Opportunistic fungal infections: filamentous fungi and cryptococcosis

Older patients with diabetes mellitus or pulmonary diseases and those receiving immunosuppressive drugs are at an increased risk of infection with environmentally-acquired, opportunistic fungal diseases. Aspergillus most often produces invasive pulmonary or sinus infection in severely immuno-compromised patients. Chronic necrotizing pulmonary and sino-orbital aspergillosis present subacutely and are often misdiagnosed. Mucormycosis classically presents with rhinocerebral disease in diabetic patients with ketoacidosis, whereas pulmonary infection mimics invasive pulmonary aspergillosis and occurs mostly in patients who are neutropenic. Cryptococcal meningitis in the older patient may manifest simply as confusion. Amphotericin B is the preferred initial treatment for all three fungal infections.     

Invasive pulmonary aspergillosis due to Aspergillus terreus: 12-year experience and review of the literature

A 12-year retrospective analysis was done to identify and evaluate in detail cases of invasive pulmonary aspergillosis (IPA) caused by Aspergillus terreus. We identified 13 A. terreus infections among 133 total cases of confirmed invasive aspergillosis; 11 were IPA and 2 were primary peritoneal infections. Of the 11 patients with IPA, 7 developed neutropenia during hospitalization, and the remaining four were receiving immunosuppressive agents. Ten patients with IPA died; one liver transplantation patient without neutropenia survived after treatment with amphotericin B, itraconazole, and a pulmonary lobectomy. Six patients developed disseminated disease, with the heart the most common extrapulmonary site identified (four patients). These cases demonstrate that IPA caused by A. terreus rapidly progresses in immunocompromised patients receiving amphotericin B and illustrate the need for sensitive diagnostic tests and more effective antifungal agents.     

Cryptococcal meningitis: the place of itraconazole

Itraconazole, an orally active broad-spectrum triazole antimycotic, has demonstrated anti-Cryptococcus activity in vitro and in animal models of cryptococcal meningitis. The drug has been used by a number of clinical groups for the treatment of cryptococcal meningitis, predominantly in AIDS patients. A problem that has been found with ketoconazole is the relatively low absorption of the drug in AIDS patients. This has resulted in ketoconazole plasma levels below the MIC90 (1-5 micrograms ml-1) needed to eliminate Cryptococcus neoformans. In addition, tissue levels of ketoconazole are lower than plasma levels. For itraconazole, the required MIC90 for Cr. neoformans is 0.1 microgram ml-1, and the plasma levels in AIDS patients receiving 200-400 mg daily, even in the case of reduced absorption, are well above this MIC90. The itraconazole levels in the brain and in the meninges are higher than the plasma levels. Consequently, itraconazole has been considered a valid candidate for studies in patients with cryptococcal meningitis. Various treatment modalities have been used: primary oral therapy alone or in combination with amphotericin B or 5-fluorocytosine (5-FC); maintenance oral therapy after initial treatment with amphotericin B (with or without 5-FC); and first-line intravenous treatment in severely ill patients. The results were evaluated in four different groups. When the drug was given as primary oral therapy without combination with amphotericin B or 5-FC, the results depended greatly on the dose administered and on the life expectancy of the patient at inclusion. In general, daily doses of 400 mg were better than 200-mg doses.(ABSTRACT TRUNCATED AT 250 WORDS)     

Efficacy of itraconazole in the prevention of fungal infections among neutropenic patients with hematologic malignancies and intensive chemotherapy. A double blind, placebo controlled study

We studied the efficacy and safety of itraconazole for the prevention of fungal infection in neutropenic patients given cytotoxic chemotherapy for hematologic malignancies. Patients were randomly allocated to receive either itraconazole (200 mg bd) or placebo in addition to oral amphotericin B until the patient either developed fungal infection or had completed antileukemic treatment. Forty six patients (83 neutropenic episodes) treated with itraconazole and 46 placebo treated patients (84 neutropenic episodes) were evaluable. No specific toxicity was noted. Nine fungal infections developed in the itraconazole group, of which four were histologically or microbiologically proven and 15 in the patients given placebo (eight proven) (p < 0.12). All these patients received IV amphotericin B. The incidence of Candida albicans infections tended to be lower in the itraconazole group, but overall, there was no measurable improvement in the prevention of fungal infections and mortality by itraconazole.     

