Thrombocytopenia in systemic lupus erythematosus responsive to dapsone

A retrospective analysis of 122 immune thrombocytopenia patients treated with dapsone: Efficacy, safety and factors associated with treatment response

BACKGROUND

The optimum second-line treatment or best sequence of treatments for immune thrombocytopenia (ITP) are yet to be determined. Our institution has accumulated extensive experience regarding the use of dapsone as second-line therapy for ITP.

OBJECTIVES

We aimed to assess the efficacy rate and safety of dapsone treatment in ITP patients.

PATIENTS/METHODS

Here we report our experience in a retrospective study, including 122 patients, with a median treatment duration with dapsone of 6 months and a median follow-up period of 3.4 years.

RESULTS

The overall response rate in this cohort was 66%, including 24% of complete responses. Among responders, in 24% a relapse occurred while on treatment. Therefore, a sustained response was observed in 51% of patients. Interestingly, 81% of the responders maintained the response after the interruption of treatment, for a median time of 26 months. Side effects were reported in 16% of the patients in this cohort and treatment was interrupted due to side effects in 11% of patients. The main cause in these cases was hemolytic anemia and methemoglobinemia. Reductions in hemoglobin levels during the use of dapsone were seen in 94% of the patients. Responders presented significantly greater reductions in their hemoglobin levels than nonresponders did: median hemoglobin drop of 1.9 g/dl vs. 1.2 g/dl (p = .004).

CONCLUSIONS

Our findings suggest that dapsone has adequate efficacy and is well tolerated. Although the mechanism of action is still unclear, our observation that the degree in the drop of hemoglobin is greater in responders suggest a possible role of the blockage of the reticuloendothelial system in the therapeutic effect of the drug.

Dapsone: An Old but Effective Therapy in Pediatric Refractory Immune Thrombocytopenia

There are no definitive guidelines for management of chronic or refractory immune thrombocytopenia (ITP) in children. Dapsone is an inexpensive and efficacious, yet neglected, therapeutic option for treatment of chronic ITP. We evaluated the efficacy and safety of dapsone in the management of chronic ITP in children. Children with chronic ITP < 14 years with minimum grade 2 bleeds refractory to either splenectomy/rituximab/eltrombopag; who were offered dapsone therapy were retrospectively analyzed. Dapsone intolerance and G6PD deficiency were excluded. Dapsone was started at a dose of 1-2 mg/kg/day. Response to dapsone as per international working group definitions, time to response along with side-effects were noted. Forty-four children enrolled; 29 analyzed. Nineteen were refractory to rituximab, 8 to splenectomy and 6 to eltrombopag. Median age was 9.8 years (3-14) with 16/29 males. Median dapsone dose was 1.59 mg/kg/day (range 1-2.1). Overall response was seen in 21/29 (72%): Complete Response in 7/29 (24%), Partial Response in 14/29 (48%). All responses were sustained for minimum 3 months. Median duration to response was 2.9 months (2-6.6). Median follow up was 28 months (6-73) and relapse rate-21%. Major side effects noted: Methemoglobinemia-01, skin ulceration-02. In three cases dapsone could be tapered and stopped without relapse. Dapsone is an economical and efficacious agent with good safety profile in childhood chronic/refractory ITP.

Efficacy and safety of dapsone as second line therapy for adult immune thrombocytopenia: A retrospective study of 42 patients

Dapsone is recommended as a second line therapy in immune thrombocytopenia (ITP), but is underused because of its potential side effects. The medical charts of 42 ITP patients treated with dapsone (100 mg/day) were retrospectively reviewed in order to assess its efficacy and safety in daily clinical practice. The overall response rate was 54.8% (n = 22, with a complete response in 38.1%) with a median time to response of 29 days (24-41 days). Patients with complete response had shorter disease duration whereas no difference was observed between responders and non-responders regarding age, sex or previous treatments received. Importantly, after dapsone withdrawal, a sustained response was observed in 5 patients, representing 12% of the whole cohort. Twenty percent of patients (n = 8) relapsed on therapy after 8.1 (6.5-13.6) months. Side effects occurred in 31% (n = 13) of patients, and required dapsone withdrawal in 22% (n = 9) or dosage reduction in 10% (n = 4) of the cases. Side effects resolved in all but one case. Overall, these data support dapsone as an interesting second line therapy in ITP, with a good safety and efficacy profile at a low cost.

