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Govender NP, Meintjes G, Mangena P, Nel J, Potgieter S, Reddy D, Rabie H, Wilson D, Black J, Boulware D, Boyles T, Chiller T, Dawood H, Dlamini S, Harrison TS, Ive P, Jarvis J, Karstaedt A, Madua MC, Menezes C, Moosa MYS, Motlekar Z, Shroufi A, Stacey SL, Tsitsi M, van Cutsem G, Variava E, Venter M, Wake R. Southern African HIV Clinicians Society guideline for the prevention, diagnosis and management of cryptococcal disease among HIV-infected persons: 2019 update. South Afr J HIV Med 2019; 20:1030. [PMID: 32201629 PMCID: PMC7081625 DOI: 10.4102/sajhivmed.v20i1.1030] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 09/12/2019] [Indexed: 02/06/2023] Open
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Pasquier E, Kunda J, De Beaudrap P, Loyse A, Temfack E, Molloy SF, Harrison TS, Lortholary O. Long-term Mortality and Disability in Cryptococcal Meningitis: A Systematic Literature Review. Clin Infect Dis 2019; 66:1122-1132. [PMID: 29028957 DOI: 10.1093/cid/cix870] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2017] [Accepted: 10/03/2017] [Indexed: 11/14/2022] Open
Abstract
Cryptococcal meningitis (CM) is the primary cause of meningitis in adults with human immunodeficiency virus (HIV) infection and an emerging disease in HIV-seronegative individuals. No literature review has studied the long-term outcome of CM. We performed a systematic review on the long-term (≥3-month) impact of CM (Cryptococcus neoformans and Cryptococcus gattii) on mortality and disability in HIV-infected and non-HIV-infected adults. Although the quality of current evidence is limited, the long-term impact of CM on survival and disability seems to be high. One-year mortality ranged from 13% in an Australian non-HIV-infected C. gattii-infected cohort to 78% in a Malawian HIV-infected cohort treated with fluconazole monotherapy. One-year impairment proportions among survivors ranged from 19% in an Australian C. gattii cohort to >70% in a Taiwanese non-HIV- and HIV-infected cohorts. Ongoing early therapeutic interventions, early detection of impairments and access to rehabilitation services may significantly improve patients' survival and quality of life.
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Ellis JP, Gaskell K, Peirse M, Gormley J, Kalata N, Burgess PI, Mopamboli P, Manda CA, Kiire CA, Maccormick I, Gondwe E, Molloy S, Harrison TS, Lalloo DG, Heyderman RS. Ophthalmic features of HIV associated cryptococcal meningitis in Malawian Adults: an observational study. Wellcome Open Res 2019. [DOI: 10.12688/wellcomeopenres.15067.2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background: Cryptococcal meningitis (CM) is the commonest neurological complication in patients with advanced HIV. Visual disturbance is a frequent presenting symptom. Papilloedema is commonly reported but other ophthalmic findings are not well described. Methods: We performed an observational study comparing severely immunocompromised HIV-infected patients with and without CM to determine the nature and prevalence of retinal pathology attributable to CM. 70 adult patients were enrolled in Blantyre Malawi, 35 with CM and 35 HIV-infected patients without CM. Results: 79% (19/24) of CM patients examined on day one had evidence of retinal abnormalities compared to 17% (6/35) of HIV-infected controls (p <0.001). In the CM group, retinal whitening was the commonest abnormality (50%), followed by optic disc swelling (29%), haemorrhage (25%) and vascular abnormalities (7%). Retinal whitening was the only abnormality observed in the comparator group (17%). In CM, there was no significant difference between those with and without retinal abnormalities in fungal burden (13,550 cfu/ml vs. 9,150 cfu/ml; p = 0.65), CD4 count (28 cells/µl vs. 76 cells/µl; p = 0.79) or CSF opening pressure (21cm H20 vs. 27cm H20; p = 0.5). There was no association between presence/absence of retinal abnormalities and death (40% 10-week mortality vs. 26%; p = 0.6). Conclusions: Whether the presence of CM retinopathy could be used as a marker of disease severity warrants further investigation. The observed ophthalmic findings provide a descriptive framework for CM retinopathy to be utilised in future CM studies. Trial registration: ISRCTN (ISRCTN45035509) 19/06/2012.
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Boyer-Chammard T, Temfack E, Alanio A, Jarvis JN, Harrison TS, Lortholary O. Recent advances in managing HIV-associated cryptococcal meningitis. F1000Res 2019; 8:F1000 Faculty Rev-743. [PMID: 31275560 PMCID: PMC6544127 DOI: 10.12688/f1000research.17673.1] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 05/17/2019] [Indexed: 12/22/2022] Open
Abstract
The recent development of highly sensitive and specific point-of-care tests has made it possible to diagnose HIV-associated cryptococcal meningitis within minutes. However, diagnostic advances have not been matched by new antifungal drugs and treatment still relies on old off-patent drugs: amphotericin B, flucytosine and fluconazole. Cryptococcal meningitis treatment is divided in three phases: induction, consolidation and maintenance. The induction phase, aimed at drastically reducing cerebrospinal fluid fungal burden, is key for patient survival. The major challenge in cryptococcal meningitis management has been the optimisation of induction phase treatment using the limited number of available medications, and major progress has recently been made. In this review, we summarise data from key trials which form the basis of current treatment recommendations for HIV-associated cryptococcal meningitis.
