SARS-CoV-2 vaccine responses following CD20-depletion treatment in patients with haematological and rheumatological disease: a West Midlands Research Consortium study.

B-cell-depleting agents are among the most commonly used drugs to treat haemato-oncological and autoimmune diseases. They rapidly induce a state of peripheral B-cell aplasia with the potential to interfere with nascent vaccine responses, particularly to novel antigens. We have examined the relationship between B-cell reconstitution and SARS-CoV-2 vaccine responses in two cohorts of patients previously exposed to B-cell-depleting agents: a cohort of patients treated for haematological B-cell malignancy and another treated for rheumatological disease. B-cell depletion severely impairs vaccine responsiveness in the first 6 months after administration: SARS-CoV-2 antibody seroprevalence was 42.2% and 33.3% in the haemato-oncological patients and rheumatology patients, respectively and 22.7% in patients vaccinated while actively receiving anti-lymphoma chemotherapy. After the first 6 months, vaccine responsiveness significantly improved during early B-cell reconstitution; however, the kinetics of reconstitution was significantly faster in haemato-oncology patients. The AstraZeneca ChAdOx1 nCoV-19 vaccine and the Pfizer BioNTech 162b vaccine induced equivalent vaccine responses; however, shorter intervals between vaccine doses (<1 m) improved the magnitude of the antibody response in haeamto-oncology patients. In a subgroup of haemato-oncology patients, with historic exposure to B-cell-depleting agents (>36 m previously), vaccine non-responsiveness was independent of peripheral B-cell reconstitution. The findings have important implications for primary vaccination and booster vaccination strategies in individuals clinically vulnerable to SARS-CoV-2.

Vitamin B12 deficiency--a major cause of megaloblastic anaemia in patients attending a tertiary care hospital.

BACKGROUND: Folate and vitamin B12 deficiencies have been known to cause megaloblastic anaemia. Since the deficiencies of these two vitamins are very common in Pakistani population, it would be imperative to investigate their role in causing megaloblastic anaemia. The objective of this study was to find out the contribution of folate and vitamin B12 deficiencies in causing megaloblastic anaemia in our patient population. METHODS: In this retrospective cohort study, clinical records of 220 patients (101 females and 119 males with an age range of 1-80 years) who presented themselves with macrocytic anaemia at the Aga Khan University Hospital were collected. Data pertaining to complete blood count and serum levels of folate and vitamin B12 were analysed. RESULTS: The mean haemoglobin (Hb) level was 6.8 +/- 0.2 gm/dl. Sixty-nine percent of the patients had severe anaemia (Hb < 8 gm/dl). Mean +/- SEM values of haemoglobin, serum folate and serum B12 were not significantly different between males and females (Hb 6.4 +/- 0.3 gm/dl vs 6.3 +/- 0.3 gm/dl; folate 6.9 +/- 0.8 etag/ml vs 7.8 +/- 1 etag/ml; B12 259 +/- 65 rhog/ml vs 225 +/- 45 rhog/ml, respectively). Linear regression analysis showed that serum folate was inversely related with the mean corpuscular volume (MCV, p = 0.04). Spearman's correlation analysis indicated an inverse mild association between MCV and serum folate (correlation coefficient = -0.18). Folate deficiency was 43.4%, while vitamin B12 deficiency was 78.5% in these patients. Seventy-one percent of folate-deficient patients had vitamin B12 deficiency as well, while 26.1% of patients with B12 deficiency had a co-occurrence of folate deficiency. CONCLUSION: Vitamin B12 deficiency appears to be the major factor leading to megaloblastic anaemia in our study population. Inadequate dietary intake, over-cooking of our food and poor absorption might be contributing to high prevalence of vitamin B12 deficiency in this population.

Extranodal non-Hodgkin's lymphomas--a retrospective review of clinico-pathologic features and outcomes in comparison with nodal non-Hodgkin's lymphomas.

