List of causes of auto-amputation of fingers: 1. Diabetes 2. Raynaud's phenomenon 3. Buerger's disease 4. Scleroderma 5. Gangrene 6. Neurological disorder 7. Infection 8. Trauma 9. Vascular anomalies 10. Atherosclerosis 11. Vasculitis

Calcium is the "building material," but Vitamin D₃ helps the body absorb and use it. Without enough vitamin D, a significant portion of ingested calcium may simply pass through the gut unabsorbed

Sildenafil (Viagra) nitrates such as Nitroglycerin or Isosorbide Mononitrate Why is it so dangerous? Both drugs increase the nitric oxide (NO)–cGMP pathway, which relaxes vascular smooth muscle. 1. Nitrates -Release nitric oxide. -NO activates guanylate cyclase. -↑ cyclic GMP (cGMP). -Blood vessels dilate. 2.Sildenafil -Inhibits phosphodiesterase-5 (PDE-5). -PDE-5 normally breaks down cGMP. -Blocking PDE-5 causes cGMP to accumulate. When taken together: Nitrate makes more cGMP Sildenafil prevents cGMP breakdown Massive cGMP accumulation The result is profound systemic vasodilation: -Sudden drop in systemic vascular resistance -Marked hypotension -Reduced coronary perfusion pressure -Syncope -Myocardial ischemia/infarction -Cardiogenic collapse -Death in severe cases This is why a patient may suddenly faint or collapse shortly after standing or walking.

Methemoglobinemia. Why does the blood look chocolate brown? -In methemoglobinemia Iron in hemoglobin is oxidized from Fe²⁺ (ferrous) to Fe³⁺ (ferric). -Ferric hemoglobin (methemoglobin) cannot effectively carry oxygen. -The blood develops a characteristic chocolate-brown color that does not turn bright red on exposure to air. Common causes -Nitrates/nitrites -Benzocaine and other topical anesthetics -Dapsone -Aniline dyes -Certain local anesthetics (e.g., prilocaine) Treatment -Remove the offending agent -Methylene Blue (unless contraindicated, such as in significant G6PD deficiency)

Answer: C. Hydrochlorothiazide Why? In Nephrogenic Diabetes Insipidus, the kidneys are resistant to ADH, causing Massive polyuria,Polydipsia,Dilute urine Normally, a diuretic increases urine output. However, thiazides (eg hydrochlorothiazide) paradoxically decrease urine volume. Mechanism 1. Thiazide causes mild sodium and water loss. 2. This produces mild extracellular volume contraction. 3. The body compensates by increasing sodium and water reabsorption in the proximal tubule. 4. Less fluid reaches the collecting ducts. 5. Therefore, less water is lost in urine Net effect: ↓ urine volume by up to ~50% despite being a diuretic.

Because combine Paracetamol and Ibuprofen because they work through different mechanisms, giving better pain relief while reducing the risk of toxicity from pushing either drug to a high dose. Different mechanisms = additive analgesia 2.Paracetamol Primarily acts within the central nervous system. Reduces pain and fever. Has minimal anti-inflammatory effect. 2. Ibuprofen Inhibits COX enzymes. Reduces prostaglandin production. Provides pain relief, fever reduction, and anti-inflammatory effects. Because they target different pathways, the analgesic effect is often greater than using either drug alone. Increasing one drug has diminishing benefits Many drugs have a ceiling effect for analgesia. Increasing ibuprofen from a moderate dose to a very high dose may increase adverse effects more than pain relief Increasing paracetamol beyond recommended doses greatly increases the risk of liver toxicity without proportionally improving analgesia

In fulminant C. difficile colitis with ileus Oral drug may not reach the entire colon effectively Oral vancomycin is used for C. difficile because it is NOT absorbed. This is one of the few situations in medicine where a drug's poor absorption is actually its greatest advantage. Patients may receive: -Oral/NG vancomycin -Rectal vancomycin enemas -IV metronidazole The IV metronidazole helps because it reaches inflamed bowel tissues through the circulation.

The most important STD to rule out immediately is Lymphogranuloma Venereum Why? A patient with,Severe rectal pain,Rectal discharge History of receptive unprotected anal intercourse has proctitis, and LGV is a classic cause of severe, painful proctocolitis, especially in men who have sex with men. Differential diagnosis of STD-related proctitis 1. LGV (Chlamydia trachomatis L1–L3) – severe pain, discharge, bleeding, tenesmus. 2. Gonorrhea – purulent rectal discharge. 3. Herpes Simplex Infection – severe pain, ulcers. 4. Syphilis – anal chancre or secondary lesions. 5. Human Immunodeficiency Virus Infection – always test because of coinfection risk.

Answer: C. Yolk sac tumor Schiller-Duval bodies are characteristic of Yolk Sac Tumor (also called endodermal sinus tumor) A. Dysgerminoma-Fried egg cells, fibrous septae with lymphocytestm- LDH B. Granulosa cell tumor-Call-Exner bodies tm-Inhibin C. Yolk sac tumor- Schiller-Duval bodies tm-AFP D.Brenner tumor-Coffee-bean nuclei, transitional epithelium