Medical Science

UPSC Medical Science 2024 — Paper I

All 8 questions from UPSC Civil Services Mains Medical Science 2024 Paper I (400 marks total). Every stem reproduced in full, with directive-word analysis, marks, word limits, and answer-approach pointers.

8Questions
400Total marks
2024Year
Paper IPaper

Topics covered

Anatomy and Physiology - Nerve, Heart, Iron absorption, Neuromuscular junction (1)Thyroid anatomy, Vitamin D and B12, Cardiovascular physiology (1)Uterus anatomy, Protein synthesis inhibitors, Ribozymes, Dwarfism, Oogenesis (1)Facial nerve, Inguinal hernia, Renal clearance, RFLP, Anaemia, Eosinophils, Platelets (1)Pharmacology and Pathology - Antivirals, Chemotherapy, Hypersensitivity, Cancer, Diabetes complications, Injury (1)Pathology and Microbiology - Breast cancer, Tuberculosis, Malaria, Helminthiasis, Candidiasis, Shigellosis (1)Forensic Medicine and Clinical Medicine - Hanging, Liver disease, Leukaemia, Pharmacology (1)Microbiology, Forensic Medicine and Pharmacology - Enteric fever, HIV, Virtual autopsy, Brain death, Infliximab, Natriuretic peptides (1)

A

Q1
50M Compulsory describe Anatomy and Physiology - Nerve, Heart, Iron absorption, Neuromuscular junction

Describe the radial nerve under the following headings: (i) Origin and course (ii) Branches and muscles supplied (iii) Applied aspects Describe the development of ventricles of the heart. Add a note on Fallot's tetralogy. Explain the 'Mucosal Block Theory' for iron absorption. Discuss briefly the complications of excess of iron deposition in the body. Give the sequence of events at the neuromuscular junction during the transmission of a nerve impulse. Name the muscles most commonly affected by myasthenia gravis. Describe the components of the nervous system which are concerned with 'conscious alert state' that makes perception possible.

हिंदी में पढ़ें

बहिःप्रकोष्ठिका तंत्रिका का निम्नलिखित शीर्षकों के अंतर्गत वर्णन कीजिए : (i) उद्गम तथा मार्ग (ii) शाखाएँ तथा पेशियाँ जिनकी यह तंत्रिका आपूर्ति करती है (iii) अनुप्रयुक्त पहलू हृदय में निलयों के विकास का वर्णन कीजिए। फैलो चतुष्क (टेट्रालॉजी) पर एक टिप्पणी लिखिए। लोह अवशोषण का 'श्लेष्मकलारोध सिद्धांत' समझाइए। शरीर में अत्यधिक लोह निक्षेप से उत्पन्न होने वाली जटिलताओं की संक्षेप में व्याख्या कीजिए। तंत्रिका आवेग के संचरण के दौरान तंत्रिका-पेशी संगम पर होने वाली घटनाओं को क्रमवत उल्लिखित कीजिए। गंभीर पेशी-दुर्बलता (मायस्थेनिया ग्रेविस) में सर्वाधिक प्रभावित होने वाली पेशियों के नाम बताइए। तंत्रिका तंत्र के उन अवयवों का वर्णन कीजिए जो 'संजाग्रीत सतर्क अवस्था' से संबंध रखते हैं, जिससे बोध संभव हो पाता है।

Answer approach & key points

Framework: Anatomical & Physiological Description. (a) describe: define > structure or process in order > labelled diagram > significance | (b) describe: define > structure or process in order > labelled diagram > significance | (c) explain: definition/context > points in order > small example > short close | (d) describe: define > structure or process in order > labelled diagram > significance | (e) describe: define > structure or process in order > labelled diagram > significance Full marks: Comprehensive, accurate, and well-structured answers with diagrams and clinical correlations.

  • Origin: posterior cord (C5–T1); course behind axillary artery, lower triangular space, spiral groove, lateral intermuscular septum, division in front of lateral epicondyle
  • Muscular branches: triceps, anconeus, brachioradialis, ECRL, (lateral brachialis); deep branch/PIN to supinator, ECRB and forearm extensors
  • Cutaneous branches: posterior cutaneous of arm and forearm, lower lateral cutaneous of arm, superficial radial to dorsum of hand
  • Applied: crutch palsy, Saturday-night palsy, mid-shaft humerus fracture (wrist drop), PIN injury (no wrist drop), sensory loss at first dorsal web space
  • Primitive ventricle and bulbus cordis; muscular interventricular septum
  • Membranous septum from endocardial cushions, conotruncal ridges and muscular septum
  • Outflow tract separation by spiral aorticopulmonary septum
  • Fallot: anterosuperior deviation of infundibular septum ⇒ pulmonary stenosis, VSD, overriding aorta, RVH; cyanosis, boot-shaped heart
  • Fe³⁺ reduced to Fe²⁺ (duodenal cytochrome b), DMT1 uptake
  • Ferritin trapping in enterocytes; loss with shedding; ferroportin/hephaestin export
  • Hepcidin regulation of ferroportin
  • Iron overload: haemochromatosis/haemosiderosis — cirrhosis, HCC, cardiomyopathy, diabetes (bronze), hypogonadism, arthropathy, skin pigmentation
  • Nerve AP → voltage-gated Ca²⁺ influx → ACh release by exocytosis
  • ACh binds nicotinic receptors → end-plate potential → muscle AP
  • ACh hydrolysed by acetylcholinesterase
  • Myasthenia gravis: extraocular (ptosis, diplopia), facial, bulbar, neck and proximal limb muscles
  • Ascending reticular activating system (brainstem reticular formation)
  • Thalamic (intralaminar) relay to cortex
  • Neuromodulators: cholinergic, noradrenergic (locus coeruleus), serotonergic (raphe), histaminergic, orexinergic hypothalamus
  • Cerebral cortex integration for perception; effect of lesions (coma)
Q2
50M describe Thyroid anatomy, Vitamin D and B12, Cardiovascular physiology

