hydroa vacciniformeEBVvarioliform scarsHVLPD

Hydroa Vacciniforme

הידרואה וקסיניפורמה

📖 מבוא

Hydroa vacciniforme (HV) — photodermatosis נדירה של הילדות. Vesiculopapular eruption באזורי חשיפה לשמש → umbilicated vesicles → varioliform (pox-like) scars. קשר ל-EBV (chronic active EBV infection). ⚠️ HV-like lymphoproliferative disorder — aggressive NK/T-cell lymphoma. Bologna Ch 134.

📝 אנמנזה

בועות/שלפוחיות על עור חשוף לשמש? מותירות צלקות varioliform (דמויות אבעבועות)? גיל התחלה? (childhood). עונתיות — אביב/קיץ? כאב, צריבה לפני הופעה? חום, malaise? ⚠️ EBV symptoms? Lymphadenopathy?

🔍 בדיקה

Vesicles → umbilicated → necrotic crusts → varioliform scars (pathognomonic). Distribution: face, ears, dorsal hands — sun-exposed areas. Episodic, seasonal (spring-summer). ⚠️ HV-like lymphoproliferative disorder (HVLPD): facial edema, high fever, hepatosplenomegaly, deep tissue necrosis, NK/T-cell infiltrate — aggressive, poor prognosis, more common in Latin America/Asia.

📋 סיכום

ממצאים מתאימים להידרואה וקסיניפורמה. בירור EBV.

💊 המלצות

🔬 בירור

-Classic HV vs HV-like lymphoproliferative disorder (HVLPD): Classic — benign, self-limited, resolves by adulthood. HVLPD (⚠️ WHO classification: EBV+ NK/T-cell LPD) — progressive, systemic symptoms, hepatosplenomegaly, hemophagocytic syndrome, high mortality. HVLPD more common in: Latin America, Asia, Indigenous populations. Spectrum: classic HV → severe HV → HVLPD.

-בירור: EBV viral load (quantitative PCR) — elevated in HVLPD. EBV serology (VCA IgG/IgM, EBNA). CBC + diff (atypical lymphocytes, cytopenias). LFTs, LDH (elevated = aggressive). Biopsy: reticular degeneration of epidermis, lymphocytic vasculitis, necrosis. ⚠️ If HVLPD suspected: immunophenotyping (CD56+, CD3ε+, EBV-encoded RNA [EBER]+), bone marrow biopsy, PET-CT staging.

💊 טיפול

-טיפול classic HV: Strict photoprotection — broad-spectrum SPF 50+, UVA-protective clothing, UV-filtering window film. Phototherapy (hardening) — spring course of NB-UVB to build tolerance before summer. Antimalarials (HCQ 200 מ"ג/יום) — some benefit. Thalidomide 50-100 מ"ג/יום — effective but ⚠️ teratogenic, neuropathy. Self-resolves by late adolescence in most.

-HVLPD treatment: ⚠️ Hematology-oncology referral urgent. Chemotherapy (SMILE protocol: dexamethasone, methotrexate, ifosfamide, L-asparaginase, etoposide). Allogeneic HSCT — only curative option. Monitoring EBV viral load.

📅 מעקב

-ביקורת בתחילת עונת האביב. EBV viral load q6-12m.

⚗ מרשם

-PO HYDROXYCHLOROQUINE 200 mg/d (photoprotective) - 1OP

-SPF 50+ broad-spectrum sunscreen (high UVA protection) daily - OTC