Validation of a Simple-to-Use, Affordable, Portable Wavefront Aberrometry-Based Auto Refractometer in a Paediatric Population.

Purpose: InstaRef R20 is a handheld, affordable auto refractometer based on Shack Hartmann aberrometry technology. The study's objective was to compare InstaRef R20's performance for identifying refractive error in a paediatric population to that of standard subjective and objective refraction under both pre- and post-cycloplegic conditions. Methods: Refraction was performed using 1) standard clinical procedure consisting of retinoscopy followed by subjective refraction (SR) under pre- and post-cycloplegic conditions and 2) InstaRef R20. Agreement between both methods was evaluated using Bland-Altman analysis. The repeatability of the device based on three measurements in a subgroup of 20 children was assessed. Results: The refractive error was measured in 132 children (mean age 12.31 ± 3 years). The spherical equivalent (M) and cylindrical components (J0 and J45) of the device had clinically acceptable differences (within ±0.50D) and acceptable agreement compared to standard pre- and post-cycloplegic manual retinoscopy and subjective refraction (SR). The device agreed within ± 0.50D of retinoscopy in 67% of eyes for M, 78% for J0 and 80% for J45 and within ± 0.50D of SR in 70% for M and 77% for cylindrical components. Conclusion: InstaRef R20 has an acceptable agreement compared to standard retinoscopy in paediatric population. The measurements from this device can be used as a starting point for subjective acceptance. The device being simple to use, portable, reliable and affordable has the potential for large-scale community-based refractive error detection.

IgA nephropathy in Kerala, India: a retrospective study.

This study was conducted to assess the prevalence of IgA nephropathy in Kerala. No published data are available in literature from this part of India. This study included 1592 renal biopsies received from all parts of Kerala over a 2-year period. The age of the subjects ranged from 5 to 78 years old with a peak incidence in the third decade of life. The male:female ratio was 1.2:1. A total of 60% of the cases had presented with hematuria. Direct immunoflourescence was performed using specific antibodies for IgA, IgG, IgM, C3 and C1q. Light microscopic studies with special stains namely PAS, silver and trichrome were also done. A total of 227 cases (14.26% of all renal biopsies) were diagnosed as IgA excluding 12 cases of Henoch-Schonlein Purpura (12.74% in the first year and 15.52% in the second year). The prevalence of IgA nephropathy appears to be increasing in Kerala.

Non-neoplastic renal diseases in Kerala, India--analysis of 1592 cases, a two year retrospective study.

A retrospective analysis of 1592 renal biopsies received from various hospitals all over Kerala over a period of two years was done. Of the 1544 native kidney biopsies majority of cases (300; 18.84%) were focal segmental glomerulosclerosis. Next infrequency was IgA nephropathy (227; 14.26%). The other diagnoses included post infectious glomerulonephritis (GN) (150; 9.42%), lupus nephritis (131; 8.23%), membranous glomerulonephritis (118; 7.41%), minimal change disease (94; 5.94%), interstitial nephritis 87(5.46%), membranoproliferative glomerulonephritis (MPGN) and severe glomerulosclerosis (74; 4.64% each), IgM nephropathy (72; 4.52%), acute tubular necrosis and diabetic glomerulopathy (24; 1.5% each), ANCA-related GN (21;1.32%), amyloidosis (13; 0.82%), Henoch Schonlien purpura (12; 0.75%) atd thrombotic microangiopathy (10; 0.63%). Afew others like myeloma cast nephropathy, cholesterol embolism, Clq nephropathy, oxalosis, mixed connective tissue disorder (MCTD, Wegner's granulomatosis etc. also were seen occasionally. 48 cases were allograft biopsies (3.02%).