Propylthiouracil-Induced Autoimmune Syndromes: Two Distinct Clinical Presentations with Different Course and Management

Drug-Induced Renal Vasculitis: Etiology, Pathogenesis, Clinical Manifestations, and Therapeutic Approaches-A Narrative Review

Background and Aims

Drug-induced renal vasculitis arises from various medications that cause immunological dysregulation or direct vascular damage, leading to inflammation and thrombosis. Clinical manifestations vary widely, from mild constitutional symptoms to severe organ dysfunction. This review aims to thoroughly explore drug-induced renal vasculitis, focusing on its etiology, pathological mechanisms, clinical manifestations, diagnostic challenges, and therapeutic approaches. This review aims to summarize current knowledge and highlight areas requiring further research.

Methods

A comprehensive literature search was conducted using PubMed, MEDLINE, Embase, and Cochrane Library databases. We included peer-reviewed journal articles and excluded those with insufficient data, poor quality, or lack of relevance. The search terms included combinations of "renal vasculitis," "drug-induced vasculitis," "drug-related nephritis," "medication-induced renal vasculitis," and specific drug names. An initial search yielded 13,192 articles, of which 13,103 were excluded due to irrelevance, duplication, or outdated information. After full-text review, 99 peer-reviewed articles were included.

Results

Discontinuation of the offending drug is the primary and most crucial step in managing drug-induced renal vasculitis. Prognosis is generally more favorable than primary vasculitis, with a high remission rate if the offending drug is stopped early. Due to its rarity, epidemiological data is limited. Diagnosis frequently relies on autoantibodies [antineutrophil cytoplasm antibodies (ANCA), myeloperoxidase (MPO), antinuclear antibody (ANA)] and clinical symptoms, with renal biopsy confirming it. Factors such as high-dose and long-term drug use, as well as genetic predispositions, increase the risk.

Conclusion

This review provides a comprehensive overview of drug-induced renal vasculitis, discussing what is known and identifying gaps in understanding. While discontinuing the causative drug remains the cornerstone of management, further research is needed, particularly in developing a formal tool to assess the quality of studies and minimize selection bias.

An Unusual Presentation of Propylthiouracil-Induced Immunoglobulin A Vasculitis With Positive Anti-proteinase-3 and Anti-myeloperoxidase Antibodies

Propylthiouracil (PTU) has been identified as a known cause of anti-neutrophil cytoplasmic antibodies-associated vasculitis. However, the association between PTU and immunoglobulin A (IgA) vasculitis remains uncertain due to its rarity and diverse clinical presentation. Here, we report the case of a 57-year-old female with a past medical history of chronic leukopenia and Graves' disease treated with PTU that presented with pancytopenia and widespread non-blanching ecchymoses on the bilateral legs. A punch biopsy of the medial leg demonstrated IgA vasculitis and autoimmune antibody analysis revealed increased levels of anti-proteinase 3 antibodies compared to anti-myeloperoxidase antibodies. These findings led to the diagnosis of PTU-induced IgA vasculitis. Following the discontinuation of PTU, there was marked improvement in the appearance of the patient's cutaneous manifestations and hematological indices.

Vasculitis-like Palpable Purpuric Rash Induced by Decapeptyl in a Pediatric Patient Diagnosed Central Precocious Puberty

Central precocious puberty (CPP) is defined as the appearance of secondary sexual signs in girls younger than eight years of age or the onset of menarche before the age of 10 years. Gonadotropin-releasing hormone analogs (GnRHa) are the most effective therapy in CPP. Drug-induced hypersensitivity vasculitis is an inflammation of blood vessels, which may be due to the use of a number of pharmacologic agents. This case report describes drug-induced vasculitis in a girl being treated with Decapeptyl. A 7.25 year-old girl was admitted to Pediatric Endocrinology outpatients with premature breast development. She was diagnosed with CPP on the basis of physical examination and laboratory findings and tripoteline acetate (Decapeptyl®) treatment was initiated. She experienced multiple widespread skin rashes and mild abdominal pain with high temperature eight hours after the second dose of Decapeptyl. She was admitted to hospital with the diagnosis of drug-induced vasculitis and a single dose of intravenous methyl-prednisolone (1 mg/kg) and oral cetirizine was given. Her blood and urine analysis revealed no other organ involvement, other than skin. On the third day, the purpuric lesions began to resolve and had completely disappeared by the sixth day. Her treatment for CPP was switched to Depot Leuprolide acetate and she continued her treatment for two years uneventfully. To the best of our knowledge, this is the first report of a child with CPP experiencing drug-induced vasculitis due to tripotelin injection. Effective treatment may be continued by switching to an alternative gonadotropin releasing hormone analog.

