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Azathioprine: its uses in dermatology İ How to cite this article: Chavez-Alvarez S, Herz-Ruelas M, Villareal-Martinez A, Ocampo-Candiani J, Garza-Garza R, Gomez-Flores M. Azathioprine: its uses in dermatology. An Bras Dermatol. 2020. https://doi.org/10.1016/j.abd.2020.05.003 ,☆☆ İİ Study conducted at the University Hospital “Dr. Jose Eleuterio Gonzalez”, Nuevo León, México.

Abstract

This is a narrative review of azathioprine. This medication is immunomodulatory and immunosuppressive, and it has been used widely through different medical specialties to modify disease. It has been proven useful for several dermatoses and it has encountered success when used as an off-label indication for other dermatologic diseases. Its mechanism of action is described thoroughly, as well as precautions for monitoring adequate levels in patients using it. Dermatologists should also be aware of the possible adverse events it may present. In dermatology it can be used in bullous and autoimmune diseases, and in other conditions, including intractable pruritus, atopic dermatitis, photodermatoses, psoriasis, and others. Azathioprine offers an alternative as a steroid-sparing agent and this review helps dermatologists prescribe it safely to all patients who require it.

KEYWORDS
Autoimmunity; Azathioprine; Pemphigus

Introduction

Azathioprine was first used to prevent graft-versus-host disease. Today it is widely used as an immunomodulator, immunosuppressant, and a steroid-sparing agent.

It is a pro-drug that is rapidly converted to 6-mercaptopurine (6-MP) by means of the purine metabolism pathway, and its therapeutic effects are derived from its purine anti-metabolism.11 Schram ME, Borgonjen RJ, Bik CM, van der Schroeff JG, van Everdingen JJ, Spuls PI. Off-label use of azathioprine in dermatology: a systematic review. Arch Dermatol. 2011;147:474-88. As a purine analogue, it inhibits DNA production and exerts effects on cells with a high proliferation rate (i.e., T and B lymphocytes).22 Sidbury R, Davis DM, Cohen DE, Cordoro KM, Berger TG, Bergman JN, et al. Guidelines for the management of atopic dermatitis: section 3. Management and treatment with phototherapy and systemic agents. J Am Acad Dermatol. 2014;71:327-49.

It is an approved to prevent graft vs. host disease in organ transplant recipients, severe rheumatoid arthritis, systemic lupus erythematosus, and atopic dermatitis.22 Sidbury R, Davis DM, Cohen DE, Cordoro KM, Berger TG, Bergman JN, et al. Guidelines for the management of atopic dermatitis: section 3. Management and treatment with phototherapy and systemic agents. J Am Acad Dermatol. 2014;71:327-49.,33 Anstey AV, Wakelin S, Reynolds NJ. Guidelines for prescribing azathioprine in dermatology. Br J Dermatol. 2004;151:1123-32. In dermatology, it is used off-label for other several conditions.22 Sidbury R, Davis DM, Cohen DE, Cordoro KM, Berger TG, Bergman JN, et al. Guidelines for the management of atopic dermatitis: section 3. Management and treatment with phototherapy and systemic agents. J Am Acad Dermatol. 2014;71:327-49.,33 Anstey AV, Wakelin S, Reynolds NJ. Guidelines for prescribing azathioprine in dermatology. Br J Dermatol. 2004;151:1123-32.

Metabolism and pharmacodynamics

It is synthesized from 6-MP and an imidazolic ring in the sulfur atom which stabilizes the molecule and avoids immediate catabolism.44 Patel AA, Swerlick RA, McCall CO. Azathioprine in dermatology: the past, the present, and the future. J Am Acad Dermatol. 2006;55:369-89. This purine antimetabolite inhibits the S phase of the cell cycle. The metabolism of endogenous purines produces 6-MP.55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34. Three metabolic pathways exist within liver and erythrocytes: xanthine oxidase, thiopurine methyltransferase (TPMT), and hypoxanthine phosphoribosyltransferase. The latter is responsible for the drug's activity, while the first two are the main catabolic pathways and produce inactive metabolites like thiouric acid (Fig. 1).55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34.,66 Tavadia SMB, Mydlarski PR, Reis MD, Mittmann N, Pinkerton PH, Shear N, et al. Screening for azathioprine toxicity: a pharmacoeconomic analysis based on a target case. J Am Acad Dermatol. 2000;42:628-32.

Figure 1
Azathioprine metabolism.

For 6-MP to affect the synthesis of nucleic acids, it needs to be converted into thioinosinic acid.77 Hacker SM, Ramos-Caro FA, Ford MJ, Flowers FP. Azathioprine: a forgotten alternative for treatment of severe psoriasis. Int J Dermatol. 1992;31:873-4. This nucleotide inhibits mitosis, coenzyme formation, neutrophils, and monocytes, as well as suppressing the synthesis of prostaglandins by means of cyclooxygenase (COX).77 Hacker SM, Ramos-Caro FA, Ford MJ, Flowers FP. Azathioprine: a forgotten alternative for treatment of severe psoriasis. Int J Dermatol. 1992;31:873-4. It has a selective activity for T over B lymphocytes.88 Kuhn A, Ruland V, Bonsmann G. Cutaneous lupus erythematosus: update of therapeutic options part II. J Am Acad Dermatol. 2011;65:e195-213. Between 70% and 80% of the drug is absorbed within the gastrointestinal tract and it reaches peak serum levels two hours after ingestion.77 Hacker SM, Ramos-Caro FA, Ford MJ, Flowers FP. Azathioprine: a forgotten alternative for treatment of severe psoriasis. Int J Dermatol. 1992;31:873-4.,99 Meyer V, Beissert S. Azathioprine in the treatment of autoimmune blistering diseases. Dermatol Clin. 2011;29:545-54. It does not cross the blood-brain barrier.44 Patel AA, Swerlick RA, McCall CO. Azathioprine in dermatology: the past, the present, and the future. J Am Acad Dermatol. 2006;55:369-89.

