Invasive Fusariosis in Patients with Hematologic Diseases

Fusarium species are filamentous fungi widely encountered in nature, and may cause invasive disease in patients with hematologic conditions. Patients at higher risk are those with acute leukemia receiving induction remission chemotherapy or allogeneic hematopoietic cell transplant recipients. In these hosts, invasive fusariosis presents typically with disseminated disease, fever, metastatic skin lesions, pneumonia, and positive blood cultures. The prognosis is poor and the outcome is largely dependent on the immune status of the host, with virtually a 100% death rate in persistently neutropenic patients, despite monotherapy or combination antifungal therapy. In this paper, we will review the epidemiology, clinical manifestations, diagnosis, and management of invasive fusariosis affecting patients with hematologic diseases.

Osteomyelitis caused by Sporothrix schenckii in an immunocompetent patient

Sporotrichosis is the most common subcutaneous mycosis in South America and its association with zoonotic transmission remains a relevant public health problem in Rio de Janeiro, Brazil. The disease most commonly presents as subacute or chronic cutaneous lesions, although dissemination to various organs and systems occurs in rare cases, mainly in immunosuppressed individuals. This report describes a case of sporotrichosis with severe bone and subcutaneous damage in an immunocompetent patient who did not exhibit the characteristic skin lesions of sporotrichosis, including ulcers, nodules, and lymphangitis.

Increased incidence of invasive fusariosis with cutaneous portal of entry, Brazil

Most cases of infection with Fusarium spp. fungi involved primary skin lesions.

Invasive fusariosis (IF) is an infection with Fusarium spp. fungi that primarily affects patients with hematologic malignancies and hematopoietic cell transplant recipients. A cutaneous portal of entry is occasionally reported. We reviewed all cases of IF in Brazil during 2000–2010, divided into 2 periods: 2000–2005 (period 1) and 2006–2010 (period 2). We calculated incidence rates of IF and of superficial infections with Fusarium spp. fungi identified in patients at a dermatology outpatient unit. IF incidence for periods 1 and 2 was 0.86 cases versus 10.23 cases per 1,000 admissions (p<0.001), respectively; superficial fusarial infection incidence was 7.23 versus 16.26 positive cultures per 1,000 superficial cultures (p<0.001), respectively. Of 21 cases of IF, 14 showed a primary cutaneous portal of entry. Further studies are needed to identify reservoirs of these fungi in the community and to implement preventive measures for patients at risk.

Molecular analyses of Fusarium isolates recovered from a cluster of invasive mold infections in a Brazilian hospital

Background

Invasive fusariosis (IF) is a rare but often fatal fungal infection in immunosuppressed patients. In 2007, cases of IF above the expected epidemiologic baseline were detected in the hematology ward of a hospital in Rio de Janeiro, Brazil. Possible sources of infection were investigated by performing environmental sampling and patient isolate collection, followed by molecular typing. Isolates from dermatology patients with superficial fusariosis were included in the study for comparison to molecular types found in the community.

Methods

Environmental sampling focused on water-related sources in and around the hematology ward. Initially, we characterized 166 clinical and environmental isolates using the Fusarium translation elongation factor 1α (EF-1α) genetic locus. Isolates included 68 collected from water-related sources in the hospital environment, 55 from 18 hematology patients, and 43 from the skin/nails of 40 outpatients seen at the hospital dermatology clinic. Multi-locus sequence typing was performed on Fusarium solani species complex (FSSC) species 1 and 2 isolates to investigate their relatedness further.

Results

Most of the hematology samples were FSSC species 2, with species type FSSC 2-d the most commonly isolated from these patients. Most of the outpatient dermatology samples were also FSSC 2, with type 2-d again predominating. In contrast, environmental isolates from water sources were mostly Fusarium oxysporum species complex (FOSC) and those from air samples mostly Fusarium incarnatum-equiseti species complex (FIESC). A third of the environmental samples were FSSC, with species types FSSC 1-a and FSSC 1-b predominating.

