Successful treatment with tofacitinib for anti-melanoma differentiation-associated gene 5 antibody-positive juvenile dermatomyositis: case reports and review of the literature

Although the clinical efficacy of tofacitinib has been reported in adult patients with anti-melanoma differentiation-associated gene 5 (MDA5) antibody-positive (Ab+) dermatomyositis, data on its use in refractory juvenile dermatomyositis (JDM) are scarce. We describe two female Japanese patients with anti-MDA5 Ab + JDM and rapidly progressive interstitial lung disease who achieved remission by adding tofacitinib to existing immunosuppressive drugs and present a literature review. While both patients received various immunosuppressive or anti-inflammatory treatments for induction therapy, remission could not be achieved. Subsequently, tofacitinib was administered to reduce the Krebs von den Lungen-6 level 5 months after diagnosis in one patient; the other patient received tofacitinib 4 months after diagnosis to reduce ferritin levels and skin manifestations. Subsequently, both patients achieved remission, and prednisolone was withdrawn. Tofacitinib reduced the interferon signature associated with dermatomyositis/JDM disease progression and exerted a therapeutic effect on dermatomyositis/JDM. We found six published cases from five articles of tofacitinib for refractory anti-MDA5 Ab + JDM. Except for one case of herpes simplex meningitis, the other cases, including ours, had improved disease activity without severe adverse events, and steroids and immunosuppressive medicines could be tapered. Tofacitinib could be considered an available therapy for refractory anti-MDA5 Ab + JDM.

Clinical Usefulness of T-Cell Receptor Vβ Repertoire Analysis for Differentiating Multisystem Inflammatory Syndrome in Japanese Children From Toxic Shock Syndrome and Kawasaki Disease

The specific expansion of T-cell receptor β chain variable region (TCR-Vβ21.3 + ) CD4 + and CD8 + T cells was observed in Japanese patients with multisystem inflammatory syndrome in children. In contrast, these findings were not observed in patients with toxic shock syndrome and Kawasaki disease. T-cell receptor β chain variable region repertoire analysis to detect specific expansion of Vβ21.3 + T cells might be useful for differentiating multisystem inflammatory syndrome in children from toxic shock syndrome and Kawasaki disease.

Clinical Characteristics of Cryopyrin-Associated Periodic Syndrome and Long-Term Real-World Efficacy and Tolerability of Canakinumab in Japan: Results of a Nationwide Survey

OBJECTIVE

We assess the clinical characteristics of patients with cryopyrin-associated periodic syndrome (CAPS) in Japan and evaluate the real-world efficacy and safety of interleukin-1 (IL-1) inhibitors, primarily canakinumab.

METHODS

Clinical information was collected retrospectively, and serum concentrations of canakinumab and cytokines were analyzed.

RESULTS

A total of 101 patients were included, with 86 and 15 carrying heterozygous germline and somatic mosaic mutations, respectively. We identified 39 mutation types, and the common CAPS-associated symptoms corresponded with those in previous reports. Six patients (5.9% of all patients) died, with four of the deaths caused by CAPS-associated symptoms. Notably, 73.7% of patients (100%, 79.6%, and 44.4% of familial cold autoinflammatory syndrome, Muckle-Wells syndrome, and chronic infantile neurological cutaneous articular syndrome/neonatal onset multisystem inflammatory disease, respectively) achieved complete remission with canakinumab, and early therapeutic intervention was associated with better auditory outcomes. In some patients, canakinumab treatment stabilized the progression of epiphysial overgrowth and improved height gain, visual acuity, and renal function. However, 23.7% of patients did not achieve inflammatory remission with crucial deterioration of organ damage, with two dying while receiving high-dose canakinumab treatment. Serological analysis of canakinumab and cytokine concentrations revealed that the poor response was not related to canakinumab shortage. Four inflammatory nonremitters developed inflammatory bowel disease (IBD)-unclassified during canakinumab treatment. Dual biologic therapy with canakinumab and anti-tumor necrosis factor-α agents was effective for IBD- and CAPS-associated symptoms not resolved by canakinumab monotherapy.

