Here are complete, exam-ready answers formatted for BDS 3rd Year General Medicine university pattern:
BDS 3rd Year General Medicine - University Examination Answers
Q1. Acute Myocardial Infarction (AMI) in a 70-Year-Old Patient on Dental Chair - Clinical Features and Management (10 Marks)
Introduction
Acute Myocardial Infarction (AMI) is defined as myocardial necrosis caused by prolonged ischemia, usually due to sudden occlusion of a coronary artery by a thrombus over an atherosclerotic plaque. In a 70-year-old patient on the dental chair, the risk is high due to pre-existing coronary artery disease, the stress of dental procedures (pain, anxiety, local anaesthetics with adrenaline), and the supine/semi-reclined position.
A. CLINICAL FEATURES
1. Symptoms
Chest Pain (Cardinal Feature)
- Sudden onset, severe, crushing, squeezing, or constricting pain
- Located in the centre of the chest (retrosternal), may radiate to:
- Left arm (most common)
- Jaw, neck, and teeth (of great dental relevance)
- Left shoulder, epigastrium, back
- Pain lasts >30 minutes (unlike angina which resolves in <15 min with rest or nitrates)
- NOT relieved by sublingual nitrates
Important Note for Dental Surgeons: Pain referred to the jaw and teeth can mimic toothache; any elderly patient complaining of sudden jaw/tooth pain with no apparent dental cause must be evaluated for cardiac origin.
Atypical Presentation in the Elderly (70-year-old)
- The elderly commonly present without chest pain (silent MI)
- May present with:
- Sudden breathlessness (dyspnoea)
- Confusion, disorientation, or loss of consciousness
- Profound weakness or fatigue
- Nausea, vomiting, epigastric discomfort
- Syncope or collapse
- Sudden onset of heart failure
2. Associated Symptoms
- Profuse sweating (diaphoresis) - cold, clammy skin
- Nausea and vomiting
- Severe anxiety, feeling of impending doom ("angor animi")
- Palpitations (due to arrhythmias)
- Breathlessness / dyspnoea
3. Signs on Examination
General:
- Patient is pale, ashen, cold and clammy
- Appears severely distressed and anxious
- Breathless
Vital Signs:
- Pulse: rapid and weak (tachycardia); may be irregular if arrhythmia present
- Blood pressure: may fall (cardiogenic shock) or initially elevated
- Temperature: mild fever may develop after 24-48 hours
- Respiratory rate: increased
Cardiovascular:
- Heart sounds may be faint
- S3 gallop (indicates LV failure)
- Soft systolic murmur (mitral regurgitation due to papillary muscle dysfunction)
- Pericardial friction rub (in transmural MI, day 2-3)
Signs of LV Failure:
- Fine basal crepitations in lungs
- Raised JVP (if RV involved)
- Central cyanosis in severe cases
B. IMMEDIATE MANAGEMENT IN THE DENTAL CHAIR
Act immediately - every minute counts ("Time is Muscle")
Step 1: Stop the Dental Procedure
- Stop all dental work immediately
- Remove instruments from the patient's mouth
- Keep the patient calm and reassured
Step 2: Position
- If conscious: Semi-reclined position (45 degrees) - do NOT lay flat (worsens breathlessness)
- If unconscious: Lay flat and begin BLS (Basic Life Support)
Step 3: Call for Help - ACTIVATE EMERGENCY SERVICES
- Call 108 / Emergency Medical Services immediately
- Inform them of suspected cardiac emergency
Step 4: Oxygen
- Administer high-flow oxygen 4-6 L/min by face mask
- Maintain SpO2 >94%
Step 5: Aspirin (MONA Protocol - used in dental settings)
- Aspirin 300 mg (chewed) - give immediately if not contraindicated
- Chewing is important (faster absorption than swallowing)
- Do not give if known aspirin allergy or active GI bleed
Step 6: Nitroglycerine (if available)
- Sublingual Glyceryl Trinitrate (GTN) 0.4 mg - if BP >90 mmHg systolic
- Repeat every 5 minutes x 3 doses if pain persists
Step 7: Monitor
- Monitor pulse, BP, and consciousness continuously
