Evidence Of Myositis Research Articles

Incomplete Kawasaki disease with muscular weakness and bladder retention: a case report

BackgroundKawasaki disease (KD) is an acute systemic immune vasculitis affecting multiple organs and systems in children, and is prevalent in children under 5 years of age. Muscular weakness is a rare manifestation of KD, and only 11 pediatric patients with KD combined with muscular weakness have been reported, of which evidence of myositis was found in 2/3 of the patients, and 1/3 could not be explained by myositis, the mechanism of which is still unclear. Cases of KD combined with bladder retention are even more rare, and there has been only 1 case report of KD combined with bladder retention in a child with no previous underlying disease.Case presentationWe report a 22-month-old Asian child with incomplete Kawasaki disease (IKD) who initially presented with fever and progressive muscular weakness in the lower extremities, followed by the bladder and bowel retention abnormalities and rapid onset of heart failure, respiratory failure and shock. The child developed coronary artery ectasia (CAA) without the main clinical features of KD such as rash, conjunctival congestion, desquamation of the extremity endings, orofacial changes and enlarged lymph nodes in the neck. Creatine kinase and electromyography were normal. Temperature gradually normalized and muscle strength recovered slightly after intravenous immunoglobulin. The child could be helped to walk after 1 week of aspirin combined with steroid therapy.ConclusionsWe present the case of a 22-month-old child with IKD. The child began with progressive muscular weakness in the extremities, followed by the bladder and bowel retention abnormalities, and rapidly developed heart failure, respiratory failure, and shock. Despite early failure to detect the disease, the child recovered rapidly and had a favorable prognosis. KD comorbidities with muscular weakness as the main manifestation are uncommon. This is the first case report of IKD combined with both muscular weakness and bladder and bowel retention, which may provide clinicians with diagnostic and therapeutic ideas, as well as a basis for future exploration of the mechanisms of KD combined with muscular weakness or bladder and bowel retention abnormalities.

P152 A rare case of necrotising vasculitis presenting with calf swelling in a 15-year-old female

Abstract Background/Aims We present the case of MF, a 15-year-old female who presented to the paediatric clinic with swelling and pain affecting her right calf. She was previously fit and well. Initial imaging was suggestive of localised myositis but a subsequent muscle biopsy was in keeping with necrotising vasculitis. Methods In May 2021, MF presented to a general paediatric clinic with a 6-week history of right lateral calf pain and swelling to the lateral border of the right proximal fibula. She was systemically well. Blood tests and an x-ray were normal. An ultrasound scan of the right calf showed fusiform thickening of the peroneus longus muscle proximally. There was no discrete mass. The appearance was thought to be an inflammatory process such as myositis. An MRI scan was advised. Over the course of the next few weeks, the swelling and pain to the right calf progressed and she was unable to fully weight bear. Repeat blood tests were normal except CRP 11. CK was normal. At the end of June, an MRI scan of the right lower leg showed significant swelling and oedema along the length of the peroneus longus musculature as demonstrated on ultrasound. Florid oedema extended to involve the soleus and to a lesser extent the lateral head of gastrocnemius. There was thickening and oedema through the subcutaneous fat circumferentially compared to the left side (see images). The appearances were thought to be consistent with myositis but an inflammatory malignancy could not be fully excluded and an opinion from the Birmingham team was recommended. The Birmingham MDT advised that malignancy was unlikely but a CT scan was recommended. The CT scan confirmed the MRI findings (see image). Results MF's symptoms progressed rapidly over a short period of time with diffuse swelling of the right lower limb with associated pain and numbness. She also developed purpuric lesions around the ankle (see photos). The CRP increased to 59 and then 123. CK remained normal. Local rheumatology opinion was sought once malignancy had been excluded. The initial impression was of a focal myositis but a muscle biopsy was requested urgently. IV steroids were administered followed by high dose oral prednisolone as a reducing course. The symptoms improved rapidly. The subsequent biopsy showed a florid necrotising vasculitis affecting the small-medium arterial vessels. There was no evidence of myositis (see image). ANCA was negative and CT renal and abdominal angiogram was normal. Nerve conduction studies showed a very severe sensory lesion of the right sural nerve, which explained the persistent numbness. Mycophenolate mofetil was added and clinical improvement is ongoing. Conclusion We present a rare case of localised vasculitis in the right calf. A literature review indicates this is the first case presented in an adolescent. Disclosure S.C. Earl: None. J. Smith: None. A. Ramanan: Grants/research support; Abbvie.

