What Causes Shingles in a 6-Year-Old Female
Shingles in a 6-year-old results from reactivation of varicella-zoster virus (VZV) that became latent in her dorsal root ganglia following either primary chickenpox infection or, less commonly, varicella vaccination. 1
Mechanism of Disease
- After primary varicella infection (chickenpox), VZV establishes latency in neuronal ganglia along the entire neuraxis, where it remains dormant until reactivation occurs 1, 2
- Reactivation from dorsal root ganglia produces the characteristic dermatomal rash and pain of herpes zoster 3, 4
- The virus spreads from the ganglion to the skin, creating a unilateral vesicular eruption following a specific dermatome 4
Risk Factors in Young Children
The most important clinical consideration is whether an underlying immunodeficiency exists, though isolated uncomplicated childhood herpes zoster is unlikely to indicate immunodeficiency. 5
Reassuring Features (Lower Concern for Immunodeficiency)
- Exposure to VZV prior to 1 year of age significantly increases risk of childhood herpes zoster, as children who acquire chickenpox during infancy have an increased risk of developing shingles 1, 5
- Incomplete or compromised VZV vaccination schedule 5
- Single episode of uncomplicated herpes zoster 5
- Primary VZV infection during infancy is more common in immunocompetent children who later develop herpes zoster 6
Concerning Features (Higher Suspicion for Immunodeficiency)
- Recurrent herpes zoster during a short period 5
- Disseminated herpes zoster involving multiple dermatomes 5
- New lesions appearing more than one week after initial presentation 5
- Prolonged course despite appropriate antiviral medications 5
- History of recurrent, invasive, or prolonged infections by other pathogens 5
- Family history of immunodeficiency or consanguinity 5
Specific Immunodeficiency Conditions Associated with Pediatric Herpes Zoster
- T-cell immune defects are the primary immunologic abnormality predisposing to herpes zoster 5
- HIV infection 5, 3
- Tuberculosis and other chronic infections 5
- Diabetes mellitus 5
- Malnutrition 5
- Hematologic malignancies and other cancers 5, 6
- Primary immunodeficiency disorders 5
- Chronic corticosteroid use 3
- Chemotherapy 3, 6
Vaccine-Type Herpes Zoster
- In children previously vaccinated for VZV, the possibility of vaccine-type herpes zoster must be considered, as the live-attenuated Oka strain vaccine virus can also establish latency and later reactivate 1, 5
- Available data indicate that the risk of herpes zoster after immunization appears lower than the risk after wild-type varicella infection 1
Common Pitfall to Avoid
Do not assume that childhood herpes zoster automatically indicates serious immunodeficiency. Herpes zoster in children is rare but can occur in otherwise healthy children, particularly those who had chickenpox during infancy 1, 5. The key is distinguishing between isolated uncomplicated cases (which are usually benign) and cases with concerning features that warrant immunologic evaluation 5.
Initial Evaluation Approach
- Confirm normal newborn screening for profound T-cell immunodeficiency 5
- Complete blood count with differential 5
- Quantitative serum immunoglobulins 5
- Lymphocyte subset analysis 5
- Presence of IgG antibody to VZV 5
- If concerning clinical or laboratory features are present, refer to an experienced immunology specialist 5