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We utilized polymerase chain reaction (PCR) to demonstrate that Angiostrongylus cantonensis was responsible for 67.3% of 55 cases of eosinophilic meningitis from a cohort of 1,690 adult patients with CNS infection at a tertiary hospital in southern Vietnam. Longer duration of illness, depressed consciousness, and peripheral blood eosinophilia were associated with PCR positivity.

Molecular genetic approaches typically detect recombination in microbes regardless of assumed asexuality. However, genetic data have shown the AIDS-associated pathogen Penicillium marneffei to have extensive spatial genetic structure at local and regional scales, and although there has been some genetic evidence that a sexual cycle is possible, this haploid fungus is thought to be genetically, as well as morphologically, asexual in nature because of its highly clonal population structure. Here we use comparative genomics, experimental mixed-genotype infections, and population genetic data to elucidate the role of recombination in natural populations of P. marneffei. Genome wide comparisons reveal that all the genes required for meiosis are present in P. marneffei, mating type genes are arranged in a similar manner to that found in other heterothallic fungi, and there is evidence of a putatively meiosis-specific mutational process. Experiments suggest that recombination between isolates of compatible mating types may occur during mammal infection. Population genetic data from 34 isolates from bamboo rats in India, Thailand and Vietnam, and 273 isolates from humans in China, India, Thailand, and Vietnam show that recombination is most likely to occur across spatially and genetically limited distances in natural populations resulting in highly clonal population structure yet sexually reproducing populations. Predicted distributions of three different spatial genetic clusters within P. marneffei overlap with three different bamboo rat host distributions suggesting that recombination within hosts may act to maintain population barriers within P. marneffei., Author Summary Fungal pathogen populations show patterns ranging from globally recombining to endemic and clonal. Among the most genetically and spatially restricted fungi is the highly clonal pathogen Penicillium marneffei, an endemic AIDS-associated pathogen in Southeast Asia. Previous studies have shown that P. marneffei has a pattern of extreme clonality despite the ability to disperse across wide distances and the presence of mating type genes that are required for sexual recombination. In this study we used genetic markers, comparative genomics, experimental data, and spatial models to determine the influence of sex on P. marneffei populations, and we found that although there was substantial evidence of sexual recombination, most of the recombination in natural populations was limited to sexual neighborhoods, amongst genetically similar and spatially close individuals. Based on the results of experiments and spatial models we found support for sex occurring in bamboo rats that are known to harbor P. marneffei and the pathogens sexual neighborhoods. Our study suggests that the high levels of effective clonality and endemicity found in P. marneffei may have more to do with specific host interactions than with an innate inability to generate population genetic diversity through sexual recombination.

Cryptococcal disease most commonly occurs in patients with an underlying immune deficit, most commonly HIV infection, and is due to Cryptococcus neoformans var. grubii . Occasionally disease due to this variety occurs in apparently immunocompetent patients. The relationship between strains infecting immunosuppressed and immunocompetent patients is not clear. Amplified fragment length polymorphism (AFLP) analysis was used to characterize the relationship between strains infecting HIV-infected and uninfected patients. Isolates from 51 HIV-uninfected patients and 100 HIV-infected patients with cryptococcal meningitis were compared. C. neoformans var. grubii VNI was responsible for infections in 73% of HIV-uninfected and 100% of HIV-infected patients. AFLP analysis defined two distinct clusters, VNIγ and VNIδ. The majority (84%) of isolates from HIV-uninfected patients were VNIγ, compared with only 38% of isolates from HIV-infected patients (odds ratio, 8.30; 95% confidence interval [CI], 3.04 to 26.6; P < 0.0001). In HIV-uninfected patients, underlying disease was less frequent in those with VNIγ infections. Two clusters of C. neoformans var. grubii VN1 are responsible for the majority of cases of cryptococcal meningitis in Vietnam. The distribution of these clusters differs according to the immune status of the host.

Penicillium marneffei is an important human immunodeficiency virus-associated opportunistic infection endemic in Southeast Asia. Central nervous system infection has not been described. We report the first case series of 21 human immunodeficiency virus-infected patients who presented with a syndrome consistent with acute central nervous system infection and who had Penicillium marneffei isolated from cerebrospinal fluid.

PURPOSE OF REVIEW: Since the start of the HIV pandemic, systemic infection with Penicillium marneffei has developed from a very rare diagnosis to the third most common opportunistic infection in HIV co-infected patients in South East Asia. HIV patients who have travelled to or lived in Asia may present with this infection in nonendemic countries, and it has therefore become important for all those working in the field of HIV to recognize, understand and treat this emerging disease. RECENT FINDINGS: The clinical features, diagnosis and treatment of this infection are reviewed. Recent data exploring antigen-based serodiagnostics, the role of newer antifungals such as voriconazole, and the possibility of discontinuation of secondary prophylaxis after immune restoration from highly active antiretrovirals are discussed. SUMMARY: Large series from endemic areas and case reports from nonendemic regions have been published and provide insights into clinical features and presentation. Novel diagnostics are evolving, with galactomannan and other assays looking promising. Present therapy is largely based on noncontrolled studies, and further research into optimal therapy and the potential to discontinue secondary itraconazole prophylaxis is required.

A B S T R AC T BACKGROUND Combination antifungal therapy (am pho ter i cin B deoxycholate and flu cy to sine) is the recommended treatment for cryptococcal meningitis but has not been shown to reduce mortality, as compared with am pho ter i cin B alone. We performed a randomized, controlled trial to determine whether combining flu cy to sine or high-dose flu con a zole with high-dose am pho ter i cin B improved survival at 14 and 70 days. METHODS We conducted a randomized, three-group, open-label trial of induction therapy for cryptococcal meningitis in patients with human immunodeficiency virus infection. All patients received am pho ter i cin B at a dose of 1 mg per kilogram of body weight per day; patients in group 1 were treated for 4 weeks, and those in groups 2 and 3 for 2 weeks. Patients in group 2 concurrently received flu cy to sine at a dose of 100 mg per kilogram per day for 2 weeks, and those in group 3 concurrently received flu con a zole at a dose of 400 mg twice daily for 2 weeks. RESULTS A total of 299 patients were enrolled. Fewer deaths occurred by days 14 and 70 among patients receiving am pho ter i cin B and flu cy to sine than among those receiving ampho ter i cin B alone (15 vs. 25 deaths by day 14; hazard ratio, 0.57; 95% confidence interval [CI], 0.30 to 1.08; unadjusted P = 0.08; and 30 vs. 44 deaths by day 70; hazard ratio, 0.61; 95% CI, 0.39 to 0.97; unadjusted P = 0.04). Combination therapy with flu cona zole had no significant effect on survival, as compared with monotherapy (hazard ratio for death by 14 days, 0.78; 95% CI, 0.44 to 1.41; P = 0.42; hazard ratio for death by 70 days, 0.71; 95% CI, 0.45 to 1.11; P = 0.13). Am pho ter i cin B plus flu cy to sine was associated with significantly increased rates of yeast clearance from cerebrospinal fluid (−0.42 log 10 colony-forming units [CFU] per milliliter per day vs. −0.31 and −0.32 log 10 CFU per milliliter per day in groups 1 and 3, respectively; P

AIDSand#x2010;associated Cryptococcus neoformans and Penicillium marneffei coinfection has not been adequately studied and poses unique therapeutic challenges in resourceand#x2010;limited settings. Itraconazole poorly penetrates the central nervous system, whereas fluconazole has poor activity against P. marneffei. We prospectively report management of 1 patient and retrospectively review 7 coinfection cases from Vietnam.