Successful treatment of refractory chronic disseminated candidiasis after prolonged administration of caspofungin in a child with acute myeloid leukemia

Diagnosing fungal infections in clinical practice: a narrative review

BACKGROUND

Invasive fungal infections (IFI) present a major medical challenge, with an estimated 6.5 million cases annually, resulting in 3.8 million deaths. Pathogens such as Aspergillus spp. Candida spp. Mucorales spp. Cryptococcus spp. and other fungi species contribute to these infections, posing risks to immunocompromised individuals. Early and accurate diagnosis is crucial for effective treatment and better patient outcomes.

AREAS COVERED

This narrative review provides an overview of the current methods and challenges associated with diagnosing fungal diseases, including invasive aspergillosis and invasive candidiasis, as well as rare and endemic fungal infections. Various diagnostic techniques, including microscopy, culture, molecular diagnostics, and serological tests, are reviewed, highlighting their respective advantages and limitations and role in clinical guidelines. To illustrate, the need for improved diagnostic strategies to overcome existing challenges, such as the low sensitivity and specificity of current tests and the time-consuming nature of traditional culture-based methods, is addressed.

EXPERT OPINION

Current advancements in fungal infection diagnostics have significant implications for healthcare outcomes. Improved strategies like molecular testing and antigen detection promise early detection of fungal pathogens, enhancing patient management. Challenges include global access to advanced technologies and the need for standardized, user-friendly point-of-care diagnostics to improve diagnosis of fungal infections globally.

Diagnostic Imaging and Invasive Fungal Diseases in Children

Invasive fungal disease (IFD) is a life-threatening condition, especially in immunocompromised children. The role of diagnostic imaging in children at risk for an IFD is multifactorial, including initially detecting it, evaluating for dissemination of infection beyond the primary site of disease, monitoring the response to antifungal therapy, and assessing for potential relapse. The objective of this review was to synthesize the published literature relevant to the use of various imaging modalities for the diagnosis and management of IFD in children.

Chronic disseminated candidiasis complicated with a ruptured intracranial fungal aneurysm in ALL

An 11-year-old boy with acute lymphocytic leukemia (ALL) contracted disseminated candidiasis during induction therapy, which was complicated with rupture of a fungal cranial aneurysm. Ventricular drainage and coil embolization of a residual aneurysm in combination with intensive antifungal therapy rescued the patient. Although clinical improvement was achieved, high fever and elevated levels of C-reactive protein and β-D-glucan continued for more than 10 mo. One year later, the ALL relapsed during maintenance therapy with methotrexate and 6-mercaptopurine. After salvage chemotherapy, the patient received unrelated bone marrow transplantation (BMT) in a non-complete remission condition and survived. During subsequent chemotherapy and BMT, no recurrence of the fungal infection was observed under the prophylactic anti-fungal therapy with micafungin.

Multilaboratory testing of two-drug combinations of antifungals against Candida albicans, Candida glabrata, and Candida parapsilosis

There are few multilaboratory studies of antifungal combination testing to suggest a format for use in clinical laboratories. In the present study, eight laboratories tested quality control (QC) strain Candida parapsilosis ATCC 22019 and clinical isolates Candida albicans 20533.043, C. albicans 20464.007, Candida glabrata 20205.075, and C. parapsilosis 20580.070. The clinical isolates had relatively high azole and echinocandin MICs. A modified CLSI M27-A3 protocol was used, with 96-well custom-made plates containing checkerboard pairwise combinations of amphotericin B (AMB), anidulafungin (AND), caspofungin (CSP), micafungin (MCF), posaconazole (PSC), and voriconazole (VRC). The endpoints were scored visually and on a spectrophotometer or enzyme-linked immunosorbent assay (ELISA) reader for 50% growth reduction (50% inhibitory concentration [IC(50)]). Combination IC(50)s were used to calculate summation fractional inhibitory concentration indices (FICIs) (ΣFIC) based on the Lowe additivity formula. The results revealed that the IC(50)s of all drug combinations were lower or equal to the IC(50) of individual drugs in the combination. A majority of the ΣFIC values were indifferent (ΣFIC = 0.51 to 2.0), but no antagonism was observed (ΣFIC ≥ 4). Synergistic combinations (ΣFIC ≤ 0.5) were found for AMB-PSC against C. glabrata and for AMB-AND and AMB-CSP against C. parapsilosis by both visual and spectrophotometric readings. Additional synergistic interactions were revealed by either of the two endpoints for AMB-AND, AMB-CSP, AMB-MCF, AMB-PSC, AMB-VRC, AND-PSC, CSP-MCF, and CSP-PSC. The percent agreements among participating laboratories ranged from 37.5% (lowest) for AND-CSP and POS-VOR to 87.5% (highest) for AMB-MCF and AND-CSP. Median ΣFIC values showed a wide dispersion, and interlaboratory agreements were less than 85% in most instances. Additional studies are needed to improve the interlaboratory reproducibility of antifungal combination testing.

Nebulized liposomal amphotericin B and combined systemic antifungal therapy for the treatment of severe pulmonary aspergillosis after allogeneic hematopoietic stem cell transplant for a fatal mitochondrial disorder

Nebulized liposomal amphotericin B (20-15 mg twice daily by nebulizer) was combined with high dose intravenous liposomal amphotericin B (10 mg/kg/day) and high dose caspofungin (100 mg/m(2)) for the treatment of severe, recurrent pulmonary aspergillosis following allogeneic hematopoietic stem cell transplantation from alternative donor in a patient with mitochondrial disease (Pearson's syndrome). This combined treatment was administered for 8 days. Nebulized liposomal amphotericin B was well tolerated. Since severe transplant complications developed, nebulized administration was withdrawn and intravenous doses of liposomal amphotericin B and caspofungin were tapered to usual schedules. Pulmonary aspergillosis responded well to 45 days of combined intravenous antifungal therapies which were maintained for 2 years with secondary prophylaxis, because of persistent immunosuppressive treatment.