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The association between the use of certain medications (including sulfonamides, hydralazine, and procainamide) and the occurrence of drug-induced lupus or hepatitis is well established. More recently, cases of immune-related adverse events ranging from inflammatory polyarthritis to necrotizing myositis in patients taking checkpoint inhibitors have been reported. However, data linking drugs to systemic vasculitis are scarce and at times debatable. Propylthiouracil, hydralazine, and minocycline have been associated with rare cases of ANCA-associated syndromes, including life-threatening pulmonary-renal syndromes and systemic polyarteritis nodosa-like diseases. Eosinophilic granulomatosis with polyangiitis (EGPA) has been reported in patients taking leukotriene inhibitors. Since the link between the use of leukotriene inhibitors and occurrence of EGPA remains highly controversial, we performed a literature review for cases of EGPA in patients taking montelukast without prior history of oral corticosteroid use. We found 24 cases, along with our own two cases described, making 26 cases in total. The mean age was 43 and a majority (18/26) were female. In majority of cases EGPA-like disease never relapsed after they were taken off leukotriene inhibitors suggesting a clear causal relationship between the use of these drugs and occurrence of eosinophil-rich systemic EGPA.
Subject(s)
Acetates , Cyclopropanes , Leukotriene Antagonists , Quinolines , Sulfides , Humans , Quinolines/adverse effects , Quinolines/therapeutic use , Acetates/adverse effects , Acetates/therapeutic use , Leukotriene Antagonists/adverse effects , Leukotriene Antagonists/therapeutic use , Female , Churg-Strauss Syndrome/chemically induced , Male , Granulomatosis with Polyangiitis/drug therapy , Granulomatosis with Polyangiitis/chemically induced , Middle Aged , AdultABSTRACT
Immune dysfunction can manifest in unexpected ways. We present the case of a patient with systemic lupus erythematosus (SLE) in whom the first sign of disseminated histoplasmosis and consequent macrophage activation syndrome (MAS) was tongue necrosis. In those with immune dysfunction, a high index of clinical suspicion for atypical infections is warranted.
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BACKGROUND Remitting seronegative symmetrical synovitis with pitting edema (RS3PE) is a rare condition with underlying polyarthritis, pitting edema, and negative rheumatoid factor. It can be associated with an underlying rheumatological condition or can present as a paraneoplastic syndrome with malignancy. We present a rare case of RS3PE associated with monoclonal gammopathy of undermined significance (MGUS). CASE REPORT A 62-year-old man presented in ambulatory medicine clinic with 3-month swelling of distal lower extremities that progressed to distal upper extremities. He had pain and morning stiffness in hands, left elbow, and left shoulder. Examination revealed 3+ pitting edema in bilateral hands, feet, legs, and thighs. Laboratory studies revealed normal blood counts and renal and liver functions. Erythrocyte sedimentation rate was normal; C-reactive protein was mildly elevated (0.7 mg/dL). Echocardiogram and computed tomography of chest, abdomen, and pelvis revealed mild splenomegaly (14.5 cm). Serum protein electrophoresis revealed IgG kappa monoclonal peak of 0.1 g/dL. Beta-2 microglobulin was elevated (7.4 mg/L); LDH was elevated (264 U/L). No lytic lesions were present in bones. RS3PE was diagnosed based on established diagnostic criteria. Prednisone produced significant improvement in swelling within 72 h of start; however, he required a longer duration of steroid treatment due to relapse and continued periodic MGUS surveillance. CONCLUSIONS Our case highlights the importance of awareness of this condition in general practice to help with timely diagnosis and intervention, as this condition is steroid responsive. Also, it is important to screen for underlying autoimmune condition, hematological, and solid organ malignancies with appropriate workup.
