The use of ventriculoperitoneal shunts for uncontrollable intracranial hypertension in patients with HIV-associated cryptococcal meningitis with or without hydrocephalus

Nomogram to Predict the Outcome of Ventriculoperitoneal Shunt Among Patients with Non-HIV Cryptococcal Meningitis

BACKGROUND

The ventriculoperitoneal (VP) shunt is widely acknowledged as a treatment option for managing intracranial hypertension resulting from non-human immunodeficiency virus (HIV) cryptococcal meningitis (CM). Nonetheless, there is currently no consensus on the appropriate surgical indications for this procedure. Therefore, it is crucial to conduct a preoperative evaluation of patient characteristics and predict the outcome of the VP shunt to guide clinical treatment effectively.

METHODS

A retrospective analysis was conducted on data from 85 patients with non-HIV CM who underwent VP shunt surgery at our hospital. The analysis involved studying demographic data, preoperative clinical manifestations, cerebrospinal fluid (CSF) characteristics, and surgical outcomes and comparisons between before and after surgery. A nomogram was developed and evaluated.

RESULTS

The therapy outcomes of 71 patients improved, whereas 14 cases had worse outcomes. Age, preoperative cryptococcus count, and preoperative CSF protein levels were found to influence the surgical outcome. The nomogram exhibited exceptional predictive performance (area under the curve = 0.896, 95% confidence interval: 0.8292-0.9635). Internal validation confirmed the nomogram's excellent predictive capabilities. Moreover, decision curve analysis demonstrated the nomogram's practical clinical utility.

CONCLUSIONS

The surgical outcome of VP shunt procedures patients with non-HIV CM was associated with age, preoperative cryptococcal count, and preoperative CSF protein levels. We developed a nomogram that can be used to predict surgical outcomes in patients with non-HIV CM.

Subacute Hydrocephalus Revealing a Cryptococcus Infection in a Seven-Year-Old Child

Cryptococcal meningitis (CM) is the third most common neurological complication in immunocompromised patients and is usually associated with high rates of morbidity and mortality. The most common complication of CM is intracranial hypertension (ICH), and it constitutes a poor prognosis factor. This case report describes a case of subacute onset hydrocephalus revealing a human immunodeficiency virus (HIV)-associated CM in a seven-year-old girl requiring cerebrospinal fluid diversion and fungal treatment with a favorable outcome.

Cerebrospinal fluid shunting for the management of cryptococcal meningitis: a scoping review

Objective

This scoping review aimed to describe studies that evaluate the management of cryptococcal meningitis (CM) using cerebrospinal fluid (CSF) shunts, types of shunts used, and clinically relevant patient outcomes.

Methods

We searched in the following databases: PubMed, Web of Science/Core collection, Embase, the Cochrane Library, and clinicaltrials.gov on 1 April 2022. We included two-arm and one-arm cohort studies that evaluated clinically relevant patient outcomes. Case reports were used to describe the type of CSF shunts used and the rationale behind its selection. The selection and extraction processes were independently performed by two authors.

Results

This study included 20 cohort studies and 26 case reports. Only seven cohort studies compared two groups. Ventriculoperitoneal shunt was the most commonly used type of shunt (82.1%). The main indications for placing a shunt were persistently high opening pressure (57.1%) and persisting neurological symptoms or deterioration (54.3%). Cohort studies suggest that patients with shunt showed improvement in some outcomes such as neurological symptoms and hospital stay length. The most common shunt complications were post-operative fever (1-35.6%) and shunt obstruction (7-16%).

Conclusion

CSF shunts may improve some clinically relevant outcomes in patients with CM, but the evidence is very uncertain.

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.

Efficacy and safety of lenalidomide in HIV-associated cryptococcal meningitis patients with persistent intracranial inflammation: an open-label, single-arm, prospective interventional study

BACKGROUND

Patients with human immunodeficiency virus-associated cryptococcal meningitis (HIV-CM) have persistent intracranial inflammation despite negative cerebrospinal fluid (CSF) fungal cultures after optimal treatment for CM, which could be devastating for the central nervous system. However, a definitive treatment strategy for persistent intracranial inflammation despite optimal antifungal therapies is undefined.

