Coccidioidomycosis in non-endemic areas: a case series

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.

Coccidioidomycosis where you least expect it

An elderly man without history of travel presented with complaints of intermittent fever for 2 months, cough with scanty expectoration for 15 days and history of weight loss of 5 kg in 1 year. The chest X-ray and CT scan of the thorax showed dispersed centrilobular nodules and patchy subpleural consolidation in both lungs with mediastinal lymphadenopathy. He underwent bronchoscopy and bronchoalveolar lavage culture grew Pseudomonas aeruginosa He was prescribed antibiotics based on culture sensitivity; however, patient continued to have symptoms. All relevant blood investigations were within normal limits. He underwent CT-guided biopsy of the right lung lesion during which clearing of the radio-opacities present in the initial CT scan and appearance of fresh lesions in different locations were observed. Migratory shadows were suspected. Fine-needle aspiration cytology showed features suggestive of coccidioidomycosis for which antifungals were started. After 1 month, he improved symptomatically and chest X-ray showed clearance of shadows.

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.

Endemic fungal infections in solid organ transplant recipients-Guidelines from the American Society of Transplantation Infectious Diseases Community of Practice

These updated guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation review the diagnosis, prevention and management of blastomycosis, histoplasmosis, and coccidioidomycosis in the pre- and post-transplant period. Though each of these endemic fungal infections has unique epidemiology and clinical manifestations, they all share a predilection for primary pulmonary infection and may cause disseminated infection, particularly in immunocompromised hosts. Culture remains the gold standard for definitive diagnosis, but more rapid diagnosis may be achieved with direct visualization of organisms from clinical specimens and antigen-based enzyme immunoassay assays. Serology is of limited utility in transplant recipients. The mainstay of treatment for severe infections remains liposomal amphotericin followed by a step-down azole therapy. Cases of mild to moderate severity with no CNS involvement may be treated with azole therapy alone. The newer generation azoles provide additional treatment options, but supported currently with limited clinical efficacy data. Azole therapy in transplant recipients presents a unique challenge owing to the drug-drug interactions with immunosuppressant agents. Therapeutic drug monitoring of azole levels is an essential component of effective and safe therapy. Infection prevention centers around minimizing epidemiological exposures, early clinical recognition, and azole prophylaxis in selected individuals.

Enhanced Surveillance for Coccidioidomycosis, 14 US States, 2016

Although coccidioidomycosis in Arizona and California has been well-characterized, much remains unknown about its epidemiology in states where it is not highly endemic. We conducted enhanced surveillance in 14 such states in 2016 by identifying cases according to the Council of State and Territorial Epidemiologists case definition and interviewing patients about their demographic characteristics, clinical features, and exposures. Among 186 patients, median time from seeking healthcare to diagnosis was 38 days (range 1–1,654 days); 70% had another condition diagnosed before coccidioidomycosis testing occurred (of whom 83% were prescribed antibacterial medications); 43% were hospitalized; and 29% had culture-positive coccidioidomycosis. Most (83%) patients from nonendemic states had traveled to a coccidioidomycosis-endemic area. Coccidioidomycosis can cause severe disease in residents of non–highly endemic states, a finding consistent with previous studies in Arizona, and less severe cases likely go undiagnosed or unreported. Improved coccidioidomycosis awareness in non–highly endemic areas is needed.

Epidemiological Characterization of Imported Systemic Mycoses Occurred in Korea

OBJECTIVES

Imported systemic mycoses is a severe fungal infection that can cause diseases in healthy people. However, there is a serious lack of epidemiological data about imported systemic mycoses. Therefore, an epidemiological characterization of imported systemic mycoses in Korea was performed.

METHODS

We collected health insurance data between 2008 and 2012 from the Health Insurance Corporation and analyzed the data to determine the prevalence and treatment management of imported systemic mycoses.