Subject(s)
Arthritis , Monoclonal Gammopathy of Undetermined Significance , Synovitis , Male , Humans , Middle Aged , Synovitis/diagnosis , Synovitis/drug therapy , Synovitis/complications , Edema/etiology , Prednisone , Antibodies, MonoclonalABSTRACT
Discovery of antinuclear antibodies (ANA) enabled earlier diagnosis of systemic lupus erythematosus (SLE) and other ANA+ connective tissue diseases (CTD). Rheumatologists increasingly encounter high referral volume of ANA+ patients. It has been estimated that only a small percentage of these patients will eventually transition to either SLE or other specified CTD. Incomplete lupus erythematosus (ILE) has been defined as a subset of patients who have some SLE-specific clinical manifestations but do not meet currently accepted classification criteria for SLE. Several studies have been performed with the goal of identifying clinical features, serum and tissue biomarkers that can distinguish those patients with ILE at risk of transitioning to SLE from those who will not. Increased autoantibody diversity, presence of anti-double-stranded DNA (dsDNA) antibodies, high expression of type I and type II interferon (IFN)-gene products, increased serum levels of B-cell-activating factor of the TNF family (BAFF), and certain serum cytokines and complement products have been identified as markers with positive predictive value, particularly when combined together. Once this patient population is better characterized biochemically, clinical trials should be considered with the primary objective to completely halt or slow down the transition from ILE to SLE. Hydroxychloroquine (HCQ) appears to be a promising agent due to its good tolerability and low toxicity profile and open-label studies in ILE patients have already shown its ability to delay the onset of SLE. Other therapeutics, like those targeting abnormal type I and type II IFN-signatures, B-cell specific signaling pathways, complement activation pathways and high BAFF levels should also be evaluated, but the risk to benefit ratio must be carefully determined before they can be considered.
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ABSTRACT: Clinicians usually easily recognize cranial manifestations of giant cell arteritis (GCA) such as new-onset headache, jaw claudication, scalp tenderness, and abrupt changes in visual acuity or blindness; however, when presented with an aberrant clinical course, the diagnosis becomes more elusive. In addition to temporal arteries and other extracranial branches of the carotid arteries, large vessel vasculitis (LVV) can also affect other blood vessels including coronary arteries, aorta with its major branches, intracranial blood vessels, and hepatic arteries.Over time, the scope of the symptoms typically associated with LVV has broadened and includes cases of fever of unknown origin accompanied with other constitutional symptoms that can mimic a range of neoplastic and infectious diseases. In up to half of patients with atypical LVV, liver enzyme level elevations with a cholestatic pattern have been observed. Alkaline phosphatase level and γ-glutamyl transferase level elevations tend to be more prevalent in those LVV patients with vigorous inflammatory responses, particularly in those with fever and other nonspecific constitutional symptoms. These patients also have more profound anemia and thrombocytosis. With the exception of rare instances of vasculitides and granulomas affecting the liver tissue, liver biopsy is generally of little help and primarily shows nonspecific changes of fatty liver.In this article, we review 3 patients who were eventually diagnosed with atypical LVV. The diagnosis was confirmed with temporal artery biopsy in 2 patients and with positron emission tomography/computed tomography in 1 patient. The common hepatic abnormality observed in all patients was the elevation of alkaline phosphatase level, which tended to respond rapidly to initiation of immunosuppressive treatment.
Subject(s)
Giant Cell Arteritis , Aorta , Giant Cell Arteritis/complications , Giant Cell Arteritis/diagnosis , Humans , Liver , Positron Emission Tomography Computed Tomography , Temporal ArteriesSubject(s)
Back Pain/etiology , Hemochromatosis/diagnosis , Osteoarthritis/etiology , Adult , Diagnosis, Differential , Ferritins/blood , Hand/diagnostic imaging , Hemochromatosis/complications , Hemochromatosis/genetics , Humans , Male , Osteoarthritis/diagnostic imaging , Pelvic Bones/diagnostic imaging , Transferrin/analysisABSTRACT
BACKGROUND: Treatment of rheumatoid arthritis (RA) often involves immune-suppressive therapies. Concern for recurrent prosthetic joint infection (PJI) in RA patients might be high and could reduce use of joint implantation in these patients. We aimed to evaluate the risk of recurrence of PJI in RA patients compared with osteoarthritis (OA) patients by utilizing a large health care system. METHODS: We conducted a retrospective cohort study of all patients admitted for a Staphylococcus aureus PJI who underwent debridement, antibiotics, and implant retention (DAIR) or 2-stage exchange (2SE) between 2003 and 2010 at 86 Veterans Affairs Medical Centers. Both RA patients and the comparison group of osteoarthritis (OA) patients were identified using International Classification of Diseases, Ninth Revision, codes. All index PJI and recurrent positive cultures for S. aureus during 2 years of follow-up were validated by manual chart review. A Cox proportional hazards regression model was used to compare the time to recurrent PJI for RA vs OA. RESULTS: In our final cohort of 374 veterans who had either DAIR or 2SE surgery for their index S. aureus PJI, 11.2% had RA (n = 42). The majority of the cohort was male (97.3%), and 223 (59.6%) had a methicillin-susceptible S. aureus PJI. RA patients had a similar risk of failure compared with OA patients, after adjusting for covariates (hazard ratio, 0.81; 95% confidence interval, 0.48-1.37). CONCLUSIONS: Prior diagnosis of RA does not increase the risk of recurrent S. aureus PJI. Further studies are needed to evaluate the effect of different RA therapies on outcomes of episodes of PJI.