Invasive sinonasal disease due to Scopulariopsis candida: case report and review of scopulariopsosis

Sinonasal infection with fungi of the order Mucorales--termed mucormycosis or zygomycosis--is sometimes seen in immunosuppressed patients, including those with diabetic ketoacidosis and malignancy. We describe a case of invasive sinonasal infection with Scopulariopsis candida (not among the Mucorales organisms) in a 12-year-old girl who was being treated for non-Hodgkin's lymphoma. Only a few cases of invasive infection with Scopulariopsis species have been reported previously; five of six of these cases were associated with persistent or fatal disease. Our patient survived without undergoing radical surgical debridement and was treated with granulocyte colony-stimulating factor, amphotericin B, and itraconazole; chemotherapy was stopped. In vitro susceptibility testing of our patient's Scopulariopsis isolate showed that it was resistant to amphotericin B and that it was relatively susceptible to itraconazole and miconazole. The case described herein demonstrates the expanding spectrum of fungal organisms that may cause invasive sinonasal infection in immunocompromised hosts and the need for reliable antifungal susceptibility testing.     

Changes in the natural history of invasive pulmonary aspergillosis in neutropenic leukemic patients

We describe five patients with acute leukemia who during the period of chemotherapy-induced neutropenia developed invasive pulmonary aspergillosis. Amphotericin B was initiated early in the febrile neutropenic episode at a dose of 1-1.5 mg/kg per day. Four of the five patients had normal chest films at the time amphotericin B was started and only later developed infiltrates, which subsequently progressed to cavitation formation with resolution of the infiltrates around the cavitations. This is compatible with primary aspergilloma or invasive pulmonary aspergillosis. The patients experienced partial (2 patients) or complete resolution (3 patients) of the process, and none died of the fungal infection. In the past, infection with invasive aspergillosis carried a high mortality. We believe that this positive outcome constitutes a change in the natural history of invasive pulmonary aspergillosis in neutropenic patients as a result of the early initiation of high dose amphotericin B. We recommend the early empiric use of amphotericin B therapy in febrile neutropenic patients not responding to broad-spectrum antibiotics, and that the minimal initial dose be 1 mg/kg per day especially in institutions carrying a high incidence of aspergillosis.     

Report of the first case of invasive fungal sinusitis caused by Scopulariopsis acremonium: review of scopulariopsis infections

Scopulariopsis acremonium is a species of saprophytic fungus not previously reported to cause invasive disease in humans, although invasive infections from other species of Scopulariopsis have been reported and are reviewed. Deep infection with this fungus is associated with a high mortality rate. Invasive fungal sinusitis, in general, is a potentially fatal disease that typically affects immunocompromised patients, such as those receiving intensive chemotherapy or undergoing bone marrow transplantation. We report a case of invasive fungal sinusitis caused by Scopulariopsis acremonium in a patient with leukemia, who was successfully treated with amphotericin B, itraconazole, endoscopic sinus surgery, and granulocyte colony-stimulating factor.     

Isolated bilateral renal aspergillosis: an unusual presentation in an immunocompetent host

A 35 year old apparently immunocompetent farmer developed isolated bilateral renal aspergillosis. He presented with acute renal failure due to granulomatous interstitial nephritis and had bilateral renal abscesses on CT scan. Diagnosis came from renal histology and was confirmed on serology. The patient responded quite satisfactorily to single agent antifungal chemotherapy with IV amphotericin B.     

Liposomal amphotericin B. Therapeutic use in the management of fungal infections and visceral leishmaniasis

