Atypical skin lesions caused by Curvularia sp. and Pseudallescheria boydii in two patients after allogeneic bone marrow transplantation

Experimental Phaeohyphomycosis of Curvularia lunata

Originally considered to be a plant pathogen, reports of phaeohyphomycosis due to Curvularia lunata (C. lunata) in animals and humans are increasing. However, studies on the pathogenesis, virulence, and epidemiology of C. lunata have rarely been discussed. In the present study, BALB/c mice were experimentally inoculated with C. lunata suspension by different routes and the course of infection was evaluated. In addition, the in vitro antifungal susceptibility of C. lunata against six commonly used antifungals was evaluated using the microdilution method. Inoculation resulted in skin lesions in animals inoculated intraperitonially and subcutaneously. Infection was confirmed by both mycological and histopathologic examination. C. lunata spores and hyphae were detected in the histopathologic sections stained with hexamine silver staining. In addition, voriconazole (VRC) demonstrated greater activity against C. lunata when compared to the other antifungals, whereas fluconazole (FLC) was the least active antifungal with a minimum inhibitory concentration (MIC) range of 8–16 μg/mL. Further studies are necessary to understand the pathogenicity of C. lunata and uncover the mystery of this fungus.

Strain Distribution and Drug Susceptibility of Invasive Fungal Infection in Clinical Patients With Systemic Internal Diseases

Background

Patients with systemic internal diseases present high risks for invasive fungal infections, which results in increased morbidity and mortality. Identification of high-risk departments and susceptibility systems could help to reduce the infective rate clinically. Correct selection of sensitive anti-fungal drugs not only could improve the cure rate but also could reduce the adverse reactions and complications caused by long-term antifungal drug treatment, which can be especially important in patients with serious systemic diseases. Therefore, the distribution changes of invasive fungal strains in patients with systemic internal diseases and the choice of antifungal drugs in clinical practice should be updated.

Objective

This work aimed to investigate the incidence, strain distributions, and drug susceptibility of invasive fungal strains isolated from patients with systemic internal diseases.

Methods

Samples were collected from 9,430 patients who were diagnosed with internal diseases in our hospital from January to December 2018. We then cultured and identified the fungal strains using API 20C AUX. We performed drug sensitivity analysis via the ATB Fungus-3 fungal susceptibility strip. Resistance was defined using the revised Clinical Laboratory Standardization Committee of United States breakpoints/epidemiological cutoff values to assign susceptibility or wild-type status to systemic antifungal agents.

Results

A total of 179 patients (49 female, 130 male) with fungal infection were included. The high-incidence departments were determined to be the respiratory department (34.64%), intensive care unit (ICU; 21.79%), and hepatology department (9.50%). The susceptible systems for infection were the respiratory tract (sputum, 68.72%, 123/179; secretion retained in the tracheal catheter, 3.35%, 6/179), urinary tract (urine, 9.50%, 17/179), and gastrointestinal tract (feces, 9.50%, 17/179). The major pathogens were Candida (90.50%), Aspergillus (8.93%), and Cryptococcus neoformans (0.56%). The infective candida subgroups were Candida albicans (70.95%), Candida krusei (6.15%), Candida glabrata (5.59%), Candida parapsilosis (3.91%), and Candida tropicalis (3.91%). The susceptibility of non-Aspergillus fungi for amphotericin B was 100.0%. The susceptibility rates of 5-fluorocytocine (5-FC) and voriconazole were 72.73 and 81.82%, respectively, for C. krusei, 98.43 and 100% for C. albicans, and 100% for both drugs for C. glabrata, C. parapsilosis, and C. tropicalis. The susceptibility rates of fluconazole and itraconazole were 0 and 54.55%, respectively, for C. krusei, 20 and 20% for C. glabrata, and 57.14 and 57.14% for C. tropicalis. The resistance rate of C. tropicalis for both fluconazole and itraconazole was 41.43%.

Conclusion

Patients in the respiratory department, ICU, and hepatology department presented high rates of invasive fungal infections and should include special attention during clinical treatment. The respiratory tract, urinary tract, and gastrointestinal tract were the susceptible systems. Candida, especially C. albicans, was the main pathogen. From the perspective of drug sensitivity, amphotericin B should be given priority in treating the non-Aspergillus fungi infection in patients with systemic internal diseases, while the susceptibility of invasive fungal strains to azoles was variant. These data might provide clinical evidence for the prevention and treatment of invasive fungal infection in patients with systemic internal diseases.

Black mold takes hold and story told

We present a case of an invasive Curvularia infection in a patient who developed following bilateral orthotopic lung transplantation despite receiving post-transplant antifungal prophylaxis. This infection presented as mold colonies studding the interior surface of his chest tubes. Despite surgical washout of his bilateral pleural cavities and antifungal treatment with liposomal amphotericin B, micafungin, and isavuconazonium sulfate, the patient died.

