Pancreatic toxicity after liposomal amphotericin B

Pancreas preservation with amphotericin B deteriorates islet yield for porcine islet isolation

BACKGROUND

Amphotericin B is a crucial agent in the management of serious systemic fungal infections. It is also known to be cytotoxic. In this study, we evaluated the effect of amphotericin B added to the preservation solution on islet yield during islet isolation.

METHODS

Porcine pancreata were preserved in the preservation solution with or without amphotericin B (0.25 μg/mL) for approximately 18 hours at 4°C, and then islet isolation was performed. An optimized number (1750 IE) of isolated islets from each group were transplanted into streptozotocin-induced diabetic mice. The culture of isolated islets and acinar tissue with amphotericin B was also evaluated.

RESULTS

The islet yield before and after purification in the amphotericin B (-) group was significantly higher than that in the amphotericin B (+) group. After islet transplantation into diabetic mice, blood glucose levels reached the normoglycemic range, with 50% and 0% of that of the diabetic mice in the amphotericin B (-) and amphotericin B (+) groups, respectively. In the culture study, amphotericin B was found to be cytotoxic to porcine islets and acinar tissue.

CONCLUSIONS

Amphotericin B added to the preservation solution deteriorates islet yield during porcine islet isolation. Thus, the use of amphotericin B should be considered carefully for the preservation of the pancreas for islet isolation and islet culture before islet transplantation.

Clinical Pharmacokinetics, Pharmacodynamics, Safety and Efficacy of Liposomal Amphotericin B

Since its introduction in the 1990s, liposomal amphotericin B (LAmB) continues to be an important agent for the treatment of invasive fungal diseases caused by a wide variety of yeasts and molds. This liposomal formulation was developed to improve the tolerability of intravenous amphotericin B, while optimizing its clinical efficacy. Since then, numerous clinical studies have been conducted, collecting a comprehensive body of evidence on its efficacy, safety, and tolerability in the preclinical and clinical setting. Nevertheless, insights into the pharmacokinetics and pharmacodynamics of LAmB continue to evolve and can be utilized to develop strategies that optimize efficacy while maintaining the compound's safety. In this article, we review the clinical pharmacokinetics, pharmacodynamics, safety, and efficacy of LAmB in a wide variety of patient populations and in different indications, and provide an assessment of areas with a need for further clinical research.

Enhancing adverse drug event detection in electronic health records using molecular structure similarity: application to pancreatitis

Background

Adverse drug events (ADEs) detection and assessment is at the center of pharmacovigilance. Data mining of systems, such as FDA’s Adverse Event Reporting System (AERS) and more recently, Electronic Health Records (EHRs), can aid in the automatic detection and analysis of ADEs. Although different data mining approaches have been shown to be valuable, it is still crucial to improve the quality of the generated signals.

Objective

To leverage structural similarity by developing molecular fingerprint-based models (MFBMs) to strengthen ADE signals generated from EHR data.

Methods

A reference standard of drugs known to be causally associated with the adverse event pancreatitis was used to create a MFBM. Electronic Health Records (EHRs) from the New York Presbyterian Hospital were mined to generate structured data. Disproportionality Analysis (DPA) was applied to the data, and 278 possible signals related to the ADE pancreatitis were detected. Candidate drugs associated with these signals were then assessed using the MFBM to find the most promising candidates based on structural similarity.

Results

The use of MFBM as a means to strengthen or prioritize signals generated from the EHR significantly improved the detection accuracy of ADEs related to pancreatitis. MFBM also highlights the etiology of the ADE by identifying structurally similar drugs, which could follow a similar mechanism of action.

Conclusion

The method proposed in this paper provides evidence of being a promising adjunct to existing automated ADE detection and analysis approaches.

Endocrine and metabolic manifestations of invasive fungal infections and systemic antifungal treatment

Systemic fungal infections are increasingly reported in immunocompromised patients with hematological malignancies, recipients of bone marrow and solid organ allografts, and patients with AIDS. Mycoses may infiltrate endocrine organs and adversely affect their function or produce metabolic complications, such as hypopituitarism, hyperthyroidism or hypothyroidism, pancreatitis, hypoadrenalism, hypogonadism, hypernatremia or hyponatremia, and hypercalcemia. Antifungal agents used for prophylaxis and/or treatment of mycoses also have adverse endocrine and metabolic effects, including hypoadrenalism, hypogonadism, hypoglycemia, dyslipidemia, hypernatremia, hypocalcemia, hyperphosphatemia, hyperkalemia or hypokalemia, and hypomagnesemia. Herein, we review how mycoses and conventional systemic antifungal treatment can affect the endocrine system and cause metabolic abnormalities. If clinicians are equipped with better knowledge of the endocrine and metabolic complications of fungal infections and antifungal therapy, they can more readily recognize them and favorably affect outcome.

