Azathioprine

Ocular side effects of antirheumatic medications: a qualitative review

Topic

This paper reviews the ocular side effects of medications used in the treatment of rheumatological conditions.

Clinical relevance

Rheumatic diseases are inflammatory conditions that may affect the skin, blood vessels, joints, muscles and internal organs. Immunosuppressive agents are often used as treatment and while powerful, they carry side effects and toxicities that need careful monitoring. Ophthalmic complications have been reported with the use of antirheumatic medications; however, there is a lack of literature synthesising these reports. This paper addresses this gap and hopes to inform both rheumatologists and ophthalmologists as they work together on the management of patients with rheumatological conditions.

Methods

PubMed literature search was conducted from November to September 2019 searching for ocular side effects with the use of 25 rheumatological drugs.

Results

A total of 111 papers were included in this review. Adverse side effects were divided into non-infectious and infectious causes. Traditional disease-modifying antirheumatic drugs (DMARDs) were associated with pruritus, irritation and dryness of the conjunctiva while biologic DMARDS showed reports of new-onset/recurrent uveitis and demyelinating conditions. Infectious side effects included episodes of cytomegalovirus retinitis, toxoplasmic chorioretinitis and endophthalmitis. Other serious side effects were encountered and included in this review.

Conclusion

The goal of this paper is to inform healthcare providers about potential ocular side effects from rheumatological medications. Healthcare providers are encouraged to learn more about these ophthalmic complications and find relevance within their clinical practice.

Autoimmune bullous dermatoses in the elderly: an update on pathophysiology, diagnosis and management

Elderly individuals are susceptible to autoimmune bullous dermatoses (ABDs), which may be associated with high morbidity and mortality. ABDs result from an autoimmune response to components of the basement membrane zone at the dermal-epidermal junction or desmosomes. Bullous pemphigoid results from autoimmunity to hemidesmosomal proteins present in the basement membrane of stratified squamous epithelia. Patients present with tense blisters in flexural areas of the skin. Mild disease may be treated with potent topical corticosteroids, while extensive disease usually requires systemic corticosteroids or systemic immunosuppressive agents such as azathioprine. Mucosal pemphigoid affects one or more mucous membranes that are lined by stratified squamous epithelia. The two most commonly involved sites are the eye and the oral cavity. Lesions frequently result in scar formation that may cause blindness. Patients with severe disease or ocular involvement require aggressive therapy with corticosteroids and cyclophosphamide. Epidermolysis bullosa acquisita results from autoimmunity to type VII collagen in the anchoring fibrils of the basement membrane. Lesions may either arise on an inflammatory base or be non-inflammatory and result primarily from trauma. Treatment options include corticosteroids, dapsone, ciclosporin, methotrexate and plasmapheresis/immunoapheresis. Paraneoplastic pemphigus results from autoimmunity to multiple desmosomal antigens. The disorder is associated with neoplasms, especially leukaemia, lymphoma and thymoma. Patients present with stomatitis and polymorphous skin eruption. The disease may respond to successful treatment of the underlying neoplasm or may require immunosuppressive therapy.

Oral mucosal diseases: Mucous membrane pemphigoid

Subepithelial vesiculobullous conditions are chronic autoimmune disorders that arise from reactions directed against components of the hemidesmosomes or basement membrane zones (BMZ) of stratified squamous epithelium to which the term immune-mediated subepithelial blistering diseases (IMSEBD) has been given. Mucous membrane pemphigoid (MMP) is the most common, but variants do exist. Non-immune disorders that involve these epithelial components typically have a genetic basis--the main example being epidermolysis bullosa. All subepithelial vesiculobullous disorders present as blisters and erosions, and diagnosis must be confirmed by biopsy examination with immunostaining, sometimes supplemented by other investigations. No single treatment reliably controls all subepithelial vesiculobullous disorders; the immunological differences within IMSEBD may account for differences in responses to treatment. Currently, as well as improving oral hygiene, immunomodulatory treatment is used to control the oral lesions of MMP, but it is not known if its specific subsets reliably respond to different agents.

