#!/usr/bin/env python3
"""
Dermatology OPD Cases – PDF Generator
Uses reportlab to create a well-formatted educational PDF.
"""

from reportlab.lib.pagesizes import A4
from reportlab.lib import colors
from reportlab.lib.units import mm, cm
from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle
from reportlab.platypus import (
    SimpleDocTemplate, Paragraph, Spacer, Table, TableStyle,
    HRFlowable, KeepTogether, PageBreak
)
from reportlab.lib.enums import TA_CENTER, TA_LEFT, TA_JUSTIFY
from reportlab.pdfbase import pdfmetrics
from reportlab.pdfbase.ttfonts import TTFont
import os

OUTPUT = "/home/daytona/workspace/dermatology-opd/Dermatology_OPD_Cases.pdf"

# ---------------------------------------------------------------------------
# CASE DATA
# ---------------------------------------------------------------------------
CASES = [
    {
        "no": 1,
        "title": "Acne Vulgaris (Mild)",
        "patient": "18-year-old male | Presenting complaint: Multiple comedones and a few papules on the face for 6 months",
        "diagnosis": "Mild Acne Vulgaris",
        "prescription": [
            ("Adapalene 0.1% gel", "Apply a pea-sized amount to entire face at night after washing", "12 weeks, review"),
            ("Benzoyl Peroxide 2.5% wash", "Use as face wash once daily in the morning", "12 weeks"),
            ("Clindamycin 1% lotion", "Apply to affected areas twice daily", "12 weeks (limit to prevent resistance)"),
            ("Sunscreen SPF 30+", "Apply every morning 20 min before sun exposure", "Ongoing"),
        ],
        "rationale": (
            "Adapalene (topical retinoid) normalises follicular keratinisation, prevents new comedone formation, "
            "and has anti-inflammatory properties. Benzoyl peroxide (BPO) is bactericidal against C. acnes and "
            "reduces antimicrobial resistance when combined with antibiotics. Topical clindamycin provides "
            "additional anti-inflammatory and antibacterial action. Sunscreen is mandatory because retinoids "
            "increase photosensitivity. (Dermatology 2-Vol Set 5e, Table 36.4)"
        ),
    },
    {
        "no": 2,
        "title": "Acne Vulgaris (Moderate-Severe)",
        "patient": "22-year-old female | Presenting complaint: Painful nodules, pustules, and scarring on face and back for 1 year; no response to topical agents",
        "diagnosis": "Moderate-to-Severe Nodular Acne Vulgaris",
        "prescription": [
            ("Isotretinoin 0.5 mg/kg/day orally", "Take with food (fatty meal enhances absorption)", "16–20 weeks; cumulative dose target 120–150 mg/kg"),
            ("Adapalene 0.1% + BPO 2.5% gel", "Apply to face at night", "Adjunct during treatment"),
            ("Pregnancy prevention counselling (iPLEDGE)", "Mandatory – two forms of contraception required", "Throughout course"),
            ("Moisturiser + SPF 30+", "Apply daily; isotretinoin causes dryness", "Throughout course"),
        ],
        "rationale": (
            "Isotretinoin (13-cis-retinoic acid) is the only drug that targets all four pathogenic factors of acne: "
            "sebum production, follicular keratinisation, C. acnes colonisation, and inflammation. It is indicated "
            "for nodular/cystic acne or acne unresponsive to conventional therapy. Teratogenicity mandates "
            "strict contraception. Lipid panel and LFTs should be monitored monthly. "
            "(Dermatology 2-Vol Set 5e, Table 36.4)"
        ),
    },
    {
        "no": 3,
        "title": "Atopic Dermatitis (Eczema)",
        "patient": "7-year-old boy | Presenting complaint: Intensely itchy, dry, scaly patches in antecubital and popliteal fossae; recurrent since age 2; family history of asthma",
        "diagnosis": "Atopic Dermatitis (Moderate)",
        "prescription": [
            ("Mometasone furoate 0.1% cream", "Apply thinly to inflamed areas once daily for 2 weeks (weekdays only – weekend holiday)", "2–4 weeks"),
            ("Tacrolimus 0.03% ointment", "Apply twice daily after steroid course; for maintenance and sensitive areas (face/folds)", "Ongoing as stepper"),
            ("Cetirizine syrup 5 mg (0.25 mg/kg)", "Once daily at night for itch", "4 weeks"),
            ("White soft paraffin / Emollient", "Apply liberally 2–3 times a day to entire body, especially after bath", "Lifelong"),
            ("Advice: lukewarm baths, cotton clothing, avoid triggers", "", ""),
        ],
        "rationale": (
            "Topical corticosteroids (TCS) are first-line anti-inflammatory therapy for atopic dermatitis flares. "
            "Mometasone is a mid-potency steroid suitable for children on the body. Tacrolimus (calcineurin inhibitor) "
            "is steroid-sparing and preferred for the face and flexures to avoid skin atrophy. Emollients are the "
            "cornerstone of AD management – they restore the skin barrier and reduce relapse frequency. "
            "Cetirizine helps with nocturnal itch and sleep. (Fitzpatrick's Dermatology, 9e; Andrews' Diseases of the Skin)"
        ),
    },
    {
        "no": 4,
        "title": "Psoriasis Vulgaris (Plaque Type)",
        "patient": "35-year-old male | Presenting complaint: Well-defined, silvery scaly plaques on elbows, knees, and scalp for 3 years; PASI 8",
        "diagnosis": "Chronic Plaque Psoriasis (Moderate)",
        "prescription": [
            ("Calcipotriol 0.005% + Betamethasone dipropionate 0.064% ointment", "Apply once daily to plaques for 4 weeks, then weekends only", "4 weeks active, then maintenance"),
            ("Coal tar shampoo 2%", "Apply to scalp, leave for 5 min, then rinse; use 3 times/week", "Ongoing"),
            ("Salicylic acid 6% ointment", "Apply to thick plaques 30 min before topical steroids to aid penetration", "Until scaling resolves"),
            ("Emollient / white soft paraffin", "Apply liberally twice daily to all areas", "Lifelong"),
            ("Referral for NB-UVB phototherapy if no response at 8 weeks", "", ""),
        ],
        "rationale": (
            "Calcipotriol (vitamin D analogue) reduces keratinocyte proliferation. Betamethasone dipropionate "
            "suppresses inflammation. The fixed-dose combination is more effective than either alone. "
            "Salicylic acid is a keratolytic that removes scale and facilitates penetration of other agents. "
            "Coal tar is anti-proliferative and anti-inflammatory. NB-UVB is first-line phototherapy for "
            "moderate-to-severe psoriasis. (Dermatology 2-Vol Set 5e, Table 8.19)"
        ),
    },
    {
        "no": 5,
        "title": "Tinea Corporis (Ringworm)",
        "patient": "28-year-old male | Presenting complaint: Annular, scaly, itchy lesion with central clearing on the forearm for 3 weeks; KOH mount positive for fungal hyphae",
        "diagnosis": "Tinea Corporis",
        "prescription": [
            ("Clotrimazole 1% cream", "Apply to lesion and 2 cm beyond margin twice daily", "4 weeks"),
            ("Terbinafine 250 mg tablet", "Once daily orally (if extensive or resistant)", "2 weeks"),
            ("Advice: keep area dry, avoid sharing towels/clothing", "", ""),
        ],
        "rationale": (
            "Clotrimazole is an imidazole antifungal that inhibits ergosterol synthesis in the fungal cell "
            "membrane, causing cell death. It is effective against dermatophytes (Trichophyton spp.). "
            "Terbinafine (allylamine class) is fungicidal by inhibiting squalene epoxidase; it is indicated for "
            "extensive, recurrent, or topical-resistant tinea. Treatment should continue 1 week beyond clinical "
            "clearance to prevent relapse. (Andrews' Diseases of the Skin; Medical Microbiology 9e)"