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Ellis JP, Gaskell K, Peirse M, Gormley J, Kalata N, Burgess PI, Mopamboli P, Manda CA, Kiire CA, Maccormick I, Gondwe E, Molloy S, Harrison TS, Lalloo DG, Heyderman RS. Ophthalmic features of HIV associated cryptococcal meningitis in Malawian Adults: an observational study. Wellcome Open Res 2019. [DOI: 10.12688/wellcomeopenres.15067.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background: Cryptococcal meningitis (CM) is the commonest neurological complication in patients with advanced HIV. Visual disturbance is a frequent presenting symptom. Papilloedema is commonly reported but other ophthalmic findings are not well described. Methods: We performed an observational study comparing severely immunocompromised HIV-infected patients with and without CM to determine the nature and prevalence of retinal pathology attributable to CM. 70 adult patients were enrolled in Blantyre Malawi, 35 with CM and 35 HIV-infected patients without CM. Results: 79% (19/24) of CM patients examined on day one had evidence of retinal abnormalities compared to 17% (6/35) of HIV-infected controls (p <0.001). In the CM group, retinal whitening was the commonest abnormality (50%), followed by optic disc swelling (29%), haemorrhage (25%) and vascular abnormalities (7%). Retinal whitening was the only abnormality observed in the comparator group (17%). In CM, there was no significant difference between those with and without retinal abnormalities in fungal burden (13,550 cfu/ml vs. 9,150 cfu/ml; p = 0.65), CD4 count (28 cells/µl vs. 76 cells/µl; p = 0.79) or CSF opening pressure (21cm H20 vs. 27cm H20; p = 0.5). There was no association between presence/absence of retinal abnormalities and death (40% 10-week mortality vs. 26%; p = 0.6). Conclusions: Whether the presence of CM retinopathy could be used as a marker of disease severity warrants further investigation. The observed ophthalmic findings provide a descriptive framework for CM retinopathy to be utilised in future CM studies. Trial registration: ISRCTN (ISRCTN45035509) 19/06/2012.
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Ponatshego PL, Lawrence DS, Youssouf N, Molloy SF, Alufandika M, Bango F, Boulware DR, Chawinga C, Dziwani E, Gondwe E, Hlupeni A, Hosseinipour MC, Kanyama C, Meya DB, Mosepele M, Muthoga C, Muzoora CK, Mwandumba H, Ndhlovu CE, Rajasingham R, Sayed S, Shamu S, Tsholo K, Tugume L, Williams D, Maheswaran H, Shiri T, Boyer-Chammard T, Loyse A, Chen T, Wang D, Lortholary O, Lalloo DG, Meintjes G, Jaffar S, Harrison TS, Jarvis JN, Niessen LW. AMBIsome Therapy Induction OptimisatioN (AMBITION): High dose AmBisome for cryptococcal meningitis induction therapy in sub-Saharan Africa: economic evaluation protocol for a randomised controlled trial-based equivalence study. BMJ Open 2019; 9:e026288. [PMID: 30940760 PMCID: PMC6500286 DOI: 10.1136/bmjopen-2018-026288] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
INTRODUCTION Cryptococcal meningitis is responsible for around 15% of all HIV-related deaths globally. Conventional treatment courses with amphotericin B require prolonged hospitalisation and are associated with multiple toxicities and poor outcomes. A phase II study has shown that a single high dose of liposomal amphotericin may be comparable to standard treatment. We propose a phase III clinical endpoint trial comparing single, high-dose liposomal amphotericin with the WHO recommended first-line treatment at six sites across five counties. An economic analysis is essential to support wide-scale implementation. METHODS AND ANALYSIS Country-specific economic evaluation tools will be developed across the five country settings. Details of patient and household out-of-pocket expenses and any catastrophic healthcare expenditure incurred will be collected via interviews from trial patients. Health service patient costs and related household expenditure in both arms will be compared over the trial period in a probabilistic approach, using Monte Carlo bootstrapping methods. Costing information and number of life-years survived will be used as the input to a decision-analytic model to assess the cost-effectiveness of a single, high-dose liposomal amphotericin to the standard treatment. In addition, these results will be compared with a historical cohort from another clinical trial. ETHICS AND DISSEMINATION The AMBIsome Therapy Induction OptimisatioN (AMBITION) trial has been evaluated and approved by the London School of Hygiene and Tropical Medicine, University of Botswana, Malawi National Health Sciences, University of Cape Town, Mulago Hospital and Zimbabwe Medical Research Council research ethics committees. All participants will provide written informed consent or if lacking capacity will have consent provided by a proxy. The findings of this economic analysis, part of the AMBITION trial, will be disseminated through peer-reviewed publications and at international and country-level policy meetings. TRIAL REGISTRATION ISRCTN 7250 9687; Pre-results.
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Loyse A, Burry J, Cohn J, Ford N, Chiller T, Ribeiro I, Koulla-Shiro S, Mghamba J, Ramadhani A, Nyirenda R, Aliyu SH, Wilson D, Le T, Oladele R, Lesikari S, Muzoora C, Kalata N, Temfack E, Mapoure Y, Sini V, Chanda D, Shimwela M, Lakhi S, Ngoma J, Gondwe-Chunda L, Perfect C, Shroufi A, Andrieux-Meyer I, Chan A, Schutz C, Hosseinipour M, Van der Horst C, Klausner JD, Boulware DR, Heyderman R, Lalloo D, Day J, Jarvis JN, Rodrigues M, Jaffar S, Denning D, Migone C, Doherty M, Lortholary O, Dromer F, Stack M, Molloy SF, Bicanic T, van Oosterhout J, Mwaba P, Kanyama C, Kouanfack C, Mfinanga S, Govender N, Harrison TS. Leave no one behind: response to new evidence and guidelines for the management of cryptococcal meningitis in low-income and middle-income countries. THE LANCET. INFECTIOUS DISEASES 2019; 19:e143-e147. [PMID: 30344084 DOI: 10.1016/s1473-3099(18)30493-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2018] [Revised: 07/13/2018] [Accepted: 07/26/2018] [Indexed: 02/01/2023]
Abstract
In 2018, WHO issued guidelines for the diagnosis, prevention, and management of HIV-related cryptococcal disease. Two strategies are recommended to reduce the high mortality associated with HIV-related cryptococcal meningitis in low-income and middle-income countries (LMICs): optimised combination therapies for confirmed meningitis cases and cryptococcal antigen screening programmes for ambulatory people living with HIV who access care. WHO's preferred therapy for the treatment of HIV-related cryptococcal meningitis in LMICs is 1 week of amphotericin B plus flucytosine, and the alternative therapy is 2 weeks of fluconazole plus flucytosine. In the ACTA trial, 1-week (short course) amphotericin B plus flucytosine resulted in a 10-week mortality of 24% (95% CI -16 to 32) and 2 weeks of fluconazole and flucytosine resulted in a 10-week mortality of 35% (95% CI -29 to 41). However, with widely used fluconazole monotherapy, mortality because of HIV-related cryptococcal meningitis is approximately 70% in many African LMIC settings. Therefore, the potential to transform the management of HIV-related cryptococcal meningitis in resource-limited settings is substantial. Sustainable access to essential medicines, including flucytosine and amphotericin B, in LMICs is paramount and the focus of this Personal View.
