Improvements in the immunologic tests performed on cerebrospinal fluid have increased the sensitivity and reduced the turnaround time for diagnosis of central nervous system histoplasmosis over prior antigen and antibody detection methods and culture.

The triazole antifungal itraconazole may be cost prohibitive in brand name form; therefore, compounded and generic products are often used as alternatives. Itraconazole blood concentrations have not been studied in clinical patients receiving these formulations. Itraconazole bioassay was performed on serum/plasma from 95 dogs and 20 cats receiving itraconazole (compounded from bulk powder, generic pelletized, or brand name) for systemic mycosis treatment. Mean itraconazole concentration was lower in the compounded group (n = 42) as compared with the generic (n = 40) or brand name (n = 33) groups (0.5 µg/mL versus 8.3 µg/mL and 6.5 µg/mL, respectively; P < .001). No statistical difference was observed between itraconazole concentrations in the generic and brand name groups. Forty animals (95.2%) in the compounded group had subtherapeutic (<1.0 µg/mL) values. All cats in this group (n = 10) had undetectable itraconazole concentrations. Some animals in the generic and brand name groups had subtherapeutic values (12.5 and 12.1%, respectively) or potentially toxic values (>10 µg/mL; 37.5 and 24%, respectively). Compounded itraconazole should be avoided, but generic itraconazole appears to serve as a reasonable alternative to brand name itraconazole. Therapeutic drug monitoring may be beneficial in all cases.

The diagnosis of central nervous system (CNS) histoplasmosis is often difficult. Although cerebrospinal fluid (CSF) (1,3)-β-d-glucan (BDG) is available as a biological marker for the diagnosis of fungal meningitis, there are limited data on its use for the diagnosis of meningitis. We evaluated CSF BDG detection, using the Fungitell assay, in patients with CNS histoplasmosis and controls. A total of 47 cases and 153 controls were identified. The control group included 13 patients with a CNS fungal infection other than histoplasmosis. Forty-nine percent of patients with CNS histoplasmosis and 43.8% of controls were immunocompromised. The median CSF BDG level was 85 pg/ml for cases, compared to<31 pg/ml for all controls ( < 0.05) and 82 pg/ml for controls with other causes of fungal meningitis ( = 0.27). The sensitivity for detection of BDG in CSF was 53.2%, whereas the specificity was 86.9% versus all controls and 46% versus other CNS fungal infections. CSF BDG levels of ≥80 pg/ml are neither sensitive nor specific to support a diagnosis of meningitis.

The postsynaptic density (PSD) is a protein-rich network important for the localization of postsynaptic glutamate receptors (GluRs) and for signaling downstream of these receptors. Although hundreds of PSD proteins have been identified, many are functionally uncharacterized. We conducted a reverse genetic screen for mutations that affected GluR localization using Drosophila genes that encode homologs of mammalian PSD proteins. 42.8% of the mutants analyzed exhibited a significant change in GluR localization at the third instar larval neuromuscular junction (NMJ), a model synapse that expresses homologs of AMPA receptors. We identified the E3 ubiquitin ligase, Mib1, which promotes Notch signaling, as a regulator of synaptic GluR localization. Mib1 positively regulates the localization of the GluR subunits GluRIIA, GluRIIB, and GluRIIC. Mutations in mib1 and ubiquitous expression of Mib1 that lacks its ubiquitin ligase activity result in the loss of synaptic GluRIIA-containing receptors. In contrast, overexpression of Mib1 in all tissues increases postsynaptic levels of GluRIIA. Cellular levels of Mib1 are also important for the structure of the presynaptic motor neuron. While deficient Mib1 signaling leads to overgrowth of the NMJ, ubiquitous overexpression of Mib1 results in a reduction in the number of presynaptic motor neuron boutons and branches. These synaptic changes may be secondary to attenuated glutamate release from the presynaptic motor neuron in mib1 mutants as mib1 mutants exhibit significant reductions in the vesicle-associated protein cysteine string protein and in the frequency of spontaneous neurotransmission.

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