Point-of-care diagnosis of tissue fibrosis: a review of advances in vibrational spectroscopy with machine learning.

Histopathology is the gold standard for diagnosing fibrosis, but its routine use is constrained by the need for additional stains, time, personnel and resources. Vibrational spectroscopy is a novel technique that offers an alternative atraumatic approach, with short scan times, while providing metabolic and morphological data. This review evaluates vibrational spectroscopy for the assessment of fibrosis, with a focus on point-of-care capabilities. OVID Medline, Embase and Cochrane databases were systematically searched using PRISMA guidelines for search terms including vibrational spectroscopy, human tissue and fibrosis. Studies were stratified based on imaging modality and tissue type. Outcomes recorded included tissue type, machine learning technique, metrics for accuracy and author conclusions. Systematic review yielded 420 articles, of which 14 were relevant. Ten of these articles considered mid-infrared spectroscopy, three dealt with Raman spectroscopy and one with near-infrared spectroscopy. The metrics for detecting fibrosis were Pearson correlation coefficients ranging from 0.65-0.98; sensitivity from 76-100%; specificity from 90-99%; area under receiver operator curves from 0.83-0.98; and accuracy of 86-99%. Vibrational spectroscopy identified fibrosis in myeloproliferative neoplasms in bone, cirrhotic and hepatocellular carcinoma in liver, end-stage heart failure in cardiac tissue and following laser ablation for acne in skin. It also identified interstitial fibrosis as a predictor of early renal transplant rejection in renal tissue. Vibrational spectroscopic techniques can therefore accurately identify fibrosis in a range of human tissues. Emerging data show that it can be used to quantify, classify and provide data about the nature of fibrosis with a high degree of accuracy with potential scope for point-of-care use.

IgA Determines Bacterial Composition in the Gut.

Background: Classically, IgA in the gut prevents the invasion of microorganisms to systemic organs through the process of neutralization and immune exclusion. Interestingly, recent reports suggest that IgA might help in biofilm formation and promote bacterial growth inside the intestine. Methods: In this study, we used flow cytometry, ELISA, and chemical models of colitis to test whether the quality and quantity of IgA can select for bacterial persistence in the gut. Results: We found that members of Proteobacteria, such as γ-Proteobacteria and SFB, are preferentially coated by IgA in WT mice. In the partial absence of either T-dependent or -independent IgA responses, there are no significant differences in the frequency of bacteria coated with IgA in mice. However, Rag-/- mice that lack all antibodies had a severe reduction in Proteobacteria and were resistant to DSS-induced colitis, suggesting that secretory IgA might be essential for differential retention of these taxa in the mouse gut. Rag-/- littermates in the F2 generation generated from (B6 × Rag-/-) F1 mice acquired the underrepresented bacteria taxa such as γ-Proteobacteria through vertical transmission of flora. They died soon after weaning, possibly due to the acquired flora. Additionally, continued exposure of Rag-/- mice to B6 flora by cohousing mice led to the acquisition of γ-Proteobacteria and mortality. Conclusions: Together, our results indicate that host survival in the complete absence of an IgA response necessitates the exclusion of specific bacterial taxa from the gut microbiome.

Acute Cerebellitis as a Rare Treatable Cause of Obstructive Hydrocephalus.

Acute cerebellitis commonly presents as acute ataxia in children. Rarely, it can result in obstructive hydrocephalus. We report a 10-year-old boy with Mycoplasma infection-associated acute cerebellitis and obstructive hydrocephalus that responded well to conservative management with no residual neurological deficit. Wide recognition of this treatable clinical entity among neurologist would avert unnecessary investigations and ensure rationale management.

Hepatitis viruses in heamodialysis patients: an added insult to injury?

Hepatitis B (HBV) and hepatitis C (HCV) viruses are the most important causes of chronic liver disease in patients with end stage renal disease on hemodialysis. The prevalence of hepatitis infection among hemodialysis patients is high and varies between countries and between dialysis units within a single country. This case-control study was undertaken to estimate the occurrence of HBV and HCV infections in patients undergoing hemodialysis in our tertiary care center. All patients receving hemodialysis at our centre with HCV or HBV infection were included in the study. The total number of patients admitted for hemodialysis during the study period was 1710. Among these, 26 patients were positive for HBV, 19 were positive for HCV, and 2 were positive for both HCV and HBV. Mean age of the infected cases in our study was 48.63 years. Mean duration of dialysis for infected cases was 4.8 years while that of the noninfected controls was 3.18 years. The mean dialysis interval was twice a week. Interventions to reduce the occurrence of these infections are of utmost need to reduce the risk of long-term complications among hemodialysis patients.