Pain management of pemphigus vulgaris

Abstract

Pemphigus is a rare autoimmune bullous disease which affects the mucous membranes and skin. Pemphigus vulgaris (PV) is the most prevalent type of pemphigus. PV presents with extremely painful, non-healing oral erosions. However, there are only a handful of reports addressing the pain management of PV. We would like to present a case of a painful PV, which was successfully managed.

Background

Pemphigus is a rare autoimmune bullous disease which affects the mucous membranes and skin.¹ The cause of the disease is due to the production of autoantibodies against desmosomal structural proteins. This will then induce a loss of epidermal keratinocyt adhesions, resulting in the formation of intraepidermal blisters hence the development of vesicles and erosions. ²

Pemphigus vulgaris (PV) is the most prevalent type of pemphigus. PV presents with painful erosions and non-healing oral ulcers. However, there are only a handful of reports addressing the pain management of PV.^3–5

We would like to present a case of a painful PV, which was successfully managed.

Case presentation

A man in his 30s was presented to the hospital with sudden onset of blisters in his oral cavity and skin. He was admitted to the hospital after failure of over-the-counter medication to help him with the pain. He described his pain as burning and stabbing in nature.

On admission, his pain score was 10 over 10, with painful ulcers seen in his oral cavity and erosions over his body, especially over his neck and back (figure 1). The pain increased on movement and was partially relieved by medication. The patient described his pain as burning in nature, radiating to both upper limbs.

Figure 1.

Erosions with crusting seen over back, face and neck.

Investigations

A full blood count, liver function test and a renal function test showed a normal result.

Differential diagnosis

Pain secondary to pemphigus vulgaris.

Treatment

On admission, he was started on morphine infusion at 3 mg per hour, after an initial bolus dose of 5 mg. The patient was also started on acetaminophen 1 gm four times a day. However, the pain was not relieved. He was then referred to the pain service unit.

After a comprehensive review, the patient was started on oral gabapentin 300 mg daily, which was increased gradually to 300 mg three times a day. His pain improved after 3 days on gabapentin. The morphine infusion was titrated down and stopped after 1 week of gabapentin.

Outcome and follow-up

After 2 months of medication, his gabapentin dosage was reduced gradually. The patient is currently pain-free.

Discussion

PV is the major form of pemphigus. The incidence of PV is around 0.1–0.5/100 000 population.^{6 7} The average age of onset for PV is usually at 4th and 5th decades. There have been several documented triggers for PV. These include infections (Herpes Simplex virus, Epstein-Barr virus), drugs (captopril, penicillamine), ultra-violet radiation (UVR), pesticides, ionising radiation, stress, thermal burns and food containing allium, phenol, thiol or urushiol.^{8 9}

The hallmark of PV is mucosal involvement with painful blisters and erosions. This is seen commonly in the oropharyngeal mucous involvement.¹⁰ Although PV usually presents in the oral cavity, other sites can be involved. PV involves two main subgroups (table 1).

Table 1.

Subgroups of pemphigus vulgaris

Mucosal dominant type	Mucocutaneous type
Mucosal erosions Minimal skin involvement	Diffuse mucosal involvement Cutaneous blisters and erosions

Cutaneous lesions of PVtypically present with flaccid blisters and crusted erosions, with an erythematous base.¹¹

Systemic corticosteroids and immune-suppressants remain the gold standard of the management of a pemphigus therapy.¹² However, long-term systemic corticosteroid therapy is associated with an increased incidence of serious adverse events.¹³ The main cause of pain in PV patients is due to the epithelium disruption. Therefore, wound dressing will be helpful in pain management. Wound dressings will not only reduce fluid and evaporative losses, but also provide a bacteriological barrier and confers protection from mechanical trauma. This will improve pain control.¹⁴

In patients with PV, the neural pathways are activated through primary afferent sensory fibres, primarily by myelinated A-delta fibres and unmyelinated C fibres. For pain management, the WHO has suggested oral morphine for patients with severe pain (VAS – 7–10).¹⁵ The morphine should be titrated to achieve an ideal pain score of 4 over 10. Oral administration of neuromodulators, including pregabalin and gabapentin, is also used, but these drugs can only achieve therapeutic concentrations after 2–3 weeks of continuous administration.¹⁴ Several studies have shown that reduction in the pain score of 30%–40% is required to show a significant reduction in the pain score.

Our patient presented with symptoms of neuropathic pain, which warrants a neuropathic medication. This is often missed when managing a patient with PV. With the administration of oral gabapentin, our patient had a significant improvement in pain management.

Learning points.

• For the comfort of the patient, pain management should be multidisciplinary.

• A proper pain assessment and treatment adjustments are very important for a successful management of pemphigus vulgaris (PV).

• A rapid diagnosis and quick response to the pain management of patients with PV is of utmost importance for the comfort of the patient.

Ethics statements

Patient consent for publication

Consent obtained directly from patient(s).