A middle-aged female notices a lump in the midline of the neck. She notices it moves with swallowing. The surgeon gives a tentative diagnosis of goitre. Describe the thyroid gland under the following headings: (i) Gross anatomy and relations (ii) Blood supply and lymphatic drainage (iii) Surgical anatomy of thyroid gland Explain why vitamin D can be considered to be a 'hormone'. Describe the role of vitamin D in calcium homeostasis. Discuss the sources and Recommended Daily Allowance (RDA) of vitamin B12. Briefly discuss the absorption of vitamin B12 in the GIT and the clinical manifestations of the disorder of absorption of vitamin B12. Define the Frank-Starling law. State the significance and causes of shift of Frank-Starling curve to right and left. What is the role of baroreceptors and chemoreceptors in the regulation of blood pressure?

हिंदी में पढ़ें

एक मध्यमवय महिला को ग्रीवा की मध्यरेखा में अपृदुर्द दिखाई दी। यह अपृदुर्द निगलने की क्रिया के साथ स्थान बदलती थी। शल्यचिकित्सक ने इसे देख गलगंड का प्रारंभिक निदान दिया। अवटु ग्रंथि का निम्नलिखित शीर्षकों के अंतर्गत वर्णन कीजिए : (i) सकल शारीर एवं संबंध (ii) रक्त आपूर्ति तथा लसीका जल-निकासी (iii) अवटु ग्रंथि का शल्यतंत्री शारीर समझाइए कि क्यों विटामिन D को 'हार्मोन' माना जा सकता है। कैल्शियम की समस्थिति बनाए रखने में विटामिन D की भूमिका का वर्णन कीजिए। विटामिन B12 के स्रोत तथा अनुशंसित दैनिक भत्ते (आर० डी० ए०) की व्याख्या कीजिए। विटामिन B12 के जी० आई० टी० में अवशोषण तथा विटामिन B12 के अवशोषण के विकार की रोगलाक्षणिक अभिव्यक्तियों की संक्षेप में व्याख्या कीजिए। फ्रैंक-स्टारलिंग नियम को परिभाषित कीजिए। फ्रैंक-स्टारलिंग वक्र की दायीं तथा बायीं ओर स्थानांतरित होने के महत्व तथा कारणों को लिखिए। रक्तदाब के नियमन में दाबग्राहियों तथा रसायनग्राहियों की क्या भूमिका है?

Answer approach & key points

Framework: Medical Science, Paper 1. (a(i)) describe: define > structure or process in order > labelled diagram > significance | (a(ii)) describe: define > structure or process in order > labelled diagram > significance | (a(iii)) describe: define > structure or process in order > labelled diagram > significance | (b(i)) explain: definition/context > points in order > small example > short close | (b(ii)) discuss: intro > 3-4 dimensions > example > balanced close | (c(i)) define: precise definition > the distinguishing feature > one example | (c(ii)) explain: definition/context > points in order > small example > short close Full marks: Comprehensive, accurate, with diagrams and clinical correlations

  • Two lobes, isthmus over tracheal rings 2–4, pyramidal lobe
  • Capsules: true and false (pretracheal fascia); movement with swallowing
  • Anterior relations: strap muscles, sternocleidomastoid
  • Posterior/medial relations: trachea, oesophagus, larynx, RLN, parathyroids, carotid sheath laterally
  • Superior thyroid artery (ECA), inferior thyroid artery (thyrocervical trunk), thyroidea ima (variable)
  • Veins: superior and middle to IJV, inferior to brachiocephalic
  • Lymphatics: prelaryngeal (Delphian), pretracheal, paratracheal, deep cervical nodes
  • Clinical relevance of venous/lymphatic routes
  • RLN in tracheo-oesophageal groove; relation to inferior thyroid artery (ligate away from gland)
  • External laryngeal nerve with superior thyroid artery (ligate close to upper pole)
  • Parathyroid preservation with blood supply
  • Berry's ligament, capsules, tubercle of Zuckerkandl
  • Synthesised in skin; 25-hydroxylation in liver, 1α-hydroxylation in kidney (regulated by PTH)
  • Acts via nuclear VDR on distant targets — hormone criteria
  • Actions: ↑ intestinal Ca/P absorption, ↑ renal Ca reabsorption, bone mobilisation with PTH, mineralisation
  • Feedback: suppresses PTH; FGF-23 regulation
  • Sources: animal foods; vegetarians at risk; RDA ≈ 2.2 µg/day (ICMR-NIN 2020) / 2.4 µg
  • Absorption: release by pepsin, R-binder (haptocorrin), intrinsic factor, terminal ileum cubilin, transcobalamin II
  • Causes of malabsorption: pernicious anaemia, gastrectomy, ileal disease/resection, fish tapeworm, bacterial overgrowth
  • Manifestations: megaloblastic anaemia, glossitis, SACD, neuropathy, neuropsychiatric changes
  • Definition: stroke volume rises with end-diastolic volume (sarcomere length–tension)
  • Significance: matches outputs of two ventricles; adjusts to venous return
  • Left/upward shift: positive inotropes, sympathetic stimulation, catecholamines, digoxin
  • Right/downward shift: heart failure, negative inotropes, ischaemia, acidosis, increased afterload
  • Baroreceptors: carotid sinus (IX), aortic arch (X); stretch-sensitive
  • Reflex via NTS and vasomotor centre: ↑BP ⇒ ↑vagal, ↓sympathetic ⇒ ↓HR, vasodilatation
  • Chemoreceptors: carotid/aortic bodies respond to hypoxia, hypercapnia, acidosis ⇒ vasoconstriction, ↑BP (esp. BP < 80 mmHg)
  • Short-term vs long-term regulation; baroreceptor resetting
Q3
50M describe Uterus anatomy, Protein synthesis inhibitors, Ribozymes, Dwarfism, Oogenesis