RESULTS

The prevalence of imported systemic mycoses between 2008 and 2012 increased slowly by 0.49/100,000 to 0.53/100,000 persons. The prevalence of coccidioidomycosis increased from 0.28/100,000 in 2008 to 0.36/100,000 persons in 2012. A mean of 229.6 cases occurred each year. Children and the elderly showed higher prevalence than adults in the 20- to 59-year-old age group. The rate of infection according to region ranged from 0.18/100,000 persons in Ulsan, to 0.59/100,000 persons in Gyeonggi. The prevalence in females was higher than that in males. Inpatient treatment was 3.3% (38 cases), with 96.7% treated as outpatients. Hospitalizations cost 272.7 million won and outpatient treatments cost 111.7 million won. The treatment cost for coccidioidomycosis from 2008 to 2012 was 330.9 million won, with personal charges of 79.2 million won and insurance charges of 251.7 million won. Most of the expenses for the coccidioidomycosis treatment were for inpatient treatment.

CONCLUSION

The results in this study may be a useful resource for determining the changes in the trend of imported systemic mycoses.

Coccidioidomycosis: Imported and possible domestic cases in China: A case report and review, 1958-2017

We report a case of imported pulmonary coccidioidomycosis caused by Coccidioides posadasii in a patient who was misdiagnosed as tuberculosis and mistreated with antituberculosis medications for 18 months. The symptoms were not relieved until antifungal treatment was started. An extensive review of the coccidioidomycosis cases occurring in China reveals 38 cases, 16 of which had no associated history of travel to any traditional endemic areas. We speculate that some factors may drive Coccidioides spp. transference to China, which then causes those domestic infections. Moreover, we indicate the first, to the best of our knowledge, possible endemic areas in China.

Coccidioidomycosis causing osteomyelitis of the hand in an immunocompetent patient

Coccidioidomycosis osteomyelitis is a rare entity considered even more rare when identified in the immunocompetent patient. In non-endemic areas, the diagnosis of a fungus-causing osteomyelitis is often delayed or overlooked. This results in delayed or inappropriate treatment. We present the case of a 35-year-old immunocompetent male immigrant from India who was ultimately diagnosed as having Coccidioidomycosis immitis osteomyelitis of his ring finger metacarpal. His initial surgery included drainage and bacterial cultures only. When he failed to improve, he presented for a second opinion. The patient's origin and travel history coupled with the appearance of rapid bone destruction on plain radiographs prompted a second operation for tissue biopsy and culture for bacteria, fungus, and mycobacteria cultures. This case highlights the importance of a thorough clinical history in deriving an appropriate differential diagnosis prior to surgical intervention.

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.

Genetic analysis of the endemic fungal pathogens Coccidioides posadasii and Coccidioides immitis in Mexico

Coccidioidomycosis (CM) is a mycotic disease that affects mammals, including humans. Official data relative to CM in Mexico has not been collected since 1995, thus its prevalence remains unknown. The objectives of this study were to identify the predominant Coccidioides species in Mexico, infer their current geographical distribution and explore the correlation between species and clinical presentation. We collected 154 strains, which were cultured, inactivated, and processed for DNA extraction. Nine microsatellite loci, the Ag2/PRA gene and Umeyama Region were amplified from each isolate. To infer the current geographical distribution of Coccidioides spp. and to establish a correlation between genotype and clinical presentation, we evaluated genetic population structure under the following grouping criteria: putative origin and clinical presentation records. Microsatellite analysis showed that 82% of the isolates corresponded to C. posadasii and 18% were C. immitis. The species identification results obtained using Umeyama region, Ag2/PRA, and microsatellites of five of the isolates were inconsistent with the data collected for the remaining isolates. C. posadasii strains were found primarily in the northeastern region and C. immitis in the northwestern region. However, there was no relationship between clinical presentation and Coccidioides species. The molecular markers used in this study proved to have a high power of resolution to identify the Coccidioides species recovered in culture. While we found C. posadasii to be the most abundant species in Mexico, more detailed clinical records are needed in order to obtain more accurate information about the infections in specific geographical locations.

