Sequencing of SARS-CoV-2 in local transmission cases through Oxford Nanopore MinION platform from Karachi Pakistan.

INTRODUCTION: The first case of severe acute respiratory syndrome 2 (SARS-CoV-2) was imported to Pakistan in February 2020, since then 8,260 deaths have been witnessed. The virus has been constantly mutating and local transmission cases from different countries vary due to host dependent viral adaptation. Many distinct clusters of variant SARS-CoV-2 have been defined globally. In this study, the epidemiology of SARS-CoV-2 was studied and locally transmitted SARS-CoV-2 isolates from Karachi were sequenced to compared and identify any possible variants. METHODOLOGY: The real time PCR was performed on nasopharyngeal specimen to confirm SARS-CoV-2 with Orf 1ab and E gene as targets. The virus isolates were sequenced through oxford nanopore technology MinION platform. Isolates from the first and second wave of COVID-19 outbreak in Karachi were compared. RESULTS: The overall positivity rate for PCR was 26.24% with the highest number of positive cases in June. Approximately, 37.45% PCR positive subjects aged between 19-40 years. All the isolates belonged to GH clade and shared missense mutation D614G in spike protein linked to increased transmission rate worldwide. Another spike protein mutation A222V coexisted with D614G in the virus from the second wave of COVID-19. CONCLUSIONS: Based on the present findings it is suggested that the locally transmitted virus from Karachi varies from those reported from other parts of Pakistan. Slight variability was also observed between viruses from the first and second wave. Variability in any potential vaccine target may result in failed trials, therefore information on any local viral variants is always useful for effective vaccine design and/or selection.

A distinct molecular mutational profile and its clinical impact in essential thrombocythemia and primary myelofibrosis patients.

BACKGROUND: Classical MPNs including ET and PMF have a chronic course and potential for leukaemic transformation. Timely diagnosis is obligatory to ensure appropriate management and positive outcomes. The aim of this study was to determine the mutational profile, clinical characteristics and outcome of ET and PMF patients in Pakistani population. METHODS: This was a prospective observational study conducted between 2012 and 2017 at NIBD. Patients were diagnosed and risk stratified according to international recommendations. Response to treatment was assessed by IWG criteria. RESULTS: Of the total 137 patients analysed, 75 were ET and 62 were PMF. JAK2 positivity was seen in 51 cases (37.2%), CALR in 41 cases (29.9%), while triple-negative in 17 (12.4%) cases. None of the patients in the present study were MPL positive. Overall survival for patients with ET and PMF was 92.5 and 86.0% respectively and leukaemia free survival was 100 and 91.6% respectively, at a median follow-up of 12 months. Leukaemic transformation occurred in 6.5% of MF patients; among them, JAK2 mutation was frequently found. Molecular mutations did not influence the OS in ET whereas in PMF, OS was shortest in the triple-negative PMF group as compared to the JAK2 and CALR positive patient groups. CONCLUSION: This study shows a different spectrum of molecular mutations in ET and PMF patients in Pakistani population as compared to other Asian countries. Similarly, the risk of leukaemic transformation in ET and PMF is relatively lower in our population of patients. The factors responsible for these phenotypic and genotypic differences need to be analysed in large scale studies with longer follow-up of patients.

Early and sustained deep molecular response achieved with nilotinib in high Sokal risk chronic myeloid leukemia patients.

BACKGROUND: Nilotinib (Tasigna®) is a second-generation tyrosine kinase inhibitor that shows faster and deeper molecular responses (MR) in comparison to Imatinib as initial therapy in chronic phase chronic myeloid leukemia (CML). Efficacy and safety data for nilotinib in the Asian population is scarce, particularly in Pakistan. We aimed to determine the MR to nilotinib and its safety profile in patients with chronic phase CML. PATIENTS AND METHODS: This observational study was conducted among 173 patients with newly diagnosed CML presenting in the chronic phase. Most patients (50.1%) had a high Sokal score at diagnosis. All patients received nilotinib 600 mg/day. The hematological and molecular responses were assessed at 3 and 6 months respectively and thereafter at 6-monthly intervals. Long-term event free survival (EFS), transformation free survival (TFS), overall survival (OS) and adverse events were observed. RESULTS: Cumulative incidence of major MR (MMR) was 86% and deep MR (DMR ie MR 4.0 and MR4.5) was 39%. Early MMR and DMR after 6 months of therapy were achieved by 74.9% and 37% of patients, respectively. Two-year EFS, TFS and OS rates for all patients were 91.9%, 92% and 92.3%, respectively. At median follow-up of 24 months, 81% and 49% of patients sustained MMR and DMR, respectively. The main adverse events were weight gain (4.6%) and abdominal pain (4%). CONCLUSION: This study showed promising results in terms of achievement of early and sustained DMR in chronic phase CML, therefore, we recommend nilotinib as frontline treatment in Pakistani population.

Genomic profile of a patient with triple negative essential thrombocythemia, unresponsive to therapy: A case report and literature review.

Clonal analysis of patients with triple negative myeloproliferative neoplasm (MPN) has provided evidence of additional aberrations, including epigenetic alterations. To discover such novel genetic aberrations, patients were screened through next-generation sequencing using a myeloid sequencing panel of 54 genes using a genetic analyser. Genetic variants in 28 genes, including TET2, BCOR, BCR, and ABL1 were identified in a triple negative essential thrombocythemia (ET) patient. The individual role of some of these variants in disease pathogenesis has yet to be studied. Somatic mutations in the same genes have been reported with variable frequencies in myeloid malignancies. However, no pathogenic impact of these variants could be found; therefore, long-term follow up of patients with genetic analysis of a large cohort and the use of whole genome sequencing is required to assess the effects of these variants.

Laboratory Diagnosis of Malaria: Comparison of Manual and Automated Diagnostic Tests.

Malaria is the second most prevalent disease in Pakistan resulting in ~30,000 annual deaths. In endemic countries like Pakistan precise and timely diagnosis of malaria is imperative to overcome the associated risks of fatal outcomes. Malarial parasite was screened in 128 malaria suspected patients and 150 healthy controls, by species-specific PCR, microscopy of blood smears, hemoanalyzer Sysmex XE-2100, and rapid test devices (First Response Malaria® and ICT Malaria Combo®). The microscopy detected MP in 126 samples (parasite load/µl 386-53712/µl); 71.094% were infected with Plasmodium vivax and 14.844% with P. falciparum while 14.062% had mixed P. vivax and P. falciparum infection. The mean parasite load for P. vivax and P. falciparum was 14496/µl and 24410/µl, respectively. The abnormal scattergrams of DIFF, WBC/ Baso, IMI channel, and RET-EXT on Sysmex XE-2100 supported 99.2% parasite detection, whereas only 93% of confirmed malaria cases were detected by both rapid tests. About 127 samples were positive by PCR. Since Sysmex XE-2100 automatically detected the presence of malarial parasite with high sensitivity, it can be a good option for presumptive diagnosis in endemic areas. Microscopy remains the gold standard to confirm MP in suspected patients. Rapid diagnostic tests have acceptable sensitivity and specificity.