Confirmation and follow up of initial "NAT yields": Prospective study from a tertiary healthcare center in India.

BACKGROUND: In India variable rate of "NAT yield" has been demonstrated in several published reports. This study was performed with the objective to know the rate of "true NAT yield" in blood donors by confirmation with supplementary tests and follow up of initial "NAT yield" donors. MATERIALS AND METHODS: A total of 48,441 blood donors were tested for HIV, HBV and HCV with enhanced chemiluminescence and ID-NAT. To know the true NAT yield status confirmation of NAT yield donors was done as with an array of serological tests, repeat ID-NAT and alternate NAT. RESULTS: The cumulative initial "NAT yield" rate was 1:4404 (11/48,441). Seven of 11 initial "NAT yields" were for hepatitis B whereas two each were in HIV and HCV. Among the 11 "NAT-yield" donors, eight donors were followed-up for confirmation. Out of these eight donors only 4 were found to be true HBV NAT yields. Out of four true NAT yields two were window period donations while the other two were occult hepatitis B infection with anti-HBcore total positive. CONCLUSION: Our findings suggest that all "initial NAT yields" may not be "true NAT yields". We would also like to suggest that to demonstrate the true "NAT yield" status supplementary tests and donor follow up are important to differentiate true NAT yields.

Enhanced hepatitis B virus (HBV) pre-genomic RNA levels and higher transcription efficiency of defective HBV genomes.

Defective hepatitis B virus (dHBV) particles contain genomes corresponding to singly spliced HBV RNA. A limited number of studies show that dHBV is present in all chronically HBV-infected patients. Clinical studies have linked dHBV and dHBV gene products to high virus loads and liver damage. The replication characteristics of dHBV genomes remain poorly understood. We found that the splice donor/acceptor sites critical for the formation of dHBV genomes are conserved across HBV genotypes. We report a novel method to create dHBV constructs from corresponding wild-type (WT) HBV constructs. We assessed the transcriptional characteristics of the dHBV constructs with those of the corresponding WT construct using a cell culture model. Interestingly, dHBV constructs had higher pre-genomic RNA levels, transcription efficiency, HBV e antigen levels and intracellular HBV core antigen levels compared with the corresponding WT HBV constructs. Our findings highlight previously unrecognized fundamental molecular characteristics of dHBV genomes and their potential role in the pathogenesis of HBV infection.

Etiology and survival of aplastic anemia: a study based on clinical investigation.

BACKGROUND: Management of aplastic anemia is etiology driven, whether constitutional or acquired. Age, gender, and severity of disease also play crucial role in the survival of aplastic anemia. Since, inadequate data are available from India, the present study was conducted with the aim to evaluate the etiology and survival of aplastic anemia. METHODS: Three hundred patients were enrolled between May 2007 and April 2010. Severity analysis and chromosomal breakage study was performed and patients were followed up to calculate the survival rate. RESULTS: Only 9.4% of the cases demonstrated the evidence of constitutional disease. Patients with acquired disease showed a significantly higher odd ratio for hepatitis. Overall survival was found to be independent of the gender and inherited etiology. Phenotype resembling to constitutional disease was present in only 22.22% (6/27) of patients. Similar ratio of the constitutional and acquired disease in both the age groups was observed. CONCLUSION: Irrespective of the age and phenotype, chromosomal breakage study should be mandatory for all patients with aplastic anemia. Hepatitis as a preceding event may be associated with the cause of aplastic anemia. Young age and less severe disease were strongly associated with better survival. Lack of tertiary care facility in the country, time lag between diagnosis and treatment, and unaffordability to abide the treatment cost could be the major contributory factors for poorer survival.

Prospective multi-centric study to analyze pre-transplant compatibility algorithm for live-related donor kidney transplant in Indian setting: the "Delhi approach"!

