Differential Thermotolerance Adaptation between Species of Coccidioides.

Coccidioidomycosis, or Valley fever, is caused by two species of dimorphic fungi. Based on molecular phylogenetic evidence, the genus Coccidioides contains two reciprocally monophyletic species: C. immitis and C. posadasii. However, phenotypic variation between species has not been deeply investigated. We therefore explored differences in growth rate under various conditions. A collection of 39 C. posadasii and 46 C. immitis isolates, representing the full geographical range of the two species, was screened for mycelial growth rate at 37 °C and 28 °C on solid media. The radial growth rate was measured for 16 days on yeast extract agar. A linear mixed effect model was used to compare the growth rate of C. posadasii and C. immitis at 37 °C and 28 °C, respectively. C. posadasii grew significantly faster at 37 °C, when compared to C. immitis; whereas both species had similar growth rates at 28 °C. These results indicate thermotolerance differs between these two species. As the ecological niche has not been well-described for Coccidioides spp., and disease variability between species has not been shown, the evolutionary pressure underlying the adaptation is unclear. However, this research reveals the first significant phenotypic difference between the two species that directly applies to ecological research.

Coccidioidal meningitis in non-AIDS patients. A case series at a Mexican neurological referral center.

BACKGROUND: Coccidioidal meningitis is a life-threatening condition and a diagnostic challenge in cases of chronic meningitis. It is associated to severe complications, like basal arachnoiditis, hydrocephalus, and secondary vasculitis. OBJECTIVE: To present a 20-year retrospective clinical series of coccidioidal meningitis cases at a Mexican neurological referral center. RESULTS: The clinical records of 11 patients, predominantly males, were retrieved. Weight loss and night sweats were observed in 64 % of cases. Neurological signs included intracranial hypertension in 91 % of cases, altered alertness and meningeal syndrome in 72 %, and neuropsychiatric symptoms in 64 %. Mean CSF glucose levels were 30 ± 25 mg/dL, and pleocytosis ranged from 0 to 2218 cells/mm3. The diagnosis was confirmed by coccidioidal antigen latex agglutination in 91 % of cases. Radiological findings were hepatomegaly in 55 % of cases and pneumonia in 45 %. Neuroimaging findings included leptomeningitis in 73 % of cases, pachymeningitis in 45 %, and vascular involvement in 91 %. Less common findings included spinal cord lesion and mycotic aneurism, found in 18 % of cases. A molecular coccidioidal DNA test confirmed the predominance of Coccidioides immitis, detected in 64 % of cases. With respect to the clinical outcome, 46 % of patients died. The survivors suffered from sequels like chronic headache, cognitive alterations, and depression. CONCLUSIONS: Coccidioidal meningitis is an entity with high mortality rates. More than one half of patients suffered disseminated disease. Although meningeal signs are not frequent in chronic meningitis, more than two-thirds of our patients showed mild nuchal rigidity. In addition, cerebral and cerebellar volume loss, associated with cognitive impairment and depression, was often observed in surviving patients during the clinical-radiological follow-up.

Candidosis vaginal: Revisión de la literatura y situación de México y otros países latinoamericanos / Vaginal Candidiasis: current situation of Mexico and other Latin American countries

Las levaduras del género Candida causan enfermedades en los humanos que abarcan desde infecciones superficiales no graves, hasta sistémicas y potencialmente mortales. La candidiasis o candidosis, es el origen común de enfermedad vaginal y aunque es una infección no considerada como incapacitante, suele causar síntomas molestos que alteran la conducta del paciente. En México se considera la única micosis de reporte obligatorio ante las autoridades sanitarias. Por lo anterior, en este trabajo se efectuó una revisión bibliográfica para conocer el estado del arte de la vulvovaginitis causada por Candida spp. (VVC), y ofrecer una breve descripción acerca de la frecuencia presentada por esta infección en diversos países de Latinoamérica, con especial énfasis en México. Se muestra que las frecuencias de VVC en Latinoamérica, son muy parecidas a las reportadas en países como Estados Unidos de América; asimismo, Candida albicans sigue prevaleciendo como el principal agente etiológico. Las diferencias encontradas entre países desarrollados con respecto a los latinoamericanos, consisten básicamente en los métodos diagnósticos y el tipo de tratamiento. Desafortunadamente, en México, a pesar de que la VVC ocupa el noveno lugar entre las 20 principales causas de enfermedad del país, en muy pocos casos se efectúa la identificación de la especie causante, lo que constituye un dato de importancia epidemiológica, considerado como la base para investigar los factores que aumentan el riesgo de contagio, en especial por especies Candida no-albicans y para determinar si la enfermedad es prevenible o controlable

