Diagnosis and Management of Cryptococcal Relapse

Complex Decisions in HIV-Related Cryptococcosis: Addressing Second Episodes of Cryptococcal Meningitis

PURPOSE OF REVIEW

This review highlights the difficulties in diagnosing and treating persons with a prior history of cryptococcal meningitis who improve but suffer from a recurrence of symptoms. This scenario is well known to those who frequently care for patients with cryptococcal meningitis but is not well understood. We highlight major gaps in knowledge.

RECENT FINDINGS

We recently summarized our experience with 28 persons with paradoxical immune reconstitution inflammatory syndrome (IRIS) and 81 persons with microbiological relapse. CD4 count and cerebrospinal fluid white blood cell count were higher in IRIS than relapse but neither was reliable enough to routinely differentiate these conditions. Second-episode cryptococcal meningitis remains a difficult clinical scenario as cryptococcal antigen, while excellent for initial diagnosis has no value in differentiating relapse of infection from other causes of recurrent symptoms. Updated research definitions are proposed and rapid, accurate diagnostic tests are urgently needed.

Recurrent Cryptococcal Meningitis in a Late Presenter of HIV: A Rare Case Report and Review of Literature

BACKGROUND The highly active antiretroviral treatment (HAART) and the primary prophylaxis in newly diagnosed people living with HIV (PLHIV) have reduced the incidence of opportunistic infections such as cryptococcal meningitis (CM). Relapse of CM is associated with increased morbidity and mortality. The aim of the present case presentation is to report the clinical progress relapse of CM in a man who was a late presenter PLHIV, 1 year after ART initiation with increased CD4 cell count, undetectable viral load, and excellent compliance after disruption of secondary antifungal prophylaxis. CASE REPORT One year after initial diagnosis of HIV and CM, the patient had no neurological or other symptoms, and viral suppression and increased CD4 cell count were achieved. After the completion of 12 months of secondary prophylaxis with fluconazole, an episode of partial seizure with secondary generalization occurred, followed by a short-term memory loss. Magnetic resonance imaging (MRI) indicated a focal lesion in right frontal-parietal brain region. Lumbar puncture was conducted and Cryptococcus neoformans non-resistant to fluconazole was isolated. He received antiepileptic treatment, induction antifungal treatment with liposomal amphotericin and fluconazole, consolidation treatment with fluconazole, and secondary prophylaxis with fluconazole, as in the first episode of CM. One year after the relapse, antiepileptic treatment and secondary prophylaxis with fluconazole continues and no new episode has been reported. The diagnosis of immune reconstitution inflammatory syndrome (IRIS)-related relapse of CM cannot be excluded. CONCLUSIONS Further studies are needed for the evaluation of parameters such as duration of secondary prophylaxis and treatment options for induction and consolidation therapy to reduce the relapse rate of CM.

Cryptococcal meningitis

Cryptococcus neoformans and Cryptococcus gattii species complexes cause meningoencephalitis with high fatality rates and considerable morbidity, particularly in persons with deficient T cell-mediated immunity, most commonly affecting people living with HIV. Whereas the global incidence of HIV-associated cryptococcal meningitis (HIV-CM) has decreased over the past decade, cryptococcosis still accounts for one in five AIDS-related deaths globally due to the persistent burden of advanced HIV disease. Moreover, mortality remains high (~50%) in low-resource settings. The armamentarium to decrease cryptococcosis-associated mortality is expanding: cryptococcal antigen screening in the serum and pre-emptive azole therapy for cryptococcal antigenaemia are well established, whereas enhanced pre-emptive combination treatment regimens to improve survival of persons with cryptococcal antigenaemia are in clinical trials. Short courses (≤7 days) of amphotericin-based therapy combined with flucytosine are currently the preferred options for induction therapy of cryptococcal meningitis. Whether short-course induction regimens improve long-term morbidity such as depression, reduced neurocognitive performance and physical disability among survivors is the subject of further study. Here, we discuss underlying immunology, changing epidemiology, and updates on the management of cryptococcal meningitis with emphasis on HIV-associated disease.

Clinical metagenomics-assisted diagnosis of relapsed HIV-associated cryptococcal meningitis

To date, the identification of crypotococcal relapse remains clinically challenging as it often has similar manifestation with paradoxical immune reconstitution inflammatory syndrome. This study reports on the use of metagenomics assisted next generation sequencing to aid in diagnosing recurrent cryptococcal meningitis in an person living with HIV experiencing recurring symptoms, despite negative culture results for Cryptococcus neoformans in the cerebrospinal fluid. Although fungal culture was negative, when reads from metagenomic and metatranscriptomic sequencing performed on the Day 308 cerebrospinal fluid sample were mapped onto the genome from the Day 4 isolate, 589 specific reads were identified. NCBI BLAST search also revealed Cryptococcus-specific 18S/25S/28S ribosomal RNA, indicating a relapse of the disease.