Dapsone therapy for refractory immune thrombocytopenia patients: a case series

Background

Dapsone has been recommended as a second-line immunosuppressive agent for patients with immune thrombocytopenia (ITP).

Methods

We retrospectively analyzed the efficacy and safety of dapsone therapy in patients with ITP.

Results

Nine ITP patients were treated with dapsone at a dose of 50–100 mg/day between May 2013 and March 2016. All patients were refractory to multiple previous treatments, with a median of 7 agents (range, 4–8), and 3 patients had undergone a previous splenectomy. The median pre-treatment platelet count was 4×10⁹/L (range, 3–27×10⁹/L). Only 1 patient (11.1%) responded to dapsone therapy. No severe adverse events were observed, except for 1 case of dapsone hypersensitivity syndrome.

Conclusion

Although dapsone is still useful for some patients, it may be ineffective in heavily pretreated patients with profound thrombocytopenia.

How I treat refractory immune thrombocytopenia

This article summarizes our approach to the management of children and adults with primary immune thrombocytopenia (ITP) who do not respond to, cannot tolerate, or are unwilling to undergo splenectomy. We begin with a critical reassessment of the diagnosis and a deliberate attempt to exclude nonautoimmune causes of thrombocytopenia and secondary ITP. For patients in whom the diagnosis is affirmed, we consider observation without treatment. Observation is appropriate for most asymptomatic patients with a platelet count of 20 to 30 × 109/L or higher. We use a tiered approach to treat patients who require therapy to increase the platelet count. Tier 1 options (rituximab, thrombopoietin receptor agonists, low-dose corticosteroids) have a relatively favorable therapeutic index. We exhaust all Tier 1 options before proceeding to Tier 2, which comprises a host of immunosuppressive agents with relatively lower response rates and/or greater toxicity. We often prescribe Tier 2 drugs not alone but in combination with a Tier 1 or a second Tier 2 drug with a different mechanism of action. We reserve Tier 3 strategies, which are of uncertain benefit and/or high toxicity with little supporting evidence, for the rare patient with serious bleeding who does not respond to Tier 1 and Tier 2 therapies.

Treatment of Bullous Systemic Lupus Erythematosus

Bullous systemic lupus erythematosus (BSLE) is an autoantibody-mediated vesiculobullous disease in patients with SLE. Autoimmunity in BSLE is characterized by the presence of circulating anti-type VII collagen antibodies. BSLE patients often present with multiple, tense, clear fluid-filled vesicles and bullae overlying erythematous edematous plaques. Skin biopsy from BSLE patients shows subepidermal bullae with numerous neutrophils and only occasional eosinophils. Furthermore, immunofluorescence examination showed linear deposition of lgG, lgA, C3, and C1q along the basement membrane zone. BSLE patients with corticosteroids treatment constantly do not receive a marked improvement, while dapsone generally dramatically improved the skin condition. Recently, it has been reported that quite a few cases of BSLE were successfully treated with other immune suppressive drugs. Therefore, a comprehensive review of the treatment of BSLE would be beneficial to cure the disease.

