Expanding understanding of epidemiology of coccidioidomycosis in the Western hemisphere

Overview of the Current Challenges in Pulmonary Coccidioidomycosis

Coccidioidomycosis is a disease caused by soil fungi of the genus Coccidioides, divided genetically into Coccidioides immitis (California isolates) and Coccidioides posadasii (isolates outside California). Coccidioidomycosis is transmitted through the inhalation of fungal spores, arthroconidia, which can cause disease in susceptible mammalian hosts, including humans. Coccidioidomycosis is endemic to the western part of the United States of America, including the central valley of California, Arizona, New Mexico, and parts of western Texas. Cases have been reported in other regions in different states, and endemic pockets are present in these states. The incidence of reported cases of coccidioidomycosis has notably increased since it became reportable in 1995. Clinically, the infection ranges from asymptomatic to fatal disease due to pneumonia or disseminated states. The recognition of coccidioidomycosis can be challenging, as it frequently mimics bacterial community-acquired pneumonia. The diagnosis of coccidioidomycosis is frequently dependent on serologic testing, the results of which can take several days or longer to obtain. Coccidioidomycosis continues to present challenges for clinicians, and suspected cases can be easily missed. The challenges of coccidioidomycosis disease, from presentation to diagnosis to treatment, remain a hurdle for clinicians, and further research is needed to address these challenges.

Discovery of a Unique Set of Dog-Seroreactive Coccidioides Proteins Using Nucleic Acid Programmable Protein Array

Valley Fever (VF), caused by fungi in the genus Coccidioides, is a prevalent disease in southwestern and western parts of the United States that affects both humans and animals, such as dogs. Although the immune responses to infection with Coccidioides spp. are not fully characterized, antibody-detection assays are used in conjunction with clinical presentation and radiologic findings to aid in the diagnosis of VF. These assays often use Complement Fixation (CF) and Tube Precipitin (TP) antigens as the main targets of IgG and IgM reactivity, respectively. Our group previously reported evidence of over 800 genes expressed at the protein level in C. posadasii. However, antibody reactivity to the majority of these proteins has never been explored. Using a new, high-throughput screening technology, the Nucleic Acid Programmable Protein Array (NAPPA), we screened serum specimens from dogs against 708 of these previously identified proteins for IgG reactivity. Serum from three separate groups of dogs was analyzed and revealed a small panel of proteins to be further characterized for immuno-reactivity. In addition to CF/CTS1 antigen, sera from most infected dogs showed antibody reactivity to endo-1,3-betaglucanase, peroxisomal matrix protein, and another novel reactive protein, CPSG_05795. These antigens may provide additional targets to aid in antibody-based diagnostics.

Epidemiological, clinical, and genomic landscape of coccidioidomycosis in northeastern Brazil

Coccidioidomycosis, listed as a priority mycosis by the WHO, is endemic in the United States but often overlooked in Central and South America. Employing a multi-institutional approach, we investigate how disease characteristics, pathogen genetic variation, and environmental factors impact coccidioidomycosis epidemiology and outcomes in South America. We identified 292 cases (1978-2021) and 42 outbreaks in Piauí and Maranhão states, Brazil, the largest series outside the US/Mexico epidemic zone. The male-to-female ratio was 57.4:1 and the most common activity was armadillo hunting (91.1%) 4 to 30 days before symptom onset. Most patients (92.8%) exhibited typical acute pulmonary disease, with cough (93%), fever (90%), and chest pain (77%) as predominant symptoms. The case fatality rate was 8%. Our negative binomial regression model indicates that reduced precipitation levels in the current (p = 0.015) and preceding year (p = 0.001) predict heightened incidence. Unlike other hotspots, acidic soil characterizes this region. Brazilian strains differ genomically from other C. posadasii lineages. Northeastern Brazil presents a distinctive coccidioidomycosis profile, with armadillo hunters facing elevated risks. Low annual rainfall emerges as a key factor in increasing cases. A unique C. posadasii lineage in Brazil suggests potential differences in environmental, virulence, and/or pathogenesis traits compared to other Coccidioides genotypes.

Valley fever, mimicker of malignancy

Coccidioidomycosis rates in endemic areas such as California and Arizona have been increasing in recent years. Most common manifestations in symptomatic individuals involve the lungs. Disseminated disease occurs when the infection spreads beyond the lungs. Disseminated disease occurs in about 1% of all coccidiomycosis cases. Diagnosis in classically non-endemic regions can be difficult as coccidiomycosis can mimic a variety of other illnesses which can lead to delays in initiating appropriate therapy. We report a case of severe disseminated coccidiomycosis involving the soft tissue, bone, and intra-abdominal organs in a previously healthy individual that was initially thought to be a malignancy. With climate change possibly altering the traditional endemic regions and expanding Coccidioides to new territories, this case reinforces the importance of maintaining a broad differential as well as awareness of disease manifestations for healthcare providers who do not regularly treat Coccidioides.