Therapy of autoimmune bullous diseases

Autoimmune bullous diseases result from an immune response to molecular components of the desmosome or basement membrane. Bullous diseases are associated with a high degree of morbidity and occasional mortality. Therapy of bullous diseases consists of suppressing the immune system, controlling inflammation and improving healing of erosions. The therapeutic agents used in the treatment of bullous diseases may be associated with high morbidity and occasional mortality. Successful treatment requires understanding of the pathophysiology of the disease process and the pharmacology of the drugs being used.

Number III Mucous membrane pemphigoid

Mucous membrane pemphigoid (MMP) is a sub-epithelial vesiculobullous disorder. It is now quite evident that a number of sub-epithelial vesiculobullous disorders may produce similar clinical pictures, and also that a range of variants of MMP exist, with antibodies directed against various hemidesmosomal components or components of the epithelial basement membrane. The term immune-mediated sub-epithelial blistering diseases (IMSEBD) has therefore been used. Immunological differences may account for the significant differences in their clinical presentation and responses to therapy, but unfortunately data on this are few. The diagnosis and management of IMSEBD on clinical grounds alone is impossible and a full history, general, and oral examination, and biopsy with immunostaining are now invariably required, sometimes supplemented with other investigations. No single treatment regimen reliably controls all these disorders, and it is not known if the specific subsets of MMP will respond to different drugs. Currently, apart from improving oral hygiene, immunomodulatory-especially immunosuppressive-therapy is typically used to control oral lesions. The present paper reviews pemphigoid, describing the present understanding of this fascinating clinical phenotype, summarising the increasing number of subsets with sometimes-different natural histories and immunological features, and outlining current clinical practice.

Management of autoimmune bullous diseases: Pharmacology and therapeutics

Bullous diseases are associated with high morbidity and mortality. They result from autoimmune response to one or more components of the basement membrane or desmosomes. Management consists of treating the immunologic basis of the disease, treating the inflammatory process involved in lesion formation, and providing supportive care both locally and systemically. Therapeutic agents are chosen based on their known pharmacologic properties and evidence of effectiveness derived from observations and studies. Learning objectives At the completion of this learning activity, participants should be able to understand the pharmacology of drugs used in the treatment of bullous diseases, the principles of therapy for various such diseases, and a practical approach to the management of these diseases.

Autoimmune bullous dermatoses in the elderly: diagnosis and management

Elderly individuals are susceptible to autoimmune bullous dermatoses (in particular, pemphigoid, epidermolysis bullosa acquisita and paraneoplastic pemphigus). Bullous dermatoses are associated with high morbidity and mortality. Bullous dermatoses result from autoimmune responses to one or more components of the basement membrane or desmosomes. Pemphigoid results from autoimmunity to hemidesmosomal proteins present in the basement membrane of stratified squamous epithelia. Patients present with tense blisters in flexural areas of the skin. Mild or moderate bullous pemphigoid may be treated with potent topical corticosteroids while extensive disease usually requires systemic corticosteroids or systemic immunosuppressive agents such as azathioprine. Mucosal pemphigoid affects one or more mucous membranes that are lined by stratified squamous epithelia. The two most commonly involved sites are the eye and the oral cavity. Lesions frequently result in scar formation, which may cause blindness. Patients with severe disease or ocular involvement require aggressive therapy with corticosteroids and cyclophosphamide. Epidermolysis bullosa acquisita results from autoimmunity to type VII collagen in the anchoring fibrils of the basement membrane area. Lesions may either arise on an inflammatory base or be non-inflammatory and result primarily from trauma. The inflammatory type of the disease is more responsive to therapy than the non-inflammatory type. Treatment options include corticosteroids, dapsone, cyclosporin, plasmapheresis and immunoglobulin G. Paraneoplastic pemphigus results from autoimmunity to multiple antigens within the desmosomes. The disorder is associated with neoplasms, especially leukaemia and lymphoma. Patients present with severe stomatitis and polymorphous skin eruption. The mucosal and cutaneous involvement may respond to successful treatment of the underlying neoplasm or may require immunosuppressive therapy.