Subject(s)
Antibodies, Monoclonal/therapeutic use , Antineoplastic Agents/therapeutic use , Arthritis/chemically induced , Arthritis/drug therapy , Immunotherapy/methods , Nivolumab/adverse effects , Programmed Cell Death 1 Receptor/immunology , Adult , Antibodies, Monoclonal/pharmacology , Antibodies, Monoclonal, Humanized , Antineoplastic Agents/pharmacology , Arthritis/pathology , Humans , Male , Young AdultABSTRACT
INTRODUCTION: Hydralazine is an antihypertensive medication that has been associated with drug-induced lupus erythematosus (DIL) as well as ANCA-associated vasculitis (AAV). Although rare, early diagnosis is critical since drug cessation is the mainstay of therapy. This retrospective study aims to characterize the clinical, laboratory, and histopathologic features of this disease. METHODS: Once approval was obtained from the Institutional Review Board at the University of Iowa, all patients carrying a diagnosis of vasculitis (ICD9 code: 447.6 or ICD10 code: I77.6, I80, L95, M30, or M31) and positive ANCA lab results over the past 15 years were identified. Age, gender, comorbid conditions, medications taken over the prior 6 months, laboratory data, including electrolytes, urine studies and serologies, chest x-rays, CT scans, and pathologic biopsy records were abstracted from the electronic medical record. RESULTS: 323 cases of AAV were identified, of which 12 were exposed to hydralazine, all at the time of diagnosis. The average duration of hydralazine therapy was 22 months and mean cumulative dose was 146g. Patients were typically older (70.3 years old) with slight female preponderance (7 females). Eleven patients presented with dyspnea, fatigue, and unintentional weight loss. Five had polyarthralgias and 8 had lower extremity petechiae. All 12 patients were both ANA and ANCA positive. ANA titers ranged from 1:160 and 1:2560. Ten were of diffuse pattern while 2 were nucleolar. ANCA titers ranged from 1:320 to 1:2560. Eleven had a pANCA pattern while one had cANCA. All 12 patients were positive for histone and 11 were positive for myeloperoxidase antibodies. Eleven also had dsDNA antibodies, and 4 had anti-cardiolipin IgG or IgM antibodies. Nine patients were also hypocomplementemic (mean C3 level: 88.4mg/dL; mean C4 level: 16.5mg/dL). All patients had variable levels of proteinuria (1+ to 3+) and eleven had active urine sediment. Urine protein:creatinine ratios ranged from 0.2 to 1.7. Of the 6 patients who underwent kidney biopsy, all 6 showed pauci-immune crescentic glomerulonephritis. Seven patients had bilateral pulmonary interstitial infiltrates and four had pleural effusions on CT scan. Four had pericardial effusions as demonstrated by echocardiography. CONCLUSIONS: Hydralazine-associated vasculitis is a drug-associated autoimmune syndrome that presents with interstitial lung disease, hypocomplementemia, and pauci-immune glomerulonephritis. Patients have elements of both DIL and DIV, as manifested by high ANA and ANCA titers as well as the presence of histone and MPO antibodies. Further research is needed to understand the etiopathogenesis of this condition.
Subject(s)
Antihypertensive Agents/adverse effects , Hydralazine/adverse effects , Lupus Erythematosus, Systemic/chemically induced , Vasculitis/chemically induced , Aged , Antibodies, Antineutrophil Cytoplasmic/blood , Female , Humans , Lupus Erythematosus, Systemic/immunology , Male , Retrospective Studies , Vasculitis/immunologyABSTRACT
Joint hypermobility syndrome, also known as benign hypermobility syndrome, is a connective tissue disease characterized by joint instability, chronic pain, and minor skin changes. It shares many clinical features of Ehlers-Danlos syndrome, Hypermobility Type; enough so that many authorities consider them as one disease process. Approximately 3% of the general population is believed to have joint hypermobility syndrome, but despite this high prevalence, due to lack of awareness, heterogeneity of clinical presentation, and reliance on physical examination for diagnosis, it is largely overlooked by primary care physicians as well as by specialists. This leads to delayed or missed opportunities for diagnosis, and inappropriate interventions that frustrate both providers and patients. We review the literature regarding the pathophysiology, diagnosis, treatment options, and prognosis of joint hypermobility syndrome, and advocate for primary care physicians to consider it in the differential diagnosis of patients with chronic pain.
