Coccidioidal meningitis: update on epidemiology, clinical features, diagnosis, and management

Aseptic meningitis: a foundation review

PURPOSE OF REVIEW

This review addresses the multifaceted nature of aseptic meningitis, a condition with diverse infectious and noninfectious etiologies. Despite its common presentation in clinical settings, over half of the cases remain without an identified cause, necessitating a comprehensive examination of diagnostic and management strategies. The increasing availability of advanced molecular diagnostics and the challenge of distinguishing bacterial from nonbacterial cases make this an opportune time to explore its implications for clinical practice.

RECENT FINDINGS

The literature highlights the pivotal role of advanced molecular diagnostics, such as multiplex PCR and metagenomic sequencing, in improving the identification of pathogens in aseptic meningitis. Enteroviruses remain the leading cause, but pathogens like Herpesviridae, arboviruses, and nonviral agents such as fungi and spirochetes also contribute significantly. New diagnostic algorithms and clinical models are emerging to distinguish bacterial from viral meningitis, reducing unnecessary treatments.

SUMMARY

Aseptic meningitis management is evolving with advancements in diagnostic technologies that allow for earlier pathogen identification, improving patient outcomes and minimizing healthcare costs. These findings underscore the importance of timely and accurate diagnostics and tailored therapeutic strategies in both clinical and research settings. Enhanced awareness of noninfectious causes is also crucial for comprehensive care.

Spatiotemporal analysis of lung immune dynamics in lethal Coccidioides posadasii infection

Coccidioidomycosis, or Valley fever, is a lung disease caused by inhalation of Coccidioides fungi, prevalent in the Southwestern United States, Mexico, and parts of Central and South America. Annually, the United States reports 10,000-20,000 cases, although those numbers are expected to increase as climate change expands the fungal geographic range. While 60% of infections are asymptomatic, 40% symptomatic infections are often misdiagnosed due to similarities with bronchitis or pneumonia. A small subset of infection progress to severe illness, necessitating a better understanding of immune responses during lethal infection. Using single-cell RNA sequencing and spatial transcriptomics, we characterized lung responses during Coccidioides infection. We identified monocyte-derived Spp1-expressing macrophages as potential mediators of tissue remodeling and fibrosis, marked by high expression of profibrotic and proinflammatory transcripts. These macrophages showed elevated TGF-β and IL-6 signaling, pathways involved in fibrosis pathogenesis. Additionally, we observed significant neutrophil infiltration and defective lymphocyte responses, indicating severe adaptive immunity dysregulation in lethal, acute infection. These findings enhance our understanding of Coccidioides infection and suggest new therapeutic targets.IMPORTANCECoccidioidomycosis, commonly known as Valley fever, is a lung disease caused by the inhalation of Coccidioides fungi, which is prevalent in the Southwestern United States, Mexico, and parts of Central and South America. With climate change potentially expanding the geographic range of this fungus, understanding the immune responses during severe infections is crucial. Our study used advanced techniques to analyze lung responses during Coccidioides infection, identifying specific immune cells that may contribute to tissue damage and fibrosis. These findings provide new insights into the disease mechanisms and suggest potential targets for therapeutic intervention, which could improve outcomes for patients suffering from severe Valley fever.

Clinical utility of pharmacogenomic testing for patients with coccidioidal meningitis

Coccidioidomycosis can cause severe meningitis, requiring lifelong treatment. In this study, we sought to better understand the potential effect of pharmacogenomic testing on treatment outcomes of patients with coccidioidal meningitis. Of 13 patients with coccidioidal meningitis who underwent pharmacogenomic testing, 11 had genetic variants of CYP2C19 and CYP3A5 that affect antifungal efficacy. These results led to real-time treatment changes and future antifungal planning. Routine pharmacogenomic testing helps to avoid antifungal treatments that are futile or lead to adverse effects.