Acute Pancreatitis in a Patient Treated with Micafungin

CASE SUMMARY

A 73-year-old man (height, 158.2 cm; weight, 49.8 kg) presented with upper abdominal tenderness after 3 weeks of treatment with 150 mg/d of micafungin (3 mg/kg . d) (Mycamine, Astellas Pharma US Inc., Deerfield, Illinois) intravenously for pulmonary aspergillosis accompanied by [DOSAGE ERROR CORRECTED] pulmonary Mycobacterium avium complex (MAC) infection. Pulmonary aspergillosis was noninvasively diagnosed by a fungus lump in a cavity in the right upper lung field with a high value of 1,3-beta-D-glucan and a positive result for aspergillosis antigen. The patient had a medical history of gastrectomy due to gastric cancer and idiopathic thrombocytopenic purpura (ITP). He had been prescribed 800 mg/d of clarithromycin, 400 mg/dL of rifampicin, and 750 mg/d of ethambutol hydrochloride for pulmonary MAC infection for 2 years and 5 mg/d of prednisolone for ITP for 7 years. No traditional or homeopathic medicine had been received/administered. Laboratory tests at the onset of abdominal pain revealed a white blood cell count of 4300/microL with 51% neutrophils. There was no eosinophilia. Platelet count was 15,100/muL, with normal coagulation. Immunoglobulin G and immunoglobulin M were 1720 and 154 mg/dL, respectively. The patient had no history of allergy, biliary tract disease, hyperlipidemia, or hypercalcemia. He did not report alcohol use. The laboratory findings, magnetic resonance imaging, and upper abdominal tenderness were consistent with acute pancreatitis. After cessation of all drugs, his symptoms improved with bowel rest and parenteral nutrition. His laboratory measurements normalized thereafter. All drugs, except micafungin, were readministered for pulmonary MAC infection and ITP, and itraconazole was administered for pulmonary aspergillosis after the recovery from pancreatitis. During 16 months of follow-up, the pancreatitis did not recur.

DISCUSSION

We performed a literature search of all available English-language articles published on MEDLINE between January 1966 and January 2007 using the key terms micafungin (text and indexed terms) and pancreatitis (text and indexed terms). Based on the search of MEDLINE, there have been no reports of acute pancreatitis associated with micafungin. The Naranjo adverse drug reaction (ADR) probability scale was used to assess the probability of micafungin-associated acute pancreatitis. A score of 6 was obtained, indicating a probable ADR from micafungin treatment.

CONCLUSION

We report a case of acute pancreatitis probably associated with micafungin use in an elderly patient.

Antifungal effects of aminosulphoxide and disulphide derivatives

2-Benzenesulphinyl-(1,4)-naphtoquinone and 14 derivatives were synthesised and were used to evaluate their cytotoxicity against a human myelomonocyte cell line and their antifungal activity against two yeast, i.e. Candida albicans and C. tropicalis and against two filamentous fungi such as Aspergillus niger and Fusarium oxysporum and against one dermatophyte, namely Trichophyton tonsurans. The cytotoxicity and antifungal activities were investigated in comparison with amphotericin B as reference drug. No compound was significantly more toxic than amphotericin B at 0.2 microg ml(-1). The best results of antifungal activity were obtained with GFL 10, GFL 13 and GFL 30 on C. tropicalis, F. oxysporum and T. tonsurans. For C. albicans and A. niger, there was no difference between amphotericin B and the other molecules. The sterol quantitation, the time-kill curves were carried out for these three compounds in order to confirm their action in ergosterol synthesis. Time-kill curves showed a fungistatic activity. For C. tropicalis GFL 10, GFL 13 and GFL 30 increased the growth delay better than amphotericin B, in contrast to F. oxysporum. As for T. tonsurans, GFL10 and GFL13 gave a delay, but the effect of GFL 30 was a bit less marked.

Acute 40 percent exchange-transfusion with hemoglobin-vesicles (HbV) suspended in recombinant human serum albumin solution: degradation of HbV and erythropoiesis in a rat spleen for 2 weeks

BACKGROUND

Hemoglobin-vesicles (HbVs; diameter, 251 +/- 81 nm) are artificial O(2) carriers. Their efficacy for acute exchange transfusion has been characterized in animal models. However subsequent profiles of recovery involving the degradation of HbV in the reticuloendothelial system (RES) and hematopoiesis remain unknown.