Conclusions

Fusarium isolate species types from hematology patient infections were highly similar to those recovered from dermatology patients in the community. Four species types (FSSC 1-a, 1-b, 2-d and 2-f) were shared between hematology patients and the environment. Limitations in environmental sampling do not allow for nosocomial sources of infection to be ruled out. Future studies will focus on environmental factors that may have influenced the prevalence of FSSC fusariosis in this hematology ward.

A prospective randomized trial to reduce oral Candida spp. colonization in patients with hyposalivation

Low salivary flow rates are associated with higher oral Candida spp. counts, which may predispose to oral candidiasis. The aim of this study was to compare the effect of stimulating salivary flow rates with that of a regimen of chlorhexidine mouth rinse on the intensity of Candida colonization in patients with reduced salivary flow rates. Thirty-one outpatients were randomized to stimulate salivary output (group 1) or to receive chlorhexidine mouth rinses (group 2). Evaluations were performed at baseline (T0), at end of treatment (T1), and 15 days after last day of treatment (T2). Chewing-stimulated whole saliva samples were collected at each visit. Group 1 showed a constant reduction in median cfu counts, although the difference was significant only between T0 and T2 (p = 0.004). Group 2 showed a reduction in median Candida cfu counts between T0 and T1 (p = 0.01), but the counts increased at T2 (p = 0.01), and the difference between T0 and T2 was not significant (p = 0.8). In conclusion, patients who received salivary stimulation showed reductions of Candida cfu counts in saliva and a trend for increasing salivary flow rates between baseline and end of study evaluations. The use of chlorhexidine mouth rinses dramatically reduced Candida cfu counts, but when patients discontinued treatment, intensity of colonization rose again.

Subcutaneous phaeohyphomycosis caused by Cladophialophora sp.: a case report

A case of subcutaneous phaeohyphomycosis caused by Cladophialophora sp. is reported. The patient, an immunosuppressed host presented a nodule on the dorsum of the right hand which relapsed four months after excision. Dematiaceous septate hyphal and yeast like elements were seen in mycological and histological examination. The isolated fungus was identified on the basis of micro-macromorphological and physiologic characteristics.

Nosocomial outbreak of Exophiala jeanselmei fungemia associated with contamination of hospital water

From December 1996 through September 1997, we diagnosed 19 cases of fungemia due to Exophiala jeanselmei. We conducted a matched case-control study in which we cultured specimens of blood products, intravenous solutions, and water from a hospital water system. Isolates from environmental cultures were compared to those recovered from patients by random amplification of polymorphic DNA (RAPD). Multivariate analysis showed that neutropenia, longer duration of hospitalization, and use of corticosteroids were risk factors for infection. Environmental cultures yielded E. jeanselmei from 3 of 85 sources: deionized water from the hospital pharmacy, 1 water tank, and water from a sink in a non-patient care area. Use of deionized pharmacy water to prepare antiseptic solutions was discontinued, and no additional cases of infection occurred. RAPD typing showed that isolates from case patients and isolates from the pharmacy water were highly related, whereas the patterns of isolates recovered from the 2 other sources of water were distinct.

Relationship between salivary flow rates and Candida counts in subjects with xerostomia

OBJECTIVE

This study evaluated the relationship between salivary flow and Candida colony counts in the saliva of patients with xerostomia.

STUDY DESIGN

Sialometry and Candida colony-forming unit (CFU) counts were taken from 112 subjects who reported xerostomia in a questionnaire. Chewing-stimulated whole saliva was collected and streaked in Candida plates and counted in 72 hours. Species identification was accomplished under standard methods.

RESULTS

There was a significant inverse relationship between salivary flow and Candida CFU counts (P =.007) when subjects with high colony counts were analyzed (cutoff point of 400 or greater CFU/mL). In addition, the median sialometry of men was significantly greater than that of women (P =.003), even after controlling for confounding variables like underlying disease and medications. Sjögren's syndrome was associated with low salivary flow rate (P =.007). There was no relationship between the median Candida CFU counts and gender or age. There was a high frequency (28%) of mixed colonization. Candida albicans was the most frequent species, followed by C parapsilosis, C tropicalis, and C krusei.