OBJECTIVE: The primary objective of this study was to analyze the anatomic distribution, clinical features and outcome of Diffuse large B-cell lymphoma (DLBCL) patients according to the primary site (extranodal vs. nodal) with applicability of International Prognostic Index (IPI). METHODOLOGY: A retrospective review (1988 to 2004) of 557 cases of DLBC. RESULTS: The median age was 48.7 +/- 15.3 years; M:F ratio was 2:1. The distribution according to the primary site was: lymph node (N-NHL), 322 cases (58%) of which 145(44%) were stage IV, 76(23%) stage III, 60 (18%) stage II and 47 (15%) stage I. The extra nodal sites (EN-NHL) 235 (42%) cases included gastro-intestinal tract (44%), upper aerodigestive tract (19%), bones (8%), spine (5%), and unusual sites less than 3% each as breast, CNS, testis, lungs and skin. The median survival rate was 4.8 years and 6.3 years in N-NHL and EN-NHL respectively. In the latter this varied greatly depending on the primary site and stage of disease at presentation. In the univariate analysis factors associated with good prognosis were: age less than 60 years, early stage (I-II), extranodal involvement primarily gastric or bone, 0-1 extranodal site, 0-1 performance status, lack of B symptoms and normal LDH level. In the multivariate analysis age, performance status, stage of disease and level of LDH were the main variables predicting overall survival; no nodal or extranodal site maintained their prognostic value. CONCLUSION: Patients with EN-NHL present more frequently with early stage disease then those with N-NHL; overall survival in both groups largely depended on IPI and not on the site of origin of the malignancy.

Chronic ITP: analysis of various factors at presentation which predict failure to first line treatment and their response to second line therapy.

OBJECTIVE: To observe the significance of various factors in chronic idiopathic thrombocytopenic purpura (ITP) which predict the response of first line (corticosteroids) and second line therapy (splenectomy) and to evaluate their response to second line therapy. METHODS: This was a descriptive, prospective study conducted from August 2004 till January 2006. Patients of all age groups and both genders with diagnosis of chronic ITP were included. Treatment protocol and criteria for response assessment was explained. RESULTS: During 17 months period, 86 patients with chronic ITP were analyzed. Non-responders to first line therapy were 74 patients who ultimately required splenectomy. Complete response (CR) was had in 37 (50.7%) patients, 10 (13.7%) and 27 (36.5%) had partial response (PR) and no response (NR) respectively. Analysis of variables like younger age, sex and low platelet count at presentation failed to show any significant influence on response to first line treatment. However response to splenectomy was found to be higher in patients who had initial complete or partial response with steroids and later relapsed and the platelet count was more than 300x10(9)/L on day 14 of surgery. CONCLUSION: Splenectomy remains the most effective treatment of chronic ITP. No significant factor was identified which predicted initial response to first line treatment. However patients who initially responded to steroids and had platelet counts above 300 X109/L about a fortnight after splenectomy showed promising results post-operatively (p=0.003 and p=0.001).

Role of ICT malaria immunochromatographic test for rapid diagnosis of malaria.

OBJECTIVE: To evaluate the sensitivity and specificity of immunochromatographic test (ICT) malaria p.f/p.v using microscopy as the gold standard diagnosis. METHODS: Five hundred and sixty patients of both sexes and all age groups with clinical suspicion of malaria were studied. Venous blood was collected for microscopy and ICT. Thick and thin films prepared and stained with Leishman's stain were examined. ICT malaria test was performed and interpreted according to manufacturer's instructions. Data was analyzed using Epi-6. RESULTS: A total of 560 cases were studied, 339 males and 221 females with age ranges between 2 to 73 years. Seventy two (12.85%) cases had parasitaemia (with or without sexual forms). On microscopy 65 (11.6%) cases had asexual-stage parasitaemia and 7 (1.25%) cases had P. falciparum gametocytes only. Thirty two cases were infected with P. falciparum, 29 with P. vivax and 4 had mixed infection. For P. falciparum the ICT was 97.0% sensitive, 98.3% specific, with positive predictive value (PPV) of 78.0% and a negative predictive value (NPV) of 99.8%. For P. vivax the sensitivity was only 89.7%, specificity 97.9%, PPV was 70.3% and NPV 99.4%. CONCLUSION: Our results are in concordance with previous studies. Rapid tests though expensive are simple to perform and effective diagnostic tools of malaria. They can be used selectively, though microscopy remains the gold standard diagnosis, economical and accurate if performed by skilled technologists.

Significance of cytogenetic abnormalities in acute myeloid leukaemia.

