Sukesh Sukumaran

High Dose Infliximab in the Treatment of Refractory Uveitis: Does Dose Matter?

Background. Infliximab (INF) has been shown to be beneficial in treating refractory uveitis, however, no data exist on optimal dosing and the efficacy of higher dosing. Objectives. To compare the efficacy of low-dose (LD) (<10 mg/kg), moderate-dose (MD) (≥10–15 mg/kg), and high-dose (HD) INF (≥15–20 mg/kg) in the treatment of uveitis. Methods. Retrospective chart review children with uveitis diagnosed at Childrens Hospital Los Angeles and Millers Childrens Hospital, CA, USA. Results. Of the 34 INF-treated children, 6 patients received LD, 19 received MD, and 9 received HD. Average disease duration prior to therapy was 10.6, 24.6, and 37.1 months each group, respectively. Topical steroids were discontinued after an average of 3 months, 9.5 months, and 10.2 months in the LD, MD, and HD groups, respectively. We found that 66% of patients receiving LD, 42% of MD, and 66% receiving HD INF failed therapy and required either dose escalation or alternate medication for disease control. Conclusions. INF is beneficial in the treatment of uveitis, and dose escalation up to 4 times above the approved dose is often necessary to achieve disease control in patients with uveitis. Doses < 10 mg/kg every 4 weeks may not be sufficient to control disease.

Chikungunya Virus Disease: An Emerging Challenge for the Rheumatologist.

AbstractChikungunya is caused by an alphavirus that is transmitted to humans via the Aedes species mosquito. Chikungunya is endemic to tropical Africa and South and Southeast Asia, but over the past decade, the geographic distribution of the virus has been expanding rapidly. The disease is characterized by fever and severe polyarthritis, and although symptoms typically resolve within 7 to 10 days, some patients experience persistent arthritis and arthralgias for months to years.In December 2013, the first local transmission of chikungunya virus in the Americas was identified in the Caribbean Island of Saint Martin. Since then, the number of afflicted individuals has spread throughout the Caribbean and Central America, as well as into South America. The United States reported 2788 chikungunya virus disease cases among travelers returning from affected areas in 2014. In addition, 11 locally acquired cases were reported in Florida. Further spread and establishment of the disease in the Americas are likely considering the high levels of viremia in infected individuals, widespread distribution of effective vectors, lack of immunity among people living in the Americas, and the popularity of international travel.Considering the prominent rheumatic manifestations of chikungunya, rheumatologists are likely to encounter patients with the disease in their practice. We recommend that rheumatologists consider chikungunya in their differential diagnosis when evaluating patients presenting with fever and joint pain following travel to a chikungunya endemic area. Early diagnosis would ensure timely management and reduction of polypharmacy and its associated complications. In this article, we briefly describe the epidemiology of chikungunya, the clinical features, laboratory testing, prevention, and treatment of disease.

Acute-onset opioid-induced hyperalgesia in a child with juvenile idiopathic arthritis.

We describe a child with polyarticular juvenile idiopathic arthritis (JIA) presenting with severe diffuse pain refractory to nonsteroidal anti-inflammatory agents and high-dose opioids. Her JIA involved her knees and ankles and was mildly active on etanercept and nonsteroidal anti-inflammatory agents. At presentation, she complained of hip pain progressing to severe diffuse pain and allodynia involving her extremities. No abnormalities were seen in her laboratory parameters and imaging of her lower extremities. After appreciating no substantial benefit by increasing her opioids, her opioids were tapered and discontinued, and this was followed by significant alleviation in her pain, and a diagnosis of opioid-induced hyperalgesia (OIH) was made. Despite reports in adults, the phenomenon of OIH has been reported infrequently in children. To our knowledge, OIH has not been described in children with rheumatologic conditions. We recommend investigating the possibility of OIH when treating a child with JIA and severe refractory pain.

A Child with X-Linked Agammaglobulinemia and Enthesitis-Related Arthritis

X-linked agammaglobulinemia (XLA) is a primary immune deficiency characterized by recurrent bacterial infections and profoundly depressed serum immunoglobulin levels and circulating mature B cells. We describe a 12-year-old boy with XLA and enthesitis-related arthritis (ERA). To date, there has been a paucity of reports of noninfectious inflammatory arthritis in children with XLA. This case illustrates that functional B cells and/or immunoglobulin are not required for ERA pathogenesis. In addition, this case suggests a possible link between immune deficiency, immune dysregulation, and rheumatic illness.