CONCLUSIONS

In subjects with high Candida CFU counts there was an inverse relationship between salivary flow and Candida CFU counts.

Dermatophytoses in children: study of 137 cases

Dermatophytoses are common fungal infections caused by dermatophytes but there are few data about this condition in the childhood. 137 children below the age of 12 and clinically diagnosed as tineas were investigated prospectively at Instituto de Puericultura e Pediatria, Rio de Janeiro, from 1994 to 1999. Hair, skin/nails scraping and pus swabs were collected from lesions and processed for fungus. Male children from 2 to 12 years were mostly affected; tinea capitis (78 cases) mainly caused by Microsporum canis (46 cases) was the most common clinical form. Tinea corporis (43 cases) mainly caused by Trichophyton rubrum (17 cases) accounted for the second most frequent clinical form. Tinea cruris (10 cases) with Trichophyton rubrum (5 cases) as the most common etiologic agent accounted for the third most frequent clinical form. Tinea pedis and tinea unguium were much less frequent (3 cases each). Trichophyton rubrum was the most common etiologic agent isolated in these cases (3 cases).

Nosocomial fungemia due to Exophiala jeanselmei var. jeanselmei and a Rhinocladiella species: newly described causes of bloodstream infection

Fungi have become increasingly important causes of nosocomial bloodstream infections. The major cause of nosocomial fungemia has been Candida spp, but increasingly molds and other yeasts have caused disease. Exophiala jeanselmei and members of the genus Rhinocladiella are dematiaceous moulds, which have been infrequently associated with systemic infection and have not been described as causes of fungemia. In this paper, the occurrence of 23 cases of fungemia due to these organisms over a 10-month period is reported and the clinical characteristics of patients and outcomes are described. The majority of patients were immunosuppressed; 21 of 23 (91%) had received blood products and 78% had a central venous catheter. All patients had at least one manifestation of fever, but only one patient had signs or symptoms suggesting deep-seated infection. Antifungal therapy was given to 19 of the 23 patients; of those who did not receive therapy, 3 died prior to the culture result and 1 had been discharged without therapy. Antifungal susceptibility of the organisms showed activity of amphotericin B, itraconazole, and the new triazole antifungals voriconazole and posaconazole. E. jeanselmei and Rhinocladiella species are potential causes of nosocomial fungemia and may be associated with systemic infection.

Mixed infection caused by two species of Fusarium in a human immunodeficiency virus-positive patient

We report on a case of mixed infection caused by two species of Fusarium in a human immunodeficiency virus-positive patient with lymphoma who was neutropenic due to chemotherapy. The patient showed the typical signs of a disseminated fusarial infection, with Fusarium solani isolated from skin lesions and F. verticillioides isolated from blood. The report discusses how difficult it is to make an accurate diagnosis when an immunosuppressed patient is infected with more than one fungal species, especially when the species are morphologically very similar.

A double-blind, randomized, placebo-controlled trial of itraconazole capsules as antifungal prophylaxis for neutropenic patients

To evaluate the efficacy of itraconazole capsules in prophylaxis for fungal infections in neutropenic patients, we conducted a prospective, double-blind, placebo-controlled, randomized trial. Patients with hematologic malignancies or those who received autologous bone marrow transplants were assigned either a regimen of itraconazole (100 mg orally twice daily; n=104) or of placebo (n=106). Overall, fungal infections (superficial or systemic) occurred more frequently in the placebo group (15% vs. 6%; P=.03). There were no differences in the empirical use of amphotericin B or systemic fungal infections. Among patients with neutropenia that was profound (<100 neutrophils/mm3) and prolonged (for at least 7 days), those receiving itraconazole used less empirical amphotericin B (22% vs. 61%; P=.0001) and developed fewer systemic fungal infections (6% vs. 19%; P=.04). For patients with profound and prolonged neutropenia, itraconazole capsules at the dosage of 100 mg every 12 h reduce the frequency of systemic fungal infections and the use of empirical amphotericin B.