Dose

Adults require 1–3 mg/kg/day and 1–4 mg/kg/day is the pediatric dose.22 Sidbury R, Davis DM, Cohen DE, Cordoro KM, Berger TG, Bergman JN, et al. Guidelines for the management of atopic dermatitis: section 3. Management and treatment with phototherapy and systemic agents. J Am Acad Dermatol. 2014;71:327-49.,55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34. Therapeutic effects are seen one to two months after starting the drug. Dose adjustments must be made according to each patients’ response.55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34.,88 Kuhn A, Ruland V, Bonsmann G. Cutaneous lupus erythematosus: update of therapeutic options part II. J Am Acad Dermatol. 2011;65:e195-213. Administration with meals in divided doses is suggested.33 Anstey AV, Wakelin S, Reynolds NJ. Guidelines for prescribing azathioprine in dermatology. Br J Dermatol. 2004;151:1123-32. Maintenance can extend to 93 months.11 Schram ME, Borgonjen RJ, Bik CM, van der Schroeff JG, van Everdingen JJ, Spuls PI. Off-label use of azathioprine in dermatology: a systematic review. Arch Dermatol. 2011;147:474-88.

Precautions before treatment

It is advisable to thoroughly explain information regarding this medication to the patient. Those unable to be closely monitored are not eligible for treatment.33 Anstey AV, Wakelin S, Reynolds NJ. Guidelines for prescribing azathioprine in dermatology. Br J Dermatol. 2004;151:1123-32.

Request:

  • 1. Antigens for hepatitis B and C, enzyme-linked immunosorbent assay (ELISA) for HIV.

  • 2. Human chorionic gonadotropin (if indicated).

  • 3. Complete blood cell count, blood chemistry, and liver function tests, before treatment and twice a month for the first three months. Finalizing this period, a bimonthly follow-up is required.

  • 4. Annual tuberculosis screening.22 Sidbury R, Davis DM, Cohen DE, Cordoro KM, Berger TG, Bergman JN, et al. Guidelines for the management of atopic dermatitis: section 3. Management and treatment with phototherapy and systemic agents. J Am Acad Dermatol. 2014;71:327-49.

Hepatic or renal malfunction mandates lower doses. If suspension of the medication is required, adverse effects will gradually diminish because of persistence of the active metabolite.55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34.

Patients without a history of varicella zoster infection receiving treatment and recent close contact with the virus should be promptly treated with immunoglobulin. Administration of live virus vaccines for the patient and relatives is prohibited due to the existing risk of transmission. Family members should receive inactivated virus vaccines.33 Anstey AV, Wakelin S, Reynolds NJ. Guidelines for prescribing azathioprine in dermatology. Br J Dermatol. 2004;151:1123-32.

Children over 6 months of age and those not responding to safer medications are eligible. Treatment for short periods may induce prolonged remissions. Dose tapering must be done in six months up to one year.44 Patel AA, Swerlick RA, McCall CO. Azathioprine in dermatology: the past, the present, and the future. J Am Acad Dermatol. 2006;55:369-89.

Fertility is not adversely affected; however, there is scarce evidence.44 Patel AA, Swerlick RA, McCall CO. Azathioprine in dermatology: the past, the present, and the future. J Am Acad Dermatol. 2006;55:369-89. It is advisable to avoid pregnancy and use contraception during treatment.33 Anstey AV, Wakelin S, Reynolds NJ. Guidelines for prescribing azathioprine in dermatology. Br J Dermatol. 2004;151:1123-32. Adverse events include a preterm or underweight child.1010 Murase JE, Heller MM, Butler DC. Safety of dermatologic medications in pregnancy and lactation: Part I. Pregnancy. J Am Acad Dermatol. 2014;401.e1-14; quiz 15.,1111 Dejaco C, Mittermaier C, Reinisch W, Gasche C, Waldhoer T, Strohmer H, et al. Azathioprine treatment and male fertility in inflammatory bowel disease. Gastroenterology. 2001;121:1048-53. Azathioprine passes the placental barrier and the fetal liver lacks enzymes required for its conversion into active metabolites.99 Meyer V, Beissert S. Azathioprine in the treatment of autoimmune blistering diseases. Dermatol Clin. 2011;29:545-54.

Hematological toxicity and sporadic anomalies are also described. There is no established pattern of congenital malformations (which may include atrial or ventricular septal defects). The malformation rate varies from 3% to 9% and includes myelomeningocele, microcephaly, preaxial polydactyly, thymic atrophy, and adrenal hypoplasia and/or hypospadias.99 Meyer V, Beissert S. Azathioprine in the treatment of autoimmune blistering diseases. Dermatol Clin. 2011;29:545-54.