- Do NOT leave the patient alone
Step 8: Prepare for CPR
- If patient loses consciousness and has no pulse, begin:
- CPR: 30 chest compressions : 2 rescue breaths
- Use AED (Automated External Defibrillator) if available
Remember MONA: Morphine - Oxygen - Nitrates - Aspirin
C. MANAGEMENT IN HOSPITAL
A. Initial Assessment
- 12-Lead ECG - within 10 minutes of arrival
- Blood tests: Serum Troponin I/T (gold standard), CK-MB, CBC, RFT, serum electrolytes, blood glucose, lipid profile
- Chest X-ray
- Echocardiography
ECG Changes in AMI:
| Stage | ECG Change |
|---|
| Hyperacute | Tall peaked T waves |
| Acute (STEMI) | ST segment elevation (>1mm limb leads, >2mm chest leads) |
| Hours later | T wave inversion |
| Days later | Pathological Q waves (permanent - "tombstone") |
B. Reperfusion Therapy (Most Important)
1. Primary PCI (Percutaneous Coronary Intervention) - Gold Standard
- Balloon angioplasty + stenting of occluded artery
- Should be done within 90 minutes of first medical contact ("door to balloon time")
- Superior to thrombolysis
2. Thrombolysis (if PCI not available within 120 min)
- Streptokinase 1.5 million units IV over 60 min (older drug)
- Alteplase (tPA) - more clot specific, preferred
- Contraindicated in: recent surgery, active bleeding, stroke, uncontrolled hypertension
C. Medical Treatment
| Drug | Dose & Purpose |
|---|
| Aspirin | 300 mg loading, then 75-100 mg daily (antiplatelet) |
| Clopidogrel/Ticagrelor | P2Y12 inhibitor - dual antiplatelet therapy |
| Heparin (LMWH) | Anticoagulation - enoxaparin |
| Nitrates | IV nitroglycerin for pain and vasodilation |
| Oxygen | If SpO2 <94% |
| Morphine | 2-4 mg IV for pain relief |
| Beta-blockers | Metoprolol - reduce HR and O2 demand (if no bradycardia/hypotension) |
| ACE Inhibitors | Ramipril - reduce afterload, prevent remodelling |
| Statins | Atorvastatin 80 mg - plaque stabilization |
D. Management of Complications
- Arrhythmias: Lidocaine (VT/VF); atropine (bradycardia)
- Cardiogenic shock: Dopamine/dobutamine; IABP (intra-aortic balloon pump)
- Cardiac failure: Diuretics (frusemide IV)
- VF: Immediate DC defibrillation
Q2. Hyperthyroidism and Hypothyroidism - Clinical Features, Diagnosis, and Treatment of Hyperthyroidism (10 Marks)
HYPERTHYROIDISM (THYROTOXICOSIS)
Definition: A clinical syndrome caused by an excess of circulating thyroid hormones (T3 and T4).
Common Causes:
- Graves' disease (most common - autoimmune, TSI antibodies stimulate TSH receptor)
- Toxic multinodular goitre
- Toxic adenoma
- Thyroiditis (subacute)
- Excess iodine (Jod-Basedow effect)
A. CLINICAL FEATURES OF HYPERTHYROIDISM
Symptoms:
| System | Features |
|---|
| General | Weight loss despite increased appetite, heat intolerance, sweating, fatigue |
| Cardiovascular | Palpitations, tachycardia (even at rest), atrial fibrillation, hypertension |
| Neurological | Tremor of hands, anxiety, nervousness, irritability, emotional lability, insomnia |
| GI | Diarrhoea, increased bowel frequency, vomiting |
| Menstrual | Oligomenorrhoea, amenorrhoea |
| Musculoskeletal | Proximal myopathy, weakness, osteoporosis |
| Eyes | Exophthalmos/proptosis (specific to Graves'), lid lag, lid retraction, diplopia |
| Skin | Fine, smooth, moist skin; hair thinning, onycholysis (nail separation) |
Signs:
- Goitre (enlarged thyroid gland) - diffuse in Graves', nodular in MNG
- Bruit over thyroid (in Graves')
- Pretibial myxoedema (Graves' - skin thickening over shins)
- Thyroid acropachy (Graves' - clubbing + soft tissue swelling)
- Fine tremor on outstretched hands
- Warm, moist skin
- Tachycardia, hyperdynamic circulation
Graves' Disease Triad: Goitre + Exophthalmos + Pretibial myxoedema
HYPOTHYROIDISM
Definition: A clinical syndrome caused by insufficient production of thyroid hormones.