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Stone NR, Rhodes J, Fisher MC, Mfinanga S, Kivuyo S, Rugemalila J, Segal ES, Needleman L, Molloy SF, Kwon-Chung J, Harrison TS, Hope W, Berman J, Bicanic T. Dynamic ploidy changes drive fluconazole resistance in human cryptococcal meningitis. J Clin Invest 2019; 129:999-1014. [PMID: 30688656 PMCID: PMC6391087 DOI: 10.1172/jci124516] [Citation(s) in RCA: 93] [Impact Index Per Article: 18.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 11/30/2018] [Indexed: 01/17/2023] Open
Abstract
BACKGROUND Cryptococcal meningitis (CM) causes an estimated 180,000 deaths annually, predominantly in sub-Saharan Africa, where most patients receive fluconazole (FLC) monotherapy. While relapse after FLC monotherapy with resistant strains is frequently observed, the mechanisms and impact of emergence of FLC resistance in human CM are poorly understood. Heteroresistance (HetR) - a resistant subpopulation within a susceptible strain - is a recently described phenomenon in Cryptococcus neoformans (Cn) and Cryptococcus gattii (Cg), the significance of which has not previously been studied in humans. METHODS A cohort of 20 patients with HIV-associated CM in Tanzania was prospectively observed during therapy with either FLC monotherapy or in combination with flucytosine (5FC). Total and resistant subpopulations of Cryptococcus spp. were quantified directly from patient cerebrospinal fluid (CSF). Stored isolates underwent whole genome sequencing and phenotypic characterization. RESULTS Heteroresistance was detectable in Cryptococcus spp. in the CSF of all patients at baseline (i.e., prior to initiation of therapy). During FLC monotherapy, the proportion of resistant colonies in the CSF increased during the first 2 weeks of treatment. In contrast, no resistant subpopulation was detectable in CSF by day 14 in those receiving a combination of FLC and 5FC. Genomic analysis revealed high rates of aneuploidy in heteroresistant colonies as well as in relapse isolates, with chromosome 1 (Chr1) disomy predominating. This is apparently due to the presence on Chr1 of ERG11, which is the FLC drug target, and AFR1, which encodes a drug efflux pump. In vitro efflux levels positively correlated with the level of heteroresistance. CONCLUSION Our findings demonstrate for what we believe is the first time the presence and emergence of aneuploidy-driven FLC heteroresistance in human CM, association of efflux levels with heteroresistance, and the successful suppression of heteroresistance with 5FC/FLC combination therapy. FUNDING This work was supported by the Wellcome Trust Strategic Award for Medical Mycology and Fungal Immunology 097377/Z/11/Z and the Daniel Turnberg Travel Fellowship.
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Jarvis JN, Leeme TB, Molefi M, Chofle AA, Bidwell G, Tsholo K, Tlhako N, Mawoko N, Patel RKK, Tenforde MW, Muthoga C, Bisson GP, Kidola J, Changalucha J, Lawrence D, Jaffar S, Hope W, Molloy SF, Harrison TS. Short-course High-dose Liposomal Amphotericin B for Human Immunodeficiency Virus-associated Cryptococcal Meningitis: A Phase 2 Randomized Controlled Trial. Clin Infect Dis 2019; 68:393-401. [PMID: 29945252 PMCID: PMC6336908 DOI: 10.1093/cid/ciy515] [Citation(s) in RCA: 55] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 06/18/2018] [Indexed: 01/03/2023] Open
Abstract
Background We performed a phase 2 noninferiority trial examining the early fungicidal activity (EFA) of 3 short-course, high-dose liposomal amphotericin B (L-AmB) regimens for cryptococcal meningitis (CM) in Tanzania and Botswana. Methods Human immunodeficiency virus (HIV)-infected adults with CM were randomized to (i) L-AmB 10 mg/kg on day 1 (single dose); (ii) L-AmB 10 mg/kg on day 1 and 5 mg/kg on day 3 (2 doses); (iii) L-AmB 10 mg/kg on day 1 and 5 mg/kg on days 3 and 7 (3 doses); or (iv) L-AmB 3 mg/kg/day for 14 days (control). All patients also received oral fluconazole 1200 mg/day for 14 days. Primary endpoint was mean rate of clearance of cerebrospinal fluid cryptococcal infection (EFA). Noninferiority was defined as an upper limit of the 2-sided 95% confidence interval (CI) of difference in EFA between intervention and control <0.2 log10 colony-forming units (CFU)/mL/day. Results Eighty participants were enrolled. EFA for daily L-AmB was -0.41 log10 CFU/mL/day (standard deviation, 0.11; n = 17). Difference in mean EFA from control was -0.11 (95% CI, -.29 to .07) log10 CFU/mL/day faster with single dose (n = 16); -0.05 (95% CI, -.20 to .10) log10 CFU/mL/day faster with 2 doses (n = 18); and -0.13 (95% CI, -.35 to .09) log10 CFU/mL/day faster with 3 doses (n = 18). EFA in all short-course arms was noninferior to control. Ten-week mortality was 29% (n = 23) with no statistical difference between arms. All arms were well tolerated. Conclusions Single-dose 10 mg/kg L-AmB was well tolerated and led to noninferior EFA compared to 14 days of 3 mg/kg/day L-AmB in HIV-associated CM. Induction based on a single 10 mg/kg L-AmB dose is being taken forward to a phase 3 clinical endpoint trial. Clinical Trials Registration ISRCTN 10248064.