Yeasts of the genus Candida cause diseases in humans ranging from superficial, non-serious, to systemic and potentially life-threatening infections. Candidiasis or thrush, is the common origin of vaginal disease and although it is not considered disabling, infection usually cause troublesome symptoms that alter the behavior of the patient. In Mexico it is considered the unique mycosis of mandatory reporting to health authorities. Therefore, in this work a literature review was conducted to know the state of the art of the vulvovaginitis caused by Candida spp. (VVC), as well as provide a brief description about the frequency presented by this infection in different countries of Latin America, with special emphasis on Mexico. It shows that the frequencies of VVC in Latin America, are very similar to those reported in countries such as the United States of America; in addition, Candida albicans still prevails as the main etiologic agent. The differences found between developed countries with respect to Latin American countries basically consist of the diagnostic methods and the type of treatment. Unfortunately, in Mexico, while the VVC ranks ninth among the 20 principal causes of disease in the country, in very few cases is carried out the identification of the causative species, which constitutes a fact of epidemiological importance, considered as the basis for investigating the factors that increase the risk of infection, especially by Candida nonalbicans species and to determine if the disease is preventable or controllable

International Society of Human and Animal Mycology (ISHAM)-ITS reference DNA barcoding database--the quality controlled standard tool for routine identification of human and animal pathogenic fungi.

Human and animal fungal pathogens are a growing threat worldwide leading to emerging infections and creating new risks for established ones. There is a growing need for a rapid and accurate identification of pathogens to enable early diagnosis and targeted antifungal therapy. Morphological and biochemical identification methods are time-consuming and require trained experts. Alternatively, molecular methods, such as DNA barcoding, a powerful and easy tool for rapid monophasic identification, offer a practical approach for species identification and less demanding in terms of taxonomical expertise. However, its wide-spread use is still limited by a lack of quality-controlled reference databases and the evolving recognition and definition of new fungal species/complexes. An international consortium of medical mycology laboratories was formed aiming to establish a quality controlled ITS database under the umbrella of the ISHAM working group on "DNA barcoding of human and animal pathogenic fungi." A new database, containing 2800 ITS sequences representing 421 fungal species, providing the medical community with a freely accessible tool at http://www.isham.org/ and http://its.mycologylab.org/ to rapidly and reliably identify most agents of mycoses, was established. The generated sequences included in the new database were used to evaluate the variation and overall utility of the ITS region for the identification of pathogenic fungi at intra-and interspecies level. The average intraspecies variation ranged from 0 to 2.25%. This highlighted selected pathogenic fungal species, such as the dermatophytes and emerging yeast, for which additional molecular methods/genetic markers are required for their reliable identification from clinical and veterinary specimens.

Candidosis vaginal. primera parte: revisión de la clínica, epidemiología y situación de México / Vaginal candidiasis. first part: epidemiology and current state of Mexico

En esta sección se presentan los datos de diversos autores en cuanto a etiología, epidemiología, fisiopatogenia y el perfil clínico de la candidosis o candidiasis vulvo vaginal, con especial atención al escenario actual en México, país en donde es la única micosis de reporte obligatorio ante las autoridades sanitarias, situación que nos motivó a efectuar la presente revisión bibliográfica. La literatura evaluada contempló el período 2007-2013. La vulvovaginitis por Candida spp (VVC), es una infección que habitualmente no se considera incapacitante, aunque sus manifestaciones clínicas pueden dar lugar a gran estrés en las pacientes. En México, los estudios epidemiológicos, han estado enfocados, principalmente, a describir la frecuencia con la que Candida se asocia a casos de vulvo vaginitis y la respuesta clínica a diferentes terapias; sin embargo, es evidente la falta de estudios que relacionen la presencia de Candida con diversos factores de riesgo, la frecuencia de mujeres que recurren a la automedicación y estudios enfocados a la fisiopatología de la vulvo vaginitis causada por este patógeno. Según la literatura consultada, todas estas circunstancias son conocidas y siguen siendo motivo de estudio en países desarrollados.

This section presents data from different authors in terms of etiology, epidemiology, physiopathogeny and the clinical profile of vulvovaginal candidiasis or vulvovaginal candidosis, with special attention to the current scenario in Mexico, a country where it is the only mycosis of mandatory reporting to health authorities, situation that motivated us to carry out the present literature review. The assessed literature took into account the 2007- 2013 period. The vulvovaginitis by Candida spp. (VVC), is an infection that usually is not considered disabling, but its clinical manifestations can give rise to great stress in patients. In Mexico, the epidemiological studies have been focused, primarily, in describing the frequency with which Candida is associated with cases of vulvovaginitis and the clinical response to different therapies; However, it is evident the lack of studies that relate the presence of Candida with different risk factors, the frequency of women who resort to selfmedication and studies focused on the pathophysiology of the vulvovaginitis caused by this pathogen. According to the literature consulted, these circumstances are known and are still cause for study in developed countries.

Combining forces--the use of Landsat TM satellite imagery, soil parameter information, and multiplex PCR to detect Coccidioides immitis growth sites in Kern County, California.

