Oral mucous membrane pemphigoid: updates in diagnosis and management.

Mucous membrane pemphigoid (MMP) is a rare, immune-mediated, vesiculobullous disease that predominantly affects the oral cavity and conjunctiva. In MMP, autoantibodies are directed against hemidesmosomal proteins in the basement membrane zone, most commonly BP180. Clinical signs and symptoms include gingival desquamation, erosions, and ulcerations. Differential diagnoses include other immune-mediated blistering diseases, such as bullous pemphigoid. Definitive diagnosis is reached through history taking, physical examination, tissue biopsy and/or serology testing. MMP, although not curable, is typically managed with topical or systemic corticosteroids, in addition to immunosuppressive therapies and biologic agents in recalcitrant cases. Untreated MMP can lead to life-threatening complications, such as blindness. As a condition that affects the oral cavity, it is important that dentists understand how to recognise, diagnose and manage the disease.

Ocular cicatricial pemphigoid: is there an association with autoimmune diseases?

PURPOSE: To assess the prevalence of autoimmune diseases (ADs) associated with ocular cicatricial pemphigoid (OCP) and analyze clinical, laboratory, and treatment associations between these entities. METHODS: A multicentre cross-sectional study of patients with an OCP diagnosis. The population was divided into two groups according to their association with other ADs or not. Clinical, laboratory and treatment variables were described and compared between groups. A multivariable logistic regression analysis was performed to identify variables that could suggest the association between OCP and ADs. RESULTS: Eighty-eight patients were recruited, with a mean age at diagnosis of 64.3 years (SD 11.9). Biopsy was performed in 86.8% of the patients. There was a median delay of 2 years from the onset of symptoms to diagnosis. Extraocular involvement was evidenced in 11.5%. The group associated with ADs included 24 patients (27.3%). The most prevalent diagnosis was Sjögren´s syndrome. Hypergammaglobulinemia was associated with ADs and OCP, adjusted for age, sex, smoking, skin and mucosal involvement, and erythrocyte sedimentation rate (OR 8.7; 95%CI 1.6-46.8; p = 0.012). CONCLUSIONS: Due to OCP's autoimmune nature, it could coexist with other ADs. This study observed that more than a quarter of the population presented with this association, and hypergammaglobulinemia could suggest it.

Survey: Preferred practice patterns in the diagnosis of mucous membrane pemphigoid amongst cornea specialists.

PURPOSE: To evaluate preferred diagnostic tools and treatment decision-making factors in cases suspicious of mucous membrane pemphigoid (MMP) amongst ophthalmologists and cornea specialists. METHODS: Web-based survey, consisting of 14 multiple choice questions, posted to the Cornea Society Listserv Keranet, the Canadian Ophthalmological Society Cornea Listserv, and the Bowman Club Listserv. RESULTS: One hundred and thirty-eight ophthalmologists participated in the survey. Eighty-six percent (86%) of respondents were cornea trained and practiced in either North America or Europe (83%). Most respondents (72%) routinely perform conjunctival biopsies for all suspicious cases of MMP. For those who do not, fear that biopsy will exacerbate inflammation was the most common reason to defer investigation (47%). Seventy-one percent (71%) performed biopsies from perilesional sites. Ninety-seven percent (97%) ask for direct (DIF) studies and 60% for histopathology in formalin. Most do not recommend biopsy at other non-ocular sites (75%), nor do they perform indirect immunofluorescence for serum autoantibodies (68%). Immune-modulatory therapy is started following positive biopsy results for most (66%), albeit most (62%) would not let a negative DIF influence the choice of starting treatment should there be clinical suspicion of MMP. Differences in practice patterns as they relate to level of experience and geographical location are contrasted to the most up-to-date available guidelines. CONCLUSION: Responses to the survey suggest that there is heterogeneity in certain practice patterns for MMP. Biopsy remains an area of controversy in dictating treatment plans. Identified areas of need should be targeted in future research.

Direct Immunofluorescence Findings and Factors Affecting Conjunctival Biopsy Positivity in Ocular Mucous Membrane Pemphigoid.