It is a category D drug in pregnancy (acceptable benefits but risks to fetuses). Its use should be reserved for life threatening diseases.1212 Gillibrand PN. Systemic lupus erythematosus in pregnancy treated with azathioprine. Proc R Soc Med. 1966;59:834. Patients should receive half the dose in the 32nd week of gestation if their leukocyte count is less than one standard deviation below the mean. This helps prevent leukopenia and/or thrombocytopenia in the baby.1010 Murase JE, Heller MM, Butler DC. Safety of dermatologic medications in pregnancy and lactation: Part I. Pregnancy. J Am Acad Dermatol. 2014;401.e1-14; quiz 15. A study involving pregnant women receiving azathioprine for eight weeks in the first trimester resulted in scarce evidence linking it to congenital malformations, low birth weight, and/or prematurity.1313 Tagatz GE, Simmons RL. Pregnancy after renal transplantation. Ann Intern Med. 1975;82:113-4. In males, no anomalies in seminal fluid three months after initiation of treatment were described in patients with inflammatory bowel disease (IBD).1414 Shu Kurizky P, Dos Santos Neto LL, Barbosa Aires R, Henrique da Mota LM, Martins Gomes C. Opportunistic tropical infections in immunosuppressed patients. Best Pract Res Clin Rheumatol. 2020:101509.

Breastfeeding is not advisable during treatment due to the risk of tumorigenesis and increased infections in infants.1515 Alami Z, Agier MS, Ahid S, Vial T, Dautriche A, Lagarce L, et al. Pregnancy outcome following in utero exposure to azathioprine: a French comparative observational study. Therapie. 2017. However, a three-year follow-up study in children of patients with IBD receiving azathioprine found no significant differences in the rate of infections compared with children of healthy mothers.1616 Rayburn WF. Connective tissue disorders and pregnancy. Recommendations for prescribing. J Reprod Med. 1998;43:341-9. Most of the 6-MP is excreted in milk four hours following ingestion, though the quantity ingested by infants is not considered significant.1717 Angelberger S, Reinisch W, Messerschmidt A, Miehsler W, Novacek G, Vogelsang H, et al. Long-term follow-up of babies exposed to azathioprine in utero and via breastfeeding. J Crogns Colitis. 2011;5:95-100.

TPMT deficiency

TPMT is an inducible enzyme and its levels vary with time.22 Sidbury R, Davis DM, Cohen DE, Cordoro KM, Berger TG, Bergman JN, et al. Guidelines for the management of atopic dermatitis: section 3. Management and treatment with phototherapy and systemic agents. J Am Acad Dermatol. 2014;71:327-49. Initial measurement of this enzyme is required. Otherwise, there is a risk of adverse effects or treatment at subtherapeutic doses.22 Sidbury R, Davis DM, Cohen DE, Cordoro KM, Berger TG, Bergman JN, et al. Guidelines for the management of atopic dermatitis: section 3. Management and treatment with phototherapy and systemic agents. J Am Acad Dermatol. 2014;71:327-49. Myelosuppression (neutropenia and pancytopenia) may be present with regular doses. An unidentified pancytopenia may become lethal.55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34. Ten percent of individuals have low TPMT activity, which generates thiopurine toxicity.55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34. Resultant accumulation of thioguanine nucleotides affect bone marrow.88 Kuhn A, Ruland V, Bonsmann G. Cutaneous lupus erythematosus: update of therapeutic options part II. J Am Acad Dermatol. 2011;65:e195-213. Those with no TPMT activity should not be prescribed azathioprine.55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34. A greater activity of TPMT confers less risk to induce a myelosuppressive response (Table 1).22 Sidbury R, Davis DM, Cohen DE, Cordoro KM, Berger TG, Bergman JN, et al. Guidelines for the management of atopic dermatitis: section 3. Management and treatment with phototherapy and systemic agents. J Am Acad Dermatol. 2014;71:327-49.

Table 1
Thiopurine methyltransferase (TPMT) levels and azathioprine dosage
Table 2
Azathioprine contraindications.

Applications in dermatology

Pemphigus vulgaris

Used as first-line steroid sparing agent. It offers better results as compared to mycophenolate mofetil (MMF).55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34.,1818 Gregoriou S, Efthymiou O, Stefanaki C, Rigopoulos D. Management of pemphigus vulgaris: challenges and solutions. Clin Cosmet Investg Dermatol. 2015;8:521-7. Another drug, cyclophosphamide, has a faster onset of action; however, treatment effectiveness is comparable at six months.1919 Sardana K, Agarwal P, Bansal S, Uppal B, Garg VK. A comparative effectiveness research of azathioprine and cyclophosphamide on the clinical and serological response in pemphigus vulgaris. Indian J Dermatol. 2016;61:418-26. When combined with prednisone, final outcomes are better, with benefits such as a greater number of patients in remission and less adverse effects (Table 2).2020 Cholera M, Chainani-Wu N. Management of pemphigus vulgaris. Adv Ther. 2016;33:910-58.

