---

---

3rd Year Dermatology PG Theory Examination - Model Answers

---

Q6. STD Kits (10 Marks)

Introduction

Rationale for Syndromic Approach

• STDs are often mixed infections; treating all likely pathogens simultaneously improves outcomes
• Reduces loss to follow-up - treatment given at the first visit
• Cost-effective at primary health care level
• Prevents complications and interrupts transmission chain
• Particularly valuable in resource-limited settings where lab infrastructure is absent

Types of STD Kits (NACO, India)

Partner Treatment

• All kits include a partner treatment pack
• Partners are treated presumptively without clinical assessment
• Critical for interrupting the transmission chain and preventing reinfection

Limitations of STD Kits

• Overtreatment and polypharmacy
• Cannot identify specific pathogen
• May contribute to antibiotic resistance with widespread use
• Not suitable for treatment failures, complicated cases, or pregnancy
• Does not replace laboratory-based management when resources are available
• No kit covers ectoparasites (scabies, pubic lice) - require separate treatment

---

Q7. Histoid Leprosy; Lucio Leprosy (10 Marks)

HISTOID LEPROSY (5 Marks)

• Classically arises in patients on dapsone monotherapy due to drug resistance/relapse
• Also seen de novo in treatment-naive patients
• Bacilli adapt and produce characteristic spindle-shaped histiocytic cells
• Bacillary index (BI) is higher than in ordinary lepromatous leprosy

• Smooth, shiny, hemispherical, dome-shaped, nontender, soft-to-firm nodules
• Lesions appear on otherwise normal-looking skin (key differentiating feature)
• Subcutaneous, superficial, or fixed to deeper structures
• Sites: Face, back, buttocks, extremities, over bony prominences (especially elbows and knees)
• Number: few to several hundred
• May umbilicate; some coalesce into annular patterns
• Resembles dermatofibroma, xanthoma, or neurofibroma clinically

• Spindle-shaped (fusiform) histiocytic cells in storiform pattern - hallmark feature
• Unusually large numbers of AFB, including globi (rafts/packets of bacilli)
• BI much higher than ordinary LL leprosy

• Slit-skin smear: very high BI
• Skin biopsy: spindle-cell granuloma confirms diagnosis
• High index of suspicion required as it mimics many dermatologic conditions

---

LUCIO LEPROSY (5 Marks)

• Caused by M. lepromatosis - a distinct species closely related to but different from M. leprae
• Key pathogenesis: endothelial cell invasion by bacilli (unlike M. leprae)
• This endothelial tropism underpins both the clinical appearance and the Lucio phenomenon

• Diffuse, smooth, waxy, shiny skin infiltration (hence "lepra bonita")
• Obvious diffuse infiltration of ear lobes and forehead
• Madarosis (loss of eyebrows and eyelashes) and sometimes all body hair
• Hoarse voice (laryngeal infiltration)
• Numbness and edema of hands and feet (may mimic myxedema)
• Crucially: NO discrete nodules, NO lymphadenopathy, NO arthritis - this differentiates it from ENL

• A severe, specific reactional state unique to Lucio leprosy
• Presents as multiple, well-defined, angular, jagged purpuric lesions
• Evolves into massive ulcerations that spread in ascending fashion over extremities
• Heals with atrophic scarring
• Pathogenesis: Endothelial injury → fibrin thrombi → ischemic infarction → ulceration
• Treatment: Poorly responsive to corticosteroids and thalidomide; effective antimicrobial chemotherapy (MB-MDT) is the only recommended treatment, combined with wound management for leg ulcers

---

Q8. Rehabilitation in Leprosy; Atypical Presentation of Paucibacillary Leprosy (10 Marks)

REHABILITATION IN LEPROSY (6 Marks)

• Early diagnosis and prompt MDT to prevent nerve damage
• Treatment of reactions (Type 1 and ENL) with steroids to prevent irreversible nerve damage
• Ulcer care kits: Dressing materials and supportive medicines for leprosy patients with plantar ulcers and wounds (provided under NLEP including to leprosy colonies)
• Micro-cellular rubber (MCR) footwear: Protects insensitive feet from repeated trauma and plantar ulcers
• Self-care training: patients taught to inspect insensitive limbs daily, soak and oil dry skin, protect from burns and trauma
• Physiotherapy: active and passive exercises to prevent contractures, maintain joint mobility