Incorporation of amphotericin B into small unilamellar liposomes (AmBisome) alters the pharmacokinetic properties of the drug, but allows it to retain significant in vitro and in vivo activity against fungal species, including Candida, Aspergillus and Cryptococcus, and parasites of the genus Leishmania. Used as prophylaxis against fungal infections in immunocompromised patients, liposomal amphotericin B appeared to reduce the incidence of both fungal colonisation and proven fungal infections, but did not affect overall survival. Empirical therapy with liposomal amphotericin B in immunocompromised adults or children with suspected fungal infections was at least as effective as therapy with conventional amphotericin B. In the largest noncomparative studies, liposomal amphotericin B produced mycological eradication in 40 and 83% of patients with proven Candida infections and 41 and 60% with proven Aspergillus infections; however, these studies included relatively few patients. Mycological eradication rates of 67 to 85% in patients with cryptococcal meningitis have been reported. Liposomal amphotericin B is an effective treatment for visceral leishmaniasis in immunocompetent adults and children, including those with severe or drug-resistant disease. The drug also produces good response rates in immunocompromised patients; however, relapse rates in these patients are high. Liposomal amphotericin B is generally well tolerated. Few patients require discontinuation or dose reduction of the drug because of adverse events. The most frequently reported adverse events are hypokalaemia, nephrotoxicity and infusion-related reactions; however, these occur significantly less often after liposomal amphotericin B than after the conventional formulation of the drug. The acquisition cost of liposomal amphotericin B is higher than that of conventional amphotericin B. Cost-effectiveness analysis did not clearly show an economic benefit for empirical liposomal amphotericin B antifungal therapy in adults; however, one model suggested that initial empirical therapy with the liposomal formulation in children may cost less per cure than initial therapy with the conventional formulation. Liposomal amphotericin B appears to be an effective alternative to conventional amphotericin B in the management of immunocompromised patients with proven or suspected fungal infections. Use of the drug is facilitated by its greatly improved tolerability profile compared with conventional amphotericin B. Because of this, liposomal amphotericin should be preferred to conventional amphotericin B in the management of suspected or proven fungal infections in immunocompromised patients with pre-existing renal dysfunction, amphotericin B-induced toxicity or failure to respond to conventional amphotericin B. Liposomal amphotericin B may also be considered for first- or second-line treatment of immunocompetent patients with visceral leishmaniasis.     

Itraconazole resistance in Aspergillus fumigatus

Invasive aspergillosis is an increasingly frequent opportunistic infection in immunocompromised patients. Only two agents, amphotericin B and itraconazole, are licensed for therapy. Itraconazole acts through inhibition of a P-450 enzyme undertaking sterol 14alpha demethylation. In vitro resistance in Aspergillus fumigatus to itraconazole correlated with in vivo outcome has not been previously described. For three isolates (AF72, AF90, and AF91) of A. fumigatus from two patients with invasive aspergillosis itraconazole MICs were elevated. A neutropenic murine model was used to establish the validity of the MICs. The isolates were typed by random amplification of polymorphic DNA. Analysis of sterols, inhibition of cell-free sterol biosynthesis from [14C] mevalonate, quantitation of P-450 content, and [3H]itraconazole concentration in mycelial pellets were used to determine the mechanisms of resistance. The MICs for the three resistant isolates were >16 microg/ml. In vitro resistance was confirmed in vivo for all three isolates. Molecular typing showed the isolates from the two patients to be genetically distinct. Compared to the susceptible isolate from patient 1, AF72 had a reduced ergosterol content, greater quantities of sterol intermediates, a similar susceptibility to itraconazole in cell-free ergosterol biosynthesis, and a reduced intracellular [3H]itraconazole concentration. In contrast, AF91 and AF92 had slightly higher ergosterol and lower intermediate sterol concentrations, fivefold increased resistance in cell-free systems to the effect of itraconazole on sterol 14alpha demethylation, and intracellular [3H] itraconazole concentrations found in susceptible isolates. Resistance to itraconazole in A. fumigatus is detectable in vitro and is present in wild-type isolates, and at least two mechanisms of resistance are responsible.     

Invasive pulmonary aspergillosis caused by Aspergillus ochraceus

Invasive pulmonary aspergillosis (IPA) is a frequent complication in patients with severe neutropenia resulting from cytotoxic chemotherapy. In Europe, Aspergillus fumigatus is most common pathogen of IPA. In our case, IPA was recognised in 54 year old female suffering from acute lymphoblastic leukemia with pancytopenia. The patient developed severe granulocytopenia during chemotherapy. Chest radiograph revealed progressive bilateral infiltrations with cavitation. In sputum culture Aspergillus ochraceus was found. The results of precipitating tests were positive for A. ochraceus and A. fumigatus. Treatment with amphotericin B was used successfully leading soon to clinical improvement, yet radiological lesions remained largely unchanged. The patient received itraconazole, which was very effective and caused almost complete regression. Two episodes of IPA recurrence were treated with antifungal therapy with good results.     

