Treatment of acute cryptococcal meningitis in HIV infected adults, with an emphasis on resource-limited settings

BACKGROUND: Despite the advent and increasingly wide availability of antiretroviral therapy, cryptococcal meningitis (CM) remains a significant cause of mortality and morbidity amongst individuals with HIV infection in resource-limited settings. The ideal management of CM remains unclear. The aim of this review is to assess the evidence for deciding on which antifungal regimen to use as well as other modalities of management to utilise especially resource poor settings in order to achieve the best possible outcome and enable an individual with CM to survive their acute illness and benefit from antiretroviral therapy. OBJECTIVES: To determine the most effective initial and consolidation treatment strategy for CM in HIV infected adults. SEARCH STRATEGY: The Cochrane HIV/AIDS group search strategy was used. Key words in the search included, meningitis, cryptococcus neoformans, treatment, trial, human immunodeficiency virus, acquired immunodeficiency syndrome, antifungal agents, amphotericin, flucytosine, fluconazole, azole, lumbar puncture, cerebrospinal fluid (CSF) pressure and acetazolamide. SELECTION CRITERIA: Randomised of HIV-infected adults with a first episode of CM diagnosed on CSF examination, by India ink staining, CSF culture or cryptococcal antigen testing. DATA COLLECTION AND ANALYSIS: Data were extracted using standardised forms and analysed using Rev Man 4.2.7 software. MAIN RESULTS: Six studies are included in the review. Five of the studies compared antifungal treatments and one study addressed lowering intracranial pressure. This study was stopped early due to excess adverse effects. The results of the other five studies as summarised as follows.Mayanja-Kizza 1998 compared fluconazole to fluconazole with 5 flucytosine. The dose of fluconazole used 200mg initially is lower than the recommended initial dose of 400mg. No survival advantage was found with the use of 5 flucytosine in addition to fluconazole.Two studies Brouwer 2004 and van der Horst 1997 compared Amphotericin (AmB) to AmB with 5 flucytosine. Both drugs were given at currently recommended doses for 2 weeks. No survival difference was found at 14 days or at 10 weeks (only recorded in Brouwer 2004). There were significantly more patients with sterile CSF cultures at 14 days in the group that received AmB with flucytosine.Brouwer 2004 compared AmB given alone to AmB given with flucytosine and fluconazole alone or in combination. This was a small study and no differences in mortality were noted between the groups.Bicanic 2008 compared high to standard dose AmB both with flucytosine. There was no difference in mortality between the two groups or adverse events.Leenders 1997 compared standard AmB to liposomal AmB. There was no difference in death rates between the two groups. But there were significantly fewer side effects in the group treated with liposomal AmB. AUTHORS' CONCLUSIONS: The main aim of this review was to determine the best treatment for cryptococcal meningitis in resource-limited settings. In these settings usually only AmB and fluconazole are available. No studies suitable for inclusion in the review were found that compared these two drugs. Therefore we are unable to recommend either treatment as superior to the other. The recommended treatment for CM is a combination of AmB and flucytosine. The optimal dosing of AmB remains unclear. Liposomal AmB is associated with less adverse events than AmB and may be useful in selected patients where resources allow.Future research into the management of cryptococcal meningitis in resource-limited settings should focus on the most effective use of medications that are available in these settings.Flucytosine in combination with AmB leads to faster and increased sterilisation of CSF compared to using AmB alone. As Flucytosine is often not available in developing countries, policy makers and national departments of heath should consider procuring this drug for HIV treatment programmes.Publisher PDFPeer reviewe