Atypical Parkinsonism: An Uncommon Presentation of Disseminated Coccidioidomycosis

Coccidioidomycosis is endemic in the southwestern United States, Central America, and South America. Coccidioidomycosis has a variety of clinical presentations. Coccoidal meningitis is a feared form of disseminated coccidioidomycosis with high mortality and mobility rates. We reported a case of a 64-year-old man who presented with a three-week history of gait abnormalities and back pain. The patient had atypical parkinsonism, signs of cogwheeling rigidity, a masked face, intention tremor, a shuffling gait, upgazed restriction, and long track signs of left Babinski. MRI of the brain and cervical spine demonstrated scattered foci of abnormal parenchymal and leptomeningeal enhancement. The patient later developed acute cerebral infarction before a definite diagnosis of disseminated coccidioidomycosis, which was made when the result was that serum and cerebrospinal fluid coccidioidomycosis antibodies were high. The patient started lifelong antifungal treatment. We provide a natural disease process from atypical parkinsonism to cerebral infarction to hydrocephalus to enhance awareness of the myriad clinical presentations, emphasize the importance of endemic mycoses awareness, and also put forward a question of what can be done to detect coccidioidomycosis early.

A comparison of the surgical outcomes of ventriculoperitoneal versus lumbar peritoneal shunts in the management of intracranial hypertension secondary to cryptococcal meningitis in HIV infected adult patients

OBJECTIVE

Cryptococcal meningitis (CM), an AIDS-defining illness, significantly impacts morbidity and mortality. This study aims to compare complications arising from ventriculoperitoneal shunt (VPS) and lumbar peritoneal shunt (LPS) procedures used to manage refractory intracranial hypertension (IH) secondary to CM in HIV-infected patients.

METHODS

Retrospective data were collected from January 2003 to January 2015 for HIV-infected adults diagnosed with refractory IH secondary to CM and subsequently shunted. Demographics, clinical characteristics, antiretroviral therapy, laboratory findings (including CD4 count and CSF results), CT brain scan results, shunt-related complications, and mortality were compared between VPS and LPS groups.

RESULTS

This study included 83 patients, with 60 (72%) undergoing VPS and 23 (28%) receiving LPS. Mean ages were comparable between VPS (32.5) and LPS (32.2) groups (p = 0.89). Median CD4+ counts were 76 cells/µl (IQR= 30-129) in VPS versus 54 cells/µl (IQR= 31-83) in LPS (p=0.45). VPS group showed a higher mean haemoglobin of 11.5 g/dl compared to 9.9 g/dl in the LPS group (p=0.001). CT brain scans showed hydrocephalus in 55 VPS and 13 LPS patients respectively. Shunt complications were observed in 17 (28%) VPS patients versus 10 (43.5%) LPS patients (p=0.5). Patients developing shunt sepsis in the VPS group exhibited a median CD4+ count of 117 cells/µl (IQR= 76-129) versus 48 cells/µl (IQR= 31- 66) in the LPS group (p=0.03). Early shunt malfunction occurred more frequently in the LPS group compared to VPS group (p=0.044). The mean hospital stay was 6.2 days for VPS versus 5.4 days for LPS patients (p=0.9). In-hospital mortality was 6%, occurring in three VPS and two LPS patients respectively.

CONCLUSION

Shunting procedures remain important surgical interventions for refractory IH secondary to HIV-related CM. However, cautious consideration is warranted for patients with CD4 counts below 200 cells/µL due to increased shunt complications. This study suggests a trend toward higher complication rates in patients undergoing LPS insertion.

Asymptomatic Coccidioidal Meningitis Relapse: A Demon in Disguise

Coccidioides spp is a soil-dwelling, dimorphic fungus that causes coccidioidomycosis. It is endemic to the western hemisphere. Although primarily a respiratory disease, it can also cause a myriad of clinical manifestations, from asymptomatic disease to meningitis. In fact, Coccidioides species is probably the most common etiologic agent of long-term meningitis in California and Arizona. Early diagnosis and treatment are critical to avoid fatal complications. With treatment, the cerebral spinal fluid analysis may return to normal. Relapse of coccidioidal meningitis is usually suspected with recurrence of meningitis symptoms. The patient is a 53-year-old man with a 2-decade history of coccidioidal meningitis who was diagnosed with an asymptomatic relapse of coccidioidal meningitis.