Recurrence of Symptoms Following Cryptococcal Meningitis: Characterizing a Diagnostic Conundrum With Multiple Etiologies

BACKGROUND

Cryptococcal meningitis is a common cause of AIDS-related mortality. Although symptom recurrence after initial treatment is common, the etiology is often difficult to decipher. We sought to summarize characteristics, etiologies, and outcomes among persons with second-episode symptomatic recurrence.

METHODS

We prospectively enrolled Ugandans with cryptococcal meningitis and obtained patient characteristics, antiretroviral therapy (ART) and cryptococcosis histories, clinical outcomes, and cerebrospinal fluid (CSF) analysis results. We independently adjudicated cases of second-episode meningitis to categorize patients as (1) microbiological relapse, (2) paradoxical immune reconstitution inflammatory syndrome (IRIS), (3) persistent elevated intracranial pressure (ICP) only, or (4) persistent symptoms only, along with controls of primary cryptococcal meningitis. We compared groups with chi-square or Kruskal-Wallis tests as appropriate.

RESULTS

724 participants were included (n = 607 primary episode, 81 relapse, 28 paradoxical IRIS, 2 persistently elevated ICP, 6 persistent symptoms). Participants with culture-positive relapse had lower CD4 (25 cells/μL; IQR: 9-76) and lower CSF white blood cell (WBC; 4 cells/μL; IQR: 4-85) counts than paradoxical IRIS (CD4: 78 cells/μL; IQR: 47-142; WBC: 45 cells/μL; IQR: 8-128). Among those with CSF WBC <5 cells/μL, 86% (43/50) had relapse. Among those with CD4 counts <50 cells/μL, 91% (39/43) had relapse. Eighteen-week mortality (from current symptom onset) was 47% among first episodes of cryptococcal meningitis, 31% in culture-positive relapses, and 14% in paradoxical IRIS.

CONCLUSIONS

Poor immune reconstitution was noted more often in relapse than IRIS as evidenced by lower CSF WBC and blood CD4 counts. These easily obtained laboratory values should prompt initiation of antifungal treatment while awaiting culture results.

CLINICAL TRIALS REGISTRATION

NCT01802385.

Cerebral Cryptococcomas: A Systematic Scoping Review of Available Evidence to Facilitate Diagnosis and Treatment

Background: Recommendations for managing patients with cerebral cryptococcomas are scarce across multiple clinical guidelines. Due to the deficiency of high-quality data coupled with an increasing number of at-risk patients, the purpose of this review is to describe the demographic characteristics, causative pathogen, intracranial imaging, surgical and/or pharmacological interventions, as well as outcomes of patients with cerebral cryptococcomas to improve recognition and management. Methods: We conducted a scoping review in accordance with the PRISMA guidelines using PubMed and Web of Science. Reports were included if the following details were presented: (1) site of infection; (2) treatment details which at least include the specific antifungal therapy administered, if applicable; and (3) patient outcome. Results: A total of 40 records representing 47 individual patients were included, of which the median age was 48.5 years, 75% were male, and 60% reported a significant past medical, surgical, or social history. C. neoformans was isolated more often than C. gattii (74% vs. 26%, respectively). Patients most often presented with headache, altered mental status and/or confusion, and vomiting occurring over a median of 30 days; though few were noted to have significant findings on physical examination. More than 50% of patients had a single cerebral cryptococcoma lesion, whereas perilesional edema was present in 73% of cases. Surgical intervention occurred in 49% of patients. An amphotericin B-based formulation was administered as “induction” therapy to 91% of patients, but combined with flucytosine or fluconazole in only 58%, for an overall median of 42 days. Fifty two percent of patients received “maintenance” therapy for a median of 126 days, in which fluconazole was most often used. Corticosteroids were administered to approximately 30% of patients for a median of 31.5 days. Overall, mortality was 34%. Conclusion: Based on our findings, management should include antifungal therapy for a minimum of 6 months with considerations for concomitant corticosteroids in the setting of perilesional edema, as well as surgical intervention. Emphasis should be placed on providing well-documented treatment details in future case reports and series to allow for the development of more concise evidence-based recommendations.

Disseminated Cryptococcal Infection in HIV-Infected Patients: A Retrospective Clinicopathological Review of 4 Autopsy Cases

Cryptococcosis is an opportunistic infection with high mortality if not diagnosed and treated in time. The objective of this study was to review the clinicopathological information of decendents with final autopsy diagnosis of disseminated cryptococcal infection. This study collected data from 4 decendents who presented to an academic hospital/laboratory between 1 January 2015 to 31 December 2018. Their clinical, radiological and pathological findings including treatment were reviewed. Two decendents presented with respiratory symptoms whilst the other 2 presented with meningeal symptoms. Three were confirmed HIV positive. One decendent was on ART, one had defaulted treatment and one was ART naïve. Two decendents were diagnosed with cryptococcal meningitis, one with bacterial pneumonia and one with pulmonary tuberculosis. Three decendents died in emergency unit and one in the ward whilst on antifungal therapy. The autopsy findings confirmed disseminated cryptococcal infection in all cases. A high index of suspicion should be maintained in the right clinical context. Multi-organ involvement should be suspected in all patients and be actively sought out.