Immune-mediated hemolytic anemia: understanding the nemesis

IMHA is one of the most common causes of anemia in small animals. Although treatment may be rewarding, many patients do not respond adequately to glucocorticoids alone and require additional immunosuppressive therapy. Some patients may succumb to acute severe anemia and die within the first few weeks of treatment; even if they survive, relapses may occur. IMHA is the nemesis; as our understanding of this disease increases and treatment options expand, it is hoped that survival rates will finally improve.

An open clinical trial of sulphamethoxypyridazine in the treatment of mucous membrane pemphigoid

Twenty-five patients with mucous membrane pemphigoid (MMP), whose oral lesions were unresponsive to topical steroid treatment, were treated with 1 g daily of sulphamethoxypyridazine (SMXP), a long-acting sulphonamide antibiotic, in an open prospective clinical trial. Lesion severity was assessed objectively in a semiquantitative fashion before treatment and after 14 weeks of treatment. The patient's subjective assessment of the associated pain or discomfort, using a visual analogue scale, was also recorded at these times. Three patients (12%) were withdrawn from the study owing to side-effects or complications, one due to an allergic reaction, the other two because of significant haemolysis. For the remainder there was a significant improvement in the mean objective clinical scores for desquamative gingivitis, other oral lesions, conjunctival inflammation, nasal, vulvovaginal and skin involvement, after 14 weeks treatment with SMXP (all P < 0.001, except skin P < 0. 01). Only conjunctival scarring showed no improvement. In addition, there was a significant improvement (P < 0.001) in the pain scores for the mouth, eyes, nose, vulvovaginal region and skin. The results indicate that with appropriate monitoring SMXP is an effective treatment for MMP and compares favourably with other systemic agents used in the management of this condition.

Update on mucous membrane pemphigoid: a heterogeneous immune-mediated subepithelial blistering entity

Most oral involvement in the skin diseases (dermatoses) is related to mucous membrane pemphigoid or lichen planus. Mucous membrane pemphigoid was the subject of a European Symposium held in Turin, Italy, in June 1997. This review is based on that symposium. Mucous membrane pemphigoid is a subepithelial vesiculobullous disorder mainly of late middle age; it has a slight predilection for women. Whereas mucous membrane pemphigoid was formerly considered a single entity, it is now quite evident that a number of subepithelial vesiculobullous disorders may produce similar clinical pictures and also that a range of variants of mucous membrane pemphigoid exists, with antibodies directed against various hemidesmosomal components or components of the epithelial basement membrane. The term immune-mediated subepithelial blistering diseases has therefore been used. Diagnosis and management of immune-mediated subepithelial blistering diseases on clinical grounds alone are impossible; a full history, general and oral examinations, and biopsy with immunostaining are now invariably required, sometimes supplemented with other investigations. Most patients with mucous membrane pemphigoid affecting the mouth manifest desquamative gingivitis, a fairly common complaint typically seen in women who are middle-aged or older. Oral vesicles and erosions may also occur, and there can be a positive Nikolsky sign. Some patients have lesions of other stratified squamous epithelia, presenting as conjunctival, nasal, oesophageal, laryngeal, vulval, penile, or anal involvement. Apart from improving oral hygiene, immunomodulatory-in particular, immunosuppressive-therapy is typically required to control oral lesions in mucous membrane pemphigoid. No single treatment regimen reliably controls all these disorders.

Cicatricial pemphigoid

Cicatricial pemphigoid is a subepidermal blistering disease that involves the mucous membranes and the skin. The oral cavity and the eye are most frequently involved. The clinical course is of long duration, and often there is significant scarring that can have devastating sequelae. The majority of the patients are elderly. The disease is characterized by the in vivo deposition of an anti-basement membrane zone antibody. The anti-basement membrane zone antibody cannot be detected in the circulation by routine laboratory techniques. The pathogenesis is poorly understood, and the cause is not known. Cicatricial pemphigoid may remain localized to the oral cavity or the eye or the skin (Brunsting-Perry variety), or it may be generalized. It rarely occurs in children, and it may be drug induced. Efforts must be made to differentiate cicatricial pemphigoid from bullous pemphigoid, epidermolysis bullosa acquisita, linear IgA bullous disease, and other vesiculobullous disease. Early recognition and treatment can improve the prognosis and avoid surgical intervention. Topical therapy is beneficial and expedites healing. Intralesional corticosteroids are effective and can help reduce the dose of systemic steroids. Most patients require systemic corticosteroid therapy. Dapsone is also useful in treating cicatricial pemphigoid, especially in patients in whom systemic steroids are ineffective or in whom they have to be discontinued because of side effects. Immunosuppressive agents (azathioprine or cyclosphosphamide) are indicated in patients with progressive disease. Occasionally both drugs may be needed.