Subject(s)
Chronic Pain/etiology , Ehlers-Danlos Syndrome/diagnosis , Abdominal Pain/etiology , Ehlers-Danlos Syndrome/epidemiology , Ehlers-Danlos Syndrome/physiopathology , Ehlers-Danlos Syndrome/therapy , Fatigue/etiology , Headache/etiology , Humans , Mitral Valve Prolapse/etiology , Musculoskeletal Pain/etiology , Pelvic Pain/etiology , Prevalence , Primary Dysautonomias/etiologyABSTRACT
B cells in general and BAFF (B cell activating factor of the tumor necrosis factor [TNF] family) in particular have been primary targets of recent clinical trials in systemic lupus erythematosus (SLE). In 2011, belimumab, a monoclonal antibody against BAFF, became the first biologic agent approved for the treatment of SLE. Follow-up studies have shown excellent long-term safety and tolerability of belimumab. In this review, we critically analyze blisibimod, a novel BAFF-neutralizing agent. In contrast to belimumab that only blocks soluble BAFF trimer but not soluble 60-mer or membrane BAFF, blisibimod blocks with high affinity all three forms of BAFF. Furthermore, blisibimod has a unique structure built on four high-affinity BAFF-binding peptides fused to the IgG1-Fc carrier. It was tested in phase I and II trials in SLE where it showed safety and tolerability. While it failed to reach the primary endpoint in a recent phase II trial, post hoc analysis demonstrated its efficacy in SLE patients with higher disease activity. Based on these results, blisibimod is currently undergoing phase III trials targeting this responder subpopulation of SLE patients. The advantage of blisibimod, compared to its competitors, lies in its higher avidity for BAFF, but a possible drawback may come from its immunogenic potential and the anticipated loss of efficacy over time.
Subject(s)
Lupus Erythematosus, Systemic/drug therapy , Recombinant Fusion Proteins/therapeutic use , B-Cell Activating Factor/antagonists & inhibitors , B-Cell Activating Factor/metabolism , Humans , Lupus Erythematosus, Systemic/metabolism , Recombinant Fusion Proteins/pharmacologyABSTRACT
Optimal rheumatoid arthritis (RA) therapy in daily clinical practice is based on the treat-to-target strategy. Quicker escalation of therapy and earlier introduction of biological disease-modifying anti-rheumatic drugs have led to improved outcomes in RA. However, chronic immunosuppressive therapy is associated with adverse events and higher costs. In addition, our patients frequently express a desire for lower dosing and drug holidays. Current clinical practice guidelines from the American College of Rheumatology and European League Against Rheumatism suggest that rheumatologists consider tapering treatment after achieving remission. However, the optimal approach for tapering therapy in RA, specifically de-escalation of biologics, remains unknown. This clinical review discusses biologic tapering strategies in RA. We draw our recommendations for everyday clinical practice from the most recent observational, pragmatic, and controlled clinical trials on de-escalation of biologics in RA. For each biologic, we highlight clinically relevant outcomes, such as flare rates, recapture of the disease control with retreatment, radiographic progression, side effects, and functional impact. We discuss the use of musculoskeletal ultrasound to select patients for successful tapering. In conclusion, we provide the reader with a practical guide for tapering biologics in the rheumatology clinic.
Subject(s)
Arthritis, Rheumatoid/drug therapy , Biological Products/administration & dosage , Rheumatology/methods , Abatacept/administration & dosage , Adalimumab/administration & dosage , Antibodies, Monoclonal, Humanized/administration & dosage , Antirheumatic Agents/administration & dosage , Certolizumab Pegol/administration & dosage , Drug Administration Schedule , Etanercept/administration & dosage , Humans , Immunosuppressive Agents/therapeutic use , Infliximab/administration & dosage , Muscle, Skeletal/diagnostic imaging , Tumor Necrosis Factor-alpha/antagonists & inhibitors , UltrasonographyABSTRACT
Physicians caring for patients with Behcet's should be aware of the potential complication of uveitis with hypopyon in these patients, and the condition warrants prompt management.