        ),
    },
    {
        "no": 6,
        "title": "Tinea Capitis",
        "patient": "9-year-old girl | Presenting complaint: Patchy hair loss with broken hairs, scaling, and mild cervical lymphadenopathy; KOH positive",
        "diagnosis": "Tinea Capitis (likely Trichophyton tonsurans – endothrix type)",
        "prescription": [
            ("Griseofulvin 10–20 mg/kg/day (microsize) orally", "Take with fatty meal once daily", "6–8 weeks"),
            ("Selenium sulfide 2.5% shampoo", "Apply twice weekly as sporicidal adjunct; leave 5 min before rinsing", "6–8 weeks (treat household contacts too)"),
            ("Ibuprofen 10 mg/kg if kerion present (inflammation)", "3 times daily with food for 1–2 weeks", "1–2 weeks"),
        ],
        "rationale": (
            "Tinea capitis requires systemic antifungal therapy because topical agents cannot penetrate the hair "
            "follicle sufficiently. Griseofulvin accumulates in keratin and is fungistatic. Terbinafine is an "
            "alternative with shorter courses. Selenium sulfide shampoo reduces fungal shedding and prevents "
            "household spread. Kerion (inflammatory mass) may require short-course corticosteroids to reduce "
            "scarring alopecia risk. (Red Book 2021; Andrews' Diseases of the Skin)"
        ),
    },
    {
        "no": 7,
        "title": "Tinea Pedis (Athlete's Foot)",
        "patient": "30-year-old male | Presenting complaint: Itchy, macerated, peeling skin between 3rd–4th toe spaces and sole, worse in summer; wears closed shoes all day",
        "diagnosis": "Tinea Pedis (Interdigital type)",
        "prescription": [
            ("Terbinafine 1% cream", "Apply to interdigital spaces twice daily", "1–2 weeks"),
            ("Miconazole 2% powder", "Dust inside shoes and socks daily", "Ongoing (prevents recurrence)"),
            ("Advice: dry feet thoroughly after bathing, cotton socks, open footwear", "", ""),
        ],
        "rationale": (
            "Terbinafine cream is fungicidal with a short treatment duration for tinea pedis. Antifungal powder "
            "in shoes reduces fungal load in the environment, which is the main source of re-infection. "
            "Moisture control is essential because Trichophyton rubrum thrives in warm, moist environments. "
            "(Andrews' Diseases of the Skin)"
        ),
    },
    {
        "no": 8,
        "title": "Scabies",
        "patient": "25-year-old male | Presenting complaint: Intense nocturnal itching, papules, and linear burrows on finger webs, wrists, genitalia, and axillae; family members also itching",
        "diagnosis": "Scabies",
        "prescription": [
            ("Permethrin 5% cream", "Apply from neck downward to entire body including under nails; wash off after 8–10 hours; repeat after 1 week", "2 applications"),
            ("Ivermectin 200 µg/kg orally (alternative/adjunct)", "Take with water on empty stomach; repeat after 2 weeks", "2 doses"),
            ("Hydroxyzine 25 mg at night", "For post-scabietic itch (itch may persist 2–4 weeks after cure)", "2–4 weeks"),
            ("Wash all bedding and clothing in hot water >60°C", "", "Once (decontamination)"),
            ("Treat ALL household contacts simultaneously", "", ""),
        ],
        "rationale": (
            "Permethrin 5% cream is the first-line scabicide – it is neurotoxic to Sarcoptes scabiei mites by "
            "disrupting sodium channel function. Two applications are required because permethrin is not ovicidal; "
            "the second dose kills mites that hatched from eggs surviving the first treatment. Ivermectin (oral) "
            "is added for crusted scabies or when topical therapy fails. Post-treatment itch is due to residual "
            "antigen, not re-infection. Treating household contacts prevents ping-pong re-infestation. "
            "(Red Book 2021; Dermatology 2-Vol Set 5e; Goldman-Cecil Medicine)"
        ),
    },
    {
        "no": 9,
        "title": "Urticaria (Acute)",
        "patient": "32-year-old female | Presenting complaint: Sudden onset of multiple, wheals all over the body after taking NSAIDs; resolving within 24 hours; no angioedema",
        "diagnosis": "Acute Urticaria (Drug-induced – NSAIDs)",
        "prescription": [
            ("Cetirizine 10 mg tablet", "Once daily", "1 week; extend if wheals recur"),
            ("Levocetirizine 5 mg (alternative)", "Once daily at night", "1 week"),
            ("Ranitidine 150 mg (H2 blocker – adjunct)", "Twice daily", "5–7 days (adds benefit when combined with H1 antihistamine)"),
            ("Prednisolone 40 mg orally (if severe wheals)", "Once daily in morning with food", "3–5 days (short tapering course)"),
            ("STOP/AVOID the offending NSAID; document allergy", "", ""),
        ],
        "rationale": (
            "Urticaria is mediated by mast cell degranulation releasing histamine, causing vasodilation and "
            "increased vascular permeability. Second-generation H1 antihistamines (cetirizine, levocetirizine) "
            "are first-line; they are non-sedating and long-acting. H2 blockers added to H1 antihistamines "
            "provide modest additional benefit. Short-course corticosteroids reduce the duration of acute severe "
            "urticaria but are NOT recommended for chronic urticaria. Drug avoidance is the definitive treatment "
            "for drug-induced urticaria. (Fitzpatrick's Dermatology, 9e; Dermatology 2-Vol Set 5e)"
        ),
    },
    {
        "no": 10,
        "title": "Chronic Spontaneous Urticaria",
        "patient": "40-year-old female | Presenting complaint: Daily wheals for 8 weeks, no identifiable trigger; thyroid antibodies positive; Dermatology Life Quality Index (DLQI) score 14",
        "diagnosis": "Chronic Spontaneous Urticaria (CSU) with possible autoimmune basis",
        "prescription": [
            ("Bilastine 20 mg tablet", "Once daily", "4 weeks; up-dose to 4× if inadequate response"),
            ("Fexofenadine 180 mg (alternative)", "Once daily", "4 weeks"),
            ("Omalizumab 300 mg subcutaneous injection", "Every 4 weeks (if refractory to high-dose antihistamine after 4 weeks)", "3–6 months"),
            ("Thyroid function tests + anti-TPO antibodies", "Monitor thyroid status", "Every 6 months"),
        ],
        "rationale": (
            "Second-generation H1 antihistamines are first-line for CSU. Up-dosing up to 4× the standard dose is "
            "recommended before stepping up. Omalizumab (anti-IgE monoclonal antibody) is licensed for CSU "
            "refractory to antihistamines; it blocks free IgE and reduces mast cell activation. Thyroid "
            "autoimmunity is commonly associated with CSU and should be managed if overt thyroid disease is present. "
            "(Fitzpatrick's Dermatology 9e; EAACI/GA2LEN/EDF guidelines)"
        ),
    },
    {
        "no": 11,
        "title": "Contact Dermatitis (Allergic)",
        "patient": "45-year-old female | Presenting complaint: Intensely itchy, vesicular, weeping rash on the neck and earlobes 48 hours after wearing new metal jewellery; patch test positive for nickel",
        "diagnosis": "Allergic Contact Dermatitis – Nickel allergy",
        "prescription": [
            ("Hydrocortisone 1% cream", "Apply twice daily to affected area", "1 week"),
            ("Betamethasone valerate 0.1% cream (if severe)", "Apply once daily to non-facial areas", "1–2 weeks then taper"),
            ("Chlorphenamine 4 mg tablet (sedating antihistamine)", "At night for severe itch", "5–7 days"),
            ("Emollient (aqueous cream / petroleum jelly)", "Apply frequently to soothe and protect", "Ongoing"),