Coccidioidomycosis: epidemiology

Coccidioidomycosis consists of a spectrum of disease, ranging from a mild, self-limited, febrile illness to severe, life-threatening infection. It is caused by the soil-dwelling fungi, Coccidioides immitis and C. posadasii, which are present in diverse endemic areas. Climate changes and environmental factors affect the Coccidioides lifecycle and influence infection rates. The incidence of coccidioidomycosis has risen substantially over the past two decades. The vast majority of Coccidioides infections occur in the endemic zones, such as California, Arizona, Mexico, and Central America. Infections occurring outside those zones appear to be increasingly common, and pose unique clinical and public health challenges. It has long been known that elderly persons, pregnant women, and members of certain ethnic groups are at risk for severe or disseminated coccidioidomycosis. In recent years, it has become evident that persons with immunodeficiency diseases, diabetics, transplant recipients, and prisoners are also particularly vulnerable.

A case study of imported pulmonary coccidioidomycosis

Coccidioidomycosis is an endemic disease of the Western hemisphere. The cases in non-endemic areas are mostly imported. Determining a history of exposure is critical for performing the diagnosis of coccidioidomycosis, especially for cases occurring in a non-endemic area. In this study, a 71-year-old Chinese male presented to our hospital with chronic cough and malaise, and was found to have a mass in the middle lobe of right lung. He had been visiting Arizona, USA for four months before admission. Pulmonary coccidioidomycosis was confirmed by the results of histopathological examination after lobectomy. Typical microscopic features of Coccidioides are definitely diagnostic, but need be differentiated from other budding yeast infection or carcinoma histopathologically.

What's Behind the Increasing Rates of Coccidioidomycosis in Arizona and California?

The number of cases of symptomatic coccidioidomycosis reported in the endemic regions of California and Arizona has increased over the past two decades. In California, the southern San Joaquin Valley has seen a dramatic increase, with rates of symptomatic illness of more than 150 per 100,000 of population in Kern County. In Arizona, almost 5,000 cases are now reported yearly. In contrast to California, the coccidioidal endemic region in Arizona is also the most populous region of the state, and Arizona now accounts for 60% of all cases reported in the United States. Reasons for these increases appear to be multifactorial. Possible etiologies include climate change, changes in local exposure, an increase in the number of individuals susceptible to infection living in the endemic region, and increased testing and reporting. None of these factors are mutually exclusive and none has been clearly established as the etiology for the increase.

Coccidioidomycosis and tuberculosis coinfection at a tuberculosis hospital: clinical features and literature review

Tuberculosis (TB) and coccidioidomycosis can have similar clinical and radiologic presentations but require different treatments. Coinfection with TB and Coccidioides immitis is uncommonly reported and may be underdiagnosed in endemic areas.We performed a retrospective review of the medical records of all patients admitted to a TB referral hospital between 1995 and 2007, and selected all cases of TB and coccidioidomycosis coinfection in patients aged 18 years or older. All admitted patients had a diagnosis of TB and had sputum cultures for both pathogens. We reviewed clinical, laboratory, and radiologic features of the cases, and noted antimicrobial treatments received and outcomes.We identified 9 patients, of whom 7 (78%) were Hispanic. Most patients were male (8/9, 89%), and all were diagnosed with coccidioidomycosis after TB. Three (33%) patients had drug-resistant TB. Six patients had culture-positive TB at the time of the double diagnosis, and 2 patients developed active coccidioidomycosis during their hospital stay. Only 1 had human immunodeficiency virus/acquired immunodeficiency syndrome (HIV-AIDS) (CD4 count, 20 cells/mm). All but 2 patients were treated with antifungal agents. Two patients died, 1 of whom had AIDS. Radiologic studies were unable to distinguish between TB and coccidioidomycosis, except for a patient who developed a new air-fluid level in a previously stable cavity.TB and coccidioidomycosis coinfection should be suspected in coccidioidomycosis-endemic regions among patients with TB who fail to improve clinically or radiologically despite adequate, culture-directed therapy.