Pulmonary and Extrapulmonary Manifestations of Fungal Infections Misdiagnosed as Tuberculosis: The Need for Prompt Diagnosis and Management

Fungal infections commonly present with myriad symptoms that mimic other clinical entities, notable amongst which is tuberculosis. Besides histoplasmosis and chronic pulmonary aspergillosis, which can mimic TB, this review has identified several other fungal infections which also do. A total of 80 individual cases misdiagnosed as TB are highlighted: aspergillosis (n = 18, 22.5%), histoplasmosis (n = 16, 20%), blastomycosis (n = 14, 17.5%), cryptococcosis (n = 11, 13.8%), talaromycosis (n = 7, 8.8%), coccidioidomycosis (n = 5, 6.3%), mucormycosis (n = 4, 5%), sporotrichosis (n = 3, 3.8%), phaeohyphomycosis (n = 1, 1.3%) and chromoblastomycosis (n = 1, 1.3%). Case series from India and Pakistan reported over 100 cases of chronic and allergic bronchopulmonary aspergillosis had received anti-TB therapy before the correct diagnosis was made. Forty-five cases (56.3%) had favorable outcomes, and 25 (33.8%) died, outcome was unclear in the remainder. Seventeen (21.3%) cases were infected with human immunodeficiency virus (HIV). Diagnostic modalities were histopathology (n = 46, 57.5%), culture (n = 42, 52.5%), serology (n = 18, 22.5%), cytology (n = 2, 2.5%), gene sequencing (n = 5, 6.3%) and microscopy (n = 10, 12.5%) including Gram stain, India ink preparation, bone marrow smear and KOH mount. We conclude that the above fungal infections should always be considered or ruled out whenever a patient presents with symptoms suggestive of tuberculosis which is unconfirmed thereby reducing prolonged hospital stay and mortalities associated with a delayed or incorrect diagnosis of fungal infections.

Coccidioidomycosis: A Contemporary Review

Coccidioidomycosis, colloquially known as Valley Fever, is an invasive dimorphic fungal infection caused by Coccidioides immitis and C. posadasii. The fungi are found in the arid desert soils of the southwestern US, as well as in parts of Mexico and Central and South America. Acquisition is typically via inhalation of arthroconidia which become airborne after both natural (e.g., earthquakes, dust storms, and fires) and human-related events (e.g., military maneuvers, recreational activities, agriculture, and construction). The incidence of infection in increasing likely a result of both climatic and populational changes. Further, the recognized geographic distribution of Coccidioides spp. is expanding, as cases are being diagnosed in new areas (e.g., eastern Washington, Oregon, and Utah). Most coccidioidal infections are asymptomatic (60%); however, approximately one-third develop a pulmonary illness which is a leading cause of community-acquired pneumonia in highly endemic areas. Uncommonly (0.5–2% of cases), the infection disseminates to extrapulmonary locations (e.g., skin, bones/joints, and the central nervous system), and is most commonly seen among persons with cellular immunodeficiencies (e.g., transplant recipients, HIV, and pregnancy) and non-Caucasian races (especially African Americans and Filipinos). The diagnosis of coccidioidomycosis requires astute clinical suspicion and laboratory findings, including positive serology, cultures, and/or histopathology results. Treatment is warranted among persons with pneumonia who have risk factors for complicated disease and among those with extrapulmonary disease. Novel antifungals with improved fungicidal activity and rapidity of action with fewer side effects and drug interactions are needed. Preventive strategies (e.g., education regarding the disease, dust avoidance, mask wearing, including among select groups, antifungal prophylaxis, and surveillance laboratory testing) are advised for residents and travelers to endemic areas. Currently, no preventive vaccine is available. Coccidioidomycosis has been recognized for over a century, and an expanding wealth of knowledge has been gained regarding this emerging infectious disease which will be reviewed here.

FDA Public Workshop Summary-Coccidioidomycosis (Valley Fever): Considerations for Development of Antifungal Drugs

Coccidioidomycosis is a fungal disease endemic to the southwestern United States, Mexico, and Central and South America. Prevalence rates are increasing steadily and new endemic areas of Coccidioides are emerging. Standard treatment is often administered for months to decades, and intolerance to medications and treatment failures are common. No new treatments for coccidioidomycosis have been approved in the U.S. in nearly 40 years. On August 5, 2020, the U.S. Food and Drug Administration convened experts in coccidioidomycosis from academia, industry, patient groups and other government agencies to discuss the disease landscape and strategies to facilitate product development for treatment of coccidioidomycosis. This paper summarizes the key topics concerning drug development for coccidioidomycosis presented by speakers and panelists during the workshop, such as unmet need, trial designs, endpoints, incentives, research and development support, and collaborations to facilitate antifungal drug development.

Cross-sectional imaging findings of splenic infections: is differential diagnosis possible?

The spleen plays an important role in the immunological homeostasis of the body. Several neoplastic and non-neoplastic diseases may affect this organ, and imaging is of fundamental importance for diagnosis. Infectious diseases of the spleen can be encountered in daily radiology practice, and differential diagnosis may sometimes be challenging. Infectious involvement of the spleen can be primary or secondary to a different source outside the spleen. Despite the fact that different infectious diseases may cause similar imaging findings, we believe that differential diagnosis between different causes may also be possible in certain patients with imaging. Early diagnosis may potentially enhance patients’ treatment and outcome. In this review, we aimed to increase imaging specialists’ awareness of splenic infections by describing the multimodality imaging features of common and atypical infections of the spleen with their differential diagnoses.

Disseminated Coccidioidomycosis to the Gallbladder

Coccidioidomycosis is an infection caused by inhalation of arthroconidia produced by dimorphic fungi in the genus Coccidioides. Forty percent of patients will develop an influenza-like illness with symptoms suggestive of a mild and self-limited respiratory infection; however, 5% of these individuals will develop extrapulmonary disseminated disease. An immunocompromised patient presented with right upper quadrant pain, ultrasound with pericholecystic fluid, in which a percutaneous cholecystostomy contained biliary fluid that grew the fungus Coccidioides immitis. Patient was initiated on intravenous amphotericin therapy and was followed closely with postoperative bile drainage with eventual laparoscopic cholecystectomy. We present a very rare case of disseminated coccidioidomycosis to the gallbladder.