Haematological manifestations of lupus

Our purpose was to compile information on the haematological manifestations of systemic lupus erythematosus (SLE), namely leucopenia, lymphopenia, thrombocytopenia, autoimmune haemolytic anaemia (AIHA), thrombotic thrombocytopenic purpura (TTP) and myelofibrosis. During our search of the English-language MEDLINE sources, we did not place a date-of-publication constraint. Hence, we have reviewed previous as well as most recent studies with the subject heading SLE in combination with each manifestation. Neutropenia can lead to morbidity and mortality from increased susceptibility to infection. Severe neutropenia can be successfully treated with granulocyte colony-stimulating factor. While related to disease activity, there is no specific therapy for lymphopenia. Severe lymphopenia may require the use of prophylactic therapy to prevent select opportunistic infections. Isolated idiopathic thrombocytopenic purpura maybe the first manifestation of SLE by months or even years. Some manifestations of lupus occur more frequently in association with low platelet count in these patients, for example, neuropsychiatric manifestation, haemolytic anaemia, the antiphospholipid syndrome and renal disease. Thrombocytopenia can be regarded as an important prognostic indicator of survival in patients with SLE. Medical, surgical and biological treatment modalities are reviewed for this manifestation. First-line therapy remains glucocorticoids. Through our review, we conclude glucocorticoids do produce a response in majority of patients initially, but sustained response to therapy is unlikely. Glucocorticoids are used as first-line therapy in patients with SLE with AIHA, but there is no conclusive evidence to guide second-line therapy. Rituximab is promising in refractory and non-responding AIHA. TTP is not recognised as a criteria for classification of SLE, but there is a considerable overlap between the presenting features of TTP and SLE, and a few patients with SLE have concurrent TTP. Myelofibrosis is an uncommon yet well-documented manifestation of SLE. We have compiled the cases that were reported in MEDLINE sources.

Dapsone for primary immune thrombocytopenia in adults and children: an evidence-based review

Primary immune thrombocytopenia is a potentially life-threatening condition. Approximately two-thirds of adult patients do not have a sustained response to steroids (first-line therapy). For these patients, a number of other treatment options exist, such as rituximab, splenectomy, immunosuppressants, and thrombopoietin receptor agonists, but they are costly and have side effects. Dapsone is an inexpensive drug with a well-established safety profile. Unfortunately, this treatment option has not been explored adequately. This review is aimed at analyzing the currently available evidence for the use of dapsone as second-line or third-line therapy in primary immune thrombocytopenia.

Efficacy and safety of dapsone as a second-line treatment in non-splenectomized adults with immune thrombocytopenic purpura

In adults with immune thrombocytopenic purpura (ITP), steroids are usually proposed as first-line therapy, but long-term complete responses are obtained in no more than 20% of patients. For the remaining patients, splenectomy is considered the treatment of choice, with reported "cure" rates from 60-70%. However, the inherent risks of surgery and sepsis after splenectomy without a guarantee of success justify the search for strategies aimed to avoid splenectomy. Here we retrospectively evaluated the results of dapsone treatment in ITP patients that failed first-line therapy with steroids. These patients received dapsone 100 mg/day for a minimum of 30 days before splenectomy was considered. Efficacy was defined as a sustained rise in platelet counts (>50 x 10(9)/l) clearly attributed to dapsone treatment. Among 52 steroid-dependent or refractory patients, dapsone resulted in sustained increases in platelet counts in 44.2% of patients, after a median follow-up of 21.10 months after treatment initiation. The long-term efficacy of dapsone in this setting is further corroborated by the observation that none of the "responding" patients required splenectomy in the follow-up, compared to 69.0% of the "non-responding" patients. Dapsone-related adverse events were mild and promptly reversed by treatment withdrawal. The results of our retrospective analysis suggest that dapsone is a safe and effective second-line agent for steroid-dependent or refractory ITP patients. Because of its well-known safety profile and low cost compared to other potential second-line treatments for ITP, a trial course of dapsone should be viewed as an attractive option before splenectomy in steroid-dependent of refractory adult ITP patients.