METHODS

We identified 14 HIV-CM patients with persistent intracranial inflammation and conducted a 24-week, prospective, interventional study. All participants received lenalidomide (25 mg, p.o.) on days 1 to 21 of a 28-day cycle. Follow-up lasted for 24 weeks with visits at baseline and weeks 4, 8, 12, and 24. The primary endpoint was the change in clinical manifestations, routine CSF parameters, and MRI findings after lenalidomide treatment. An exploratory analysis was made on changes in cytokine levels in CSF. Safety and efficacy analyses were undertaken in patients who received at least one dose of lenalidomide.

RESULTS

Of 14 participants, 11 patients completed the 24 weeks of follow-up. Rapid clinical remission following lenalidomide therapy was observed. Clinical manifestations (fever, headache, altered mentation) were reversed fully by week-4 and remained stable during follow-up. A significant reduction in white blood cell (WBC) count in CSF was noted occurred at week-4 (P = 0.009). The median protein concentration in CSF decreased from 1.4 (0.7-3.2) g/L at baseline to 0.9 (0.6-1.4) at week-4 (P = 0.004). The median albumin concentration in CSF decreased from 79.2 (48.4-149.8) mg/L at baseline to 55.3 (38.3-89.0) mg/L at week-4 (P = 0.011). The WBC count, protein level, and albumin level in CSF remained stable and approached a normal range through week-24. There was no significant change in immunoglobulin-G, intracranial pressure (ICP), or chloride-ion concentration at each visit. Brain MRI demonstrated multiple lesions to be absorbed post-therapy. Levels of tumor necrosis factor-α granulocyte colony stimulating factor, interleukin (IL)-6, and IL-17A decreased significantly during 24-week follow-up. Two (14.3%) patients had mild skin rash, which resolved spontaneously. Lenalidomide-related serious adverse events were not observed.

CONCLUSION

Lenalidomide could improve persistent intracranial inflammation in HIV-CM patients significantly and was well tolerated without serious adverse events observed. And the additional randomized controlled study is required to further validate the finding.

Cryptococcal Meningitis in a Mexican Neurological Center

BACKGROUND

Cryptococcal meningitis, one of the most severe infections affecting the central nervous system, often involves severe neurological sequels and high mortality.

METHODS

A retrospective review was performed, including 76 cases admitted in a 10-year period at a neurological referral center in Mexico City. From 68 isolates, 52 fungal specimens were identified as part of the Cryptococcus neoformans var. neoformans complex, 15 as C. neoformans var gattii complex, and one as Cryptococcus non-neoformans/gattii.

RESULTS

Higher cryptococcal meningitis incidence and severity were found in HIV-infected men; other risk factors frequently observed were diabetes mellitus and labor exposure to poultry. The main clinical manifestations were subacute headache, cognitive alterations, and photophobia (exclusively in HIV patients). MRI was highly sensitive for pathologic findings such as meningeal enhancements and cryptococcomas, most of them associated to C. neoformans complex. Eleven patients developed severe brain vasculitis, as observed by transcranial Doppler. Hydrocephalus with intracranial hypertension was the most frequent complication.

CONCLUSIONS

One-half of the population died, and the rest had neurological sequels, mainly neuropsychiatric manifestations and secondary headaches. These patients developed severe functional limitations in performing daily activities in an independent manner.

Management of long-term cryptococcal meningitis neoformans in a surviving patient: A case report

Cryptococcal meningitis is a common fungal infection of the central nervous system with high mortality and disability rates. A prominent clinical manifestation is persistent and severe cranial hypertension, which is one of the most critical outcome determinants in patients with cryptococcal meningoencephalitis. Herein, we report and discuss a case of cryptococcal meningitis treated by an inadequate course of medical therapy and placement of a ventriculoperitoneal shunt in a patient who survived for more than 10 years.

Ventriculoperitoneal shunt is associated with increased cerebrospinal fluid protein level in HIV-infected cryptococcal meningitis patients

Background

The impact of ventriculoperitoneal shunt on cerebrospinal fluid (CSF) biochemical profiles in HIV-associated cryptococcal meningitis (HCM) patients remains unclear.

Methods

Twenty-nine HCM patients who underwent ventriculoperitoneal shunt (the VPS group) and 57 HCM patients who did not undergo ventriculoperitoneal shunt (the non-VPS group) were enrolled in this propensity score matching analysis. Demographic characteristics, symptoms, CSF biochemical profiles, and adverse events were compared between the two groups. The Kaplan–Meier method was used to analyze the survival rate. Univariate and multivariate logistic regression analyses were performed to identify the risk factors for increased CSF protein levels.