BACKGROUND: Since no single test is always accurate and sensitive, two or more tests are used to increase the precision of evaluation. Different algorithms have been proposed by centers in Leiden, Basel, Vienna and Minnesota, etc. With an intention to develop an optimal algorithm for India, we evaluated pre-transplant compatibility tests for live-donor kidney transplants. Three tests complement dependent cyto-toxicity cross-match (CDCXM), flow-cytometry cross-match (FCXM) and anti-HLA antibody screening (HAS) were performed and confirmed by the anti-HLA antibody identification (HAI) assay in a multi-centric trial (three transplant centers) in India. MATERIALS AND METHODS: All prospective recipients (and their potential donors) underwent low-resolution HLA typing as well as CDCXM, FCXM and HAS assays. In addition, HAI {single antigen bead assay; (SAB)} was done for all recipients to identify possible anti-HLA antibodies. In a virtual cross-match (VXM), antibody specificity was mapped to donor HLA type to determine donor-specific antibodies (DSA). Only patients without DSA were cleared for the transplant. Alternatively, patients with DSA were offered an exchange in the kidney paired donation (KPD) program. The screening results (CDCXM, FCXM, and HAS) were analyzed, individually as well as in combination of screening assays (CDCXM+HAS, CDCXM+FCXM, and FCXM+HAS) and the results were compared with those from the HAI test. RESULTS: Out of 100 patients, 69 were males and 31 were females; 85 recipients (85%) underwent a kidney transplant. The sensitivity of CDCXM was only 12.1% and the specificity of CDCXM was 100%; whereas the sensitivity of FCXM was 84.8% and the specificity of FCXM was 89.6%. The sensitivity and specificity of class I HAS was 88.2% and 84.3%, respectively. The sensitivity and specificity class II HAS was 88.0% and 80.0%, respectively. However, when both class I/II HAS were tested together the sensitivity increased to 97.0% and the specificity to 82.1%. Similarly, the sensitivity of combined FCXM+HAS had the sensitivity of 100% and the specificity of 76.1%; CDCXM+FCXM had the sensitivity of 84.8% and the specificity of 89.6% and CDCXM+HAS assays reached 97% with the specificity of 82.1%. CONCLUSIONS: Our results showed that the algorithm of FCXM with HAS produced the best sensitivity of 100%. The specificity of 76.1% indicate that the combined FCXM+HAS assays may detect up to 24.9% false positive results. We suggest that these false-positives may be easily resolved by performing the virtual crossmatch based on HAI (SAB) results. In our reflex testing algorithmic approach only 49% patients needed HAI (SAB). Finally, our results suggested that the CDCXM assay may be discontinued in pre-transplant workup owing to its very low sensitivity (12.1%).

Long-Term Ophthalmic Outcomes in Pediatric Orbital Cellulitis: A Prospective, Multidisciplinary Study From a Tertiary-Care Referral Institute.

PURPOSE: To analyze the clinical profile, radiological features, and ophthalmic outcomes of the multidisciplinary management of children with pediatric orbital cellulitis. METHODS: A prospective, interventional study of patients diagnosed as having pediatric orbital cellulitis was conducted. A complete history, clinical examination, laboratory work-up, radiology (computed tomography [CT]), multidisciplinary consultations (otolaryngology, pediatrics, and microbiology), and treatment plan were obtained for all children. The patients were admitted to the hospital and administered intravenous broad-spectrum antibiotics. Orbital and subperiosteal abscesses were drained via an endonasal or external route. Functional endoscopic sinus surgery was performed when necessary. After a minimum follow-up of 12 months, visual acuity, pupillary reaction, extraocular movements, and proptosis were evaluated as the outcome measures. RESULTS: Forty patients (male = 28, 70%) had unilateral presentation of pediatric orbital cellulitis at a mean age of 7.5 years (range: 4 to 12 years). At presentation, all patients had eyelid edema, conjunctival congestion, and chemosis: 38 (95%) had proptosis, 36 (90%) had decreased extraocular movements and pain, 16 (40%) had a relative afferent pupillary defect, and 6 (15%) had exposure keratitis and optic disc edema. CT scans showed sinusitis in 30 (75%) patients, orbital abscess in 14 (35%) patients, and subperiosteal abscess in 5 (12.5%) patients. At a mean follow-up of 15 months, 30 (75%) patients had complete success, 8 (20%) patients had partial success, and the treatment failed in 2 (5%) patients. No patient had any life-threatening complications. CONCLUSIONS: The multidisciplinary management of pediatric orbital cellulitis provides satisfactory long-term ophthalmic outcomes. Ethmoidal sinusitis is the most common etiology of pediatric orbital cellulitis, and endoscopic abscess drainage and functional endoscopic sinus surgery are minimally invasive and provide rapid relief in children. [J Pediatr Ophthalmol Strabismus. 2019;56(5):333-339.].

