micafungin and Esophagitis

Micafungin is a selective inhibitor of the synthesis of fungal 1,3-β-D-glucan, an essential component of the fungal cell wall. It is available as a powder for infusion only and is registered for the treatment of invasive and esophageal candidiasis in addition to prophylaxis of Candida infections in both adults and children. Average exposure after a single intravenous 100 mg dose in healthy adults is 133 mg h/L. Both exposure and maximum plasma concentration show linear dose proportional pharmacokinetics (PK) over a 0.15-8 mg/kg dose range. In healthy adults, the clearance (CL) is 10.4 mL/h/kg and volume of distribution is 0.2 L/kg; both are independent of the dose. Micafungin is metabolized by arylsulfatase, catechol-O-methyltransferase, and several cytochrome P450 (CYP) isoenzymes (3A4, 1A2, 2B6 and 2C), but no dose adjustments are necessary in patients with (severe) hepatic dysfunction. Exposure to micafungin is lower in hematology patients, and is even further lowered in critically ill patients (including burn patients) compared with healthy volunteers, which might have consequences for treatment efficacy. In children, an increased CL has been reported: 40-80 mL/h/kg in premature neonates and 20 mL/h/kg in children >4 months of age. Therefore, relatively higher doses of 4-10 mg/kg in premature neonates and 2-4 mg/kg in children with invasive candidiasis are used. However, these higher CLs may also be explained by the eightfold higher free fraction of unbound micafungin in premature neonates, meaning that an augmented dose might not be required.

Topics: Adult; Antifungal Agents; Candidiasis; Candidiasis, Invasive; Child; Critical Illness; Dose-Response Relationship, Drug; Esophagitis; Humans; Infant; Infant, Newborn; Micafungin

Micafungin is a semisynthetic lipopeptide developed from Coleophoma empetri, which blocks the synthesis of β-1,3-D-glucan, an essential component of the fungal wall, though non-competitive inhibition of β-1,3-D-glucan synthetase. Micafungin is a dose-dependent candidacidal agent with excellent in vitro efficacy against most Candida spp. including species resistant to amphotericin B, such as Candida lusitaniae, several azoles, such as C. glabrata or C. krusei, and isolates not susceptible to other echinocandins. Moreover, this drug is active against Candida biofilms. Micafungin is a first-line drug for the treatment of candidemias and invasive candidiasis in adults and children (including neonates). This drug is approved for use in the treatment of invasive candidiasis and Candida esophagitis, as well as in the prophylaxis of Candida infections in hematopoietic stem cell transplant recipients or those at risk of prolonged neutropenia. Micafungin can be used both in the treatment and prevention of candidiasis in neonates, children, adolescents, adults, and the elderly, making it highly useful in patient groups in which the use of other antifungal drugs has not been authorized.

Topics: Adolescent; Adult; Aged; Animals; Antifungal Agents; Biofilms; Candida; Candidiasis, Invasive; Cell Wall; Child; Child, Preschool; Clinical Trials as Topic; Double-Blind Method; Drug Evaluation, Preclinical; Echinocandins; Esophagitis; Fungal Proteins; Glucosyltransferases; Humans; Immunocompromised Host; Infant; Infant, Newborn; Lipopeptides; Micafungin; Mice; Middle Aged; Multicenter Studies as Topic; Postoperative Complications; Species Specificity; Transplantation; Young Adult

There have been over 80 documented cases of swallow syncope-a rare form of reflex or neurally mediated syncope-with most cases associated with an underlying esophageal disorder. Here, we describe the first reported case of swallow syncope or presyncope caused by an infectious esophagitis. Our 65-year-old patient initially developed dysphagia, odynophagia, and presyncope with swallowing. This lead to nutrition and medication avoidance behavior, which was followed by the development of diabetic ketoacidosis. The diagnosis of swallow presyncope was confirmed with a provocative swallow study demonstrating 8 s sinus arrest, and an underlying cause of Candida esophagitis was found by upper endoscopy. Symptoms completely resolved after treatment with micafungin.

Topics: Aged; Antifungal Agents; Candida; Candidiasis; Deglutition Disorders; Diabetic Ketoacidosis; Esophagitis; Female; Humans; Micafungin; Syncope

To illustrate the progressive loss of cross-echinocandin activity on Candida albicans isolates with strong clonal homology from a patient with advanced HIV infection and chronic oesophagitis progressively resistant to uninterrupted micafungin treatment.. Antifungal susceptibility profiles for different antifungal agents were determined against serial C. albicans isolates retrieved before and during therapy. Multilocus sequencing typing (MLST) was performed on each of the isolates. FKS1 mutations conferring reduced susceptibility to echinocandin drugs were determined by DNA sequence analysis.. Four C. albicans isolates showing identical allelic homology were retrieved from the patient at the initiation and during therapy with micafungin. The progressive lack of clinical response to micafungin therapy was associated with increased MICs of all three echinocandin drugs (caspofungin, micafungin and anidulafungin) in association with the acquisition of mutations in the FKS1 gene.. This report documents for the first time a progressive loss of activity of all three echinocandin drugs against clonally related C. albicans isolates following long-term clinical exposure to this new class of antifungal agents.

Topics: Adult; AIDS-Related Opportunistic Infections; Antifungal Agents; Candida albicans; Candidiasis; Drug Resistance, Fungal; Echinocandins; Esophagitis; Fatal Outcome; Glucosyltransferases; HIV Infections; Humans; Lipopeptides; Lipoproteins; Male; Membrane Proteins; Micafungin; Microbial Sensitivity Tests; Peptides, Cyclic; Saccharomyces cerevisiae Proteins