Pulmonary Coccidioides nodule in a Swiss patient with chronic lymphatic leukaemia

The dimorphic fungus Coccidioides immitis, causative agent of coccidioidomycosis, is endemic in semi-arid regions of the Americas. The disease is rarely encountered in Europe. We describe the case of a 61-year-old Swiss patient with chronic lymphatic leukaemia who was eventually diagnosed with an initially unnoticed pulmonary coccidioidomycosis.

Fungal Infections

The incidence of invasive fungal infections has increased dramatically over the past two decades, mostly due to an increase in the number of immunocompromised patients.1–4 Patients who undergo chemotherapy for a variety of diseases, patients with organ transplants, and patients with the acquired immune deficiency syndrome have contributed most to the increase in fungal infections.5 The actual incidence of invasive fungal infections in transplant patients ranges from 15% to 25% in bone marrow transplant recipients to 5% to 42% in solid organ transplant recipients.6,7 The most frequently encountered are Aspergillus species, followed by Cryptococcus and Candida species. Fungal infections are also associated with a higher mortality than either bacterial or viral infections in these patient populations. This is because of the limited number of available therapies, dose-limiting toxicities of the antifungal drugs, fewer symptoms due to lack of inflammatory response, and the lack of sensitive tests to aid in the diagnosis of invasive fungal infections.1 A study of patients with fungal infections admitted to a university-affiliated hospital indicated that community-acquired infections are becoming a serious problem; 67% of the 140 patients had community-acquired fungal pneumonia.8

Coccidioidomycosis pneumonia in a nonendemic area associated with infliximab

Tumor necrosis factor (TNF) inhibitors, such as infliximab, are highly effective in the management of rheumatoid arthritis; however, these agents are associated with an increased risk of infectious complications. Individuals developing coccidiomycosis pneumonia frequently acquire this while residing in endemic regions. We present a patient with rheumatoid arthritis treated with infliximab who developed acute respiratory distress syndrome (ARDS) from coccidiomycosis pneumonia while residing in a non-endemic region near the Texas-Louisiana border and was successfully treated with antifungal therapy. The source for coccidiomycosis was suspected to be from inhalation of pulverized rock dust imported from Arizona. Patients treated with TNF inhibitors may acquire coccidiomycosis infection through fomite dust exposure.

Fomite-transmitted coccidioidomycosis in an immunocompromised child

An unusual, nonendemic case of fomite-transmitted, disseminated coccidioidomycosis in a neutropenic 3-year-old boy is presented. Accurate diagnosis of coccidioidomycosis hinges on recognition of host risk factors, clinical signs and symptoms, and effective implementation of diagnostic studies. Timely diagnosis and treatment is critical for improved morbidity and mortality in the pediatric oncology population.

Expanding understanding of epidemiology of coccidioidomycosis in the Western hemisphere

Coccidioidomycosis is a disease of both national and worldwide importance that is most often diagnosed in nonendemic regions. The endemic region for Coccidioides spp. lies exclusively in the Western Hemisphere. Coccidioides spp. has long been identified in semiarid areas of the United States and Mexico, and endemic foci have been described in areas of Central and South America. Infection is usually the result of activities that cause the fungus to become airborne and inhaled by a susceptible host. Underlying medical diseases that affect T cell function are known to increase the risk of disseminated disease and include human immunodeficiency virus, cancer, and disease processes requiring transplantation and its subsequent immunosuppressive agents. In recent years the incidence of the coccidioidomycosis has increased in California and Arizona, which may be partially due to the massive migration of Americans to the Sunbelt states. To date the highest number of cases reported in Arizona was in 2004, when a total of 3,665 cases of coccidioidomycosis was reported, representing a 281% increase since 1997. Statistics on the prevalence and incidence of coccidioidomycosis in Latin America either are fragmentary or simply are not available.