Common Causes:
- Hashimoto's thyroiditis (autoimmune - most common in adults)
- Iodine deficiency (most common worldwide)
- Post-thyroidectomy / post-radioiodine
- Drugs: amiodarone, lithium
- Pituitary/hypothalamic disease (secondary/tertiary)
- Congenital (Cretinism in neonates)
B. CLINICAL FEATURES OF HYPOTHYROIDISM
"SLOW" mnemonic:
| System | Features |
|---|
| General | Weight gain, cold intolerance, fatigue, lethargy, somnolence |
| Face/Skin | Puffy face, periorbital oedema, non-pitting oedema (myxoedema), dry coarse skin, pallor, yellowish tinge (carotenaemia) |
| Hair/Nails | Dry coarse hair, loss of outer third of eyebrows (pathognomonic), brittle nails |
| Cardiovascular | Bradycardia, cardiomegaly (myxoedema heart), pericardial effusion, hypertension, dyslipidaemia |
| Neurological | Slow mentation, memory loss, depression, psychosis (myxoedema madness), cerebellar ataxia, carpal tunnel syndrome, delayed relaxation of deep tendon reflexes (most important sign) |
| GI | Constipation, macroglossia |
| Reproductive | Menorrhagia, infertility, galactorrhoea |
| Voice | Hoarse, deep voice (myxoedema voice) |
| Musculoskeletal | Muscle cramps, proximal myopathy |
Myxoedema Coma (Severe): Hypothermia, coma, bradycardia, hyponatraemia - medical emergency
Cretinism (Congenital Hypothyroidism):
- Mental retardation, short stature, pot belly
- Protruding tongue, umbilical hernia
- Delayed milestones, deafness
C. DIAGNOSIS OF THYROID DISORDERS
| Investigation | Hyperthyroidism | Hypothyroidism |
|---|
| TSH (Thyroid Stimulating Hormone) | Decreased / Suppressed (most sensitive) | Elevated (earliest change) |
| Free T4 (FT4) | Elevated | Decreased |
| Free T3 (FT3) | Elevated | Decreased |
| TRAb/TSI | Positive in Graves' disease | - |
| Anti-TPO antibodies | May be elevated | Elevated in Hashimoto's |
| Radioactive Iodine Uptake (RAIU) | Increased (diffuse in Graves', patchy in MNG) | Decreased |
| Thyroid scan (Tc-99m) | Diffuse increased uptake (Graves') | Cold nodules |
| Ultrasound thyroid | Goitre, vascularity | Heterogeneous in Hashimoto's |
| CBC | Anaemia possible | Macrocytic anaemia |
| Lipids | Normal or low cholesterol | Elevated cholesterol/LDL |
| ECG | Tachycardia, AF | Bradycardia, low voltage, T wave flattening |
Key Diagnostic Rule:
- TSH is the single best screening test for thyroid dysfunction
- Low TSH = Hyperthyroidism; High TSH = Hypothyroidism
D. TREATMENT OF HYPERTHYROIDISM
1. Anti-thyroid Drugs (Thionamides) - First Line
- Carbimazole: Initial dose 10-20 mg every 12 hours; maintenance 5-10 mg/day
- Methimazole: Active metabolite of carbimazole; once-daily dosing possible
- Propylthiouracil (PTU): 100-200 mg every 6-8 hours; preferred in pregnancy (first trimester) and thyroid storm
- Mechanism: Inhibit thyroid peroxidase (TPO), reducing oxidation and organification of iodide; PTU also inhibits peripheral conversion of T4 to T3
- Course: 12-18 months for maximum remission (30-60%)
- Titration regimen: Gradually reduce dose as euthyroidism achieved
- Side effects: Agranulocytosis (monitor WBC if fever/sore throat), hepatotoxicity (PTU)
2. Beta-blockers (Symptomatic Relief)
- Propranolol 40-80 mg 3-4 times daily
- Reduces tachycardia, tremor, anxiety, sweating
- Does not reduce thyroid hormone levels
- Used until antithyroid drugs take effect (6-8 weeks)
3. Radioiodine Therapy (¹³¹I)
- Oral dose of radioactive iodine
- Destroys thyroid tissue permanently
- Preferred in: Adults >45 years, relapse after antithyroid drugs, toxic nodular goitre
- Contraindicated in: Pregnancy, breastfeeding, active Graves' ophthalmopathy
- Eventually leads to hypothyroidism (requires lifelong thyroxine replacement)
4. Surgery (Thyroidectomy)
- Total or near-total thyroidectomy
- Indicated in: Large goitre with compressive symptoms, suspected malignancy, failed medical/radioiodine therapy, pregnant women in 2nd trimester who fail drugs
- Must make patient euthyroid before surgery (with antithyroid drugs for 6-8 weeks + Lugol's iodine for 10 days pre-op)
5. Treatment of Graves' Ophthalmopathy
- Mild: Lubricating eye drops, dark glasses
- Moderate-severe: IV methylprednisolone pulses, teprotumumab (IGF-1R antibody)
- Severe (optic nerve compression): Orbital decompression surgery
6. Thyroid Storm Management (Emergency)
- PTU 600 mg orally, then 200-300 mg every 4 h
- Propranolol IV
- Lugol's iodine (after PTU) 1 hour later
- Hydrocortisone 100 mg IV 8-hourly
- IV fluids, paracetamol (not aspirin), ICU care
Q3. SHORT NOTES (10 x 5 = 50 Marks)
I. TENDER HEPATOMEGALY
Definition: Enlargement of the liver that is painful on palpation.
