Detection of fungi in sinus fluid of patients with allergic fungal rhinosinusitis

Allergic Fungal Rhinosinusitis in Saudi Arabia: A Review of Recent Literature

Allergic fungal rhinosinusitis (AFRS) has been considered an enigma since it was first described four decades ago. Previous research has found that AFRS has multiple definitions and a poorly understood pathogenesis because it overlaps with other conditions and necessitates meticulous work and multiple diagnostic modalities to confirm the diagnosis. However, despite the expansion of medical and surgical treatments, recurrence still occurs. In this review, the recent literature on AFRS cases in Saudi Arabia with relevance to its epidemiology, diagnosis, and management was studied and compared with international data. PubMed, Google Scholar, and Cochrane Library were searched for original research and review articles with local data. There is an evident paucity and contradiction between local studies regarding the epidemiology, diagnostic methods, and management of AFRS. Hence, well-defined randomized controlled trials (RCTs) are needed for the treatment of this chronic recurrent disease.

Etiology of Chronic Rhinosinusitis: The Role of Fungus

Chronic rhinosinusitis (CRS) is a multifactorial disease. Predisposing factors can be divided into environmental and non-host factors, such as pollution, viral infections, smoking, fungus, and bacteria; general host factors, including genetic factors and immune deficiency; and local host factors, including persistent focal inflammation within the ostiomeatal complex. Evidence suggests that the underlying bone in the ostiomeatal complex is actively involved in the disease process of CRS. The evidence concerning a broad range of predisposing factors for CRS is reviewed. Chronic rhinosinusitis is an inflammatory disorder with numerous predisposing factors, including genetics, pollution, anatomic anomalies, bacteria, and fungus. In some studies, fungi have been cultured from nearly 100% of patients with rhinosinusitis and nasal polyposis. T-cell sensitization to fungus with production of the T-helper 2 (Th2) cytokine interleukin-5 has been proposed as a key step in the initiation of the disease. Interleukin-5 also plays an important role in the effector phase of the disease through its effects on eosinophilopoesis and eosinophil survival. There is considerable controversy concerning the role of fungi as the cause of “chronic eosinophilic rhinosinusitis” and whether this even represents a distinct clinical entity. Further study is also required to define the optimal treatment for the disease.

Immunodetection of fungal and oomycete pathogens: established and emerging threats to human health, animal welfare and global food security

Filamentous fungi (moulds), yeast-like fungi, and oomycetes cause life-threatening infections of humans and animals and are a major constraint to global food security, constituting a significant economic burden to both agriculture and medicine. As well as causing localized or systemic infections, certain species are potent producers of allergens and toxins that exacerbate respiratory diseases or cause cancer and organ damage. We review the pathogenic and toxigenic organisms that are etiologic agents of both animal and plant diseases or that have recently emerged as serious pathogens of immunocompromised individuals. The use of hybridoma and phage display technologies and their success in generating monoclonal antibodies for the detection and control of fungal and oomycete pathogens are explored. Monoclonal antibodies hold enormous potential for the development of rapid and specific tests for the diagnosis of human mycoses, however, unlike plant pathology, their use in medical mycology remains to be fully exploited.

Investigation of fungi in massive nasal polyps: microscopy, culture, polymerase-chain reaction, and serology

BACKGROUND

Although some clues exist about the causative relationship of fungi and chronic rhinosinusitis, the relationship of nasal polyps and fungi has not been enlightened. The purpose of this study was to determine whether a relationship exists between fungi and massive nasal polyps and to evaluate current available diagnostic techniques for detection of fungi.

METHODS

Thirty cases of massive nasal polyposis (NP) were evaluated prospectively for fungal evidence and were compared with 18 cases of concha bullosa based on direct microscopy, fungal culture, serology, polymerase chain reaction (PCR), and sequencing.

RESULTS

Fungal colonization was detected in 15 (50.0%) of the cases with massive NP, but only in 2 (11.1%) of the cases with concha bullosa. A significant difference was found between the study and the control groups in terms of fungal existence (p < 0.016). Direct microscopy was positive in 14 (46.7%) and 1 (5.6%) of the cases;fungal culture was positive in 8 (26.7%) and 4 (22.2%) of the cases; serology was positive in 9 (30.0%) and 2 (11.1%) of the cases; PCR was positive in 18 (60.0%) and 6 (33.3%) of the cases with massive NP and concha bullosa, respectively.

CONCLUSION

Fungal colonization was found to be more common in massive NP patients compared with the control group. According to our results, microscopy and PCR were most sensitive techniques for detection of fungi.