CONCLUSION

This study provides one of the largest epidemiologic data sets for CAPS. Although early initiation of anti-IL-1 treatment with canakinumab is beneficial for improving disease prognosis, some patients do not achieve remission despite a high serum concentration of canakinumab. Moreover, IBD may develop in CAPS after canakinumab treatment.

Anti-Ku antibody-positive systemic sclerosis and idiopathic inflammatory myopathies overlap syndrome in children: a report of two cases and a review of the literature

The occurrence of anti-Ku antibody-positive idiopathic inflammatory myopathy (IIM) in pediatric patients is rare, and therefore, the clinical phenotypes of this disease in such patients remain obscure. We herein report two cases of Japanese female pediatric patients with anti-Ku antibody-positive IIM. One case was unique in that it was complicated by pericardial effusion. Another patient had severe and refractory myositis with immune-mediated necrotizing myopathy. In addition, we reviewed literatures involving a total of 11 pediatric patients with anti-Ku antibody-positive IIM. The median age of the patients was 11 years, and most of them were girls. Skin rash, including erythematous nodules, malar rash, multiple brownish plaques, butterfly rash, heliotrope rash, periorbital edema, and Gottron's papules, was observed in 54.5% of the patients, scleroderma in 81.8%, and skin ulcer in 18.2%. Their serum creatine kinase level ranged from 504 to 10,840 IU/L. Furthermore, joint involvement was observed in 91% of the patients, interstitial lung disease in 18.2%, and esophageal involvement in 9.1%. All patients were treated with corticosteroids in combination with immunosuppressants. Pediatric patients with anti-Ku antibody-positive IIM had unique characteristics compared to adult patients. Skin manifestations, joint involvement and elevation of serum CK levels were more common in children than in adults. In contrast, ILD and esophageal involvement were less common in children than in adults. Although pediatric cases of anti-Ku antibody-positive IIM are rare, patients with IIM need to be tested for the presence of anti-Ku antibodies.

Clinical significance of serum cytokine profiles for differentiating between Kawasaki disease and its mimickers

OBJECTIVES

To investigate the clinical significance of serum cytokine profiles for differentiating between Kawasaki disease (KD) and its mimickers.

METHODS

Patients with KD, including complete KD, KD shock syndrome (KDSS), and KD with macrophage activation syndrome (KD-MAS), and its mimickers, including multisystem inflammatory syndrome in children, toxic shock syndrome, and Yersinia pseudotuberculosis infection, were enrolled. Serum levels of interleukin (IL)-6, soluble tumor necrosis factor receptor type II (sTNF-RII), IL-10, IL-18, and chemokine (C-X-C motif) ligand 9 (CXCL9) were measured using enzyme-linked immunosorbent assay and compared them with clinical manifestations.

RESULTS

Serum IL-6, sTNF-RII, and IL-10 levels were significantly elevated in patients with KDSS. Serum IL-18 levels were substantially elevated in patients with KD-MAS. Patients with KD-MAS and KD mimickers had significantly elevated serum CXCL9 levels compared with those with complete KD. Area under the receiver operating characteristic curve analysis showed that serum IL-6 was the most useful for differentiating KDSS from the others, IL-18 and CXCL9 for KD-MAS from complete KD, and CXCL9 for KD mimickers from complete KD and KD-MAS.

CONCLUSION

Serum cytokine profiles may be useful for differentiating between KD and its mimickers.

The dynamics of laboratory markers reflecting cytokine overproduction in macrophage activation syndrome complicated with systemic juvenile idiopathic arthritis

OBJECTIVES

To validate the correlation between laboratory markers reflecting disease activity of macrophage activation syndrome (MAS) and serum cytokine levels and identify the valuable laboratory markers that change over time for a prompt MAS diagnosis.

METHODS

Serum cytokine levels were determined by enzyme-linked immunosorbent assay and compared with laboratory markers reflecting MAS disease activity.The changes in values were evaluated from the acute phase of systemic juvenile idiopathic arthritis (s-JIA) to MAS diagnosis.

