(a) (i) How do you differentiate between acute lymphoblastic leukaemia (ALL) and acute myeloid leukaemia (AML) based on…

(a)(i) ALL and AML are differentiated by lineage of blasts on peripheral smear and marrow, using FAB morphology and WHO immunophenotypic and cytogenetic criteria. FAB classifies ALL as L1-L3 and AML as M0-M7, but WHO adds immunophenotype and cytogenetics. In ALL, peripheral smear shows lymphoblasts with high nuclear-to-cytoplasmic ratio, scant agranular cytoplasm, condensed chromatin and no Auer rods; immunophenotyping is TdT positive, with B-cell or T-cell markers. In AML, myeloblasts have more cytoplasm, fine chromatin, nucleoli, primary granules and Auer rods; they are myeloperoxidase and Sudan black B positive and express CD13/CD33. Peripheral smear may show circulating blasts in both, but morphology and immunophenotype identify lineage; marrow shows suppression of normal trilineage maturation. Bone marrow is hypercellular with maturation arrest in both, and marrow aspirate is required to quantify blasts. WHO generally uses a blast threshold of 20% or more for ALL and AML, except AML with defining recurrent genetic abnormalities such as t(15;17), t(8;21) or inv(16), which can be diagnosed irrespective of blast percentage. Cytogenetics further separate them: Philadelphia chromosome/BCR-ABL1 is characteristic of some ALL, while t(8;21) and inv(16) are recurrent AML abnormalities.

(a)(ii) Current ALL therapy is age- and risk-stratified. In children, protocols based on NCI/CCLG criteria use induction with vincristine, dexamethasone, L-asparaginase and doxorubicin, followed by consolidation, delayed intensification, CNS prophylaxis with intrathecal methotrexate, and prolonged maintenance with 6-mercaptopurine and methotrexate. Risk groups are defined by age, presenting white-cell count, CNS involvement and cytogenetics. Remission is assessed by marrow, and therapy is continued according to response and risk. In adults, standard regimens include hyper-CVAD or pediatric-inspired combinations; Ph+ ALL is treated with chemotherapy plus a tyrosine kinase inhibitor such as imatinib or ponatinib, and allogeneic haematopoietic stem-cell transplantation is considered in high-risk or Ph+ disease, often in first remission. For relapsed or refractory B-ALL, blinatumomab, inotuzumab ozogamicin and CAR-T cell therapy, especially tisagenlecleucel in children and young adults, are used to achieve remission before transplant where eligible.

(b) The National Immunization Schedule under the Universal Immunization Programme for children includes BCG; OPV and IPV; hepatitis B vaccine; DPT and DPT boosters; pentavalent vaccine; PCV; rotavirus vaccine; measles/MMR vaccine; JE vaccine; and OPV boosters. These include live attenuated vaccines such as BCG, OPV, MMR and JE, and inactivated, subunit or conjugate vaccines such as IPV, hepatitis B, DPT, pentavalent and PCV. An adverse event following immunization is any untoward medical occurrence after vaccination, whether or not causally related to the vaccine. AEFI reporting supports vaccine safety surveillance. Examples: DPT may cause local sterile abscess, high febrile reaction, hypotonic-hyporesponsive episode or encephalopathy; measles/MMR may cause fever, febrile seizures, rash or thrombocytopenia; OPV may cause vaccine-associated paralytic poliomyelitis.

(c) Renovascular hypertension is suspected when hypertension begins before 30 or after 55 years, is resistant, has an abdominal bruit, or presents with flash pulmonary oedema or unexplained kidney injury. Screening is usually Doppler ultrasound of renal arteries; CTA or MRA confirms stenosis, while catheter-based renal angiography remains the gold standard and allows intervention. Management depends on aetiology. In fibromuscular dysplasia, percutaneous transluminal renal angioplasty, with stenting if needed, is curative and first-line. In atherosclerotic renal artery stenosis, optimal medical therapy with antihypertensives, ACE inhibitors or ARBs with caution in bilateral stenosis, statins, antiplatelet therapy and risk-factor control is the cornerstone; revascularization is reserved for refractory hypertension, recurrent flash pulmonary oedema, acute kidney injury, or severe bilateral/solitary-kidney disease, and may be endovascular or surgical. Surgical revascularization is considered for selected atherosclerotic lesions, such as long-segment or complex stenosis, or failed endovascular therapy. Thus, curative PTRA is preferred for FMD, while atherosclerotic disease is managed medically first, with revascularization only for selected indications.