Browsing by Author "Marques Lito, Luis"
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- Isolation of Rasamsonia argillacea species complex in a Cystic Fibrosis Adult Patient - First Case in PortugalPublication . Carvalho, Dinah; Sabino, Raquel; Veríssimo, Cristina; Simões, Helena; Azevedo, Pilar; Marques Lito, Luis; Melo Cristino, JoséObjectives: Cystic fibrosis (CF) is the most common monogenetic autosomal reces sive disease in the human population. An important fungal biota has been described in respiratory secretions of patients suffering from CF being Aspergillus fumigatus and Candida albicans the most common fungi found. We report the isolation, for the first time in Portugal, of the emerging fungal pathogen Rasamsonia argillacea species complex, from a respiratory sample of an adult patient with CF. Material & Methods: A 51-year-old male patient with heterozygous CF due to muatations ΔF508/P205S, is being followed in Cystic Fibrosis Reference Center for about 10 years. In the last years, he has been consistently colonized with Methicilin-susceptible Staphylococcus aureus, Pseudomonas aeruginosa and Aspergillus section Fumigati whereby is under chronic suppression therapy with two inhaled antibiotics. Recently, there has been a progressive clinical respiratory functional deterioration. In a periodic evaluation, a miccrobiology control sputum was requested. Sample was cultured, in parallel, for bacteriol ogy and mycology evaluation. Results: Apart from detection of S. aureus and Raoultella ornithinolytica, after 3-5 days of incubation at 37ºC, the cultures showed several cream-coloured colonies, powdery to velvety. Microscopic examination showed hyaline septate hyphae, Penicillium-like conid iophores with rough wall, ovoid to cylindrical phyalides with a narrow neck and cylin drical unicellular smooth-walled microconidia, arranged in unbranched basipetal chains arising from phialides. The isolate was identified as Rasamsonia argillacea species complex based on its mor phology and confirmed by MALDI-TOF mass spectrometry. As no septate hyphae were seen on direct examination, a new sample was requested to exclude extrinsic contamina tion. The second sample was inoculated as previously, confirming the persistent presence of Rasamsonia argillacea species complex in the sputum of this patient. The identification of this isolate was further confirmed by sequencing the internal transcribed spacer (ITS) region of ribosomal DNA, showing 100% homology with sequences deposited on data bases. Antifungal susceptibility testing showed high minimal inhibitory concentrations (MIC) to almost all tested antifungals (posaconazole, voriconazole, amphotericin B) and low MIC to anidulafungin. The patient had no great exacerbation of his respiratory prob lems and the isolated fungus was interpreted as colonization being the patient under more frequent surveillance. Conclusion: Although colonization of the upper respiratory tract in CF patients by R. argillacea species complex has been described as an emerging situation, the role of these fungi in clinical or functional deterioration of the disease remains controversial. Indeed, data about its real prevalence in the CF population are lacking. However, taking into ac count the ability of this species to predominantly affect the lungs, to induce pneumonia and to disseminate to adjacent organs or even to the central nervous system (CNS) in imunocompromised patients, it is essential to promote its accurate identification that is often misidentified as Penicillium spp. or Paecilomyces species. Antifungal susceptibility testing should be performed for epidemiological purposes and to guide therapy, as Rasamsonia spp. usually presents a marked antifungal resistance profile
- Subcutaneous phaeohyphomycosis due to Phaeoacremonium parasiticum in a patient with Chronic Granulomatous DiseasePublication . Carvalho, Dinah; Sabino, Raquel; Veríssimo, Cristina; Simões, Helena; Lopes Silva, Susana; Marques, Tiago; Janeiro, João; Marques Lito, Luis; Melo Cristino, JoséObjectives: Phaeoacremonium parasiticum is a ubiquitous dematiaceous mold that rarely causes infection in humans. Its spectrum of disease ranges from subcutaneous infections to disseminated disease. The majority of those reported few cases involve immunocompromised patients. Chronic granulomatous disease (CGD) is an inherited disorder affecting nicotinamide adenine dinucleotide phosphate (NADPH) oxidase complex. CGD patients are susceptible to a broad spectrum of opportunistic infections, being fungal infections a major determinant of survival. We report a case of Subcutaneous phaeohyphomycosis due to P. parasiticum in a young adult with CGD. Material and methods: A 28-year-old male patient with autossomic recessive CGD, due to mutations in CYBA, is followed in Primary Immunodeficiency Center since childhood. He has been under prophylaxis with itraconazole, cotrimoxazole and IFNg and tapering oral steroids, started for granulomatous colitits 2 years earlier. In a regular visit to the clinical center, he complained of persistent pain on his left leg with no history of recent injury in the affected area and without external inflammatory signs. An ultrasound was performed after 2 weeks revealing a heterogeneous liquid of slightly irregular contour in the sinus of the left anterior tibial muscle with heterogeneity of the adjacent muscle. This piomiositis collection was punctured, under ultrasound control, with drainage of about 7cm3 of hemato-purulent exsudate that was promptly processed for bacteriology (aerobic and anaerobic) and mycology studies. Results: Cultures for bacteria were sterile. Culture on Sabouraud was positive after 5 days of incubation, showing slow growing and initially white colonies. Microscopic examination showed hyaline, septate mycelium with long, thin conidiophores and curved, aseptate conidia.The fungus was initially identified as an Acremonium sp. and was sent to the Mycology Reference Laboratory for molecular identification and antifungal susceptibility testing. Its identification was performed by sequencing the internal transcribed spacer (ITS) region of ribosomal DNA, being the isolate identified as Phaeoacremonium parasiticum (100% homology). After 3 weeks incubation, coloration of the colonies emerged, becoming greyish black upon subculture, with velvety texture and black reverse. Microscopically, pigmented hyphae with tapering, funnel-shaped phialides were observed, and conidia were hyaline and oblong, forming clusters at the tip of the phialides. At this point, macroscopic and microscopic morphology was consistent with Phaeoacremonium species. Susceptibility pattern showed low minimal inhibitory concentrations (MIC) to posaconazole and voriconazole, and higher MIC values to anidulafungin and amphotericin B. The patient has improved under voriconazol therapy (200 mg; bid) Conclusions: Phaeoacremonium parasiticum is an uncommon infection and its appropriate identification is often difficult because morphologically, the genus Phaeoacremonium show morphological features resembling both Acremonium and Phialophora genera. Molecular identification is determinant to confirm morphology, as many species have indistinguishable characteristics that may lead to incorrect antifungal options. Also, susceptibility testing should be done for these so rare fungi as optimal treatment has not yet been clearly defined.