Describe the uterus under the following headings: (i) Gross anatomy (ii) Ligaments and supports (iii) Relations of uterus (iv) Blood supply (v) Lymphatic drainage (vi) Applied aspects Which antibiotics and toxins inhibit protein synthesis in prokaryotes and eukaryotes? Briefly explain the mechanism of action of each of them. What are ribozymes? Explain briefly the role of any one ribozyme in protein synthesis. Enumerate the major hormonal causes of dwarfism. Give their characteristic features. Describe the principal events during oogenesis in brief.

हिंदी में पढ़ें

गर्भाशय का वर्णन निम्नलिखित शीर्षकों के अंतर्गत कीजिए : (i) सकल शारीर (ii) स्नायु एवं अवलम्ब (iii) गर्भाशय के संबंध (iv) रक्त आपूर्ति (v) लसीका जल-निकासी (vi) अनुप्रयुक्त पहलू कौन-से एंटीबायोटिक तथा कौन-से टॉक्सिन प्राकृतिककों और युक्रियकों में प्रोटीन संश्लेषण का संदमन करते हैं? प्रत्येक के कार्य करने की क्रियाविधि संक्षेप में समझाइए। राइबोजाइम क्या होते हैं? प्रोटीन संश्लेषण में किसी एक राइबोजाइम की भूमिका संक्षेप में समझाइए। बामना के प्रमुख हार्मोनल कारण गिनाइए। उनकी लाक्षणिक विशिष्टताएं बताइए। डिंबजनन में होने वाली प्रमुख घटनाओं का संक्षेप में वर्णन कीजिए।

Answer approach & key points

Framework: null. (a) describe: define > structure or process in order > labelled diagram > significance | (b(i)) explain: definition/context > points in order > small example > short close | (b(ii)) explain: definition/context > points in order > small example > short close | (c(i)) enumerate: list the items in order > one line each > no commentary | (c(ii)) describe: define > structure or process in order > labelled diagram > significance Full marks: Comprehensive, accurate, and well-structured answers with all required details and mechanisms.

  • Parts (fundus, body, isthmus, cervix), size, anteverted–anteflexed position, layers
  • Supports: pelvic floor (levator ani), cardinal (Mackenrodt), uterosacral, pubocervical ligaments; broad and round ligaments as secondary
  • Relations: bladder/vesicouterine pouch, rectum/pouch of Douglas, broad ligament, uterine artery crossing ureter
  • Blood (uterine and ovarian arteries; arcuate, radial, spiral) and lymph (para-aortic, superficial inguinal via round ligament, iliac, sacral); applied — prolapse, ureter injury in hysterectomy, fibroids, carcinoma spread
  • 30S inhibitors: aminoglycosides (misreading), tetracyclines (block aminoacyl-tRNA binding)
  • 50S inhibitors: chloramphenicol (peptidyl transferase), macrolides (translocation), linezolid (initiation complex)
  • Eukaryotic: cycloheximide (60S translocation), diphtheria toxin (ADP-ribosylates eEF-2), ricin/shiga toxin (28S rRNA depurination)
  • Puromycin in both (premature chain termination)
  • Definition: catalytic RNA
  • Examples: RNase P, self-splicing introns, spliceosomal snRNA, peptidyl transferase
  • 23S (prokaryotes)/28S (eukaryotes) rRNA as peptidyl transferase forming peptide bonds
  • Brief mechanism in the ribosomal large subunit
  • GH deficiency: proportionate, normal intelligence, delayed bone age, cherubic face
  • Hypothyroidism (cretinism): disproportionate, mental retardation, coarse features
  • Glucocorticoid excess, Laron syndrome (GH resistance, low IGF-1)
  • Precocious puberty/sex-steroid excess: early epiphyseal fusion; others (diabetes, pseudohypoparathyroidism)
  • Oogonia multiply in fetal ovary; primary oocytes enter meiosis I and arrest in prophase I (diplotene)
  • At puberty, cyclic completion of meiosis I before ovulation → secondary oocyte + first polar body
  • Arrest in metaphase II; completion only on fertilisation → second polar body
  • Follicular development stages
Q4
50M describe Facial nerve, Inguinal hernia, Renal clearance, RFLP, Anaemia, Eosinophils, Platelets

Describe the facial nerve under the following headings: 1. Functional columns and nuclei of origin 2. Course and branches 3. Bell's palsy Differentiate between indirect and direct inguinal hernia. Define renal clearance. What key features should be present in a compound for it to be considered as a 'gold standard' for measurement of renal clearance? Explain why urea is not considered as a 'gold standard' for this. Briefly describe the role of Restriction Fragment Length Polymorphism (RFLP) in DNA fingerprinting. Give the physiological basis of anaemia in kidney and liver disease. Describe the role of eosinophils in control of allergy reactions. Describe the role of platelets in haemostasis.