Cryptococcal meningitis: a review for emergency clinicians

INTRODUCTION

Cryptococcal Meningitis (CM) remains a high-risk clinical condition, and many patients require emergency department (ED) management for complications and stabilization.

OBJECTIVE

This narrative review provides an evidence-based summary of the current data for the emergency medicine evaluation and management of CM.

DISCUSSION

This review evaluates the diagnosis, management, and empiric treatment of suspected CM in the ED. CM can easily evade diagnosis with a subacute presentation, and should be considered in any patient with a headache, neurological deficit, or who is immunocompromised. As a definitive diagnosis of CM will not be made in the ED, management of a patient with suspected CM includes prompt diagnostic testing and initiation of empiric treatment. Multiple types of newer Cryptococcal antigen tests provide high sensitivity and specificity both in serum and cerebrospinal fluid (CSF). Patients should be treated empirically for bacterial, fungal, and viral meningitis, specifically with amphotericin B and flucytosine for presumed CM. Additionally, appropriate resuscitation and supportive care, including advanced airway management, management of increased intracranial pressure (ICP), antipyretics, intravenous fluids, and isolation, should be initiated. Antiretroviral therapy (ART) should not be initiated in the ED for those found or known to be HIV-positive for risk of immune reconstitution inflammatory syndrome (IRIS).

CONCLUSIONS

CM remains a rare clinical presentation, but carries significant morbidity and mortality. Physicians must rapidly diagnose these patients while evaluating for other diseases and complications. Early consultation with an infectious disease specialist is imperative, as is initiating symptomatic care.

Potential Predictors and Survival Analysis of the Relapse of HIV-Associated Cryptococcal Meningitis: A Retrospective Study

Objective: We intend to investigate the relapse of HIV-associated cryptococcal meningitis (CM), assess potential predictors and conduct survival analysis, with a view to establishing a valid reference for the management of the relapse of CM.

Method: This is a retrospective study in Chinese patients with HIV-associated CM and those who experience relapse of CM. Baseline demographic, laboratory and clinical characteristics of patients with HIV-associated CM were collected. Predictors for relapse of HIV-associated CM were analyzed using univariate and multivariate logistic regression. Survival probability in relapse cases was determined by Kaplan-Meier survival curves.

Results: During the study period, 87 of 348 (25.0%) HIV patients experienced the relapse of CM. CD4+ T-cell counts, antiretroviral therapy (ART) status and the time from symptom onset to presentation were all statistically associated with the relapse of CM (p = 0.013, 0.018 and 0.042, respectively). The overall survival among 46 HIV CM relapse patients whose survival information were obtained, was 78.3%. The proportion of patients who died after antifungal treatment for CM was greater in those whose interval from symptom onset to presentation ≥4 weeks, compared with those <4 weeks (p = 0.0331).

Conclusions: In order to reduce the relapse of CM and increase the survival possibility of these patients, we can promote the importance of ART before CM occurs, emphasize timely consultation when any CM-associated clinical symptoms occurs, and individualized the timing of ART initiation according to indicators which can reflect the severity of CM.

HIV-Associated Cryptococcal Meningitis Patients Treated with Amphotericin B Deoxycholate Plus Flucytosine under Routine Care Conditions in a Referral Center in São Paulo, Brazil

BACKGROUND

Cryptococcal meningitis remains a common cause of mortality in low- and middle-income countries, where amphotericin B deoxycholate (amphotericin) plus fluconazole is the most common treatment. Flucytosine is almost uniformly absent as is outcome data on flucytosine use in routine care. The main goal of this study was identified the cumulative mortality at 2, 4, and 10 weeks after hospital admission.

METHODS

We conducted a retrospective, observational cohort study among HIV-infected adults with cryptococcal meningitis receiving amphotericin plus flucytosine as induction therapy in Brazil. We assessed cumulative mortality at 2, 4, and 10 weeks and the cumulative proportion discontinuating amphotericin or flucytosine due to toxicity at 2 weeks. We performed multiple logistic regression to identify variables associated with in-hospital mortality.

RESULTS

In total, 77 individuals (n = 66 men) were included with median baseline CD4 of 29 (IQR, 9-68) cells/mcL. Twenty (26%) had at least one concurrent neurological disease diagnosed. Sixty (78%) patients received at least 14 days of amphotericin plus flucytosine. Cumulative mortality was 5% (4/77) at 2 weeks, 8% (6/77) at 4 weeks, and 19% (15/77) at 10 weeks. Cumulative proportion of patients that discontinuated amphotericin or flucytosine due to toxicity was 20% (16/77) at 2 weeks. In addition, in-hospital mortality was associated with receiving ≤ 10 days of induction therapy (odds ratio = 4.5, 95% CI 1.2-17.1, P = 0.028) or positive cerebrospinal fluid fungal culture after 2 weeks (odds ratio = 3.8, 95% CI 1.1-13.5, P = 0.035).

