Constrictive pericarditis secondary to Coccidioides immitis infection in a dog

Development of a rapid lateral flow assay for detection of anti-coccidioidal antibodies

Coccidioides spp. are dimorphic fungi that are capable of infecting human and non-human mammals and can cause diverse manifestations of coccidioidomycosis or Valley fever (VF). In combination with clinical symptoms and radiographic findings, antibody-based diagnostic tests are often used to diagnose and monitor patients with VF. Chitinase 1 (CTS1) has previously been identified as the seroreactive antigen used in these diagnostic assays to detect anticoccidial IgG. Here, an indirect enzyme-linked immunosorbent assay to detect IgG to CTS1 demonstrated 165 of 178 (92.7%) patients with a positive result by immunodiffusion (ID) and/or complement fixation (CF) had antibodies to the single antigen CTS1. We then developed a rapid antibody lateral flow assay (LFA) to detect anti-CTS1 antibodies. Out of 143 samples tested, the LFA showed 92.9% positive percent agreement [95% confidence interval (CI), 84.3%-96.9%] and 97.7% negative percent agreement (95% CI, 87.9%-99.6%) with ID and CF assays. Serum or plasma from canines, macaques, and dolphins was also tested by the CTS1 LFA. Test line densities of the CTS1 LFA correlated in a linear manner with the reported CF and ID titers for human and non-human samples, respectively. This 10-min point-of-care test for the rapid detection of anti-coccidioidal antibodies could help to inform healthcare providers in real-time, potentially improving the efficiency of healthcare delivery.

Systematic review of the treatment options for pericardial effusions in dogs

OBJECTIVE

To evaluate the evidence for the conservative and surgical management of pericardial effusions for neoplastic and idiopathic etiologies in dogs.

STUDY DESIGN

Systematic review.

SAMPLE POPULATION

Peer-reviewed English-language articles describing the treatment and outcome of naturally occurring pericardial effusion in domestic dogs.

METHODS

A literature search was performed with PubMed, Cab Abstracts, Scopus, and Agricola in August 2019 for articles describing pericardial effusion treatment in dogs. Inclusion criteria were applied, and articles were evaluated for reported outcome and level of evidence by using The Oxford 2011 Levels of Evidence, a previously described hierarchical system, and GRADE (Grading of Recommendations, Assessment, Development and Evaluation).

RESULTS

One hundred eight of the 641 unique articles that were identified and evaluated met inclusion criteria. Most articles included were case studies (68.2%) or retrospective case series (25.2%), with all articles providing a low level of evidence. The articles had inconsistent inclusion criteria, outcome measures, and follow-up, making comparison of outcomes difficult.

CONCLUSION

Because of the low quality of evidence of the studies included in this systematic review and the variability of the outcomes, there is not sufficient evidence to recommend one treatment option rather than another.

CLINICAL SIGNIFICANCE

There is a requirement for higher quality evidence such as randomized controlled trials and prospective comparative cohort studies. Standardization of outcome measures reported for each treatment option and disease process studied will allow for better comparison of outcomes between studies.

The Causes of Canine Myocarditis and Myocardial Fibrosis Are Elusive by Targeted Molecular Testing: Retrospective Analysis and Literature Review