Coccidioidomycosis is a fungal disease acquired through the inhalation of spores of Coccidioides spp., which afflicts primarily humans and other mammals. It is endemic to areas in the southwestern United States, including the San Joaquin Valley portion of Kern County, California, our region of interest (ROI). Recently, incidence of coccidioidomycosis, also known as valley fever, has increased significantly, and several factors including climate change have been suggested as possible drivers for this observation. Up to date details about the ecological niche of C. immitis have escaped full characterization. In our project, we chose a three-step approach to investigate this niche: 1) We examined Landsat-5-Thematic-Mapper multispectral images of our ROI by using training pixels at a 750 m × 750 m section of Sharktooth Hill, a site confirmed to be a C. immitis growth site, to implement a Maximum Likelihood Classification scheme to map out the locations that could be suitable to support the growth of the pathogen; 2) We used the websoilsurvey database of the US Department of Agriculture to obtain soil parameter data; and 3) We investigated soil samples from 23 sites around Bakersfield, California using a multiplex Polymerase Chain Reaction (PCR) based method to detect the pathogen. Our results indicated that a combination of satellite imagery, soil type information, and multiplex PCR are powerful tools to predict and identify growth sites of C. immitis. This approach can be used as a basis for systematic sampling and investigation of soils to detect Coccidioides spp.

AFLP analysis reveals high genetic diversity but low population structure in Coccidioides posadasii isolates from Mexico and Argentina.

BACKGROUND: Coccidioides immitis and C. posadasii cause coccidioidomycosis, a disease that is endemic to North and South America, but for Central America, the incidence of coccidioidomycosis has not been clearly established. Several studies suggest genetic variability in these fungi; however, little definitive information has been discovered about the variability of Coccidioides fungi in Mexico (MX) and Argentina (AR). Thus, the goals for this work were to study 32 Coccidioides spp. isolates from MX and AR, identify the species of these Coccidioides spp. isolates, analyse their phenotypic variability, examine their genetic variability and investigate the Coccidioides reproductive system and its level of genetic differentiation. METHODS: Coccidioides spp. isolates from MX and AR were taxonomically identified by phylogenetic inference analysis using partial sequences of the Ag2/PRA gene and their phenotypic characteristics analysed. The genetic variability, reproductive system and level of differentiation were estimated using AFLP markers. The level of genetic variability was assessed measuring the percentage of polymorphic loci, number of effective allele, expected heterocygosity and Index of Association (IA). The degree of genetic differentiation was determined by AMOVA. Genetic similarities among isolates were estimated using Jaccard index. The UPGMA was used to contsruct the corresponding dendrogram. Finally, a network of haplotypes was built to evaluate the genealogical relationships among AFLP haplotypes. RESULTS: All isolates of Coccidioides spp. from MX and AR were identified as C. posadasii. No phenotypic variability was observed among the C. posadasii isolates from MX and AR. Analyses of genetic diversity and population structure were conducted using AFLP markers. Different estimators of genetic variability indicated that the C. posadasii isolates from MX and AR had high genetic variability. Furthermore, AMOVA, dendrogram and haplotype network showed a small genetic differentiation among the C. posadasii populations analysed from MX and AR. Additionally, the IA calculated for the isolates suggested that the species has a recombinant reproductive system. CONCLUSIONS: No phenotypic variability was observed among the C. posadasii isolates from MX and AR. The high genetic variability observed in the isolates from MX and AR and the small genetic differentiation observed among the C. posadasii isolates analysed, suggest that this species could be distributed as a single genetic population in Latin America.

Clinical comparison of two Mexican coccidioidins.

Coccidioidin, an extract from the saprophytic mycelial form of Coccidioides spp., has been a very useful antigen preparation both for skin and serological tests for coccidioidomycosis. Unfortunately, coccidioidin is not currently available for skin testing in the United States. Coccidioidin has been produced commercially in Mexico by a vaccine and reagents laboratory of the Mexican Federal Government. It also has been produced at the Microbiology Laboratory of the Faculty of Medicine, Universidad Nacional Autónoma de México exclusively as an antigen for research projects. The objective of the study was to compare both coccidioidins in their reactivity and safety when applied in humans. One hundred and eighty-four volunteers were tested; median age was 33 (range 14-82). When the cutoff point is set in 5 mm, 88 subjects (47.8%) had a positive test for the commercial coccidioidin and 76 (41.3%; CI(95%) 0.50, 1.15; P = 0.20) were positive with the research antigen. Seventy-five subjects were positive for both antigens and 96 were negative for both. Fifty-nine subjects (31.3%) reported an adverse reaction after the application of the antigen; they were mostly very mild local reactions. Mexican research coccidioidin is a safe and reliable antigen that can be used for the detection of coccidioidomycosis infection in mammals.