Combination of capsular tension ring and capsular tension segment for the management of lens coloboma >4 clock hours.

Lens colobomas extending more than 4 clock hours and causing visual impairment require lens extraction along with capsular support devices with scleral fixation for adequate centration of the capsular bag and for prevention of capsular fornix aspiration with inadvertent extension of zonular dialysis intraoperatively. In this case series, we describe a technique for the management of isolated lens colobomas involving 4-5 clock hours by clear lens extraction and intraocular lens implantation using a combination of a capsular tension ring with a capsular tension segment (CTS) for the centration and stability of the capsular bag. Hoffman's corneoscleral pocket and half-bow sliding knot technique were used for scleral fixation of the CTS.

Immune keratitis: An unusual primary presentation of neuro-Behçet's disease.

A 19-year-old Nepalese male presented with complaints of bilateral ocular discomfort, photophobia, watering, and redness for 1 week. Visual acuity was 6/12 and 6/60 in the right and left eye, respectively. On biomicroscopic examination, presence of peripheral stromal infiltrates with conjunctival follicles was noted; infiltrates progressed to involve central cornea with further decrease in vision over next few days. After ruling out infectious keratitis, detailed systemic examination and laboratory investigations were diagnostic of neuro-Behçet's disease. Patient responded to systemic steroidal and immunosuppressive therapy characterized by corneal healing and visual acuity improvement to 6/6 and 6/9. Although rare, but neuro-Behçet's disease can primarily present as bilateral immune keratitis and every case of bilateral keratitis needs early systemic evaluation after ruling out infective etiologies.

Establishing a sample-to cut-off ratio for lab-diagnosis of hepatitis C virus in Indian context.

INTRODUCTION: Lab-diagnosis of hepatitis C virus (HCV) is based on detecting specific antibodies by enzyme immuno-assay (EIA) or chemiluminescence immuno-assay (CIA). Center for Disease Control reported that signal-to-cut-off (s/co) ratios in anti-HCV antibody tests like EIA/CIA can be used to predict the probable result of supplemental test; above a certain s/co value it is most likely to be true-HCV positive result and below that certain s/co it is most likely to be false-positive result. A prospective study was undertaken in patients in tertiary care setting for establishing this "certain" s/co value. MATERIALS AND METHODS: The study was carried out in consecutive patients requiring HCV testing for screening/diagnosis and medical management. These samples were tested for anti-HCV on CIA (VITROS(®) Anti-HCV assay, Ortho-Clinical Diagnostics, New Jersey) for calculating s/co value. The supplemental nucleic acid test used was polymerase chain reaction (PCR) (Abbott). PCR test results were used to define true negatives, false negatives, true positives, and false positives. Performance of different putative s/co ratios versus PCR was measured using sensitivity, specificity, positive predictive value and negative predictive value and most appropriate s/co was considered on basis of highest specificity at sensitivity of at least 95%. RESULTS: An s/co ratio of ≥6 worked out to be over 95% sensitive and almost 92% specific in 438 consecutive patient samples tested. CONCLUSION: The s/co ratio of six can be used for lab-diagnosis of HCV infection; those with s/co higher than six can be diagnosed to have HCV infection without any need for supplemental assays.