SARS-CoV-2 messenger RNA vaccination during herpes zoster infection in an elderly man

To the Editor: With reference to the manuscript “SARS-CoV-2 mRNA vaccination and subsequent herpes zoster: Possible immune reconstitution by mRNA vaccination,”¹ we would like to present a unique case of messenger RNA (mRNA) vaccination during herpes zoster infection in an elderly man.

The patient is an 84-year–old man who presented with a 3-day history of herpes zoster (HZ) in the right first division of the trigeminal nerve (Fig 1). He had noticed the rash on the day of the first BNT162b2 mRNA vaccination, but he went on to receive the vaccine regardless. He had a medical history of cerebral infarction. He had not been vaccinated against HZ. Laboratory investigations revealed a normal white blood cell count (4.0 × 10³/μL) and a slightly increased C-reactive protein level (0.53 mg/dL; normal level, <0.30 mg/dL). The varicella-zoster virus–specific IgG titer was 25.1 (negative, <2). Other laboratory data were unremarkable. Immediately, treatment with a 1-week course of intravenous acyclovir at 750 mg/day was initiated. On the fourth day of hospitalization, the vesicles had begun to coalesce into large erosions and become hemorrhagic crusts, but poorly demarcated edematous erythema without tenderness or pruritus expanded on the entire face (Fig 2). He had an intermittent fever of up to 38.8 °C, and his serum C-reactive protein level had elevated to 10.61 mg/dL without leukocytosis. Varicella-zoster virus–specific immunoglobulin M was detected at that time. Investigations did not reveal the presence of varicella-zoster virus meningitis, viremia, or any secondary bacterial infection in the HZ lesion. In addition, the results of systemic infectious workup did not reveal an obvious infection. In the absence of other causal factors, it was concluded that the HZ exhibited intense inflammation. His fever and facial erythema resolved without conventional administration of antibiotics on the ninth day of hospitalization, and the ulcerated skin lesions epithelized on the 25th day of hospitalization. No development of ophthalmic sequelae or postherpetic neuralgia was observed. The patient had the second dose of the vaccine without any adverse events.

Fig 1.

Herpes zoster in the right first division of the trigeminal nerve on the third day after onset.

Fig 2.

Poorly demarcated erythema and edema expanding on the entire face on the sixth day after onset (3 days after the initiation of treatment with acyclovir).

This study highlights a case of HZ with intense inflammation reflected by severe rash, fever, and a high C-reactive protein level. This manifestation may simply be because of the aging (ie, immunosenescence) of the patient because aging is a risk factor for developing severe HZ symptoms, especially postherpetic neuralgia.² However, this case is atypical for such a case because of the following aspects: lack of postherpetic neuralgia, systemically disseminated rash, no development of ophthalmic sequelae, and the start of intense inflammation 3 days after the initiation of intravenous acyclovir.

Immune reconstitution inflammatory syndrome can exhibit 2 clinical symptoms during immune response recovery: the appearance of pre-existing subclinical infections (unmasking immune reconstitution inflammatory syndrome) and the worsening of pre-existing apparent infections (paradoxical immune reconstitution inflammatory syndrome).³ Ota¹ proposed a possible immune reconstitution triggered by mRNA vaccination in a case of HZ, suggesting “unmasking” immune reconstitution by the vaccination. In contrast, HZ with intense inflammatory symptoms, as in the present case, highlights the potential “paradoxical” immune reconstitution triggered by the vaccination. Additional observations and vigilance are indicated; however, this type of clinical manifestation may be extremely rare because mRNA vaccination is not recommended for individuals suffering from an acute infection.

Conflicts of interest

None disclosed.