Drug-induced anti-neutrophil cytoplasmic antibody-associated vasculitis

OBJECTIVE

In recent years, an increasing number of drugs have been proved to be associated with the induction of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). This article reviews the latest research progress on drug-induced AAV.

DATA SOURCES

We conducted a comprehensive and detailed search of the PubMed database. The search terms mainly included drug-induced, ANCA, and vasculitis.

STUDY SELECTION

We summarized the original articles and reviews on drug-induced AAV in recent years. The extracted information included the definition, epidemiology, associated drugs, pathogenesis, clinical features, diagnosis, treatment, and prognosis of drug-induced AAV. We also focused on the differences between drug-induced AAV and primary vasculitis.

RESULTS

The offending drugs leading to drug-induced AAV are almost from pharmacologic categories and we need to be vigilant when using these drugs. The pathogenesis of drug-induced AAV might be multifactorial. The formation of neutrophil extracellular traps is an important mechanism for the development of drug-induced AAV. The clinical features of drug-induced AAV are similar to those of primary AAV. Understanding the difference between drug-induced AAV and primary AAV is helpful to identify drug-induced AAV. Stopping the offending drug at once after diagnosis may be sufficient for those patients with mild symptoms. Immunosuppressive therapy should only be used in patients with vital organs involvement.

CONCLUSIONS

Patients with drug-induced AAV usually have a good prognosis if they stop using the offending drug immediately. Recent advances in research on AAV are expected to help us better understand the pathogenesis of drug-induced AAV.

Antithyroid drug induced syndrome that lies in between ANCA vasculitis and lupus-like syndrome in a 40-year-old female with Graves' disease under methimazole therapy: A Case report

We report the case of a 40-year-old Greek female with symptoms of polyarthritis, pruritic rash and positive p-ANCA antibodies, undergoing treatment with Methimazole therapy for Graves’ disease. The rash and the arthritis symptoms promptly disappeared after withdrawal of methimazole, but p-ANCA antibodies remained positive for 6 weeks. By the time that p-ANCA became negative, anti-dsDNA antibodies presented and remained at high titers for 3 months, with no clinical or specific organ disease symptoms. The patient was under close monitoring for the case of potentially life-threating vasculitis of the lung or the kidney and was treated with methylprednisolone. We diagnosed the patient with Antithyroid drug Syndrome, which in our patient presented with arthritis symptoms and had serological features which are commonly found to Antithyroid drug pANCA vasculitis and Antithyroid drug lupus-like syndrome. Physician’s awareness is essential for the diagnosis and treatment of this syndrome in clinical practice, taking into consideration the high frequency of the use of antithyroid agents.

Propylthiouracil-Associated Leukocytoclastic Necrotizing Cutaneous Vasculitis: A Case Report and Review of the Literature

The purpose of this case report and review of the literature is to provide an exploration of the clinical symptoms, diagnosis, prevention, and management of propylthiouracil (PTU)-associated vasculitis in the intensive care setting. A PubMed search of the available literature was conducted using the MeSH search terms "propylthiouracil" and "vasculitis." The literature search returned 121 articles. Twenty-five were excluded because they were not in English. Fifty-nine case reports or case studies describing PTU-associated vasculitis were included. Data extracted from each case study included patient age, sex, autoimmune markers, laboratory tests, length of time on PTU, treatment for vasculitis, and patient outcomes. The authors reviewed 128 cases of PTU-associated vasculitis. The majority were women (8.8:1 F:M ratio), and the most common presenting symptoms were rash (51.6%), fever (46.9%), and arthralgia (43.8%). In addition to discontinuing PTU, the most common treatment was steroids (71.9%). Eight patients (6.3%) progressed to end-stage renal disease; two (1.6%) required intubation for respiratory failure; and five (3.9%) died of various organ systems failure related to vasculitis development. A high index of suspicion for vasculitis should be maintained, especially when presented with skin manifestations in the presence of PTU therapy. Screening with myeloperoxidase-antinuclear cytoplasmic antibodies is most sensitive. Positive screening should prompt a thorough clinical investigation. In cases of severe skin manifestations, the focus should be on aggressive wound care. Our case report is unique, not only in the size and extent of cutaneous involvement, but also as the first description of mortality secondary to cutaneous manifestations.