Renal impairment in a rural African antiretroviral programme

Background: There is little knowledge regarding the prevalence and nature of renal impairment in African populations initiating antiretroviral treatment, nor evidence to inform the most cost effective methods of screening for renal impairment. With the increasing availability of the potentially nephrotixic drug, tenofovir, such information is important for the planning of antiretroviral programmes Methods: (i) Retrospective review of the prevalence and risk factors for impaired renal function in 2189 individuals initiating antiretroviral treatment in a rural African setting between 2004 and 2007 (ii) A prospective study of 149 consecutive patients initiating antiretrovirals to assess the utility of urine analysis for the detection of impaired renal function. Severe renal and moderately impaired renal function were defined as an estimated GFR of ≤ 30 mls/min/1.73 m2 and 30–60 mls/min/1.73 m2 respectively. Logistic regression was used to determine odds ratio (OR) of significantly impaired renal function (combining severe and moderate impairment). Co-variates for analysis were age, sex and CD4 count at initiation. Results: (i) There was a low prevalence of severe renal impairment (29/2189, 1.3% 95% C.I. 0.8–1.8) whereas moderate renal impairment was more frequent (287/2189, 13.1% 95% C.I. 11.6–14.5) with many patients having advanced immunosuppression at treatment initiation (median CD4 120 cells/μl). In multivariable logistic regression age over 40 (aOR 4.65, 95% C.I. 3.54–6.1), male gender (aOR 1.89, 95% C.I. 1.39–2.56) and CD4<100 cells/ul (aOR 1.4, 95% C.I. 1.07–1.82) were associated with risk of significant renal impairment (ii) In 149 consecutive patients, urine analysis had poor sensitivity and specificity for detecting impaired renal function. Conclusion: In this rural African setting, significant renal impairment is uncommon in patients initiating antiretrovirals. Urine analysis alone may be inadequate for identification of those with impaired renal function where resources for biochemistry are limited

Tuberculosis incidence correlates with sunshine : an ecological 28-year time series study

Birmingham is the largest UK city after London, and central Birmingham has an annual tuberculosis incidence of 80 per 100,000. We examined seasonality and sunlight as drivers of tuberculosis incidence. Hours of sunshine are seasonal, sunshine exposure is necessary for the production of vitamin D by the body and vitamin D plays a role in the host response to tuberculosis. Methods: We performed an ecological study that examined tuberculosis incidence in Birmingham from Dec 1981 to Nov 2009, using publicly-available data from statutory tuberculosis notifications, and related this to the seasons and hours of sunshine (UK Meteorological Office data) using unmeasured component models. Results: There were 9,739 tuberculosis cases over the study period. There was strong evidence for seasonality, with notifications being 24.1% higher in summer than winter (p<0.001). Winter dips in sunshine correlated with peaks in tuberculosis incidence six months later (4.7% increase in incidence for each 100 hours decrease in sunshine, p<0.001). Discussion and Conclusion: A potential mechanism for these associations includes decreased vitamin D levels with consequent impaired host defence arising from reduced sunshine exposure in winter. This is the longest time series of any published study and our use of statutory notifications means this data is essentially complete. We cannot, however, exclude the possibility that another factor closely correlated with the seasons, other than sunshine, is responsible. Furthermore, exposure to sunlight depends not only on total hours of sunshine but also on multiple individual factors. Our results should therefore be considered hypothesis-generating. Confirmation of a potential causal relationship between winter vitamin D deficiency and summer peaks in tuberculosis incidence would require a randomized-controlled trial of the effect of vitamin D supplementation on future tuberculosis incidence

IgG glycosylation associates with risk of progression from latent to active tuberculosis

Glycosylation motifs shape antibody structure, stability and antigen affinity and play an important role in antibody localization and function. Serum IgG glycosylation profiles are significantly altered in infectious diseases, including tuberculosis (TB), but have not been studied in the context of progression from latent to active TB. We performed a longitudinal study of paired bulk IgG glycosylation and transcriptomic profiling in blood from individuals with active TB (ATB) or latent TB infection (LTBI) before and after treatment. We identified that a combination of two IgG1 glycosylation traits were sufficient to distinguish ATB from LTBI with high specificity and sensitivity, prior to, and after treatment. Importantly, these two features positively correlated with previously defined cellular and RNA signatures of ATB risk in LTBI, namely monocyte to lymphocyte ratio and the expression of interferon (IFN)-associated gene signature of progression (IFN-risk signature) in blood prior to treatment. Additional glycosylation features at higher prevalence in LTBI individuals with high expression of the IFN-risk signature prior to treatment included fucosylation on IgG1, IgG2 and IgG3. Together, our results demonstrate that bulk IgG glycosylation features could be useful in stratifying the risk of LTBI reactivation and progression to ATB