Dental implant-assisted prosthetic rehabilitation of a patient with a bilateral maxillectomy defect secondary to mucormycosis

Prosthodontic rehabilitation of patients with bimaxillary resection involving the maxillae, hard and soft palates, and paranasal sinuses presents a significant challenge in restoring speech, deglutition, mastication, and respiration. This clinical report describes the prosthodontic management of a young girl treated for leukemia who required a bilateral maxillectomy secondary to mucormycosis. Distraction osteogenesis, bone grafts, osseointegrated implants, and magnet attachments were used to provide retention, support, and stability of a large definitive obturator.

Etest for assessing the susceptibility of filamentous fungi

The purpose of this study was to evaluate the Etest as an in vitro antifungal susceptibility test method for different moulds originating from human samples and from the environment. A total of 50 isolates (1 Acremonium, 18 Aspergillus, 2 Cladosporium, 1 Epicoccum, 15 Penicillium, 2 Scopulariopsis and 11 Trichoderma strains) were tested by the Etest. Forty-six of the tested moulds (92%) were resistant to fluconazole with minimal inhibitory concentrations (MICs) > or = 256 microg ml(-1). There were strains resistant to ketoconazole among Aspergillus niger, A. ochraceus and Cladosporium spp. with MICs > 32 microg ml(-1). For fluconazole, no differences were observed using two different inocula, while for itraconazole, ketoconazole and amphotericin B, a 1 or less step 2-fold dilution difference in MIC was seen for the most of 10 selected strains. The MICs of fluconazole and amphotericin B obtained for Trichoderma strains by the Etest and the agar dilution method were also compared. MICs for fluconazole were in agreement, while MICs for amphotericin B were higher with 1 or 2 steps of 2-fold dilutions for most of Trichoderma strains in the case of the agar dilution method.

Allergic fungal sinusitis: diagnosis and treatment

Since allergic fungal sinusitis was initially described by Millar in 1981, many have tried to define and explain the disorder. It has been labeled as the sinonasal equivalent of allergic bronchopulmonary aspergillosis; however, allergic fungal sinusitis cannot be categorized so easily. According to the literature at this time, there are five major criteria and six associated characteristics or minor criteria of patients with allergic fungal sinusitis. In reality, patients may not develop all five major criteria or have any of the associated criteria for years. Allergic fungal sinusitis is not only difficult to diagnose, but it is one of the most complicated conditions rhinologists must manage. Endoscopic sinus surgery must be used in conjunction with long-term medical therapy, oral and nasal corticosteroids, immunotherapy, antifungal therapy, and antimicrobial agents to effectively control the problem. Allergic fungal sinusitis is most likely the endpoint in a spectrum of sinonasal disease, driven by the presence of fungus and eosinophils with their inflammatory mediators. The affected nasal mucosa no longer functions properly, and a cycle of chronic edema, stasis, and bacterial superinfection results. Therapy entails disrupting the inflammatory process to allow normal mucosal function to resume.

Identification and incidence of fungal strains in chronic rhinosinusitis patients

The fungal revolution taking place in otorhinology inspired us to study the frequency of occurrence of fungi in the nasal mucus of chronic rhinosinusitis (CRS) patients (with or without polyposis) in order to evaluate the incidence of eosinophilic fungal sinusitis in CRS patients. Ninety-six samples were examined from patients with CRS. In 74 cases mucus was collected non-invasively, and in 22 cases during operation. The Gram-stained direct smears of all samples were also evaluated. Bacteria and fungi colonizing in the mucus were detected by culturing method. The control group consisted of 50 healthy volunteers. Typical aerobic pathogenic bacteria could be isolated from 34 patients. Fifty-seven aerobic bacteria were isolated, i.e. 1.6 bacteria/positive patient with a maximum of 3 different bacteria/sample. The most frequently isolated bacteria were Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Streptococcus pneumoniae, and Haemophilus influenzae. Yeasts and moulds could be detected from 79 patients (83%): Candida albicans, Candida spp., Aspergillus spp., Cladosporium spp, and Penicillium spp. were isolated most frequently. Altogether 237 yeasts and moulds were isolated, i.e. 3.0 different fungi/positive patient, with a maximum of 5 different fungi/sample. In the control group aerobic pathogens were not isolated, only apathogenic species. Fungi were isolated from 22 healthy patients (44%). These data indicate that fungi are frequently involved in the aetiology of CRS. IgE-medicated hypersensitivity to fungal allergens could not be proven in our patients.

Speech sound representation, perception, and plasticity: a neurophysiologic perceptive

Historically, auditory research has focused predominately upon how relatively simple acoustic signals are represented in the neuronal responses of the auditory periphery. However, in order to understand the neurophysiology underlying speech perception, the ultimate objective is to discover how speech sounds are represented in the central auditory system and to relate that representation to the perception of speech as a meaningful acoustic signal. This paper reviews three areas that pertain to the central auditory representation of speech: (1) the differences in neural representation of speech sounds at different levels of the auditory system; (2) the relation between the representation of sound in the auditory pathway and the perception/misperception of speech, and (3) the training-related plasticity of speech sound neural representation and speech perception.