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Lawrence DS, Youssouf N, Molloy SF, Alanio A, Alufandika M, Boulware DR, Boyer-Chammard T, Chen T, Dromer F, Hlupeni A, Hope W, Hosseinipour MC, Kanyama C, Lortholary O, Loyse A, Meya DB, Mosepele M, Muzoora C, Mwandumba HC, Ndhlovu CE, Niessen L, Schutz C, Stott KE, Wang D, Lalloo DG, Meintjes G, Jaffar S, Harrison TS, Jarvis JN. Correction to: AMBIsome Therapy Induction OptimisatioN (AMBITION): High Dose AmBisome for Cryptococcal Meningitis Induction Therapy in sub-Saharan Africa: Study Protocol for a Phase 3 Randomised Controlled Non-Inferiority Trial. Trials 2019; 20:48. [PMID: 30642386 PMCID: PMC6332521 DOI: 10.1186/s13063-018-3155-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Accepted: 12/28/2018] [Indexed: 11/24/2022] Open
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Lawrence DS, Youssouf N, Molloy SLF, Alanio A, Alufandika M, Boulware DR, Boyer-Chammard T, Chen T, Dromer F, Hlupeni A, Hope W, Hosseinipour MC, Kanyama C, Lortholary O, Loyse A, Meya DB, Mosepele M, Muzoora C, Mwandumba HC, Ndhlovu CE, Niessen L, Schutz C, Stott KE, Wang D, Lalloo DG, Meintjes G, Jaffar S, Harrison TS, Jarvis JN. AMBIsome Therapy Induction OptimisatioN (AMBITION): High Dose AmBisome for Cryptococcal Meningitis Induction Therapy in sub-Saharan Africa: Study Protocol for a Phase 3 Randomised Controlled Non-Inferiority Trial. Trials 2018; 19:649. [PMID: 30470259 PMCID: PMC6251219 DOI: 10.1186/s13063-018-3026-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Accepted: 10/29/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Cryptococcal meningitis (CM) is a major cause of mortality in HIV programmes in Africa despite increasing access to antiretroviral therapy (ART). Mortality is driven in part by limited availability of amphotericin-based treatment, drug-induced toxicities of amphotericin B deoxycholate and prolonged hospital admissions. A single, high-dose of liposomal amphotericin (L-AmB, Ambisome) on a fluconazole backbone has been reported as non-inferior to 14 days of standard dose L-AmB in reducing fungal burden. This trial examines whether single, high-dose L-AmB given with high-dose fluconazole and flucytosine is non-inferior to a seven-day course of amphotericin B deoxycholate plus flucytosine (the current World Health Organization [WHO] recommended treatment regimen). METHODS An open-label phase III randomised controlled non-inferiority trial conducted in five countries in sub-Saharan Africa: Botswana, Malawi, South Africa, Uganda and Zimbabwe. The trial will compare CM induction therapy with (1) a single dose (10 mg/kg) of L-AmB given with 14 days of fluconazole (1200 mg/day) and flucytosine (100 mg/kg/day) to (2) seven days amphotericin B deoxycholate (1 mg/kg/day) given alongside seven days of flucytosine (100 mg/kg/day) followed by seven days of fluconazole (1200 mg/day). The primary endpoint is all-cause mortality at ten weeks with a non-inferiority margin of 10% and 90% power. Secondary endpoints are early fungicidal activity, proportion of grade III/IV adverse events, pharmacokinetic parameters and pharmacokinetic/pharmacodynamic associations, health service costs, all-cause mortality within the first two and four weeks, all-cause mortality within the first ten weeks (superiority analysis) and rates of CM relapse, immune reconstitution inflammatory syndrome and disability at ten weeks. A total of 850 patients aged ≥ 18 years with a first episode of HIV-associated CM will be enrolled (425 randomised to each arm). All patients will be followed for 16 weeks. All patients will receive consolidation therapy with fluconazole 800 mg/day to complete ten weeks of treatment, followed by fluconazole maintenance and ART as per local guidance. DISCUSSION A safe, sustainable and easy to administer regimen of L-AmB that is non-inferior to seven days of daily amphotericin B deoxycholate therapy may reduce the number of adverse events seen in patients treated with amphotericin B deoxycholate and shorten hospital admissions, providing a highly favourable and implementable alternative to the current WHO recommended first-line treatment. TRIAL REGISTRATION ISRCTN, ISRCTN72509687 . Registered on 13 July 2017.