Myocarditis can cause death or permanent heart damage. As epidemiologic and etiopathologic data for canine myocarditis are lacking, we performed a retrospective study using nucleic acid extracted from archived (2007 to 2015) tissues from myocarditis cases and control dogs without myocardial lesions. Heart tissue from pediatric/juvenile and adult dogs was tested with a comprehensive panel of conventional and real-time polymerase chain reaction (PCR) assays targeting recognized agents of canine myocarditis based on a literature review and informed by the comparative epidemiology of human myocarditis. The PCR screen, which included canine parvovirus 2 (CPV-2), canine distemper virus, canine herpesvirus, Borrelia spp, West Nile virus, adenovirus, parainfluenza virus, pneumovirus, respiratory coronavirus, influenza virus, Bartonella spp, Rickettsia spp, Mycoplasma spp, and Neospora caninum, did not detect agents in 35 of 66 cases (53%; 95% confidence interval [CI], 41%-65%) and was frequently negative in adults (21/26); by comparison, agents were not detected in 27 of 57 controls (47%; 95% CI, 35%-60%). Canine distemper virus, herpesvirus, adenovirus, coronavirus, parainfluenza virus, Mycoplasma haemocanis, and N. caninum were occasionally detected in both cases and controls; thus, PCR detection was not considered to indicate causation. We previously reported that CPV-2 continues to be associated with myocarditis in young dogs despite widespread vaccination; in adults, CPV-2 was detected in 2 of 26 cases and 4 of 22 controls. As several agents were similarly detected in cases and controls, it is unclear if these are cardiopathogenic, incidental, or latent. West Nile virus was detected at the analytic limit in 1 adult case. We did not detect Borrelia spp, Bartonella spp, Rickettsia spp, or influenza A virus in the myocarditis cases. These data demonstrate the limitations of current targeted diagnostic tests and the need for additional research to identify unknown agents and develop testing strategies for canine myocarditis.

Canine leishmaniasis associated with pericardial effusion in a 4-year-old dog

A 4-year-old crossbreed dog presented with a two-day history of lethargy and abdominal effusion. Physical examination and echocardiography revealed pericardial effusion with cardiac tamponade. Pericardiocentesis was performed. Intracytoplasmic Leishmania amastigotes were found on cytological examination of the pericardial fluid. The animal was treated with N-methylglucamine antimoniate and allopurinol. After an initial favorable response, cardiac tamponade reoccurred one month later. The dog died during a pericardiectomy four months after the initial diagnosis. Histology confirmed the presence of chronic pericarditis. The presence of Leishmania amastigotes on cytological examination of pericardial effusion suggests a possible association between canine leishmaniasis and chronic pericarditis. This finding also supports the importance of cytological examination of pericardial fluid in areas endemic for canine leishmaniasis.

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.

Therapy of Non-Dermatophytic Mycoses in Animals

This review focuses on aspects of antimycotic therapy specific to veterinary medicine. In the first part, drug availability, limited mostly by economic consideration but also by clinical applicability and specific adverse effects, is described for polyenes, 5 fluorocytosine, azoles, echinocandins and terbinafine. In the second part, current knowledge and experience in the treatment of selected fungal infections are overviewed. These mycoses include disseminated mold infections in small animals (dogs and cats) and avian species, upper respiratory tract infections of small animals (sino-nasal and sino-orbital aspergillosis) and horses (guttural pouch mycosis), eumycetoma, infections caused by dimorphic fungi, (blastomycosis, histoplasmosis, coccidioidomycosis, paracoccidioidomycosis and sporothrichosis) and by yeasts and yeast-like microorganism (Cryptococcus spp. and Malassezia pachydermatis).

Evaluation of Pericardial Effusion in Dogs and Successful Treatment Using a Hemodialysis Fistula Needle: A Retrospective Study

The aim of this retrospective study was to assess epidemiology and echocardiographic findings of pericardial effusion in canine patients and to determine the clinical usefulness and safety of a new pericardiocentesis technique, using a "fistula needle" for hemodialysis. A database of 5304 dogs of different breeds, age, gender, type, and severity of the cardiac disease, referred for a specialist cardiology and echocardiographic examination from 2009-2016, was reviewed. All the dogs were subjected to echocardiography; when possible and required, an echo-guided pericardiocentesis was performed by mean of a 17G "fistula needle" commonly used for hemodialysis. Complete echocardiography was repeated at the end of each pericardiocentesis. Pericardial effusion was identified by echocardiography in 91 dogs (1.71%), 20 were female (21.98%) and 71 were male (78.02%). PE caused cardiac tamponade in 38/91 cases (41.76%). A clear evidence of a neoplasm was found in 33 cases (36.26%). In 32 cases (35.16%) severe degenerative mitral and tricuspid valve disease was detected as the cause of the pericardial effusion. Echo-guided pericardiocentesis was performed in 28 cases (30.77%) with cardiac tamponade. No adverse effects were found in any of the patients during the 48 hours of follow up after pericardiocentesis. This study showed the high incidence of pericardial effusion due to severe bilateral degenerative valve disease in adult to elderly dogs of different breeds. Moreover, the use of a "fistula needle" for pericardiocentesis in dogs showed no adverse effects.