Results

After 24 weeks of treatment, the intracranial pressure was significantly lower in the VPS group than in the non-VPS group (mmH₂O; 155.0 [120.0–190.0] vs. 200.0 [142.5–290.0]; P = 0.025), and the rate of neuroimaging improvement was significantly higher in the VPS group (16/17 [94.1%] vs. 2/10 [20%]; P < 0.001). Furthermore, the 24-week cumulative survival rates were also significantly higher in the VPS group (96.6% vs. 83.5%, P = 0.025). Notably, the CSF protein levels were higher in the VPS group than in the non-VPS group at each examination time, and the CSF glucose was lower in the VPS group than in the non-VPS group even at the 12-week follow-up. In the multivariate analysis, we found that VPS placement was an independent risk factor for increased CSF protein (odds ratio [OR]: 27.8, 95% confidence interval [95% CI] 2.2–348.7; P = 0.010).

Conclusions

VPS decreased the intracranial pressure, improved neuroimaging radiology and reduced the 24-week mortality in HCM patients. However, VPS significantly altered the CSF profiles, which could lead to misdiagnosis of tuberculous meningitis and some of them were diagnosed with immune reconstitution inflammatory syndrome. Physicians should be aware of these changes in the CSF profiles of patients with HCM undergoing VPS.

The clinical characteristics and outcome of cryptococcal meningitis with AIDS in a tertiary hospital in China: an observational cohort study

BACKGROUND

Despite the profound impact of antiretroviral therapy in the control of AIDS mortality, central nervous system opportunistic infections remains a significant burden in AIDS patients. This retrospective study aims to elucidate the clinical characteristics, outcome and risk factors of cryptococcal meningitis (CM) poor prognosis in AIDS patients from a tertiary hospital in China.

METHODS

Clinical data from 128 patients admitted in Beijing Ditan Hospital, Capital Medical University from November 2008 to November 2017 was collected. The cohort was stratified based on treatment outcome (effective 79%, and ineffective 21%), and Multivariate Logistic regression analysis used to identify risk factors of poor disease prognosis.

RESULTS

Age, incidence of cerebral infarction, the proportion of consciousness disorder, and fasting plasma glucose was higher in the ineffective treatment group than the effective treatment group. The duration of treatment in the induction period of the ineffective group was significantly shorter than that of the effective group. Multivariate Logistic regression analysis indicated that the occurrence of cerebral hernia and consciousness disorder were risk factors for the prognosis of AIDS patients with CM infection, while the duration of treatment in the induction period was a indicative of a better prognosis in AIDS with CM infection complications. Finally, shunt decompression therapy correlated with a better disease outcome.

CONCLUSIONS

This retrospective study exposes the main risk factors associated with worse disease prognosis in AIDS patients with CM infection complications.

Surgical treatment and operation time in human immunodeficiency virus-negative cryptococcal meningitis

There are still no unified guidelines of surgical treatment and timing for human immunodeficiency virus (HIV)-negative patients with cryptococcal meningitis (CM).The clinical data and follow-up data were collected from HIV-negative CM patients in Xiangya Hospital of Central South University from January 2009 to November 2018, and 42 patients who were treated with surgical intervention were enrolled in the present study. These 42 patients were divided into ventriculoatrial (VA) group, ventriculoperitoneal group, external ventricle drainage (EVD) group, hydrocephalus (HYC) group, non-HYC group, EVD group, and non-EVD group (VA/ ventriculoperitoneal) according to different surgical procedures. Statistical analyses were conducted using SPSS (version 19.0, Chicago, IL).Signs of headache, fever, and loss of consciousness in the VA group were significantly improved compared with the EVD group at 1 week after operation (P < .05). The mortality rate of the VA group was significantly lower than that of the EVD group (P < .05). Moreover, male patients were more prone to have HYC (P < .05). Younger patients tended to develop HYC (P < .05). Cerebrospinal fluid sugar in the non-HYC group was significantly lower compared with the HYC group (P < .05). Time of CM-to-operation in the non-HYC group was markedly shorter compared with the HYC group (P < .01).VA procedure could be one of the first choices for the treatment of uncontrollable intracranial hypertension caused by CM. Severe uncontrollable headache, loss of consciousness, and cerebral hernia were indications of emergency surgery. Repeated headache, hearing impairment, and especially progressive loss of vision were indications of early surgery to avoid permanent damage to nerve functions of HIV-negative CM patients.