• Lagophthalmos: Lateral tarsorrhaphy, gold weight implantation
• Claw hand: Flexor digitorum superficialis (FDS) tendon transfer
• Foot drop: Tibialis posterior transfer (Lambrinudi procedure)
• Wrist drop and thumb opposition deformity: Tendon transfer procedures
• Saddle nose: Cosmetic rhinoplasty

• Vocational training and livelihood support
• Micro-credit and self-help group formation
• Anti-stigma and IEC (Information, Education, Communication) campaigns
• ILEP (International Federation of Anti-Leprosy Associations): supports 36 NGOs for reconstructive surgery
• Legal protection: leprosy is no longer a ground for divorce under Indian law (Dissolution of Muslim Marriages Act amendment, 2019)

• ASHA worker involvement in detection and treatment completion
• Household contact surveys
• Integration with general health care system (since 2002-03)
• Tiered system: primary (wound care, MCR footwear, referral) → secondary/tertiary (RCS, PMR centers)

---

ATYPICAL PRESENTATIONS OF PAUCIBACILLARY (PB) LEPROSY (4 Marks)

• Sensory loss ± motor deficit along a nerve trunk with no skin lesions
• Accounts for 5-10% of leprosy in India and Nepal
• Nerve involvement generally asymmetrical; may be single or multiple
• Up to 1/3 of patients later develop skin lesions
• Diagnosis: nerve biopsy showing epithelioid granulomas

• Only one skin lesion - hypo/hyperpigmented patch
• Treatment: Single-dose ROM therapy (Rifampicin 600 mg + Ofloxacin 400 mg + Minocycline 100 mg)

• Type 1 (Reversal Reaction) may be the first presentation
• Sudden erythema, swelling, neuritis - the patient may not have noticed the original patch

• Hypo/depigmented patches mimic: vitiligo, pityriasis alba, tinea versicolor, NLD
• Annular lesions mimic: granuloma annulare, tinea corporis, DLE
• Key clue: hypoesthesia + anhidrosis + absence of hair within the patch

• Earlobe infiltration, nasal mucosal lesions, eyebrow involvement
• Purely neural involvement of a single small nerve branch mimicking nerve entrapment

• HIV coinfection can unmask leprosy or trigger immune reconstitution inflammatory syndrome (IRIS) presenting as a Type 1 reaction when ART is initiated

---

Q9. Prenatal Syphilis; Ulcerative STD and HIV Coinfection (10 Marks)

PRENATAL (CONGENITAL) SYPHILIS (6 Marks)

• Congenital syphilis has resurged globally; ~21% of perinatal deaths in sub-Saharan Africa are attributable to it
• Risk groups: mothers with no prenatal care, substance users, sex workers, those treated with non-penicillin regimens

• Treponema pallidum crosses the placenta from an infected mother (usually with early syphilis)
• Placental transmission does not occur before the 4th month (Langhans layer acts as barrier)
• Treatment before end of 2nd trimester almost always prevents adverse outcomes
• Risk from untreated early maternal syphilis: 40% fetal death/miscarriage + 40% syphilitic infant
• Fetal infection is rare when mother has had syphilis for >2 years

• Early congenital syphilis: Manifestations within first 2 years of life
• Late congenital syphilis: Manifestations after age 2 years

• 2/3 neonates appear normal at birth - detected only by serology
• Snuffles (syphilitic rhinitis): most frequent, often first sign - blood-stained nasal discharge, nasal obstruction; progressive ulceration causes saddle nose
• Cutaneous lesions (30-60%): Morbilliform rash → fading copper-brown; pemphigus syphiliticus (bullae on palms/soles); mucous patches; condylomata lata
• Hepatosplenomegaly, jaundice
• Osteochondritis/periostitis: Wimberger sign (bilateral destruction of medial tibial metaphyses on X-ray)
• Pseudoparalysis of Parrot: Immobility of limb from osteochondritis pain (mimics paralysis)
• CNS: Meningitis, hydrocephalus
• General appearance: Marasmic, fretful neonate with "old man face"

• Hutchinson's Triad (pathognomonic): Interstitial keratitis + Hutchinson's teeth + 8th nerve (sensorineural) deafness
• Hutchinson's teeth: Notched, barrel-shaped, peg-shaped upper central incisors (permanent teeth)
• Interstitial keratitis: Most common (40-80%) - photophobia, lacrimation, corneal vascularization
• Bone: Saber shins (anterior bowing of tibia from periostitis), Clutton's joints (painless bilateral synovitis of knees)
• Saddle nose, Rhagades (perioral linear scars from healed early papules)
• Neurosyphilis: Juvenile tabes dorsalis, seizures, intellectual disability
• Stigmata: Higouménakis sign (unilateral SCM enlargement), Moon's molars (dome-shaped first molars)