Fluconazole Failure in the Treatment of Coccidioidal Meningitis

INTRODUCTION

Coccidioidal meningitis (CM) is the most lethal form of disseminated coccidioidomycosis. Current guidelines recommend fluconazole as initial therapy but there has been a paucity of data regarding failure of fluconazole and optimal fluconazole dosage in the treatment of CM. We conducted this study to understand risk factors for fluconazole failure.

METHODS

We conducted a single-center retrospective chart review of patients diagnosed with coccidioidal meningitis between 1 January 1988 and 15 May 2021. Relevant demographic and clinical variables were collected, along with outcomes including treatment failure and death at any point. Univariate tests were conducted using the chi-squared goodness of fit test and analysis of variance.

RESULTS

Among 71 patients who began treatment for CM with fluconazole, 22 (31%) developed worsening meningitis at a median time of 206 days. Longer time from symptom onset to diagnosis of CM was a risk factor for fluconazole failure. Although the absolute failure rate of fluconazole starting dose of 400 mg daily was higher than that of 800 mg daily, the differences did not achieve statistical significance (p = 0.39).

CONCLUSION

Fluconazole failure is not uncommon in the treatment of CM. A dose of 800 mg daily was not superior to a dose of 400 mg daily. All patients on fluconazole for CM require close monitoring.

The utility of Coccidioides antigen and antibody detection in cerebrospinal fluid in the diagnosis of canine central nervous system coccidioidomycosis

OBJECTIVE

To evaluate the utility of enzyme immunoassays (EIAs) for the detection of Coccidioides antigen and antibody in CSF in the diagnosis of CNS coccidioidomycosis in dogs.

ANIMALS

51 dogs evaluated for CNS disease in a single specialty center in Tucson in 2016.

PROCEDURES

Excess CSF after routine analysis was banked after collection from dogs presented to the neurology service. Samples were tested by EIA for presence of Coccidioides antigen and antibody. Clinical data were collected from medical records retrospectively.

RESULTS

22 dogs were diagnosed with CNS coccidioidomycosis (CCM) or another neurologic disease (non-CCM). These groups of dogs overlapped in the presenting complaints, MRI results, and routine CSF analysis results. Four dogs, all with CCM, had positive antigen EIA results. With clinical diagnosis used as the reference standard, CSF antigen testing had low sensitivity (20%) but high specificity (100%) for diagnosis of CCM. Ten dogs with CCM and 4 dogs with other diagnoses had antibody detected in CSF by EIA. Sensitivity of CSF antibody testing was 46%, specificity was 86%, and positive and negative predictive values for the study population were 71% and 68%, respectively.

Clinical Relevance

Diagnosis of CNS coccidioidomycosis in dogs in an endemic region was hampered by overlap of clinical signs with other neurologic disorders and the low sensitivity of confirmatory diagnostics. The evaluated Coccidioides-specific EIAs performed on CSF can aid in the diagnosis. A prospective study is warranted to corroborate and refine these preliminary findings.

An older male with an unusual presentation of disseminated coccidioidomycosis

Coccidioidomycosis is a fungal disease endemic to the southwestern United States and other areas in the Western Hemisphere. Infection is usually acquired through inhalation. While infection is most often asymptomatic, early respiratory illness and infrequently extrapulmonary dissemination may occur. Immunocompromised individuals, particularly those with impaired cell-mediated immunity, are at greatest risk for dissemination. We present an atypical case of disseminated coccidioidomycosis in an immunocompetent male manifesting as peritoneal disease diagnosed during elective inguinal herniorrhaphy.

Pathogens in Vasculitis: Is It Really Idiopathic?