PURPOSE: The aim of this study was to describe the direct immunofluorescence (DIF) findings and factors affecting conjunctival biopsy positivity in patients clinically diagnosed with ocular mucous membrane pemphigoid (OMMP). METHODS: This retrospective observational case series included patients with clinical OMMP who underwent conjunctival biopsy for DIF in at least 1 eye between 2018 and 2021 in an institutional setting. The primary outcome measures were association of age and chronic ocular complications with biopsy positivity. RESULTS: Of 61 patients, DIF positivity was seen in 33 (54.1%) clinically suspected cases of OMMP. Of 39 patients who underwent bilateral biopsy, 23 (59%) were positive, of which 12 (52%) were positive in both eyes while 11 (48%) were positive in 1 eye. Of 22 patients who underwent unilateral biopsy, 10 (45%) were positive. Of the 100 biopsied eyes, 45 (45%) were DIF positive. Among the immunoreactants studied, linear deposition of C3 was seen in all 45 positive eyes (100%). Increasing age was significantly associated with higher likelihood of biopsy negativity ( P = 0.032), whereas a greater Sotozono chronic ocular complication score, indicative of disease severity, was associated with low likelihood of biopsy positivity ( P = 0.0042) and lower overall expression of immunoreactants on DIF ( P = 0.0007). CONCLUSIONS: Older patients and patients with more severe ocular surface disease sequelae are likely to have negative DIF results. To optimize the chances of confirming the diagnosis of OMMP by DIF, both eyes should be biopsied early in the disease course. If 1 eye is being biopsied, the less affected eye must be chosen.

Concurrence of Ocular Cicatricial Pemphigoid in Chronic Ocular Graft-Versus-Host Disease.

PURPOSE: The aim of this study was to report a series of 3 patients with ocular graft-versus-host disease (oGVHD) with progressive cicatricial conjunctival changes who were diagnosed with ocular cicatricial pemphigoid (OCP) after conjunctival biopsy. METHODS: This study was a retrospective case series. RESULTS: Three patients who received hematopoietic stem cell transplantation for hematologic malignancies developed oGVHD and subsequently were diagnosed with OCP. Case 1 was a 73-year-old woman with oGVHD who developed symblepharon and showed positive IgA, IgG, and C3 staining of the basement membrane zone (BMZ) on conjunctival biopsy, consistent with OCP. She was systemically treated with tacrolimus and prednisone with resolution of conjunctival inflammation. Case 2 was a 68-year-old man with oGVHD who developed symblepharon, severe dry eye, and corneal epithelial defect. An initial conjunctival biopsy was negative, but a repeat biopsy performed 10 years later showed positive BMZ IgA and IgG staining. Healing of the epithelial defect was achieved after treatment with high-dose systemic cyclosporine. Case 3 was a 75-year-old woman with oGVHD who had a nonhealing corneal epithelial defect and symblepharon with positive IgA BMZ staining on conjunctival biopsy, consistent with OCP. The patient responded well to methotrexate with healing of the epithelial defect. CONCLUSIONS: Although low-grade conjunctival fibrotic changes may be observed in chronic oGVHD, development of severe and progressive cicatricial changes, including symblepharon formation, should prompt consideration of biopsy to rule out concurrent OCP, the management of which differs from that of oGVHD.

Tissue Remodeling in Ocular Mucous Membrane Pemphigoid.

Purpose: Ocular mucous membrane pemphigoid (OcMMP) is a rare eye disease characterized by relapsing-remitting or persisting long-lasting inflammatory events associated with progressive scarring. Despite long-term immunomodulating therapy, abnormal fibrosis keeps worsening in patients with OcMMP. This study investigates the fibrotic process in patients with OcMMP, as well as the critical role of the epithelium in modulating the local fibrosis. Methods: In this prospective, observational pilot study, patients affected by long-lasting OcMMP were compared with age- and gender-matched healthy controls. Clinical grading was assessed, and conjunctival biopsy and impression cytology were performed. Conjunctival samples were used for quantifying the expression of transcripts regulating the inflammatory and fibrogenic processes. Results: Ocular surface clinical and functional markers worsened in patients with OcMMP with fibrotic disease progression. In more advanced disease stages, both impression cytologies and conjunctival biopsies revealed increased tissue remodeling and profibrotic markers (α-SMA and TGF-ß), and decreased levels of inflammatory markers (I-CAM1, IL-10, and IL-17). Increased epithelial expression of profibrotic markers and histological changes were detected. Conclusions: Chronic OcMMP is characterized by a progressive, aberrant self-sustaining fibrotic process that worsens clinical signs and symptoms. Conjunctival epithelial cells may transdifferentiate into myofibroblast-like phenotypes when chronically exposed to high levels of inflammation, as in the case of OcMMP. Tissue remodeling markers in OcMMP could be used as early diagnostic, prognostic, and therapeutic biomarkers, harvested in a non-invasive and painless procedure such as impression cytologies.

