Eradication of invasive mucormycosis--effectiveness of the Echinocandin FK463

Acute cutaneous zygomycosis of the scalp: A case report and literature review

Cutaneous zygomycosis is the third most common form of zygomycosis. However, scalp involvement is rare for this disease. In this study, we present a case of acute zygomycosis in a diabetic patient who was effectively treated with local debridement, amphotericin B lipid complex and posaconazole.

Micafungin: the US perspective

Invasive fungal infections cause considerable morbidity and mortality in nosocomial settings and amongst immunocompromised hosts. Invasive candidiasis and aspergillosis remain the most common invasive fungal infections, with Candida spp. constituting the fourth most common bloodstream infection in the USA. Currently available antifungal therapies include the polyene, antimetabolite, allylamine, azole and echinocandin drug classes. Micafungin, approved in March 2005 by the Food and Drug Administration for use in the USA, has shown safety and efficacy for the treatment of candidiasis and aspergillosis in clinical trials in Japan, Europe and South Africa. Micafungin holds promise as a first-line treatment option for candidiasis, as well as prophylaxis against invasive fungal infections during periods of neutropenia in high-risk patients.

Recent advances in antifungal pharmacotherapy for invasive fungal infections

Invasive fungal infections carry significant morbidity and mortality. Candida species have become one of the most frequent causes of bloodstream infections, and infections caused by molds such as Aspergillus are becoming more frequent in immunocompromised patients. As this population grows, more invasive fungal infections can be anticipated. In the past, treatment options have been limited for many of these infections due to toxicity and efficacy concerns with the available antifungals. Fortunately, the past few years have brought exciting developments in antifungal pharmacotherapy. Lipid-based formulations of amphotericin B were introduced in the 1990s to attenuate adverse effects caused by amphotericin B deoxycholate (Fungizone, Bristol-Myers Squibb). Most recently, the echinocandins have been added to our antifungal regimen with the introduction of caspofungin (Cancidas, Merck and Co.) and voriconazole (Vfend, Pfizer), a new triazole, has come to market. The introduction of the echinocandins has invigorated the discussion about combination antifungal therapy. Evidence-based studies using these new agents are accumulating, and they are assuming important roles in the pharmacotherapy of invasive fungal infections in seriously ill and complex patients.

Mucormycosis in immunochallenged patients

Mucorales species are deadly opportunistic fungi with a rapidly invasive nature. A rare disease, mucormycosis is most commonly reported in patients with diabetes mellitus, because the favorable carbohydrate-rich environment allows the Mucorales fungi to flourish, especially in the setting of ketoacidosis. However, case reports over the past 20 years show that a growing number of cases of mucormycosis are occurring during treatment following bone marrow transplants (BMT) and hematological malignancies (HM) such as leukemia and lymphoma. This is due to the prolonged treatment of these patients with steroids and immunosuppressive agents. Liposomal amphotericin B treatment and posaconazole are two pharmacologic agents that seem to be effective against mucormycosis, but the inherently rapid onset and course of the disease, in conjunction with the difficulty in correctly identifying it, hinder prompt institution of appropriate antifungal therapy. This review of the literature discusses the clinical presentation, diagnosis, and treatment of mucormycosis among the BMT and HM populations.

Zygomycetes infections in pediatric hematology oncology patients: a case series and review of the literature

Fungi from the Zygomycetes class are increasingly recognized causes of infection in immunosuppressed children, but no comprehensive literature review and few case series have been published on the topic. A case series of 6 pediatric oncology patients with Zygomycetes infections cared for at our institution was constructed, and a concurrent search of the English language literature for Zygomycetes infections in children with oncologic disorders was undertaken. Our case series described 6 patients (5 male) between the ages of 2.5 and 19.5 years. One patient was diagnosed with rhinocerebral disease, 2 with rhinosinusitis, 2 with pulmonary involvement, and 1 with a gastrointestinal presentation. Five patients survived. Our literature review identified 82 cases from 61 studies. The mean subject age was 10.8 years (1.4 to 21.0 y). About 92.7% of all patients suffered from some form of leukemia, with 70.7% suffering from acute lymphoblastic leukemia. Overall, 58.5% of reported patients survived, with individuals with disseminated disease showing the worst prognosis (68.2% mortality) and those with cutaneous disease the best (14.3% mortality). Survival is increasingly reported in the literature, perhaps as a result of improved diagnostic capabilities, increased physician awareness and increased reliance on adjunctive surgical therapy.