Ventriculoperitoneal shunt insertion in human immunodeficiency virus infected adults: a systematic review and meta-analysis

BACKGROUND

Hydrocephalus is a common, life threatening complication of human immunodeficiency virus (HIV)-related central nervous system opportunistic infection which can be treated by insertion of a ventriculoperitoneal shunt (VPS). In HIV-infected patients there is concern that VPS might be associated with unacceptably high mortality. To identify prognostic indicators, we aimed to compare survival and clinical outcome following VPS placement between all studied causes of hydrocephalus in HIV infected patients.

METHODS

The following electronic databases were searched: The Cochrane Central Register of Controlled Trials, MEDLINE (PubMed), EMBASE, CINAHL Plus, LILACS, Research Registry, the metaRegister of Controlled Trials, ClinicalTrials.gov, African Journals Online, and the OpenGrey database. We included observational studies of HIV-infected patients treated with VPS which reported of survival or clinical outcome. Data was extracted using standardised proformas. Risk of bias was assessed using validated domain-based tools.

RESULTS

Seven Hunderd twenty-three unique study records were screened. Nine observational studies were included. Three included a total of 75 patients with tuberculous meningitis (TBM) and six included a total of 49 patients with cryptococcal meningitis (CM). All of the CM and two of the TBM studies were of weak quality. One of the TBM studies was of moderate quality. One-month mortality ranged from 62.5-100% for CM and 33.3-61.9% for TBM. These pooled data were of low to very-low quality and was inadequate to support meta-analysis between aetiologies. Pooling of results from two studies with a total of 77 participants indicated that HIV-infected patients with TBM had higher risk of one-month mortality compared with HIV non-infected controls (odds ratio 3.03; 95% confidence-interval 1.13-8.12; p = 0.03).

CONCLUSIONS

The evidence base is currently inadequate to inform prognostication in VPS insertion in HIV-infected patients. A population-based prospective cohort study is required to address this, in the first instance.

Efficacy of ventriculoperitoneal shunting in patients with cryptococcal meningitis with intracranial hypertension

BACKGROUND

Ventriculoperitoneal (VP) shunting in cryptococcal meningitis (CM) patients with high intracranial pressure (ICP) has been studied extensively.

METHODS

A total of 74 CM patients with ICP were identified, including 27 patients with or without ventriculomegaly receiving VP shunting.

RESULTS

Through retrospective analysis, there was an obvious decline in ICP as well as Cryptococcus count after VP shunting. Damage to the cranial nerves was improved after the surgery. For those patients receiving VP shunting, there was an obvious decline in ICP as well as Cryptococcus count, with less usage of mannitol. Hydrocephalus or ventriculomegaly was improved, and both the clearance time of Cryptococcus and the hospitalization time were shortened (p<0.05). The complications of VP shunting were not common.

CONCLUSIONS

For patients diagnosed with CM and with apparent ICP, VP shunting can be considered regardless of whether there is damage to the cranial nerves or hydrocephaly.

Management of human immunodeficiency virus-associated cryptococcal meningitis: Current status and future directions

Cryptococcal meningitis (CM) is one of the most common opportunistic infections of acquired immunodeficiency syndrome (AIDS), as well as an important cause of hospitalisation and death. In recent years, the mortality of CM has remained high in HIV/AIDS population, with up to 30%, including within developed countries. The treatment usually encompasses controls of Cryptococcus, HIV, and increased intracranial pressure. Recent progress on the management of HIV-associated CM mainly centres in optimising induction regimens, looking for appropriate timing of initiating antiretroviral therapy and prevention of symptomatic onset and adverse consequences. This review compared several international guidelines combined with the results from some clinical researches to illustrate the similarities, differences and potential in CM treatment. The present practice is still far from satisfactory, and there remains much to explore due to our limited understanding of the pathogenesis of HIV-associated CM. Thus, screening and monitoring should be strengthened, and better therapies in line with the actual situation of each country should be discovered.

Intraventricular cryptococcoma mimicking a neoplastic lesion in an immunocompetent patient with hydrocephalus: A case report

Background:

The aim of this study is to highlight the importance of cryptococcosis as one of the most common fungal infections of the central nervous system, stressing the consideration of a cryptococcoma within the list of differential diagnosis of intraventricular masses in immunocompetent hosts.