COVID-19 vaccination-associated anti-Jo-1 syndrome.

Post-vaccination inflammatory myositis is a rare but known entity in the literature. We encountered a 46-year-old female patient, who presented with complains of fever, arthralgia, and weakness 1 week after taking the second dose of COVID-19 (Oxford-AstraZeneca) vaccine. On workup the patient had raised inflammatory markers, evidence of myositis on magnetic resonance imaging of thighs, and evidence of interstitial lung disease on high-resolution computed tomography of the chest. The patient was further found to be positive for anti-Jo-1 antibody. The initial treatment was glucocorticosteroids and methotrexate initially. The patient briefly developed pneumocystis pneumonia and recovered. The treatment was switched to mycophenolate mofetil with good response.We presented the first case of anti-Jo-1 syndrome reported following COVID-19 vaccination in the literature. Our aim is to sensitise the clinicians to such rare but occasionally life-threatening complications that may arise in the post-vaccination period.

Anti-SAE autoantibody-positive Japanese patient with juvenile dermatomyositis complicated with interstitial lung disease - a case report

BackgroundClinical phenotypes and outcomes in juvenile dermatomyositis (JDM) have been defined by various myositis-specific autoantibodies (MSAs). One of the recently described MSAs associated with DM is targeted against the small ubiquitin-like modifier 1 activating enzyme (SAE). We report an anti-SAE autoantibody-positive JDM patient complicated with interstitial lung disease (ILD).Case presentationAn 8-year-8-month-old Japanese girl presented with bilateral eyelid edema and facial erythema. At 8 years 4 months, she had dry cough and papules with erythema on the dorsal side of the interphalangeal joints of both hands. Her facial erythema gradually worsened and did not improve with topical steroids. At the first visit to our department at 8 years 8 months of age, she had a typical heliotrope rash and Gottron’s papules, with no fever or weight loss, and a chest computed tomography scan showed ground-glass opacity under visceral pleura. There was no clinical evidence of myositis, muscle weakness, myalgia, or muscle magnetic resonance imaging (MRI) findings. She had mild dry cough, without any signs of respiratory distress. Laboratory tests showed no elevated inflammatory markers. She had a normal serum creatine kinase level with a slightly elevated aldolase level, and serum anti-SAE autoantibody was detected by immunoprecipitation—western blotting. She was diagnosed with juvenile amyopathic DM complicated by ILD and received two courses of methylprednisolone pulse therapy followed by oral corticosteroid and cyclosporin A. We gradually reduced the corticosteroid dose as her skin rash improved after treatment initiation. There was no progression of muscle symptoms, dysphagia, or disease flare during a 24-month follow-up period.ConclusionsWe report a patient with anti-SAE autoantibody-positive JDM complicated by interstitial pneumonia. This patient had no progression of muscle symptoms and dysphagia during a 24-month follow-up period, which differs from previous reports in adult patients with MSAs. There have been no previous reports of pediatric patients with SAE presenting with ILD. However, ILD seen in this case was not rapidly progressive and did not require cytotoxic agents. To prevent overtreatment, appropriate treatment choices are required considering the type of ILD.

Clinicoserological features of antisynthetase syndrome (ASyS)-associated interstitial lung disease presenting to respiratory services: comparison with idiopathic pulmonary fibrosis and ASyS diagnosed in rheumatology services

IntroductionAntisynthetase syndrome (ASyS) is a rare autoimmune connective tissue disease (CTD), associated with autoantibodies targeting tRNA synthetase enzymes, that can present to respiratory (interstitial lung disease (ILD)) or rheumatology (myositis,...

EP28 A case of ANCA vasculitis presenting with Sjögren’s serology

EP28 A case of ANCA vasculitis presenting with Sjögren’s serology

Mizoribine treatment in an elderly diabetic patient with antisynthetase-associated interstitial lung disease.