            ("Advice: avoid all nickel-containing jewellery; use stainless steel or gold", "", ""),
        ],
        "rationale": (
            "Allergic contact dermatitis is a Type IV (delayed-type) hypersensitivity reaction. Topical "
            "corticosteroids are the mainstay to suppress the T-cell-mediated inflammatory response. "
            "Mild-potency steroids (hydrocortisone) for the face/neck; moderate-potency (betamethasone) for the "
            "body. Antihistamines help with itch but do not affect the underlying immune reaction. "
            "Allergen avoidance is the only definitive treatment – this must be emphasised to the patient. "
            "(Andrews' Diseases of the Skin; Fitzpatrick's Dermatology 9e)"
        ),
    },
    {
        "no": 12,
        "title": "Seborrhoeic Dermatitis",
        "patient": "29-year-old male | Presenting complaint: Greasy, yellowish scales on the scalp and nasolabial folds, with mild erythema; dandruff for 2 years, worsens in winter",
        "diagnosis": "Seborrhoeic Dermatitis",
        "prescription": [
            ("Ketoconazole 2% shampoo", "Apply to scalp, leave 3–5 min, rinse; use 3 times/week for 4 weeks then once/week maintenance", "4 weeks active, then maintenance"),
            ("Ketoconazole 2% cream", "Apply to nasolabial folds and eyebrows twice daily", "2–4 weeks"),
            ("Hydrocortisone 1% cream (for facial erythema)", "Apply once daily for up to 2 weeks", "Max 2 weeks – avoid prolonged use on face"),
            ("Zinc pyrithione shampoo", "Use alternating days with ketoconazole shampoo", "Ongoing maintenance"),
        ],
        "rationale": (
            "Seborrhoeic dermatitis is driven by Malassezia (Pityrosporum) yeasts, which colonise sebum-rich areas "
            "and induce an inflammatory response. Ketoconazole is an imidazole antifungal that targets Malassezia "
            "by inhibiting ergosterol synthesis; it is both antifungal and anti-inflammatory. Low-potency topical "
            "corticosteroids reduce erythema and itch. Zinc pyrithione has antifungal and antibacterial properties "
            "for maintenance. Prolonged facial corticosteroid use must be avoided (perioral dermatitis, rosacea risk). "
            "(Andrews' Diseases of the Skin)"
        ),
    },
    {
        "no": 13,
        "title": "Pityriasis Versicolor",
        "patient": "20-year-old male | Presenting complaint: Multiple hypopigmented and hyperpigmented scaly patches on chest, back, and upper arms; worse in summer; Wood's lamp shows yellow-green fluorescence",
        "diagnosis": "Pityriasis (Tinea) Versicolor",
        "prescription": [
            ("Ketoconazole 2% shampoo / Selenium sulfide 2.5% lotion", "Apply to affected areas, leave 10 min, rinse; daily for 2 weeks", "2 weeks"),
            ("Fluconazole 400 mg single oral dose (alternative)", "Single dose; may repeat in 1 week", "1–2 doses"),
            ("Itraconazole 200 mg daily", "For recurrent/extensive disease", "5–7 days"),
            ("Advice: pigment changes may take 1–3 months to fully resolve after cure", "", ""),
        ],
        "rationale": (
            "Pityriasis versicolor is caused by Malassezia furfur (and related species). Hypopigmentation results "
            "from azelaic acid produced by the yeast, which inhibits tyrosinase and reduces melanin synthesis in "
            "surrounding melanocytes. Selenium sulfide and ketoconazole shampoos are effective topical agents. "
            "Oral fluconazole or itraconazole is reserved for extensive disease or frequent relapse. The patient "
            "must understand that pigmentation normalises slowly even after fungal clearance. "
            "(Andrews' Diseases of the Skin; Medical Microbiology 9e)"
        ),
    },
    {
        "no": 14,
        "title": "Herpes Zoster (Shingles)",
        "patient": "60-year-old diabetic male | Presenting complaint: Painful, unilateral vesicular rash along T5 dermatome on the right side of chest; 2-day history; preceded by 3 days of burning pain",
        "diagnosis": "Herpes Zoster (VZV reactivation)",
        "prescription": [
            ("Acyclovir 800 mg tablet", "5 times daily (every 4 hours, omitting 1 night dose)", "7 days (start within 72 hours of rash onset)"),
            ("Valacyclovir 1 g (preferred – better bioavailability)", "3 times daily", "7 days"),
            ("Pregabalin 75 mg", "Twice daily (for neuropathic pain prevention and post-herpetic neuralgia)", "4–8 weeks"),
            ("Tramadol 50 mg", "Every 6–8 hours as needed for severe pain", "1–2 weeks"),
            ("Calamine lotion", "Apply to rash for soothing", "Until crusting"),
            ("Counselling: avoid contact with pregnant/immunocompromised individuals until all lesions crusted", "", ""),
        ],
        "rationale": (
            "Herpes zoster results from reactivation of latent varicella-zoster virus in dorsal root ganglia. "
            "Acyclovir/valacyclovir (nucleoside analogues) inhibit VZV DNA polymerase, reducing viral replication, "
            "rash severity, and the risk of post-herpetic neuralgia (PHN). Therapy is most effective if started "
            "within 72 hours of rash onset. Pregabalin is used for neuropathic pain both acutely and to prevent "
            "PHN. Diabetic patients have higher risk of complications and PHN. Zoster vaccine (recombinant subunit) "
            "is recommended for prevention in adults ≥50 years. (Harrison's Principles 22e)"
        ),
    },
    {
        "no": 15,
        "title": "Herpes Simplex (Labialis)",
        "patient": "24-year-old female | Presenting complaint: Recurrent painful vesicles on the lip with tingling prodrome; 5th episode this year; triggered by sun and stress",
        "diagnosis": "Recurrent Herpes Simplex Labialis (Orolabial HSV-1)",
        "prescription": [
            ("Acyclovir 5% cream", "Apply 5 times daily at first sign of tingling", "5 days (episodic therapy)"),
            ("Valacyclovir 500 mg orally", "Twice daily (for frequent recurrences >6/year – suppressive therapy)", "6–12 months"),
            ("Sunscreen lip balm SPF 30+", "Apply before sun exposure", "Ongoing (preventive)"),
        ],
        "rationale": (
            "Herpes simplex virus (HSV-1) causes recurrent orolabial herpes by periodically reactivating from "
            "trigeminal ganglia. Topical acyclovir reduces duration when applied at the prodromal stage. "
            "Oral valacyclovir given as suppressive therapy (daily) significantly reduces frequency of recurrences "
            "(≥6/year threshold for suppression). Sun exposure is a known trigger; UV protection prevents "
            "reactivation. (Harrison's Principles 22e)"
        ),
    },
    {
        "no": 16,
        "title": "Molluscum Contagiosum",
        "patient": "6-year-old girl | Presenting complaint: Multiple (>20) skin-coloured, dome-shaped, umbilicated papules on the trunk and axillae for 3 months; no immunodeficiency",
        "diagnosis": "Molluscum Contagiosum",
        "prescription": [
            ("Watchful waiting (observation)", "Reassure parents: self-limiting in immunocompetent children, usually resolves in 6–18 months", "First-line"),
            ("Imiquimod 5% cream (if cosmetically concerning or spreading)", "Apply 3 nights/week; leave overnight, wash off in morning", "Up to 16 weeks"),
            ("Cantharidin 0.7% solution (applied in clinic)", "Applied by physician to each lesion only; covered with occlusive tape for 4–6 hours", "Repeat every 3 weeks if needed"),
            ("Advice: avoid shared towels, do not scratch lesions", "", ""),
        ],
        "rationale": (