RESULTS

CXCL9 was significantly correlated with aspartate aminotransferase (AST), lactate dehydrogenase (LDH), D dimer, and urine β2 microglobulin levels. sTNF-RII was significantly correlated with platelet counts, AST, LDH, D dimer, and ferritin levels. Significant changes in platelet count, LDH, and D dimer levels were observed. Decreased platelet counts were the most valuable indicator for MAS diagnosis.

CONCLUSION

Monitoring the laboratory markers that change over time, particularly decreased platelet counts, was valuable for the prompt MAS diagnosis in s-JIA.

An infant with A20 haploinsufficiency presenting with periodic fever syndrome: A case report

A20 haploinsufficiency (HA20) is an early-onset autoinflammatory disease caused by loss-of-function variants of the TNFAIP3 gene, which encodes the protein A20. HA20 is typically characterized by Behçet's disease-like clinical symptoms, and patients usually present with a family history. Herein, we report a case of HA20 in a pediatric patient, presenting with periodic fever, abdominal pain, and vomiting, with no family history. This patient also harbored a novel heterozygous frameshift variant c.677del (p.Pro226LeufsTer2) of TNFAIP3. We initiated treatment with an anti-tumor necrosis factor-α agent that did not induce symptom resolution; we thus administered combination therapy, including prednisolone. Remission was then successfully achieved. We suggest that HA20 should be considered when an autoinflammatory disease is suspected and periodic fever syndrome is present, even in the absence of a family history of HA20 or Behçet's disease-like symptoms.

Atrophic autoimmune thyroiditis complicated with systemic lupus erythematosus

Atrophic autoimmune thyroiditis (AAT) is a type of autoimmune thyroiditis that causes hypothyroidism without thyroid enlargement. AAT is distinguished from Hashimoto's disease (HD) by the absence of thyroid enlargement. AAT is rare in children and clinically characterised by severe primary hypothyroidism. Autoimmune thyroiditis, especially HD, is commonly complicated with systemic lupus erythematosus (SLE). Here, we reported the patient with AAT as the initial presentation of SLE complicated with generalised myxoedema, whose presentation was a diagnostic challenge. This patient illustrates the importance of the early recognition of an atypical presentation of SLE patients with autoimmune thyroiditis. It is possible that similar cases have existed in the past but have been overlooked as HD. A large-scale study is necessary to clarify the reality of AAT in SLE.

Reliability of antinuclear matrix protein 2 antibody assays in idiopathic inflammatory myopathies is dependent on target protein properties

A line blotting assay (LB) is currently used to detect myositis-specific autoantibodies (MSAs) in patients with idiopathic inflammatory myopathies (IIMs), because of its simplicity; however, the sensitivity and specificity of this assay is low. The aim of this study is to evaluate the accuracy of the commercial LB in detection of antinuclear matrix protein 2 (NXP2) antibody. Seventy-seven serum samples from patients with IIMs, in which anti-NXP2 antibodies were detected through immunoprecipitation and western blotting (IP-WB) using K562 cell lysate, were enrolled. All samples were assessed by LB and IP-WB using recombinant human NXP2 whole protein (rNXP2) produced by insect cells, and the positive rates of each assay were compared. Thirty-two samples (41.6%) showed false-negativity by LB, which includes 11 samples with negative results by IP-WB using rNXP2. Relative intensities of IP-WB using cell lysate were significantly higher in the samples with positive results by both LB and IP-WB using rNXP2, compared to samples with positive by IP-WB using rNXP2 but negative by LB. Three of 11 samples with negative results by both LB and IP-WB using rNXP2 revealed high antibody titers. Further, differences in post-transcriptional SUMOylation were observed between recombinant and natural NXP2 proteins. In conclusion, the LB showed low sensitivity for detection of anti-NXP2 antibody, an effect exacerbated at low titers of anti-NXP2 antibodies. Moreover, there appears to be differences in the reactivities of antibodies to recombinant and natural NXP2 proteins with different post-transcriptional modifications.