Workload and clinical significance of the isolation of zygomycetes in a tertiary general hospital

Several reports of increases in invasive zygomycosis (IZ) at individual institutions across the USA and Europe have contributed to a generalized concept that IZ is an increasing problem and the overestimation of the clinical significance of the isolation of zygomycetes in microbiology departments. We assessed the workload and clinical significance of zygomycetes isolates recovered from clinical samples in our institution over a 19-year period (1988-2006). We retrospectively reviewed the charts of those patients from who isolates of zygomycetes were obtained and calculated the workload of its isolation, the incidence of IZ during this period and the positive predictive value (PPV) of a positive culture. Zygomycetes were recovered from 210 samples (176 patients), i.e., 0.086/1,000 clinical samples processed and 6.3/1,000 samples submitted for fungal isolation. Zygomycetes represented 0.6% of the total fungi recovered. The mean incidence of the disease was 1.2 cases/100,000 admissions (range 0-20). Only 16 of the samples which grew zygomycetes (7.6%) were from infected patients. The workload generated by zygomycetes in our institution and the PPV for IZ of their isolation in our laboratory were very low and the disease was not found to have significantly increased in recent years in our institution. Data from specific institutions cannot be generalized.

Invasive zygomycosis in transplant recipients

Zygomycosis are rare fungal infections occurring mainly in immunocompromised patients. To date only 160 cases have been published in transplant recipients. We report four new cases of zygomycosis in transplant recipients illustrating the large clinical spectrum of this infection: one disseminated infection with heart involvement and one rhinocerebral infection with dissemination in two bone marrow transplant recipients, one cutaneous infection in a liver and one pulmonary infection in a kidney recipient. All cases, except the cutaneous infection that was accessible to surgical resection and a systemic antifungal treatment, were fatal. In transplant recipients cumulating risk factors for zygomycosis, a high index of suspicion is required. Early diagnosis and combining surgery with systemic amphotericin-B are mandatory to improve survival rates.

Impact of zygomycosis on microbiology workload: a survey study in Spain

This multicenter, population-based study evaluated the laboratory workload produced by zygomycetes and the number of cases of zygomycosis in Spain during 2005. Less than 8% of the patients who harbored zygomycete isolates had zygomycosis. The incidence of zygomycosis (6 cases) was 0.43 cases/1,000,000 inhabitants and 0.62 cases/100,000 hospital admissions.

Emerging echinocandins for treatment of invasive fungal infections

The echinocandins are a new class of antifungals, developed in response to the need for safe and effective antifungals for the treatment of invasive fungal infections. These agents work by inhibiting 1,3-beta-d-glucan synthase, an enzyme essential for production of cell walls in select fungi. Echinocandins appear to demonstrate favourable activity in vitro against a variety of yeasts (including both Candida albicans and non-albicans Candida) as well as select moulds (including Aspergillus spp.) In general, all echninocandins demonstrate a favourable safety profile and require once-daily parenteral administration. Caspofungin is the first of these agents to be available in the US, and is approved for empirical antifungal therapy in febrile neutropenic patients, candidaemia and select forms of invasive candidiasis, and for management of invasive aspergillosis in patients refractory to or intolerant of other therapies. Micafungin was recently approved by the FDA for treatment of oesophageal candidiasis, and for the prophylaxis of fungal infections in haematopoietic stem cell transplant recipients. Emerging data indicate micafungin may have an important role in the treatment of invasive forms of candidiasis. Anidulafungin is an echinocandin approved in the US for treatment of candidaemia and oesophageal candidiasis. Aminocandin (HMR-3702, IP-960) is an investigational agent, with published experience limited to in vitro studies and animal models of infection.

Posaconazole as salvage therapy for zygomycosis

Zygomycosis, an infection that is associated with significant morbidity and mortality, is becoming common in immunocompromised patients. Posaconazole is a new extended-spectrum azole antifungal that has demonstrated in vitro and in vivo activity against zygomycetes. This report provides the results from the first 24 patients with active zygomycosis who were enrolled in two open-label, nonrandomized, multicentered compassionate trials that evaluated oral posaconazole as salvage therapy for invasive fungal infections. Posaconazole was usually given as an oral suspension of 200 mg four times a day or 400 mg twice a day. Eleven (46%) of the infections were rhinocerebral. Duration of posaconazole therapy ranged from 8 to 1,004 days (mean, 292 days; median, 182 days). Rates of successful treatment (complete cure and partial response) were 79% in 19 subjects with zygomycosis refractory to standard therapy and 80% in 5 subjects with intolerance to standard therapy. Overall, 19 of 24 subjects (79%) survived infection. Survival was also associated with surgical resection of affected tissue and stabilization or improvement of the subjects' underlying illnesses. Failures either had worsening of underlying illnesses or requested all therapy withdrawn; none of the failures received more than 31 days of posaconazole. Posaconazole oral solution was well tolerated and was discontinued in only one subject due to a drug rash. Posaconazole appears promising as an oral therapy for zygomycosis in patients who receive required surgery and control their underlying illness.