            "Molluscum contagiosum is caused by a poxvirus (Molluscipoxvirus) and is typically self-limiting in "
            "immunocompetent children. Active treatment is reserved for extensive, spreading lesions or social "
            "concerns. Imiquimod stimulates innate and adaptive immunity (TLR7/8 agonist) to clear the virus. "
            "Cantharidin is a blistering agent applied in clinic that mechanically destroys infected cells. "
            "Curettage is highly effective but requires local anaesthesia in children. (Andrews' Diseases of the Skin)"
        ),
    },
    {
        "no": 17,
        "title": "Warts (Verruca Vulgaris)",
        "patient": "15-year-old male | Presenting complaint: Hard, rough, cauliflower-like growths on the fingers and periungual area for 6 months; 5 lesions",
        "diagnosis": "Common Warts (Verruca Vulgaris) – HPV (types 2, 4)",
        "prescription": [
            ("Salicylic acid 15–26% solution (Duofilm/Occlusal)", "File wart surface, apply solution, cover with tape; daily application", "12 weeks (60% clearance rate)"),
            ("Liquid nitrogen cryotherapy (clinic)", "Applied as 2 freeze-thaw cycles every 2–3 weeks", "4–8 sessions"),
            ("Advice: do not bite fingers; keep warts covered at school", "", ""),
        ],
        "rationale": (
            "Warts are caused by human papillomavirus (HPV). Salicylic acid is keratolytic – it softens and breaks "
            "down the wart tissue and stimulates a local immune response. Cryotherapy with liquid nitrogen destroys "
            "wart tissue by forming intracellular ice crystals that rupture infected cells; it also triggers a "
            "local inflammatory immune response. Combination of both methods has higher success rates. Most warts "
            "spontaneously resolve within 2 years in immunocompetent individuals. "
            "(Andrews' Diseases of the Skin; Fitzpatrick's Dermatology 9e)"
        ),
    },
    {
        "no": 18,
        "title": "Rosacea",
        "patient": "38-year-old fair-skinned female | Presenting complaint: Persistent facial flushing, central facial erythema, papules and pustules on nose and cheeks; no comedones; triggered by alcohol and heat",
        "diagnosis": "Rosacea (Papulopustular subtype)",
        "prescription": [
            ("Metronidazole 0.75% gel", "Apply twice daily to affected areas after washing", "8–12 weeks (maintenance thereafter)"),
            ("Azelaic acid 15% gel", "Apply twice daily (alternative to metronidazole)", "12 weeks"),
            ("Doxycycline 40 mg (sub-antimicrobial dose – modified release)", "Once daily orally in the morning", "12 weeks (anti-inflammatory dose)"),
            ("Brimonidine 0.33% gel (for erythema/flushing)", "Apply once daily to affected areas", "As needed"),
            ("Advice: high SPF sun protection, avoid triggers (heat, alcohol, spicy food)", "", ""),
        ],
        "rationale": (
            "Rosacea pathophysiology involves neurovascular dysregulation, innate immune activation, and "
            "Demodex mite overgrowth. Metronidazole and azelaic acid reduce papulopustular lesions via "
            "anti-inflammatory and anti-microbial mechanisms against Demodex. Sub-antimicrobial doxycycline "
            "(40 mg MR) inhibits matrix metalloproteinases and reduces inflammation without selecting for "
            "antibiotic resistance. Brimonidine is an alpha-2 adrenergic agonist that reduces erythema by "
            "vasoconstriction. Strict sun protection is essential as UV triggers flares. "
            "(Fitzpatrick's Dermatology 9e; Andrews' Diseases of the Skin)"
        ),
    },
    {
        "no": 19,
        "title": "Vitiligo",
        "patient": "19-year-old female | Presenting complaint: Depigmented white patches on face, hands, and wrists; progressive for 1 year; no family history; Wood's lamp confirms depigmentation",
        "diagnosis": "Vitiligo (Non-segmental / Generalised)",
        "prescription": [
            ("Tacrolimus 0.1% ointment (face and neck)", "Apply twice daily to patches", "3–6 months; assess response"),
            ("Mometasone furoate 0.1% cream (body lesions)", "Apply once daily on weekdays (5-day-on/2-day-off schedule)", "3–4 months per course"),
            ("NB-UVB phototherapy (311 nm)", "2–3 sessions per week in dermatology unit", "6–12 months for significant repigmentation"),
            ("Vitamin D3 400 IU daily (adjunct)", "Oral supplementation", "Ongoing"),
            ("Counselling: camouflage cosmetics; avoid trauma to depigmented skin", "", ""),
        ],
        "rationale": (
            "Vitiligo results from autoimmune destruction of melanocytes in the epidermis. Topical calcineurin "
            "inhibitors (tacrolimus) and topical corticosteroids reduce the local autoimmune attack and allow "
            "melanocyte repopulation from follicular reservoirs. NB-UVB stimulates residual melanocytes to "
            "proliferate and migrate and also has immunomodulatory effects. Response is best in recently active "
            "patches on the face. Vitamin D deficiency is commonly associated with vitiligo. "
            "(Fitzpatrick's Dermatology 9e)"
        ),
    },
    {
        "no": 20,
        "title": "Melasma",
        "patient": "30-year-old pregnant female | Presenting complaint: Bilateral brown patches on the cheeks, forehead, and upper lip for 6 months; worsened during pregnancy and with sun exposure",
        "diagnosis": "Melasma (Chloasma Gravidarum)",
        "prescription": [
            ("Broad-spectrum SPF 50+ sunscreen", "Apply every 2 hours during sun exposure; re-apply after sweating", "Lifelong – most important intervention"),
            ("Azelaic acid 20% cream (safe in pregnancy)", "Apply twice daily", "Until delivery; continue postpartum"),
            ("Hydroquinone 4% cream (postpartum only)", "Apply twice daily to hyperpigmented areas at night", "3 months courses; avoid in pregnancy"),
            ("Triple combination cream: hydroquinone 4% + tretinoin 0.05% + fluocinolone 0.01% (Tri-Luma)", "Apply at night (postpartum, non-pregnant)", "8–24 weeks"),
            ("Physical sunscreen (zinc oxide/titanium dioxide) preferred", "Preferred over chemical UV filters in pregnancy", ""),
        ],
        "rationale": (
            "Melasma is caused by UV-induced upregulation of melanogenesis in genetically predisposed individuals; "
            "oestrogen and progesterone also stimulate melanocytes. Sun protection is the single most effective "
            "intervention and the cornerstone of management. Azelaic acid inhibits tyrosinase and is safe in "
            "pregnancy (Category B). Hydroquinone (tyrosinase inhibitor) is the gold standard for non-pregnant "
            "patients. The triple combination cream (hydroquinone + tretinoin + corticosteroid) produces faster "
            "and more complete depigmentation. (Fitzpatrick's Dermatology 9e)"
        ),
    },
    {
        "no": 21,
        "title": "Alopecia Areata",
        "patient": "25-year-old male | Presenting complaint: Sudden onset single circular patch of hair loss on scalp (5 cm diameter) for 2 months; no scarring; exclamation-mark hairs on dermoscopy",
        "diagnosis": "Alopecia Areata (Patchy type, <50% scalp involvement)",
        "prescription": [
            ("Intralesional triamcinolone acetonide 5 mg/mL", "Injected into scalp patch every 4–6 weeks (performed in clinic)", "3–6 sessions"),
            ("Mometasone furoate 0.1% scalp lotion", "Apply twice daily to patches", "3 months"),
            ("Minoxidil 5% solution or foam", "Apply twice daily to affected areas", "Minimum 6 months (promotes regrowth)"),