Bullous pemphigoid

Starting a steroid-sparing agent since the initiation of treatment is advisable. Time of onset of the therapeutic effects for azathioprine varies from one week to seven months. At a four-year follow-up, 44% of patients achieve remission of the disease.11 Schram ME, Borgonjen RJ, Bik CM, van der Schroeff JG, van Everdingen JJ, Spuls PI. Off-label use of azathioprine in dermatology: a systematic review. Arch Dermatol. 2011;147:474-88. It halts disease progression and promotes re-epithelialization as soon as eight weeks of starting treatment.2121 Tirado-Sanchez A, Diaz-Molina V, Ponce-Olivera RM. Efficacy and safety of azathioprine and dapsone as an adjuvant in the treatment of bullous pemphigoid. Allergol Immunopathol (Madr). 2012;40:152-5. MMF is less hepatotoxic, but five times as costly. A faster and complete cure was also demonstrated when compared with MMF (23.8 vs. 42 days).2222 Beissert S, Werfel T, Frieling U, Bohm M, Sticherling M, Stadler R, et al. A comparison of oral methylprednisolone plus azathioprine or mycophenolate mofetil for the treatment of bullous pemphigoid. Arch Dermatol. 2007;143:1536-42. However, no differences in disease control have been identified with prednisolone alone, azathioprine and prednisolone, prednisolone with plasmapheresis, or prednisolone with azathioprine or MMF.2323 Khandpur S, Verma P. Bullous pemphigoid. Indian J Dermatol Venereol Leprol. 2011;77:450-5.

Chronic actinic dermatitis

It induces 57% to 92% of improvement in patients when compared with placebo. Dosage varies between 1–2.5 mg/kg. Adverse effects observed in patients treated with azathioprine for this condition include three deaths, 12–15 months after stopping treatment (secondary to cerebrovascular disease, lung disease, and another due to heart disease).11 Schram ME, Borgonjen RJ, Bik CM, van der Schroeff JG, van Everdingen JJ, Spuls PI. Off-label use of azathioprine in dermatology: a systematic review. Arch Dermatol. 2011;147:474-88. It has demonstrated effectiveness in refractory disease. Drug interactions need to be reviewed since these patients have polypharmacy, which is why it is preferred over cyclosporine.2424 Forsyth EL, Millard TP. Diagnosis and pharmacological treatment of chronic actinic dermatitis in the elderly: an update. Drugs Aging. 2010;27:451-6.

Psoriasis

It may be indicated for patients with refractory disease.11 Schram ME, Borgonjen RJ, Bik CM, van der Schroeff JG, van Everdingen JJ, Spuls PI. Off-label use of azathioprine in dermatology: a systematic review. Arch Dermatol. 2011;147:474-88. It can be used in conjunction with biologicals (not recommended as monotherapy).55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34. Combined with infliximab (5 mg/kg), it induces improvement.2525 Gupta R. Prolonged remission of psoriasis with azathioprine pulse therapy. Indian J Dermatol. 2015;60:360-3. Intermittent pulse monotherapy may be effective giving 500 mg doses administered for three consecutive days each month, and 100 mg daily continuously for 12 to 24 months. Remission may be achieved for more than five years in some patients.2626 Dalaker M, Bonesronning JH. Long-term maintenance treatment of moderate-to-severe plaque psoriasis with infliximab in combination with methotrexate or azathioprine in a retrospective cohort. J Eur Acad Dermatol Venereol. 2009;23:277-82.

Atopic dermatitis

Information is scarce; however, it has been shown to be as effective as methotrexate.11 Schram ME, Borgonjen RJ, Bik CM, van der Schroeff JG, van Everdingen JJ, Spuls PI. Off-label use of azathioprine in dermatology: a systematic review. Arch Dermatol. 2011;147:474-88.,2727 Weidinger S, Novak N. Atopic dermatitis. Lancet. 2016;387:1109-22.,2828 Vestergaard C, Deleuran M. Advances in the diagnosis and therapeutic management of atopic dermatitis. Drugs. 2014;74:757-69. It is recommended for recalcitrant variants in pediatric patients or when there is a significant psychosocial impact on the patient and their family.22 Sidbury R, Davis DM, Cohen DE, Cordoro KM, Berger TG, Bergman JN, et al. Guidelines for the management of atopic dermatitis: section 3. Management and treatment with phototherapy and systemic agents. J Am Acad Dermatol. 2014;71:327-49.

It can be used in combination and as a steroid-sparing agent.11 Schram ME, Borgonjen RJ, Bik CM, van der Schroeff JG, van Everdingen JJ, Spuls PI. Off-label use of azathioprine in dermatology: a systematic review. Arch Dermatol. 2011;147:474-88. It reduces the SAS-SAD scale by 26% when compared with placebo (3%) after three months of treatment.2929 Meggitt SJ, Gray JC, Reynolds NJ. Azathioprine dosed by thiopurine methyltransferase activity for moderate-to-severe atopic eczema: a double-blind, randomized controlled trial. Lancet. 2006;367:839-46. When used for 12 weeks, the activity of the dermatosis was reduced by 37% vs. 20% in the placebo group.3030 Fotis L, Tuttle PV, Baszis KW, Pepmueller PH, Moore TL, White AJ. Azathioprine therapy for steroid-resistant Henoch-Schönlein purpura: a report of 6 cases. Pediatr Rheumatol Online J. 2016;14:37. A 27% improvement in the severity scoring of atopic dermatitis (SSAD) was also demonstrated after six months.11 Schram ME, Borgonjen RJ, Bik CM, van der Schroeff JG, van Everdingen JJ, Spuls PI. Off-label use of azathioprine in dermatology: a systematic review. Arch Dermatol. 2011;147:474-88.