Causes:
- Infective:
- Amoebic liver abscess (most common cause of painful hepatomegaly in India)
- Pyogenic liver abscess
- Acute viral hepatitis (A, B, E)
- Infective mononucleosis
- Vascular:
- Congestive cardiac failure (CCF) - acute - hepatic congestion stretches Glisson's capsule
- Budd-Chiari syndrome
- Inflammatory:
- Cholangitis
- Acute alcoholic hepatitis
- Malignant:
- Rapid hepatic metastases (capsule stretch)
- Hepatocellular carcinoma
Clinical Features:
- Right hypochondrial pain, sometimes referred to right shoulder
- Liver enlarged, tender, smooth
- In CCF: Hepatojugular reflux positive; pulsatile liver (TR)
- In amoebic abscess: fever, leukocytosis, diarrhoea history
Investigation:
- LFTs, Serum amylase, SGOT/SGPT
- Ultrasound abdomen (abscess, vascular lesion)
- CT scan, Liver biopsy if needed
- Serology (amoebic abscess: indirect haemagglutination test)
Treatment:
- Directed at the cause
- Amoebic abscess: Metronidazole 800 mg TDS x 5-10 days
- CCF: Diuretics, ACE inhibitors, treat primary cause
II. ACUTE GASTRITIS
Definition: Acute inflammation of the gastric mucosa.
Aetiology:
- NSAIDs / Aspirin (most common - inhibit prostaglandin synthesis, reduce mucosal defence)
- Alcohol
- H. pylori infection (acute phase)
- Stress - critically ill patients (ICU), burns (Curling's ulcer), brain injury (Cushing's ulcer)
- Corticosteroids
- Bile reflux
- Radiation
Pathology:
- Erosions, petechial haemorrhages, mucosal oedema
- Loss of surface epithelium
- May progress to frank ulceration
Clinical Features:
- Epigastric pain, burning, discomfort
- Nausea, vomiting
- Anorexia
- Haematemesis or melaena (if bleeding erosion)
- Often asymptomatic (especially NSAID-induced)
Diagnosis:
- Upper GI endoscopy (OGD) - gold standard (erythema, erosions, haemorrhagic areas)
- Biopsy for H. pylori (rapid urease test, histology)
- H. pylori: Urea breath test, stool antigen test
Treatment:
- Stop the causative agent (NSAIDs, alcohol)
- Proton Pump Inhibitors (PPIs): Omeprazole 20-40 mg BD - reduce acid secretion (mainstay)
- H2 blockers: Ranitidine/Famotidine
- Antacids: Symptomatic relief
- Sucralfate / Misoprostol: Mucosal protection
- H. pylori eradication: Triple therapy - PPI + Amoxicillin + Clarithromycin x 14 days
- Stress ulcer prophylaxis in ICU: IV PPI or H2 blockers
III. BELL'S PALSY
Definition: Idiopathic unilateral lower motor neuron (LMN) facial nerve (VII nerve) palsy of acute onset.