CONCLUSION

In this "real-world" study, amphotericin plus flucytosine shows low early mortality of patients with HIV-associated cryptococcal meningitis. Early discontinuation due to adverse events was moderate. More effective and safe antifungals are needed in order to improve the outcome of cryptococcal meningitis.

Effective Voriconazole in an Immunocompetent Patient With Amphotericin B Resistant Systemic Cryptococcal Granulomatosis

The diagnostic management of systemic granulomatosis is a difficult clinical exercise. The most frequent etiologies are tuberculosis and sarcoidosis. However, it is important to search as well for the other causes of granulomas, especially infections and malignancies, the prognosis of which can be poor without adequate treatment. A 67-year-old immunocompetent patient presented with granulomatous adenitis without caseous necrosis. The etiological evaluation had revealed neurological, pulmonary and lymph node systemic cryptococcosis. Conventional antifungal therapy with the triple combination Amphotericin B - Flucytosine - Fluconazole has not been effective, indicating administration of voriconazole. The evolution was rapidly favorable with apyrexia after 48 hours, disappearance of clinical symptoms, normalization of biological parameters of cerebrospinal fluid (CSF) and major improvement of radiological abnormalities. This clinical case is original by the disseminated involvement, the patient's non-immunocompromised status and the primary resistance to amphotericin B. Our findings underline the importance of carrying out an exhaustive evaluation, reflecting on cryptococcosis in any systemic granulomatosis and knowing the various therapeutic alternatives, in particular, voriconazole if primary response to amphotericin B has not been obtained.

Molecular Epidemiology Reveals Low Genetic Diversity among Cryptococcus neoformans Isolates from People Living with HIV in Lima, Peru, during the Pre-HAART Era

Cryptococcosis, a mycosis presenting mostly as meningoencephalitis, affecting predominantly human immunodeficiency virus (HIV)-infected people, is mainly caused by Cryptococcus neoformans. The genetic variation of 48 C. neoformans isolates, recovered from 20 HIV-positive people in Lima, Peru, during the pre-highly active antiretroviral therapy (HAART) era, was studied retrospectively. The mating type of the isolates was determined by PCR, and the serotype by agglutination and CAP59-restriction fragment length polymorphism (RFLP). Genetic diversity was assessed by URA5-RFLP, PCR-fingerprinting, amplified fragment length polymorphism (AFLP), and multilocus sequence typing (MLST). All isolates were mating type alpha, with 39 molecular type VNI, seven VNII, corresponding to C. neoformans var. grubii serotype A, and two VNIII AD hybrids. Overall, the cryptococcal population from HIV-positive people in Lima shows a low degree of genetic diversity. In most patients with persistent cryptococcal infection, the same genotype was recovered during the follow-up. In four patients with relapse and one with therapy failure, different genotypes were found in isolates from the re-infection and from the isolate recovered at the end of the treatment. In one patient, two genotypes were found in the first cryptococcosis episode. This study contributes data from Peru to the ongoing worldwide population genetic analysis of Cryptococcus.

Cryptococcal infections in children: retrospective study and review from Australia

Aim: Cryptococcosis causes significant morbidity and mortality worldwide, but pediatric data are limited. Methods: A retrospective literature review of Australian pediatric cryptococcosis and additional 10-year audit of cases from a large pediatric network. Results: 22 cases of cryptococcosis in children were identified via literature review: median age was 13.5 years (IQR 7.8-16 years), 18/22 (82%) had meningitis or central nervous system infection. Where outcome was reported, 11/18 (61%) died. Of six audit cases identified from 2008 to 2017, 5 (83%) had C. gattii disease and survived. One child with acute lymphoblastic leukemia and C. neoformans infection died. For survivors, persisting respiratory or neurological sequelae were reported in 4/6 cases (67%). Conclusion: Cryptococcosis is uncommon in Australian children, but is associated with substantial morbidity.

TNF-α-Producing Cryptococcus neoformans Exerts Protective Effects on Host Defenses in Murine Pulmonary Cryptococcosis

Tumor necrosis factor alpha (TNF-α) plays a critical role in the control of cryptococcal infection, and its insufficiency promotes cryptococcal persistence. To explore the therapeutic potential of TNF-α supplementation as a booster of host anti-cryptococcal responses, we engineered a C. neoformans strain expressing murine TNF-α. Using a murine model of pulmonary cryptococcosis, we demonstrated that TNF-α-producing C. neoformans strain enhances protective elements of host response including preferential T-cell accumulation and improved Th1/Th2 cytokine balance, diminished pulmonary eosinophilia and alternative activation of lung macrophages at the adaptive phase of infection compared to wild type strain-infected mice. Furthermore, TNF-α expression by C. neoformans enhanced the fungicidal activity of macrophages in vitro. Finally, mice infected with the TNF-α-producing C. neoformans strain showed improved fungal control and considerably prolonged survival compared to wild type strain-infected mice, but could not induce sterilizing immunity. Taken together, our results support that TNF-α expression by an engineered C. neoformans strain while insufficient to drive complete immune protection, strongly enhanced protective responses during primary cryptococcal infection.