Single-cell antibody nanowells: a novel technology in detecting anti-SSA/Ro60- and anti-SSB/La autoantibody-producing cells in peripheral blood of rheumatic disease patients

BackgroundAnti-SSA/Ro60 and anti-SSB/La are essential serological biomarkers for rheumatic diseases, specifically Sjögren’s syndrome (SS) and systemic lupus erythematosus (SLE). Currently, laboratory detection technology and platforms are designed with an emphasis on high-throughput methodology; therefore, the relationship of sensitivity with specificity remains a significant area for improvement. In this study, we used single-cell antibody nanowells (SCAN) technology to directly profile individual B cells producing antibodies against specific autoantigens such as SSA/Ro60 and SSB/La.MethodsPeripheral blood mononuclear cells were isolated using Ficoll gradient. Fluorescently labeled cells were added to fabricated nanowells and imaged using a high-speed epifluorescence microscope. The microengraving process was conducted using printed slides coated with immunoglobulins. Printed slides were hybridized with fluorescence-conjugated immunoglobulin G (IgG), SSA/Ro60, and SSB/La antigens. Microarray spots were analyzed for nanowells with single live B cells that produced antigen-specific autoantibodies.ResultsOur results indicate that SCAN can simultaneously detect high frequencies of anti-SSA/Ro60 and anti-SSB/La with a specific IgG isotype in peripheral blood mononuclear cells of patients, as well as measure their individual secretion levels. The data showed that patients with SS and SLE exhibited higher frequency and greater concentration of anti-SSA/Ro60- and anti-SSB/La-producing B cells in the IgG isotype. Furthermore, individual B cells of patients produced higher levels of IgG-specific anti-SSA/Ro60 autoantibody, but not IgG-specific anti-SSB/La autoantibody, compared with healthy control subjects.ConclusionsThese results support the application of SCAN as a robust multiparametric analytical bioassay that can directly measure secretion of autoantibody and accurately report antigen-specific, autoantibody-producing cells.

Hemophagocytic Lymphohistiocytosis Secondary to Ehrlichiosis in a Child

Hemophagocytic lymphohistiocytosis (HLH) is a distinct life threatening clinical entity characterized by fever, pancytopenia, splenomegaly, and hemophagocytosis in bone marrow, liver, or lymph nodes. It is a syndrome of excessive inflammation and tissue destruction due to abnormal immune activation and prompt initiation of treatment is essential for the survival. HLH may be (a) primary due to a familial inheritance of autosomal recessive genes encoding for perforin, Munc 13-4, Munc 18-2, and syntaxin 11 proteins or (b) secondary to infections, malignancy, autoimmune conditions. The association between HLH and infections are important because HLH may mimic infectious illnesses and HLH may obscure the diagnosis of a precipitating, treatable infectious illness. We present a child with secondary HLH but whose illness was triggered by infection with Ehrlichia chaffeensis. The child was treated with doxycycline and for HLH and fully recovered. Genetic testing revealed that child had a compound heterozygous mutation of the PRF-1 and UNC13D, which encode for perforin and Munc 13-4 genes. This case emphasizes the importance of a considering ehrlichiosis as a potential trigger of HLH in children.

Single-cell analysis reveals sexually dimorphic repertoires of Interferon-γ and IL-17A producing T cells in salivary glands of Sjögren’s syndrome mice

The development of Sjögren’s syndrome (SjS) is a dynamic and temporal process with a female predilection. Following the initial influx of immune cells, T cell clusters develop, accelerating the pathology in the salivary glands. Proinflammatory cytokines, IFN-γ and IL-17A, produced by T cells contribute synergistically to the disease. In this study, we examined the sexual dimorphism in cellular infiltrates of the salivary glands by using functional single-cell microengraving analysis. Using high-throughput sequencing, we investigated the clonal diversity of the T cell receptors (TCRs) of infiltrating IFN-γ and IL-17A-producing T cells in male and female SjS-susceptible (SjSs) C57BL/6.NOD-Aec1Aec2 mice. There were elevated frequencies of IFN-γ and IL-17A-producing effector T cell populations in female SjSS mice compared to male SjSS mice. MEME analysis shows high frequency and unique, sexually dimorphic motifs in the TCR hypervariable regions in the SjSS mice. Male mice selected for TRAV8/TRAJ52 (CATDLNTGANTGKLTFG) TCR genes in Th1 cells and TRBV16/(TRBD1/2)TRBJ1-7 (CGGKRRLESIFR) in Th1 and Th17 cells. Female SjSS mice selected for TRAV8/TRAJ52 (CATDLNTGANTGKLTFG), TRAV13D-2/TRAJ23 (CVYLEHHFE), and TRBV23/(TRBD2)TRBJ2-2 (CRKLHSCATCALNFL) in Th1 cells. These findings suggest that there is an elevated prevalence of pathogenic effector T cells in the glands with a sexually dimorphic selection bias of TCR repertoires.