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Ellis JP, Kalata N, Joekes EC, Kampondeni S, Benjamin LA, Harrison TS, Lalloo DG, Heyderman RS. Ischemic stroke as a complication of cryptococcal meningitis and immune reconstitution inflammatory syndrome: a case report. BMC Infect Dis 2018; 18:520. [PMID: 30326861 PMCID: PMC6192067 DOI: 10.1186/s12879-018-3386-0] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 09/14/2018] [Indexed: 01/21/2023] Open
Abstract
Background Cryptococcal meningitis remains the leading cause of adult meningitis in Sub-Saharan Africa. Immune Reconstitution Inflammatory Syndrome (IRIS) following anti-retroviral therapy (ART) initiation is an important complication. Here we report the first documented case of a IRIS reaction presenting as an ischemic stroke. Case presentation A 38 year old newly diagnosed HIV-infected, ART naive Malawian male presented to a tertiary referral hospital in Blantyre, Malawi with a 2 week history of headache. A diagnosis of cryptococcal meningitis was made and the patient was started on 1200 mg fluconazole once daily and flucytosine 25 mg/kg four times daily as part of the Advancing Cryptococcal Treatment for Africa (ACTA) clinical trial. There was an initial clinical and microbiological response to anti-fungal treatment and anti-retroviral therapy was started at week 4. The patient re-presented 16 days later with recurrence of headache, fever, and a sudden onset of left sided weakness in the context of rapid immune reconstitution; peripheral CD4 count had increased from a baseline of 29 cells/μl to 198 cells/μl. Recurrence of cryptococcal meningitis was excluded through CSF examination and fungal culture. Magnetic Resonance Imaging (MRI) of the brain demonstrated multi-focal DWI (diffusion weighted imaging) positive lesions consistent with an ischemic stroke. Given the temporal relationship to ART initiation, these MRI findings in the context of sterile CSF with raised CSF protein and a rapid immune reconstitution, following an earlier favorable response to treatment is most consistent with a paradoxical Immune Reconstitution Inflammatory Syndrome. Conclusions Stroke is an increasing cause of morbidity and mortality amongst HIV infected persons. Ischemic stroke is a recognized complication of cryptococcal meningitis in the acute phase and is thought to be mediated by an infectious vasculitis. This is the first time an ischemic stroke has been described as part of a paradoxical IRIS reaction. This report adds to the spectrum of clinical IRIS presentations recognized and highlights to clinicians the potential complications encountered at ART initiation in severely immunocompromised patients. Electronic supplementary material The online version of this article (10.1186/s12879-018-3386-0) contains supplementary material, which is available to authorized users.
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Molloy SF, Bradley J, Karunaharan N, Mputu M, Stone N, Phulusa J, Chawinga C, Gaskell K, Segula D, Ming D, Peirse M, Chanda D, Lakhi S, Loyse A, Kanyama C, Heyderman RS, Harrison TS. Effect of oral fluconazole 1200 mg/day on QT interval in African adults with HIV-associated cryptococcal meningitis. AIDS 2018; 32:2259-2261. [PMID: 30102652 PMCID: PMC6150187 DOI: 10.1097/qad.0000000000001961] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2018] [Accepted: 06/27/2018] [Indexed: 11/25/2022]
Abstract
: We assessed the effect of fluconazole 1200 mg/day on the QT interval in cryptococcal meningitis patients. Mean corrected QT (QTc) change from baseline to day 7 was 10.1 ms (IQR: -28 to 46 ms) in the fluconazole treatment group and -12.6 ms (IQR: -39 to 13.5 ms) in those not taking fluconazole (P = 0.04). No significant increase in QTc measurements over 500 ms was observed with fluconazole. Nevertheless, it remains important to correct any electrolyte imbalance and avoid concomitant drugs that may increase QTc.
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Wake RM, Jarvis JN, Harrison TS, Govender NP. Brief Report: Point of Care Cryptococcal Antigen Screening: Pipetting Finger-Prick Blood Improves Performance of Immunomycologics Lateral Flow Assay. J Acquir Immune Defic Syndr 2018; 78:574-578. [PMID: 29771787 PMCID: PMC6381996 DOI: 10.1097/qai.0000000000001721] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Cryptococcal antigen (CrAg) screening at the point of care could improve cryptococcal meningitis prevention where laboratory resources are limited. We evaluated the accuracy of Immunomycologics (IMMY, Norman, OK) CrAg lateral flow assay (LFA) using different techniques at point of care. SETTING Two tertiary-level hospitals in Johannesburg and a community health clinic in Soweto, South Africa. METHODS A case-control diagnostic validation study and a prospective clinic-based implementation study using the IMMY CrAg LFA on finger-prick blood. Accuracy, using direct application of LFA to sample, or pipette to transfer sample to diluent, and reading after 10 and 20 minutes, was compared with laboratory-based plasma testing. RESULTS The validation study tested 64 CrAg-positive and 152 CrAg-negative patients with no symptoms or signs of meningitis, identified by routine laboratory screening, recruited by convenience sampling. Consecutively diagnosed HIV-infected adults (n = 654) were included in the implementation study. Sensitivity was 82% and 20% when the LFA was read 10 minutes after direct application to finger-prick blood in the validation and implementation studies, respectively. Using a pipette to transfer blood and reading after 20 minutes improved sensitivity to 100%, while retaining 100% specificity, in both studies. CONCLUSIONS Although the IMMY CrAg LFA performs well when applied directly to finger-prick blood for diagnosing cryptococcal meningitis, this technique may not provide adequate volume to detect low concentrations of CrAg when screening asymptomatic patients. Using a pipette to transfer larger volumes of blood to diluent before CrAg LFA testing and reading results after 20 minutes is a more reliable point-of-care method.