हिंदी में पढ़ें

आनन तंत्रिका का वर्णन निम्नलिखित शीर्षकों के अंतर्गत कीजिए : 1. क्रियात्मक स्तंभ तथा उद्गम के केंद्रक 2. मार्ग एवं शाखाएं 3. बेल पाल्सी तिर्यक वंक्षण हर्निया तथा ऋजु वंक्षण हर्निया के बीच भेद बताइए। वृक्क उत्सर्जन की परिभाषा दीजिए। किसी यौगिक में ऐसे कौन-कौन से मुख्य गुण विद्यमान होने चाहिए जिससे कि वह वृक्क उत्सर्जन मापन का 'स्वर्ण मानक' माना जा सके? समझाइए कि क्यों यूरिया, वृक्क उत्सर्जन मापन का 'स्वर्ण मानक' नहीं माना जाता। डी० एन० ए० अंगुलि छाप (फिंगरप्रिंटिंग) में प्रतिबंध खंड दैर्घ्य बहुरूपता (आर० एफ० एल० पी०) की भूमिका का संक्षेप में वर्णन कीजिए। वृक्क रोग तथा यकृत रोग में होने वाली अरक्तता का शरीर-क्रियात्मक आधार बताइए। प्रत्यूर्जता प्रतिक्रियाओं के नियंत्रण में इओसिनोफिल्स की भूमिका का वर्णन कीजिए। रक्तस्तम्भन में बिम्बाणुओं की भूमिका का वर्णन कीजिए।

Answer approach & key points

Framework: Medical Science, Paper 1. (a(i)) describe: define > structure or process in order > labelled diagram > significance | (a(ii)) compare: paired headings or point-wise contrast > key differences > significance > conclusion | (b(i)) define: precise definition > the distinguishing feature > one example | (b(ii)) describe: define > structure or process in order > labelled diagram > significance | (c(i)) explain: definition/context > points in order > small example > short close | (c(ii)) describe: define > structure or process in order > labelled diagram > significance | (c(iii)) describe: define > structure or process in order > labelled diagram > significance Full marks: Precise anatomical/physiological terminology, clear differentiation, and correct application of clinical concepts.

  • Components SVE (motor nucleus), GVE (superior salivatory/lacrimatory), SVA (nucleus tractus solitarius), GSA (spinal trigeminal)
  • Intracranial, intratemporal (meatal, labyrinthine, geniculate, tympanic, mastoid segments) and extracranial course; exits stylomastoid foramen
  • Branches: greater petrosal, nerve to stapedius, chorda tympani; posterior auricular, digastric, stylohyoid; five terminal branches in parotid
  • Bell's palsy: idiopathic LMN palsy — whole half of face including forehead, loss of taste, hyperacusis, Bell's phenomenon; steroids, eye care
  • Indirect: through deep ring, lateral to inferior epigastric vessels, within the cord coverings, can reach scrotum
  • Direct: through Hesselbach's triangle, medial to inferior epigastric vessels, outside the cord, rarely scrotal
  • Aetiology/age: indirect congenital (patent processus vaginalis), direct acquired/elderly
  • Clinical tests: deep ring occlusion, Zieman's test; strangulation risk higher in indirect
  • C = UV/P definition
  • Ideal marker: freely filtered, not reabsorbed or secreted, not metabolised, non-toxic, not protein-bound, easy to measure
  • Inulin as gold standard; creatinine as practical (slight secretion)
  • Urea: partly reabsorbed (varies with urine flow), so underestimates GFR
  • Restriction digestion of DNA; polymorphic fragment lengths (VNTR-based)
  • Electrophoresis, Southern blotting, probe hybridisation
  • Individual-specific banding pattern
  • Applications: forensics, paternity, genetic mapping; replaced by STR-PCR
  • CKD: erythropoietin deficiency (main), iron deficiency, uraemic marrow suppression, shortened RBC life, blood loss
  • Hepcidin excess in CKD inflammation
  • Liver disease: bleeding (varices, coagulopathy), hypersplenism, folate deficiency/alcohol, haemolysis (spur cells), macrocytosis
  • Normocytic normochromic pattern in CKD
  • Recruitment by IL-5, eotaxin
  • Granule contents: MBP, ECP, EPO, EDN
  • Modulating role: histaminase, arylsulfatase (degrades leukotrienes), inhibition of mast-cell degranulation
  • Also pro-inflammatory tissue damage in asthma
  • Adhesion via vWF–GPIb to exposed collagen
  • Activation and release (ADP, TXA₂, serotonin); shape change
  • Aggregation via GPIIb/IIIa–fibrinogen; platelet plug
  • Procoagulant surface (phosphatidylserine) and clot retraction; vasoconstriction

B

Q5
50M Compulsory discuss Pharmacology and Pathology - Antivirals, Chemotherapy, Hypersensitivity, Cancer, Diabetes complications, Injury

Discuss the antiviral spectrum and therapeutic uses of acyclovir. Doxorubicin is an antibiotic. Enumerate its role in cancer chemotherapy and its adverse effects. What is hypersensitivity? Enumerate different hypersensitivity reactions along with examples. Define type I hypersensitivity reaction and write its role in health and disease. Define cancer. Describe in detail the effects of cancer-related genes on cell growth. A 50-year-old male presented with a history of chest pain, polyuria and polydipsia since last 5 years. Investigations showed HbA1c level of 12%, cardiac enzymes were normal, while urinalysis showed proteinuria. (i) What is the most likely diagnosis? (ii) Describe the microscopic findings. (iii) What is the pathogenesis? Define injury. Discuss the microscopic and histochemical methods which can determine the age of injury.

