While “internal shingles” is not a formal medical diagnosis, it commonly refers to instances where the varicella-zoster virus (VZV) affects internal organs or parts of the nervous system beyond the typical skin rash. Shingles is a reactivation of VZV, the same virus that causes chickenpox. When this reactivation extends beyond the skin, it can lead to various complications.
How Shingles Affects the Body Systemically
After a chickenpox infection, the varicella-zoster virus (VZV) remains dormant within sensory nerve cells, specifically in the dorsal root ganglia or cranial nerves. This dormant state can persist for decades without symptoms. Factors like a weakened immune system, stress, or advancing age can trigger the virus to reactivate.
Upon reactivation, the virus multiplies within these nerve cells. It then travels along nerve pathways from these ganglia towards the skin, typically causing the characteristic painful rash in a specific area known as a dermatome. The pain often precedes the rash by several days.
In some cases, reactivated VZV spreads beyond these sensory nerves to affect other parts of the nervous system or internal organs. This systemic spread is colloquially referred to as “internal shingles.” The dormant virus can travel along different nerve branches to various bodily structures, causing symptoms beyond a skin eruption.
Signs Beyond the Skin
When shingles affects systems beyond the skin, its manifestations can be diverse, impacting vision, hearing, neurological function, and internal organs. These presentations depend on which nerve pathways the virus travels along and which areas it affects.
Shingles involving the eye, known as herpes zoster ophthalmicus (HZO), occurs when the virus reactivates in the trigeminal ganglion, impacting the ophthalmic nerve. Symptoms include a painful rash on the forehead, eyelid swelling, eye pain, redness, and sensitivity to light. Complications may range from inflammation of the conjunctiva, cornea (keratitis), or iris (uveitis) to increased eye pressure, chronic pain, and potential vision impairment or blindness.
When the virus affects the facial nerve near the ear, it can lead to Ramsay Hunt Syndrome (herpes zoster oticus). This condition causes facial weakness or paralysis, and a painful blistering rash on or around the ear, sometimes extending to the mouth. Patients may also experience ringing in the ears (tinnitus), hearing loss, and dizziness or vertigo.
Neurological complications arise if VZV spreads to the brain or spinal cord, leading to conditions like encephalitis (brain inflammation), meningitis (inflammation of the membranes surrounding the brain and spinal cord), or myelitis (spinal cord inflammation). These manifest as severe headaches, confusion, altered mental status, seizures, muscle weakness, or paralysis. In rare instances, VZV can cause vasculitis, an inflammation of blood vessels, increasing stroke risk, sometimes even without a preceding rash.
Visceral involvement, though rare, means the virus affects internal organs such as the lungs, liver, or gastrointestinal tract. Symptoms vary by organ, potentially including abdominal pain, nausea, vomiting, or organ-specific dysfunction. Disseminated zoster, characterized by a widespread rash and internal organ involvement, is more common in individuals with compromised immune systems.
Identifying and Managing Systemic Shingles
Diagnosing systemic shingles often begins with clinical suspicion, considering a patient’s history and symptoms, especially with a recent or current shingles rash. However, symptoms can be non-specific or occur without a rash, making diagnosis challenging. Laboratory tests, such as polymerase chain reaction (PCR) to detect VZV DNA in bodily fluids like cerebrospinal fluid (CSF) or affected tissue samples, are crucial for confirming the virus. Early and accurate diagnosis is important due to the potential severity of these manifestations.
Treatment primarily involves antiviral medications such as acyclovir, valacyclovir, or famciclovir. These medications inhibit the virus and are most effective when initiated within 72 hours of symptom onset. For severe cases or those involving internal organs, intravenous administration of antivirals, particularly acyclovir, may be necessary.
Supportive care is also key to management, including pain relief and addressing specific complications based on the affected organ system. For example, corticosteroids might reduce inflammation, and specific therapies are employed for eye or ear involvement. Hospitalization may be required for severe cases to manage complications and prevent further organ damage.
Protecting Against Shingles
Vaccination is a primary method for preventing shingles and its potential complications, including systemic involvement. The recombinant zoster vaccine, Shingrix, is recommended for adults aged 50 and older. This vaccine is administered as a two-dose series, usually 2 to 6 months apart, and has demonstrated high effectiveness in preventing shingles and postherpetic neuralgia.
Shingrix is over 90% effective at preventing shingles in adults 50 years and older with healthy immune systems. For individuals aged 19 and older with weakened immune systems, who are at higher risk for complications, vaccination is also recommended. While maintaining overall immune health through stress management and a healthy lifestyle can be supportive, vaccination remains the most effective preventive measure against shingles and its widespread effects.