• All pregnant women: serologic testing at first antenatal visit AND at delivery
• Point-of-care RPR/VDRL tests used in resource-limited settings

• Penicillin is the ONLY drug proven effective; no validated alternative in pregnancy
• Erythromycin and azithromycin are NOT recommended for any stage of syphilis

1. No documented treatment of syphilis diagnosed before pregnancy
2. Absence of serologic testing during pregnancy
3. Late or no maternal treatment
4. Non-penicillin regimens used

---

ULCERATIVE STD AND HIV COINFECTION (4 Marks)

• Genital ulcers disrupt mucosal integrity, removing the first line of defense
• HIV-positive immune cells (CD4+ T cells, macrophages) are recruited to the ulcer site in large numbers
• Concentrated inflammatory infiltrate at the ulcer provides a highly susceptible target for HIV entry
• Estimated risk increase: 2-5 fold per sexual act

• HIV is shed in high concentrations in ulcer exudate
• HSV-2 shedding is dramatically increased in HIV-positive persons
• HSV-2 co-infection affects 50-90% of HIV-positive patients
• Syphilis coinfection increases HIV viral load AND decreases CD4 count, accelerating immunosuppression and disease progression

• All GUD patients must be offered HIV testing (and vice versa)
• Treatment of GUD reduces HIV transmission at the population level
• Suppressive HSV-2 therapy (Acyclovir 400 mg BD) in HIV-positive patients reduces both HIV shedding and HSV recurrences
• Modified syphilis treatment in HIV+ patients: some experts recommend 3 weekly doses of benzathine penicillin even for early syphilis
• Condom promotion and partner notification are essential

---

Q10. STD Investigations; Gonorrhoea Complications (10 Marks)

STD INVESTIGATIONS (5 Marks)

• Gram stain of discharge: Gram-negative intracellular diplococci; sensitivity 90-95% in symptomatic male urethritis, only ~50% in females and asymptomatic infections
• Culture on Thayer-Martin medium (chocolate agar + antibiotics to suppress commensals): Gold standard; allows antibiotic sensitivity testing - critical in era of resistance
• NAAT (Nucleic Acid Amplification Tests): Most sensitive and specific; uses urine, urethral, cervical, rectal, or pharyngeal swabs; preferred test at referral level

• NAAT: First-line - urine or genital swab; sensitivity >95%
• Cell culture in McCoy cells: Historical gold standard; technically demanding
• EIA/ELISA antigen detection: Less sensitive than NAAT
• Microimmunofluorescence (MIF): For LGV serology (L1-L3 serovars)

• Dark-field microscopy: Direct visualization of motile spirochetes from primary chancre or secondary lesions - gold standard for active lesions
• Non-treponemal tests (NTT): VDRL and RPR - screening and monitoring treatment response; titers fall with successful treatment; false positives in SLE, pregnancy, malaria, EBV
• Treponemal tests: TPHA, FTA-ABS, TPPA - confirmatory; remain positive lifelong even after treatment (cannot be used to monitor response)
• PCR: Available in specialized centers; useful for neurosyphilis (CSF), primary chancres

• Viral culture from vesicle base: Gold standard but sensitivity falls rapidly in healing lesions
• Tzanck smear: Multinucleated giant cells - rapid, inexpensive, low sensitivity (~50%)
• PCR/NAAT: Most sensitive, especially for late, atypical, or healing lesions; also used for CSF in HSV encephalitis
• Type-specific IgG serology: Distinguishes HSV-1 from HSV-2; useful for diagnosis between episodes

• Clinical diagnosis in most cases
• Acetowhitening (3-5% acetic acid): Reveals subclinical lesions as white areas
• Colposcopy + biopsy: For cervical/atypical lesions
• HPV DNA typing (PCR): Identifies high-risk strains (HPV 16, 18)
• Pap smear/Liquid-based cytology (LBC): Cervical cancer screening

• Culture on selective enriched chocolate agar: Sensitivity only 50-60% even under ideal conditions
• NAAT where available
• Often a clinical/exclusion diagnosis

• Wet mount microscopy: Direct visualization of motile flagellated trichomonads; sensitivity 60-70%
• Culture (InPouch TV): Gold standard; sensitivity ~95%
• NAAT: Highest sensitivity