Occupational Respiratory Infections

Occupational respiratory infections can be caused by bacterial, viral, and fungal pathogens. Transmission in occupational settings can occur from other humans, animals, or the environment, and occur in various occupations and industries. In this article, we describe 4 occupationally acquired respiratory infections at the focus of NIOSH investigations over the last decade: tuberculosis (TB), influenza, psittacosis, and coccidioidomycosis. We highlight the epidemiology, clinical manifestations, occupational risk factors, and prevention measures.

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.

Infectious Lung Disease

Infectious diseases are one of the main causes of morbidity and mortality worldwide. With new pathogens continuously emerging, known infectious diseases reemerging, increasing microbial resistance to antimicrobial agents, global environmental change, ease of world travel, and an increasing immunosuppressed population, recognition of infectious diseases plays an ever-important role in surgical pathology. This becomes particularly significant in cases where infectious disease is not suspected clinically and the initial diagnostic workup fails to include samples for culture. As such, it is not uncommon that a lung biopsy becomes the only material available in the diagnostic process of an infectious disease. Once the infectious nature of the pathological process is established, careful search for the causative agent is advised. This can often be achieved by examination of the hematoxylin and eosin-stained sections alone as many organisms or their cytopathic effects are visible on routine staining. However, ancillary studies such as histochemical stains, immunohistochemistry, in situ hybridization, or molecular techniques may be needed to identify the organism in tissue sections or for further characterization, such as speciation.

Expansion of Coccidioidomycosis Endemic Regions in the United States in Response to Climate Change

Coccidioidomycosis (Valley fever) is a fungal disease endemic to the southwestern United States. Across this region, temperature and precipitation influence the extent of the endemic region and number of Valley fever cases. Climate projections for the western United States indicate that temperatures will increase and precipitation patterns will shift, which may alter disease dynamics. We estimated the area potentially endemic to Valley fever using a climate niche model derived from contemporary climate and disease incidence data. We then used our model with projections of climate from Earth system models to assess how endemic areas will change during the 21st century. By 2100 in a high warming scenario, our model predicts that the area of climate-limited endemicity will more than double, the number of affected states will increase from 12 to 17, and the number of Valley fever cases will increase by 50%. The Valley fever endemic region will expand north into dry western states, including Idaho, Wyoming, Montana, Nebraska, South Dakota, and North Dakota. Precipitation will limit the disease from spreading into states farther east and along the central and northern Pacific coast. This is the first quantitative estimate of how climate change may influence Valley fever in the United States. Our predictive model of Valley fever endemicity may provide guidance to public health officials to establish disease surveillance programs and design mitigation efforts to limit the impacts of this disease.

Design and evaluation of an AFLP molecular marker for the detection of Coccidioides spp. in biological samples

At present, there is no standardized marker that is routinely used in clinical laboratories to diagnose coccidioidomycosis. Thus, the goals of this study were to obtain a sequence characterized amplified region (SCAR) marker for the identification of Coccidioides spp., evaluate its specificity and sensitivity in fungal DNA-spiked blood and sputum samples, and compare it with previously described molecular markers. Specific amplified fragment length polymorphism (AFLP) amplicons for Coccidioides immitis and Coccidioides posadasii were cloned into the vector pGEM® -T Easy vector and sequenced to develop a SCAR marker. Oligonucleotides were designed to identify Coccidioides spp. by polymerase chain reaction (PCR), and the specificity and sensitivity of these oligonucleotides were tested with the DNA from related pathogens. The specificity and sensitivity of the SCAR marker was evaluated with blood and sputum samples spiked with Coccidioides DNA and compared with other previously described markers (621, GAC2, and Ag2/PRA). In addition, the conditions for its use were established using biological samples. A specific marker named SCAR₃₀₀ was obtained to identify Coccidioides spp. that exhibited good sensitivity and specificity. The results showed that all of the markers tested in this study can identify Coccidioides spp. However, the SCAR₃₀₀ and 621 markers were the most sensitive, whereas the SCAR₃₀₀ marker was the most specific. Thus, the SCAR₃₀₀ marker is a useful tool to identify Coccidioides spp.

Coccidioidomycosis: Epidemiology, Fungal Pathogenesis, and Therapeutic Development

Purpose of Review

Coccidioidomycosis can result from the inhalation of infectious spores of Coccidioides species (spp.) immitis or posadasii. Clinical manifestations range from mild flu-like disease to severe disseminated infection that can require life-long therapy. Burden of this mycosis is high in the southwest region of the USA where it is well characterized, and in many areas of Mexico and Latin America where it is inadequately characterized. Here, we provide historical data and current knowledge on Coccidioides spp. pathogenesis as well as recent progress in therapeutic and vaccine development against coccidioidomycosis.

Recent Findings

The virulence mechanisms of Coccidioides spp. are largely unknown; however, production and regulation of a spherule glycoprotein, ammonium production, and melanization have all been proposed as integral factors in Coccidioides spp.' pathogenesis. Therapeutic options are limited and not 100% effective, but individualized treatment with triazoles or amphotericin B over the course of pulmonary or disseminated infection can be effective in resolution of coccidioidomycosis. Human immunization has not been achieved but efforts are ongoing.

Summary

Advances in therapeutic and vaccine development are imperative for the prevention and treatment of coccidioidomycosis, especially for those individuals at risk either living or traveling to or from endemic areas.

Occupational coccidioidomycosis surveillance and recent outbreaks in California

Workers in Coccidioides-endemic areas performing soil-disturbing work or exposed to windy and dusty conditions are at increased risk for coccidioidomycosis. Four occupational coccidioidomycosis outbreaks from 2007 to 2014 in California are described, involving construction workers in a number of excavation projects and an outdoor filming event involving cast and crew. These outbreaks highlight the importance of identifying industries and occupations at high risk for coccidioidomycosis, conducting targeted occupational health surveillance to assess the burden of illness, developing and implementing prevention strategies, and setting research priorities.