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Jarvis JN, Harrison TS. Understanding Causal Pathways in Cryptococcal Meningitis Immune Reconstitution Inflammatory Syndrome. J Infect Dis 2018; 219:344-346. [DOI: 10.1093/infdis/jiy448] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2018] [Accepted: 07/12/2018] [Indexed: 11/13/2022] Open
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Dambuza IM, Drake T, Chapuis A, Zhou X, Correia J, Taylor-Smith L, LeGrave N, Rasmussen T, Fisher MC, Bicanic T, Harrison TS, Jaspars M, May RC, Brown GD, Yuecel R, MacCallum DM, Ballou ER. The Cryptococcus neoformans Titan cell is an inducible and regulated morphotype underlying pathogenesis. PLoS Pathog 2018; 14:e1006978. [PMID: 29775474 PMCID: PMC5959070 DOI: 10.1371/journal.ppat.1006978] [Citation(s) in RCA: 97] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 03/16/2018] [Indexed: 02/06/2023] Open
Abstract
Fungal cells change shape in response to environmental stimuli, and these morphogenic transitions drive pathogenesis and niche adaptation. For example, dimorphic fungi switch between yeast and hyphae in response to changing temperature. The basidiomycete Cryptococcus neoformans undergoes an unusual morphogenetic transition in the host lung from haploid yeast to large, highly polyploid cells termed Titan cells. Titan cells influence fungal interaction with host cells, including through increased drug resistance, altered cell size, and altered Pathogen Associated Molecular Pattern exposure. Despite the important role these cells play in pathogenesis, understanding the environmental stimuli that drive the morphological transition, and the molecular mechanisms underlying their unique biology, has been hampered by the lack of a reproducible in vitro induction system. Here we demonstrate reproducible in vitro Titan cell induction in response to environmental stimuli consistent with the host lung. In vitro Titan cells exhibit all the properties of in vivo generated Titan cells, the current gold standard, including altered capsule, cell wall, size, high mother cell ploidy, and aneuploid progeny. We identify the bacterial peptidoglycan subunit Muramyl Dipeptide as a serum compound associated with shift in cell size and ploidy, and demonstrate the capacity of bronchial lavage fluid and bacterial co-culture to induce Titanisation. Additionally, we demonstrate the capacity of our assay to identify established (cAMP/PKA) and previously undescribed (USV101) regulators of Titanisation in vitro. Finally, we investigate the Titanisation capacity of clinical isolates and their impact on disease outcome. Together, these findings provide new insight into the environmental stimuli and molecular mechanisms underlying the yeast-to-Titan transition and establish an essential in vitro model for the future characterization of this important morphotype.
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Molloy SF, Kanyama C, Heyderman RS, Loyse A, Kouanfack C, Chanda D, Mfinanga S, Temfack E, Lakhi S, Lesikari S, Chan AK, Stone N, Kalata N, Karunaharan N, Gaskell K, Peirse M, Ellis J, Chawinga C, Lontsi S, Ndong JG, Bright P, Lupiya D, Chen T, Bradley J, Adams J, van der Horst C, van Oosterhout JJ, Sini V, Mapoure YN, Mwaba P, Bicanic T, Lalloo DG, Wang D, Hosseinipour MC, Lortholary O, Jaffar S, Harrison TS. Antifungal Combinations for Treatment of Cryptococcal Meningitis in Africa. N Engl J Med 2018. [PMID: 29539274 DOI: 10.1056/nejmoa1710922] [Citation(s) in RCA: 259] [Impact Index Per Article: 43.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
BACKGROUND Cryptococcal meningitis accounts for more than 100,000 human immunodeficiency virus (HIV)-related deaths per year. We tested two treatment strategies that could be more sustainable in Africa than the standard of 2 weeks of amphotericin B plus flucytosine and more effective than the widely used fluconazole monotherapy. METHODS We randomly assigned HIV-infected adults with cryptococcal meningitis to receive an oral regimen (fluconazole [1200 mg per day] plus flucytosine [100 mg per kilogram of body weight per day] for 2 weeks), 1 week of amphotericin B (1 mg per kilogram per day), or 2 weeks of amphotericin B (1 mg per kilogram per day). Each patient assigned to receive amphotericin B was also randomly assigned to receive fluconazole or flucytosine as a partner drug. After induction treatment, all the patients received fluconazole consolidation therapy and were followed to 10 weeks. RESULTS A total of 721 patients underwent randomization. Mortality in the oral-regimen, 1-week amphotericin B, and 2-week amphotericin B groups was 18.2% (41 of 225), 21.9% (49 of 224), and 21.4% (49 of 229), respectively, at 2 weeks and was 35.1% (79 of 225), 36.2% (81 of 224), and 39.7% (91 of 229), respectively, at 10 weeks. The upper limit of the one-sided 97.5% confidence interval for the difference in 2-week mortality was 4.2 percentage points for the oral-regimen group versus the 2-week amphotericin B groups and 8.1 percentage points for the 1-week amphotericin B groups versus the 2-week amphotericin B groups, both of which were below the predefined 10-percentage-point noninferiority margin. As a partner drug with amphotericin B, flucytosine was superior to fluconazole (71 deaths [31.1%] vs. 101 deaths [45.0%]; hazard ratio for death at 10 weeks, 0.62; 95% confidence interval [CI], 0.45 to 0.84; P=0.002). One week of amphotericin B plus flucytosine was associated with the lowest 10-week mortality (24.2%; 95% CI, 16.2 to 32.1). Side effects, such as severe anemia, were more frequent with 2 weeks than with 1 week of amphotericin B or with the oral regimen. CONCLUSIONS One week of amphotericin B plus flucytosine and 2 weeks of fluconazole plus flucytosine were effective as induction therapy for cryptococcal meningitis in resource-limited settings. (ACTA Current Controlled Trials number, ISRCTN45035509 .).
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Jindani A, Borgulya G, de Patiño IW, Gonzales T, de Fernandes RA, Shrestha B, Atwine D, Bonnet M, Burgos M, Dubash F, Patel N, Checkley AM, Harrison TS, Mitchison D. A randomised Phase II trial to evaluate the toxicity of high-dose rifampicin to treat pulmonary tuberculosis. Int J Tuberc Lung Dis 2018; 20:832-8. [PMID: 27155189 DOI: 10.5588/ijtld.15.0577] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
SETTING Randomised Phase IIB clinical trial. OBJECTIVES To assess whether increasing the dose of rifampicin (RMP) from 10 mg/kg to 15 or 20 mg/kg results in an increase in grade 3 or 4 hepatic adverse events and/or serious adverse events (SAE). METHODS Three hundred human immunodeficiency virus negative patients with newly diagnosed microscopy-positive pulmonary tuberculosis (TB) were randomly assigned to one of three regimens: 1) the control regimen (R10), comprising daily ethambutol (EMB), isoniazid (INH), RMP and pyrazinamide for 8 weeks, followed by INH and RMP daily for 18 weeks; 2) Study Regimen 1 (R15), as above, with the RMP dose increased to 15 mg/kg body weight daily for the first 16 weeks; and 3) Study Regimen 2 (R20), as above, with RMP increased to 20 mg/kg. Serum alanine transferase (ALT) levels were measured at regular intervals. RESULTS There were seven grade 3 increases in ALT levels, 1/100 (1%) among R10 arm patients, 2/100 (2%) in the R15 arm and 4/100 (4%) in the R20 arm (trend test P = 0.15). One (R15) patient developed jaundice, requiring treatment modification. There were no grade 4 ALT increases. There was a non-significant increase in culture negativity at 8 weeks with increasing RMP dosage: 75% (69/92) in R10, 82.5% (66/80) in R15 and 83.1% (76/91) R20 patients (P = 0.16). CONCLUSIONS No significant increase in adverse events occurred when the RMP dose was increased from 10 mg/kg to 15 mg/kg or 20 mg/kg.