Beyond the Glands: An in-Depth Perspective of Neurological Manifestations in Sjögren's Syndrome.

Primary Sjögren’s Syndrome (pSjS) is an autoimmune disease characterized by sicca (xerophthalmia or xerostomia) symptoms, anti-SS-A (Ro) or anti-SS-B (La) autoantibodies, and lymphocytic infiltrates in the exocrine glands. Disease incidence is estimated to be 0.1–3% of the general population with 0.4–3.1 million individuals in the US with women being nine times more likely to be afflicted with SjS than men. The frequency continues to rise accompanied with the multi-factorial etiology making it a challenging disease to manage and treat. Treatment of this disease remains problematic due to the lack of therapeutic treatments relying on replacement therapies such as artificial saliva and eye lubricants or immunosuppressive agents. To further complicate the management of the disease, there are number of multi-systemic manifestations specifically peripheral neuropathy associated with later stage of disease onset. Increasingly, there is mounting evidence that suggests the involvement of central nervous system. It remains to be determined the underlying cause and effect of the dysregulated immune response and the neuropathy associated with SjS. In this review, we provided an in-depth look at key neurological dysfunctions documented to occur in pSjS. Specifically, we discussed the prevalence, symptomology, and current treatments.

Unique glandular ex-vivo Th1 and Th17 receptor motifs in Sjögren's syndrome patients using single-cell analysis

Primary Sjögrens syndrome (pSS) is an autoimmune disease in which the underlying cause has yet to be elucidated. The main objective of this study was to determine the T cell receptor (TCR) repertoires of individual infiltrating T helper (Th)-1 and 17 cells of pSS patients using single-cell analysis. Single-cell analysis of ex-vivo infiltrating T cells demonstrated that pSS patients had higher frequencies of activated Th17 cells. Single-cell TCR sequencing revealed that TCRβ variable (TRBV)3-1/joint (J)1-2 (CLFLSMSACVW) and TRBV20-1/J1-1 (SVGSTAIPP*T) were expressed by activated Th1 and Th17 cells in both cohorts. Uniquely, TCRα variable (TRAV)8-2/J5 (VVSDTVLETAGE) was expressed by Th1 cells present only in patients and complementarity-determining region (CDR)3α-specific motif (LSTD*E) present in both Th1/Th17 cells. The study demonstrates that both activated Th1 and Th17 cells of pSS patients showed restricted clonal diversities of which two CDR3 motifs were present in controls and patients, with another two motifs unique to pSS.

Infantile-Onset Fever and Urticaria

A 5-year-old white girl presented with a history of recurrent fevers and urticaria since 2 months of age. The child had fevers (maximum temperature, 40°C) that lasted 3 to 5 days. Her mother reported that the fevers resolved spontaneously but continued to recur almost every month. The fever symptoms were associated with bilateral conjunctivitis, arthralgias, and irritability. The hivelike, nonpruritic urticaria did not improve with antihistamine medication and there were no known precipitating or aggravating factors. The child did not attend day care. Family history was noncontributory and her parents denied consanguinity. The child was hospitalized on multiple occasions during infancy for the fevers, and she had comprehensive sepsis evaluations, including lumbar punctures, with negative results. Findings from chest and abdominal imaging and bone marrow aspiration with biopsy were negative for a malignant process. Despite extensive evaluation, a definitive source for the fevers was not identified, and the patient was referred to our institution. On physical examination, the patient was febrile (temperature, 39°C) and appeared fussy. Growth measure findings were normal. Skin examination confirmed nonpruritic, macular and urticarial lesions on the face, back, and lower extremities (Figure). Bilateral conjunctival hyperemia without drainage was noted. There was neither swelling nor redness of the joints. Her right ankle and knee examination showed limited active and passive range of motion secondary to pain symptoms. Findings from the remainder of physical examination were normal.