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African Americans are more likely to suffer from gout and are less likely to receive optimal treatment for it. Physicians should be aware of risk factors for gout and professional guidelines for treating acute attacks and high uric acid levels, and should help develop strategies to reduce disparities in healthcare delivery.
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Gout Suppressants/pharmacology , Gout , Black or African American , Gout/diagnosis , Gout/ethnology , Gout/therapy , Healthcare Disparities , Humans , Medication Therapy Management , Practice Guidelines as Topic , Uric Acid/analysisABSTRACT
B cells play an important role in systemic lupus erythematosus by acting not only as precursors of autoantibody-producing cells but also as antigen-presenting, cytokine-secreting, and regulatory cells. Unopposed activation of B cells through their B-cell receptor for antigen, as seen in B cells lacking Lyn kinase, results in systemic autoimmunity. The B-cell activating factor of the TNF family (BAFF), nucleic acid-sensing Toll-like receptors (TLRs), and type I interferon can affect B-cell survival and decrease their threshold for activation. Herein we discuss both direct and indirect strategies aimed at targeting B cells in patients with lupus by blocking BAFF, type I interferon, or TLR7 to TLR9. Although BAFF-depleting therapy with belimumab achieved approval for lupus, other BAFF inhibitors were much less beneficial in clinical trials. Inhibitors of the B-cell receptor for antigen signaling and antibodies against type I interferon are in the pipeline. The TLR7 to TLR9 blocker hydroxychloroquine has been in use in patients with lupus for more than 50 years, but oligonucleotide-based inhibitors of TLR7 to TLR9, despite showing promise in animal models of lupus, have not reached the primary end point in a recent phase 1 trial. These data point toward possible redundancies in B-cell signaling/survival pathways, which must be better understood before future clinical trials are executed.
Subject(s)
B-Lymphocytes/immunology , Lupus Erythematosus, Systemic/immunology , Agammaglobulinaemia Tyrosine Kinase , Animals , B-Cell Activating Factor/immunology , Humans , Interferon Type I/immunology , Protein-Tyrosine Kinases/antagonists & inhibitors , Syk Kinase/antagonists & inhibitors , Toll-Like Receptors/antagonists & inhibitors , Toll-Like Receptors/immunology , Tumor Necrosis Factor Ligand Superfamily Member 13/immunologyABSTRACT
A 46-year-old female with interstitial lung disease presented with proximal muscle weakness, worsening hypertension, microangiopathic hemolysis, thrombocytopenia and deteriorating renal function. She had no sclerodactyly, but had abnormal capillaroscopy. She tested positive for PM-Scl antibodies, and a renal biopsy showed an acute thrombotic microangiopathy consistent with scleroderma renal crisis (SRC). She failed to respond to corticosteroids, plasmapheresis and renin-angiotensin pathway inhibitors. She recovered quickly with the anti-C5 antibody, eculizumab. She had no genetic abnormalities associated with atypical hemolytic uremic syndrome except a DNA variant of unknown significance in C3. This case suggests that eculizumab may be effective for SRC.
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Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) comprises several clinical entities with diverse clinical presentations, outcomes, and nonunifying pathogenesis. AAV has a clear potential for relapses, and shows unpredictable response to treatment. Cyclophosphamide-based therapies have remained the hallmark of induction therapy protocols for more than four decades. Recently, B-cell depleting therapy with the anti-CD20 antibody rituximab has proved beneficial in AAV, leading to Food and Drug Administration approval of rituximab in combination with corticosteroids for the treatment of AAV in adults. Rituximab for ANCA-associated vasculitis and other clinical trials provided clear evidence that rituximab was not inferior to cyclophosphamide for remission induction, and rituximab appeared even more beneficial in patients with relapsing disease. This raised hopes that other B-cell-targeted therapies directed either against CD19, CD20, CD22, or B-cell survival factors, B-cell activating factor of the tumor necrosis factor family (BAFF) and a proliferation-inducing ligand could also be beneficial for the management of AAV. BAFF neutralization with the fully humanized monoclonal antibody belimumab has already shown success in human systemic lupus erythematosus and, along with another anti-BAFF reagent blisibimod, is currently undergoing Phase II and III clinical trials in AAV. Local production of BAFF in granulomatous lesions and elevated levels of serum BAFF in AAV provide a rationale for BAFF-targeted therapies not only in AAV but also in other forms of vasculitis such as Behcet's disease, large-vessel vasculitis, or cryoglobulinemic vasculitis secondary to chronic hepatitis C infection. BAFF-targeted therapies have a very solid safety profile, and may have an additional benefit of preferentially targeting newly arising autoreactive B cells over non-self-reactive B cells.