Coccidioidomycosis in Latin America

Coccidioidomycosis is a highly prevalent systemic mycosis in Latin America and has been reported (human and zoonotic cases) in México, Guatemala, Honduras, Colombia, Venezuela, Brazil, Paraguay, Bolivia, and Argentina. The incidence of coccidioidomycosis in Latin America is unknown due to lack of clinical awareness and limited access to laboratory diagnosis. Coccidioidomycosis is as prevalent in Mexico as in the endemic regions of the United States. The number of cases reported in Brazil and Argentina has progressively increased during the last decade, including areas that were not considered as endemic. Genetic studies have shown that the prevalent species in Latin America is Coccidioides posadasii. Coccidioides immitis has been reported sporadically in indigenous cases from Mexico and Colombia. Coccidioidomycosis and tuberculosis share some risk factors such as immunosuppression and residing in areas endemic for these conditions, so their coexistence in the same patient is not uncommon in Latin America. In most regions, clinical diagnosis of coccidioidomycosis is based on direct sputum examination and histopathology results from biopsies or autopsies. This would explain why primary coccidioidomycosis is rarely diagnosed, and most cases published are about chronic pulmonary or disseminated disease.

Coccidioides ecology and genomics

Although the natural history and ecology of Coccidioides spp. have been studied for over 100 years, many fundamental questions about this fungus remain unanswered. Two of the most challenging aspects of the study of Coccidioides have been the undefined ecological niche and the outdated geographic distribution maps dating from midcentury. This review details the history of Coccidioides ecological research, and discusses current strategies and advances in understanding Coccidioides genetics and ecology.

A paleopathological approach to early human adaptation for wet-rice agriculture: The first case of Neolithic spinal tuberculosis at the Yangtze River Delta of China

The earliest evidence of human tuberculosis can be traced to at least the early dynastic periods, when full-scaled wet-rice agriculture began or entered its early developmental stages, in circum-China countries (Japan, Korea, and Thailand). Early studies indicated that the initial spread of tuberculosis coincided with the development of wet-rice agriculture. It has been proposed that the adaptation to agriculture changed human social/living environments, coincidentally favoring survival and spread of pathogenic Mycobacterial strains that cause tuberculosis. Here we present a possible case of spinal tuberculosis evident in the remains of a young female (M191) found among 184 skeletal individuals who were Neolithic wet-rice agriculturalists from the Yangtze River Delta of China, associated with Songze culture (3900-3200 B.C.). This early evidence of tuberculosis in East Asia serves as an example of early human morbidity following the adoption of the wet-rice agriculture.

Social, environmental and microbiologic aspects of endemic mycoses in Brazil

Many factors that lead to host immunosuppression are clearly known to predispose the host to fungal diseases, significantly influencing the occurrence of mycoses. However, little or nothing has been discussed regarding social or economic factors that can influence the occurrence of diseases caused by fungi. In this minireview, we discuss several factors that may affect the occurrence of mycoses in Brazil, a continentally extended country that is marked by large climatic variations and severe socioeconomic distortions that may limit access to health services for the population.

Locus Minoris Resistentiae in Coccidioidomycosis: A Case Series

Locus minoris resistentiae refers to decreased resistance in any internal organ or external body region, leaving it more vulnerable to disease processes than other regions. These changes, either congenital or acquired, alter the defense capacity. The concept of locus minoris resistentiae is widely accepted in the medical field and presents itself across specialties. Antecedent trauma is a known risk factor for hematogenous dissemination of infection; this also applies to coccidioidal species. In this article, we describe 2 patients who suffered from pulmonary coccidioidomycosis with subsequent trauma resulting in osseous dissemination to the site of injury.

Coccidioidomycosis in alpacas in the southwestern United States

An anonymous web-based survey of alpaca owners was used to learn more about the clinical presentation, diagnosis, and treatment of coccidioidomycosis in alpacas in the United States. Thirty-seven owners, with 1,117 alpacas, completed the survey. Over 4% of alpacas included in the study were diagnosed with coccidioidomycosis between 2005 and 2016 (5 post mortem, 46 clinically). Immunodiffusion titers ranged from 1:4 to ≥1:256 in sick animals. Alpacas residing in Arizona counties with a high incidence of human disease were 5.8 times more likely to contract coccidioidomycosis than animals residing in other areas of the state. Treatment was reported in 23 alpacas, and 78% of those animals died or were euthanized. Necropsy records from a veterinary diagnostic laboratory in Tucson, AZ were reviewed to estimate the severity of disease in this species. Nine cases identified for review died of disseminated coccidioidomycosis; the disease was extensive in most animals, with the lungs, lymph nodes, and liver the most frequently affected. Alpacas appear to be highly susceptible to severe illness as a result of infection by Coccidioides spp., frequently resulting in death. More research is needed to better understand the epidemiology, clinical signs, and treatment protocols for coccidioidomycosis in alpacas.

Selection of Specific Peptides for Coccidioides spp. Obtained from Antigenic Fractions through SDS-PAGE and Western Blot Methods by the Recognition of Sera from Patients with Coccidioidomycosis

Antigenic fractions of 100, 50, 37, and 28 kDa obtained through the SDS-PAGE method that were more frequently recognized by anti-Coccidioides antibodies in the sera of coccidioidomycosis patients were selected using western blotting. Subsequently, these bands were sequenced, and the obtained proteins were analysed by BLAST to choose peptides specific for Coccidioides spp. from among the shared aligned sequences of related fungi. A peptide specific for C. immitis was selected from the "GPI anchored serine-threonine rich protein OS C. immitis", while from the "uncharacterized protein of C. immitis", we selected a peptide for C. immitis and C. posadasii. These proteins arose from the 100 kDa antigenic fraction. From the protein "fatty acid amide hydrolase 1 of C. posadasii" that was identified from the 50 kDa antigenic fraction, a peptide was selected that recognized C. immitis and C. posadasii. In addition, the analysis of all the peptides (353) of each of the assembled proteins showed that only 35 had 100% identity with proteins of C. immitis and C. posadasii, one had 100% identity with only C. immitis, and one had 100% identity with only C. posadasii. These peptides can be used as diagnostic reagents, vaccines, and antifungals.