[Pemphigoid diseases in older adults]. / Pemphigoiderkrankungen bei älteren Menschen.

Pemphigoid diseases are a group of bullous autoimmune diseases characterized by autoantibodies against structural proteins of the dermal-epidermal junction. With a steadily growing aging population, pemphigoid diseases are emerging as a significant medical challenge, because they occur primarily in older individuals. The by far most common disease is bullous pemphigoid, which is clinically characterized by tense blisters, erosions, erythema or urticarial plaques, while severe pruritus is the leading subjective symptom. Mucous membrane pemphigoid predominantly affects surface-close mucous membranes with painful erosions and blisters as well as frequently scarring usually in the mouth, nose, and eyes. Anti-p200 pemphigoid clinically resembles bullous pemphigoid but is much less common. Diagnosis of these diseases involves the combination of clinical evaluation, lesional histopathology, direct immunofluorescence microscopy of a perilesional biopsy and serology. Topical and systemic corticosteroids are the mainstay of pemphigoid diseases treatment. Depending on the severity of the disease, various potentially corticosteroid-sparing therapies, such as dapsone, doxycycline, methotrexate, azathioprine and mycophenolate may be used. In severe courses, treatment with rituximab, cyclophosphamide, intravenous immunoglobulins or immunoadsorption are second- or third-line treatment options. Patients are best managed in centers experience with the management of pemphigoid diseases. Updated national and international guidelines for the diagnosis and treatment of bullous pemphigoid and mucous membrane pemphigoid have recently been published.

Evaluation of the Diagnostic Value of Oesophageal Biopsies for Direct Immunofluorescence Microscopy in Mucous Membrane Pemphigoid.

Mucous membrane pemphigoid is an autoimmune blistering disorder characterized by predominant involvement of surface-close epithelia and linear depositions of immunoreactants at the dermal-epithelial junction on direct immunofluorescence microscopy. A major diagnostic difficulty is the frequent need for multiple biopsies to facilitate the diagnosis. Although oesophageal involvement is a rare, but life-threatening manifestation, the relevance of oesophageal direct immunofluorescence sampling is unclear. This retrospective monocentric study evaluated 67 non-lesional biopsies from 11 patients with mucous membrane pemphigoid and clinical symptoms suggestive of oesophageal involvement, comprising 31 samples from the oesophagus and 36 samples from other anatomical sites. Five patients (45.5%) exhibited endoscopic findings compatible with oesophageal involvement of mucous membrane pemphigoid. No correlation was identified between the presence of oesophageal lesions and direct immunofluorescence positivity in lesions from the oesophagus (p = 1.0). Oral and cutaneous samples were significantly more frequently positive by direct immunofluorescence than were oesophageal biopsies (p < 0.0001 and p = 0.0195, respectively). Oesophageal samples yielded significantly less IgG reactivity than oral and cutaneous lesions (p < 0.0001 and p = 0.0126, respectively), and less IgA antibody response than oral lesions (p = 0.0036). In conclusion, oesophageal direct immunofluorescence samples were inferior to oral and cutaneous biopsies for the diagnosis of mucous membrane pemphigoid even when oesophageal lesions compatible with mucous membrane pemphigoid were present at the time of biopsy.

Ocular involvement in autoimmune bullous diseases.

Autoimmune bullous diseases represent a heterogenous group of disorders caused by autoantibodies against adhesion molecules; the location of the target protein determines the level of cleft formation. The spectrum of ocular lesions in autoimmune bullous diseases can range from mild symptoms to severe involvement with sight impairment and even, in some cases, blindness. In pemphigus vulgaris, the prevalence of ocular involvement has been reported to be between 7% and 26%. The most common clinical sign of ocular pemphigus vulgaris is bilateral conjunctivitis with hyperemia. Ocular involvement also occurs in 41% to 70% of patients with paraneoplastic pemphigus. The main ocular manifestations are bilateral cicatrizing conjunctivitis with symblepharon formation, and shortening of the fornices. In mucous membrane pemphigoid, ocular involvement is seen in 61% to 70% of patients; the most frequent ocular finding is cicatricial conjunctivitis. Patients with autoimmune bullous diseases having common ocular involvement should be assessed by an ophthalmologist to avoid serious complications. Diagnostic procedures and treatment require multidisciplinary care based on the close cooperation between dermatologists and ophthalmologists.