हिंदी में पढ़ें

एसाइक्लोविर के प्रतिविषाणु स्पेक्ट्रम तथा चिकित्सार्थ उपयोगिताओं की व्याख्या कीजिए। डॉक्सोरुबिसिन एक ऐंटिबायोटिक है। कैंसर कीमोथेरेपी में उसकी भूमिका तथा उसके प्रतिकूल प्रभाव गिनाइए। अतिप्रतिक्रिया का क्या अर्थ है? विभिन्न अतिप्रतिक्रिया प्रतिक्रियाओं को उदाहरण सहित गिनाइए। टाइप I अतिप्रतिक्रिया प्रतिक्रिया को परिभाषित कीजिए तथा आरोग्य एवं रोग में उसकी भूमिका को उद्घिष्ट कीजिए। कैंसर को परिभाषित कीजिए। कोशिकीय वृद्धि पर कैंसर-संबंधी जीनों के प्रभावों का विस्तार से वर्णन कीजिए। एक 50-वर्षीय पुरुष, जिसे विगत 5 वर्षों से सीने में दर्द, बहुमूत्रता तथा अतिपिपासा के लक्षण हैं, अस्पताल में पहुँचता है। जाँच करने पर उसका HbA1c का स्तर 12% है, हृदय एन्जाइमों का स्तर सामान्य है और मूत्रविश्लेषण करने पर उसमें प्रोटीन है। (i) सर्वाधिक संभावित निदान क्या है? (ii) उसकी सूक्ष्मदर्शीय विशेषताओं का वर्णन कीजिए। (iii) उसका विकृतिजनन कैसे होता है? अभिघात को परिभाषित कीजिए। उन सूक्ष्मदर्शीय तथा उत्कर्षायन विधियों की व्याख्या कीजिए, जिनके द्वारा अभिघात की आयु निर्धारित की जा सकती है।

Answer approach & key points

Framework: Medical Science, Paper 1. (a(i)) discuss: intro > 3-4 dimensions > example > balanced close | (a(ii)) enumerate: list the items in order > one line each > no commentary | (b) enumerate: list the items in order > one line each > no commentary | (c) define: precise definition > the distinguishing feature > one example | (d(i)) explain: definition/context > points in order > small example > short close | (d(ii)) describe: define > structure or process in order > labelled diagram > significance | (d(iii)) explain: definition/context > points in order > small example > short close | (e) define: precise definition > the distinguishing feature > one example Full marks: Comprehensive, accurate, and well-structured answers with specific examples and mechanisms.

  • Mechanism: viral TK phosphorylation → triphosphate inhibits viral DNA polymerase, chain termination
  • Spectrum: HSV-1, HSV-2 > VZV; weak EBV; CMV resistant
  • Uses: mucocutaneous/genital herpes, HSV encephalitis (IV), neonatal herpes, varicella, zoster, keratitis, prophylaxis in immunocompromised
  • Resistance (TK-deficient) and adverse effects (crystalluria/nephrotoxicity)
  • Anthracycline: DNA intercalation, topoisomerase II inhibition, free radicals
  • Uses: breast cancer, lymphomas (ABVD, CHOP), leukaemias, sarcomas, other solid tumours
  • Cardiotoxicity (cumulative dose limit; dexrazoxane)
  • Myelosuppression, alopecia, mucositis, extravasation necrosis, red urine
  • Definition; Gell & Coombs types I–IV with examples
  • Type I mechanism: Th2/IgE sensitisation, FcεRI on mast cells, cross-linking, degranulation
  • Mediators and immediate vs late phase
  • Health: anti-helminth defence; disease: atopy, asthma, urticaria, anaphylaxis
  • Definition: clonal, autonomous, invasive, metastatic growth
  • Oncogenes (RAS, MYC, HER2) — gain of function
  • Tumour suppressors (RB, TP53) — loss of function, two-hit
  • Apoptosis genes (BCL-2) and DNA repair genes (BRCA, MMR); hallmarks
  • Poorly controlled diabetes mellitus (HbA1c 12%)
  • Diabetic nephropathy (proteinuria)
  • Chest pain with normal enzymes: angina/non-cardiac
  • Justification from history and tests
  • GBM thickening, mesangial expansion
  • Kimmelstiel–Wilson nodular glomerulosclerosis
  • Hyaline arteriolosclerosis (afferent and efferent), capsular drops, fibrin caps
  • Tubulointerstitial changes; papillary necrosis/pyelonephritis
  • Hyperglycaemia → AGEs
  • PKC activation, polyol pathway, oxidative stress
  • Hyperfiltration, intraglomerular hypertension (angiotensin II), podocyte injury
  • TGF-β-driven matrix; microalbuminuria → proteinuria → declining GFR
  • Legal definition (BNS 2023 s.2(14); formerly IPC s.44) and medical definition
  • Microscopic time-line: neutrophils, macrophages, granulation, haemosiderin (≈3 days), haematoidin (≈7 days), collagen
  • Enzyme histochemistry at wound margin: ATPase/esterase (1 h), aminopeptidase (2 h), acid phosphatase (4 h), alkaline phosphatase (8 h)
  • Special stains (Perls') and immunohistochemistry; ante-mortem vs post-mortem
Q6
50M describe Pathology and Microbiology - Breast cancer, Tuberculosis, Malaria, Helminthiasis, Candidiasis, Shigellosis