Fatal pulmonary infection caused by the basidiomycete Hormographiella aspergillata

A fatal case of a pulmonary infection caused by Hormographiella aspergillata, the anamorph of the mushroom Coprinus cinereus, is reported for a patient receiving treatment for a second relapse of acute lymphoblastic leukemia. The filamentous basidiomycete was identified with restriction fragment length polymorphism patterns of PCR-amplified internally transcribed spacers and small subunit ribosomal DNA with four restriction enzymes. The patient failed to respond to treatment with amphotericin B and itraconazole. The fungus was cultured from the lungs at autopsy: the MIC of amphotericin B for the fungus was low (0.5 mg/liter), and that of itraconazole was high (8 mg/liter).     

Nickel and gold in skin lesions of pierced earlobes with contact dermatitis. A study using scanning electron microscopy and x-ray microanalysis

OBJECTIVE: To make an analysis of fungemia in HIV-infected patients in our hospital. PATIENTS AND METHODS: We retrospectively (1989-1997) studied all HIV-infected patients with positive blood cultures for Candida sp., Cryptococcus neoformans or any other fungal infection. RESULTS: C. neoformans was isolated in 11 patients (10 men and 1 woman): Six were treated with amphotericin B and 5 with fluconazole. 2 patients died during the acute phase and the infection relapsed in 3. Blood culture for Candida sp. were positive in 9 (8 men and 1 woman): only a case was nosocomial. Seven patients were intravenous drug users and the presenting manifestations were autolimited candidemia in 3, aortic and tricuspid endocarditis in 1 and 2 cases respectively and pneumonia in another one. Six C. albicans, 2 C. krusei and 1 C. glabrata were isolated. 3 patients received amphotericin B and 3 received fluconazole. 2 patients suffering from endocarditis died and so did the patient with C. glabrata infection. A patient, who denied having travelled to endemic areas, developed histoplasmosis; blood culture was positive for H. capsulatum. He initially had a good response to amphotericin B and itraconazole. CONCLUSIONS: Fungemia is not frequent in HIV-infected patients. Cryptococcosis and histoplasmosis occur in advanced HIV-patients and candidemia is fundamentally associated with intravenous drug use.     

Mortality of chromium plating workers in Japan--a 16-year follow-up study

Opportunistic infections are common and major causes of morbidity in patients with AIDS. Endemic mycoses pose serious risks for patients in certain parts of the world. Histoplasmosis occurs in 2-5% of patients with AIDS in the Ohio and Mississippi River valleys of the United States and in over 25% of patients from a few cities. Antigen testing has become a highly useful method for diagnosing histoplasmosis rapidly, evaluating the response to treatment and diagnosing relapse. Treatment with amphotericin B or itraconazole is effective (90% or higher) if the patient is not seriously ill at the time of diagnosis but the mortality approaches 50% for those with multiorgan failure. Itraconazole blood levels should be monitored and drugs that impair the absorption or accelerate the metabolism of itraconazole should be avoided. Prophylaxis with itraconazole may be appropriate in areas with an incidence of histoplasmosis. A recently completed study in cities which have unusually high rates of histoplasmosis will provide greater insight into the role of prophylactic antifungal therapy.     

Interactions of itraconazole with amphotericin B in the treatment of murine invasive candidiasis

The interactions of amphotericin B and itraconazole were studied in murine invasive candidiasis. Candida albicans-infected mice were treated for 10 consecutive days, 24 h after infection. Survival was monitored over 30 days and kidney cultures were done. Mice treated with amphotericin B (0.2 mg/kg/day intraperitoneally) or itraconazole (100 mg/kg/day by oral gavage in two divided doses/ day) had a 30-day survival of 20% or 40%. Concomitant administration of both drugs resulted in 100% mortality; 90% of mice treated with amphotericin B (1 mg/kg/day) survived. With the combination, 100% were dead by day 28 (P < or = .001 vs. amphotericin B). With sequential therapy (i.e., 5 days with one drug and then 5 days with the other), survival was inferior to that with amphotericin B alone but similar to that with itraconazole alone. Kidney culture results confirmed the antagonism of the combination compared with amphotericin B alone. In treatment of murine invasive candidiasis, the concomitant or sequential use of amphotericin B and itraconazole results in a negative interaction.     