Tacrolimus as an alternative treatment for patients with juvenile idiopathic arthritis

OBJECTIVE

To evaluate the efficacy and safety of tacrolimus in patients with juvenile idiopathic arthritis (JIA).

METHODS

We retrospectively analysed 27 patients with JIA who received tacrolimus therapy at the Department of Pediatric Rheumatology of the Tokyo Medical and Dental University between April 2019 and August 2020. We collected background and clinical characteristics at the time of add-on tacrolimus therapy initiation (baseline; Month 0) and after 3, 6, and 12 months. The primary outcome was successful medication reduction after 12 months. Patients requiring reduced and additional treatments were assigned as 'did not require additional treatment patients' and 'required additional treatment patients', respectively. The Wilcoxon signed-rank test was used to evaluate the continuous distribution of laboratory data and Juvenile Arthritis Disease Activity Score-27 at 3, 6, and 12 months relative to baseline values. Statistical significance was set as p < .05.

RESULTS

Among the 27 included cases, 17 patients were classified as did not require additional treatment patients, and there was a significant improvement in Juvenile Arthritis Disease Activity Score-27 scores in this group (p < .05). No patients presented tacrolimus-related adverse events throughout the study period.

CONCLUSION

Tacrolimus is an effective and safe therapeutic alternative for approximately 60% of patients with JIA.

Anti-nuclear matrix protein 2 antibody-positive inflammatory myopathies represent extensive myositis without dermatomyositis-specific rash

OBJECTIVES

Myositis-specific autoantibodies (MSAs) define distinct clinical subsets of idiopathic inflammatory myopathies (IIMs). The anti-nuclear matrix protein 2 (NXP2) antibody, a MSA detected in juvenile/adult IIMs, has been reported to be associated with a high risk of subcutaneous calcinosis, subcutaneous oedema, and internal malignancies. The study aimed to clarify the clinical features of anti-NXP2 antibody-positive IIMs in detail.

METHODS

This multi-centre retrospective observational study on 76 anti-NXP2 antibody-positive patients. The antibody was detected via a serological assay using immunoprecipitation and western blotting. The patients were selected from 162 consecutive Japanese patients with IIMs.

RESULTS

The cohort of anti-NXP2 antibody-positive IIMs included 29 juvenile patients and 47 adult patients. Twenty-seven (35.5%) patients presented with polymyositis phenotype without dermatomyositis-specific skin manifestations (heliotrope rash or Gottron sign/papules); this was more common in the adults than children (48.9% vs. 15.8%, P < 0.01). Nine (11.8%) patients had subcutaneous calcinosis, and 20 (26.3%) patients had subcutaneous oedema. In addition, the proportion of patients with muscle weakness extending to the distal limbs was high (36 patients [47.4%]) in this cohort. Adult patients had a higher prevalence of malignancy than the general population (age-standardised incidence ratio of malignancies: 22.4).

CONCLUSION

Anti-NXP2 antibody-positive IIMs, which include dermatomyositis sine dermatitis, are characterised by atypical skin manifestations and extensive muscular involvement.

Childhood-onset systemic lupus erythematosus with trisomy X and the increased risk for bone complications: a case report

BACKGROUND

Systemic lupus erythematosus is a multi-organ inflammatory autoimmune disease; immune complexes are part of the pathogenesis, but not entirely responsible. Trisomy X is the most common female chromosomal abnormality and the role of an additional X chromosome in the development of systemic lupus erythematosus is well recognized. However, the potential complications and optimal management of childhood lupus with trisomy X remain unclear. Herein, we describe a case of childhood-onset systemic lupus erythematosus associated with severe bone complications presumably secondary to trisomy X.

