VESICULOBULLOUS LESIONS (VIRAL - VARICELLA ZOSTER VIRUS)

Question 1

CONCEPT

Answer 1

• VZV ALSO KNOWS AS HUMAN HERPES VIRUS 3 (HHV-3)
• VIRUS SPREAD THROUGH AIR DROPLETS OR DIRECT CONTACT WITH ACTIVE LESIONS
• LIKE THE HSV-1 VIRUS, VZV BECOMES DORMANT IN NERVE GANGLION AFTER ITS PRIMARY INFECTION
• VZV CAUSE 2 WELL KNOWN DISEASES:
  1) CHCKENPOX (VARICELLA)
  2) HERPES ZOSTER (SHINGLES)

Question 2

VARICELLA (CHICKENPOX)

Answer 2

• PRIMARY INFECTION WITH VZV
• SYMPTOMATIC (IF COMPARE WITH HSV)
• SYMPTOMATIC PHASE: FEVER, CHILLS, MALAISE, PHARYNGITIS, HEADACHE
• APPEARANCE OF A PRURITIC VESICULAR RASH (BEGINS ON THE FACE AND TRUNK/EVENTUALLY EXTREMITIES
• VESICULES EVENTUALLY BECOME PUSTULES (HARDEN/SCAB OVER)
• LESIONS: RELATIVELY PAINLESS (ORAL LESIONS - OFTEN ON THE PALATE/BUCCAL MUCOSA)
• MILD CASES: ULCERS HEAL 1-3 DAYS
• SEVERE INFECTIONS: ULCERS PERSIST 5-10 DAYS
• CHILDHOOD COMPLICATIONS: SECONDARY SKIN INFECTIONS, FOLLOWED BY ENCEPHALITIS
• TREATMENT: ANALGESICS/ANTIPRURITIC
• ACETAMINOPHEN: PREFERRED ANTIPYRETIC CHILDHOOD CASES
• ASPIRIN: AVOIDED (RISK REYE’S SYNDROME)

Question 3

HERPES ZOSTER (SHINGLES)

Answer 3

• AFTER VZV INFECTION VIRUS IS TRANSPORTED UP THE SENSORY NERVES/ESTABLISHES LATENCY (DORSAL ROOT GANGLIA)
• CLINICALLY EVIDENT: HERPES ZOSTER DEVELOPS AFTER REACTIVATION OF THE VIRUS (INVOLVEMENT OF THE DISTRIBUTION OF THE AFFECTED SENSORY NERVE)
• PREDISPOSING FACTORS REATIVATION: IMMUNOSUPPRESSION, HIV, CYTOTOXIC/IMMUNOSUPPRESSIVE DRUGS, RADIATION, MALIGNANCY, OLD AGE, ALCOHOL ABUSE, STRESS, DENTAL MANIPULATION
• ONE RECURRENCE/PREVALENCE OF THE ATTACKS INCREASES WITH OLD AGE
• PAINFUL VESICLES (SKIN/MUCOSAL SURFACES) ALONG THE DISTRIBUTION OF A SENSORY NERVE (DISTINCTIVE UNILATERAL PATTERN)
• ORAL LESIONS OCCUR WITH TRIGEMINAL NERVE (DO NOT CROSS THE MIDLINE) - MOVABLE OR BOUND MUCOSA
• COMPLICATIONS: RAMSAY HUNT SYNDROME (CHARACTERIZED BY CUTANEOUS LESIONS OF THE EXTERNAL AUDITORY CANAL, INVOLVEMENT OF THE IPSILATERAL FACIA/AUDITORY NERVES, FACIAL PARALYSIS, HEARING DEFICITS, VERTIGO
• TREATMENT: ANTIVIRALS (ACYCLOVIR) - REDUCING HEALING TIME/REDUCING LIKELIHOOD OF DEVELOPING POST-HERPETIC NEURALGIA
• SUPPORTIVE THERAPY: ANTIPRURITICS (DEPHENHYDRAMINE) AND NON-ASPIRIN ANTIPYRETICS
• CLINICAL FEATURES: 3 PHASES: PRODROME/ACUTE/CHRONIC
  1) PRODROME: 1-4 DAYS BEFORE DEVELOPMENT LESIONS (SKIN/MUCOSA). VIRUS REPLICATING (CAUSES NEURAL NECROSIS/SEVERE NEURALGIA). PAIN SEVERE, SENSITIVE TOOTH, HEADACHE, OTITIS MEDIA
  2) ACCUTE PHASE: CLUSTERS OF VESICULES (SKIN/MUCOSA) 1-4 mm SIZE. 3-4 DAYS VESICLES ULCERATE. HEAL 2-3 WEEKS IN HEALTHY PATIENTS
  3) CHRONIC PHASE: 15% PATIENTS PROGRESS TO THE CHRONIC PHASE OF HERPES ZOSTER (POSTHERPETIC NEURALGIA). PERSISTENT PAIN 1-3 MONTHS AFTER RESOLUTION OF THE RASH. RISK FACTORS (FEMALE GENDER, OLDER AGE, HISTORY OF PRODROMAL PAIN, MODERATE TO SEVERE RASH AND/OR PAIN DURING ACUTE PHASE, OPHTHALMIC INVOLVEMENT. PAIN (BURNING, THROBBING, ACHING, ICHING, STABBING (AGGRAVATED BY TOUCH)