Empyema thoracis due toRhizopus oryzaein an allogenic bone marrow transplant recipient

We describe a case of empyema thoracis caused by Rhizopus oryzae diagnosed in an allogenic bone marrow transplant patient with acute lymphocytic leukemia. The isolate of R. oryzae was recovered from three pleural effusion specimens, which were black in color. It was identified on the basis of characteristic colonial appearance and microscopic findings, as well as the partial sequencing of rRNA genes. The patient died of uncontrolled R. oryzae empyema thoracis and concomitant nosocomial infection.

A fatal case of disseminated zygomycosis associated with the use of blood glucose self-monitoring equipment

We report a fatal case of disseminated zygomycosis due to Cunninghamella bertholletiae in a 68-year-old man with myelodysplasia and type II diabetes mellitus, receiving desferrioxamine therapy for iron overload secondary to multiple transfusions. It is thought that he acquired the infection through the use of blood glucose self-monitoring equipment.

Novel perspectives on mucormycosis: pathophysiology, presentation, and management

Mucormycosis is a life-threatening fungal infection that occurs in immunocompromised patients. These infections are becoming increasingly common, yet survival remains very poor. A greater understanding of the pathogenesis of the disease may lead to future therapies. For example, it is now clear that iron metabolism plays a central role in regulating mucormycosis infections and that deferoxamine predisposes patients to mucormycosis by inappropriately supplying the fungus with iron. These findings raise the possibility that iron chelator therapy may be useful to treat the infection as long as the chelator does not inappropriately supply the fungus with iron. Recent data support the concept that high-dose liposomal amphotericin is the preferred monotherapy for mucormycosis. However, several novel therapeutic strategies are available. These options include combination therapy using lipid-based amphotericin with an echinocandin or with an azole (largely itraconazole or posaconazole) or with all three. The underlying principles of therapy for this disease remain rapid diagnosis, reversal of underlying predisposition, and urgent surgical debridement.

Management of rare fungal infections

PURPOSE OF REVIEW

Fungal infections caused by rare fungi have increased in recent years. This may be due to the increase in the number of immunocompromised patients. Some rare fungi are geographically restricted, but with globalization and travel these infections are seen worldwide. The aim of this review is to address recent advances in the management of some uncommon fungal infections.

RECENT FINDINGS

Dematiaceous fungi (Phaeohyphomycetes) have been reported in both immunocompromised and immunocompetent individuals. Cerebral involvement and disseminated disease are associated with high mortality rates. Surgical excision and broad-spectrum triazole antifungal therapy are associated with better outcomes. Mucormycosis in diabetic and immune-suppressed patients is associated with high mortality. Early radical surgical debridement and amphotericin B-based regimens are a key to success. Basidiobolomycosis has recently been reported to cause chronic granulomatous infection of the gastrointestinal tract. Treatment with itraconazole and surgical resection is associated with favourable outcomes. Invasive fusariosis in cancer patients is typically resistant to most antifungal agents, but recent data have suggested a response to voriconazole. Voriconazole also demonstrated activity against Scedosporium apiospermum, but was less active against Scedosporium prolificans. Amphotericin B and itraconazole are currently the treatments of choice for the southeast Asian fungus, Penicillium marneffie.

SUMMARY

Parallel to the increased number of patients susceptible to invasive infections has been an increase in the number of broad-spectrum antifungal agents allowing for better therapeutic options. High-quality data are lacking because of the rarity of such infections. In future, new triazoles and echinocandins will probably replace amphotericin B as the first therapeutic choice for many uncommon fungal infections.

Wound infection due toAbsidiacorymbiferaandCandida albicanswith fatal outcome

A case of a mixed infection due to Candida albicans and the zygomycete Absidia corymbifera in a 38-year-old, previously healthy, Caucasian male is presented. The infection developed following serial rib fractures, and ruptures of kidney, liver and biliary tract as well as a pancreatic contusion resulting from a traffic accident. During intensive care treatment the patient underwent several surgical procedures but subsequently experienced multi-organ failure and sepsis. Some weeks later, fungal growth was observed macroscopically on the patient's skin and wounds. From wound swabs C. albicans and A. corymbifera were grown. Histopathology of abdominal tissue yielded pseudohyphae and coenocytic hyphae. Although surgical debridement and antifungal treatment with amphotericin B and 5-flucytosine were started immediately, the patient died in therapy-refractory septic multi-organ failure.