Propylthiouracil-induced ANCA-negative cutaneous small vessel vasculitis

Propylthiouracil (PTU) is a commonly used medication for the treatment of hyperthyroidism. PTU is known to cause different adverse reactions including autoimmune syndromes. PTU-induced autoimmune syndromes can be classified into drug-induced lupus or drug-induced vasculitis. Differential diagnoses could be very challenging. PTU-induced vasculitis is more common than PTU-induced lupus, and has a higher risk of morbidity and mortality. Usually it is limited to the skin in a form of cutaneous leukocytoclastic vasculitis, but may also affect organs including kidneys and lungs. Discontinuation of PTU should be a first step in the treatment and could lead to complete resolution of symptoms. Typically, lesions resolve spontaneously within 2–4 weeks, but chronic or recurrent disease may occur in up to 10% of patients. In cases without improvement after drug discontinuation, cases refractory to glucocorticosteroids, with necrotizing skin lesions or extracutaneous organ involvement referral to rheumatologist for more aggressive immunosuppressive treatment is indicated. Optimal duration of immunosuppressive therapy is unknown, but it is reasonable to gradually taper mediations and monitor clinical response. Frequent monitoring for side effects is mandatory for patients on PTU therapy. Treatment should be stopped immediately, if patient develops any of autoimmune syndromes. An accurate and prompt diagnosis is essential, because it determines further management. We report a rare case of antineutrophil cytoplasm antibody-negative cutaneous small vessel vasculitis as a result of longstanding exposure to PTU.

Hydralazine-associated vasculitis: Overlapping features of drug-induced lupus and vasculitis

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.

Antithyroid arthritis syndrome

Antithyroid arthritis syndrome is a constellation of symptoms of myalgia, arthralgia, arthritis, fever and rash associated with the use of antithyroid medications. We report a case of a patient with severe hyperthyroidism likely secondary to Graves' disease who presented with the abovementioned symptoms after being treated with methimazole (antithyroid medication). Our aim is to increase awareness regarding this uncommon but disabilitating and life-threatening adverse effect of antithyroid medications among clinicians. We also discuss the proposed pathophysiology for this immunological reaction as well as management options in these patients.

Possibly propylthiouracil-induced antineutrophilic cytoplasmic antibody-associated vasculitis manifested as blood coagulation disorders: A case report

BACKGROUND

Propylthiouracil is the most common drug used to treat hyperthyroidism. However, this drug could cause a severe disease, antineutrophilic cytoplasmic antibody-associated vasculitis (AAV), which was usually misdiagnosed.

METHODS

We reported a 60-year-old woman of propylthiouracil-induced AAV manifested as blood coagulation disorders. The patient was admitted because of hyperthyroidism and leukopenia. At the time of hospitalization, she suffered from dry cough, erythema and knee joints ache, and gradually became febrile. And then BP decreased and PLT was reduced with coagulation disorders. ANCA: c-ANCA positive (1:100), p-ANCA positive (1:320), MPO-IgG positive, PR3-IgG positive, GBM-IgG negative. Erythrocyte sedimentation rate and C-reactive protein increased markedly. Chest high-resolution computed tomography (HRCT) showed that scattered spots, patch and ground-glass opacity.

RESULTS

Finally, we made a terminal diagnosis of PTU-induced AAV possibly. After drug withdrawal and use of steroid, the patient recovered well and then accepted RAI therapy. As the patient was given imipenem-cilastatin before the reduction of PLT and coagulation disorders, we considered that the hematologic disorders might be caused by antibiotics or a clinical presentation of the vasculitis itself.

CONCLUSION

Drug-induced vasculitis is relatively good prognosis, but early diagnosis and timely withdrawal of associated drugs are the key to the treatment.

2016 American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism and Other Causes of Thyrotoxicosis

BACKGROUND

Thyrotoxicosis has multiple etiologies, manifestations, and potential therapies. Appropriate treatment requires an accurate diagnosis and is influenced by coexisting medical conditions and patient preference. This document describes evidence-based clinical guidelines for the management of thyrotoxicosis that would be useful to generalist and subspecialty physicians and others providing care for patients with this condition.

METHODS

The American Thyroid Association (ATA) previously cosponsored guidelines for the management of thyrotoxicosis that were published in 2011. Considerable new literature has been published since then, and the ATA felt updated evidence-based guidelines were needed. The association assembled a task force of expert clinicians who authored this report. They examined relevant literature using a systematic PubMed search supplemented with additional published materials. An evidence-based medicine approach that incorporated the knowledge and experience of the panel was used to update the 2011 text and recommendations. The strength of the recommendations and the quality of evidence supporting them were rated according to the approach recommended by the Grading of Recommendations, Assessment, Development, and Evaluation Group.

