You JY, et al. - Researchers conducted this retrospective case series to describe the clinical characteristics of patients with direct immunofluorescence (DIF)-negative mucus membrane pemphigoid (MMP). The study sample consisted of 36 patients who had a conjunctival biopsy for suspected MMP. Data reported that 32 patients had a negative DIF. Of those, two had a positive DIF on repeat biopsy. In the lack of alternative diagnoses, patients with progressive cicatrizing conjunctivitis may have MMP. The results highlight that MMP suspicion must stay high for patients with Foster stage 3 conjunctival scarring on the presentation or worsening of scarring during follow-up, even in setting negative DIF.