STUDY DESIGN AND METHODS

Isovolemic 40 percent exchange transfusion was performed in 60 male Wistar rats with HbV suspended in 5 g per dL recombinant human serum albumin (rHSA; HbV/rHSA, [Hb] = 8.6 g/dL), stored rat RBCs suspended in rHSA (sRBC/rHSA), or rHSA alone. Hematological and plasma biochemical analyses and histopathological examination focusing on the spleen were conducted for the subsequent 14 days.

RESULTS

The reduced hematocrit (Hct) level (26%) for the HbV/rHSA and rHSA groups returned to its original level (43%) in 7 days. Plasma erythropoietin was elevated in all groups: the rHSA group showed the highest value on Day 1 (321 +/- 123 mIU/mL) relating to the anemic conditions (HbV/rHSA, 153 +/- 22; sRBC/rHSA, 63 +/- 7; baseline, 21 +/- 3). Simultaneously, splenomegaly occurred in all the groups as HbV/rHSA > rHSA > sRBC/rHSA. Histopathologically, the accumulated HbV in the spleen was undetectable by Day 14, but hemosiderin was deposited in slight quantities for both the HbV/rHSA and sRBC/rHSA groups. Considerable amounts of erythroblasts were apparent in the spleens of both the rHSA and the HbV/rHSA groups.

CONCLUSION

HbVs were phagocytized and degraded in RES, a physiological compartment for the degradation of RBCs, and the elevated erythropoietic activity resulted in the complete recovery of Hct within 7 days in the rat model.

Physiological Capacity of the Reticuloendothelial System for the Degradation of Hemoglobin Vesicles (Artificial Oxygen Carriers) after Massive Intravenous Doses by Daily Repeated Infusions for 14 Days

A hemoglobin vesicle (HbV; diameter 252 +/- 53 nm) or liposome-encapsulated Hb is an artificial oxygen carrier developed for use as a transfusion alternative, and its oxygen-transporting capacity has been well characterized, although critical physiological compartments for the Hb degradation after a massive infusion of HbV and the safety outcome remain unknown. In this study, we aimed to examine the compartments for its degradation by daily repeated infusions (DRI) of HbV, focusing on its influence on the reticuloendothelial system (RES). Male Wistar rats intravenously received the HbV suspension at 10 ml/kg/day for 14 consecutive days. The cumulative infusion volume (140 ml/kg) was equal to 2.5 times the whole blood volume (56 ml/kg). The animals tolerated the DRI well and survived, and body weights continuously increased. One day after DRI, hepatosplenomegaly occurred significantly through the accumulation of large amounts of HbV. Plasma clinical chemistry was overall normal, except for a transient elevation of lipid components derived from HbV. These symptoms subsided 14 days after DRI. Hemosiderin deposition and up-regulation of heme oxygenase-1 coincided in the liver and spleen but were not evident in the parenchyma of these organs. Furthermore, the plasma iron and bilirubin levels remained unchanged, suggesting that the heme-degrading capacity of the RES did not surpass the ability to eliminate bilirubin. In conclusion, phospholipid vesicles for the encapsulation of Hb would be beneficial for heme detoxification through their preferential delivery to the RES, a physiological compartment for degradation of senescent RBCs, even at doses greater than putative clinical doses.

Metabolism of hemoglobin-vesicles (artificial oxygen carriers) and their influence on organ functions in a rat model

Phospholipid vesicles encapsulating Hb (Hb-vesicles: HbV) have been developed for use as artificial O(2) carriers (250 nm phi). As one of the safety evaluations, we analyzed the influence of HbV on the organ functions by laboratory tests of plasma on a total of 29 analytes. The HbV suspension ([Hb]=10 g/dl) was intravenously infused into male Wistar rats (20 ml/kg; whole blood = 56 ml/kg). The blood was withdrawn at 8h, and 1, 2, 3, and 7 days after infusion, and the plasma was ultracentrifuged to remove HbV in order to avoid its interference effect on the analytes. Enzyme concentrations, AST, ALT, ALP, and LAP showed significant, but minor changes, and did not show a sign of a deteriorative damage to the liver that was one of the main organs for the HbV entrapment and the succeeding metabolism. The amylase and lipase activities showed reversible changes, however, there was no morphological changes in pancreas. Plasma bilirubin and iron did not increase in spite of the fact that a large amount of Hb was metabolized in the macrophages. Cholesterols, phospholipids, and beta-lipoprotein transiently increased showing the maximum at 1 or 2 days, and returned to the control level at 7 days. They should be derived from the membrane components of HbV that are liberated from macrophages entrapping HbV. Together with the previous report of the prompt metabolism of HbV in the reticuloendothelial system by histopathological examination, it can be concluded that HbV infusion transiently modified the values of the analytes without any irreversible damage to the corresponding organs at the bolus infusion rate of 20 ml/kg.