The habitat of Coccidioides spp. and the role of animals as reservoirs and disseminators in nature

BACKGROUND

Coccidioidomycosis, a potentially fatal fungal infection, is considered an emergent mycotic disease because of the increased incidence of fungal infections registered over recent years. Infection occurs through the inhalation of arthroconidia from two main species of Coccidioides: Coccidioides immitis and C. posadasii, which are both endemic to arid and semi-arid regions of North America. Coccidioides species not only infect humans but can also infect other mammals (land, aquatic, wild or domestic), reptiles and birds.

OBJECTIVE

To obtain information regarding the habitat of Coccidioides spp. and the animals infected by this fungus and to identify the role that infected animals play as reservoirs and disseminators of this fungus in nature.

MATERIALS

A literature review was conducted to identify the habitat of Coccidioides spp. and the infected non-human animal species targeted by this fungus.

RESULTS AND CONCLUSIONS

This review allows us to suggest that Coccidioides spp. may be classified as halotolerant organisms; nevertheless, to perpetuate their life cycle, these organisms depend on different animal species (reservoirs) that serve as a link with the environment, by acting as disseminators of the fungi in nature.

Fungal myocarditis and pericardial effusion secondary to Inonotus tropicalis (phylum Basidiomycota) in a dog

Fungal disease is a rare cause of pericardial effusion in dogs. This report describes the first case of fungal pericardial effusion and myocarditis secondary to the fungal organism Inonotus tropicalis. A 9-year-old female spayed French bulldog with a multi-year history of treatment with glucocorticoids for management of atopy was presented for exercise intolerance, ascites and weight loss. Physical examination and thoracic imaging revealed enlarged peripheral and cranial mediastinal lymph nodes, left ventricular thickening and cardiac tamponade secondary to pericardial effusion. Fine needle aspiration of the cranial mediastinal lymph node showed pyogranulomatous inflammation with short, thin and poorly septated hyphae. Culture of the aspirate yielded a fungal isolate identified as Inonotus tropicalis based on morphologic features and rRNA gene sequencing. Postmortem examination showed myocardial thickening with multifocal to coalescing, firm, white, ill-defined nodules. Histology confirmed the presence of disseminated fungal infection with extensive myocardial involvement. Inonotus tropicalis is an opportunistic poroid wood-decaying basidiomycete. Infection in this dog was likely the result of chronic immunosuppressive therapy.

Successful Treatment of Intracardiac and Intraocular Blastomycosis in a Dog with Combination Azole Therapy

A 4 yr old spayed female Labrador retriever with clinical signs of blindness, cutaneous lesions, coughing, inappetence, and lethargy was diagnosed with disseminated blastomycosis based on cytologic (skin and lymph node aspirates) and histopathologic (skin biopsy) examinations of tissue samples. The dog deteriorated clinically during hospitalization and developed sustained ventricular tachycardia. Echocardiography revealed pericardial effusion, a nodule associated with the left ventricular papillary muscle, and a right atrial mural lesion. Therapy for myocardial performance and glaucoma was initiated. A combination of itraconazole and fluconazole successfully treated the dog. The dog regained vision in the left eye (oculus sinister [OS]) and had no residual cardiac disease detectable by either electrocardiography or echocardiography. This report is unique in documenting survival from intracardiac blastomycosis and in the use of combination azole therapy for treating disseminated disease with intraocular involvement.