Vasculitis is an autoimmune disease characterized by the infiltration of leukocytes in blood vessels. An increasing number of studies on human and animal models have implicated various microorganisms in the pathogenesis of vasculitis. Previous studies have shown the presence of infectious agents, including viruses, bacteria, and fungi, in diseased vessels. However, despite continued research, the link between infection and vasculitis is not fully understood, possibly owing to the lack of appropriate animal models that mirror human disease and the technical limitations of pathogen detection in blood vessels. Among the pathogen-induced animal models, Candida albicans water-soluble fraction (CAWS)-induced coronary arteritis is currently considered one of the representative models of Kawasaki (KD) disease. Advances in metagenomic next-generation sequencing have enabled the detection of all nucleic acids in tissue, which can help identify candidate pathogens, including previously unidentified viruses. In this review, we discuss the findings from reports on pathogen-associated vasculitis in animal models and humans, with a specific focus on the investigation of the pathogenesis of vasculitis. Further studies on animal models and microbes in diseased vessels may provide important insights into the pathogenesis of vasculitis, which is often considered an idiopathic disease.

Methods for rapid diagnosis of meningitis etiology in adults

Infectious meningitis can be caused by viral, bacterial or fungal pathogens. Despite widely available treatments, many types of infectious meningitis are still associated with significant morbidity and mortality. Delay in diagnosis contributes to poor outcomes. Cerebrospinal fluid cultures have been used traditionally but are time intensive and sensitivity is decreased by empiric treatment prior to culture. More rapid techniques such as the cryptococcal lateral flow assay (IMMY), GeneXpert MTB/Rif Ultra (Cepheid) and FilmArray multiplex-PCR (Biofire) are three examples that have drastically changed meningitis diagnostics. This review will discuss a holistic approach to diagnosing bacterial, mycobacterial, viral and fungal meningitis.

Central Nervous System Infections Due to Coccidioidomycosis

Coccidioidomycosis is a common infection in the western and southwestern United States as well as parts of Mexico and Central and South America and is due to the soil-dwelling fungi Coccidioides. Central nervous system (CNS) infection is an uncommon manifestation that is nearly always fatal if untreated. The presentation is subtle, commonly with headache and decreased mentation. The diagnosis should be considered in patients with these symptoms in association with a positive serum coccidioidal antibody test. The diagnosis can only be established by analysis of cerebrospinal fluid (CSF), which typically demonstrates a lymphocytic pleocytosis, hypoglycorrhachia, elevated protein, and positive CSF coccidioidal antibody. Cultures are infrequently positive but a proprietary coccidioidal antigen test has reasonable sensitivity. Current therapy usually begins with fluconazole at 800 mg daily but other triazole antifungals also have efficacy and are often used if fluconazole fails. Triazole therapy should be lifelong. Intrathecal amphotericin B, the original treatment, is now reserved for those in whom triazoles have failed. There are several distinct complications of CNS coccidioidal infection, the most common of which is hydrocephalus. This is nearly always communicating and requires mechanical shunting in addition to antifungal therapy. Other complications include cerebral vasculitis, brain abscess, and arachnoiditis. Management of these is difficult and not well established.

Selected Clinical Features of Coccidioidomycosis in Dogs

Canine coccidioidomycosis, a systemic fungal infection endemic to arid and semiarid regions of North, Central, and South America, is commonly diagnosed in dogs living in or traveling through lower Sonoran life zones in the states of California and Arizona. Canine and human cases have geographic overlap. Similarities between clinical coccidioidomycosis in dogs and humans include asymptomatic infection, primary respiratory disease and disseminated disease. Differences include a high rate of dissemination in dogs, differences in predilection of dissemination sites, and a granulomatous or diffuse meningoencephalopathic form in the canine central nervous system (CNS) without the obstructive component seen in humans. Dogs presenting with CNS coccidioidomycosis most commonly experience seizures. Prior disease history and serology are unreliable indicators of CNS coccidioidomycosis. Magnetic resonance imaging (MRI) is advantageous for diagnosis of CNS coccidioidomycosis in dogs. Long-term administration of antifungal medication is promoted for treatment of both primary and disseminated coccidioidomycosis in dogs. Supportive treatment addressing pain, fever, inappetance, coughing, and other clinical signs improves patient care. Glucocorticoids and or anticonvulsants are also recommended for canine disseminated CNS disease. Protracted treatment times, lack of owner compliance, failure of the disease to respond to the first antifungal drug selected, and high cost are challenges of successfully treating dogs.