RESULTS

Clinical topics addressed include the initial evaluation and management of thyrotoxicosis; management of Graves' hyperthyroidism using radioactive iodine, antithyroid drugs, or surgery; management of toxic multinodular goiter or toxic adenoma using radioactive iodine or surgery; Graves' disease in children, adolescents, or pregnant patients; subclinical hyperthyroidism; hyperthyroidism in patients with Graves' orbitopathy; and management of other miscellaneous causes of thyrotoxicosis. New paradigms since publication of the 2011 guidelines are presented for the evaluation of the etiology of thyrotoxicosis, the management of Graves' hyperthyroidism with antithyroid drugs, the management of pregnant hyperthyroid patients, and the preparation of patients for thyroid surgery. The sections on less common causes of thyrotoxicosis have been expanded.

CONCLUSIONS

One hundred twenty-four evidence-based recommendations were developed to aid in the care of patients with thyrotoxicosis and to share what the task force believes is current, rational, and optimal medical practice.

Antithyroid Arthritis Syndrome: A Case Report and Review of the Literature

We herein report the case of a 38-year-old Japanese woman with antithyroid arthritis syndrome who experienced severe migratory polyarthritis after the initiation of thiamazole therapy. The patient's symptoms promptly disappeared without any sequelae after the withdrawal of the drug. Antithyroid arthritis syndrome is poorly characterized, and the findings from our literature review indicate that this syndrome exhibits serological features that are distinct from those of antithyroid agent-induced vasculitis syndrome. The absence of autoantibodies, especially anti-neutrophil cytoplasmic antibodies, may help characterize and diagnose antithyroid arthritis syndrome. Furthermore, physicians' awareness of this syndrome is essential for its diagnosis in clinical practice.

Propylthiouracil-induced autoimmune disease

Hyperthyroidism is a condition characterized by excessive production of thyroid hormones. Propylthiouracil (PTU) is commonly used as first line drug in the management of hyperthyroidism. This is a case report of 24-year-old female, a known case of hyperthyroidism since 4 years, who came with a history of fever and myalgia since 3 days and dyspnea with coughing out of blood since 1 day. Patient was taking PTU (100 mg per day) since 4 years for hyperthyroidism. Patient was immediately intubated for type-II respiratory failure. Diagnosed to be having PTU-induced autoimmune disease. PTU was stopped and treated with methylprednisolone and cyclophosphamide. Clinical features improved over a period of 8 days and discharged home successfully. Having a high suspicion for the onset of autoimmune disease in hyperthyroidism patients who are on PTU therapy and timely treatment with immunosuppressants and supportive care along with the withdrawal of the drug can make a difference in morbidity and mortality.

Application of the multifactor dimensionality reduction method in evaluation of the roles of multiple genes/enzymes in multidrug-resistant acquisition in Pseudomonas aeruginosa strains

Multidrug-resistant Pseudomonas aeruginosa (MDRPA) infections are major threats to healthcare-associated infection control and the intrinsic molecular mechanisms of MDRPA are also unclear. We examined 348 isolates of P. aeruginosa, including 188 MDRPA and 160 non-MDRPA, obtained from five tertiary-care hospitals in Guangzhou, China. Significant correlations were found between gene/enzyme carriage and increased rates of antimicrobial resistance (P < 0·01). gyrA mutation, OprD loss and metallo-β-lactamase (MBL) presence were identified as crucial molecular risk factors for MDRPA acquisition by a combination of univariate logistic regression and a multifactor dimensionality reduction approach. The MDRPA rate was also elevated with the increase in positive numbers of those three determinants (P < 0·001). Thus, gyrA mutation, OprD loss and MBL presence may serve as predictors for early screening of MDRPA infections in clinical settings.

Epitope analysis of anti-myeloperoxidase antibodies in propylthiouracil-induced antineutrophil cytoplasmic antibody-associated vasculitis

Introduction

Increasing evidence has suggested that linear epitopes of antineutrophil cytoplasmic antibody (ANCA) directed to myeloperoxidase (MPO) might provide clues to the pathogenesis of propylthiouracil (PTU)-induced ANCA-associated vasculitis (AAV). This study mapped epitopes of MPO-ANCA in sera from patients with PTU-induced MPO-ANCA (with or without vasculitis) and primary AAV, aiming to analyze certain epitopes associated with the development of PTU-induced AAV.