Aetiology:
- Reactivation of Herpes Simplex Virus (HSV-1) in geniculate ganglion is the most accepted cause
- Results in oedema and entrapment of facial nerve in stylomastoid foramen
Clinical Features (ALL on the same side - ipsilateral):
- Sudden onset weakness/paralysis of all muscles of one side of face
- Inability to close eye (lagophthalmos) - corneal exposure risk
- Loss of forehead wrinkling (differentiates from UMN palsy - in UMN, forehead spared)
- Drooping of angle of mouth
- Bell's phenomenon: on attempting to close eye, eyeball rolls up (white sclera visible)
- Obliteration of nasolabial fold
- Food/liquid trapping in cheek
- Hyperacusis (if nerve to stapedius affected)
- Loss of taste on anterior 2/3 of tongue (chorda tympani affected)
- Decreased lacrimation (greater petrosal nerve affected)
Important for BDS: Dentists must be aware as dental procedures (mandibular block injection, parotid surgery) can injure facial nerve.
Investigations:
- Clinical diagnosis
- EMG/NCS: To assess nerve injury severity
- MRI: Rule out central cause, acoustic neuroma
Treatment:
- Prednisolone 60 mg/day for 5 days, then taper over 10 days (must start within 72 hours) - reduces inflammation
- Acyclovir 400 mg 5 times daily x 10 days (antiviral - for HSV)
- Eye care: Artificial tear drops, eye pad at night, glasses during day (prevent corneal exposure)
- Physiotherapy, facial exercises
- Most cases resolve within 3-6 months (85% full recovery)
IV. SCURVY
Definition: Vitamin C (Ascorbic Acid) deficiency disease.
Mechanism: Vitamin C is essential for hydroxylation of proline and lysine in collagen synthesis. Deficiency leads to defective collagen, resulting in capillary fragility and impaired wound healing.
At-risk Groups: Elderly, alcoholics, infants on unsupplemented formula, malnourished
Clinical Features:
(Extremely important for BDS - oral manifestations)
| System | Features |
|---|
| Gums (Dental importance) | Spongy, swollen, haemorrhagic gums; gums bleed easily on touch; gingival hypertrophy; loose teeth; pericoronitis |
| Skin | Perifollicular haemorrhages (pathognomonic), corkscrew/swan-neck hairs, easy bruising, ecchymoses |
| Musculoskeletal | Bleeding into joints (haemarthrosis), subperiosteal haemorrhage, painful swollen legs (especially children) |
| Wound healing | Poor wound healing |
| Anaemia | Microcytic or normocytic anaemia |
| Systemic | Fatigue, irritability, weakness, low-grade fever |
| Radiological (children) | Trummerfeld zone (zone of destruction), Pelkan spurs, Frankel line, Wimberger ring sign |
Diagnosis:
- Clinical (mainly)
- Serum/leucocyte vitamin C levels (low)
- X-ray (children): Ground glass appearance, cortical thinning
Treatment:
- Vitamin C 500-1000 mg/day orally for 1 month; maintenance 75-90 mg/day
- Dietary: Fresh fruits (amla, lemon, orange), green vegetables
- Resolution of symptoms usually within days to weeks
V. ANTITUBERCULAR TREATMENT (ATT)
First Line Drugs:
| Drug | Mechanism | Daily Dose | Side Effects |
|---|
| Isoniazid (H) | Inhibits mycolic acid synthesis | 5 mg/kg (max 300 mg) | Peripheral neuropathy (prevented by pyridoxine), hepatotoxicity, SLE-like syndrome |
| Rifampicin (R) | Inhibits RNA polymerase | 10 mg/kg (max 600 mg) | Hepatotoxicity, orange discolouration of urine/secretions, enzyme inducer (reduces efficacy of OCP, anticoagulants) |
| Pyrazinamide (Z) | Disrupts mycobacterial membrane potential | 25 mg/kg | Hyperuricaemia, gout, hepatotoxicity, arthralgia |
| Ethambutol (E) | Inhibits arabinosyl transferase | 15 mg/kg | Optic neuritis (dose-dependent, regular eye checks needed), colour blindness |
| Streptomycin (S) | Inhibits protein synthesis (30S) | 15 mg/kg | Ototoxicity (vestibular/auditory), nephrotoxicity, avoid in pregnancy |
Revised National TB Control Programme (RNTCP) / National TB Elimination Programme (NTEP) Regimen:
| Category | Patient Type | Intensive Phase | Continuation Phase |
|---|
| New cases | New PTB, EPTB | 2HRZE (2 months) | 4HR (4 months) |
| Previously treated | Failure, relapse | 2HRZES / 1HRZE | 5HRE |
| MDR-TB | Resistant to H + R | Individualised - bedaquiline, linezolid, clofazimine | |
Total Duration:
- Pulmonary TB: 6 months (2 + 4)
- TB meningitis, bone/joint TB, miliary TB: 9-12 months
- All treatment under DOTS (Directly Observed Treatment Short course)
Important for Dentists: Rifampicin causes orange staining of saliva; reduces efficacy of benzodiazepines used in dentistry.