Case Description:

We present the case of an immunocompetent 41-year-old female from Philippines with an intraventricular cryptococcoma due to Cryptococcus neoformans, mimicking an intraventricular primary brain tumor, who had hydrocephalus. She was approached as having a neoplastic lesion and underwent surgical resection plus third ventriculostomy through endoscopy. Later in her evolution, we realized the infectious nature of the lesion, and antifungal systemic therapy was initiated. In the end, she needed the placement of a ventriculoperitoneal shunt to maintain a good neurologic status. Despite all our efforts, she had a fatal outcome due to various complications.

Conclusion:

Our case is the first intraventricular cryptococcoma due to C. neoformans, as far as we know, to be reported in English, German, or Spanish literature. Our report stresses the importance to consider this kind of infection in immunocompetent patients, to raise the level of suspicion of this diagnosis, and to know the complications and management options.

Factors Associated With Ventriculoperitoneal Shunt Placement in Patients With Cryptococcal Meningitis

Objective

Increased intracranial pressure (ICP) is an important complication of cryptococcal meningitis (CM) and impacts morbidity and mortality. Factors associated with permanent ventriculoperitoneal (VP) shunt placement are poorly characterized.

Method

We conducted a retrospective cohort study of patients with CM at the University of Alabama at Birmingham from 1996 through 2015. Characteristics of patients at time of CM diagnosis who did and did not receive a VP shunt were compared with use of the 2-group chi-square test or Fisher exact test for categorical variables and the 2-group t test for continuous variables. Stepwise logistic regression analysis was used to determine predictors of shunt placement.

Results

Of 422 patients with cryptococcosis, 257 (60.9%) had CM. Mean age was 47.7 years, 71.6% were male, and 44.4% were African American. The most common underlying conditions were HIV (42.4%), solid organ transplantation (29.6%), and corticosteroid use (34.2%). Forty-four (17.1%) received a VP shunt a median of 17 days (range, 1-320 days) post-diagnosis. By multivariable analysis, baseline opening pressure >30 cm H₂O (OR, 9.4; 95% CI, 3.0, 28.8; P < .0001), being a normal host (OR, 6.3; 95% CI, 1.5, 26.1; P = .011) and hydrocephalus (OR, 4.9, 95% CI, 1.3, 17.9); P = .017) were associated with increased odds of shunting (Table 2). In contrast, age (OR, 0.96; 95% CI, 0.92, 0.99; P = .037) and male gender (OR, 0.18; 95% CI, 0.06, 0.55; P = .023) were associated with decreased odds of shunting.

Conclusions

Identification of factors at time of CM diagnosis associated with need for permanent VP shunt placement may allow for earlier, more aggressive treatment and potentially improve outcomes associated with increased ICP from cryptococcal meningitis.

Ventriculoperitoneal shunts in non-HIV cryptococcal meningitis

Background

Persistent and uncontrollable intracranial hypertension (ICH) and difficulty in reducing Cryptococcus count are severe problems in cryptococcal meningitis (CM) patients. The therapeutic effects of ventriculoperitoneal shunts (VPS) in non-HIV CM patients are not fully known, and the procedure is somewhat unusual. Here, our study offers a review to investigate the role of VPS in non-HIV CM.

Methods

We retrospectively collected data on 23 non-HIV CM patients with and without ventriculomegaly from 2010 to 2016. Their demographic data, clinical manifestations, cerebrospinal fluid (CSF) features and outcomes were analysed.

Results

We found that non-HIV CM patients without ventriculomegaly were older, had earlier treatment times and had shorter symptom durations than CM patients with ventriculomegaly. In both groups, headache, vomiting, fever and loss of vision were the most common clinical features. CSF pressure and Cryptococcus count were significantly decreased after operation. VPS could provide sustained relief from ICH symptoms such as headache. 13% of patients had poor outcomes because of serious underlying disease, while 87% of patients had good outcomes.

Conclusions

The use of a VPS is helpful in decreasing ICH and fungal overload in non-HIV CM patients, and VPS should be performed before CM patients present with symptoms of severe neurological deficit.

Update on the application of optic nerve sheath fenestration

BACKGROUND

With the ongoing development of surgical procedures and instruments, the safety of optic nerve sheath fenestration (ONSF) has been improved.

OBJECTIVE

Through the past three decades, progress has been made in preventing visual loss from chronic optic nerve swelling in idiopathic intracranial hypertension (IIH), secondary intracranial hypertension and local optic nerve diseases. We now review the updated application of ONSF in those diseases.

