Imperative role of glycosylation in human MOG-HLA interaction: molecular insights of MOG-Ab associated demyelination.

Myelin oligodendrocyte glycoprotein is a transmembrane protein found on the outer lamella of the myelin sheath. The autoimmune attack on the MOG leads to demyelination which differs from normal multiple sclerosis. MOG has three epitope regions MOG1-22, MOG35-55, and MOG92-106 in the extracellular region, and the crucial MOG35-55 epitope and Human Leukocyte Antigen (HLA) interaction is the initial step for autoantibody generation. To study the effective role of glycosylation in MOG-HLA interaction, we performed molecular dynamics simulations of the complex where HLA interacts with three MOG epitopes both in the absence and presence of glycan. The results projected that the epitope MOG1-22 is decisive for the HLA interaction in the absence of glycan and HLA interacts with the epitope MOG35-55 irrespective of glycan existence. The residues Arg9, Arg46, and Arg66 were found to interact strongly with HLA even in the presence of glycan. The glycan increased the flexibility of hMOG and enhanced the interaction of MOG with water molecules.

Utility of multiplex polymerase chain reaction (PCR) in diarrhea-An Indian perspective.

BACKGROUND: Infective diarrhea causes morbidity worldwide. Polymerase chain reaction (PCR)-based pathogen diagnostics of diarrheal stool specimens are shown to be highly sensitive and rapid as opposed to conventional diagnostics. METHODS: We analyzed the performance of FilmArray gastrointestinal (GI) panel, one such multiplex PCR test, on stool specimens in patients presenting with diarrhea to our hospital from March 2016 to September 2017 and compared the results with conventional diagnostic tests. RESULTS: A total of 106 patients were included. The panel detected at least one target in 54 out of 106 patients (50.9%) with results available on the same day. Multiple targets were detected in 26 out of 54 patients who tested positive (48.1%). Bacteria as an isolated etiology for diarrhea was present in 34 patients (62.9%), viruses (16.7%, nine patients), parasites (7.4%, four patients), and multiple pathogens in seven patients (12.9%). Enteroaggregative Escherichia coli (EAEC) was the commonest pathogen detected (in 23, 24% patients). Conventional diagnostic investigations, undertaken in 68/106 (64.1%) patients were positive in 12 (17.65%) as compared to 54/106 (50.9%) (p < 0.0001). Conventional  investigations detected a pathogen not included in the study panel in 11 of 52 patients (21.1%). CONCLUSION: FilmArray multiplex PCR panel detects a wide array of GI pathogens including viruses and co-infections at a shorter time with more sensitivity compared to conventional diagnostics. Henceforth, it may facilitate treatment decisions, isolation policy, and antimicrobial stewardship in patients with diarrhea requiring hospitalization.

Experience with ß-D-Glucan Assay in the Management of Critically ill Patients with High Risk of Invasive Candidiasis: An Observational Study.

BACKGROUND: The (1,3)-ß-D-glucan assay (BDG) is recommended for the early diagnosis of invasive candidiasis (IC). METHODS: Records of 154 critically ill adults with suspected IC, on whom BDG was done, were analyzed. Patients were divided into three groups: Group A (confirmed IC), Group B (alternative diagnosis or cause of severe sepsis), and Group C (high candidal score and positive BDG [>80 pg/mL] but without a confirmed diagnosis of IC). RESULTS: Mean BDG levels were significantly higher in Group A (n = 32) as compared to Group B (n = 60) and Group C (n = 62) (448.75 ± 88.30 vs. 144.46 ± 82.49 vs. 292.90 ± 137.0 pg/mL; P < 0.001). Discontinuation of empiric antifungal therapy based on a value <80 resulted in cost savings of 14,000 INR per day per patient. CONCLUSION: A BDG value of <80 pg/ml facilitates early discontinuation of empirical antifungal therapy, with considerable cost savings.

A Study of 24 Patients with Colistin-Resistant Gram-negative Isolates in a Tertiary Care Hospital in South India.

BACKGROUND: As the use of colistin to treat carbapenem-resistant Gram-negative infections increases, colistin resistance is being increasingly reported in Indian hospitals. MATERIALS AND METHODS: Retrospective chart review of clinical data from patients with colistin-resistant isolates (minimum inhibitory concentration >2 mcg/ml). Clinical profile, outcome, and antibiotics that were used for treatment were analyzed. RESULTS: Twenty-four colistin-resistant isolates were reported over 18 months (January 2014-June 2015). A history of previous hospitalization within 3 months was present in all the patients. An invasive device was used in 22 (91.67%) patients. Urine was the most common source of the isolate, followed by blood and respiratory samples. Klebsiella pneumoniae constituted 87.5% of all isolates. Sixteen (66.6%) were considered to have true infection, whereas eight (33.3%) were considered to represent colonization. Susceptibility of these isolates to other drugs tested was tigecycline in 75%, chloramphenicol 62.5%, amikacin 29.17%, co-trimoxazole 12.5%, and fosfomycin (sensitive in all 4 isolates tested). Antibiotics that were used for treatment were combinations among the following antimicrobials-tigecycline, chloramphenicol, fosfomycin, amikacin, ciprofloxacin, co-trimoxazole, and sulbactam. Among eight patients who were considered to have colonization, there were no deaths. Bacteremic patients had a significantly higher risk of death compared to all nonbacteremic patients (P = 0.014). CONCLUSIONS: Colistin resistance among Gram-negative bacteria, especially K. pneumoniae, is emerging in Indian hospitals. At least one-third of isolates represented colonization only rather than true infection and did not require treatment. Among patients with true infection, only 25% had a satisfactory outcome and survived to discharge. Fosfomycin, tigecycline, and chloramphenicol may be options for combination therapy.

Cladophialophora bantiana brain abscess: A report of two cases treated with voriconazole.

Cerebral phaeohyphomycosis is an infection caused by a number of dematiaceous fungi, characterised by the presence of melanised hyphae in the invaded tissue. Cladophialophora bantiana is the most common species affecting the humans, which has a predilection for causing the central nervous system infections resulting in high mortality. We hereby report a success story of two cases of brain abscess caused by C. bantiana who were treated with surgical source reduction and voriconazole therapy.