            ("Counselling: most cases spontaneously regrow within 1 year; discuss realistic expectations", "", ""),
        ],
        "rationale": (
            "Alopecia areata is an organ-specific autoimmune disease in which T-cells attack anagen hair follicles. "
            "Intralesional corticosteroids suppress the perifolicular inflammation and restore hair growth; "
            "triamcinolone 5 mg/mL is preferred for scalp (10 mg/mL for beard). Topical steroids and minoxidil "
            "are adjuncts to intralesional treatment. Minoxidil prolongs anagen phase and promotes regrowth via "
            "potassium channel opening. JAK inhibitors (tofacitinib, baricitinib) are emerging options for "
            "severe/refractory alopecia areata. (Fitzpatrick's Dermatology 9e)"
        ),
    },
    {
        "no": 22,
        "title": "Androgenetic Alopecia (Male Pattern Baldness)",
        "patient": "32-year-old male | Presenting complaint: Progressive bitemporal recession and crown thinning for 3 years; Norwood-Hamilton grade III vertex; no systemic disease",
        "diagnosis": "Male Androgenetic Alopecia (Norwood III-V)",
        "prescription": [
            ("Finasteride 1 mg tablet", "Once daily orally; take consistently at the same time", "Minimum 12 months to assess effect; continue long-term"),
            ("Minoxidil 5% topical solution", "Apply 1 mL twice daily to dry scalp", "Minimum 12 months; ongoing"),
            ("Ketoconazole 2% shampoo", "Twice weekly (reduces scalp inflammation/Malassezia)", "Ongoing adjunct"),
            ("Counselling: shedding may worsen in first 3 months (normal); results gradual; discontinuation = relapse", "", ""),
        ],
        "rationale": (
            "Androgenetic alopecia is driven by DHT (dihydrotestosterone) binding to androgen receptors in "
            "hair follicles, causing follicular miniaturisation. Finasteride inhibits 5-alpha-reductase type II, "
            "reducing scalp DHT by ~70%; it halts progression and can stimulate some regrowth. Minoxidil "
            "extends the anagen phase and increases follicle size by opening ATP-sensitive potassium channels "
            "and increasing VEGF. The combination of both agents has superior efficacy. PSA should be monitored "
            "and patients counselled about sexual side effects of finasteride. (Fitzpatrick's Dermatology 9e)"
        ),
    },
    {
        "no": 23,
        "title": "Onychomycosis (Nail Fungus)",
        "patient": "50-year-old diabetic female | Presenting complaint: Thickened, discoloured (yellow-brown), brittle toenails on both great toes for 1 year; KOH positive; nail plate scoring confirmed",
        "diagnosis": "Distal Subungual Onychomycosis (Trichophyton rubrum) – DLSO type",
        "prescription": [
            ("Terbinafine 250 mg tablet", "Once daily with food", "12 weeks for toenails, 6 weeks for fingernails"),
            ("Amorolfine 5% nail lacquer (adjunct)", "Apply to affected nails once weekly; file before application", "Duration of systemic treatment"),
            ("Urea 40% paste under occlusion", "Apply for 2 weeks before oral antifungal to soften and debulk thickened nail plate", "2 weeks pre-treatment"),
            ("Monitor LFTs at baseline and 4 weeks (terbinafine is hepatically metabolised)", "", ""),
        ],
        "rationale": (
            "Onychomycosis rarely responds to topical treatment alone because antifungals cannot adequately "
            "penetrate the nail plate. Oral terbinafine is fungicidal against dermatophytes (which cause 90% of "
            "cases) and accumulates in the nail plate at therapeutic concentrations. Amorolfine lacquer is a "
            "topical morpholine antifungal that adds localised activity and reduces relapse. Nail debulking with "
            "urea improves drug penetration. Diabetic patients need treatment due to risk of secondary bacterial "
            "infection. LFT monitoring is mandatory. (Andrews' Diseases of the Skin; Goldman-Cecil Medicine)"
        ),
    },
    {
        "no": 24,
        "title": "Pityriasis Rosea",
        "patient": "21-year-old male | Presenting complaint: 'Herald patch' followed 1–2 weeks later by multiple oval, salmon-coloured patches with 'collarette' scaling on the trunk; bilateral T2–L2 distribution; mild itch",
        "diagnosis": "Pityriasis Rosea",
        "prescription": [
            ("Cetirizine 10 mg", "Once daily at night for itch", "2–4 weeks (self-limiting condition)"),
            ("Emollient / calamine lotion", "Apply twice daily to soothe rash", "Until resolution"),
            ("Acyclovir 800 mg 5 times daily (if severe/early onset, <1 week)", "Oral; reduces severity and duration by ~50% if given early", "1 week (optional – evidence limited)"),
            ("Advice: reassure – rash resolves spontaneously in 6–8 weeks; avoid hot showers (can worsen rash)", "", ""),
        ],
        "rationale": (
            "Pityriasis rosea is associated with HHV-6 and HHV-7 reactivation. It is self-limiting and "
            "management is mainly symptomatic. Antihistamines reduce itch. Some evidence supports early "
            "acyclovir reducing duration of rash, likely by inhibiting HHV-6/7 replication. NB-UVB "
            "phototherapy can also be used for extensive or persistent cases. Patient education about the "
            "benign, self-limiting nature is essential to reduce anxiety. "
            "(Andrews' Diseases of the Skin; Fitzpatrick's Dermatology 9e)"
        ),
    },
    {
        "no": 25,
        "title": "Drug Rash (Maculopapular Drug Eruption)",
        "patient": "55-year-old female | Presenting complaint: Widespread symmetrical maculopapular rash starting 10 days after starting ampicillin for a tooth infection; mild itch; no mucosal involvement",
        "diagnosis": "Maculopapular Drug Eruption (Ampicillin exanthem)",
        "prescription": [
            ("STOP the offending drug (ampicillin) immediately", "", "Definitive management"),
            ("Chlorphenamine 4 mg tablet", "Every 6 hours for itch", "5–7 days"),
            ("Betamethasone valerate 0.1% cream", "Apply twice daily to rash on body", "1–2 weeks"),
            ("Prednisolone 30 mg orally (if extensive/severe)", "Once daily morning; taper over 7 days", "7–10 days"),
            ("Document allergy clearly in notes; advise patient to inform future prescribers", "", ""),
        ],
        "rationale": (
            "Maculopapular drug eruptions are the most common form of drug rash. Ampicillin rash occurs in "
            "~10% of patients and approaches 100% in patients with infectious mononucleosis (EBV). This is NOT "
            "a true allergy but a drug-virus interaction. Drug withdrawal is paramount. Topical corticosteroids "
            "and antihistamines are symptomatic. Any sign of mucosal involvement, blistering, or systemic "
            "symptoms warrants urgent reassessment for Stevens-Johnson Syndrome / TEN. "
            "(Andrews' Diseases of the Skin; Harrison's Principles 22e)"
        ),
    },
    {
        "no": 26,
        "title": "Erythema Multiforme (Minor)",
        "patient": "27-year-old male | Presenting complaint: Target lesions on palms and dorsum of hands appearing 10 days after herpes simplex labialis outbreak; no mucosal involvement",
        "diagnosis": "Erythema Multiforme Minor (HSV-associated)",
        "prescription": [
            ("Acyclovir 400 mg twice daily (suppressive dose)", "Once settled – to prevent future HSV outbreaks and thereby prevent EM recurrences", "6–12 months"),
            ("Cetirizine 10 mg at night", "Symptomatic relief of itch", "2–3 weeks"),