Bullous and cicatricial pemphigoid

Bullous pemphigoid (BP) and cicatricial pemphigoid are blistering mucocutaneous diseases characterized by detachment of the overlying epithelium from its stroma. IgG and complement components are deposited in all affected tissue at the level of blister formation--through the lamina lucida of the epithelium. The primary antibody response is of the IgG 4 subclass, and the antigens recognized by these autoantibodies have been shown to be 230 kD and 180 kD transmembrane proteins unique to the hemidesmosome of stratified squamous epithelial cells. Although it is suspected that these antigens are important in cell-substrate adhesion, this has not been proven. Stanley et al. have recently defined the sequence of a portion of the C terminal end of the 230 kD antigen and Diaz et al. have isolated a cDNA encoding for the 180 kD antigen. Structural data regarding these antigens should prove critical to definition of their presumed function. Therefore, BP is felt to be an autoimmune disease where the cutaneous lesions may solely be a consequence of binding of these antihemidesmosome autoantibodies to the specific antigen, but definitive proof of this assumption is incomplete.

Immunosuppressive therapy for pemphigus vulgaris complicated by malakoplakia of the bladder

Pemphigus vulgaris is an uncommon auto-immune disease which responds well to treatment with corticosteroids and azathioprine. Malakoplakia is a rare granulomatous disease associated with coliform infections and an altered cellular immune response. We report a 68-year-old female patient with pemphigus vulgaris who, after 2 years on maintenance prednisone and azathioprine immunotherapy, developed malakoplakia of the bladder associated with chronic E. coli urinary-tract infection. The malakoplakia responded well to treatment with cotrimoxazole, bethanechol chloride and ascorbic acid, combined with tapering of the corticosteroid dosage. Our patient presents an uncommon but interesting complication of long-term immunosuppressive therapy for pemphigus vulgaris.

Actinic reticuloid in a black man: successful therapy with azathioprine

A 61-year-old black man suffering from actinic reticuloid with contact allergy to four substances, extreme sensitivity to both ultraviolet A and ultraviolet B, normal visible light sensitivity, and negative results on photopatch tests was placed on a regimen of azathioprine, 50 mg twice a day. At 3 months, clinical appearance was unchanged, as was his strong contact allergy; however, tolerance to natural sunlight was markedly improved. At 6 months the clinical appearance and ultraviolet responses were normal; however, strong contact allergy persisted. To our knowledge, this is the first report of actinic reticuloid in a black person. Azathioprine, after giving an excellent clinical response without leukopenia, was discontinued. A further 9-month follow-up showed continued remission. The persistence of contact allergy, despite profound improvement in photosensitivity and the skin's appearance, suggests that the role of contact allergy in the cause of actinic reticuloid is unclear, and the existence and identity of the hypothesized photosensitizer(s) in actinic reticuloid remain unproved.

Pemphigus vulgaris: results of treatment with gold as a steroid-sparing agent in a series of thirteen patients

Between 1974 and 1981, thirteen patients with pemphigus vulgaris were treated with prednisone supplemented by gold salts. Therapy resulted in excellent responses in eleven of the thirteen, with complete remission in seven. At a mean follow-up of 48.8 months, five patients still had complete remission and required no further treatment. Treatment of pemphigus vulgaris initially with prednisone followed by gold compounds is recommended as an important modality with relatively low morbidity and may permit lower effective doses of corticosteroids to be employed, occasionally even permitting their complete withdrawal.