Cutaneous vasculitis

It is effective when combined with prednisolone for purpura, ulcers, nail fold microinfarcts, and/or peripheral necrosis at 2 mg/kg. There is significant improvement in vasculitis after 18 months of treatment, and 88% of patients achieved complete remission. Side effects included septic arthritis, epidural abscess, gastrointestinal effects, and an isolated death from renal failure (due to severe vasculitis).11 Schram ME, Borgonjen RJ, Bik CM, van der Schroeff JG, van Everdingen JJ, Spuls PI. Off-label use of azathioprine in dermatology: a systematic review. Arch Dermatol. 2011;147:474-88.

For leukocytoclastic vasculitis it is recommended as a second-line therapy in steroid resistant Henoch–Schoenlein purpura, but it has been used successfully and has improved the course of nephritis.3131 Jones RB, Furuta S, Tervaert JW, Hauser T, Luqmani R, Morgan MD, et al. Rituximab versus cyclophosphamide in ANCA-associated renal vasculitis: 2-year results of a randomized trial. Ann Rheum Dis. 2015;74:1178-82.

In ANCA vasculitis, azathioprine vs. rituximab were compared to maintain remission of the disease. More patients remained in remission at 28 months with rituximab vs. azathioprine.3232 Maley A, Swerlick RA. Azathioprine treatment of intractable pruritus: a retrospective review. J Am Acad Dermatol. 2015;73:439-43.

Intractable pruritus

In a retrospective study of patients with chronic pruritus (85% of patients with symptoms for 12 months or more) who transiently responded to a course of systemic steroids but were refractory to other treatments, azathioprine was initiated, with a mean starting dose of 137.5 mg/day. The pruritus scale was modified from a 9 to a 1 or 2.3333 Christensen LA, Dahlerup JF, Nielsen MJ, Fallingborg JF, Schmiegelow K. Azathioprine treatment during lactation. Aliment Pharmacol Ther. 2008;28:1209-13.

Connective tissue diseases (lupus)

Useful in refractory subacute cutaneous lupus erythematosus, generalized discoid lupus, and the erosive palmoplantar type, demonstrating a complete or partial improvement. Rowell's syndrome shows good therapeutic response when combined with prednisolone.88 Kuhn A, Ruland V, Bonsmann G. Cutaneous lupus erythematosus: update of therapeutic options part II. J Am Acad Dermatol. 2011;65:e195-213.

For systemic lupus erythematosus with cutaneous manifestations and nephritis, 1 mg/kg daily can be added to cyclophosphamide (0.05 to 1.00 g/m2 body surface per month for six months).3434 Knott HM, Martinez JD. Innovative management of lupus erythematosus. Dermatol Clin. 2010;28:489-99.

Dermatomyositis

In retrospective case series, it has been shown to be effective. It is considered equally effective when compared to methotrexate. If patients have an inadequate response to these medications, combined treatment offers good results in refractory disease.3535 Oddis CV. Update on the pharmacological treatment of adult myositis. J Intern Med. 2016;280:63-74. It is also recommended to prevent relapses for long periods (one to three years).3636 Sunderkotter C, Nast A, Worm M, Dengler R, Dorner T, Ganter H, et al. Guidelines on dermatomyositis – excerpt from the interdisciplinary S2k guidelines on myositis syndromes by the German Society of Neurology. J Stscg Dermatol Ges. 2016;14:321-38.

Other uses in dermatology

In an open-label pilot, uncontrolled study for moderate and severe alopecia areata a 2 mg/kg dose provided remarkable improvement.3737 Farshi S, Mansouri P, Safar F, Khiabanloo SR. Could azathioprine be considered as a therapeutic alternative in the treatment of alopecia areata?. A pilot study. Int J Dermatol. 2010;49:1188-93. In a prospective study with 14 patients diagnosed with the universalis variant, recalcitrant to other systemic and topical therapies, 43% had a therapeutic response with a mean dose of 142 mg daily and a mean duration of therapy of ten months. Total regrowth was seen in 63% and 29% maintained response at 18 months of follow-up.3838 Vano-Galvan S, Hermosa-Gelbard A, Sanchez-Neila N, Miguel-Gomez L, Saceda-Corralo D, Rodrigues-Barata R, et al. Treatment of recalcitrant adult alopecia areata universalis with oral azathioprine. J Am Acad Dermatol. 2016;74:1007-8.

One case with eosinophilic fasciitis and generalized morphea was treated with 200 mg/day for two months with subsequent tapering to 100 mg/day. Remission was maintained 18 months after treatment.3939 Alonso-Castro L, from Las Heras E, Moreno C, Fleta-Asin B, Munoz-Zato E, Carrillo R, et al. Eosinophilic fasciitis/generalized morphea overlap successfully treated with azathioprine. Int J Dermatol. 2014;53:1386-8.

In sarcoidosis, it has demonstrated improvement in some cases; however, compared with methotrexate, azathioprine exhibited a similar response but greater toxicity.4040 Baughman RP, Lower EE. Newer therapies for cutaneous sarcoidosis: the role of thalidomide and other agents. Am J Clin Dermatol. 2004;5:385-94.