Describe the microscopic features of breast cancer. Enumerate any five major prognostic factors. Enumerate any five differences between primary tuberculosis and secondary tuberculosis. Explain why primaquine is used for radical cure of malaria. Explain why albendazole is termed as broad-spectrum oral antihelminthic. What is candidiasis? What are its different presentations and etiological causes? Give the laboratory diagnosis of a case of invasive candidiasis. What is shigellosis? What are its causative organisms and their modes of pathogenicity? Give the laboratory diagnosis of a case.

हिंदी में पढ़ें

स्तन कैंसर की सूक्ष्मदर्शीय विशेषताओं का वर्णन कीजिए। किन्हीं पाँच प्रमुख प्राज्ञान घटकों को लिखिए। प्राथमिक ट्यूबरक्यूलोसिस तथा द्वितीयक ट्यूबरक्यूलोसिस के बीच किन्हीं पाँच भिन्नताओं को गिनाइए। समझाइए कि क्यों प्राइमाक्विन मलेरिया से समूल रोगमुक्ति दिलाने में प्रयोग की जाती है। समझाइए कि क्यों एल्बेंडाजोल को विस्तृत-स्पेक्ट्रम मुख्य कृमिरोधी कहा जाता है। कैंडिडा-रणता क्या है? उसकी विभिन्न अभिव्यक्तियों तथा उसकी हेतुकी के कारण क्या हैं? आक्रामक कैंडिडा-रणता के मामले में प्रयोगशाला में कैसे निदान किया जाता है, बताइए। शिगेला-रणता क्या है? उसके कारक जीवाणु कौन-से हैं तथा उनकी रोगजनकता की पद्धति क्या है? प्रयोगशाला में शिगेला-रणता के मामले का कैसे निदान किया जाता है, बताइए।

Answer approach & key points

Framework: null. (a(i)) describe: define > structure or process in order > labelled diagram > significance | (a(ii)) enumerate: list the items in order > one line each > no commentary | (b(i)) explain: definition/context > points in order > small example > short close | (b(ii)) explain: definition/context > points in order > small example > short close | (c(i)) define: precise definition > the distinguishing feature > one example | (c(ii)) define: precise definition > the distinguishing feature > one example Full marks: Precise terminology, clear distinctions, specific examples, and correct lab tests.

  • DCIS (patterns incl. comedo) vs invasive carcinoma
  • Invasive NST: nests/cords/tubules, desmoplasia; Nottingham grading
  • Invasive lobular: single-file, E-cadherin loss; special types (mucinous, tubular, medullary pattern)
  • Prognostic factors: nodal status, size, grade/type, ER/PR/HER2 subtype, LVI/metastasis
  • Host/age: unsensitised child vs sensitised adult
  • Lesion: Ghon focus + hilar nodes (Ghon complex) vs apical Assmann/Simon foci
  • Caseation/cavitation: limited vs extensive with cavities
  • Spread and outcome: lymphohaematogenous/miliary, heals by calcification vs bronchogenic, smear-positive, progressive
  • Radical cure = eradication of hypnozoites of P. vivax/ovale
  • Blood schizonticides do not act on liver stages
  • Primaquine (8-aminoquinoline): tissue schizonticide/hypnozoitocide; 0.25 mg/kg/day × 14 days
  • Gametocytocidal for P. falciparum; G6PD haemolysis risk, avoid in pregnancy/infants
  • Benzimidazole; binds β-tubulin, inhibits microtubule polymerisation, glucose uptake
  • Ovicidal/larvicidal
  • Spectrum: nematodes (Ascaris, hookworm, Trichuris, Enterobius, Strongyloides), cestodes (neurocysticercosis, hydatid), some Giardia
  • Single 400 mg dose; mass deworming; sulfoxide metabolite penetrates tissues
  • Definition: opportunistic infection by Candida species
  • Presentations: mucocutaneous (thrush, vulvovaginitis, intertrigo, onychomycosis) and invasive (candidaemia, endocarditis, endophthalmitis, hepatosplenic)
  • Causes: species (C. albicans, non-albicans incl. C. auris) and predisposing factors (diabetes, antibiotics, neutropenia, catheters, HIV)
  • Diagnosis: specimens, KOH/Gram (budding yeast, pseudohyphae), culture (SDA), germ tube/CHROMagar/MALDI-TOF, β-D-glucan/mannan, AFST
  • Bacillary dysentery; low infectious dose; faeco-oral
  • Four serogroups (S. dysenteriae, flexneri, boydii, sonnei)
  • Pathogenesis: M-cell entry, macrophage apoptosis, basolateral invasion, T3SS/Ipa on virulence plasmid, cell-to-cell spread, Shiga toxin → HUS
  • Diagnosis: stool microscopy (pus cells), culture on MacConkey/XLD/DCA, biochemistry (non-motile, NLF), serogrouping, AST
Q7
50M discuss Forensic Medicine and Clinical Medicine - Hanging, Liver disease, Leukaemia, Pharmacology

Define death due to hanging. What are the probable causes of death in hanging? What are the findings in a case of judicial hanging? A 55-year-old female presented with haematemesis. On physical examination, she was afebrile and pale. No organomegaly was noted. Serological tests for hepatitis B were positive. 1. What is the most likely diagnosis? 2. Describe the microscopic findings. 3. What is the pathogenesis? Describe the clinical features and microscopic findings in acute lymphoblastic leukaemia. State the role of diuretics in the management of hypertension. Discuss how excess dose of paracetamol causes acute hepatocellular toxicity and how you will manage the condition. Elaborate the advantages and disadvantages of Sodium-Glucose Cotransporter-2 (SGLT-2) inhibitors in the management of diabetes mellitus.