Methods

Six recombinant linear fragments, covering the whole amino acid sequence of a single chain of MPO, were produced from Escherichia coli. Sera from 17 patients with PTU-induced AAV, 17 patients with PTU-induced MPO-ANCA but without clinical evidence of vasculitis, and 64 patients with primary AAV were collected at presentation. Of the 17 patients with PTU-induced AAV, 12 also had sera at remission. The epitope specificities were detected by enzyme-linked immunosorbent assay by using the recombinant fragments as solid-phase ligands.

Results

Compared with patients with PTU-induced MPO-ANCA but without clinical vasculitis, sera from PTU-induced AAV patients showed significantly higher reactivity against the H1 fragment of MPO (optical density values: 0.17 (0.10 to 0.35) versus 0.10 (0.04 to 0.21), P = 0.038) and could recognize a significantly higher number of fragments (two (none to four) versus one (none to two), P = 0.026). Compared with sera from primary AAV patients, sera from PTU-induced AAV patients had significantly higher reactivity to the P fragment and the H4 fragment (47.1% versus 14.1% P < 0.001; 41.2% versus 14.1%, P = 0.034, respectively), and could recognize a significantly higher number of fragments (two (none to four) versus one (none to two), P = 0.013]. Among the 12 PTU-induced AAV patients with sequential samples, the number of fragments recognized in remission was significantly less than that in initial onset (two (none to four) versus none (none to 0.75), P < 0.001].

Conclusions

Linear epitopes of MPO molecules might be associated closely with PTU-induced AAV. In particular, the P and H4 fragments may be important epitopes in PTU-induced AAV.

Diagnosis and classification of drug-induced autoimmunity (DIA)

Since sulfadiazine associated lupus-like symptoms were first described in 1945, certain drugs have been reported to interfere with the immune system and induce a series of autoimmune diseases (named drug-induced autoimmunity, DIA), exemplified by systemic lupus erythematosus (SLE). Among the drugs, procainamide and hydralazine are considered to be associated with the highest risk for developing lupus, while quinidine has a moderate risk, and all other drugs have low or very low risk. More recently, drug-induced lupus has been associated with the use of newer biological modulators, such as tumor necrosis factor (TNF)-alpha inhibitors and cytokines. In addition to lupus, other major autoimmune diseases, including vasculitis and arthritis, have also been associated with drugs. Because resolution of symptoms generally occurs after cessation of the offending drugs, early diagnosis is crucial for treatment strategy and improvement of prognosis. Unfortunately, it is difficult to establish standardized criteria for DIA diagnosis. Diagnosis of DIA requires identification of a temporal relationship between drug administration and the onset of symptoms, but the relative risk with respect to dose and duration for each drug has rarely been determined. DIA is affected by multiple genetic and environmental factors, leading to difficulties in establishing a list of global clinical features that are characteristic of most or all DIA patients. Moreover, the distinction between authentic DIA and unmasking of a latent autoimmune disease also poses challenges. In this review, we summarize the highly variable clinical features and laboratory findings of DIA, with an emphasis on the diagnostic criteria.

Propylthiouracil-induced lupus-like or vasculitis syndrome

A 27 year old female with Graves’ disease presented with fever, exertional dyspnea and polyarthralgia. Erythema nodosum had occured three months earlier. The patient declared irregular use of propylthiouracil (PTU) for the last 8 months. Neutropenia and microscopic hematuria developed in the second week of admission. Chest X-ray showed inhomogenous pulmonary opacities, left pleural effusion and cardiomegaly. Computed tomography (CT) revealed multiple subpleural nodules, left pleural effusion, pericardial effusion, enlarged mediastinal and axillary lymph nodes. Bronchoalveolar lavage (BAL) cytology demonstrated hemosiderin laden macrophages. Histopathologic examination of the transbronchial biopsy specimen revealed a nonspecific inflammation. Serum was positive for ANA, P-ANCA, MPO-ANCA, PR3-ANCA and negative for anti-ds-DNA, C-ANCA, C3, C4 and anti-histone antibody. All symptoms resolved in two months after PTU withdrawal and starting steroid treatment. The same clinical manifestations recurred when the patient used PTU erronously one month after discharge.

This is a case of PTU induced-autoimmune disease in whom the accurate distinction between drug-induced-lupus (DIL) and vasculitis was not possible due to the significant overlap of clinical and laboratory findings causing a significant diagnostic challenge for the chest physician.