OBJECTIVE: To evaluate the role of karyotype in acute myeloid leukaemia (AML) as a predictor of response to induction chemotherapy. METHODS: A cross-sectional study was carried out at the department of Pathology and Oncology, Aga Khan University Karachi from January 2003 to January 2005. Newly diagnosed patients with denovo AML admitted to the hospital were included in the study. Diagnosis of AML was based on FAB criteria, immunophenotyping and cytogenetic studies. They were treated according to standard protocols (combination of anthracycline and cytarabine -3+7) and those who had acute promyelocytic leukaemia additionally received all- trans retinoic acid (ATRA). RESULTS: A total of 56 patients were enrolled, 4 were excluded due to inadequate cytogenetic analysis and the remaining patients entered the study protocol. There were 32 males and 20 females with mean age of 31.3 years (range 9 months to 73 years). Thirty-five (67.3%) patients had normal karyotype while 17 (32.7%) were found to have cytogenetic abnormalities. Eleven patients did not receive treatment at our hospital. Half of the (51.2%) patients out of remaining 41 achieved complete remission on bone marrow examination after receiving induction chemotherapy. In favourable risk group 3/3 (100%) achieved complete remission (CR) while 15/32 (46.9%) in intermediate risk group and 3/6 (50%) in unfavourable risk group. There was low CR rate in patients with high white cell counts. CONCLUSION: The frequency of cytogenetic abnormalities in AML and response to induction chemotherapy was low when compared with international data possibly due to the small sample size. However, there was a clear difference in CR rates between favourable and unfavourable risk groups.

Frequency of fab subtypes in acute myeloid leukemia patients at Aga Khan University Hospital Karachi.

BACKGROUND: Acute myeloid leukemia (AML) is a heterogeneous disease. Therefore, various parameters are needed to classify this disease into subtypes, so that specific treatment approaches can be utilized effectively. The commonly used method for diagnosis and classification is based on FAB criteria using morphology and cytochemical stains. For some of the categories, immunophenotyping is necessary. The aim of present study is to determine the frequency of various sub types in acute myeloid leukemia using FAB criteria in our population. This will aid in the correct diagnosis of acute leukemia and hence proper management of the patients. MATERIALS AND METHODS: This is descriptive case control study conducted at Aga Khan University Hospital from January 1999 to December 2000. The total number of subjects was 116 that included both adults and children. The patients were diagnosed on the basis of bone marrow morphology using FAB classification. Cytochemistry was done in all cases, while immunophenotyping was considered only in those cases that were found to be problematic. RESULTS: Among 116 patients, 70 were males and 46 were females with male to female ratio 1.5:1. The age ranged between 6 months to 85 years with a mean age of 32 years. AML-M4 was the predominant French-American-British (FAB) subtype (36.2%) followed by M2 (30.25%), M3 (10.4%), M1 (8.7%), M0 (7.7%), M5a (3.5%), M5b (2.5%) and M6 (0.8%). CONCLUSIONS: The most common FAB subtype observed in our study was Acute myelomonocytic leukemia (M4) which is in accordance with studies reported from Saudia Arabia and a previous study reported from our institution. However,other national and international studies have reported Myeloblastic Leukemia with maturation (M2) as the predominant subtype of AML.

Frequency of irregular red cell alloantibodies in patients with thalassemia major: a bicenter study.

OBJECTIVE: To provide frequency and distribution pattern of various types of irregular red cell alloantibodies in patients with thalassemia major. METHODS: This is a descriptive study conducted at two centers from January to December 2001. Purposive sampling was done and all patients diagnosed to have thalassemia major were included in the study. Antibody identification was carried out on serum employing commercial two-cell panel using standardized blood bank methods. If patients were found to have an irregular red cell alloantibody then the antibody identification was performed using 16 panel cells. RESULTS: A total of ninety-seven patients were included in the study. Fifty-three patients were males and 44 females. Mean age was 10.6 years. Irregular red cell alloantibodies were found in 9 (9.2%). Mean age of patients who developed red cell alloantibody was 11.9 years. Three (33.3%) patients developed anti-K while two (22.2%) had non-specific antibody. One patient each developed anti-D (11.1%) and anti-E (11.1%). Two had anti-D (11.1%) and anti-C while the other one (11.1%) developed anti-E and anti-K. CONCLUSION: We concluded that there is relatively high rate of alloimmunization in our set of patients when compared to data from our region. We also suggest that red cell alloimmunization should not be overlooked in patients receiving regular blood transfusions.

Myocardial infarction during factor IX infusion in hemophilia B: case report and review of the literature.

There are very few reports in the literature of acute myocardial infarction (MI) occurring during infusion of factor concentrates, particularly cryosupernatant in patients with hemophilia B. We describe a case of a 61-year-old man with hemophilia B who suffered an acute MI while receiving cryosupernatant infusion as factor replacement therapy. Cryosupernatant is rich in coagulation factor IX and contains low levels of fibrinogen and von Willebrand's factor. Factor IX and other factors present in cryosupernatant can possibly become activated during the manufacturing process causing thrombus formation in patients who are prone to it.