हिंदी में पढ़ें

फाँसी से हुई मृत्यु को परिभाषित कीजिए। फाँसी में मृत्यु के संभावित कारण क्या-क्या होते हैं? न्यायिक फाँसी के मामले में क्या-क्या परिणाम दिखते हैं? एक 55-वर्षीय महिला को रक्तवमन हुआ है। शारीरिक जाँच करने पर उसे ज्वर नहीं है, पर उसका रंग फीका पड़ा हुआ है। उसके शरीर के किसी भी अंग में अतिवृद्धि नहीं पाई गई। सीरमी जाँच करने पर उसमें यकृत शोथ B की पुष्टि हुई है। 1. सर्वाधिक संभावित निदान क्या है? 2. उसकी सूक्ष्मदर्शीय विशेषताओं का वर्णन कीजिए। 3. उसका विकृतिजनन कैसे होता है? तीव्र लसीकाकोशिकाप्रसू श्वेतरक्तता की रोगलाक्षणिक विशेषताओं तथा सूक्ष्मदर्शीय विशेषताओं का वर्णन कीजिए। अतिरक्तदाब के प्रबंधन में मूत्रल औषधियों की भूमिका को उल्लिखित कीजिए। व्याख्या कीजिए कि पैरासिटामोल की अतिशय मात्रा कैसे तीव्र यकृत-कोशिकीय विषाक्तता उत्पन्न करती है तथा इस अवस्था का प्रबंधन कैसे किया जाना चाहिए। डायबिटीज मेलिटस के प्रबंधन में सोडियम-ग्लूकोज सहट्रांसपोर्टर-2 (SGLT-2) संदमकों के लाभ और हानियों को उल्लिखित कीजिए।

Answer approach & key points

Framework: Medical Science, Paper 1. (a(i)) define: precise definition > the distinguishing feature > one example | (a(ii)) describe: define > structure or process in order > labelled diagram > significance | (b(i)) explain: definition/context > points in order > small example > short close | (b(ii)) describe: define > structure or process in order > labelled diagram > significance | (c(i)) enumerate: list the items in order > one line each > no commentary | (c(ii)) discuss: intro > 3-4 dimensions > example > balanced close | (c(iii)) explain: definition/context > points in order > small example > short close Full marks: Precise definitions, correct mechanisms, and specific management protocols.

  • Definition: suspension by ligature with constricting force of body weight; complete/partial, typical/atypical
  • Asphyxia
  • Venous congestion and cerebral ischaemia (carotid/vertebral occlusion)
  • Reflex vagal inhibition; fracture-dislocation of C2–C3 in long drop; combination
  • Drop with knot under angle of jaw/chin; instantaneous death
  • Oblique, non-continuous ligature mark (inverted V)
  • Fracture-dislocation of C2 on C3 (hangman's fracture), cord/medulla injury
  • Face pale, minimal asphyxial signs, no salivary dribbling; soft-tissue injuries
  • Post-hepatitic (HBV) cirrhosis with portal hypertension and bleeding oesophageal varices
  • Microscopy: bridging fibrosis, regenerative nodules, ground-glass hepatocytes, interface hepatitis
  • Pathogenesis: CD8 T-cell immune injury, stellate cell activation (TGF-β, PDGF), fibrosis
  • Portal hypertension → portosystemic collaterals → variceal rupture (HVPG > 12 mmHg)
  • Commonest childhood cancer, peak 2–5 years
  • Marrow failure: anaemia, infection, bleeding; infiltration: bone pain, lymphadenopathy, HSM, mediastinal mass (T-ALL), CNS/testes
  • Blood/marrow: lymphoblasts ≥20%, high N:C, no Auer rods
  • Cytochemistry (MPO−, PAS block +) and immunophenotype (TdT+, CD19/CD10 or CD3/CD7)
  • Thiazide/thiazide-like as first-line (chlorthalidone, indapamide)
  • Mechanism: initial volume reduction, sustained fall in peripheral resistance
  • Indications: elderly, ISH, salt-sensitive, heart failure; combinations; spironolactone in resistant HT; loop in low eGFR
  • Adverse effects: hypokalaemia, hyponatraemia, hyperuricaemia, hyperglycaemia
  • Metabolism: glucuronidation/sulphation; CYP2E1 → NAPQI detoxified by glutathione
  • Overdose: glutathione depletion, NAPQI binding, zone-3 necrosis; risk factors
  • Management: charcoal, 4-h level on nomogram, N-acetylcysteine regimen
  • Supportive care; King's College criteria for transplant
  • Mechanism: block proximal tubular SGLT-2, glucosuria
  • Advantages: HbA1c fall, low hypoglycaemia risk, weight and BP reduction
  • Cardio-renal benefits (EMPA-REG, DAPA-HF, CREDENCE, DAPA-CKD)
  • Disadvantages: genital infections/UTI, volume depletion, euglycaemic DKA, Fournier's gangrene, reduced efficacy in low eGFR
Q8
50M describe Microbiology, Forensic Medicine and Pharmacology - Enteric fever, HIV, Virtual autopsy, Brain death, Infliximab, Natriuretic peptides