VI. INSULIN
Types of Insulin:
| Type | Onset | Peak | Duration | Examples |
|---|
| Rapid-acting | 10-15 min | 1-2 h | 3-5 h | Lispro, Aspart, Glulisine |
| Short-acting (Regular) | 30-60 min | 2-4 h | 6-8 h | Regular/Soluble insulin |
| Intermediate | 2-4 h | 4-10 h | 12-18 h | NPH (Isophane) |
| Long-acting | 1-2 h | Peakless | 20-24 h | Glargine, Detemir |
| Ultra-long | 1-6 h | Peakless | >42 h | Degludec |
Mechanisms of Action:
- Binds to insulin receptor (tyrosine kinase receptor)
- Promotes glucose uptake in muscle and fat (GLUT-4)
- Inhibits gluconeogenesis and glycogenolysis in liver
- Promotes lipogenesis, inhibits lipolysis
- Anabolic: promotes protein synthesis
Indications:
- Type 1 Diabetes Mellitus (mandatory)
- Type 2 DM: When oral drugs fail, during illness/surgery/pregnancy, DKA, HHS
- Gestational diabetes mellitus (GDM)
- Diabetic ketoacidosis (DKA) - IV regular insulin
- Hyperkalaemia (drives K+ into cells)
Complications of Insulin Therapy:
- Hypoglycaemia (most common and dangerous)
- Lipodystrophy at injection sites
- Weight gain
- Oedema
- Local allergic reactions
- Insulin resistance
Dental Relevance:
- Diabetics on insulin are at risk of hypoglycaemia during dental procedures
- Never operate on a fasting diabetic on insulin
- Have glucose (juice/sugar) ready in dental clinic
VII. ANAPHYLACTIC REACTION
Definition: A severe, life-threatening systemic hypersensitivity reaction (Type I - IgE mediated) to an antigen, involving multiple organ systems.
Common Triggers in Dental Practice:
- Local anaesthetics (most common in dentistry - especially ester type)
- Penicillin / antibiotics
- NSAIDs (aspirin, ibuprofen)
- Latex gloves
- Contrast media
Pathophysiology:
- Antigen binds to IgE on mast cells and basophils
- Releases histamine, leukotrienes, prostaglandins, tryptase
- Massive vasodilation, increased capillary permeability, bronchoconstriction
Clinical Features (ABCDE):
| System | Features |
|---|
| Skin | Urticaria (hives), erythema, pruritus, angioedema, flushing |
| Airway | Laryngeal oedema (stridor), bronchoconstriction (wheeze), dyspnoea |
| Cardiovascular | Hypotension (shock), tachycardia, arrhythmia, collapse |
| GI | Nausea, vomiting, abdominal cramps, diarrhoea |
| CNS | Anxiety, dizziness, confusion, unconsciousness |
Signs: Hypotension, tachycardia, urticaria, angio-oedema, bronchospasm, cyanosis
IMMEDIATE MANAGEMENT:
- STOP the causative agent immediately
- Call for emergency help (108)
- Position: Lay patient flat with legs elevated (Trendelenburg); if breathing difficulty, sit up
- Adrenaline (Epinephrine) - FIRST AND MOST IMPORTANT DRUG:
- 0.5 mg (0.5 mL of 1:1000) IM into outer thigh (vastus lateralis)
- May repeat every 5-15 minutes
- Mechanism: alpha-1 vasoconstriction (raises BP), beta-2 bronchodilation, prevents further mediator release
- Oxygen: High flow 10-15 L/min
- IV access + IV fluids: Normal saline 500-1000 mL rapid infusion
- Antihistamine: Chlorpheniramine 10 mg IM/slow IV
- Corticosteroids: Hydrocortisone 200 mg IV (prevents late-phase reaction)
- Bronchodilator: Salbutamol inhaler / nebulizer if bronchospasm persists
- If cardiac arrest: CPR + ALS
Note: Adrenaline is the drug of choice - do NOT delay for antihistamines or steroids.