Vortex Keratopathy as a Presenting Feature of Ocular Mucous Membrane Pemphigoid.

PURPOSE: The aim of this study was to describe the presenting feature of vortex keratopathy in 3 patients with biopsy-proven ocular mucous membrane pemphigoid (OMMP). METHODS: The first patient was a 52-year-old woman with chronic redness and foreign body sensation for 3 years who presented with unilateral vortex keratopathy. Seven months later, in the same eye, she developed conjunctival signs suggestive of OMMP. The second patient was a 33-year-old woman with similar chronic symptoms that were exacerbated by pterygium surgery. Clinical examination revealed vortex keratopathy in the right eye with subtle conjunctival signs suggestive of OMMP. The third patient was a 70-year-old woman with complaints of repeated episodes of redness and foreign body sensation for 18 months who presented with vortex keratopathy in the right eye and conjunctival signs suggestive of OMMP in the same eye. To confirm the clinical diagnosis, bilateral conjunctival biopsy was performed in all patients. RESULTS: OMMP was diagnosed based on conjunctival signs and confirmed on direct immunofluorescence positivity, demonstrating antibodies characteristic and diagnostic of OMMP in the basement membrane zone. A unique feature that preceded or coexisted with the conjunctival signs was unilateral vortex keratopathy seen in all 3 patients, independent of the stage of the disease at which they presented. CONCLUSIONS: Vortex keratopathy can be a presenting feature in patients with OMMP. A complete ocular surface examination, especially checking the medial canthus for keratin and the inferior fornix for foreshortening, is necessary. Conjunctival biopsy should be performed in all cases to confirm the clinical diagnosis wherever required.

[Diagnostics of ocular mucous membrane pemphigoid]. / Diagnostik des okulären Schleimhautpemphigoids.

The diagnosis of ocular mucous membrane pemphigoid (MMP) remains a challenge as the timing and choice of diagnostic methods have a decisive influence on its quality. A systematic approach is required that includes a comprehensive medical history, critical evaluation of the clinical findings and targeted laboratory testing. The diagnosis is complicated by the fact that some patients present purely clinically the symptoms of MMP without fulfilling the required immunohistochemical and laboratory criteria. Basically, the diagnosis of ocular MMP is based on three pillars: 1) medical history and clinical findings, 2) positive immunohistological (direct immunofluorescence) tissue sample and 3) specific serological autoantibodies. As the diagnosis of ocular MMP often implies prolonged systemic immunomodulatory treatment in predominantly older patients, the accurate diagnosis and approach are of critical relevance. The aim of this article is to present the recently updated diagnostic procedure.

[Treatment of ocular mucous membrane pemphigoid]. / Therapie des okulären Schleimhautpemphigoids.

Ocular mucous membrane pemphigoid is the manifestation of a systemic autoimmune disease. As autoantibodies circulating in the blood cannot be adequately treated by eye drops, systemic immunosuppressive treatment of this autoimmune disease naturally plays the most important role. Ophthalmic topical or even surgical procedures are only used as supportive measures or usually to control ocular complications that have developed. Patients with the typical clinical picture are treated causally with systemic immunosuppression causally, nurturing eye drops, as well as by minimally invasive surgery if complications arise, if possible in an inflammation-free state, in accordance with the guidelines if the diagnosis is positive but also if the biopsy and serology are repeatedly negative after exclusion of all differential diagnoses. Purely topical anti-inflammatory treatment is insufficient to prevent irreversible progression of scarring conjunctivitis. Corresponding treatment recommendations have been formulated in current European as well as German guidelines and are presented here as an overview.

Clinical Approach to Ocular Cicatricial Pemphigoid.

