg/ml) isolates of Candida albicans from prospectively monitored HIV-infected children with OPEC were studied. FR isolates were recovered from children with severe OPEC refractory to fluconazole, and FS isolates were recovered from those with mucosal candidiasis responsive to fluconazole. Fluconazole at 2 mg/kg of body weight/day was administered to infected animals for 7 days. The concentrations of fluconazole in plasma were maintained above the MICs for FS isolates throughout the dosing interval. Fluconazole concentrations in the esophagus were greater than or equal to those in plasma. Rabbits infected with FS isolates and treated with fluconazole had significant reductions in oral mucosal quantitative cultures (P < 0.001) and tissue burden of C. albicans in tongue, soft palate, and esophagus (P < 0.001). In comparison, rabbits infected with FR isolates were unresponsive to fluconazole and had no reduction in oral mucosal quantitative cultures or tissue burden of C. albicans versus untreated controls. We conclude that there is a strong correlation between in vitro fluconazole susceptibility by NCCLS methods and in vivo response to fluconazole therapy of OPEC due to C. albicans.

The effects of the hematoregulatory peptide SK&F 107647 were examined in a persistently and profoundly neutropenic rabbit model of disseminated candidiasis in order to determine its potential to enhance resistance against infection and its role as an adjunct to conventional antifungal chemotherapy. In healthy animals, SK&F 107647 elicited a time-dependent increase in CD11b-positive monocytes and neutrophils, When administered to neutropenic rabbits infected with Candida albicans, no significant differences in the number of CFU per gram in any of the tissues tested compared with the number in untreated control rabbits were detected. However, when SK&F 107647 was administered in combination with low doses of amphotericin B, there was a significant reduction in organism burden in the lungs, liver, spleen, and kidneys compared with the burdens in the organs of untreated control animals and in the lungs and kidneys compared with the burdens in the lungs and kidneys of animals treated with amphotericin B alone. These data suggest a potential role for this peptide as adjunctive therapy in combination with conventional antifungal agents in the treatment of disseminated candidiasis in the setting of profound and persistent neutropenia.

The adherence of fluconazole-resistant and fluconazole-susceptible isolates of Candida albicans to explanted rabbit esophageal mucosa was examined in vivo. Among six Candida albicans isolates collected from HIV-infected patients, three fluconazole-resistant (MIC>64 μg/ml) isolates attached more avidly than three fluconazole-susceptible strains (MIC≤0.5 μg/ml) to esophageal mucosa (P≤0.05). When three strains each of six different Candida spp. were compared, the more inherently fluconazole-resistant isolates adhered more avidly in the following order: Candida glabrata>Candida krusei>Candida albicans fluconazole-sensitive >Candida tropicalis>Candida parapsilosis. Nonetheless, fluconazole-resistant Candida albicans demonstrated the greatest degree of adherence in comparison to all fluconazole-susceptible Candidaalbicans (P<0.001) and to all Candida spp. tested (P<0.001). Thus, the refractoriness of esophageal candidiasis in patients infected with fluconazole-resistant isolates may be related to both in vitro drug resistance and increased mucosal adherence.

The activity of liposomal nystatin against invasive pulmonary aspergillosis was investigated in persistently neutropenic rabbits. Treatment groups included liposomal nystatin at dosages of 1, 2 and 4 mg/kg/day intravenously, or amphotericin B deoxycholate 1 mg/kg/day administered intravenously after normal saline loading. As compared with untreated controls, liposomal nystatin administered at 2 and 4 mg/kg/day prolonged survival and reduced fungus-mediated tissue injury and excess lung weight at post-mortem in a similar manner to amphotericin B. Although amphotericin B was superior in clearing infected lung tissue, treatment with all regimens of liposomal nystatin led to a significant reduction in pulmonary fungal tissue burden. During treatment, ultrafast CT-scan demonstrated ongoing resolution of pulmonary lesions at 2 and 4 mg/kg/day, but not at 1 mg/kg/day. With the exception of mild increases in blood urea nitrogen (BUN) and serum creatinine values during treatment at 2 and 4 mg/kg/day, which were similar to those found in amphotericin B-treated rabbits, liposomal nystatin was well tolerated. Preliminary pharmacokinetic studies in non-infected animals established linear drug disposition of liposomal nystatin in plasma over the investigated dosage range and peak plasma levels above the MIC for the test strain after multiple daily dosing for 7 days. Liposomal nystatin increased survival and provided reduced tissue injury, effective microbiological clearance and tolerable side effects in experimental pulmonary aspergillosis in persistently neutropenic rabbits, thus providing a rational basis for further investigations in clinical trials.