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Wake RM, Britz E, Sriruttan C, Rukasha I, Omar T, Spencer DC, Nel JS, Mashamaite S, Adelekan A, Chiller TM, Jarvis JN, Harrison TS, Govender NP. High Cryptococcal Antigen Titers in Blood Are Predictive of Subclinical Cryptococcal Meningitis Among Human Immunodeficiency Virus-Infected Patients. Clin Infect Dis 2018; 66:686-692. [PMID: 29028998 PMCID: PMC6220350 DOI: 10.1093/cid/cix872] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 10/03/2017] [Indexed: 01/30/2023] Open
Abstract
Background High mortality rates among asymptomatic cryptococcal antigen (CrAg)-positive patients identified through CrAg screening, despite preemptive fluconazole treatment, may be due to undiagnosed cryptococcal meningitis. Methods Symptoms were reviewed in CrAg-positive patients identified by screening 19233 individuals with human immunodeficiency virus infection and CD4 cell counts <100/µL at 17 clinics and 3 hospitals in Johannesburg from September 2012 until September 2015, and at 2 hospitals until June 2016. Cerebrospinal fluid samples from 90 of 254 asymptomatic patients (35%) and 78 of 173 (45%) with headache only were analyzed for cryptococcal meningitis, considered present if Cryptococcus was identified by means of India ink microscopy, culture, or CrAg test. CrAg titers were determined with stored blood samples from 62 of these patients. The associations between blood CrAg titer, concurrent cryptococcal meningitis, and mortality rate were assessed. Results Cryptococcal meningitis was confirmed in 34% (95% confidence interval, 25%-43%; 31 of 90) of asymptomatic CrAg-positive patients and 90% (81%-96%; 70 of 78) with headache only. Blood CrAg titer was significantly associated with concurrent cryptococcal meningitis in asymptomatic patients (P < .001) and patients with headache only (P = .003). The optimal titer for predicting cryptococcal meningitis was >160 (sensitivity, 88.2%; specificity, 82.1%); the odds ratio for concurrent cryptococcal meningitis was 34.5 (95% confidence interval, 8.3-143.1; P < .001). Conclusions About a third of asymptomatic CrAg-positive patients have concurrent cryptococcal meningitis. More effective clinical assessment strategies and antifungal regimens are required for CrAg-positive patients, including investigation for cryptococcal meningitis irrespective of symptoms. Where it is not possible to perform lumbar punctures in all CrAg-positive patients, blood CrAg titers should be used to target those most at risk of cryptococcal meningitis.
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Bright PD, Lupiya D, van Oosterhout JJ, Chen A, Harrison TS, Chan AK. The treatment of a pregnant HIV positive patient with cryptococcal meningitis in Malawi. Case report and review of treatment options. Med Mycol Case Rep 2017; 19:9-12. [PMID: 30148053 PMCID: PMC6105915 DOI: 10.1016/j.mmcr.2017.10.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 10/27/2017] [Indexed: 01/20/2023] Open
Abstract
This case reports cryptococcal meningitis in an HIV positive woman on antiretroviral therapy, presenting with left middle cerebral artery stroke at 30 weeks gestation. The patient had well-controlled HIV (CD4 count over 200 cells/mL). The immunosuppressive effects of the pregnancy likely contributed to the development of cryptococcal disease. The patient was successfully treated with two weeks of amphotericin B followed by fluconazole, delivered a healthy baby, but remained with a permanent severe neurological deficit.
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Arnold A, Cooke GS, Kon OM, Dedicoat M, Lipman M, Loyse A, Chis Ster I, Harrison TS. Adverse Effects and Choice between the Injectable Agents Amikacin and Capreomycin in Multidrug-Resistant Tuberculosis. Antimicrob Agents Chemother 2017; 61:e02586-16. [PMID: 28696239 PMCID: PMC5571306 DOI: 10.1128/aac.02586-16] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 06/09/2017] [Indexed: 11/20/2022] Open
Abstract
The prolonged use of injectable agents in a regimen for the treatment of multidrug-resistant tuberculosis (MDR-TB) is recommended by the World Health Organization, despite its association with ototoxicity and nephrotoxicity. We undertook this study to look at the relative adverse effects of capreomycin and amikacin. We reviewed the case notes of 100 consecutive patients treated at four MDR-TB treatment centers in the United Kingdom. The median total duration of treatment with an injectable agent was 178 days (interquartile range [IQR], 109 to 192 days; n = 73) for those with MDR-TB, 179 days (IQR, 104 to 192 days; n = 12) for those with MDR-TB plus fluoroquinolone resistance, and 558 days (IQR, 324 to 735 days; n = 8) for those with extensively drug-resistant tuberculosis (XDR-TB). Injectable use was longer for those started with capreomycin (183 days; IQR, 123 to 197 days) than those started with amikacin (119 days; IQR, 83 to 177 days) (P = 0.002). Excluding patients with XDR-TB, 51 of 85 (60%) patients were treated with an injectable for over 6 months and 12 of 85 (14%) were treated with an injectable for over 8 months. Forty percent of all patients discontinued the injectable due to hearing loss. Fifty-five percent of patients experienced ototoxicity, which was 5 times (hazard ratio [HR], 5.2; 95% confidence interval [CI], 1.2 to 22.6; P = 0.03) more likely to occur in those started on amikacin than in those treated with capreomycin only. Amikacin was associated with less hypokalemia than capreomycin (odds ratio, 0.28; 95% CI, 0.11 to 0.72), with 5 of 37 (14%) patients stopping capreomycin due to recurrent electrolyte loss. There was no difference in the number of patients experiencing a rise in the creatinine level of >1.5 times the baseline level. Hearing loss is frequent in this cohort, though its incidence is significantly lower in those starting capreomycin, which should be given greater consideration as a first-line agent.