Propylthiouracil-induced antineutrophil cytoplasmic antibody-associated vasculitis

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) refers to a group of potentially life-threatening autoimmune diseases. A recent development in this field is the recognition that certain drugs can induce AAV. Among these agents, the drug most often implicated in causing disease is the commonly used antithyroid agent propylthiouracil (PTU). This Review provides an update on PTU-induced AAV. Clinical characteristics of PTU-induced AAV are similar to that of primary AAV, but usually have a milder course and better prognosis, provided early cessation of the disease-causing drug. PTU-induced ANCAs usually react to several components of myeloid granules, which is helpful in differentiating PTU-induced AAV from primary AAV. Early cessation of PTU is crucial in the treatment of PTU-induced AAV. The duration of immunosuppressive therapy might be shorter than in primary AAV, depending on the severity of organ damage, and maintenance therapy is not always necessary.

Concomitant drug- and infection-induced antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis with multispecific ANCA

OBJECTIVE

To report the first case of concomitant drug- and infection-induced antineutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV) in a patient treated with propylthiouracil (PTU) and suffering from tuberculosis.

PRESENTATION AND INTERVENTION

A 28-year-old woman with PTU-treated hyperthyroidism presented with fever, purpura, pulmonary cavitations and ANCA to myeloperoxidase, bactericidal/permeability-increasing protein (BPI), proteinase-3 and elastase. Skin histopathology confirmed vasculitis. However, sputum examination revealed Mycobacterium tuberculosis. Remission was achieved after PTU withdrawal and treatment with antituberculosis drugs.

CONCLUSION

Our case confirmed that BPI-ANCA are elevated in active tuberculosis. Multispecific ANCA were helpful for the diagnosis of concomitant PTU- and M. tuberculosis-induced AAV.

Approach to the pediatric patient with Graves' disease: when is definitive therapy warranted?

Pediatric Graves' disease accounts for 10-15% of thyroid disorders in patients less than 18 yr of age. The onset of symptoms may be insidious and subsequently associated with a delay in diagnosis. Decreased concentration and poor school performance are frequent complaints and can be quite frustrating for the patient and family. Severe ophthalmopathy is uncommon. The diagnosis is established by the findings of an increased heart rate and goiter in the setting of a suppressed TSH and elevated T(3) and/or T(4). The majority of pediatric patients are initially placed on antithyroid medications and maintained on these medications for prolonged periods of time in hopes of achieving remission. Unfortunately, for many children and adolescents remission is unattainable, ultimately occurring in only 15-30% of patients. Several recent studies have suggested that the age of the patient, the degree of thyrotoxicosis at diagnosis, the initial response to therapy, and the level of TSH receptor antibodies serve as reasonable predictors of remission and relapse. However, a consensus on the utility of these markers has not been reached. The present clinical case describes an adolescent with Graves' disease and highlights the negative impact that prolonged medical therapy can have on quality of life and school performance; it reviews pertinent data on the diagnosis, comorbidities, and treatment options; and it identifies gaps in knowledge for when definitive therapy should be pursued. The case serves as a reminder that earlier discussion and decision for definitive therapy should be more commonplace in caring for our pediatric patients with Graves' disease.

Drug allergy: an updated practice parameter

Adverse drug reactions (ADRs) result in major health problems in the United States in both the inpatient and outpatient setting. ADRs are broadly categorized into predictable (type A and unpredictable (type B) reactions. Predictable reactions are usually dose dependent, are related to the known pharmacologic actions of the drug, and occur in otherwise healthy individuals, They are estimated to comprise approximately 80% of all ADRs. Unpredictable are generally dose independent, are unrelated to the pharmacologic actions of the drug, and occur only in susceptible individuals. Unpredictable reactions are subdivided into drug intolerance, drug idiosyncrasy, drug allergy, and pseudoallergic reactions. Both type A and B reactions may be influenced by genetic predisposition of the patient

Occult pulmonary hemorrhage as a rare presentation of propylthiouracil-induced vasculitis

