Waranaree WinayanuwattikunLeena ChularojanamontriPapapit TuchindaPenvadee PattanaprichakulKanokvalai KulthananFaculty of Medicine, Siriraj Hospital, Mahidol University2019-08-282019-08-282018-01-01Siriraj Medical Journal. Vol.70, No.6 (2018), 523-528222880822-s2.0-85059518856https://repository.li.mahidol.ac.th/handle/20.500.14594/47045© 2018 Siriraj Medical Journal. Objective: To report a case of paraneoplastic pemphigus (PNP), a rare disease, associated with follicular B-cell lymphoma. Treatment outcomes of PNP associated with follicular B-cell lymphoma following rituximab treatment were also reviewed in this article. Case presentation: We reported a PNP patient presenting with intractable stomatitis and erythema multiforme-like lesions. Skin biopsy from erythema multiforme-liked lesion revealed interface dermatitis and necrotic keratinocytes. Direct immunofluorescence demonstrated immunoglobulin G deposition at intercellular space, as well as complement deposition at dermo-epidermal junction. Indirect immunofluorescence using rat bladder substrate was helpful in confirming the diagnosis of PNP. Further investigations revealed an underlying disease of follicular B-cell lymphoma. He was treated with rituximab and systemic corticosteroids. Improvement of mucocutaneous lesions and lymphoma were noted. Nevertheless, he developed hospital-acquired pneumonia and died from septic shock shortly after receiving conventional chemotherapy. His survival duration was approximately 8 months after diagnosis of PNP. Conclusion: It seemed that rituximab might provide promising benefits for mucocutaneous lesions in PNP patients associated with follicular B-cell lymphoma.Mahidol UniversityMedicineArticleSCOPUS10.14456/smj.2018.84