            ("Emollient / calamine lotion", "Apply to lesions for comfort", "Until resolution"),
            ("Reassure: self-limiting, resolves in 2–6 weeks", "", ""),
        ],
        "rationale": (
            "HSV is the trigger in the majority of recurrent EM minor cases. The mechanism involves HSV DNA "
            "deposition in the skin triggering a CD4+ T-cell-mediated immune response. Suppressive acyclovir "
            "is the most effective strategy to prevent recurrent HSV-associated EM – it reduces HSV shedding. "
            "Symptomatic treatment only is needed for the current episode. Severe or mucosal involvement "
            "suggests EM major or Stevens-Johnson Syndrome and requires urgent escalation. "
            "(Andrews' Diseases of the Skin)"
        ),
    },
    {
        "no": 27,
        "title": "Lichen Planus",
        "patient": "40-year-old male | Presenting complaint: Intensely itchy, violaceous, polygonal flat-topped papules on wrists and ankles; lacy white network on buccal mucosa; Wickham's striae visible",
        "diagnosis": "Lichen Planus (Cutaneous + Oral)",
        "prescription": [
            ("Betamethasone dipropionate 0.05% ointment", "Apply twice daily to skin lesions under occlusion", "4 weeks; taper"),
            ("Triamcinolone acetonide 0.1% oral paste (Orabase)", "Apply to oral mucosal lesions 2–3 times daily after meals", "4–8 weeks"),
            ("Hydroxyzine 25 mg at night", "Sedating antihistamine for severe itch / sleep disturbance", "As needed"),
            ("Acitretin 25 mg (for extensive/resistant cases)", "Once daily orally with fatty meal; avoid pregnancy (teratogen)", "3–6 months"),
            ("Liver function tests, Hep B & C serology (LP can be associated with HCV)", "", "Baseline"),
        ],
        "rationale": (
            "Lichen planus is a T-cell-mediated autoimmune condition targeting basal keratinocytes expressing "
            "altered antigens. Potent topical corticosteroids are first-line for skin lesions; they suppress "
            "the inflammatory CD8+ T-cell response. Oral mucosal lesions require topical corticosteroid "
            "preparations in adhesive base. Acitretin (retinoid) modulates keratinocyte differentiation and "
            "immune response in resistant cases. HCV screening is important given the well-established "
            "association between hepatitis C and lichen planus. (Andrews' Diseases of the Skin; Fitzpatrick's 9e)"
        ),
    },
    {
        "no": 28,
        "title": "Hyperhidrosis (Axillary)",
        "patient": "23-year-old female | Presenting complaint: Excessive sweating from both axillae, embarrassing, present since teenage years; wets through clothing; no secondary cause identified",
        "diagnosis": "Primary Focal Axillary Hyperhidrosis",
        "prescription": [
            ("Aluminium chloride hexahydrate 20% solution (Driclor)", "Apply to dry axillae at night; wash off in morning; use every night for 1 week, then as needed", "Ongoing"),
            ("Botulinum toxin A 50–100 U per axilla (clinic procedure)", "Injected intradermally into axillae; repeat every 6–12 months", "Highly effective for 6–12 months"),
            ("Oxybutynin 5 mg (anticholinergic – if topical insufficient)", "Once daily; up-titrate to 7.5–10 mg if needed", "Trial of 4 weeks"),
            ("Advice: fragrance-free antiperspirant vs deodorant distinction", "", ""),
        ],
        "rationale": (
            "Hyperhidrosis results from overactivity of eccrine sweat glands under sympathetic cholinergic "
            "stimulation. Aluminium chloride hexahydrate precipitates within sweat ducts, physically blocking "
            "them – it is the most cost-effective first-line treatment. Botulinum toxin A blocks presynaptic "
            "acetylcholine release at the neuromuscular/neuroeccrine junction, preventing sweating for months. "
            "Oxybutynin is an anticholinergic that inhibits muscarinic receptors on sweat glands; limited by "
            "side effects (dry mouth, constipation). (Fitzpatrick's Dermatology 9e; Andrews' Diseases of the Skin)"
        ),
    },
    {
        "no": 29,
        "title": "Pemphigus Vulgaris",
        "patient": "45-year-old female | Presenting complaint: Painful oral erosions for 3 months, now flaccid blisters and erosions on the trunk; Nikolsky sign positive; biopsy shows intraepidermal acantholysis; ELISA: anti-desmoglein 3 antibodies positive",
        "diagnosis": "Pemphigus Vulgaris",
        "prescription": [
            ("Prednisolone 1 mg/kg/day orally", "Take with food; morning dose to minimise HPA axis suppression", "Tapering course – reduce by 10 mg every 4 weeks once in remission"),
            ("Azathioprine 1–3 mg/kg/day (steroid-sparing)", "Check TPMT enzyme level before starting; take with food", "Long-term adjunct – allows steroid reduction"),
            ("Rituximab 1000 mg IV (for refractory or severe disease)", "Two infusions 2 weeks apart; repeat at 6 months if needed", "As needed per disease activity"),
            ("Pantoprazole 40 mg", "Once daily in morning (gastric protection during steroid use)", "Throughout steroid course"),
            ("Calcium 500 mg + Vitamin D3 400 IU daily", "Bone protection during long-term steroids", "Throughout steroid course"),
        ],
        "rationale": (
            "Pemphigus vulgaris is an IgG autoimmune blistering disease caused by antibodies against "
            "desmoglein 1 and 3 (desmosomal proteins), disrupting keratinocyte adhesion and causing "
            "intraepidermal blister formation. High-dose corticosteroids are the cornerstone of acute treatment. "
            "Azathioprine (thiopurine) is a steroid-sparing immunosuppressant; TPMT testing prevents dangerous "
            "myelosuppression. Rituximab (anti-CD20) depletes B cells producing the pathogenic antibodies and "
            "is now considered first-line for moderate-severe PV per recent guidelines. Proton pump inhibitors "
            "and bone protection are essential co-medications with long-term steroids. (Fitzpatrick's 9e)"
        ),
    },
    {
        "no": 30,
        "title": "Bullous Pemphigoid",
        "patient": "72-year-old male | Presenting complaint: Pruritic urticarial plaques followed by large tense blisters on the trunk and limbs for 4 weeks; Nikolsky sign negative; IF: IgG at DEJ",
        "diagnosis": "Bullous Pemphigoid",
        "prescription": [
            ("Clobetasol propionate 0.05% cream", "Apply to entire body once daily (super-potent topical corticosteroid is first-line for BP)", "4 weeks then taper"),
            ("Doxycycline 100 mg twice daily + Niacinamide 500 mg 3 times daily", "Oral (steroid-sparing combination for milder disease)", "3–6 months"),
            ("Prednisolone 0.5 mg/kg/day (for severe/extensive disease)", "With gastric and bone protection", "Tapering over months"),
            ("Calcium 500 mg + Vitamin D3 400 IU daily", "Bone protection", "Throughout steroid course"),
        ],
        "rationale": (
            "Bullous pemphigoid is caused by IgG autoantibodies (anti-BP180/BP230) targeting hemidesmosomes "
            "at the dermoepidermal junction, causing subepidermal blistering. Unlike PV, BP blister is tense "
            "because it is subepidermal. Strong topical corticosteroid (clobetasol) is first-line and has "
            "fewer systemic side effects than oral prednisolone in the elderly – who are particularly vulnerable "
            "to steroid complications. Doxycycline + niacinamide inhibit blister formation via anti-inflammatory "
            "mechanisms (metalloproteinase inhibition). (Fitzpatrick's 9e; Andrews' Diseases of the Skin)"
        ),
    },
]