Propylthiouracil, a drug commonly used to treat hyperthyroidism, is known to cause antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis as a rare complication. The wide clinical spectrum of propylthiouracil-induced vasculitis ranges from mild forms with rash and/or arthralgia to severe forms with renal or pulmonary involvement, which can be critical and life-threatening if left unrecognized and untreated. Given its rarity and exceedingly variable clinical presentations, diagnosis may be challenging, and delayed diagnosis is not uncommon without a high index of suspicion, as illustrated by this report of a 17-year-old girl with Graves' disease who developed occult pulmonary hemorrhage as an overlooked rare presentation of ANCA-associated vasculitis after administration of propylthiouracil. Associated clinical features included fever, fatigue, palpable purpura, polyarthritis, and nephritis. Positive findings on chest radiography prompted the bronchoalveolar lavage procedure, which led to the identification of pulmonary hemorrhage. Skin biopsy showed leukocytoclastic vasculitis. Serologic test results were positive for perinuclear ANCA, cytoplasmic ANCA, myeloperoxidase-ANCA, proteinase 3-ANCA, and cryoglobulins but negative for antinuclear antibody, anti-double-stranded DNA, rheumatoid factor, and anti-hepatitis C virus antibody. The symptoms resolved after discontinuation of propylthiouracil and a few months of corticosteroids and azathioprine. This report highlights the necessity for physicians to keep alert for the protean manifestations of propylthiouracil-induced vasculitis.

Drug-induced autoimmunity

PURPOSE OF REVIEW

This review aims to draw attention to the increased spectrum of the features of drug-induced autoimmunity (DIA), including both clinical and autoantibody profiles in addition to the potential chronicity of the syndrome.

RECENT FINDINGS

In recent years, not only has the number of medications causing DIA increased but the spectrum of the features has broadened as well. With the use of newer medications, especially biologics, mostly directed towards immune system manipulation, the range of signs and symptoms of DIA as well as the patterns of autoantibody profiles have widened. Rashes and visceral involvement have started to be reported more often, especially with tumor necrosis factor antagonists. In addition, autoantibodies such as antidouble-stranded DNA, which are usually seen with idiopathic systemic lupus erythematosus, are appearing in place of the antihistone antibodies, typically found in drug-induced lupus. Finally, some medications have been implicated in causing the very same entity, which they may be used to treat. It is clear that progress in the field of pharmacogenetics and pharmacogenomics will help further our understanding of these and other adverse effects of medications.

SUMMARY

Even though DIA has been known for many years, the underlying mechanisms remain unclear. However, with recently described new and unexpected features, novel hypotheses have been proposed, thus opening doors to further research in understanding these mechanisms.

Churg-Strauss Syndrome following PTU Treatment

Propylthiouracil (PTU) is a frequently prescribed drug in the treatment of hyperthyroidism. The use of PTU is, however, accompanied by numerous potentially serious side effects including vasculitis. PTU-related vasculitides can present as haematuria, pulmonary haemorrhage, or cutaneous lesion together with aspecific symptoms such as fever, myalgia, arthralgia, and fatigue. Cerebral involvement is seldom observed. We present a 49-year-old female with Graves' disease and asthma, who developed paresis of the proximal extremities, eosinophilia, pulmonary, and cutaneous lesions following treatment with PTU. A cerebral vasculitis consistent with Churg-Strauss syndrome (CSS) was suspected. Although cerebral involvement is seldom observed with PTU treatment, cerebral vasculitis should be considered in patients developing CNS symptoms.

Infection and vasculitis

Vasculitis may be associated with infection, immunization or anti-microbial drugs. Infections are responsible for a number of different types of vasculitis. Conversely, patients with vasculitis may develop infections, which sometimes mimic relapse. The aim of this review is to summarize the various aspects of the inter-relationship between vasculitis and infection, and the physiopathological mechanisms involved, in light of our current knowledge from animal models. Currently, a causal relationship between infection and vasculitis has only been established in a few instances and many mechanisms remain hypothetical. This inter-relationship is further assessed from the point of view of clinical presentation and therapeutic options, based on case reports and prospective observational data.

Drug-induced vasculitis

PURPOSE OF REVIEW

This review aims to draw attention to the features that distinguish drug-induced vasculitis and drug-induced lupus-like disease from those of idiopathic autoimmune syndromes, first and foremost primary vasculitides and systemic lupus erythematosus. Drug-induced vasculitis and drug-induced lupus-like disease are seen in patients treated long term with a drug, and close to 100 drugs representing all pharmacologic classes have been assumed capable of inducing such syndromes. The clinical phenotypes vary from single tissue or organ involvement to severe systemic inflammatory disease dominated by vasculitis and sometimes organ failure.

RECENT FINDINGS

The recent discovery of antineutrophil cytoplasm antibodies in a large serological subset of drug-induced vasculitis/drug-induced lupus-like disease caused by long-term antithyroid drug treatment has opened new avenues for differential diagnostics. Antineutrophil cytoplasm antibodies with specificity to more than one lysosomal antigen, combined with presence of antibodies to histones and beta-2 glycoprotein 1 constitute a unique serological profile for drug-induced vasculitis/drug-induced lupus-like disease.