Prevalence, healthcare resource utilization and overall burden of fungal meningitis in the United States

PURPOSE

Previous epidemiological and cost studies of fungal meningitis have largely focused on single pathogens, leading to a poor understanding of the disease in general. We studied the largest and most diverse group of fungal meningitis patients to date, over the longest follow-up period, to examine the broad impact on resource utilization within the United States.

METHODOLOGY

The Truven Health Analytics MarketScan database was used to identify patients with a fungal meningitis diagnosis in the United States between 2000 and 2012. Patients with a primary diagnosis of cryptococcal, Coccidioides, Histoplasma, or Candida meningitis were included in the analysis. Data concerning healthcare resource utilization, prevalence and length of stay were collected for up to 5 years following the original diagnosis.

RESULTS

Cryptococcal meningitis was the most prevalent type of fungal meningitis (70.1 % of cases over the duration of the study), followed by coccidioidomycosis (16.4 %), histoplasmosis (6.0 %) and candidiasis (7.6 %). Cryptococcal meningitis and candidiasis patients accrued the largest average charges ($103 236 and $103 803, respectively) and spent the most time in the hospital on average (70.6 and 79 days). Coccidioidomycosis and histoplasmosis patients also accrued substantial charges and time in the hospital ($82 439, 48.1 days; $78 609, 49.8 days, respectively).

CONCLUSION

Our study characterizes the largest longitudinal cohort of fungal meningitis in the United States. Importantly, the health economic impact and long-term morbidity from these infections are quantified and reviewed. The healthcare resource utilization of fungal meningitis patients in the United States is substantial.

Coccidioidal meningitis complicated by central nervous system vasculitis in a patient with leukemia

Central Nervous System (CNS) vasculitis is the most common life-threatening complication of coccidioidal meningitis. It is manifested by cerebral ischemia, hemorrhage, and infarction. We report a case of CNS vasculitis in a patient receiving chemotherapy and review of the literature on coccidioidal meningitis. The patient was treated with combination antifungal therapy and a short course of high dose corticosteroids with a modest improvement in her neurological examination after initiation of steroids.

Efficacy of the Investigational Antifungal VT-1161 in Treating Naturally Occurring Coccidioidomycosis in Dogs

Coccidioidomycosis can be a chronic, systemic fungal infection requiring long-term to lifetime medication. Thus, there is a need for improved antifungal agents with greater efficacy and reduced toxicity. VT-1161 has a low affinity for mammalian cytochromes and potently inhibits fungal CYP51 with proven efficacy in murine models of central nervous system (CNS) and respiratory coccidioidomycosis. Dogs experience coccidioidomycosis similar to humans and are a useful preclinical model for naturally occurring disease. Twenty-four client-owned dogs diagnosed with respiratory coccidioidomycosis based on radiography, serology, clinical signs, and clinicopathologic abnormalities were treated with a loading dose of VT-1161 for 14 days, followed by 46 days of a lower maintenance dose. Twelve dogs received a high dose (29 mg/kg loading, 6 mg/kg maintenance) and 12 received a low dose (10 mg/kg loading, 1.6 mg/kg maintenance). Response to treatment was assessed by calculating the reduction in disease scores at exit compared to disease scores at enrollment. Overall, 20 of 24 (83%) dogs had ≥50% reduction in enrollment disease scores at exit (P < 0.001), with no difference between the high- and low-dose groups (P = 0.66). Time-weighted average plasma concentrations for the high- and low-dose groups were 39 ± 5 μg/ml and 19 ± 2 μg/ml, respectively. In this open-label study, VT-1161 was efficacious for the treatment of respiratory coccidioidomycosis in naturally infected dogs. Combined with previously reported murine data, this finding supports the further development of VT-1161 for the treatment of coccidioidomycosis in humans.