The population biology of coccidioides: epidemiologic implications for disease outbreaks

Studies of field- and patient-derived isolates conducted over the past 75 years have provided a general picture of the population structure of Coccidioides, the cause of coccidioidomycosis. Premolecular studies provided a general outline of the geographical range, epidemiology and distribution of the fungus. Recent studies based on molecular markers have demonstrated that the genus is comprised of two genetically diverse, and genetically isolated, species: Coccidioides immitis and C. posadasii. Both species are composed of biogeographically distinct populations. Structure for two of these populations (C. immitis from central California, and C. posadasii from southern Arizona) indicates that frequent genetic recombination occurs within the entire geographic range of each population, even though sex has never been observed in the genus. Outbreaks of coccidioidomycosis are not the result of the spread of a single clonal isolate, but are caused by a diversity of genotypes. Although it is now possible to match patient isolates to populations, the lack of apparent structure within each population and the current paucity of environmental isolates limit map-based epidemiological approaches to understanding outbreaks. Therefore, a comprehensive database comprised of soil-derived isolates from across the biogeographic range of Coccidioides will improve the utility of this approach. Appropriate collection of environmental isolates will assist the investigation of remaining questions regarding the population biology of Coccidioides. The comparative genomics of representative genotypes from both species and all populations of Coccidioides will provide a thorough set of genetic markers in order to resolve the population genetics of this pathogenic fungus.

Coccidioidomycosis: a review and update

Coccidioidomycosis occurs in arid and semi-arid regions of the New World from the western United States to Argentina. Highly endemic areas are present in the southwest United States. Coccidioides species live in the soil and produce pulmonary infection via airborne arthroconidia. The skin may be involved by dissemination of the infection, or by reactive eruptions, such as a generalized exanthem or erythema nodosum. Interstitial granulomatous dermatitis and Sweet's syndrome have recently been recognized as additional reactive signs of the infection. Coccidioidomycosis is a "great imitator" with protean manifestations. Cutaneous findings may be helpful clues in the diagnosis of this increasingly important disease.

Unusual Case of Pyopneumothorax in Tennessee

Rupture of a coccidioidal pulmonary cavity with subsequent pyopneumothorax is a rare clinical event, even in areas endemic for coccidioidomycosis. Our encounter with a patient diagnosed with this condition in northeast Tennessee serves notice to clinicians that coccidioidomycosis is indeed a traveling fungal disease, and practitioners must be alert to common and uncommon manifestations of infection associated with this fungus. A literature review pertaining to coccidioidal pyopneumothorax revealed that patients usually present with a recent onset of chest pain. Serologic testing and pleural fluid culture are highly useful, and management includes surgical intervention with or without antifungal therapy.

Coccidioidomycosis diagnosed in South Carolina

Primary care physicians in the Eastern United States rarely consider coccidioidomycosis in the differential diagnosis of pulmonary infections or febrile illnesses. However, the mobility of the population mandates consideration of this diagnosis, particularly in patients with fever and cough that do not resolve rapidly and in patients with adenopathy on chest radiography. In this report, we describe two unrelated cases encountered during a single week in a South Carolina internal medicine practice. These cases highlight the importance of obtaining travel histories from patients with atypical pulmonary infections. Early consideration of coccidioidomycosis confers several benefits, including allaying patient anxiety by more timely diagnosis, minimizing the empiric use of antibiotics, and reducing the need for extensive and possibly invasive diagnostic testing.