Invasive Scedosporium spp. and Lomentospora prolificans infections in pediatric patients: Analysis of 55 cases from FungiScope® and the literature

OBJECTIVES

Current knowledge on infections caused by Scedosporium spp. and Lomentospora prolificans in children is scarce. We therefore aim to provide an overview of risk groups, clinical manifestation and treatment strategies of these infections.

METHODS

Pediatric patients (age ≤18 years) with proven/probable Scedosporium spp. or L. prolificans infection were identified in PubMed and the FungiScope® registry. Data on diagnosis, treatment and outcome were collected.

RESULTS

Fifty-five children (median age 9 years [IQR: 5-14]) with invasive Scedosporium spp. (n = 33) or L. prolificans (n = 22) infection were identified between 1990 and 2019. Malignancy, trauma and near drowning were the most common risk factors. Infections were frequently disseminated. Most patients received systemic antifungal therapy, mainly voriconazole and amphotericin B, plus surgical treatment. Overall, day 42 mortality was 31%, higher for L. prolificans (50%) compared to Scedosporium spp. (18%). L. prolificans infection was associated with a shorter median survival time compared to Scedosporium spp. (6 days [IQR: 3-28] versus 61 days [IQR: 16-148]). Treatment for malignancy and severe disseminated infection were associated with particularly poor outcome (HR 8.33 [95% CI 1.35-51.40] and HR 6.12 [95% CI 1.52-24.66], respectively). Voriconazole use at any time and surgery for antifungal treatment were associated with improved clinical outcome (HR 0.33 [95% CI 0.11-0.99] and HR 0.09 [95% CI 0.02-0.40], respectively).

CONCLUSIONS

Scedosporium spp. and L. prolificans infections in children are associated with high mortality despite comprehensive antifungal therapy. Voriconazole usage and surgical intervention are associated with successful outcome.

Invasive Curvularia Infection in Pediatric Patients With Hematologic Malignancy Identified by Fungal Sequencing

Curvularia is a saprophytic dematiaceous mold and a rare human pathogen. Here, we report three severely immunocompromised pediatric patients who developed invasive Curvularia infection. Diagnosis was achieved or confirmed in all cases by fungal ribosome sequencing, which hastened species identification and targeted treatment for the patients reported. There are no treatment guidelines for invasive Curvularia infection, though we report three patients who were cured of their infection through a combination of surgical resection and various anti-fungal therapies, indicating a relatively low virulence and good prognosis in comparison to other angioinvasive molds.

Verrucous Onychomycosis Caused by Curvularia in a Patient with Congenital Pterygium

A 57 year healthy farmer with congenital nail pterygium presented with a verrucous growth on nail bed since 8 months. He was not diabetic and HIV rapid card test negative. Our clinical diagnosis was chromoblastomycosis but culture showed growth of curvularia species on two occasions and histopathology showed hyphal and yeast forms of the pigmented fungus. After excision biopsy patient was started on oral itraconazole. This case is reported due to rarity of verrucous cutaneous lesions caused by curvularia in immunocompetent individuals.

Thermotherapy in dermatologic infections

The use of local induced hyperthermia or thermotherapy for dermatologic infections has not been fully explored in the more recent medical literature. Herein, we discuss the rationale behind the use of thermotherapy and review reported clinical experience with its use in the management of cutaneous infections.

Infections caused by Scedosporium spp

Scedosporium spp. are increasingly recognized as causes of resistant life-threatening infections in immunocompromised patients. Scedosporium spp. also cause a wide spectrum of conditions, including mycetoma, saprobic involvement and colonization of the airways, sinopulmonary infections, extrapulmonary localized infections, and disseminated infections. Invasive scedosporium infections are also associated with central nervous infection following near-drowning accidents. The most common sites of infection are the lungs, sinuses, bones, joints, eyes, and brain. Scedosporium apiospermum and Scedosporium prolificans are the two principal medically important species of this genus. Pseudallescheria boydii, the teleomorph of S. apiospermum, is recognized by the presence of cleistothecia. Recent advances in molecular taxonomy have advanced the understanding of the genus Scedosporium and have demonstrated a wider range of species than heretofore recognized. Studies of the pathogenesis of and immune response to Scedosporium spp. underscore the importance of innate host defenses in protection against these organisms. Microbiological diagnosis of Scedosporium spp. currently depends upon culture and morphological characterization. Molecular tools for clinical microbiological detection of Scedosporium spp. are currently investigational. Infections caused by S. apiospermum and P. boydii in patients and animals may respond to antifungal triazoles. By comparison, infections caused by S. prolificans seldom respond to medical therapy alone. Surgery and reversal of immunosuppression may be the only effective therapeutic options for infections caused by S. prolificans.