Objectives: To evaluate the demographic data, ocular and systemic findings, clinical management, and outcomes of patients with ocular cicatricial pemphigoid (OCP). Materials and Methods: The medical records of 11 patients diagnosed as having OCP in the ophthalmology department of Ege University between 2008 and 2021 were evaluated retrospectively. Results: The patients' mean follow-up time was 14±5.76 months. All eyes (100%) had conjunctival involvement and 18 (81.81%) had corneal involvement. According to the Tauber staging system, 7 (31.81%), 8 (36.36%), and 7 (31.81%) of the eyes were stage 2, 3, and 4, respectively. The diagnosis was confirmed in 6 (66.66%) of 9 patients who underwent biopsy. Amniotic membrane transplantation was performed in 7 eyes, entropion surgery in 2 eyes, and electrocauterization for trichiasis in 5 eyes. Systemic involvement was observed in 45.45% (5/11) of patients, most commonly oral mucosal involvement (18.18%). Review of medical records showed that alkylating agents, steroids, and dapsone were used in patients treated before 2020. Mycophenolate mofetil was preferred to be used in combination with corticosteroids. Although treatment responses before mycophenolate mofetil usage could not be evaluated well because of loss to follow-up, 4 (66.66%) of 6 patients who received steroid treatment combined with mycophenolate mofetil showed partial or complete clinical remission. No serious side effects and drug withdrawal were observed. Conclusion: OCP is a sight-threatening autoimmune disease that affects older adults. Although positive biopsy results are valuable for diagnosis, negative results do not exclude the diagnosis. The main treatment is systemic immunosuppressives. Disease activity can be suppressed, especially with early initiation of drug therapy. These patients require a multidisciplinary approach. Especially in the presence of isolated ocular findings, ophthalmologists should be able to make the decision to start immunosuppressive treatment, and systemic treatment should not be delayed.

Vesiculobullous Lesions of the Oral Cavity.

Several dermatological conditions may manifest in the oral cavity, particularly those that are immune-mediated, and they must be distinguished from the various other types of oral ulcerations. This chapter discusses the clinical features, pathogenesis, differential diagnosis, and diagnostic features, including histology and immunofluorescence findings, as well as management of vesiculobullous diseases. These diseases include pemphigus Vulgaris, benign mucous membrane pemphigoid, bullous pemphigoid, and epidermolysis bullosa acquisita. These diseases have a significant impact on the quality of life, as they can lead to serious complications, depending on the extent of the disease. Therefore, early recognition is crucial, helping to reduce disease-related morbidity, mortality and prevent life-threatening complications.

Disease Endotypes Predict the Severity of Mucous Membrane Pemphigoid.

Mucous membrane pemphigoid is an autoimmune disease with variable clinical presentation and multiple autoantigens. To determine whether disease endotypes could be identified on the basis of the pattern of serum reactivity, the clinical and diagnostic information of 70 patients with mucous membrane pemphigoid was collected, and reactivity to dermal or epidermal antigens, using indirect immunofluorescence, and specific reactivity to bullous pemphigoid (BP) autoantigens BP180 and BP230, collagen VII, and laminin 332 were evaluated. Most patients had lesions at multiple mucosae, with the most prevalent being oropharyngeal (mouth, gingiva, pharynx; 98.6%), followed by ocular (38.6%), nasal (32.9%), genital or anal (31.4%), laryngeal (20%), and esophageal (2.9%) sites and skin (45.7%). Autoantigen profiling identified BP180 (71%) as the most common autoantigen, followed by laminin 332 (21.7%), collagen VII (13%), and BP230 IgG (11.6%). Reactivity to dermal antigens predicted a more severe disease characterized by a higher number of total sites involved, especially high-risk sites, and a decreased response to rituximab. In most cases, identification of dermal indirect immunofluorescence reactivity is an accurate predictor of disease course; however, confirmation of laminin 332 reactivity is important, with dermal indirect immunofluorescence positivity because of an increased risk of solid tumors. In addition, the ocular mucosae should be monitored in patients with IgA on direct immunofluorescence.

MicroPulse Transscleral Laser Therapy in Patients With Glaucoma and Ocular Cicatricial Pemphigoid.