THE TREATMENT OF COCCIDIOIDOMYCOSIS

Therapy of coccidioidomycosis continues to evolve. For primary pulmonary disease, antifungal therapy is frequently not required while prolonged courses of antifungals are generally needed for those in whom extrathoracic disseminated has occurred. Intravenous amphotericin B should be reserved for those with severe disease. Oral triazole antifungals have had a great impact on the management of coccidioidomycosis. Both fluconazole and itraconazole at 400 mg daily have been effective for various forms of coccidioidomycosis, including meningitis, although relapse after therapy is discontinued is a problem. Individuals with suppressed cellular immunity are at increased risk for symptomatic coccidioidomycosis and they include those with HIV infection, those on immunosuppressive medications, and those who have received a solid organ transplant. Pregnant women and African-American men have been identified as two other groups who are at an increased risk for symptomatic and severe infection.

A rare cause of unintentional weight loss, anhedonia, and cognitive decline

Coccidioidal meningoencephalitis is a rare but serious neurologic disease caused by a fungus found in the southwestern United States. Because symptoms are nonspecific and complications can cause neurologic damage and death, providers should be alert for this disease in patients who have recently traveled to areas where the fungus is endemic.

Evaluation of VT-1161 for Treatment of Coccidioidomycosis in Murine Infection Models

Coccidioidomycosis, or valley fever, is a growing health concern endemic to the southwestern United States. Safer, more effective, and more easily administered drugs are needed especially for severe, chronic, or unresponsive infections. The novel fungal CYP51 inhibitor VT-1161 demonstrated in vitro antifungal activity, with MIC50 and MIC90 values of 1 and 2 μg/ml, respectively, against 52 Coccidioides clinical isolates. In the initial animal study, oral doses of 10 and 50 mg/kg VT-1161 significantly reduced fungal burdens and increased survival time in a lethal respiratory model in comparison with treatment with a placebo (P < 0.001). Oral doses of 25 and 50 mg/kg VT-1161 were similarly efficacious in the murine central nervous system (CNS) model compared to placebo treatment (P < 0.001). All comparisons with the positive-control drug, fluconazole at 50 mg/kg per day, demonstrated either statistical equivalence or superiority of VT-1161. VT-1161 treatment also prevented dissemination of infection from the original inoculation site to a greater extent than fluconazole. Many of these in vivo results can be explained by the long half-life of VT-1161 leading to sustained high plasma levels. Thus, the efficacy and pharmacokinetics of VT-1161 are attractive characteristics for long-term treatment of this serious fungal infection.

Role of Coccidioides Antigen Testing in the Cerebrospinal Fluid for the Diagnosis of Coccidioidal Meningitis

BACKGROUND

Coccidioidal meningitis (CM), a common cause of chronic meningitis in endemic area, is usually diagnosed by detection of anti-Coccidioides antibodies in cerebrospinal fluid (CSF), and findings may be negative in up to one-third of cases. CSF cultures and cytology are infrequently positive. Antigen detection has been used for the diagnosis of other forms of coccidioidomycosis and meningitis caused by other mycoses. The purpose of this study was to assess the diagnostic utility of CSF Coccidioides antigen (CAg) detection for the diagnosis of CM.

METHODS

The medical records of patients with clinically suspected meningitis, in whom CSF was tested for Coccidioides antibodies and CAg, were retrospectively reviewed, and CSF CAg testing was prospectively conducted in patients with CM. All specimens were submitted for CAg testing.

RESULTS

Thirty-six patients with 42 episode of CM were studied. The sensitivity and specificity of CAg were 93% and 100%, respectively. Cultures of CSF were positive in 7%, antibodies were demonstrated by immunodiffusion in 67% and complement fixation in 70%, and immunoglobulin M and G antibodies were demonstrated by enzyme immunoassay in 8% and 85%, respectively.

CONCLUSIONS

Testing CSF for CAg is a useful addition to diagnostic methods in suspected CM and complements testing with CSF antibodies and culture.