Diagnosis and Management of Central Nervous System Cryptococcal Infections in HIV-Infected Adults

Cryptococcal meningitis persists as a significant source of morbidity and mortality in persons with HIV/AIDS, particularly in sub-Saharan Africa. Despite increasing access to antiretrovirals, persons presenting with advanced HIV disease remains common, and Cryptococcus remains the most frequent etiology of adult meningitis. We performed a literature review and herein present the most up-to-date information on the diagnosis and management of cryptococcosis. Recent advances have dramatically improved the accessibility of timely and affordable diagnostics. The optimal initial antifungal management has been newly updated after the completion of a landmark clinical trial. Beyond antifungals, the control of intracranial pressure and mitigation of toxicities remain hallmarks of effective treatment. Cryptococcal meningitis continues to present challenging complications and continued research is needed.

[Cryptococcal meningoencephalitis in an immunocompetent patient caused by late onset exacerbation]

The case was a 29-year-old male with no previous history of serious disease. He developed headache and fever, which then worsened and he was admitted to our hospital. His temperature was 38.3°C and he had a stiff neck. In cerebrospinal fluid (CSF) tests, the opening pressure was high, the cell count was increased, and the CSF/serum glucose ratio was decreased. In addition, he was positive for cryptococcal antigen. According to these findings, he was diagnosed with cryptococcal meningoencephalitis and antifungal treatment was initiated. His symptoms then improved, but on day 18 after admission, he developed convulsions, and on day 28, right visual field defects appeared. Brain MRI showed disseminated lesions in the bilateral cerebral cortex. Despite a decrease of the cryptococcal antigenic value in the CSF, the IgG index was elevated. IL-6, 8 and 10 in CSF were high levels on Day 1, then gradually reduced as the symptoms improved. But on Day 28, worsening of symptoms, IL-10 was significantly increased dispite IL-6 and 8 reducing. Therefore, the exacerbation of his symptoms and expansion of the lesions were not caused by the Cryptococcus itself, and it was considered that they were due to the late deterioration of cryptococcosis, which responded to steroid treatment.

CD4+ T Cells Orchestrate Lethal Immune Pathology despite Fungal Clearance during Cryptococcus neoformans Meningoencephalitis

Cryptococcus neoformans is a major fungal pathogen that disseminates to the central nervous system (CNS) to cause fatal meningoencephalitis, but little is known about immune responses within this immune-privileged site. CD4⁺ T cells have demonstrated roles in anticryptococcal defenses, but increasing evidence suggests that they may contribute to clinical deterioration and pathology in both HIV-positive (HIV+) and non-HIV patients who develop immune reconstitution inflammatory syndrome (IRIS) and post-infectious inflammatory response syndrome (PIIRS), respectively. Here we report a novel murine model of cryptococcal meningoencephalitis and a potential damaging role of T cells in disseminated cryptococcal CNS infection. In this model, fungal burdens plateaued in the infected brain by day 7 postinfection, but activation of microglia and accumulation of CD45^hi leukocytes was significantly delayed relative to fungal growth and did not peak until day 21. The inflammatory leukocyte infiltrate consisted predominantly of gamma interferon (IFN-γ)-producing CD4⁺ T cells, conventionally believed to promote fungal clearance and recovery. However, more than 50% of mice succumbed to infection and neurological dysfunction between days 21 and 35 despite a 100-fold reduction in fungal burdens. Depletion of CD4⁺ cells significantly impaired IFN-γ production, CD8⁺ T cell and myeloid cell accumulation, and fungal clearance from the CNS but prevented the development of clinical symptoms and mortality. These findings conclusively demonstrate that although CD4⁺ T cells are necessary to control fungal growth, they can also promote significant immunopathology and mortality during CNS infection. The results from this model may provide important guidance for development and use of anti-inflammatory therapies to minimize CNS injury in patients with severe cryptococcal infections.

CNS infection with the fungal pathogen Cryptococcus neoformans often results in debilitating brain injury and has a high mortality rate despite antifungal treatment. Treatment is complicated by the fact that immune responses needed to eliminate infection are also thought to drive CNS damage in a subset of both HIV+ and non-HIV patients. Thus, physicians need to balance efforts to enhance patients’ immune responses and promote microbiological control with anti-inflammatory therapy to protect the CNS. Here we report a novel model of cryptococcal meningoencephalitis demonstrating that fungal growth within the CNS does not immediately cause symptomatic disease. Rather, accumulation of antifungal immune cells critically mediates CNS injury and mortality. This model demonstrates that antifungal immune responses in the CNS can cause detrimental pathology and addresses the urgent need for animal models to investigate the specific cellular and molecular mechanisms underlying cryptococcal disease in order to better treat patients with CNS infections.