Comparison of a new triazole antifungal agent, Schering 56592, with itraconazole and amphotericin B for treatment of histoplasmosis in immunocompetent mice

A murine model of intratracheally induced histoplasmosis was used to evaluate a new triazole antifungal agent, Schering (SCH) 56592, for treatment of histoplasmosis. MICs were determined for SCH 56592, amphotericin B, and itraconazole by testing yeast-phase isolates from 20 patients by a macrobroth dilution method. The MICs at which 90% of the isolates are inhibited were for 0.019 microgram/ml for SCH 56592, 0.5 microgram/ml for amphotericin B, and < or = 0.019 microgram/ml for itraconazole. Survival studies were done on groups of 10 B6C3F1 mice with a lethal inoculum of 10(5). All mice receiving 5, 1, or 0.25 mg of SCH 56592 per kg of body weight per day, 2.5 mg of amphotericin B per kg every other day (qod), or 75 mg of itraconazole per kg per day survived to day 29. Only 44% of mice receiving 5 mg of itraconazole/kg/day survived to day 29. Fungal burden studies done in similar groups of mice with a sublethal inoculum of 10(4) showed a reduction in CFUs and Histoplasma antigen levels in lung and spleen tissue in animals treated with 2 mg of amphotericin B/kg qod, 1 mg of SCH 56592/kg/day, and 75 mg of itraconazole/kg/day, but not in those treated with lower doses of the study drugs (0.2 mg of amphotericin B/kg qod, 0.1 mg of SCH 56592/kg/day, or 10 mg of itraconazole/kg/day). Serum drug concentrations were measured 3 and 24 h after the last dose in mice (groups of five to seven mice), each treated for 7 days with SCH 56592 (10 and 1 mg/kg/day) and itraconazole (75 and 10 mg/kg/day). Mean levels measured by bioassay were as follows: SCH 56592, 10 mg/kg/day (2.15 micrograms/ml at 3 h and 0.35 microgram/ml at 24 h); SCH 56592, 1 mg/kg/day (0.54 microgram/ml at 3 h and none detected at 24 h); itraconazole, 75 mg/kg/day (22.53 micrograms/ml at 3 h and none detected at 24 h); itraconazole, 10 mg/kg/day (1.33 micrograms/ml at 3 h and none detected at 24 h). Confirmatory results were obtained by high-pressure liquid chromatography assay. These studies show SCH 56592 to be a promising candidate for studies of treatment of histoplasmosis in humans.     

Amphotericin-B colloidal dispersion. A review of its use against systemic fungal infections and visceral leishmaniasis

Formulation of amphotericin B with sodium cholesteryl sulphate alters the pharmacokinetic properties of the drug, particularly reducing its distribution to the kidneys. The antifungal activity in vitro of amphotericin B colloidal dispersion (ABCD) is similar to that of conventional amphotericin B (C-AmB) against true pathogenic organisms including Blastomyces, Coccidioides, Histoplasma and Paracoccidioides species and the opportunistic organisms such as Candida and Cryptococcus species. In animal models, ABCD was generally less effective than an identical dose of C-AmB, but overall was more effective because of its improved therapeutic index. Although ABCD appeared to be more effective than C-AmB in resolving infection and improving survival in patients with proven or probable invasive aspergillosis, the retrospective design of the study and the greater prevalence of neutropenia in patients treated with the conventional formulation necessitate cautious interpretation of the results. ABCD has been effective and seldom caused nephrotoxicity in patients with fungal infection who had previously failed to adequately respond or had developed renal toxicity with C-AmB. Similarly, ABCD was effective in patients with proven or suspected fungal infection after bone marrow transplantation. Preliminary results from a pilot study comparing ABCD and C-AmB in patients with neutropenia and persistent fever reported similar response rates with both formulations. ABCD is an effective treatment for visceral leishmaniasis in immunocompetent patients. In 1 study, about 12% of ABCD recipients discontinued the drug because of adverse events; infusion-related events were the most common cause of discontinuation. The renal tolerability of ABCD is better than that of C-AmB. ABCD appears to be an effective alternative to conventional amphotericin B in patients with invasive aspergillosis or visceral leishmaniasis and in those with proven or suspected systemic fungal infection who are intolerant of the conventional formulation or have pre-existing renal impairment. Preliminary data also suggest that ABCD is an alternative to C-AmB when used empirically in patients with neutropenia and fever. Nevertheless, the efficacy of ABCD compared with that of the conventional formulation has yet to be adequately demonstrated and the role of ABCD relative to that of liposomal and other lipid-based formulations has not been determined. CONCLUSIONS: ABCD, like other lipid-based and liposomal formulations of amphotericin B, has been designed to deliver the active drug to the target site, while reducing renal toxicity. The aim of increasing the therapeutic index compared with C-AmB has been achieved.     