Bullous pemphigoid and psoriasis can co-exist, and cases have been successfully managed with azathioprine (50–150 mg/day). It prevents reactivation of psoriasis when interrupting steroids.4141 Primka EJ, Shirt C. Psoriasis and bullous pemphigoid treated with azathioprine. J Am Acad Dermatol. 1998;39:121-3. In conjunction with acitretin it is used for erythrodermic psoriasis and bullous pemphigoid.4242 Roeder C, Driesch PV. Psoriatic erythroderma and bullous pemphigoid treated successfully with acitretin and azathioprine. Eur J Dermatol. 1999;9:537-9.

Adverse effects/toxicity

Short term

Nausea. This is the most frequent dose dependent adverse effect. It arises at the beginning of treatment and improves even without altering the dose. To avoid it, doses are started at their lowest range; <2.5 mg/kg reduces abandonment rate by 20%.55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34. The dose can be split and taken with meals.33 Anstey AV, Wakelin S, Reynolds NJ. Guidelines for prescribing azathioprine in dermatology. Br J Dermatol. 2004;151:1123-32.

Hypersensitivity to azathioprine. This idiosyncratic reaction is immunologically mediated. It presents within a few weeks of starting the medication. Identification is essential since it may be misinterpreted as a sign of infection. Patients may have fever, myalgia, arthralgia, nausea, hepatitis, interstitial nephritis, renal failure, and pneumonitis.4343 Bidinger JJ, Sky K, Battafarano DF, Henning JS. The cutaneous and systemic manifestations of azathioprine hypersensitivity syndrome. J Am Acad Dermatol. 2011;65:184-91. Cutaneous signs include erythema nodosum, Sweet's syndrome, small vessel vasculitis, acute generalized pustulosis, and other non-specific dermatoses. Hypotension and shock may develop in severe cases.4444 Gisondi P, Piaserico S, Conti A, Naldi L. Dermatologists and SARS-CoV-2: the impact of the pandemic on daily practice. J Eur Acad Dermatol Venereol. 2020 [Epub ahead of print, 22.04.20].

It is possibly underdiagnosed, and atopic eczema patients are the most likely to develop it. Cutaneous signs and symptoms resolve five days after interrupting the drug.55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34.,4444 Gisondi P, Piaserico S, Conti A, Naldi L. Dermatologists and SARS-CoV-2: the impact of the pandemic on daily practice. J Eur Acad Dermatol Venereol. 2020 [Epub ahead of print, 22.04.20].

Medium term

Myelotoxicity. This is characterized by leukopenia, thrombocytopenia, anemia, and/or pancytopenia.77 Hacker SM, Ramos-Caro FA, Ford MJ, Flowers FP. Azathioprine: a forgotten alternative for treatment of severe psoriasis. Int J Dermatol. 1992;31:873-4. Neutropenia is dose dependent. This serious side effect may happen more often than presumed. Approximately 19% of patients develop neutropenia.55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34.

Clinical infection, pharyngeal ulceration, ecchymosis, and/or bleeding can lead to its identification. Monitoring is required if there is a decrease in platelet and white blood cell count within the normal lower limit. If lymphocytes decrease <0.50 k/uL, it is advisable to reduce the dose. If alterations in platelet count show <50 k/uL and/or neutrophils are <1.0 k/uL, a hematology consultation is recommended.33 Anstey AV, Wakelin S, Reynolds NJ. Guidelines for prescribing azathioprine in dermatology. Br J Dermatol. 2004;151:1123-32.

Infections. There is increased susceptibility to infections due to lymphopenia even without neutropenia. Latent tuberculosis patients are at risk of reactivation when starting treatment.55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34.

Hepatotoxicity. Reversible portal fibrosis and/or minimal cholestasis may develop.77 Hacker SM, Ramos-Caro FA, Ford MJ, Flowers FP. Azathioprine: a forgotten alternative for treatment of severe psoriasis. Int J Dermatol. 1992;31:873-4. Mild changes in liver function tests without serious clinical implications are frequent. There are two types of hepatotoxicity for azathioprine: idiosyncratic acute liver injury, with hepatocellular disease (severe transaminase increase) or cholestasis (increase in alkaline phosphatase and bilirubin).55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34. These resolve by decreasing or withdrawing medication.33 Anstey AV, Wakelin S, Reynolds NJ. Guidelines for prescribing azathioprine in dermatology. Br J Dermatol. 2004;151:1123-32.,55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34. Serious hepatotoxicity is rare.55 Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34.

Long term

There is a risk of cutaneous infections and hematological or cutaneous neoplasms.77 Hacker SM, Ramos-Caro FA, Ford MJ, Flowers FP. Azathioprine: a forgotten alternative for treatment of severe psoriasis. Int J Dermatol. 1992;31:873-4. However, when used exclusively for dermatological conditions, this is unlikely since the dosage is lower and time of use is shorter.11 Schram ME, Borgonjen RJ, Bik CM, van der Schroeff JG, van Everdingen JJ, Spuls PI. Off-label use of azathioprine in dermatology: a systematic review. Arch Dermatol. 2011;147:474-88.

