Toxicity of Amphotericin B Deoxycholate-Based Induction Therapy in Patients with HIV-Associated Cryptococcal Meningitis.

Amphotericin B deoxycholate (AmBd) is the recommended induction treatment for HIV-associated cryptococcal meningitis (CM). Its use is hampered by toxicities that include electrolyte abnormalities, nephrotoxicity, and anemia. Protocols to minimize toxicity are applied inconsistently. In a clinical trial cohort of AmBd-based CM induction treatment, a standardized protocol of preemptive hydration and electrolyte supplementation was applied. Changes in blood counts, electrolyte levels, and creatinine levels over 14 days were analyzed in relation to the AmBd dose, treatment duration (short course of 5 to 7 days or standard course of 14 days), addition of flucytosine (5FC), and outcome. In the 368 patients studied, the hemoglobin levels dropped by a mean of 1.5 g/dl (95% confidence interval [CI], 1.0 to 1.9 g/dl) following 7 days of AmBd and by a mean of 2.3 g/dl (95% CI, 1.1 to 3.6 g/dl) after 14 days. Serum creatinine levels increased by 37 μmol/liter (95% CI, 30 to 45 μmol/liter) by day 7 and by 49 μmol/liter (95% CI, 35 to 64μmol/liter) by day 14 of AmBd treatment. Overall, 33% of patients developed grade III/IV anemia, 5.6% developed grade III hypokalemia, 9.5% had creatinine levels that exceeded 220 μmol, and 6% discontinued AmBd prematurely. The addition of 5FC was associated with a slight increase in anemia but not neutropenia. Laboratory abnormalities stabilized or reversed during the second week in patients on short-course induction. Grade III/IV anemia (adjusted odds ratio [aOR], 2.2; 95% CI, 1.1 to 4.3; P = 0.028) and nephrotoxicity (aOR, 4.5; 95% CI, 1.8 to 11; P = 0.001) were risk factors for 10-week mortality. In summary, routine intravenous saline hydration and preemptive electrolyte replacement during AmBd-based induction regimens for HIV-associated CM minimized the incidence of hypokalemia and nephrotoxicity. Anemia remained a concerning adverse effect. The addition of flucytosine was not associated with increased neutropenia. Shorter AmBd courses were less toxic, with rapid reversibility

Investigating metabolic and molecular ecological evolution of opportunistic pulmonary fungal coinfections: protocol for a laboratory-based cross-sectional study

Background: Fungal-bacterial cocolonization and coinfections pose an emerging challenge among patients suspected of having pulmonary tuberculosis (PTB); however, the underlying pathogenic mechanisms and microbiome interactions are poorly understood. Understanding how environmental microbes, such as fungi and bacteria, coevolve and develop traits to evade host immune responses and resist treatment is critical to controlling opportunistic pulmonary fungal coinfections. In this project, we propose to study the coexistence of fungal and bacterial microbial communities during chronic pulmonary diseases, with a keen interest in underpinning fungal etiological evolution and the predominating interactions that may exist between fungi and bacteria. Objective: This is a protocol for a study aimed at investigating the metabolic and molecular ecological evolution of opportunistic pulmonary fungal coinfections through determining and characterizing the burden, etiological profiles, microbial communities, and interactions established between fungi and bacteria as implicated among patients with presumptive PTB. Methods: This will be a laboratory-based cross-sectional study, with a sample size of 406 participants. From each participant, 2 sputa samples (one on-spot and one early morning) will be collected. These samples will then be analyzed for both fungal and bacterial etiology using conventional metabolic and molecular (intergenic transcribed spacer and 16S ribosomal DNA–based polymerase chain reaction) approaches. We will also attempt to design a genome-scale metabolic model for pulmonary microbial communities to analyze the composition of the entire microbiome (ie, fungi and bacteria) and investigate host-microbial interactions under different patient conditions. This analysis will be based on the interplays of genes (identified by metagenomics) and inferred from amplicon data and metabolites (identified by metabolomics) by analyzing the full data set and using specific computational tools. We will also collect baseline data, including demographic and clinical history, using a patient-reported questionnaire. Altogether, this approach will contribute to a diagnostic-based observational study. The primary outcome will be the overall fungal and bacterial diagnostic profile of the study participants. Other diagnostic factors associated with the etiological profile, such as incidence and prevalence, will also be analyzed using univariate and multivariate schemes. Odds ratios with 95% CIs will be presented with a statistical significance set at P<.05. Results: The study has been approved by the Mbarara University Research Ethic Committee (MUREC1/7-07/09/20) and the Uganda National Council of Science and Technology (HS1233ES). Following careful scrutiny, the protocol was designed to enable patient enrollment, which began in March 2022 at Mbarara University Teaching Hospital. Data collection is ongoing and is expected to be completed by August 2023, and manuscripts will be submitted for publication thereafter. Conclusions: Through this protocol, we will explore the metabolic and molecular ecological evolution of opportunistic pulmonary fungal coinfections among patients with presumptive PTB. Establishing key fungal-bacterial cross-kingdom synergistic relationships is crucial for instituting fungal bacterial coinfecting etiology. Trial Registration: ISRCTN Registry ISRCTN33572982; https://tinyurl.com/caa2nw69 International Registered Report Identifier (IRRID): DERR1-10.2196/48014 JMIR Res Protoc 2023;12:e48014 doi:10.2196/4801