[Case of cutaneous Pseudallescheria boydii infection caused by trauma]

Pseudallescheria boydii is a ubiquitous filamentous fungus. We report a case of cutaneous P. boydii infection of the left knee in a 79-year-old Japanese man who was receiving oral predonisolone (25 mg/day) for radiation pneumonitis after radiation therapy on left breast cancer. He presented with a 2-week-history of a lesion on the left knee. A biopsy specimen from the skin lesion revealed granulomatous inflammation with hyphae. Culture of the pus from the skin specimen confirmed the diagnosis of cutaneous P. boydii infection. rDNA ITS sequence was analyzed to confirm the mycological diagnosis. The patient was treated orally with 200 mg/day of itraconazole. The lesion was gradually cured and left a hypertrophic scar. Cutaneous injury may be responsible for an incidence of localized infection. Such rare fungus infection in immunocompromised patients who have a persistent traumatic skin ulcer needs to be ruled out. An opportunistic infection in immunocompromised patients can be life-threatening and prompt treatment based on accurate diagnosis is important.

Cutaneous Scedosporium apiospermum Infection in an Immunocompromised Patient and a Review of the Literature

Scedosporium apiospermum (also known as Pseudallescheria boydii) is a ubiquitous filamentous fungus. This fungus is known as a cause of mycetoma, which may occur in a normally immune host following trauma. However, in an immunocompromised host, S. apiospermum may cause a life-threatening infection. We describe a case of S. apiospermum infection of the right hand in a patient who was receiving long-term immunosuppressants for adult Still's disease. We also review the cases of S. apiospermum infection with cutaneous manifestations reported between 1998 and 2003.

Infections Due to Scedosporium apiospermum and Scedosporium prolificans in Transplant Recipients: Clinical Characteristics and Impact of Antifungal Agent Therapy on Outcome

BACKGROUND

Unique characteristics, impact of therapy with antifungal agents, and outcome of infections with Scedosporium species were assessed in transplant recipients.

METHODS

The patients comprised a total of 80 transplant recipients with Scedosporium infections, including 13 patients from our institutions (University of Pittsburgh Medical Center [Pittsburgh, PA], University of Maryland [Baltimore], Duke University Medical Center [Durham, NC], Emory University [Atlanta, GA], and Hospital Gregorio Maranon [Madrid, Spain]) and 67 reported in the literature. The transplant recipients were compared with 190 non-transplant recipients with scedosporiosis who were described in the literature.

RESULTS

Overall, 69% of the infections in hematopoietic stem cell transplant (HSCT) recipients and 53% of the infections in organ transplant recipients were disseminated. HSCT recipients, compared with organ transplant recipients, were more likely to have infections caused by Scedosporium prolificans (P=.045), to have an earlier onset of infection (P=.007), to be neutropenic (P<.0001), and to have fungemia (P=.04). Time elapsed from transplantation to Scedosporium infection in transplant recipients has increased in recent years (P=.002). The mortality rate among transplant recipients with scedosporiosis was 58%. In a logistic regression model using amphotericin B as comparison treatment, voriconazole was associated with a trend towards better survival (odds ratio [OR], 10.40; P=.08). Presence of disseminated infection (OR, 0.20; P=.03) predicted lower survival, and receipt of adjunctive surgery as treatment (OR, 5.52; P=.02) independently predicted a better survival in this model.

CONCLUSIONS

Scedosporium infections in transplant recipients were associated with a high rate of dissemination and a poor outcome overall. The use of newer triazole agents warrants consideration as a therapeutic modality for these infections.

Nonpseudomonal ecthyma gangrenosum

Ecthyma gangrenosum is a cutaneous infection associated most commonly with pseudomonal sepsis in the patient who is immunocompromised. We describe an 8-month-old girl with acute myelocytic leukemia who developed perineal ecthyma gangrenosum caused by Citrobacter freundii, a gram-negative pathogen that has been rarely associated with cutaneous disease. We also review the literature to categorize the range of pseudomonal and nonpseudomonal pathogens associated with ecthyma gangrenosum.

Curvularia—favorable response to oral itraconazole therapy in two patients with locally invasive phaeohyphomycosis

Curvularia species are ubiquitous and occasionally lead to infections in humans. In immunosuppressed patients, infections are often serious, and systemic dissemination is not uncommon. The optimal antifungal therapy is unclear. I here present two cases, a healthy man with locally invasive, mulicentric paranasal fungal sinusitis, and a case of progressive verrucal distal onychomycosis that developed while the patient was undergoing accelerated chemotherapy for non-Hodgkin's lymphoma. Both patients showed excellent responses to treatment with itraconazole suspension. Oral itraconazole may provide a safe and effective alternative for patients with locally invasive non-disseminated mycoses due to Curvularia species.

Lethal systemic dissemination from a cutaneous infection due to Curvularia lunata in a heart transplant recipient

A 69-year-old male heart transplant recipient, being treated with Cell Cept, FK 506 and methylprednisolone had multiple deep brown skin nodules and nodes, on the upper right arm. Skin biopsy and culture detected a strain of Curvularia lunata. The infection disseminated to the whole skin surface, oral mucosa, upper third of the oesophagus and to the lungs. Therapy with antibiotics and antifungal drugs was ineffective. The patient died of sepsis. We did not find any other case of systemic dissemination from a skin infection due to C. lunata among heart transplant recipients. We feel that heart transplant recipients need adequate education to prevent situations that would put them at risk for infection and to seek medical advice immediately for an early diagnosis and an effective therapy.