Conclusion

Azathioprine is a useful medication in patients with complex dermatologic conditions and/or resistant to conventional treatments. It has been approved for diseases like lupus, dermatomyositis, and pemphigus vulgaris. It is essential for the dermatologist to adequately educate the patient who will receive the medication for its adverse effects. Physicians should be aware that these undesired effects improve and resolve when azathioprine is decreased or interrupted. It is always recommended to start at the lowest possible dose in order to improve tolerance and to avoid permanent discontinuation of a drug that can be extremely beneficial for the patient.

  • İ
    How to cite this article: Chavez-Alvarez S, Herz-Ruelas M, Villareal-Martinez A, Ocampo-Candiani J, Garza-Garza R, Gomez-Flores M. Azathioprine: its uses in dermatology. An Bras Dermatol. 2020. https://doi.org/10.1016/j.abd.2020.05.003
  • İİ
    Study conducted at the University Hospital “Dr. Jose Eleuterio Gonzalez”, Nuevo León, México.
  • Financial support
    None declared.

References

  • 1
    Schram ME, Borgonjen RJ, Bik CM, van der Schroeff JG, van Everdingen JJ, Spuls PI. Off-label use of azathioprine in dermatology: a systematic review. Arch Dermatol. 2011;147:474-88.
  • 2
    Sidbury R, Davis DM, Cohen DE, Cordoro KM, Berger TG, Bergman JN, et al. Guidelines for the management of atopic dermatitis: section 3. Management and treatment with phototherapy and systemic agents. J Am Acad Dermatol. 2014;71:327-49.
  • 3
    Anstey AV, Wakelin S, Reynolds NJ. Guidelines for prescribing azathioprine in dermatology. Br J Dermatol. 2004;151:1123-32.
  • 4
    Patel AA, Swerlick RA, McCall CO. Azathioprine in dermatology: the past, the present, and the future. J Am Acad Dermatol. 2006;55:369-89.
  • 5
    Meggitt SJ, Anstey AV, Mohd Mustapa MF, Reynolds NJ, Wakelin S. British Association of Dermatologists’ guidelines for the safe and effective prescribing of azathioprine 2011. Br J Dermatol. 2011;165:711-34.
  • 6
    Tavadia SMB, Mydlarski PR, Reis MD, Mittmann N, Pinkerton PH, Shear N, et al. Screening for azathioprine toxicity: a pharmacoeconomic analysis based on a target case. J Am Acad Dermatol. 2000;42:628-32.
  • 7
    Hacker SM, Ramos-Caro FA, Ford MJ, Flowers FP. Azathioprine: a forgotten alternative for treatment of severe psoriasis. Int J Dermatol. 1992;31:873-4.
  • 8
    Kuhn A, Ruland V, Bonsmann G. Cutaneous lupus erythematosus: update of therapeutic options part II. J Am Acad Dermatol. 2011;65:e195-213.
  • 9
    Meyer V, Beissert S. Azathioprine in the treatment of autoimmune blistering diseases. Dermatol Clin. 2011;29:545-54.
  • 10
    Murase JE, Heller MM, Butler DC. Safety of dermatologic medications in pregnancy and lactation: Part I. Pregnancy. J Am Acad Dermatol. 2014;401.e1-14; quiz 15.
  • 11
    Dejaco C, Mittermaier C, Reinisch W, Gasche C, Waldhoer T, Strohmer H, et al. Azathioprine treatment and male fertility in inflammatory bowel disease. Gastroenterology. 2001;121:1048-53.
  • 12
    Gillibrand PN. Systemic lupus erythematosus in pregnancy treated with azathioprine. Proc R Soc Med. 1966;59:834.
  • 13
    Tagatz GE, Simmons RL. Pregnancy after renal transplantation. Ann Intern Med. 1975;82:113-4.
  • 14
    Shu Kurizky P, Dos Santos Neto LL, Barbosa Aires R, Henrique da Mota LM, Martins Gomes C. Opportunistic tropical infections in immunosuppressed patients. Best Pract Res Clin Rheumatol. 2020:101509.
  • 15
    Alami Z, Agier MS, Ahid S, Vial T, Dautriche A, Lagarce L, et al. Pregnancy outcome following in utero exposure to azathioprine: a French comparative observational study. Therapie. 2017.
  • 16
    Rayburn WF. Connective tissue disorders and pregnancy. Recommendations for prescribing. J Reprod Med. 1998;43:341-9.
  • 17
    Angelberger S, Reinisch W, Messerschmidt A, Miehsler W, Novacek G, Vogelsang H, et al. Long-term follow-up of babies exposed to azathioprine in utero and via breastfeeding. J Crogns Colitis. 2011;5:95-100.
  • 18
    Gregoriou S, Efthymiou O, Stefanaki C, Rigopoulos D. Management of pemphigus vulgaris: challenges and solutions. Clin Cosmet Investg Dermatol. 2015;8:521-7.
  • 19
    Sardana K, Agarwal P, Bansal S, Uppal B, Garg VK. A comparative effectiveness research of azathioprine and cyclophosphamide on the clinical and serological response in pemphigus vulgaris. Indian J Dermatol. 2016;61:418-26.
  • 20
    Cholera M, Chainani-Wu N. Management of pemphigus vulgaris. Adv Ther. 2016;33:910-58.