VIII. COMPLICATIONS OF ENTERIC FEVER (TYPHOID)
Causative organism: Salmonella typhi (Gram-negative bacillus)
Common Complications (occur in 3rd-4th week):
A. Intestinal Complications:
- Intestinal Perforation - Most serious; Peyer's patches in terminal ileum perforate; presents with acute abdomen, guarding, peritonitis, free gas under diaphragm on X-ray
- Intestinal Haemorrhage - Due to sloughing of Peyer's patches; melaena/haematochezia
- Paralytic Ileus
B. Hepatic:
4. Typhoid hepatitis - jaundice, hepatomegaly
5. Hepatic abscess (rare)
C. Cardiac:
6. Myocarditis - ECG changes, arrhythmias, heart failure
7. Pericarditis
D. Neurological:
8. Typhoid encephalopathy - altered consciousness
9. Meningitis
10. Peripheral neuropathy
E. Haematological:
11. Disseminated Intravascular Coagulation (DIC)
F. Respiratory:
12. Bronchitis, lobar pneumonia (typhoid pneumonia)
G. Urological:
13. Typhoid nephritis, UTI
H. Other:
14. Relapse (in ~10% despite treatment)
15. Chronic carrier state (Salmonella persists in gallbladder) - especially women with gallstones
Treatment of typhoid: Ceftriaxone 2g/day IV x 10-14 days (drug of choice currently); Ciprofloxacin if sensitive; Azithromycin for uncomplicated cases.
IX. NEPHROTIC SYNDROME
Definition: A clinical syndrome characterised by the tetrad:
- Heavy proteinuria (>3.5 g/day in adults; >40 mg/m²/hr in children)
- Hypoalbuminaemia (<3.5 g/dL)
- Generalised oedema (anasarca)
- Hyperlipidaemia and lipiduria
Causes:
- Primary (Idiopathic): Minimal Change Disease (MCD - most common in children), FSGS, Membranous nephropathy (most common in adults), Membranoproliferative GN
- Secondary: Diabetes mellitus (diabetic nephropathy), SLE (lupus nephritis), Amyloidosis, Malaria, HIV, drugs (gold, penicillamine)
Pathophysiology:
- Loss of negative charge on glomerular basement membrane (GBM) and/or structural damage
- Allows proteins (mainly albumin) to pass into urine
- Low albumin → low oncotic pressure → oedema
- Liver compensates by increasing VLDL production → hyperlipidaemia
Clinical Features:
- Oedema: Periorbital (early morning, most characteristic), dependent oedema, ascites, pleural effusion, scrotal/labial oedema
- Frothy urine (lipiduria, proteinuria)
- Pallor
- Anorexia, fatigue
- Possible hypertension (especially in secondary forms)
Complications:
- Infections (bacterial - Streptococcus pneumoniae, peritonitis) - due to loss of immunoglobulins
- Thromboembolism (renal vein thrombosis, DVT, PE) - loss of antithrombin III, protein C and S
- Hyperlipidaemia → accelerated atherosclerosis
- AKI
- Protein malnutrition, vitamin D deficiency, anaemia
Investigations:
- Urine: 24-hour protein, urine protein:creatinine ratio, lipid casts
- Serum albumin (low), serum cholesterol (high), TG (high)
- Serum creatinine and urea
- Renal biopsy (gold standard for definitive diagnosis - except typical MCD in children)
- Complement levels (C3, C4 - low in MPGN, SLE)
- ANA, anti-dsDNA (SLE), HBsAg, HCV, blood glucose
Treatment:
- Specific: Based on histology - Steroids (MCD: prednisolone 60 mg/day - excellent response), cyclophosphamide, cyclosporine
- Salt restriction, fluid restriction if severe oedema
- Diuretics: Frusemide (loop diuretic)
- ACE inhibitors/ARBs: Reduce proteinuria (e.g., ramipril, losartan)
- Statins: Manage hyperlipidaemia
- Anticoagulation if thromboembolism
- Antibiotics/prophylaxis for infections (penicillin V in children)
- Dietary protein intake: 0.8-1 g/kg/day of high-quality protein
X. HERPES ZOSTER (SHINGLES)
Definition: Reactivation of latent Varicella-Zoster Virus (VZV - a herpes virus) from the dorsal root ganglion or cranial nerve ganglia, producing a painful vesicular eruption in a dermatomal distribution.
Pathogenesis: VZV remains dormant in dorsal root ganglia after primary varicella (chickenpox). Reactivation occurs due to declining cell-mediated immunity (old age, immunosuppression, stress, HIV, malignancy).