Cardiac magnetic resonance in the differentiation of neoplastic and nonneoplastic pericardial effusion

BACKGROUND

Cardiac magnetic resonance (CMR) is the imaging modality of choice for cardiac tumors in people. Although neoplastic pericardial effusion (PE) carries a poor prognosis, benign idiopathic pericardial effusion does not. Definitive diagnosis is critical for surgical intervention, but currently available diagnostic techniques such as echocardiography and pericardial fluid cytology often are inconclusive.

HYPOTHESIS/OBJECTIVE

Describe CMR findings associated with PE and determine whether CMR aids in differentiation of benign and neoplastic causes of PE.

ANIMALS

Eight client-owned dogs with PE diagnosed by transthoracic echocardiography (TTE).

METHODS

CMR was performed with a 1.5 T, including dark blood, steady-state free procession cine, pre- and postcontrast T1-weighted imaging, and delayed inversion recovery prepped imaging.

RESULTS

CMR confirmed a cardiac mass and supported suspected tumor type in 4 dogs with suspected hemangiosarcoma. In 1 equivocal TTE case, CMR did not demonstrate a mass, but neoplasia was later diagnosed. In another equivocal case, CMR did not demonstrate a mass but showed findings consistent with a pericardiocentesis complication. In 1 dog without evidence of cardiac neoplasia, abdominal magnetic resonance imaging identified presumptive hepatic and splenic metastases. On reevaluation of the original CMR study, the 2 equivocal cases that were interpreted as tumor negative were reassessed as tumor positive.

CONCLUSIONS AND CLINICAL IMPORTANCE

CMR did not substantially improve diagnosis of cardiac tumors compared with TTE in these 8 cases, but it yielded useful descriptive information regarding extent, anatomic location, and potential tumor type and confirmed that CMR requires extensive additional training for tumor identification.

Coccidioidomycosis presenting as a heart base mass in two dogs

Two atypical cases of canine coccidioidomycosis presenting as heart base masses are described. An echocardiogram performed in one of the two dogs revealed a large mass at the base of the heart and a computed tomography scan showed that the mass compressed the bronchi, left atrium, aorta and pulmonary arteries. A firm, white or pale yellow mass was found at the base of the heart at necropsy examination in both cases. Microscopical examination of the masses revealed severe, chronic, locally extensive granulomatous or pyogranulomatous inflammation with intralesional spherules consistent with Coccidioides spp. The diagnosis was further confirmed by immunohistochemistry and in-situ hybridization. Coccidioides spp. have been reported to cause pericarditis in dogs, but this is the first description of coccidioidomycosis mimicking a heart-based tumour in dogs.

Coccidioidomycosis in dogs and cats: a review

The dimorphic fungi Coccidioides immitis and Coccidioides posadasii are the causative agents of coccidioidomycosis. Dogs and cats residing in and visiting endemic areas are at risk of exposure to infectious arthrospores. The primary infection is pulmonary and frequently results in chronic cough. Disseminated disease is common and causes cutaneous, osseous, cardiac, ocular, nervous system, or other organ disease. Radiographic changes include a variable degree of interstitial pulmonary infiltration, hilar lymphadenopathy, and osseous lesions. Serological titers support the diagnosis, but definitive diagnosis relies on identification of Coccidioides in cytological or tissue samples. Coccidioidomycosis should be considered in any dog or cat that has been potentially exposed during the previous 3 years and is presented with chronic illness, respiratory signs, lameness, lymphadenopathy, nonhealing cutaneous lesions, or neurological, ocular, or cardiac abnormalities.

Fungal Diagnostics: Current Techniques and Future Trends

The diagnosis of fungal disease is a challenge that requires diligent attention to history and clinical signs as well as an astute ability to interpret laboratory data. Because fungal disease can mimic other infectious and neoplastic diseases in clinical presentation, the clinician has to be aware of fungal diseases common locally as well as in other regions of the country. A global approach to the diagnosis of fungal disease that correlates clinical signs as well as physical examination, clinical pathology, and histopathology findings with serology, culture, and the newer immunohistochemical and molecular techniques, where available, is the best approach to optimize the identification of the underlying agent.