SUMMARY

Rational use of laboratory marker profiles is likely to aid in distinguishing drug-induced from idiopathic syndromes. Hence, the use of antineutrophil cytoplasm antibodies and other autoantibodies as biomarkers of different phenotypes of drug-induced vasculitis/drug-induced lupus-like disease is the main focus of this review.

Drug-induced arthritic and connective tissue disorders

OBJECTIVES

All pharmacologic agents have the potential for both benefit and toxicity. Among the more interesting and important adverse consequences of drug therapy are a range of joint and connective tissue complaints that may mimic or reproduce primary rheumatologic diseases. In this article, we review the literature on commonly used drugs reported to induce arthritis and/or connective tissue-based diseases. We assess the strength of the reported associations, discuss diagnostic features and treatment implications, and consider possible mechanisms for drug-induced genesis of rheumatic conditions.

METHODS

We reviewed the Medline database from 1987 to 2006 to identify drug-induced arthritic and connective-tissue disease syndromes, utilizing 48 search terms. A qualitative review was performed after the articles were abstracted and the relevant information was organized.

RESULTS

Three hundred fifty-seven articles of possible relevance were identified. Two hundred eleven publications were included in the final analysis (case series and reports, clinical trials, and reviews). Many drugs were identified as mimicking existing rheumatic conditions, including both well-established small molecules (eg, sulfasalazine) and recently introduced biologic agents (eg, antitumor necrosis factor agents). The most commonly reported drug-induced rheumatic conditions were lupus-like syndromes. Arthritis and vasculitis were also often reported.

CONCLUSIONS

Drug-induced rheumatic syndromes are manifold and offer the clinician an opportunity to define an illness that may remit with discontinuation of the offending agent. Early diagnosis and withdrawal of the drug may prevent unnecessary morbidity and disability.

Drug-induced lupus

Drug-induced lupus (DIL) is a rare adverse reaction to a large variety of drugs with features resembling those of idiopathic systemic lupus erythematosus (SLE). It usually develops only after months and, quite commonly, years of treatment with the offending agent, although latencies of days or weeks have been described in some instances. There are some indications that the risk of DIL can increase with higher daily and cumulative doses and with longer duration of therapy. There are no definitive and commonly accepted diagnostic criteria for DIL, but the following guidelines have been proposed: (a) sufficient and continuing exposure to a specific drug, (b) at least one symptom compatible with SLE, (c) no history suggestive of SLE before starting the drug, and (d) resolution of symptoms within weeks (sometimes months) after discontinuation of the putative offending agent. In addition, it is frequently suggested that the presence of ANA is required for the diagnosis of DIL. However, negative ANA test results should not automatically preclude such a diagnosis, particularly if a patient has other autoantibodies associated with SLE/DIL.

Antineutrophil cytoplasmic autoantibody-associated small-vessel vasculitis

PURPOSE OF REVIEW

This review focuses on recent advances in the diagnosis, pathogenesis and treatment of antineutrophil cytoplasmic autoantibody-associated small-vessel vasculitis.

RECENT FINDINGS

Antineutrophil cytoplasmic autoantibodies are closely associated with Wegener's granulomatosis and microscopic polyangiitis. Within the Churg-Strauss syndrome, antineutrophil cytoplasmic autoantibodies, mostly directed towards myeloperoxidase, characterize patients with glomerulonephritis and small-vessel vasculitis. There is increasing evidence that myeloperoxidase-antineutrophil cytoplasmic autoantibodies are directly involved in the pathogenesis of necrotizing vasculitis. This is less clear for proteinase 3-antineutrophil cytoplasmic autoantibodies, markers for Wegener's granulomatosis. With respect to proteinase 3-antineutrophil cytoplasmic autoantibodies, complementary proteinase 3, a peptide translated from the antisense DNA strand of proteinase 3 and homologous to several microbial peptides, may be involved in induction of proteinase 3-antineutrophil cytoplasmic autoantibodies. Currently, various controlled trials have been initiated. Methotrexate has been shown to be effective for induction of remission in locoregional Wegener's granulomatosis. Other trials are underway.

SUMMARY

Apart from its diagnostic potential, antineutrophil cytoplasmic autoantibodies, particularly myeloperoxidase-antineutrophil cytoplasmic autoantibodies, are directly involved in the pathogenesis of the associated vasculitides. New treatment modalities, supposedly more efficacious and less toxic than daily oral cyclophosphamide, are being tested in randomized controlled trials.