# ---------------------------------------------------------------------------
# PDF BUILD
# ---------------------------------------------------------------------------

def build_pdf():
    doc = SimpleDocTemplate(
        OUTPUT,
        pagesize=A4,
        rightMargin=18*mm,
        leftMargin=18*mm,
        topMargin=20*mm,
        bottomMargin=20*mm,
        title="Dermatology OPD Cases – Educational Reference",
        author="Orris Medical Education",
        subject="Dermatology Clinical Cases with Prescriptions and Rationale",
    )

    styles = getSampleStyleSheet()

    # Custom styles
    title_style = ParagraphStyle(
        "MainTitle",
        parent=styles["Title"],
        fontSize=22,
        textColor=colors.HexColor("#1a3a5c"),
        spaceAfter=6,
        alignment=TA_CENTER,
        fontName="Helvetica-Bold",
    )
    subtitle_style = ParagraphStyle(
        "Subtitle",
        parent=styles["Normal"],
        fontSize=12,
        textColor=colors.HexColor("#4a6fa5"),
        spaceAfter=4,
        alignment=TA_CENTER,
        fontName="Helvetica",
    )
    disclaimer_style = ParagraphStyle(
        "Disclaimer",
        parent=styles["Normal"],
        fontSize=8,
        textColor=colors.HexColor("#888888"),
        spaceAfter=16,
        alignment=TA_CENTER,
        fontName="Helvetica-Oblique",
    )
    case_header_style = ParagraphStyle(
        "CaseHeader",
        parent=styles["Heading2"],
        fontSize=13,
        textColor=colors.white,
        spaceAfter=4,
        spaceBefore=2,
        fontName="Helvetica-Bold",
        leftIndent=6,
    )
    section_label_style = ParagraphStyle(
        "SectionLabel",
        parent=styles["Normal"],
        fontSize=9,
        textColor=colors.HexColor("#1a3a5c"),
        fontName="Helvetica-Bold",
        spaceAfter=2,
        spaceBefore=4,
    )
    body_style = ParagraphStyle(
        "Body",
        parent=styles["Normal"],
        fontSize=9,
        textColor=colors.HexColor("#333333"),
        fontName="Helvetica",
        spaceAfter=4,
        leading=13,
        alignment=TA_JUSTIFY,
    )
    patient_style = ParagraphStyle(
        "Patient",
        parent=styles["Normal"],
        fontSize=9,
        textColor=colors.HexColor("#2c5f2e"),
        fontName="Helvetica",
        spaceAfter=4,
        leading=13,
    )
    dx_style = ParagraphStyle(
        "Diagnosis",
        parent=styles["Normal"],
        fontSize=10,
        textColor=colors.HexColor("#8b1a1a"),
        fontName="Helvetica-Bold",
        spaceAfter=6,
    )
    toc_style = ParagraphStyle(
        "TOC",
        parent=styles["Normal"],
        fontSize=9,
        textColor=colors.HexColor("#222222"),
        fontName="Helvetica",
        leading=14,
        spaceAfter=1,
    )
    toc_header_style = ParagraphStyle(
        "TOCHeader",
        parent=styles["Normal"],
        fontSize=13,
        textColor=colors.HexColor("#1a3a5c"),
        fontName="Helvetica-Bold",
        spaceBefore=8,
        spaceAfter=10,
    )