Clinical Features:
(A) Prodromal Stage (2-4 days before rash):
- Burning, stabbing pain, hyperalgesia, itching along the dermatome
- Malaise, fever, headache
- No visible rash yet (often misdiagnosed)
(B) Eruptive Stage:
- Unilateral, dermatomal distribution (does NOT cross midline)
- Maculopapular rash → vesicles (clear fluid) → pustules → crusting
- Thoracic dermatomes most common (T3-T11)
- Intense pain (may persist as postherpetic neuralgia)
(C) Special Presentations (Dental/Medical Importance):
- Herpes Zoster Ophthalmicus (V1 - ophthalmic branch of trigeminal): Vesicles on forehead, tip of nose (Hutchinson's sign), risk of corneal ulceration and blindness
- Ramsay Hunt Syndrome (VII nerve - geniculate ganglion): Facial palsy + vesicles in external auditory canal/pinna + ipsilateral tinnitus, vertigo, deafness
- Oral Herpes Zoster (V2/V3 - maxillary/mandibular branch): Unilateral vesicles and ulcers on oral mucosa, palate, gingiva; extreme dental pain - relevant to dentists as it can mimic pulpitis or periapical abscess
- Zoster sine herpete: pain without rash
(D) Postherpetic Neuralgia:
- Pain persisting >3 months after rash heals
- Most common complication; seen in >50% patients above 60 years
- Burning, lancinating, allodynia (light touch causes pain)
Investigations:
- Mainly clinical diagnosis
- Tzanck smear: Multinucleated giant cells (also seen in HSV)
- PCR for VZV DNA (gold standard)
- VZV-specific IgM (acute), IgG (past infection)
Treatment:
- Antiviral drugs (must start within 72 hours of rash onset):
- Acyclovir 800 mg 5 times daily x 7-10 days (standard)
- Valacyclovir 1 g TDS x 7 days (better oral bioavailability, preferred)
- Famciclovir 500 mg TDS x 7 days
- Pain management:
- Paracetamol, NSAIDs (mild)
- Gabapentin / Pregabalin (neuropathic pain, postherpetic neuralgia)
- Amitriptyline (tricyclic antidepressant - for postherpetic neuralgia)
- Opioids (severe pain)
- Topical: Calamine lotion, antiviral cream
- Corticosteroids: Prednisolone may reduce acute pain and risk of postherpetic neuralgia (adjunct)
- Eye care: Topical acyclovir eye ointment, ophthalmology referral (Zoster ophthalmicus)
- Prevention: VZV vaccine (Shingrix - recombinant adjuvanted vaccine) - recommended for adults >50 years; 90% effective at preventing shingles
SUMMARY TABLE FOR QUICK REVISION
| Topic | Key Points to Remember |
|---|
| AMI in dental chair | MONA; Aspirin 300 mg chewed; call 108; semi-reclined position; AED |
| Hyperthyroidism | Graves' triad; Low TSH; Carbimazole/Methimazole; Propranolol for symptoms |
| Hypothyroidism | Delayed DTR; High TSH; Thyroxine replacement |
| Tender hepatomegaly | Amoebic abscess, CCF; U/S + serology |
| Acute gastritis | NSAIDs, H. pylori; PPIs; Triple therapy |
| Bell's palsy | LMN VII nerve; Steroids + Acyclovir within 72 hrs; Eye care |
| Scurvy | Vit C deficiency; Perifollicular haemorrhage; Spongy bleeding gums |
| ATT | HRZE x 6 months; DOTS; watch for hepatotoxicity |
| Insulin | Types by duration; IM adrenaline; Hypoglycaemia risk in dental chair |
| Anaphylaxis | Adrenaline 0.5 mg IM; Oxygen; IV fluids; Hydrocortisone |
| Typhoid complications | Intestinal perforation; Myocarditis; DIC; Carrier state |
| Nephrotic syndrome | 4 features; Renal biopsy; Steroids (MCD); ACEi/ARB |
| Herpes zoster | Dermatomal; Ramsay Hunt; Oral zoster; Acyclovir within 72 hrs; Postherpetic neuralgia |
All answers based on Harrison's Principles of Internal Medicine 22E, Goldman-Cecil Medicine, and standard BDS General Medicine curriculum. References: Harrison's, p.2150-2153 (AMI/ACS); Harrison's Thyroid section p.3079-3082 (Hyperthyroidism treatment); Washington Manual of Medical Therapeutics (Nephrotic Syndrome).