  • 21
    Tirado-Sanchez A, Diaz-Molina V, Ponce-Olivera RM. Efficacy and safety of azathioprine and dapsone as an adjuvant in the treatment of bullous pemphigoid. Allergol Immunopathol (Madr). 2012;40:152-5.
  • 22
    Beissert S, Werfel T, Frieling U, Bohm M, Sticherling M, Stadler R, et al. A comparison of oral methylprednisolone plus azathioprine or mycophenolate mofetil for the treatment of bullous pemphigoid. Arch Dermatol. 2007;143:1536-42.
  • 23
    Khandpur S, Verma P. Bullous pemphigoid. Indian J Dermatol Venereol Leprol. 2011;77:450-5.
  • 24
    Forsyth EL, Millard TP. Diagnosis and pharmacological treatment of chronic actinic dermatitis in the elderly: an update. Drugs Aging. 2010;27:451-6.
  • 25
    Gupta R. Prolonged remission of psoriasis with azathioprine pulse therapy. Indian J Dermatol. 2015;60:360-3.
  • 26
    Dalaker M, Bonesronning JH. Long-term maintenance treatment of moderate-to-severe plaque psoriasis with infliximab in combination with methotrexate or azathioprine in a retrospective cohort. J Eur Acad Dermatol Venereol. 2009;23:277-82.
  • 27
    Weidinger S, Novak N. Atopic dermatitis. Lancet. 2016;387:1109-22.
  • 28
    Vestergaard C, Deleuran M. Advances in the diagnosis and therapeutic management of atopic dermatitis. Drugs. 2014;74:757-69.
  • 29
    Meggitt SJ, Gray JC, Reynolds NJ. Azathioprine dosed by thiopurine methyltransferase activity for moderate-to-severe atopic eczema: a double-blind, randomized controlled trial. Lancet. 2006;367:839-46.
  • 30
    Fotis L, Tuttle PV, Baszis KW, Pepmueller PH, Moore TL, White AJ. Azathioprine therapy for steroid-resistant Henoch-Schönlein purpura: a report of 6 cases. Pediatr Rheumatol Online J. 2016;14:37.
  • 31
    Jones RB, Furuta S, Tervaert JW, Hauser T, Luqmani R, Morgan MD, et al. Rituximab versus cyclophosphamide in ANCA-associated renal vasculitis: 2-year results of a randomized trial. Ann Rheum Dis. 2015;74:1178-82.
  • 32
    Maley A, Swerlick RA. Azathioprine treatment of intractable pruritus: a retrospective review. J Am Acad Dermatol. 2015;73:439-43.
  • 33
    Christensen LA, Dahlerup JF, Nielsen MJ, Fallingborg JF, Schmiegelow K. Azathioprine treatment during lactation. Aliment Pharmacol Ther. 2008;28:1209-13.
  • 34
    Knott HM, Martinez JD. Innovative management of lupus erythematosus. Dermatol Clin. 2010;28:489-99.
  • 35
    Oddis CV. Update on the pharmacological treatment of adult myositis. J Intern Med. 2016;280:63-74.
  • 36
    Sunderkotter C, Nast A, Worm M, Dengler R, Dorner T, Ganter H, et al. Guidelines on dermatomyositis – excerpt from the interdisciplinary S2k guidelines on myositis syndromes by the German Society of Neurology. J Stscg Dermatol Ges. 2016;14:321-38.
  • 37
    Farshi S, Mansouri P, Safar F, Khiabanloo SR. Could azathioprine be considered as a therapeutic alternative in the treatment of alopecia areata?. A pilot study. Int J Dermatol. 2010;49:1188-93.
  • 38
    Vano-Galvan S, Hermosa-Gelbard A, Sanchez-Neila N, Miguel-Gomez L, Saceda-Corralo D, Rodrigues-Barata R, et al. Treatment of recalcitrant adult alopecia areata universalis with oral azathioprine. J Am Acad Dermatol. 2016;74:1007-8.
  • 39
    Alonso-Castro L, from Las Heras E, Moreno C, Fleta-Asin B, Munoz-Zato E, Carrillo R, et al. Eosinophilic fasciitis/generalized morphea overlap successfully treated with azathioprine. Int J Dermatol. 2014;53:1386-8.
  • 40
    Baughman RP, Lower EE. Newer therapies for cutaneous sarcoidosis: the role of thalidomide and other agents. Am J Clin Dermatol. 2004;5:385-94.
  • 41
    Primka EJ, Shirt C. Psoriasis and bullous pemphigoid treated with azathioprine. J Am Acad Dermatol. 1998;39:121-3.
  • 42
    Roeder C, Driesch PV. Psoriatic erythroderma and bullous pemphigoid treated successfully with acitretin and azathioprine. Eur J Dermatol. 1999;9:537-9.
  • 43
    Bidinger JJ, Sky K, Battafarano DF, Henning JS. The cutaneous and systemic manifestations of azathioprine hypersensitivity syndrome. J Am Acad Dermatol. 2011;65:184-91.
  • 44
    Gisondi P, Piaserico S, Conti A, Naldi L. Dermatologists and SARS-CoV-2: the impact of the pandemic on daily practice. J Eur Acad Dermatol Venereol. 2020 [Epub ahead of print, 22.04.20].

Publication Dates

  • Publication in this collection
    30 Nov 2020
  • Date of issue
    Nov-Dec 2020

History

  • Received
    13 Jan 2020
  • Accepted
    19 May 2020
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