Comparative aspects of coccidioidomycosis in animals and humans

Coccidioides spp. appear capable of infecting all mammals and at least some reptiles. Development of disease as a result of infection is species-dependent. Dogs seem to have a susceptibility similar to that of humans, with subclinical infections, mild-to-severe primary pulmonary disease, and disseminated disease. Whereas central nervous system disease in humans is typically meningitis, brain disease in dogs and cats takes the form of granulomatous parenchymal masses. Osteomyelitis is the most common form of disseminated disease in the dog, while skin lesions predominate in the cat. Orally administered azole antifungal agents are the backbone of therapy in animals as they are in humans.

Coccidioidomycosis: A Diagnostic Challenge

Coccidioidomycosis is a systemic fungal infection acquired endemically in the southwestern United States. Clinical disease is quite common in the dog; though less frequently recognized in the cat, disease is often severe at the time of diagnosis. Diagnosis can be a challenge because serology, while specific, is not very sensitive and quantitative titration of antibodies does not correlate entirely with clinical disease in dogs. Radiographs, serum biochemistry tests and complete blood counts are beneficial additions to the database when establishing a diagnosis; cytology, histopathology, and culture are definitive when available. Advanced imaging can detect central nervous system and subtle skeletal lesions. Disease can occur in most organs of the body and may prove a diagnostic challenge requiring several modalities. Coccidioidomycosis may need to be considered both in animals in the endemic region and in those with a travel history through it.

Subtotal pericardectomy and epicardial excision for treatment of coccidioidomycosis-induced effusive-constrictive pericarditis in dogs: 17 cases (1999-2003)

OBJECTIVE

To determine the history, clinicopathologic findings, and results of surgery for effusive-constrictive pericarditis associated with Coccidioides immitis infection in dogs.

DESIGN

Retrospective study.

ANIMALS

17 client-owned dogs that underwent a subtotal pericardectomy and epicardial excision.

PROCEDURE

Hospital records from May 1999 to June 2003 were reviewed. Data collected included history, clinicopathologic findings, treatments, and outcome. Follow-up information was obtained via recheck examination and by use of standardized telephone interviews with referring veterinarians and owners.

RESULTS

All dogs were of large breeds, and most were male (mean age, 4.66 years). Ten dogs had no prior history of C. immitis infection, and 7 dogs had chronic infection with C. immitis. Having a chronic C. immitis infection reduced the odds of survival, compared with no previous infection. All dogs had clinical signs of right-sided heart failure. All dogs had serum titers (range, 1:8 to 1:256) for antibodies against C. immitis prior to surgery, and titers were not significantly associated with outcome. Predominant echocardiographic findings were thickened pericardium, reduced right ventricular filling, and pleural or pericardial effusion. All dogs underwent a subtotal pericardectomy and epicardial excision and had fibrosing pyogranulomatous pericarditis in biopsy specimens obtained during surgery. The perioperative mortality rate was 23.5%, and the 2-year postdischarge survival rate was 82%.

CONCLUSIONS AND CLINICAL RELEVANCE

Surgical treatment via subtotal pericardectomy and epicardial excision is successful at relieving right-sided heart failure in dogs with effusive-constrictive pericarditis secondary to C. immitis infection, but long-term treatment with antifungal agents may still be required.

Septic Pericarditis, Aortic Endarteritis, and Osteomyelitis in a Dog

A 7-year-old, female spayed rottweiler was referred with a history of an acute onset of collapse attributable to cardiac tamponade. Thoracic radiographs revealed an enlarged cardiac silhouette compatible with pericardial effusion, sternal osteomyelitis, and an unusual mineralized lesion determined later to be within the aortic wall. The pericardial effusion was a septic exudate secondary to infection with Staphylococcus species and hemorrhage into the pericardium through a mineralized aortic lesion. The case demonstrates the importance of complete evaluation of thoracic radiographs in a patient with cardiac disease and the potential value of cytopathologicalevaluation of pericardial fluid.

