Onset of Palmoplantar Pustulosis After COVID-19 Vaccination

A 46-year-old woman with a 20 pack-years history of smoking presented to an outpatient primary care clinic for evaluation of a recurrent painless rash on her palms and the soles of her feet. The rash had been present for 3 months prior to outpatient presentation but was initially noticed by the patient 2 weeks after receiving the first dose in the Moderna mRNA COVID-19 vaccine primary series.

History. The rash began as fluid filled lesions with drainage upon disruption of the surface approximately 2 weeks after receiving the first vaccine. The rash on her palms then worsened 4 weeks later, after receiving the second dose of the Moderna mRNA COVID-19 vaccine primary series. Her symptoms improved intermittently over the course of months but remained largely unchanged (Figures 1 and 2).

Figures 1 & 2. Erythematous pustular eruption on the bilateral soles, which worsened after receiving the second dose of the Moderna COVID-19 vaccine.

The patient reported pruritus but denied any fevers, pain, numbness, mucosal lesions, or upper respiratory symptoms. She denied the use of any new products, any history of a similar rash, or anyone in the home with similar symptoms. She works at an assembly line and wears gloves occasionally but denied being exposed to new chemicals or products. Her family history was significant for psoriasis and type I diabetes.

Approximately 3 months after the development of the rash, the patient’s primary care physician reported discrete red macules and deep-seated pustules on the bilateral plantar feet and palms. The patient reported minimal improvement with the use of over-the-counter cortisone or petrolatum, thus betamethasone dipropionate 0.05% cream was initiated.

Diagnostic testing. The patient was advised to return for a culture to rule out infectious causes. However, this was never completed. The patient was also referred to a dermatology specialist for evaluation of palmoplantar pustulosis.

At her visit with the dermatology specialist approximately 9 months after first developing the rash, the patient reported a lack of improvement with the betamethasone dipropionate cream. The patient had worsening symptoms on her palms and soles after receiving a Moderna mRNA booster vaccine about 7 weeks prior to presentation to the dermatologist (Figures 3 & 4). On examination, the palms and soles had resolving hyperpigmented macules with a few scattered pustules. No immunofluorescence or histopathology was obtained.

Figures 3 & 4. Erythematous pustular eruption on the bilateral palms after receiving the booster vaccine 7 weeks prior.

Differential diagnoses. Our differential diagnosis included dyshidrotic eczema, allergic contact dermatitis, irritant contact dermatitis, xerosis, chemical exposure, drug eruption, and hand, foot, and mouth disease. Given the morphology, distribution, and time course of the disease in addition to lack of recent infections or drug/chemical exposures, the other diagnoses were ruled out.

Treatment and management. While our case patient had no known history of prior disease, the presence of multiple risk factors, such as significant smoking history and family history of psoriasis, in addition to the pustular lesions was consistent with palmoplantar pustulosis after the administration of each COVID-19 vaccination.  Due to lack of improvement with betamethasone, the patient was started on tacrolimus 0.1% ointment to apply to the affected area twice daily until resolution of symptoms, with a close follow-up appointment 2 months later. Smoking cessation counseling was provided; however, the patient was not interested in quitting at the time. The patient was informed of the importance of notifying future providers of the post-vaccination reaction and was still advised to continue with normally scheduled vaccination recommendations given the substantial benefits.

Outcome and follow-up. The outcome of the intervention is unknown as the patient was lost to follow up.

Discussion. Palmoplantar pustulosis is a rare inflammatory skin condition, found in up to 0.12% of the population.¹ Recurrent sterile pustules form on the palms and soles, leading to scale, erythema, and pain. Due to the location of the lesions, there is significant reduction in quality of life from discomfort and disability.² Palmoplantar pustulosis is also therapeutically challenging, with topical and systemic treatments showing limited efficacy. Topical steroids, oral retinoids, and psoralen and ultraviolet A therapy are the most common treatment modalities; however, improvement is minor and recurrence can occur.² Although there is no known etiology, age between 40 to 69 years, female sex, smoking, infections, allergies, medications, autoimmune disease, and family history of psoriasis are all risk factors.^1-3

Palmoplantar pustulosis and other cutaneous diseases such as psoriasis vulgaris and generalized pustular psoriasis have been documented following the onset of COVID-19 infection and vaccination.^4-7 However, there have been no reports documenting a patient with new onset palmoplantar pustulosis after the COVID-19 vaccine without a previous history of similar symptoms. Viral infections, including COVID-19, and the administration of vaccines have been associated with the onset of dermatologic manifestations and inflammatory reactions such as local injection site reactions, transient rashes, and urticaria.⁸

One possible cause of delayed cutaneous reactions is the activation of the adaptive immune system and T cell-mediated processes.² Similarly, psoriasis and other variants such as palmoplantar pustulosis have been shown to be driven by T cell-mediated processes and cytokines IL-17 and IL-23.⁹ While rare, the development of cutaneous reactions after administration of the vaccine may be influenced by underlying risk factors as seen in our patient – age, sex, and smoking history. Her smoking history may have lowered the threshold and made her more susceptible to this eruption after vaccination.

It is important to note that the benefits from the vaccine outperform the risks reported here and that the development of cutaneous reactions such as palmoplantar pustulosis is not a contraindication to vaccination. Due to rising skepticism surrounding the vaccine, it is important for physicians to continue learning possible triggers and to counsel patients to reduce adverse events and improve adherence. By understanding these risks, we can provide adequate counseling surrounding vaccination risk and provide early treatment and management to control symptom onset.

Conclusion. Vaccinations can be associated with dermatologic manifestations and understanding the underlying risks and possible triggers may help improve counseling and management of these conditions. The adverse effects of the COVID-19 vaccine are continuing to be evaluated and understood. With new reactions arising, such as the onset of palmoplantar pustulosis in a patient with no previous symptoms, educating patients and recognizing possible risk factors are critical for transparency and confidence regarding the vaccine.

AFFILIATIONS
¹Department of Dermatology, Massachusetts General Hospital, Boston, MA
²Harvard Medical School, Boston, MA

CITATION
Silence C, Kourosh AS. Onset of palmoplantar pustulosis after COVID-19 vaccination. Consultant. 2023;63(9):e5. doi:10.25270/con.2023.08.000011.

Received December 28, 2022. Accepted March 1, 2023. Published online August 17, 2023.

DISCLOSURES
The authors report no relevant financial relationships.

ACKNOWLEDGEMENTS
None.

CORRESPONDENCE
Channi Silence, Department of Dermatology, Massachusetts General Hospital, 55 Fruit Street, BAR 622, Boston, MA 02114 (silencechanni@gmail.com)