| 0.5mm \(\mathrm{TFN - \alpha}\) inhibitors. Rituximab is off-label and used for various autoimmune disorders including, PV due to potential therapeutic effects in the modulation of pathogenic B cells [5]. We report a case of generalized PV, treated with rituximab. | |
| ## Case presentation | |
| A 39- year- old male patient who lives in Surat, Gujarat, was referred with a 3- month history of painful ulcerated lesions in the oral cavity. On enquiring about the patient's history, we came to know that initially, the patient had difficulty chewing food and the severity increased gradually. The ulcerations caused considerable discomfort, affecting his normal oral functions. Subsequently, fluid- filled lesions developed involving the scalp, trunk, limbs, and axilla. Lesions were increasing in size and number and had little tendency to heal. Blisters were flaccid and burst on their own to form erosions within 2- 3 days. Medical and family history was non- contributory. No history of fever, joint pain, malaise, and photosensitivity. He had weak oral hygiene due to the bad habit of taking betel quid with tobacco five times a day and smoking seven- bidi per day for the past 12 years. Further, he consumes two- quarters of alcohol on an alternative day for the last 12 years. History of any drug intake before the appearance of lesions was also absent. Intraoral examination revealed that approximately \(1.0 \times 1.5\) dimensions ulceration lesions were present on the buccal mucosa. Dermatological examination revealed multiple vesicular lesions ranging from \(0.3 \times 0.3\) to \(1.5 \times 1.5\) involving the face, trunk, upper limbs, and dorsum of the penis (Figure 1a- i). | |
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| <center>Figure 1: Showing (a) ulcerative lesions present on the buccal mucosa (b) multiple vesicular lesions present on the face (c) multiple vesicular lesions with erosion present on the lower neck (d) multiple vesicular lesions present on the umbilicus (e) multiple vesicular lesions with erosion present on the upper limb (f) multiple vesicular lesions with erosion present on the back (g) multiple vesicular lesions with erosion on the axilla (h) flaccid blister lesions on the scalp (i) multiple vesicular lesions present on the dorsum of the penis. </center> | |
| There was a positive Nikolsky sign and a bulla spread sign. The clinical manifestations of oral ulcers, flaccid bullae, and positive Nikolsky sign hinted at the provisional diagnosis of PV. Mucous membrane pemphigoid, bullous lichen planus, paraneoplastic pemphigus, chronic ulcerative stomatitis, recurrent herpes lesions in immunocompromised patients, and erythema multiforme were the potential differential diagnosis of this condition. Regarding this, a biopsy was performed from a new vesicle to confirm the diagnosis. Histopathological examination revealed an intraepidermal supraslab acantholytic blister. Several acantholytic cells and neutrophils could be seen in the blister. The floor of the blister showed a tombstone pattern with occasional acantholytic cells. A moderately dense superficial perivascular mixed infiltrate was present in the dermis. Mild spongiosis with neutrophils was present at the periphery of the blister (Figure 2). | |
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| <center>Figure 2: Photomicrograph showing acantholysis of the keratinocytes, tombstone appearance, epithelium exhibiting spongiosis, and superficial perivascular mixed infiltrate (H & E stain, ×5). </center> | |
| The hematological test had all findings within standard limits and, routine urine examination was unremarkable. In accordance with these findings, the definite diagnosis of PV was made and the treatment with oral cefuroxime (500mg twice a day) and oral prednisolone (20mg twice a day) with azathioprine (50mg twice a day) was started. Topical antibiotics and triamcinolone gel are advised for local application in the oral cavity. The dose of oral prednisolone was gradually tapered to 20mg, 10mg, 5mg, and 2.5mg (twice a day) every 30 days. The patient was maintained on the same dose of azathioprine (50mg twice a day) for one year. With the given therapy, complete remission was not achieved. Also, azathioprine was discontinued due to an elevated level of liver enzymes. Hence, the patient was shifted to rituximab therapy. The patient was initially given three doses of rituximab 1 gm each on days 1, 15, and 45. As premedication, ceftriaxone 1gm intravenously, hydrocortisone 100mg intravenously, paracetamol 650mg stat orally, and pheniramine maleate 2cc stat intravenously were given, sequentially on the day of infusion. After 30 minutes of these premedications rituximab (1gm) intravenously in 500ml of normal saline was given slowly over six to eight hours. The last dosage of rituximab was given after 3 months. A administration of rituximab lead to decrease Dsg 3 antibody levels which in turn resulted in the complete remission of the skin lesions within the next year (Figure 3a- g). |