CASE PRESENTATION

A 16-year-old Japanese girl was diagnosed with childhood-onset systemic lupus erythematosus and trisomy X. A chromosomal abnormality (47, XXX) was incidentally identified on bone marrow examination initially done to determine the cause of pancytopenia. She had a persistent headache, fever　for six days, diffuse hair loss, mucosal ulcers, butterfly eruptions, and palmar erythema. Furthermore, thrombocytopenia, anemia, and erythrocyte fragmentation were detected, suggesting secondary thrombotic microangiopathy. She was initially treated with intravenous methylprednisolone pulse therapy and prescribed monthly cyclophosphamide for severe disease activity, prednisolone, mycophenolate mofetil, and hydroxychloroquine as remission maintenance drugs. She developed generalized extremity pain that had been worsening throughout the disease. Extremity magnetic resonance imaging performed 12 months after the treatment onset revealed multifocal avascular necrosis, and dual-energy X-ray absorptiometry revealed further decreased bone mineral density. High plasma levels of factor VIII were detected by additional tests for coagulation functions, and we suspected the possibility that factor VIII might cause avascular necrosis due to thrombosis. Currently, she is being treated with prednisolone and MMF for SLE. However, her extremity pain has not been managed effectively even under the administration of non-steroidal anti-inflammatory drugs and pregabalin.

CONCLUSIONS

An additional X chromosome has been reported to be associated with factor VIII and osteoporosis. Additionally, elevated plasma levels of FVIII is the risk factors for thrombosis, which leads to the risk of avascular necrosis. Patients with systemic lupus erythematosus complicated by trisomy X might be at a higher risk of avascular necrosis and osteoporosis that can also manifest in childhood systemic lupus erythematosus.

Importance of pediatric rheumatologists and transitional care for juvenile idiopathic arthritis-associated uveitis: a retrospective series of 9 cases

BACKGROUND

Juvenile idiopathic arthritis-associated uveitis (JIA-U) is a serious condition associated with the risk of blindness. However, pediatric rheumatologists rarely encounter cases of blindness, because most patients reach adulthood during the course of follow-up before blindness occurs. Here, we report the progress of 9 patients with JIA-U, including 2 patients who became blind after the transition period. We aimed to highlight the importance of the role of pediatric rheumatologists and transitional care in preventing blindness associated with JIA-U.

CASE PRESENTATION

We conducted a retrospective analysis of the case records of 9 JIA-U patients (1 male, 8 female; median age 16.8 years, range 5.5-19.8 years). All patients presented with oligo-juvenile idiopathic arthritis (oligo-JIA) (one presented with extended oligo-JIA); the median age of uveitis onset was 5.0 years (range 3.0-13.0 years), and the onset of uveitis preceded the onset of arthritis in 2 patients. The median disease duration was 12.5 years (range 3.5-24.7 years); 4 patients had anti-nuclear antibody (ANA) positivity (≧1:160) (all with a homogeneous and speckled-pattern subtype). All patients were negative for rheumatoid factor. Eight patients received methotrexate, 7 patients received one or more biologic drugs (etanercept, infliximab, adalimumab, and golimumab), and 6 patients required ophthalmic surgery at an early age (≦ 18 years). Two patients developed blindness after the transition period. Medical examination by pediatric rheumatologists and use of biologics had been delayed in both patients. One patient developed depression after transition and interrupted her own treatment.

CONCLUSIONS

The reason for blindness in the 2 patients was thought to be the delay in the commencement of treatment and failure to provide transitional care. Inflammation is difficult to control in JIA-U even with appropriate treatment. Pediatric rheumatologists must be informed about the risk of JIA-U blindness, especially after transition. To ensure a good prognosis, the specialized treatment with the involvement of pediatric rheumatologists is necessary early on, and consideration for transitional medicine is essential. Therefore, this report reaffirms the importance of planned transitional care that has been advocated for globally.

Induced negative pressure proposed as a new method for diagnosing hepatic hydrothorax involving minor leaks

Key Clinical Message

Hepatic hydrothorax is known as pleural effusion of hepatic origin, and is difficult to diagnose. We herein report the novel strategy combining radioisotope scintigraphy with chest drainage to definitively diagnose hepatic hydrothorax of an 85-year-old patient which would have been missed with conventional diagnostic methods.