Fungemia due to Fusarium sacchari in an immunosuppressed patient

The fungus Fusarium sacchari was isolated repeatedly from the blood of an immunosuppressed host. The infection was treated successfully with a small dose of amphotericin B. The strain was resistant to this antifungal in vitro. MICs and minimum fungicidal concentrations of six antifungals for the clinical isolate are provided. To our knowledge, this is the first report involving this fungus in a case of fungemia.

Mycotic keratitis due to Curvularia senegalensis and in vitro antifungal susceptibilities of Curvularia spp

A case of mycotic keratitis due to Curvularia senegalensis is reported. This case represents the third known reported infection caused by this rare species. Fungal hyphae were detected in corneal scrapings, and repeated cultures were positive for this fungi. The patient was presumed cured after a corneal transplant and treatment with itraconazole, but the infection recurred and the patient is waiting for a keratoplasty. The in vitro antifungal susceptibilities of the case strain and another 24 strains belonging to seven species of Curvularia were tested for six antifungal agents. With the exception of flucytosine, and occasionally fluconazole, the other drugs assayed (amphotericin B, miconazole, itraconazole, and ketoconazole) were highly effective in vitro.

Predictive value of a positive nasal swab for Aspergillus sp. in the diagnosis of invasive aspergillosis in adult neutropenic cancer patients

To evaluate the value of a positive nasal swab for Aspergillus in the diagnosis of invasive aspergillosis, we prospectively evaluated nasal colonization in 173 episodes of neutropenia in 92 patients with hematological malignancies. Weekly nasal swabs were taken, and the patients were followed until death or resolution of neutropenia. The outcome variables were the development of invasive aspergillosis, empirical antifungal therapy and death. In 31 episodes of neutropenia (18%) there was at least one positive nasal swab for Aspergillus sp. Only two patients developed invasive aspergillosis, both with a positive nasal swab (p = 0.03). The positive and negative predictive values of a nasal swab were 6.4% and 100%, respectively. There was no difference between patients with positive or negative swabs regarding antifungal therapy or death. In this population of patients, a nasal swab for Aspergillus sp. had a low positive predictive value and a high negative predictive value for invasive aspergillosis.

Phialemonium fungemia: two documented nosocomial cases

Two fungal isolates recovered from the blood of two immunosuppressed patients are described as Phialemonium curvatum. One patient died, while the other, who was infected with Exophiala jeanselmei at the same time, survived after successful treatment with itraconazole. Analysis of internal transcribed spacer sequences demonstrated that the isolates belonged to the same strain and that the source of infection was probably a catheter. The taxonomic position of P. curvatum is discussed, and Phialemonium dimorphosporum is considered a synonym. The in vitro inhibitory activities of six antifungal agents (amphotericin B, itraconazole, ketaconazole, miconazole, flucytosine, and fluconazole) were determined against seven isolates of Phialemonium. Except for flucytosine, all of them were remarkably effective. Phialemonium should be added to the list of potential causes of nosocomial fungemia in cancer patients.

Risk factors for death among cancer patients with fungemia

In order to identify prognostic factors for death among cancer patients with fungemia, an 18-month survey of fungemia in patients with cancer was undertaken in three hospitals in Rio de Janeiro. For the assessment of risk factors for death, the following variables were analyzed: age; gender; underlying cancer; last treatment for the underlying disease; previous surgery; use of antibiotics, antifungal agents, steroids, or total parenteral nutrition; use of a central venous catheter; chemotherapy; radiotherapy; presence and duration of neutropenia; etiologic agent of the fungemia; treatment of the fungemia; clinical manifestations; and performance status (Karnofsky score) on the day of the positive blood culture. In multivariate analysis, the variables associated with an increased risk for death were older age, persistent neutropenia, and low performance status. Identifying risk factors for death may help to define a group-risk patients for whom new therapeutic options should be tried.