Coccidioidomycosis: host response and vaccine development

Coccidioidomycosis is caused by the dimorphic fungi in the genus Coccidioides. These fungi live as mycelia in the soil of desert areas of the American Southwest, and when the infectious spores, the arthroconidia, are inhaled, they convert into the parasitic spherule/endospore phase. Most infections are mild, but these organisms are frank pathogens and can cause severe lethal disease in fully immunocompetent individuals. While there is increased risk of disseminated disease in certain racial groups and immunocompromised persons, the fact that there are hosts who contain the initial infection and exhibit long-term immunity to reinfection supports the hypothesis that a vaccine against these pathogens is feasible. Multiple studies have shown that protective immunity against primary disease is associated with T-helper 1 (Th-1)-associated immune responses. The single best vaccine in animal models, formalin-killed spherules (FKS), was tested in a human trial but was not found to be significantly protective. This result has prompted studies to better define immunodominant Coccidioides antigen with the thought that a subunit vaccine would be protective. These efforts have defined multiple candidates, but the single best individual immunogen is the protein termed antigen 2/proline-rich antigen (Ag2/PRA). Studies in multiple laboratories have shown that Ag2/PRA as both protein and genetic vaccines provides significant protection against mice challenged systemically with Coccidioides. Unfortunately, compared to the FKS vaccine, it is significantly less protective as measured by both assays of reduction in fungal CFU and assays of survival. The capacity of Ag2/PRA to induce only partial protection was emphasized when animals were challenged intranasally. Thus, there is a need to define new candidates to create a multivalent vaccine to increase the effectiveness of Ag2/PRA. Efforts of genomic screening using expression library immunization or bioinformatic approaches to identify new candidates have revealed at least two new protective proteins, expression library immunization antigen 1 (ELI-Ag1) and a beta-1,3-glucanosyltransferase (GEL-1). In addition, previously discovered antigens such as Coccidioides-specific antigen (CSA) should be evaluated in assays of protection. While studies have yet to be completed with combinations of the current candidates, the hypothesis is that with increased numbers of candidates in a multivalent vaccine, there will be increased protection. As the genome sequences of the two Coccidioides strains which are under way are completed and annotated, the effort to find new candidates can increase to provide a complete genomic scan for immunodominant proteins. Thus, much progress has been made in the discovery of subunit vaccine candidates against Coccidioides and there are several candidates showing modest levels of protection, but for complete protection against pulmonary challenge we need to continue the search for additional candidates.

Posttransplantation disseminated coccidioidomycosis acquired from donor lungs

A North Carolinian developed fatal coccidioidomycosis immediately after bilateral lung transplantation. The donor had previously traveled to Mexico, and the recipient had no travel history to an area where Coccidioides immitis is endemic. Immunosuppressive therapy of the transplant recipient likely reactivated latent Coccidioides infection in the donor lungs, leading to posttransplant coccidioidomycosis.

Coccidioidomycosis: a descriptive survey of a reemerging disease. Clinical characteristics and current controversies

Coccidioidomycosis is a fungal disease with protean manifestations endemic to the Lower Sonoran Life Zone, which includes the hot deserts of the southwestern United States and areas of Mexico. Two hundred and twenty-three patients were found to have coccidioidomycosis at our institution from 1994-2002, the largest reported cohort of coccidioidomycosis patients since the 1950s. Of these patients, 58% presented with isolated pulmonary disease, 14% had high (>1:16) complement fixation titers without clear evidence of dissemination, 22% had definite disseminated disease, and 5% had unclassified disease. Enzyme immunoassay was a reliable diagnostic tool in those with symptomatic disease, but had a low specificity in those who were asymptomatic. Complement fixation titers of > or =1:16 were associated with dissemination to bone or skin but were not helpful in evaluating central nervous system disease. Thirteen percent of patients with high complement fixation titers (>1:16) without clear evidence of dissemination on presentation and 7% of those with isolated pulmonary disease eventually progressed to disseminated disease; 30% of Filipino patients with pulmonary disease progressed to disseminated disease. Nonwhite race was a predictor for dissemination; African American patients more often developed disseminated bony disease while Filipinos were more likely to develop cutaneous or central nervous system disease. Relapse of disseminated coccidioidomycosis occurred in 24% of patients; the risk was highest (71%) among those with central nervous system disease. Azole therapy was generally inferior to amphotericin B in disseminated disease. Predictors of permanent disability included African American or Filipino race, central nervous system disease, and bony disease.

