Rare autoimmune blistering disease in an elderly man controlled by mycophenolate mofetil and prednisolone

A 73-year-old Japanese man whose eyes, nose and skin were being progressively destroyed by his own immune system has made a full recovery on a drug combination rarely used for his form of the disease, according to a case report published in the Journal of Cutaneous Immunology and Allergy. The patient suffered from anti-laminin 332-type mucous membrane pemphigoid, a rare autoimmune blistering disorder in which antibodies attack proteins that glue the skin’s surface layers to the underlying tissue. Within four months of starting mycophenolate mofetil together with the corticosteroid prednisolone, every mucosal and skin lesion had healed, and laboratory tests showed that the culprit antibodies had vanished from his blood.

Mucous membrane pemphigoid, often abbreviated MMP, is an umbrella term for a family of autoimmune diseases that target the basement membrane zone, the thin sheet of proteins that anchors the epithelial cells of mucous membranes and skin to the connective tissue beneath. When the immune system produces antibodies against components of this anchoring complex, the attachment fails, fluid accumulates between the layers, and painful blisters and erosions form. In MMP the damage is concentrated in the wet linings of the body: the mouth, eyes, nose, throat, esophagus and genitals. Because these tissues scar as they heal, repeated cycles of blistering and repair can gradually fuse the eyelids to the eyeball, narrow the airway, or seal off the esophagus, which is why untreated MMP can cause blindness or become life-threatening.

Physicians classify MMP patients by risk. Those with lesions confined to the mouth are considered low risk, while patients whose disease strikes the eyes, nasopharynx, larynx, esophagus or genitals, particularly when lesions progress rapidly, are classed as high risk and face the greatest threat of permanent structural damage. Current treatment guidelines recommend high-dose prednisolone combined with potent immunosuppressants such as cyclophosphamide or azathioprine for these high-risk patients. These regimens can work, but they carry a heavy burden of side effects, a serious concern in elderly patients who already tolerate strong drugs poorly.

Approximately one quarter of MMP patients produce antibodies against laminin 332, a large cross-shaped molecule of the basement membrane built from three protein chains designated alpha, beta and gamma. Recognizing this antibody specificity matters for two reasons. First, anti-laminin 332-type disease has a documented association with underlying malignancies, so identifying the antibody profile prompts a search for cancer. Second, the precise target may influence how the disease behaves and how it responds to therapy. In the reported case, the clinical team found no tumors on computed tomography scans or on endoscopic examination of the upper and lower digestive tract, confirming a non-paraneoplastic form of the disease.

The diagnostic journey began when the man sought care for erosions of the nasopharyngeal and ocular mucous membranes that had been worsening for three months. Vesicles surrounded by red, inflamed skin then appeared on his trunk and limbs. A biopsy of an abdominal lesion showed a subepidermal blister, a split beneath the outermost skin layer, packed with eosinophils, lymphocytes and histiocytes, the characteristic inflammatory signature of pemphigoid disease. A biopsy of the nasal septum revealed granulation tissue with extensive inflammation, reflecting the destructive remodeling underway in the mucosa. Direct immunofluorescence, a technique that visualizes antibodies deposited in the patient’s own tissue, displayed linear ribbons of IgG and the complement protein C3 along the basement membrane zone.

To pinpoint the exact antigen, the researchers applied a battery of immunological tests. Screening immunoassays for BP180, BP230, type VII collagen and the desmogleins, proteins targeted in other blistering diseases, all came back negative. Indirect immunofluorescence on salt-split normal human skin, a classic trick that separates the epidermis from the dermis so that the binding side of an antibody reveals its target, showed the patient’s IgG attaching to the dermal side of the split, a pattern pointing toward the lamina lucida proteins rather than the hemidesmosomal components above them. Immunoblotting with recombinant laminin 332 fragments then detected IgG against the 165-kilodalton laminin alpha 3 chain, and immunoblotting with a hemidesmosome-rich extract confirmed reactivity with the 200-kilodalton form of laminin alpha 3 while ruling out integrin beta 4, another possible MMP antigen. The diagnosis of anti-laminin 332-type MMP was secure.

Severity was quantified with the mucous membrane pemphigoid disease area index, a scoring system that tracks disease activity and accumulated damage across the skin, scalp and mucous membranes. The patient’s initial total activity score stood at 130, with 90 points contributed by mucosal lesions, and his total damage score was 18. Treatment began with mycophenolate mofetil at 2000 milligrams per day, an immunosuppressant that inhibits an enzyme required for proliferating lymphocytes, combined with oral prednisolone at 1.0 milligram per kilogram of body weight per day. The response was rapid and complete. Within four months all lesions had resolved, the disease area index fell to negative values, and five months after treatment began, immunoblotting could no longer detect the anti-laminin 332 antibodies in his serum, indicating that the autoimmune attack itself had been switched off rather than merely masked.

The authors argue that mycophenolate mofetil deserves a larger role in anti-laminin 332-type MMP, especially when the eyes are involved. Previous studies have reported success with the drug in ocular cicatricial pemphigoid, including a series of 38 patients treated at a single center, and the drug’s side-effect profile is generally milder than that of cyclophosphamide and other intensive immunosuppressants. For an elderly patient, whose reserves for tolerating aggressive chemotherapy-like regimens are limited, a steroid-sparing agent that controls disease with fewer complications is clinically valuable. The present case adds weight to that argument by demonstrating both clinical remission and serological clearance of the pathogenic antibodies.

At the same time, the authors are careful about the limits of a single case. Anti-laminin 332-type MMP is rare, and specific data on mycophenolate mofetil use in elderly patients remain scarce, so the report cannot establish the drug’s safety and efficacy across a population. What it does provide is a detailed, antibody-verified template: a high-risk elderly patient with ocular and nasopharyngeal disease, a malignancy workup that came back clean, a molecularly precise diagnosis, and a full remission achieved on a relatively gentle two-drug regimen. For clinicians confronting similar cases, the report suggests that mycophenolate mofetil plus prednisolone can be an effective alternative when standard agents are unsuitable.

For patients and their families, the case carries a simpler message. Autoimmune blistering diseases of the mucous membranes are rare, but they are diagnosable with modern immunological tools and treatable when caught early. Persistent mouth sores, unexplained eye redness and scarring, or recurring blisters on the nose and throat warrant evaluation by specialists familiar with immunobullous disease, because the window for preventing permanent scarring closes with each new lesion. The Japanese team’s experience shows that even in a 73-year-old with disease already threatening the eyes, early recognition of the antibody target and prompt combination therapy can restore the mucous membranes to health and silence the autoimmune attack at its source.

Subject of Research: A case of anti-laminin 332-type mucous membrane pemphigoid with ocular symptoms successfully treated with mycophenolate mofetil and prednisolone in an elderly man

Article Title: A case of anti-laminin 332-type mucous membrane pemphigoid with ocular symptoms successfully treated with mycophenolate mofetil and prednisolone in an elderly man

Article References: Fukumitsu, S., Hashimoto, T., Matsumoto, Y., Nagai, T., Iritani, K., Hirako, Y., Kubo, A., & Fukumoto, T. (2026). A case of anti-laminin 332-type mucous membrane pemphigoid with ocular symptoms successfully treated with mycophenolate mofetil and prednisolone in an elderly man. Journal of Cutaneous Immunology and Allergy, 9, Article 16615. https://doi.org/10.3389/jcia.2026.16615

Image Credits: AI Generated

DOI: 10.3389/jcia.2026.16615

Keywords: case, anti-laminin, type, mucous, membrane, pemphigoid, ocular, symptoms, successfully, treated, mycophenolate, mofetil