Elderly-Onset Systemic Lupus Erythematosus

Systemic lupus erythematosus is an autoimmune multi-system disease of uncertain aetiology with highly variable clinical manifestations. Women of child-bearing age are most often affected; however, approximately 10-20% of cases occur in older patients. Elderly-onset lupus has been defined in various studies as onset of lupus after age 50-65 years. Menopause and changes in cellular immunity with aging may contribute to development of lupus in older adults. Many studies suggest that the clinical and serological features of elderly-onset lupus differ from those of lupus in younger patients. Arthritis, fever, serositis, sicca symptoms, Raynaud's syndrome, lung disease and neuropsychiatric symptoms are more common in patients with elderly-onset lupus, while malar rash, discoid lupus and glomerulonephritis are less common in elderly-onset patients compared with younger lupus patients. Most elderly-onset lupus patients have a positive anti-nuclear antibody test, but the prevalence of anti-double-stranded DNA and hypocomplementaemia is lower in elderly-onset patients than in younger patients. Rheumatoid factor, anti-Ro/Sjögren's syndrome (SS) A and anti-La/SSB are more often positive in elderly-onset patients. The diagnosis of elderly-onset lupus may be delayed for many months: insidious onset, low prevalence and similarity to other more common disorders make the diagnosis of lupus challenging in this population. Treatment of lupus in the elderly may be complicated by co-morbidities and increased risk of toxicities from usual treatments. Optimal management of elderly-onset lupus is empiric because of a lack of randomised controlled studies. However, the approach to treatment is similar regardless of the age of the patient. This article discusses the prevalence, clinical course, serological features, prognosis and treatment of elderly-onset systemic lupus erythematosus.

Dapsone therapy for children with immune thrombocytopenic purpura

Dapsone has been shown to be effective in treating adults with immune thrombocytopenic purpura (ITP). This retrospective review describes the authors' experience using dapsone in children with refractory, symptomatic ITP. Seven children were treated with dapsone. Dapsone was discontinued in two patients because of methemoglobinemia. In the remaining five patients, three achieved platelet counts of more than 100 x 10(3)/microL. Discontinuation resulted in a rapid decline in platelet counts in all three patients. Two of the three responded to a second round of treatment. Additional study of dapsone in children is warranted. Children receiving dapsone should be monitored for methemoglobinemia.

Effects of a novel pyridylsulphonyl thiazole derivative, FR115092, on autoimmune and mitomycin C-induced thrombocytopenia in mice

Dapsone (4,4'-diaminodiphenyl sulphone), an antileprotic and antimalarial drug, has been reported to be of therapeutic benefit in idiopathic thrombocytopenic purpura in the clinic. However, adverse reactions such as haemolytic anaemia have often been observed. In this study, we found that dapsone increased the number of platelets and decreased the number of red blood cells in male (NZWxBXSB)F1 (W/BF1) mice, an animal model of idiopathic thrombocytopenic purpura. In studies to prepare derivatives of dapsone with weaker side effects than the parent compound, FR115092 (2-[5-(2-pyridylsulphonyl)thiazolyl]amine) was discovered. The effect of FR115092 on the number of blood cells was studied and compared with dapsone in mice. FR 115092 increased the number of platelets without reducing the number of red blood cells in W/BF1 mice. This drug significantly suppressed the increase in circulating autoantibodies against platelets and increased the number of megakaryocytes. Furthermore, FR115092 inhibited the reduction of the number of platelets in mitomycin C-induced thrombocytopenic mice, as a consequence of its enhancement of growth and maturation of megakaryocytes. These findings suggest that FR115092 may be effective against various thrombocytopenias, without inducing haemolytic anaemia.

Synthesis and effects of novel thiazole derivatives against thrombocytopenia

5-(2-Pyridylsulfonyl)-2-thiazolamine (2) was effective both in mitomycin C (MMC)-induced thrombocytopenia and in an animal model of idiopathic thrombocytopenic purpura (ITP). It also suppressed the increase of autoantibodies against platelets in the ITP model and showed no blood toxicity. Chemical modification of 2 led to the discovery of more potent compounds against MMC-induced thrombocytopenia.

Dapsone for autoimmune thrombocytopenic purpura

Twenty-one human immunodeficiency virus (HIV)-free and six HIV-infected adults with autoimmune thrombocytopenic purpura (AITP) were treated with dapsone (100 mg/day). A response was observed in 13 patients (median platelet count before 25 x 10(9)/L, range 3-49; after 109 x 10(9)/L, range 69-241). Thrombocytopenia recurred in four of the responders in whom dapsone was discontinued. No response was observed in 12 patients. Dapsone had to be withdrawn after two weeks of treatment in the remaining two patients and after six to eight weeks in three other patients due to intolerance. No serious hematological complications were observed. These results confirm that dapsone is a safe, inexpensive, and effective treatment of AITP.