Question 52 - Answer: (c) 1 and 3 only (HIV and Hepatitis C)

What Harrison's Says (Table 113-2)

Key Points

• HIV (item 1) - YES: Causes lymphoid malignancies (DLBCL and Burkitt's lymphoma) via immune dysregulation and failure to eliminate EBV-infected B cells.
• Hepatitis B (item 2) - NO: HBV is primarily associated with hepatocellular carcinoma, not lymphoid malignancies. It does NOT appear in Harrison's lymphoid malignancy table. (Some studies show a weak epidemiological link, but it is not an established, exam-standard association.)
• Hepatitis C (item 3) - YES: HCV is firmly linked to lymphoplasmacytic lymphoma (and Waldenström's macroglobulinemia) via chronic B-cell stimulation.

Correct Answer: (c) 1 and 3 only

• Harrison's Principles of Internal Medicine 22E, Table 113-2, p. 902

Q77 - Punctate bleeding spots on scraping a skin lesion

• Auspitz's sign = pinpoint bleeding points that appear when psoriatic scales are removed, due to traumatization of the dilated dermal capillaries beneath.
• Gottron's sign = skin changes over the knuckles (dermatomyositis).
• Barnett's sign = associated with systemic sclerosis.
• Punshi's sign = not a standard dermatology sign.

Q78 - Statements about CRPS

1. Type 1 CRPS may be precipitated by a traumatic event such as a fracture - TRUE. CRPS Type 1 follows a noxious event or immobilization (fracture being the classic trigger).
2. Type 1 CRPS is associated with peripheral nerve damage - FALSE. Type 1 has NO defined nerve injury. It is Type 2 (formerly causalgia) that is associated with a specific peripheral nerve injury.
3. Type 2 CRPS is associated with peripheral nerve damage - TRUE. Correct by definition.
4. Budapest criteria are used for diagnosis of CRPS - TRUE. The Budapest criteria are the internationally accepted diagnostic criteria for CRPS.

Q79 - Statements about DXA

1. DXA is used to measure bone mineral density - TRUE.
2. It works on the principle that calcium in bone attenuates passage of X-rays through tissue in proportion to the amount of mineral present - TRUE in principle (DXA uses differential attenuation of two X-ray energies by bone mineral).
3. Osteoporosis is defined when T-score lies between -1.0 and below +2.5 - FALSE/MISLEADING. The WHO definition of osteoporosis is T-score ≤ -2.5. A T-score between -1.0 and -2.5 is osteopenia, not osteoporosis. Statement 3 is incorrectly worded.
4. Co-existing conditions (e.g., aortic calcification or degenerative disc disease) can cause high bone mineral density even in the presence of osteoporosis - TRUE. Degenerative changes such as facet osteoarthritis and aortic calcification may artifactually raise the spine BMD on DXA.

Q80 - Classical DMARDs safe in pregnancy

1. Methotrexate - CONTRAINDICATED in pregnancy (teratogenic in animals and humans).
2. Sulfasalazine - SAFE (probably the safest DMARD in pregnancy).
3. Hydroxychloroquine - SAFE (probably the safest DMARD in pregnancy).
4. Leflunomide - CONTRAINDICATED in pregnancy (teratogenic).

Q81 - Finkelstein's sign/test

Q82 - First-rank symptoms of acute schizophrenia

• Statement 1 (Auditory hallucinations) = YES, first-rank
• Statement 2 (Broadcasting of thoughts) = YES, first-rank
• Statement 3 (Memory loss) = NO - memory loss is NOT a first-rank symptom (it is a cognitive feature, not psychotic)
• Statement 4 (Delusional perceptions) = YES, first-rank

Q83 - 44-year-old woman with OCD (contamination/hand-washing)

1. Diagnosis is made on the basis of history - TRUE. OCD is a clinical diagnosis based on history (obsessions + compulsions causing distress/impairment).
2. The disorder responds to antidepressant drugs - TRUE. SSRIs are first-line treatment for OCD.
3. Patients may be subjected to cognitive behaviour therapy - TRUE. CBT (specifically ERP - Exposure and Response Prevention) is first-line.
4. Admission to a psychiatry ward is mandatory - FALSE. Hospitalization is NOT mandatory for OCD; most cases are managed as outpatients.