A non-comparative retrospective case-series study was performed on 6 patients (12 eyes) with a confirmed diagnosis of ocular cicatricial pemphigoid (OCP), treated with MicroPulse Transscleral Laser Therapy (MP-TLT), between January 2018 and 2020, with a minimum follow-up of 2 years, in a private ophthalmology practice with offices in Argentina and Colombia. Mean age was 75±6.3 years (66-83 yrs). The severity of ocular cicatricial pemphigoid remained stable 2 years after MP-TLT. Baseline mean IOP was 19.5±5.9 mmHg (13-30 mmHg) and, 24 months after treatment, IOP decreased to a mean of 13.9±1.9 mmHg (10-18 mmHg). The mean IOP reduction was 25.1% ( P : 0.002). The mean number of anti-glaucomatous drugs at baseline was 3.1±0.7, decreasing to 0.6±0.7, 2 years after MP-TLT ( P <0.001). MP-TLT may be considered as a non-incisional approach to glaucoma care for patients with ocular surface diseases, prospective long term studies are needed.

Radiation-Induced Laryngeal Mucous Membrane Pemphigoid.

OBJECTIVES: Bullous pemphigoid has previously been linked to radiotherapy, but here we report the first case of MMP suspected to be a consequence of RT. METHODS: The patient described is an 85-year-old male who underwent RT to treat squamous cell carcinoma of the palatine tonsil. Shortly after therapy, the patient developed blisters with worsening dyspnea and dysphonia. RESULTS: This patient was successfully treated with a combination of oral immunosuppressants and surgical intervention. CONCLUSION: This incident underscores that not all episodes of mucosal ulceration following radiation are a result of mucositis and MMP should be considered in the differential. LEVEL OF EVIDENCE: Level 4.

Management of bilateral conjunctival squamous carcinoma following ocular cicatricial pemphigoid: A case report and review of literature.

The purpose of this study is to report a case of bilateral highly locally invasive conjunctival squamous neoplasia in the clinical setting of ocular cicatricial pemphigoid (OCP), and to review the available literature about this rare association.Case description: A man presented with chronic bilateral conjunctivitis and forniceal foreshortening. He had been previously diagnosed with OCP, and received proper therapy with systemic Dapsone and local steroids. After six months from treatment initiation, the patient complained of worsening symptoms and underwent two more biopsies, revealing a bilateral conjunctival squamous neoplasia. Conclusion: In rare cases, OCP can be associated with conjunctival squamous neoplasia. In case of suspected clinical modifications, it is important to make an early diagnosis by repeating several conjunctival biopsies or by performing less invasive diagnostic techniques (e.g. impression cytology of the ocular surface epithelium) to avoid unnecessary surgical damages.

Mucous Membrane Pemphigoid: A Case Report with Oral and Ocular Presentation.

AIM: To describe the diagnosis and management of mucous membrane pemphigoid (MMP) with oral and ocular presentation. BACKGROUND: Mucous membrane pemphigoid constitutes a heterogeneous group of chronic, autoimmune vesiculobullous diseases characterized by blister formation that has a propensity to affect different mucous membranes of the body. The most commonly affected areas include the oral cavity, mucous membranes of the eyes, throat, genitalia, and nose. This disease usually affects elderly women with a peak incidence at around 50-70 years of age; however, rare cases have been diagnosed in children. The symptoms of MMP include recurrent blistering lesions which eventually rupture and occasionally heal with scarring that may lead to certain complications involving the eyes and throat regions. CASE DESCRIPTION: In this report, we describe a 66-year-old female patient who complained of oral and ocular lesions for a period of 2 years. Pain, burning mouth, and gingival inflammation were present. Ocular examination showed mild conjunctivitis with scar formation at the lateral canthus of the left eye. The patient also noticed periods of water-filled balloon-like formation in the gingiva that rupture spontaneously leaving sore spots. A biopsy was obtained from perilesional tissue and sent for histopathological examination, correlation of clinical and histological features directed us toward the diagnosis of MMP. The patient was treated for both oral and ocular lesions using topical corticosteroid therapy in conjunction with antifungal and antibacterial drugs. The response to local treatment was augmented via effective periodontal therapy to control the concurrent plaque-induced gingival inflammation and via using a customized application tray to sustain the drug efficacy. CONCLUSION: A multidisciplinary approach is often necessary in order to treat MMP lesions efficaciously. CLINICAL SIGNIFICANCE: Early diagnosis and effective treatment protocol using systemic or topical corticosteroid therapy along with other therapeutic means including periodontal therapy, good oral hygiene practice, and timely follow-up are very useful in preventing long-term complications due to this disease.