Common Child and Adolescent Cutaneous Infestations and Fungal Infections

Cutaneous infections and infestations are common among children and adolescents. Ectoparasitic infestations affect individuals across the globe. Head lice, body lice, scabies, and infestations with bed bugs are seen in individuals who reside in both resource poor areas and in developed countries. Superficial cutaneous and mucosal candida infections occur throughout the life cycle. Dermatophyte infections of keratin-containing skin and skin structures result in tinea capitis (scalp), tinea corporis (body), tinea pedis (foot), and tinea unguium (nails). Less frequent endemic fungal infections such as blastomycosis, coccidiodomycosis, and histoplasmosis may present with skin findings. This article will describe the epidemiology and transmission of these conditions as well as their clinical manifestations. The approach to diagnosis will be addressed as well as primary prevention and current therapies.

Travel-related risk factors for coccidioidomycosis

BACKGROUND

Coccidioidomycosis is a regionally endemic systemic mycosis with unique risk factors. Since people travel for business or pleasure, and often in conjunction with their avocations or hobbies, the objectives of this review were to describe these and other risk factors for coccidioidomycosis; to alert travel medicine clinicians to the different presenting manifestations of coccidioidomycosis; and to recommend effective treatment, disease control and prevention strategies.

METHODS

To meet the objectives of this review, Internet search engines were queried with the keywords as medical subject headings over the study period, 1970-2017.

RESULTS

The principle transmission mechanism of coccidioidomycosis is by deep inhalation of aerosolized arthroconidia with resulting symptomatic pulmonary infections ranging from febrile influenza-like illnesses to fatal disseminated mycoses. In addition to residency or travel in endemic areas, persons immunocompromised by advancing age, pregnancy, cancer, corticosteroid therapy, diabetes, organ transplantation and human immunodeficiency virus infection are at significantly increased risks of contracting coccidioidomycosis. Persons of African, Asian, Filipino and Hispanic descent are also at increased risks of contracting coccidioidomycosis. Hobbies associated with coccidioidomycosis have included armadillo hunting, model airplane flying and archaeological digging. Occupational risk factors for coccidioidomycosis include endemic exposures during military maneuvers, outdoor track and field events, road construction, solar-power and wind-power farm construction, archaeological excavation and prison work.

CONCLUSIONS

Coccidioidomycosis is more common in endemic and non-endemic areas than previously recognized and can result in considerable morbidity and mortality. Coccidioidomycosis is increasingly imported from endemic areas in the Western Hemisphere to non-endemic areas worldwide. Increased awareness of disease risk factors among the public and the international healthcare community will improve the timely diagnosis and treatment of coccidioidomycosis and prevent disease progression, dissemination and deaths in residents in and in travellers returning from endemic regions. A vaccine for the primary prevention of coccidioidomycosis would be cost-effective.

Investigating Clinical Issues by Genotyping of Medically Important Fungi: Why and How?

Genotyping studies of medically important fungi have addressed elucidation of outbreaks, nosocomial transmissions, infection routes, and genotype-phenotype correlations, of which secondary resistance has been most intensively investigated. Two methods have emerged because of their high discriminatory power and reproducibility: multilocus sequence typing (MLST) and microsatellite length polymorphism (MLP) using short tandem repeat (STR) markers. MLST relies on single-nucleotide polymorphisms within the coding regions of housekeeping genes. STR polymorphisms are based on the number of repeats of short DNA fragments, mostly outside coding regions, and thus are expected to be more polymorphic and more rapidly evolving than MLST markers. There is no consensus on a universal typing system. Either one or both of these approaches are now available for Candida spp., Aspergillus spp., Fusarium spp., Scedosporium spp., Cryptococcus neoformans, Pneumocystis jirovecii, and endemic mycoses. The choice of the method and the number of loci to be tested depend on the clinical question being addressed. Next-generation sequencing is becoming the most appropriate method for fungi with no MLP or MLST typing available. Whatever the molecular tool used, collection of clinical data (e.g., time of hospitalization and sharing of similar rooms) is mandatory for investigating outbreaks and nosocomial transmission.

Remote sensing observation of annual dust cycles and possible causality of Kawasaki disease outbreaks in Japan

Kawasaki disease (KD) is a rare vascular disease that, if left untreated, can result in irreparable cardiac damage in children. While the symptoms of KD are well-known, as are best practices for treatment, the etiology of the disease and the factors contributing to KD outbreaks remain puzzling to both medical practitioners and scientists alike. Recently, a fungus known as Candida, originating in the farmlands of China, has been blamed for outbreaks in China and Japan, with the hypothesis that it can be transported over long ranges via different wind mechanisms. This paper provides evidence to understand the transport mechanisms of dust at different geographic locations and the cause of the annual spike of KD in Japan. Candida is carried along with many other dusts, particles or aerosols, of various sizes in major seasonal wind currents. The evidence is based upon particle categorization using the Moderate Resolution Imaging Spectrometer (MODIS) Aerosol Optical Depth (AOD), Fine Mode Fraction (FMF) and Ångström Exponent (AE), the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) attenuated backscatter and aerosol subtype, and the Aerosol Robotic Network's (AERONET) derived volume concentration. We found that seasonality associated with aerosol size distribution at different geographic locations plays a role in identifying dominant abundance at each location. Knowing the typical size of the Candida fungus, and analyzing aerosol characteristics using AERONET data reveals possible particle transport association with KD events at different locations. Thus, understanding transport mechanisms and accurate identification of aerosol sources is important in order to understand possible triggers to outbreaks of KD. This work provides future opportunities to leverage machine learning, including state-of-the-art deep architectures, to build predictive models of KD outbreaks, with the ultimate goal of early forecasting and intervention within a nascent global health early-warning system.