    story = []

    # --- COVER ---
    story.append(Spacer(1, 30*mm))
    story.append(Paragraph("DERMATOLOGY OPD", title_style))
    story.append(Paragraph("Clinical Cases for Practice &amp; Education", title_style))
    story.append(Spacer(1, 8*mm))
    story.append(HRFlowable(width="80%", thickness=2, color=colors.HexColor("#4a6fa5"), hAlign="CENTER"))
    story.append(Spacer(1, 8*mm))
    story.append(Paragraph("30 Real-World Cases with Full Prescriptions &amp; Pharmacological Rationale", subtitle_style))
    story.append(Spacer(1, 6*mm))
    story.append(Paragraph(
        "Conditions Covered: Acne · Eczema · Psoriasis · Tinea · Scabies · Urticaria · "
        "Contact Dermatitis · Seborrhoeic Dermatitis · Pityriasis Versicolor · "
        "Herpes Zoster &amp; Simplex · Molluscum · Warts · Rosacea · Vitiligo · Melasma · "
        "Alopecia · Onychomycosis · Drug Rash · Lichen Planus · Hyperhidrosis · "
        "Pemphigus Vulgaris · Bullous Pemphigoid · and more",
        subtitle_style
    ))
    story.append(Spacer(1, 14*mm))
    story.append(Paragraph(
        "Sources: Fitzpatrick's Dermatology (9e) · Andrews' Diseases of the Skin (13e) · "
        "Dermatology 2-Volume Set (5e) · Harrison's Principles of Internal Medicine (22e) · "
        "Goldman-Cecil Medicine · Red Book 2021",
        disclaimer_style
    ))
    story.append(Paragraph(
        "FOR EDUCATIONAL USE ONLY · Not for direct clinical application without clinical judgement · "
        "Doses must be verified against local formulary and patient-specific factors",
        disclaimer_style
    ))
    story.append(Spacer(1, 30*mm))
    story.append(PageBreak())

    # --- TABLE OF CONTENTS ---
    story.append(Paragraph("Table of Contents", toc_header_style))
    story.append(HRFlowable(width="100%", thickness=1, color=colors.HexColor("#cccccc")))
    story.append(Spacer(1, 4*mm))
    for case in CASES:
        story.append(Paragraph(f"Case {case['no']:02d}  ·  {case['title']}", toc_style))
    story.append(PageBreak())

    # --- CASES ---
    for case in CASES:
        block = []

        # Coloured header bar using a 1-row table
        header_data = [[Paragraph(
            f"CASE {case['no']:02d}  |  {case['title'].upper()}",
            case_header_style
        )]]
        header_table = Table(header_data, colWidths=[doc.width])
        header_table.setStyle(TableStyle([
            ("BACKGROUND", (0,0), (-1,-1), colors.HexColor("#1a3a5c")),
            ("ROWBACKGROUNDS", (0,0), (-1,-1), [colors.HexColor("#1a3a5c")]),
            ("TOPPADDING", (0,0), (-1,-1), 7),
            ("BOTTOMPADDING", (0,0), (-1,-1), 7),
            ("LEFTPADDING", (0,0), (-1,-1), 10),
            ("RIGHTPADDING", (0,0), (-1,-1), 10),
            ("ROUNDEDCORNERS", [3, 3, 0, 0]),
        ]))
        block.append(header_table)

        # Patient info
        block.append(Spacer(1, 3))
        block.append(Paragraph("PATIENT PRESENTATION", section_label_style))
        block.append(Paragraph(case["patient"], patient_style))

        # Diagnosis
        block.append(Paragraph(f"DIAGNOSIS:  {case['diagnosis']}", dx_style))

        # Prescription table
        block.append(Paragraph("PRESCRIPTION (Rx)", section_label_style))
        rx_data = [["Drug / Item", "Directions", "Duration"]]
        for drug, directions, duration in case["prescription"]:
            if drug and directions:
                rx_data.append([
                    Paragraph(drug, ParagraphStyle("D", parent=styles["Normal"], fontSize=8, fontName="Helvetica-Bold", textColor=colors.HexColor("#1a3a5c"))),
                    Paragraph(directions, ParagraphStyle("I", parent=styles["Normal"], fontSize=8, fontName="Helvetica")),
                    Paragraph(duration, ParagraphStyle("Du", parent=styles["Normal"], fontSize=8, fontName="Helvetica")),
                ])
            elif drug:
                # advice row – span all columns
                rx_data.append([
                    Paragraph(f"⚕ {drug}", ParagraphStyle("A", parent=styles["Normal"], fontSize=8, fontName="Helvetica-Oblique", textColor=colors.HexColor("#555555"))),
                    "", ""
                ])

        col_widths = [doc.width * 0.36, doc.width * 0.43, doc.width * 0.21]
        rx_table = Table(rx_data, colWidths=col_widths, repeatRows=1)
        rx_table.setStyle(TableStyle([
            ("BACKGROUND", (0,0), (-1,0), colors.HexColor("#4a6fa5")),
            ("TEXTCOLOR", (0,0), (-1,0), colors.white),
            ("FONTNAME", (0,0), (-1,0), "Helvetica-Bold"),
            ("FONTSIZE", (0,0), (-1,0), 8),
            ("ROWBACKGROUNDS", (0,1), (-1,-1), [colors.HexColor("#f5f7fa"), colors.white]),
            ("GRID", (0,0), (-1,-1), 0.3, colors.HexColor("#cccccc")),
            ("TOPPADDING", (0,0), (-1,-1), 5),
            ("BOTTOMPADDING", (0,0), (-1,-1), 5),
            ("LEFTPADDING", (0,0), (-1,-1), 6),
            ("RIGHTPADDING", (0,0), (-1,-1), 6),
            ("VALIGN", (0,0), (-1,-1), "TOP"),
        ]))
        block.append(rx_table)

        # Rationale
        block.append(Spacer(1, 4))
        block.append(Paragraph("PHARMACOLOGICAL RATIONALE", section_label_style))
        rationale_data = [[Paragraph(case["rationale"], body_style)]]
        rationale_table = Table(rationale_data, colWidths=[doc.width])
        rationale_table.setStyle(TableStyle([
            ("BACKGROUND", (0,0), (-1,-1), colors.HexColor("#fdf6e3")),
            ("LEFTPADDING", (0,0), (-1,-1), 8),
            ("RIGHTPADDING", (0,0), (-1,-1), 8),
            ("TOPPADDING", (0,0), (-1,-1), 6),
            ("BOTTOMPADDING", (0,0), (-1,-1), 6),
            ("BOX", (0,0), (-1,-1), 0.5, colors.HexColor("#e8c870")),
        ]))
        block.append(rationale_table)
        block.append(Spacer(1, 10*mm))

        story.append(KeepTogether(block))

    # Build
    doc.build(story)
    print(f"PDF saved to: {OUTPUT}")

if __name__ == "__main__":
    build_pdf()