METHODS

The application of ONSF in papilledema due to IIH, secondary intracranial hypertension to cerebral venous sinus occlusion, Cryptococcal meningitis, and intracranial mass or tumors is reviewed. Additionally, the potential benefits of ONSF in local optic neuropathy from optic nerve sheath meningioma, optic nerve drusen, traumatic optic neuropathy and optic nerve/sheath biopsy are also described.

RESULTS

Although ONSF has little or no effect on intracranial pressure, it is a safe, relative easy and effective surgical procedure to prevent or reverse visual loss in IIH. When other treatment modalities fail to timely protect vision, ONSF can be useful in protecting visual function or delay visual loss in secondary intracranial hypertension.

CONCLUSION

We recommend that ONSF should be considered as a meaningful alternative or an adjunct therapy to reduce or delay the visual morbidity of these diseases, although the use of ONSF for some of them remains controversial.

Cryptococcal disease in the solid organ transplant setting: review of clinical aspects with a discussion of asymptomatic cryptococcal antigenemia

PURPOSE OF REVIEW

Cryptococcal infections are an important cause of morbidity and mortality in solid organ transplant patients. Here, we review the microbiology, epidemiology, clinical course, treatment, and outcomes of Cryptococcus in solid organ transplant recipients.

RECENT FINDINGS

We identify the unique findings in solid organ transplant patients when compared to other immunocompromised patients such as those with HIV. We also describe our experience and outcomes with regard to solid organ transplant patients who do not have positive fungal cultures, but cryptococcal antigen positivity and concern for cryptococcal disease.

SUMMARY

Our review will highlight the importance of these new diagnostic techniques in those with Cryptococcus and solid organ transplant, which will be the subject of new research.

Geometrical Distribution of Cryptococcus neoformans Mediates Flower-Like Biofilm Development

Microbial biofilms are highly structured and dynamic communities in which phenotypic diversification allows microorganisms to adapt to different environments under distinct conditions. The environmentally ubiquitous pathogen Cryptococcus neoformans colonizes many niches of the human body and implanted medical devices in the form of biofilms, an important virulence factor. A new approach was used to characterize the underlying geometrical distribution of C. neoformans cells during the adhesion stage of biofilm formation. Geometrical aspects of adhered cells were calculated from the Delaunay triangulation and Voronoi diagram obtained from scanning electron microscopy images (SEM). A correlation between increased biofilm formation and higher ordering of the underlying cell distribution was found. Mature biofilm aggregates were analyzed by applying an adapted protocol developed for ultrastructure visualization of cryptococcal cells by SEM. Flower-like clusters consisting of cells embedded in a dense layer of extracellular matrix were observed as well as distinct levels of spatial organization: adhered cells, clusters of cells and community of clusters. The results add insights into yeast motility during the dispersion stage of biofilm formation. This study highlights the importance of cellular organization for biofilm growth and presents a novel application of the geometrical method of analysis.

The use of mannitol in HIV-infected patients with symptomatic cryptococcal meningitis

Cryptococcal meningitis (CM) is a common opportunistic infection with a high mortality rate in human immunodeficiency virus (HIV)-infected patients. It is unclear whether mannitol could be used to manage neurological symptoms in HIV-associated CM. Here, we retrospectively analyzed the clinical data of 33 patients with HIV-associated symptomatic CM at our hospital where mannitol was used to relieve neurologic symptoms. With the empirical mannitol therapy, patients had a median of 2 episodes (range, 1-6 episodes) of headaches the day at the starting of anti-cryptococcal therapy. The median score of pain intensity assessed by numerical rating scales was 7-point (range, 4-8 points). After the administration of mannitol, the score of pain intensity was reduced to 3-point or less. Three weeks after anti-cryptococcal therapy, 75.8% (25/33) of the patients did not report headaches. During the initial 3 weeks of anti-cryptococcal therapy, 13 patients had a total of 42 episodes of seizures. 97.6% (41/42) of the episodes of seizures were controlled after the administration of mannitol. Overall, 87.9% (29/33) of the patients survived more than 10 weeks without the need of therapeutic cerebrospinal fluid drainage. Mannitol was used for median of 26 days (range, 1-85 days) in these 29 patients. One patient had permanent vision loss. This study indicates that mannitol may possibly relieve neurologic symptoms in HIV-associated CM. It is worth re-revaluating the role of mannitol administration as a symptom control strategy in mild cases of HIV-associated CM.