Neurosyphilis with Concomitant Cryptococcal and Tuberculous Meningitis in a Patient with AIDS: Report of a Unique Case

Meningitis in individuals living with acquired immunodeficiency syndrome (AIDS) is most frequently infectious in origin and usually due to opportunistic infections. The most common pathogens are Cryptococcus neoformans and Mycobacterium tuberculosis. Treponema pallidum causes neurosyphilis and can complicate HIV infections at any time after the initial infection. Simultaneous infections of the central nervous system caused by these pathogens are very uncommon even in the setting of severe immunosuppression. We report the case of a newly diagnosed HIV/AIDS young man who was found to have neurosyphilis with Cryptococcus meningitis. After a few weeks of treatment and initiation of antiretroviral therapy, he was also diagnosed with tuberculous meningitis, which was probably unmasked by the development of immune reconstitution inflammatory syndrome (IRIS). To the best of our knowledge, this is the only case of reported neurosyphilis and meningitis caused concomitantly by Cryptococcus and Mycobacterium tuberculosis.

T Cell-Restricted Notch Signaling Contributes to Pulmonary Th1 and Th2 Immunity during Cryptococcus neoformans Infection

Cryptococcus neoformans is a ubiquitous, opportunistic fungal pathogen but the cell signaling pathways that drive T cell responses regulating antifungal immunity are incompletely understood. Notch is a key signaling pathway regulating T cell development, and differentiation and functional responses of mature T cells in the periphery. The targeting of Notch signaling within T cells has been proposed as a potential treatment for alloimmune and autoimmune disorders, but it is unknown whether disturbances to T cell immunity may render these patients vulnerable to fungal infections. To elucidate the role of Notch signaling during fungal infections, we infected mice expressing the pan-Notch inhibitor dominant negative mastermind-like within mature T cells with C. neoformans Inhibition of T cell-restricted Notch signaling increased fungal burdens in the lungs and CNS, diminished pulmonary leukocyte recruitment, and simultaneously impaired Th1 and Th2 responses. Pulmonary leukocyte cultures from T cell Notch-deprived mice produced less IFN-γ, IL-5, and IL-13 than wild-type cells. This correlated with lower frequencies of IFN-γ-, IL-5-, and IL-13-producing CD4⁺ T cells, reduced expression of Th1 and Th2 associated transcription factors, Tbet and GATA3, and reduced production of IFN-γ by CD8⁺ T cells. In contrast, Th17 responses were largely unaffected by Notch signaling. The changes in T cell responses corresponded with impaired macrophage activation and reduced leukocyte accumulation, leading to diminished fungal control. These results identify Notch signaling as a previously unappreciated regulator of Th1 and Th2 immunity and an important element of antifungal defenses against cryptococcal infection and CNS dissemination.

Progressive cutaneous Cryptococcosis complicated with meningitis in a myasthenia gravis patient on long-term immunosuppressive therapy - a case report

BACKGROUND

Cryptococcosis is an opportunistic infection caused by the encapsulated yeast Cryptococcus neoformans and most remarkably manifests in HIV-infected individuals, especially in the settings of very low CD4 count. Development of cryptococcosis in HIV-uninfected individuals is exceedingly rare and usually signifies a marked immunodeficiency. Cryptococcosis in association with myasthenia gravis or thymoma has been previously documented in only very few cases in the literature.

CASE PRESENTATION

We reported a complicated case of severe cutaneous cryptococcosis in a 39-year-old Vietnamese male patient with myasthenia gravis on long-term immunosuppressive therapy. The patient presented with a five month history of recurrent and progressive skin lesions that later on progressed into cryptococcal meningitis.

CONCLUSION

Through this case, we aimed to emphasize the importance of including cutaneous cryptococcosis in the differential diagnosis of cutaneous lesions in patients on chronic immunosuppressive therapy. The cutaneous manifestations of cryptococcosis can be the first clue for a disseminated disease, which makes early recognition crucial and life-saving.

Recent advances in AIDS-related cryptococcal meningitis treatment with an emphasis on resource limited settings

INTRODUCTION

Recent advances in the treatment and prevention of cryptococcal meningitis have the potential to decrease AIDS-related deaths. Areas covered: Targeted screening for asymptomatic cryptococcal antigenemia in persons with AIDS is a cost effective method for reducing early mortality in patients on antiretroviral therapy. For persons with symptomatic cryptococcal meningitis, optimal initial management with amphotericin and flucytosine improves survival compared to alternative therapies; however, amphotsericin is difficult to administer and flucytosine has not been available in middle or low income countries, where cryptococcal meningitis is most prevalent. Expert commentary: Improved care for cryptococcal meningitis patients in resource-limited settings is possible, and new treatment possibilities are emerging.