Objective: Immunosuppressive therapy for interstitial lung disease (ILD) is often necessary, but the standard regimen for antisynthetase-associated ILD has not been established.Patient: An 80-year-old man was hospitalized for severely progressive dyspnea. Bilateral interstitial shadows occurred 1 month before the event. Serological findings showed that he had antisynthetase-associated ILD, as identified by strong positivity for anti-aminoacyl-transfer RNA synthetase (ARS) antibody, despite no evidence of myositis. He was treated transiently with noninvasive positive pressure ventilation and steroid-pulse therapy followed by 60 mg/day of oral prednisolone. However, his diabetes mellitus was aggravated by corticosteroid therapy; thus, a combination of low-dose steroid and mizoribine (MZB), which has a low risk of aggravating glucose intolerance, was used.Results: The patient’s clinical symptoms and daily life activities have been well persevered as an outpatient and well maintained with 200 mg of MZB and 10 mg of prednisolone for several months without obvious clinical recurrence and without any remarkable steroid- and MZB-related side effects.Conclusion: The use of MZB appeared to suppress the pathophysiology of anti-ARS antibody-associated ILD.

27. A new presentation of interstitial lung disease

27. A new presentation of interstitial lung disease

14. Digital ischemia and interstitial lung disease in antisynthetase syndrome with PL-12 antibody

IntroductionAntisynthetase syndrome (ASS) is a rare idiopathic inflammatory myopathy with nearly 89% showing interstitial lung disease (ILD). The hallmark of ASS is the presence of serum autoantibodies directed against aminoacyl-tRNA synthetases that include Jo-1 (most commonly detected), PL-7, PL-12, OJ, EJ, KS, Wa, YRS and Zo. However, in a small subpopulation without evidence of myositis, the diagnosis may be critically delayed, hindering management of this rapidly progressive disease.We report an interesting case of anti-PL-12/anti-SSA 52kD ASS presenting as acute digital ischemia, an association rarely described previously. In cases with ILD, the severity of lung condition generally determines the prognosis.Case descriptionA 77-year-old Caucasian female presented with sudden onset of painful, blue discolouration in her bilateral fingertips two-weeks after mild lower respiratory tract infection and occasional pyrexia. She was a non-smoker, otherwise independent lady who had background history of ischemic heart disease, diverticulosis and hypertension. Her physical examination revealed dusky blue digits and dry ulceration. She had extensive investigations that showed raised CRP (61mg/L), eGFR 39ml/min/1.73m2 , weak positive rheumatoid factor and cold agglutinins, equivocal Lupus anticoagulant, negative ANCA, clear urinalysis, bilateral chronic inflammatory change on chest xray and thrombi of digital arteries on Doppler ultrasound of hands.She was initially treated for infection due to ongoing temperatures and had multiple scans with no definite source. An inflammatory aetiology was then thought likely due to lack of response to antibiotics and steroid therapy was commenced with settling of fevers and inflammatory markers. Autoimmune screens initially were negative but became more prominent over time with a positive Ro antibody and ultimately a positive Anti PL12 antibody, keeping with anti-synthetase syndrome.She subsequently developed florid interstitial lung disease, further ischemia and ultimately necrosis of her fingertips. Due to the onset of lung disease she was treated with IV steroids, Cyclophosphamide and Prostaglandins with some initial benefit. She received 3 cycles of cyclophosphamide and managed to come off supplemental oxygen. However, she had issues with recurrent chest infections due to immunosuppressive therapy which resulted in delays in her cyclophosphamide pulses and need for antibiotics. She later developed clostridium-difficile gastroenteritis and subsequent ileus of her bowel which was managed conservatively and found it difficult to overcome. As time went on, the progress that she had made with her hands started to deteriorate again. There were also further issues with intestinal obstruction, and sadly ultimately passed away with aspiration pneumonia.DiscussionASS is recognized as a rare autoimmune inflammatory myopathy of unknown etiology, 2–3 times more prevalent in women than in men. The clinical manifestations include myositis, polyarthritis, ILD, mechanic’s hands, and Raynaud phenomenon. The hallmark of ASS is the presence of serum autoantibodies directed against aminoacyl-tRNA synthetases that include Jo-1, PL-7, PL-12, OJ, EJ, KS, Wa, YRS and Zo. Anti-jo1 is the most commonly detected antibody. These autoantibodies may arise after viral infections, or patients may have a genetic predisposition.Our case was interesting as the autoimmune profile was positive for Anti-Ro/SSA and anti-PL-12. Anti-Ro/SSA and anti-La/SSB are traditionally associated with Sjögren’s disease and Sjögren’s-related ILD, however, anti-Ro/SSA has been independently associated with ASS and more severe and fibrotic ILD. It has been described that patients with anti-PL-12-ASS are most often clinically diagnosed with amyopathic dermatomyositis or ILD alone and there is higher prevalence and increased severity of ILD than PM/DM. Moreover, the prevalence of muscle symptoms (weakness and myalgia) is significantly lower in patients with anti-PL7/PL12 as compared to those with anti-Jo1 and less associated with malignancy as compared to DM. Interestingly, anti-PL-12 is also associated with higher rates of Raynaud phenomenon.Our case also reports that not all patients with antisynthetase antibodies or even those classified as ASS have all manifestations of this syndrome. Diagnostic criteria refers to presence of antisynthetase antibody plus two major criteria or one major criterion and two minor criteria (Solomon et all. 2011) or one or more of clinical features (Connors et all.2010). When the lungs are affected, the severity and extent of lung damage generally determines the prognosis because respiratory failure is the leading cause of death. Clinical presentation guides towards therapeutic management that mostly includes corticosteroids, immunosuppressive medications, and/or physical therapyKey learning pointsDigital ischemia could be a rare presentation of ASS. Clinical features of antisynthetase syndrome (ASS) include interstitial lung disease, ‘mechanic’ hands, myositis, polyarthritis and Raynaud’s phenomenon. Extensive myositis specific antibody testing is strongly recommended even if screening autoimmune serologies are unrevealing. Anti- PL-12 ASS has significantly lower prevalence of muscle symptoms (weakness and myalgia) and more association with Raynaud’s phenomenon as compared to those with anti-Jo1. It is imperative to recognize lesser-known manifestations of ASS in the absence of clinical myositis as delay in diagnosis and treatment worsens the prognosis.Conflicts of interestThe authors have declared no conflicts of interest.