Update on canine and feline fungal diseases

Systemic fungal diseases cause significant morbidity and mortality in dogs and cats. Blastomycosis, histoplasmosis, coccidiomycosis, and cryptococcosis represent the four most common systemic fungal diseases. Young adult, large breed dogs generally are predisposed; cats usually do not have predictable predispositions. Intact cell-mediated immunity is essential to initial resistance to infection and response to treatment in animals. Several body systems can be affected. Diagnosis can be confirmed on the basis of clinical signs and demonstration of the causative organism. Serology is helpful with coccidiomycosis and cryptococcosis. Treatment is complicated by limited availability of fungicidal antimicrobials and the necessity of long-term treatment with expensive drugs.

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.

Septic fibrinous pericarditis in a cocker spaniel

A four-year-old cocker spaniel presented with cardiac tamponade due to a pericardial effusion, in addition to pyrexia and peripheral neutrophilia and a recent history of chest trauma. Cytological examination of the pericardial effusion revealed a predominant neutrophilia. The echocardiographic findings were of numerous hyperechoic densities in the pericardial space, due to fibrin, with concurrent thickening and distortion of the pericardium. Postmortem examination, including microbiology, revealed the presence of organising septic fibrinous pericarditis associated with a mixed infection of Streptococcus canis, Citrobacter species, Pseudomonas species and alpha-haemolytic streptococci.

Clinical, clinicopathologic, and radiographic findings in dogs with coccidioidomycosis: 24 cases (1995-2000)

OBJECTIVE

To determine clinical, clinicopathologic, and radiographic abnormalities in dogs with coccidioidomycosis.

DESIGN

Retrospective case series.

ANIMALS

24 dogs.

PROCEDURE

Clinical information and results of clinicopathologic testing were obtained from medical records. Thoracic radiographs were reviewed to characterize abnormalities.

RESULTS

Dogs ranged from 1 to 10 years old at the time of diagnosis, with 12 dogs being between 1 and 3 years old. Historical complaints included cough, lameness, signs of head or neck pain, and difficulty breathing. Mild anemia, neutrophilia, and monocytosis were common. All dogs had hypoalbuminemia, and 8 of 15 had hyperglobulinemia. Thoracic radiographs of 19 dogs were reviewed. Pulmonary infiltrates were seen in 13 dogs, with an interstitial pattern of infiltration being most common. Hilar lymphadenopathy was seen radiographically in 10 dogs. Serum from 20 dogs was tested for antibodies against Coccidioides immitis. One dog was positive for IgM antibodies, 5 were positive for IgM and IgG antibodies, and 14 were positive for IgG antibodies. Quantitative IgG titers measured in 14 dogs ranged from 1:2 to 1:128 (median and mode, 1:32). In 6 dogs, histologic examination of biopsy samples revealed fungal spherules ranging from 8 to 70 microm in diameter.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggest that in dogs, coccidioidomycosis may be associated with a wide spectrum of nonspecific respiratory and musculoskeletal abnormalities. The chronic nature of the disease makes diagnosis difficult, even in regions in which the organism is endemic.

Protection of mice against Coccidioides immitis intranasal infection by vaccination with recombinant antigen 2/PRA

Subcutaneous vaccination with recombinant antigen 2/PRA (rAg2/PRA) protected BALB/c mice against intranasal infection with Coccidioides immitis. Subcutaneously vaccinated C57BL/6 mice and intranasally vaccinated BALB/c mice were protected against larger numbers of infecting spores. Weight loss correlated with lethality, but histologic appearance did not. These studies support rAg2/PRA vaccination to prevent coccidioidomycosis.