Q84 - Point mutations: transition vs transversion

• Transition = replacement of a nucleotide by the same type: purine→purine (A↔G) OR pyrimidine→pyrimidine (C↔T)
• Transversion = replacement of a pyrimidine by a purine, or vice versa

1. Purine replaced by another purine = transition - TRUE ✓
2. Purine replaced by a pyrimidine = transversion - TRUE ✓
3. Pyrimidine replaced by another pyrimidine = transversion - FALSE. This is a transition, not a transversion.

Q85 - Flat, coloured lesion, <2 cm in diameter, not raised

• Macule = flat, circumscribed lesion, color different from surrounding skin, ≤2 cm in diameter - exactly matches the description.
• Patch = same as macule but >2 cm in diameter.
• Papule = small raised solid lesion, <0.5 cm - does NOT match (it is elevated).
• Nodule = larger raised firm lesion - does NOT match.

Q86 - Phenotypic changes NOT due to DNA sequence variation, but due to DNA/histone modifications

• Epigenetics = heritable phenotypic changes that occur without alteration of the underlying DNA sequence, caused by secondary modifications of DNA (e.g., methylation) or histones (e.g., acetylation, phosphorylation) in response to environmental influences. This is the exact definition given in the question.
• Pleiotropy = one gene affecting multiple traits.
• Co-dominance = both alleles expressed simultaneously.
• Epistasis = one gene masking the expression of another.

Q87 - 'Latrodectism' - local pain and sweating

• Latrodectism is the clinical syndrome caused by the bite of Latrodectus species (black widow spider). The venom is a potent peripheral neurotoxin. Clinical features include: sharp local pain, local redness and burning, followed by systemic effects - muscular cramps, diaphoresis (sweating), chest pain, nausea, intestinal spasms, and the classic "boardlike" abdominal tetanic cramps.
• King cobra causes neurotoxic envenomation (not latrodectism).
• Lonomia caterpillar causes hemorrhagic syndrome.
• Solenopsis ants cause allergic/anaphylactic reactions.

Q88 - Farmer with bronchorrhoea, sweating, salivation, bradycardia, miosis

1. The symptoms represent Anti-Cholinergic Syndrome - FALSE. These symptoms (bronchorrhoea, excessive salivation, bradycardia, miosis, sweating) are the hallmarks of CHOLINERGIC excess (muscarinic effects). Anticholinergic syndrome would cause the OPPOSITE: dry mouth, tachycardia, mydriasis, dry skin, urinary retention.
2. Activation of AChE enzyme is the underlying mechanism - FALSE. Organophosphates cause inhibition (not activation) of acetylcholinesterase, leading to accumulation of acetylcholine and cholinergic overactivity.
3. Intravenous Atropine should be given for treatment - TRUE. Atropine is the antidote - it blocks muscarinic receptors and reverses the cholinergic effects.

Q89 - Parasite-clinical manifestation pairs

1. Ancylostoma duodenale : Anemia - TRUE. Hookworms cause iron-deficiency anemia by blood-sucking.
2. Ascaris lumbricoides : Löffler Syndrome - TRUE. Larval migration through the lungs causes Löffler's syndrome (transient eosinophilic pneumonitis).
3. Loa loa : Katayama Fever - FALSE. Katayama fever is associated with Schistosoma (not Loa loa). Loa loa causes loiasis (conjunctival migration, Calabar swellings).
4. Trichinella spiralis : Myositis - TRUE. Trichinella larvae encyst in skeletal muscle, causing myositis, periorbital edema, and eosinophilia.

Q90 - Features present in Locked-in Syndrome

1. Cerebral cortex is intact - TRUE. Patients are fully conscious with intact cognition; it is NOT a disorder of consciousness.
2. Bilateral motor tracts are damaged - TRUE. The lesion destroys corticospinal tracts → quadriplegia and pseudobulbar palsy.
3. Some response to verbal stimuli may be present - TRUE. Patients can communicate using vertical eye movements and eyelid blinks (controlled rostral to the pons, which is intact).
4. Limb movement occurs in response to noxious stimuli - FALSE. In classic locked-in syndrome, there is profound quadriplegia with no voluntary limb movement. (Spinal triple-flexion reflex to noxious stimuli is a feature of brain death/spinal reflexes, not locked-in syndrome's defining features.)