Diagnostic performance of a multiplex PCR assay for meningitis in an HIV-infected population in Uganda

Meningitis remains a worldwide problem, and rapid diagnosis is essential to optimize survival. We evaluated the utility of a multiplex PCR test in differentiating possible etiologies of meningitis. Cerebrospinal fluid (CSF) from 69 HIV-infected Ugandan adults with meningitis was collected at diagnosis (n=51) and among persons with cryptococcal meningitis during therapeutic lumbar punctures (n=68). Cryopreserved CSF specimens were analyzed with BioFire FilmArray® Meningitis/Encephalitis panel, which targets 17 pathogens. The panel detected Cryptococcus in the CSF of patients diagnosed with a first episode of cryptococcal meningitis by fungal culture with 100% sensitivity and specificity and differentiated between fungal relapse and paradoxical immune reconstitution inflammatory syndrome in recurrent episodes. A negative FilmArray result was predictive of CSF sterility on follow-up lumbar punctures for cryptococcal meningitis. EBV was frequently detected in this immunosuppressed population (n=45). Other pathogens detected included: cytomegalovirus (n=2), varicella zoster virus (n=2), human herpes virus 6 (n=1), and Streptococcus pneumoniae (n=1). The FilmArray Meningitis/Encephalitis panel offers a promising platform for rapid meningitis diagnosis.

Development of cryptococcal immune reconstitution inflammatory syndrome 41 months after the initiation of antiretroviral therapy in an AIDS patient

Cryptococcal meningitis is one of the most lethal fungal infections in patients with acquired immune deficiency syndrome (AIDS). The incidence of and mortality from cryptococcal meningitis have markedly decreased since the introduction of combination antiretroviral therapy (cART). However, despite its benefits, the initiation of cART results in immune reconstitution inflammatory syndrome (IRIS) in some patients. Although IRIS is occasionally difficult to distinguish from relapse or treatment failure, the distinction is important because IRIS requires a different treatment. Here, we present the case of a patient with AIDS who developed symptoms of cryptococcal IRIS 41 months after starting cART. To the best of our knowledge, the time between cART initiation and the onset of cryptococcal IRIS in this patient is the longest that has been reported in the literature.

LATERAL FLOW ASSAY FOR CRYPTOCOCCAL ANTIGEN: AN IMPORTANT ADVANCE TO IMPROVE THE CONTINUUM OF HIV CARE AND REDUCE CRYPTOCOCCAL MENINGITIS-RELATED MORTALITY

AIDS-related cryptococcal meningitis continues to cause a substantial burden of death in low and middle income countries. The diagnostic use for detection of cryptococcal capsular polysaccharide antigen (CrAg) in serum and cerebrospinal fluid by latex agglutination test (CrAg-latex) or enzyme-linked immunoassay (EIA) has been available for over decades. Better diagnostics in asymptomatic and symptomatic phases of cryptococcosis are key components to reduce mortality. Recently, the cryptococcal antigen lateral flow assay (CrAg LFA) was included in the armamentarium for diagnosis. Unlike the other tests, the CrAg LFA is a dipstick immunochromatographic assay, in a format similar to the home pregnancy test, and requires little or no lab infrastructure. This test meets all of the World Health Organization ASSURED criteria (Affordable, Sensitive, Specific, User friendly, Rapid/robust, Equipment-free, and Delivered). CrAg LFA in serum, plasma, whole blood, or cerebrospinal fluid is useful for the diagnosis of disease caused by Cryptococcus species. The CrAg LFA has better analytical sensitivity for C. gattii than CrAg-latex or EIA. Prevention of cryptococcal disease is new application of CrAg LFA via screening of blood for subclinical infection in asymptomatic HIV-infected persons with CD4 counts < 100 cells/mL who are not receiving effective antiretroviral therapy. CrAg screening of leftover plasma specimens after CD4 testing can identify persons with asymptomatic infection who urgently require pre-emptive fluconazole, who will otherwise progress to symptomatic infection and/or die.

Methods of rapid diagnosis for the etiology of meningitis in adults

Infectious meningitis may be due to bacterial, mycobacterial, fungal or viral agents. Diagnosis of meningitis must take into account numerous items of patient history and symptomatology along with regional epidemiology and basic cerebrospinal fluid testing (protein, etc.) to allow the clinician to stratify the likelihood of etiology possibilities and rationally select additional diagnostic tests. Culture is the mainstay for diagnosis in many cases, but technology is evolving to provide more rapid, reliable diagnosis. The cryptococcal antigen lateral flow assay (Immuno-Mycologics) has revolutionized diagnosis of cryptococcosis and automated nucleic acid amplification assays hold promise for improving diagnosis of bacterial and mycobacterial meningitis. This review will focus on a holistic approach to diagnosis of meningitis as well as recent technological advances.