A recombinant beta-1,3-glucanosyltransferase homolog of Coccidioides posadasii protects mice against coccidioidomycosis

Coccidioides posadasii is a fungal respiratory pathogen which is responsible for recurrent epidemics of San Joaquin Valley fever (coccidioidomycosis) in desert regions of the southwestern United States. Numerous studies have revealed that the cell wall of the parasitic phase of the fungus is a reservoir of immunoreactive macromolecules and a potential source of a vaccine against this mycosis. A 495-bp fragment of a C. posadasii gene which encodes a putative wall-associated, glycosylphosphatidylinositol (GPI)-anchored beta-1,3-glucanosyltransferase was identified by computational analysis of the partially sequenced genome of this pathogen. The translated, full-length gene (GEL1) showed high sequence homology to a reported beta-1,3-glucanosyltransferase of Aspergillus fumigatus (70% identity, 90% similarity) and was selected for further study. The GEL1 mRNA of C. posadasii was detected at the highest level during the endosporulation stage of the parasitic cycle, and the mature protein was immunolocalized to the surface of endospores. BALB/c or C57BL/6 mice were immunized subcutaneously with the bacterium-expressed recombinant protein (rGel1p) to evaluate its protective efficacy against a lethal challenge of C. posadasii by either the intraperitoneal or intranasal route. In both cases, rGel1p-immune mice infected with the pathogen showed a significant reduction in fungal burden and increased survival compared to nonimmune mice. The recombinant beta-1,3-glucanosyltransferase is a valuable addition to an arsenal of immunoreactive proteins which could be incorporated into a human vaccine against coccidioidomycosis.

Fungal infections among returning travelers

Endemic mycoses, such as histoplasmosis, coccidioidomycosis, and penicilliosis, have emerged as important health threats among travelers to regions of the world where these infections are endemic. Travelers have developed fungal infections as a result of a wide range of recreational and work activities, many of which have involved well-recognized risk factors for these diseases. In some instances, infections have been acquired during short trips, whereas, in other instances, infection has been acquired during a longer period of residence in an area where the infection is endemic. Travelers need to be made aware of the risks of acquiring mycotic diseases when visiting such regions. Health care providers need to consider these infections in their differential diagnosis among returning travelers with respiratory illness and should be familiar with the treatment and prevention of these diseases.

Recent advances in the epidemiology, prevention, diagnosis, and treatment of fungal pneumonia

Although pneumonia caused by fungi is not a common occurrence in the general population, disease in an enlarging immunocompromised population is encountered with increasing frequency. Fungal pneumonias are most frequently caused by Aspergillus spp., dimorphic fungi and Cryptococcus neoformans. Recent studies have identified risk factors of thrombocytopenia, environmental events (such as construction or renovation) and immunosuppressive drug therapies as being specific risk factors for invasive fungal disease in select patient populations. Diagnostic strategies to detect circulating antigens and polymerase chain reaction based detection systems have been explored to improve identification prior to the progressive advanced disease. Advances in prophylactic strategies include increased use of aerosolized formulations of amphotericin B, usually in conjunction with new and old systemic antifungal agents. Despite recent published guidelines for treatment of fungal pneumonia based on etiology, mortality remains high in some infections with advanced disease. Caspofungin, a new echinocandin antifungal, has recently been approved by the US Food and Drug Administration for the treatment of invasive Aspergillus infections in patients unresponsive to or unable to receive amphotericin B. A triazole antifungal, voriconazole, has shown promise in phase III clinical trials in patients with refractory fungal infections and is expected to be available in early 2002. Other echinocandin and triazole antifungals are under development in attempts to provide improved effective therapy for fungal pneumonia.