What is enteric fever? What are its causative agents? Give a detailed presentation of a case according to the time of the disease and the respective tests used for diagnosis. Draw a diagram of HIV virion depicting the various antigens and proteins. Give the serological pattern in an HIV infection according to the time of presentation. List the various diseases associated with AIDS. What is virtual autopsy? State its methodology. What are its merits? Define brain death. Describe its medicolegal importance. Discuss why infliximab is considered as an immunosuppressant. Mention its therapeutic uses. Describe briefly the pharmacological characteristics of natriuretic peptides and their clinical uses.

हिंदी में पढ़ें

आंत्र ज्वर क्या है? उसके कारक कौन-कौन से हैं? रोग की अवधि के अनुसार आंत्र ज्वर के मामले में किस समय पर क्या अभिव्यक्तियाँ होंगी और अलग-अलग समय पर कौन-कौन से टेस्ट निदान कर सकेंगे, इसका पूरा विवरण दीजिए। HIV विरियन का चित्र बनाइए, जिसमें विभिन्न प्रतिजनों तथा प्रोटीनों को चिह्नित किया गया हो। एक HIV संक्रमण के मामले में अभिव्यक्ति की समयावधि के अनुसार सीरमी पैटर्न क्या होगा, लिखिए। AIDS से संबद्ध विभिन्न रोगों के नाम गिनाइए। आभासी शव परीक्षण क्या है? उसकी विधि बताइए। उसकी अच्छाइयाँ क्या हैं? मस्तिष्कीय मृत्यु (ब्रेन डेथ) को परिभाषित कीजिए। उसके चिकित्सा-विधिक महत्व का वर्णन कीजिए। व्याख्या कीजिए कि इन्फ्लिक्सिमैब को इम्युनोसप्रेसेंट क्यों माना जाता है। उसके चिकित्सार्थ उपयोग को उल्लिखित कीजिए। अतिसोडियममुक्त पेप्टाइडों की फार्माकोलॉजिकल विशेषताएँ तथा उनकी रोगलाक्षणिक उपयोगिताओं का संक्षेप में वर्णन कीजिए।

Answer approach & key points

Framework: Medical Science, Paper 1. (a(i)) explain: definition/context > points in order > small example > short close | (a(ii)) describe: define > structure or process in order > labelled diagram > significance | (b(i)) explain: definition/context > points in order > small example > short close | (b(ii)) define: precise definition > the distinguishing feature > one example | (c(i)) discuss: intro > 3-4 dimensions > example > balanced close | (c(ii)) describe: define > structure or process in order > labelled diagram > significance Full marks: Comprehensive, accurate, and well-structured with all required elements and diagrams.

  • S. Typhi and S. Paratyphi A, B, C; faeco-oral
  • Week 1: step-ladder fever, relative bradycardia; blood culture (best early), bone marrow culture
  • Week 2: rose spots, splenomegaly, typhoid state; Widal rising titres; stool culture
  • Week 3–4: complications (haemorrhage, perforation); stool/urine culture; recovery or carrier state
  • Labelled virion: gp120, gp41, p17 matrix, p24 capsid, two ssRNA, RT, integrase, protease
  • Timeline: HIV RNA (~10 days), p24 (~2–3 weeks), antibodies (3–12 weeks; window period), 4th-gen assays
  • Confirmation per NACO three-test strategy; CD4 decline; AIDS at CD4 < 200 or defining illness
  • Associated diseases: TB, PCP, cryptococcal meningitis, toxoplasmosis, CMV, MAC, Kaposi, NHL, candidiasis, HIV encephalopathy, wasting
  • Definition: imaging-based (virtopsy) non-invasive/minimally invasive autopsy
  • Methods: PMCT, PMCT angiography, PMMR, 3D surface scanning, image-guided biopsy
  • Merits: preserves body, rapid, digital record, useful in mass disasters, religious objections, trauma/gas embolism
  • Limitations: histology, infections, cost; Indian experience (AIIMS)
  • Irreversible cessation of all brain including brainstem function
  • Criteria: coma, absent brainstem reflexes, apnoea test; exclusion of reversible causes; repeat testing
  • THOA 1994 (amended 2011): certification by a board of four doctors
  • Medicolegal: legal death, withdrawal of support, organ donation, time of death
  • Chimeric anti-TNF-α monoclonal antibody
  • Neutralises soluble/membrane TNF; reduces cytokine cascades, granuloma maintenance
  • Uses: Crohn's, UC, RA, ankylosing spondylitis, psoriasis/psoriatic arthritis
  • Risks: TB reactivation (screen), serious infections, infusion reactions, anti-drug antibodies
  • ANP (atria), BNP (ventricles), CNP (endothelium)
  • NPR-A/B → cGMP: natriuresis, vasodilatation, RAAS inhibition; degraded by neprilysin
  • Diagnostic use of BNP/NT-proBNP in heart failure
  • Therapeutic: nesiritide (recombinant BNP), sacubitril/valsartan (neprilysin inhibition)

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