Aspergillus laryngotracheobronchitis presenting as stridor in a patient with peripheral T cell lymphoma

Invasive aspergillosis is a serious opportunistic infection in immunocompromised patients. The case history is described of a 44 year old patient with peripheral T cell lymphoma who developed hoarseness and stridor after chemotherapy. Aspergillus fumigatus was isolated repeatedly from the sputum. Bronchoscopic examination showed symmetrical creamy-white exophytic lesions involving both vocal cords and the supraglottic area. There was diffuse tracheobronchitis with multiple raised cream-coloured plaques in the trachea which histologically consisted of numerous septate branching hyphae consistent with Aspergillus species. The lesions responded to systemic treatment with amphotericin B.     

Pulmonary infections in immunosuppressed patients

Pulmonary infections continue to be a significant problem in patients immunosuppressed by cancer or by drugs given for malignancy, or rheumatologic or dermatologic problems. For the neutropenic patient, single-drug rather than combination antibiotic therapy is being increasingly used. The role of growth factors is also being defined. The availability of the new azoles and of alternative forms of amphotericin B have increased treatment options, particularly for invasive pulmonary aspergillosis. Pneumocystis carinii pneumonia continues to be a problem in this population, and controversy remains about the mode of transmission and the mechanism of disease caused by this infection. Exogenous infection rather than reactivation may play a small role. Appreciation of the role of community and opportunistic viruses in causing respiratory infection or other complications in the immunosuppressed population is also being further detailed.     

Invasive pulmonary aspergillosis: a study of 33 cases

Invasive pulmonary aspergillosis (IPA) is an infectious complication appearing mainly in immunosuppressed patients, whose diagnosis is often difficult and lately made, and that usually bears a dismal prognosis. Patients diagnosed as having IPA from 1989 to 1994 were retrospectively analyzed. Probable IPA was diagnosed on the basis of a positive culture for Aspergillus together with a consistent radiological image. Confirmed IPA was diagnosed if there was, in addition to the former, a pathological examination showing Aspergillus hifae invading pulmonary parenchyma and/or pulmonary vessels. There were 25 men and 8 women with a mean age of 53.7 +/- 16.9 years (range: 22-86 years). IPA was confirmed in 11 cases and probable in 22. Sixty three percent of the patients had hematologic malignancy or solid cancer, whereas 30.3% did not have prior granulocytopenia or immunosuppressive therapy. The mean (SD) interval between admission and diagnosis was 40.2 (37.1) days (range: 1-180 days), and the diagnosis was made while the patient was still alive in 75% of the cases. Fifteen percent of the patients had extrapulmonary aspergillosis. The most frequent finding both on X-ray film of the chest and pulmonary computed tomography were bilateral multiple pulmonary nodules. Thirteen patients were treated with itraconazole, 6 with amphotericin B, 5 received both drugs, and 2 received fluconazole. Nineteen patients (57.6%) died and the case-fatality rate among treated patients was 46.1%. IPA presents mainly in immunosuppressed patients, but there was a not negligible proportion of patients lacking the classical risk factors. IPA is often a lately made diagnosis and in a quarter of the patients it is not made when the patient is alive. The most frequent radiological presentation are multiple bilateral nodules. The case-fatality rate of IPA is exceedingly high, even when if the patient has been adequately treated.