Diagnosis of coccidioidomycosis in a non-endemic area: Inference of the probable geographic area of an infection

BACKGROUND

Coccidioidomycosis is one of the most important endemic mycoses in Northern Mexico. However, diagnosing this disease can be challenging, particularly in patients who do not reside in endemic areas.

CASE REPORT

The case of a Mexican HIV+ patient who developed fever, general malaise, a severe cough, and dyspnea during a stay in Acapulco, Guerrero, Mexico, is presented. Since various diseases are endemic to the state of Guerrero, the doctors originally suspected that the patient had contracted influenza A (H1N1), Q fever, or tuberculosis. All the diagnostic tests for those diseases were negative. The patient had received numerous mosquito bites while staying in Acapulco, and a nodule had appeared on his right cheek. Therefore, malaria, cryptococcosis, and histoplasmosis were also suspected, but those infections were also ruled out through diagnostic tests. A direct microscopic examination was performed using KOH on a sample taken from the cheek nodule. The observation of spherules suggested the presence of a species of Coccidioides. The fungus was isolated, and its identity was confirmed by phenotypic and molecular methods. The geographic area in which the infection was likely acquired was identified by random amplified polymorphic DNA (RAPD) analysis. The results suggested a probable endogenous reactivation.

CONCLUSIONS

This clinical case illustrates the difficulties associated with diagnosing coccidioidomycosis in non-endemic areas.

Assessment of Vulnerability to Coccidioidomycosis in Arizona and California

Coccidioidomycosis is a fungal infection endemic to the southwestern United States, particularly Arizona and California. Its incidence has increased, potentially due in part to the effects of changing climatic variables on fungal growth and spore dissemination. This study aims to quantify the county-level vulnerability to coccidioidomycosis in Arizona and California and to assess the relationships between population vulnerability and climate variability. The variables representing exposure, sensitivity, and adaptive capacity were combined to calculate county level vulnerability indices. Three methods were used: (1) principal components analysis; (2) quartile weighting; and (3) percentile weighting. Two sets of indices, "unsupervised" and "supervised", were created. Each index was correlated with coccidioidomycosis incidence data from 2000-2014. The supervised percentile index had the highest correlation; it was then correlated with variability measures for temperature, precipitation, and drought. The supervised percentile index was significantly correlated (p < 0.05) with coccidioidomycosis incidence in both states. Moderate, positive significant associations (p < 0.05) were found between index scores and climate variability when both states were concurrently analyzed and when California was analyzed separately. This research adds to the body of knowledge that could be used to target interventions to vulnerable counties and provides support for the hypothesis that population vulnerability to coccidioidomycosis is associated with climate variability.

Large-Scale Land Development, Fugitive Dust, and Increased Coccidioidomycosis Incidence in the Antelope Valley of California, 1999-2014

Ongoing large-scale land development for renewable energy projects in the Antelope Valley, located in the Western Mojave Desert, has been blamed for increased fugitive dust emissions and coccidioidomycosis incidence among the general public in recent years. Soil samples were collected at six sites that were destined for solar farm construction and were analyzed for the presence of the soil-borne fungal pathogen Coccidioides immitis which is endemic to many areas of central and southern California. We used a modified culture-independent nested PCR approach to identify the pathogen in all soil samples and also compared the sampling sites in regard to soil physical and chemical parameters, degree of disturbance, and vegetation. Our results indicated the presence of C. immitis at four of the six sites, predominantly in non-disturbed soils of the Pond-Oban complex, which are characterized by an elevated pH and salt bush communities, but also in grassland characterized by different soil parameters and covered with native and non-native annuals. Overall, we were able to detect the pathogen in 40% of the soil samples (n = 42). Incidence of coccidioidomycosis in the Antelope Valley was positively correlated with land use and particulate matter in the air (PM10) (Pearson correlation coefficient >0.5). With the predicted population growth and ongoing large-scale disturbance of soil in the Antelope Valley in coming years, incidence of coccidioidomycosis will likely further increase if policy makers and land developers continue to ignore the risk of grading land without implementing long-term dust mitigation plans in Environmental Impact Reports.

Disseminated coccidioidomycosis presenting with intramedullary spinal cord abscesses: Management challenges

Coccidioides species are endemic to the southwestern United States and typically cause a mild or asymptomatic primary infection. In some instances, infection can disseminate and involve the central nervous system with meningitis being the most common manifestation. Non-osseous spinal cord involvement is exceedingly rare. We report a case of disseminated coccidioidomycosis in an otherwise healthy 20 year old man with diffuse leptomeningeal enhancement, cerebrospinal fluid findings suggestive of meningitis, and intramedullary spinal cord abscesses. Response to treatment occurred with prolonged systemic liposomal amphotericin B and voriconazole. An extended course of steroids was needed to blunt inflammation.