• 4th generation Ag/Ab combination assay (screening) - detects p24 antigen + antibody
• Western blot or NAAT (confirmatory)
• CD4 count and viral load (staging and monitoring)

---

GONORRHOEA COMPLICATIONS (5 Marks)

A. LOCAL COMPLICATIONS IN MALES:

1. Epididymo-orchitis: Most common serious male complication; unilateral scrotal pain, swelling, tenderness; may lead to obstructive azoospermia and infertility
2. Prostatitis: Acute: urinary retention, perineal/rectal pain, tender boggy prostate; Chronic: perineal discomfort, obstructive symptoms
3. Cowperitis: Abscess of Cowper's (bulbourethral) glands; perineal swelling, pain on defecation, urinary retention
4. Tysonitis: Infection of Tyson's glands (preputial glands)
5. Periurethral abscess and Urethral stricture: Late fibrous complication from chronic inflammation; presents as poor urinary stream, dribbling; requires urethral dilatation or urethroplasty
6. Balanitis/Posthitis: Secondary infection of glans/prepuce

B. LOCAL COMPLICATIONS IN FEMALES:

1. Bartholinitis/Bartholin's abscess: Tender unilateral swelling at the 5 or 7 o'clock position of the vulva; fluctuant; may require incision and drainage or marsupialization
2. Skenitis: Infection of Skene's (paraurethral) glands
3. Cervicitis: Mucopurulent endocervical discharge, contact bleeding, cervical motion tenderness
4. Endometritis: Abnormal uterine bleeding, pelvic pain

C. REGIONAL/ASCENDING COMPLICATIONS (Pelvic Inflammatory Disease - PID):

• Ascending infection causes salpingitis, endometritis, and potentially tubo-ovarian abscess
• Fitz-Hugh-Curtis Syndrome: Perihepatitis from transperitoneal spread; presents as RUQ pain; "violin-string" adhesions between liver capsule and anterior abdominal wall (pathognomonic finding at laparoscopy)

• Infertility: 25% after one episode; 50% after two; 75% after three episodes (tubal factor infertility)
• Ectopic pregnancy: 10x increased risk from tubal scarring
• Chronic pelvic pain: Long-term sequela
• Recurrent PID: Each episode increases risk of all above complications

D. NEONATAL COMPLICATIONS:

• Acquired during passage through infected birth canal
• Onset: 2-5 days after birth (contrast with chlamydial ophthalmia: 5-14 days)
• Presents as severe bilateral purulent conjunctivitis; can rapidly progress to corneal ulceration, perforation, and permanent blindness
• Prophylaxis (Credé's method): 1% silver nitrate drops at birth; or erythromycin/tetracycline 0.5% eye ointment
• Treatment: Ceftriaxone 25-50 mg/kg IV/IM single dose

E. DISSEMINATED GONOCOCCAL INFECTION (DGI):

• Tenosynovitis (especially fingers, wrists, ankles) - pathognomonic of DGI
• Dermatitis: 1-20 scattered pustular, vesicular, hemorrhagic, or necrotic papulopustules on extremities
• Polyarthralgias/migratory polyarthritis
• Blood cultures often positive (50%)

• Purulent monoarthritis (knee most common; also wrist, ankle)
• Blood cultures usually negative; joint fluid culture positive
• Permanent joint damage if untreated

• Gonococcal endocarditis: Aortic valve most commonly; high mortality; requires 4 weeks treatment
• Gonococcal meningitis: Rare; requires high-dose IV penicillin/ceftriaxone
• Perihepatitis (Fitz-Hugh-Curtis): As described above

• Uncomplicated urogenital/anorectal/pharyngeal: Ceftriaxone 500 mg IM single dose (1g if weight >150 kg)
• If chlamydia not excluded: add Doxycycline 100 mg BD x 7 days
• DGI: Ceftriaxone 1g IV/IM daily x minimum 7 days
• Gonococcal endocarditis/meningitis: Ceftriaxone 1-2g IV every 12-24 hours for 4 weeks (endocarditis) / 10-14 days (meningitis)
• Ophthalmia neonatorum: Ceftriaxone 25-50 mg/kg IV/IM single dose
• Resistance note: Fluoroquinolone and penicillin resistance now widespread; XDR (ceftriaxone-resistant) strains emerging - culture + sensitivity essential for treatment failures

---