Evolution of antibody response and fungal antigens in the serum of a patient infected with Candida famata

Advances in Candida detection platforms for clinical and point-of-care applications

Invasive candidiasis remains one of the most serious community and healthcare-acquired infections worldwide. Conventional Candida detection methods based on blood and plate culture are time-consuming and require at least 2-4 days to identify various Candida species. Despite considerable advances for candidiasis detection, the development of simple, compact and portable point-of-care diagnostics for rapid and precise testing that automatically performs cell lysis, nucleic acid extraction, purification and detection still remains a challenge. Here, we systematically review most prominent conventional and nonconventional techniques for the detection of various Candida species, including Candida staining, blood culture, serological testing and nucleic acid-based analysis. We also discuss the most advanced lab on a chip devices for candida detection.

Fungal infection in cerebrospinal fluid from some patients with multiple sclerosis

Multiple sclerosis (MS) is the prototypical inflammatory disease of the central nervous system and spinal cord, leading to axonal demyelination of neurons. Recently, we have found a correlation between fungal infection and MS in peripheral blood of patients. The present work provides evidence of fungal infection in the cerebrospinal fluid (CSF) of some MS patients. Thus, fungal antigens can be demonstrated in CSF, as well as antibodies reacting against several Candida species. Comparison was made between CSF and blood serum for the presence of fungal antigens (proteins) and antibodies against different Candida spp. Analyses of both CSF and serum are complementary and serve to better evaluate for the presence of disseminated fungal infection. In addition, PCR analyses indicate the presence of DNA from different fungal species in CSF, depending on the patient analyzed. Overall, these findings support the notion that fungal infection can be demonstrated in CSF from some MS patients. This may constitute a risk factor in this disease and could also help in understanding the pathogenesis of MS.

Fungal infection in a patient with multiple sclerosis

Multiple sclerosis (MS) is a chronic, inflammatory disease of the central nervous system, whose causes are still unknown. We have proposed that MS, as well as some ophthalmologic diseases, are associated with fungal infection. In the present study, we closely monitored a patient with MS over a three-year period. Antibodies against different Candida spp. were detected in peripheral blood serum, although the titer of these antibodies fluctuated. The presence of fungal macromolecules, such as proteins, polysaccharides, and DNA, was also tested. In several sera samples, antigens related to C. famata were evidenced by the slot-blot test using a rabbit polyclonal antibody against these species, while high levels of β-1,3 glucan were detected with the commercial Fungitell assay. Despite the variations by sample, we concluded that all fungal macromolecules, that is, proteins, polysaccharides, and DNA, were present in blood from the MS patient which was analyzed. Several fungal species were identified using polymerase chain reaction (PCR) followed by sequencing. Antibodies against Candida spp. as well as C. famata-related antigens were also detected in cerebrospinal fluid (CSF). Our findings provide support for the notion that disseminated mycosis is present in this patient.

Association between multiple sclerosis and Candida species: evidence from a case-control study

Candida infection among multiple sclerosis (MS) patients has not been studied in depth. We determined whether there is an association between serological evidence of Candida infection and MS. Blood specimens were obtained from 80 MS patients and 240 matched controls. Immunofluorescence analysis and ELISA were used to detect Candida species antibodies and slot-blot to detect antigens. Using immunofluorescence analysis, moderate to high concentrations of serum antibodies to Candida famata were present in 30 (37.5%) MS patients vs. 30 (12.5%) controls (p < 0.001). Results for Candida albicans were 47.5% (38/80) in MS patients vs. 21.3% (51/240) in controls (p < 0.001), for Candida parapsilosis 37% (28/80) vs. 17.1% (41/240) (p < 0.001) and for Candida glabrata 46.3% (37/80) vs. 17.5% (42/240) (p < 0.001), respectively. After adjusting for age and gender, the odds ratios (95% confidence intervals) for MS, according to the presence of Candida antigens were: 2.8 (0.3-23.1, p = 0.337) for Candida famata; 1.5 (0.7-3.4, p = 0.290) for Candida albicans; 7.3 (3.2-16.6, p < 0.001) for Candida parapsilosis; and 3.0 (1.5-6.1, p = 0.002) for Candida glabrata. The results were similar after excluding ten patients on immunosuppressants. The results of this single study suggest that Candida species infection may be associated with increased odds of MS.

Differentiation of Debaryomyces hansenii and Candida famata by rRNA gene intergenic spacer fingerprinting and reassessment of phylogenetic relationships among D. hansenii, C. famata, D. fabryi, C. flareri (=D. subglobosus) and D. prosopidis: description of D. vietnamensis sp. nov. closely related to D. nepalensis

The intergenic spacer rDNA amplification and AluI fingerprinting (IGSAF) method detected four distinct groups among 170 Debaryomyces hansenii strains: D. hansenii var. hansenii; Candida famata var. famata; D. hansenii var. fabryi and C. famata var. flareri. IGS sequence comparison of representative strains showed that D. hansenii var. hansenii and C. famata var. famata belonged to one species, whereas D. hansenii var. fabryi and C. famata var. flareri belonged to two different ones. This confirmed the following three species recently reinstated: D. hansenii (=C. famata), Debaryomyces fabryi and Debaryomyces subglobosus (=Candida flareri). Accordingly, growth at 37 degrees C may no longer be used to differentiate D. hansenii from D. fabryi. Riboflavin production is more specific for D. fabryi and D. subglobosus strains. IGSAF identified all the other 17 species of the genus Debaryomyces, six of them sharing with D. hansenii an rRNA gene unit harbouring two 5S rRNA genes. The phylogenetic tree established with IGS sequences was congruent with the one based on ACT1, GPD1 and COX2 sequences depicting a distinct D. hansenii clade close to the D. subglobosus, Debaryomyces prosopidis and D. fabryi clade. Description of Debaryomyces vietnamensis sp. nov. (type strain CBS 10535(T), MUCL 51648(T)), closely related to Debaryomyces nepalensis is given.

Fungal infection in patients with serpiginous choroiditis or acute zonal occult outer retinopathy

The etiologies of a number of retinopathies, including serpiginous choroiditis and acute zonal occult outer retinopathy (AZOOR), remain uncertain. Recently, we provided evidence that AZOOR is caused by Candida famata infection. The purpose of this article was to investigate the presence of fungal infection in five patients affected with serpiginous choroiditis and five patients with diagnosis of AZOOR. To assess the presence of fungal infection the presence of antibodies in human serum samples against C. famata, C. albicans, C. parapsilosis, C. glabrata and C. krusei was analyzed. In addition, quantitative PCR was carried out to detect fungal genomes in whole blood. Finally, the presence of fungal antigens in the serum samples of patients was investigated. Three AZOOR patients presented high antibody titers against Candida spp., while antibodies against Candida spp. were observed in serum samples from four patients with serpiginous choroiditis. Fungal genomes in peripheral blood were evidenced in serum samples from one AZOOR and four serpiginous choroiditis patients. Fungal antigens were also apparent in the serum of different patients. Our findings indicate that there was evidence of disseminated fungal infection in most patients examined.