Subject(s)
Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/drug therapy , Antibodies, Monoclonal, Humanized/therapeutic use , B-Cell Activating Factor/antagonists & inhibitors , B-Lymphocytes/drug effects , Drug Discovery/methods , Immunosuppressive Agents/therapeutic use , Molecular Targeted Therapy/methods , Tumor Necrosis Factor Ligand Superfamily Member 13/antagonists & inhibitors , Animals , Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/diagnosis , Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/immunology , Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis/metabolism , B-Cell Activating Factor/immunology , B-Cell Activating Factor/metabolism , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Humans , Signal Transduction/drug effects , Treatment Outcome , Tumor Necrosis Factor Ligand Superfamily Member 13/immunology , Tumor Necrosis Factor Ligand Superfamily Member 13/metabolismABSTRACT
Minocycline is a synthetic tetracycline-derived antibiotic with significant anti-inflammatory properties that may benefit patients with rheumatoid arthritis. Surprisingly, chronic exposure to minocycline can also cause a breach in immunologic tolerance resulting in a variety of autoimmune syndromes such as drug-induced lupus or autoimmune hepatitis. Vasculitis, most commonly resembling cutaneous polyarteritis nodosa, has also been seen in patients taking this drug. Herein, we present a case of biopsy-proven systemic vasculitis presenting as an ANA (+) ANCA (+) polyarteritis nodosa-like syndrome in a male patient who was taking minocycline for his acne for approximately 2 years. Patient initially presented with constitutional symptoms such as profound weight loss and fatigue, along with myalgias, oligoarticular arthritis, and livedo reticularis. About 2 months later, he developed a severe left testicular pain. Biopsy showed vasculitis complicated with the infarction of the left testis. Angiography revealed microaneurysms in the renal and splenic circulation. Stopping the offending drug, along with the short course of prednisone and hydroxychloroquine, resulted in prompt resolution of his symptoms. We additionally present a comprehensive review of biopsy-proven cases of vasculitis associated with chronic minocycline treatment focusing on its pathogenesis and clinical manifestations.
Subject(s)
Antibodies, Antineutrophil Cytoplasmic/blood , Minocycline/adverse effects , Neutrophils/immunology , Systemic Vasculitis/blood , Systemic Vasculitis/chemically induced , Acne Vulgaris/complications , Acne Vulgaris/drug therapy , Angiography , Autoimmunity/immunology , Biopsy , Diagnosis, Differential , Humans , Hydroxychloroquine/administration & dosage , Inflammation , Male , Polyarteritis Nodosa/diagnosis , Prednisone/administration & dosage , Systemic Vasculitis/complications , Testis/pathology , Young AdultABSTRACT
Type I allergic diseases, such as allergic rhinitis and asthma, depend on allergen-induced T-helper type 2 (Th2) cells and IgE-secreting plasma cells. Fortunately, this harmful immune response can be modified by engaging Toll-like receptor (TLR)7 and TLR9, offering hopes to allergy sufferers. While clinical trials employing synthetic ligands for TLR7 or TLR9 are under way, one can wonder whether TLR7 or TLR9 engagements may trigger inadvertent autoreactivity and/or Th1-/Th17-mediated tissue pathology. To neutralize such danger, we have pioneered the development of potent TLR9 pathway antagonists, inhibitory oligonucleotides (INH-ODNs), which work in a sequence-specific manner. Interestingly, INH-ODNs also have TLR7-inhibitory properties; however, these effects appear to be sequence independent and phosphorothioate backbone dependent. In B cells, co-engagement of the B-cell receptor for antigen and TLR7 or TLR9 may influence how INH-ODNs impose their regulatory effects. INH-ODNs block TLR9 activation by competitively antagonizing ligand binding to proteolytically cleaved C-terminal TLR9 fragment. One may envision future use of INH-ODNs in systemic autoimmune diseases, DNA-mediated sepsis, or other situations in which chronic inflammation results from abnormal TLR7- and/or TLR9-mediated immune activation.