Cryptococcal Meningitis: Diagnosis and Management Update

Recent advances in the diagnosis and management of cryptococcal meningitis are promising and have been improving long-term survival. Point of care testing has made diagnosing cryptococcal meningitis rapid, practical, and affordable. Targeted screening and treatment programs for cryptococcal antigenemia are a cost effective method for reducing early mortality on antiretroviral therapy (ART). Optimal initial management with amphotericin and flucytosine improves survival against alternative therapies, although amphotericin is difficult to administer and flucytosine is not available in middle or low income countries, where cryptococcal meningitis is most prevalent. Controlling increased intracranial pressure with serial therapeutic lumbar punctures has a proven survival benefit. Delaying ART initiation for 4 weeks after the diagnosis of cryptococcal meningitis is associated with improved survival. Fortunately, new approaches have been leading the way toward improving care for cryptococcal meningitis patients. New trials utilizing different combinations of antifungal therapy are reviewed, and we summarize the efficacy of different regimens.

Cryptococcal meningoencephalitis relapse after an eight-year delay: an interplay of infection and immune reconstitution

We report a case of a symptomatic relapse of HIV-related cryptococcal meningoencephalitis eight years after the first diagnosis on the background of immune reconstitution. The findings as well as the clinical course suggests a combination of smouldering localised infection and enhanced inflammatory reaction related to immune restoration due to antiretroviral therapy. A combination of antifungal and anti-inflammatory therapy resulted in clinical and radiological improvement. Our case challenges the concept that immune reconstitution inflammatory syndrome and microbiological relapse are dichotomous entities.

Detection of High Cerebrospinal Fluid Levels of (1→3)-β-d-Glucan in Cryptococcal Meningitis

(1→3)-Beta-D-glucan was detected in high levels in cerebrospinal fluid, and to lesser extent in serum, among HIV-infected persons with cryptococcal meningitis.

Background

 (1→3)-β-d-Glucan (BDG) is a helpful diagnostic marker for many invasive fungal infections. However, BDG is not thought to be useful in diagnosing cryptococcosis. We evaluated the utility of BDG as an adjunct diagnostic tool for patients infected with human immunodeficiency virus (HIV) and presenting with suspected cryptococcal meningitis.

Methods

 The Fungitell assay was used to measure BDG concentrations in cerebrospinal fluid (CSF) (n = 177) and serum (n = 109) of HIV-infected Ugandans and South Africans with suspected meningitis. Correlations between BDG concentrations and quantitative CSF cryptococcal cultures, CSF cryptococcal antigen (CRAG) titers, and 18 different CSF cytokine concentrations were assessed using non-parametric tests. Mixed models evaluated longitudinal changes in CSF BDG concentrations. Survival analyses were used to evaluate BDG's relationship with mortality.

Results

 The Fungitell BDG assay provided 89% sensitivity and 85% specificity in CSF for cryptococcal meningitis. Serum sensitivity was suboptimal (79%). Cerebrospinal fluid BDG concentrations at diagnosis were median (interquartile range) 343 (200–597) pg/mL in cryptococcal patients and 37 (23–46) pg/mL in patients without cryptococcosis. Sensitivity in CSF improved to 98% (53 of 54) when initial fungal burdens were ≥10 000 colony-forming units/mL. (1→3)-β-d-Glucan normalized rapidly after initiating antifungal therapy. Baseline BDG concentrations correlated with CSF fungal burden (rho = 0.820; P < .001), CSF CRAG lateral flow assay titers (rho = 0.780, P < .001), and monocyte chemotactic protein-1 levels in CSF (P = .047). In patients with cryptococcal meningitis, BDG ≥500 pg/mL at diagnosis was associated with increased 10-week mortality.

Conclusions

 (1→3)-β-d-Glucan is detectable in the CSF of HIV-infected patients with Cryptococcus, and it may provide useful prognostic information. Sensitivity is less than CRAG; however, BDG normalizes rapidly, unlike CRAG, making BDG potentially useful in diagnosing recurrent episodes.

Extensive Central Nervous System Cryptococcal Disease Presenting as Immune Reconstitution Syndrome in a Patient with Advanced HIV: Report of a Case and Review of Management Dilemmas and Strategies

One of the complications of the use of antiretroviral therapy (ART), immune reconstitution inflammatory syndrome (IRIS), is particularly problematic in the management of cryptococcal meningitis. We present the case of a 35-year-old male with acquired immune deficiency syndrome diagnosed with extensive central nervous system (CNS) cryptococcal disease, including meningitis and multiple intracranial cysts, diagnosed eight weeks after the initiation of ART. The patient experienced a relapsing and remitting clinical course despite repeated courses of potent antifungal therapy and aggressive management of raised intracranial pressure. This review highlights therapeutic dilemmas and strategies in the management of CNS cryptococcosis complicated with IRIS and highlights gaps in available treatment guidelines.

Central nervous system cryptococcoma in a Ugandan patient with Human Immunodeficiency Virus

Mortality due to AIDS-related Cryptococcal meningitis (CM) is often >50% in low-middle income countries. Dissemination of CM can result in intracranial mass lesions known as cryptococcoma. Patients who develop cryptococcomas often have worse outcomes when compared to patients with cryptococcosis without cryptococcoma. We describe a cryptococcoma in the central nervous system (CNS) in a Ugandan patient with AIDS, and review the diagnosis and management with special focus on difficulties encountered in low or middle-income countries.