Short course amphotericin B with high dose fluconazole for HIV-associated cryptococcal meningitis.

OBJECTIVE: To define more rapidly effective initial antifungal regimens sustainable in resource-constrained settings. METHODS: Cohort study in SW Uganda: Thirty HIV-seropositive, antiretroviral therapy-naïve, patients with first episode cryptococcal meningitis were treated with high dose fluconazole (1200 mg/d for 2 weeks, then 800 mg/d until ART started) plus amphotericin B (AmB, 1 mg/kg/d), with routine normal saline and potassium supplementation, for the initial 5 days. Outcome measures were early fungicidal activity (EFA), determined by serial quantitative CSF cultures, safety, and mortality. RESULTS: EFA was -0.30 ± 0.11 log CFU/day calculated over the first 2 weeks of treatment, with no reduction in the rate of clearance between days 5 and 14. There was no grade IV hypokalemia or elevated creatinine, and no grade III or IV anemia or elevation of ALT. AmB or high dose fluconazole were not stopped early in any patient. Mortality was 23% at 2, and 28% at 10 weeks. CONCLUSIONS: Short course AmB was associated with rapid clearance of infection and was well-tolerated, suggesting it could be used safely in many centres currently relying on fluconazole monotherapy. Phase III trials are needed in African centres to compare short course with the standard 2-week course of AmB

Multisite Validation of Cryptococcal Antigen Lateral Flow Assay and Quantification by Laser Thermal Contrast

Cryptococcal meningitis is common in sub-Saharan Africa. Given the need for data for a rapid, point-of-care cryptococcal antigen (CRAG) lateral flow immunochromatographic assay (LFA), we assessed diagnostic performance of cerebrospinal fluid (CSF) culture, CRAG latex agglutination, India ink microscopy, and CRAG LFA for 832 HIV-infected persons with suspected meningitis during 2006–2009 (n = 299) in Uganda and during 2010–2012 (n = 533) in Uganda and South Africa. CRAG LFA had the best performance (sensitivity 99.3%, specificity 99.1%). Culture sensitivity was dependent on CSF volume (82.4% for 10 μL, 94.2% for 100 μL). CRAG latex agglutination test sensitivity (97.0%–97.8%) and specificity (85.9%–100%) varied between manufacturers. India ink microscopy was 86% sensitive. Laser thermal contrast had 92% accuracy (R = 0.91, p<0.001) in quantifying CRAG titers from 1 LFA strip to within <1.5 dilutions of actual CRAG titers. CRAG LFA is a major advance for meningitis diagnostics in resource-limited settings