Recent advances in our understanding of the environmental, epidemiological, immunological, and clinical dimensions of coccidioidomycosis

Coccidioidomycosis is the endemic mycosis caused by the fungal pathogens Coccidioides immitis and C. posadasii. This review is a summary of the recent advances that have been made in the understanding of this pathogen, including its mycology, genetics, and niche in the environment. Updates on the epidemiology of the organism emphasize that it is a continuing, significant problem in areas of endemicity. For a variety of reasons, the number of reported coccidioidal infections has increased dramatically over the past decade. While continual improvements in the fields of organ transplantation and management of autoimmune disorders and patients with HIV have led to dilemmas with concurrent infection with coccidioidomycosis, they have also led to advances in the understanding of the human immune response to infection. There have been some advances in therapeutics with the increased use of newer azoles. Lastly, there is an overview of the ongoing search for a preventative vaccine.

Chronic and subacute meningitis

PURPOSE OF REVIEW

This article describes the background, clinical presentation, diagnosis, and treatment of selected etiologies of subacute and chronic meningitis. Key diagnostic considerations when evaluating a patient presenting with chronic inflammation of the CNS are discussed, and several specific infectious, neoplastic, and autoimmune etiologies are reviewed in detail.

RECENT FINDINGS

With recent advancement in serologic and CSF diagnostic testing, specific infectious, neoplastic, or autoimmune etiologies of chronic meningitis can be identified. Eliminating previous diagnostic uncertainty of chronic inflammation in the CNS has led to rapid and specific treatment regimens that ultimately improve patient outcomes. Recent advances in imaging have also aided clinicians in both their diagnostic approach and the detection of inflammatory complications such as hydrocephalus, hemorrhage, and ischemic stroke.

SUMMARY

Meningitis is defined as inflammation involving the meninges of the brain and spinal cord. Meningitis can be categorized as acute, subacute, or chronic based on duration of inflammation. This article focuses on the most common causes of subacute and chronic meningitis. Chronic meningitis is commonly defined as inflammation evolving during weeks to months without resolution of CSF abnormalities. Determining the time course of meningitis is important for creating a differential diagnosis. Most organisms causing acute meningitis rarely persist more than a few weeks. Although numerous etiologies of subacute and chronic meningitis have been identified, this article focuses on the most common etiologies: (1) infectious, (2) autoimmune, and (3) neoplastic.

Diagnostic and treatment challenges for the pediatric hematologist oncologist in endemic areas for coccidioidomycosis

Coccidioidomycosis is a mycosis endemic to certain areas in the Southwest, mostly Arizona and California, Mexico, and parts of Central and South America. Disseminated coccidioidomycosis is much more common in immunocompromised hosts; therefore, it is frequently encountered by pediatric oncologists in endemic areas. Special attention is needed to diagnose, effectively treat the infection, and appropriately adjust chemotherapy treatment plans to minimize immunosuppression. We describe the presentation and course of 6 patients with coccidioidomycosis who were seen by the pediatric hematology-oncology service at the University of Arizona during the last 3 years. Coccidioidomycosis is a relatively common infection encountered by pediatric oncologists in the southwestern states and should be considered in the differential diagnosis of patients living or visiting these areas.

Epidemiology of endemic systemic fungal infections in Latin America

Although endemic mycoses are a frequent health problem in Latin American countries, clinical and epidemiological data remain scarce and fragmentary. These mycoses have a significant impact on public health, and early diagnosis and appropriate treatment remain important. The target population for endemic disease in Latin America is mostly represented by low-income rural workers with limited access to a public or private health system. Unfortunately, diagnostic tools are not widely available in medical centers in Latin America; consequently, by the time patients are diagnosed with fungal infection, many are already severely ill. Among immunocompromised patients, endemic mycoses usually behave as opportunistic infections causing disseminated rather than localized disease. This paper reviews the epidemiology of the most clinically significant endemic mycoses in Latin America: paracoccidioidomycosis, histoplasmosis, and coccidioidomycosis. The burdens of disease, typically affected populations, and clinical outcomes also are discussed.