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Limper AH, Adenis A, Le T, Harrison TS. Fungal infections in HIV/AIDS. THE LANCET. INFECTIOUS DISEASES 2017; 17:e334-e343. [PMID: 28774701 DOI: 10.1016/s1473-3099(17)30303-1] [Citation(s) in RCA: 264] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 06/29/2016] [Revised: 03/13/2017] [Accepted: 03/14/2017] [Indexed: 01/25/2023]
Abstract
Fungi are major contributors to the opportunistic infections that affect patients with HIV/AIDS. Systemic infections are mainly with Pneumocystis jirovecii (pneumocystosis), Cryptococcus neoformans (cryptococcosis), Histoplasma capsulatum (histoplasmosis), and Talaromyces (Penicillium) marneffei (talaromycosis). The incidence of systemic fungal infections has decreased in people with HIV in high-income countries because of the widespread availability of antiretroviral drugs and early testing for HIV. However, in many areas with high HIV prevalence, patients present to care with advanced HIV infection and with a low CD4 cell count or re-present with persistent low CD4 cell counts because of poor adherence, resistance to antiretroviral drugs, or both. Affordable, rapid point-of-care diagnostic tests (as have been developed for cryptococcosis) are urgently needed for pneumocystosis, talaromycosis, and histoplasmosis. Additionally, antifungal drugs, including amphotericin B, liposomal amphotericin B, and flucytosine, need to be much more widely available. Such measures, together with continued international efforts in education and training in the management of fungal disease, have the potential to improve patient outcomes substantially.
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Molloy SF, Chiller T, Greene GS, Burry J, Govender NP, Kanyama C, Mfinanga S, Lesikari S, Mapoure YN, Kouanfack C, Sini V, Temfack E, Boulware DR, Dromer F, Denning DW, Day J, Stone NRH, Bicanic T, Jarvis JN, Lortholary O, Harrison TS, Jaffar S, Loyse A. Cryptococcal meningitis: A neglected NTD? PLoS Negl Trop Dis 2017; 11:e0005575. [PMID: 28662028 PMCID: PMC5490932 DOI: 10.1371/journal.pntd.0005575] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
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Vanhove M, Beale MA, Rhodes J, Chanda D, Lakhi S, Kwenda G, Molloy S, Karunaharan N, Stone N, Harrison TS, Bicanic T, Fisher MC. Genomic epidemiology of Cryptococcus yeasts identifies adaptation to environmental niches underpinning infection across an African HIV/AIDS cohort. Mol Ecol 2017; 26:1991-2005. [PMID: 27862555 PMCID: PMC5412878 DOI: 10.1111/mec.13891] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 10/15/2016] [Accepted: 10/17/2016] [Indexed: 12/21/2022]
Abstract
Emerging infections caused by fungi have become a widely recognized global phenomenon and are causing an increasing burden of disease. Genomic techniques are providing new insights into the structure of fungal populations, revealing hitherto undescribed fine-scale adaptations to environments and hosts that govern their emergence as infections. Cryptococcal meningitis is a neglected tropical disease that is responsible for a large proportion of AIDS-related deaths across Africa; however, the ecological determinants that underlie a patient's risk of infection remain largely unexplored. Here, we use genome sequencing and ecological genomics to decipher the evolutionary ecology of the aetiological agents of cryptococcal meningitis, Cryptococcus neoformans and Cryptococcus gattii, across the central African country of Zambia. We show that the occurrence of these two pathogens is differentially associated with biotic (macroecological) and abiotic (physical) factors across two key African ecoregions, Central Miombo woodlands and Zambezi Mopane woodlands. We show that speciation of Cryptococcus has resulted in adaptation to occupy different ecological niches, with C. neoformans found to occupy Zambezi Mopane woodlands and C. gattii primarily recovered from Central Miombo woodlands. Genome sequencing shows that C. neoformans causes 95% of human infections in this region, of which over three-quarters belonged to the globalized lineage VNI. We show that VNI infections are largely associated with urbanized populations in Zambia. Conversely, the majority of C. neoformans isolates recovered in the environment belong to the genetically diverse African-endemic lineage VNB, and we show hitherto unmapped levels of genomic diversity within this lineage. Our results reveal the complex evolutionary ecology that underpins the reservoirs of infection for this, and likely other, deadly pathogenic fungi.
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MESH Headings
- Adaptation, Physiological/genetics
- Cryptococcus gattii/genetics
- Cryptococcus neoformans/genetics
- DNA Barcoding, Taxonomic
- DNA, Fungal/genetics
- DNA, Ribosomal Spacer/genetics
- Forests
- Genetics, Population
- Genome, Fungal
- Genomics
- Humans
- Meningitis, Cryptococcal/epidemiology
- Meningitis, Cryptococcal/microbiology
- Models, Biological
- Phylogeny
- Plant Bark/microbiology
- Polymorphism, Single Nucleotide
- Soil Microbiology
- Trees/microbiology
- Zambia
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