Antifungal therapeutics for dimorphic fungal pathogens

Dimorphic fungi cause several endemic mycoses which range from subclinical respiratory infections to life-threatening systemic disease. Pathogenic-phase cells of Histoplasma, Blastomyces, Paracoccidioides and Coccidioides escape elimination by the innate immune response with control ultimately requiring activation of cell-mediated immunity. Clinical management of disease relies primarily on antifungal compounds; however, dimorphic fungal pathogens create a number of challenges for antifungal drug therapy. In addition to the drug toxicity issues known for current antifungals, barriers to efficient drug treatment of dimorphic fungal infections include natural resistance to the echinocandins, residence of fungal cells within immune cells, the requirement for systemic delivery of drugs, prolonged treatment times, potential for latent infections, and lack of optimized standardized methodology for in vitro testing of drug susceptibilities. This review will highlight recent advances, current therapeutic options, and new compounds on the horizon for treating infections by dimorphic fungal pathogens.

Coccidioidomycosis osteomyelitis of the knee in a 23-year-old diabetic patient

Coccidioidomycosis is a pulmonary infection caused by the dimorphic fungi Coccidioides immitis and Coccidioidomycosis posadasii. This disease is endemic to the southwestern United States and has a predilection for immunocompromised patients. Diabetes mellitus has been shown to be a strong risk factor for acquiring this infection in these states. Most cases are asymptomatic or present with mild pulmonary symptoms. However, untreated pulmonary mycosis can lead to disseminated infection, most often involving meningitis, osteomyelitis, or skin and soft-tissue infections. When there is arthritis, the knee is the most common site of infection. We present a case of a 23-year-old male with longstanding, uncontrolled Type 1 diabetes mellitus who was found to have pulmonary coccidioidomycosis following diagnosis of coccidioidomycosis osteomyelitis of the knee.

The Changing Epidemiology of Coccidioidomycosis in Los Angeles (LA) County, California, 1973-2011

Coccidioidomycosis, also known as Valley Fever, is often thought of as an endemic disease of central California exclusive of Los Angeles County. The fungus that causes Valley Fever, Coccidioides spp., grows in previously undisturbed soil of semi-arid and arid environments of certain areas of the Americas. LA County has a few large areas with such environments, particularly the Antelope Valley which has been having substantial land development. Coccidioidomycosis that is both clinically- and laboratory-confirmed is a mandated reportable disease in LA County. Population surveillance data for 1973-2011 reveals an annual rate increase from 0.87 to 3.2 cases per 100,000 population (n = 61 to 306 annual cases). In 2004, case frequency started substantially increasing with notable epidemiologic changes such as a rising 2.1 to 5.7 male-to-female case ratio stabilizing to 1.4-2.2. Additionally, new building construction in Antelope Valley greatly rose in 2003 and displayed a strong correlation (R = 0.92, Pearson p<0.0001) with overall LA County incidence rates for 1996-2007. Of the 24 LA County health districts, 19 had a 100%-1500% increase in cases when comparing 2000-2003 to 2008-2011. Case residents of endemic areas had stronger odds of local exposures, but cases from areas not known to be endemic had greater mortality (14% versus 9%) with notably more deaths during 2008-2011. Compared to the 57 other California counties during 2001-2011, LA County had the third highest average annual number of cases and Antelope Valley had a higher incidence rate than all but six counties. With the large number of reported coccidioidomycosis cases, multi-agency and community partnering is recommended to develop effective education and prevention strategies to protect residents and travelers.

Distance from construction site and risk for coccidioidomycosis, Arizona, USA

Coccidioides spp. fungi, which are present in soil in the southwestern United States, can become airborne when the soil is disrupted, and humans who inhale the spores can become infected. In 2012, our institution in Maricopa County, Arizona, USA, began a building project requiring extensive excavation of soil. One year after construction began, we compared the acquisition of coccidioidomycosis in employees working adjacent to the construction site (campus A) with that of employees working 13 miles away (campus B). Initial testing indicated prior occult coccidioidal infection in 20 (11.4%) of 176 campus A employees and in 19 (13.6%) of 140 campus B employees (p = 0.55). At the 1-year follow-up, 3 (2.5%) of 120 employees from campus A and 8 (8.9%) of 90 from campus B had flow cytometric evidence of new coccidioidal infection (p = 0.04). The rate of coccidioidal acquisition differed significantly between campuses, but was not higher on the campus with construction.

A paradigm for the evaluation and management of spinal coccidioidomycosis

Background:

Coccidioidomycosis is a fungal infection that is endemic to parts of the Southwestern United States. When infection involves the spine, the treatment strategies can be challenging. We have devised a management protocol for spinal coccidioidomycosis based on a review of the literature and our experience.

Methods:

The electronic literature search of National Library of Medicine for publications from 1964 to 2014 was performed using the following keywords: Coccidioidomycosis and spine. The search yielded 24 papers. Treatment strategies were summarized into a treatment protocol.

Results:

A total of 164 cases of spinal coccidioidomycosis were identified, ranging in age from <10 to >80 years. Males (n = 131) and African-Americans (n = 79) were strikingly over-represented. Medical therapy: Once a diagnosis of spinal coccidioidomycosis is established, antifungal therapy should always be started. Antifungal therapy with amphotericin B or azoles like fluconazole. Medical therapy needs to be continued for many years and sometimes indefinitely to reduce disease recurrence or progression. Surgical management is indicated in cases with mechanical instability, neurologic deficit, medically intractable pain, or progression of infection despite antifungal therapy.

Conclusions:

This work provides a working protocol involving assessment and reassessment for the management of spinal coccidioidomycosis. Medical management with antifungal agents in some cases can provide satisfactory disease control. However, in patients with mechanical instability, neurologic deficit, medically intractable pain or disease progression disease control may only be achieved with surgical debridement and stabilization.

Diagnosis and initial management of musculoskeletal coccidioidomycosis in children

BACKGROUND

Coccidioidomycosis is an invasive fungal infection caused by the inhalation of aerosolized spores of Coccidioides spp., which reside in the arid soil of the southwestern United States and northern Mexico. Approximately two thirds of cases are asymptomatic, and the remainder usually present with mild flu-like symptoms. Dissemination of coccidioidomycosis is rare, and can lead to extrapulmonic diseases including meningitis, osteomyelitis, and skin and soft-tissue involvement. The purpose of this study is to report our experience with musculoskeletal coccidioidomycosis in children.

METHODS

This was a retrospective chart review of patients with musculoskeletal infection with Coccidioides spp. at a tertiary care pediatric hospital from 1997 to 2010, identified by a search of ICD-9 codes and hospital diagnoses. Demographic and clinical data were collected from medical records, including the age of the patient, sex, white blood cell count, immunocompetence, length of stay, location of involvement, and initial treatment. In total, 20 children were identified with musculoskeletal coccidioidomycosis. The mean age was 12.3 years (range, 2 to 17 y) at time of diagnosis. Diagnostic criteria included positive imaging tests (plain film+MRI), serologic positive titers, and/or biopsy with positive cultures.

RESULTS

The most common presenting symptom was bone pain (100%); only 3 (15%) patients had accompanying signs/symptoms of pulmonary infection. Only 2 (5%) patients had a white blood cell count >15×10/L (5%). Locations of infection included the foot (28%), knee (14%), spine (12%), forearm (10%), lower leg (6%), and other sites (30%). Fluconazole was the most common antifungal agent used (75%). Surgical intervention was required in 10 (50%) patients.

CONCLUSIONS

This is the first series that has described musculoskeletal coccidioidomycosis exclusively in children. This study suggests that the initial presentation of this disease can be nonspecific and difficult to recognize in children. Clinicians should consider this diagnosis when faced with a musculoskeletal infection in children from the southwestern United States and northern Mexico.

LEVEL OF EVIDENCE

IV (case series).

Surgical pathology of skeletal coccidioidomycosis: a clinical and histopathologic analysis of 25 cases

Skeletal coccidioidomycosis is a rare complication of pulmonary coccidioidomycosis that remains incompletely characterized, and its histopathologic features have not been systematically evaluated. All skeletal coccidioidal infections (2000 to 2012) were retrieved from the University of Arizona and Mayo Clinic in Arizona pathology archives. Clinical history and histologic features were reviewed. Among 25 patients (median age 40 y; 17 men), infections involved bones (2 cases), joints (6), or both (17), usually in the distal extremities (68%), especially the wrist (32%). History included previously documented coccidioidomycosis (13), autoimmune disease (8), diabetes (6), malignancy (4), and iatrogenic immunosuppression (10). Common symptoms (median 3 mo) included pain/arthralgia (21) and swelling (10). Cultures and serology were positive in 15 of 17 (88%) and 19 of 22 patients (86%), respectively. Treatment included surgical debridement(s) and chronic antifungal medication(s). Histologic review showed granulomas in all cases, ranging from poorly to well formed, with or without necrosis. Spherule density varied widely (mean 4.8/HPF; range <0.1 to 13.5/HPF). Composition of inflammatory infiltrates, degree of necrosis, and extent of fibrosis did not significantly differ between immunocompetent and immunocompromised patients. Eosinophils were only seen in one third of cases; when present, eosinophils were almost always rare. 10 patients experienced recurrent infection, 8 of whom were immunocompromised; the remaining patients recovered. In conclusion, distal extremities are the most common sites of skeletal coccidioidomycosis encountered by surgical pathologists. This condition is strongly associated with autoimmune disorders and immunosuppression. Spherules are sometimes rare, and multiple modalities including serology, culture, and histology may be required for diagnosis.

Beyond the superficial: Coccidioides immitis fungaemia in a man with fever, fatigue and skin nodules: a case of an emerging and evolving pathogen

Coccidioidomycosis is an insidious fungal disease, endemic to arid regions of the Americas, which is becoming more frequently recognised worldwide. While most infections resemble a mild respiratory illness, a subset of cases progress to severe pneumonia or systemic dissemination. Here, we describe a case of disseminated coccidioidomycosis in a 54-year-old immunocompetent African-American man with geographic and demographic risk factors for Coccidiodes acquisition who presented with 2 months of fevers, fatigue, weight loss and painful skin lesions. Blood count and serum chemistry studies initially demonstrated leukocytosis, anaemia, hyponatraemia and acute renal failure. Chest imaging revealed numerous small pulmonary nodules and skin biopsy, serological studies and blood cultures eventually confirmed disseminated infection with Coccidioides immitis. This case highlights important features regarding the risk factors, spectrum of clinical findings, evaluation and treatment of coccidioidomycosis relevant to providers in endemic areas and throughout the world.

Primary cutaneous coccidioidomycosis: first imported case in north India

Coccidioidomycosis is a fungal disease found only in the Western Hemisphere. In recent years, the incidence of the disease has increased in California and Arizona, which may be partially due to the rapid immigration of previously unexposed persons from states outside the endemic areas. The disease in the nonendemic areas is usually imported. Determining a history of exposure is critical for performing the diagnosis of coccidioidomycosis in these cases. Histopathological examination is the key to the diagnosis when fungal culture and molecular studies are not available. We hereby report an imported case of cutaneous coccidioidomycosis, which to the best of our knowledge is the first case report from North India.

Valley fever: danger lurking in a dust cloud

Coccidioides immitis and Coccidioides posadasii contribute to the development of Valley Fever. The ability of these fungal pathogens to evade the host immune system creates difficulty in recognition and treatment of this debilitating infection. In this review, we describe the current knowledge of Valley Fever and approaches to improve prevention, detection, and treatment.