Juvenile Onset Clinically Amyopathic Dermatomyositis Presenting as Calcinosis Cutis

Dermatomyositis (DM) is an autoimmune inflammatory disorder characterized by involvement of muscles and skin. Classical dermatomyositis (CDM) patients display the hallmark cutaneous manifestations of dermatomyositis (DM), proximal muscle weakness, and laboratory evidence of myositis. Rarely, DM presents with cutaneous features of the disease without muscle involvement for a period of more than six months. Such cases are classified into a category of clinically amyopathic dermatomyositis (CADM) which includes amyopathic DM and hypomyopathic DM. We present a case of a 14-year-old child who presented with calcinosis cutis and cutaneous findings suggestive of the disease without muscle involvement. The child was diagnosed as a case of juvenile onset CADM.J Enam Med Col 2018; 8(2): 101-104

Diffuse microvascular C5b-9 deposition is a common feature in muscle and nerve biopsies from diabetic patients

Terminal complement complex deposition in endomysial capillaries detected by a C5b-9 immunostain is considered a diagnostic feature for dermatomyositis. However, we found widespread microvascular C5b-9 reactivity in a substantial subset of muscle biopsies with denervation changes, and in nerve biopsies of peripheral neuropathies, particularly in patients with diabetes. It is unclear whether the presence of C5b-9 deposition signifies active immune-mediated vascular injury that requires immune suppression therapy. We retrospectively identified 63 nerve biopsies in patients with a documented history of diabetes, 26 of which had concomitant muscle biopsies, as well as 54 control nerve biopsies in patients without a documented diabetes history, 18 of which had concomitant muscle biopsies. C5b-9 immunostain was performed on all cases. 87% of the nerve biopsies and 92% of the muscle biopsies from diabetic patients showed microvascular C5b-9 reactivity, compared to 34% and 50% in non-diabetic patients. The differences were statistically significant (p < 0.0001 for nerve and p = 0.002 for muscle). The C5b-9 reactivity was generally proportional to the extent of microvascular sclerosis in diabetic patients, but unrelated to inflammation or vasculitis. C5b-9 deposition in micro-vasculature in both muscle and nerve is therefore a common feature in patients with diabetic neuropathies and may have diagnostic utility. Precaution needs to be taken before using muscle capillary C5b-9 reactivity as evidence of myositis.

Clinical Profile of Novel H1N1 Influenza in Children at a Tertiary Care Centre: Pune

Background: With worldwide presence, Novel influenza virus (H1N1) carries great potential for causing a pandemic,there are limited studies about clinical profile of H1N1 in paediatric age group in India hence the present study was undertaken at Aditya Birla Memorial Hospital in Pune. Methods: This was a prospective observational study, conducted during the time period from 01/03/2015 to 31/05/2016. Patients with influenza-like illness (Category B and C) aged 1 month to 16 yrs were included. Epidemiological, clinical and laboratory data was collected. For each patient one nasal and one throat swab was collected and sent to laboratory for RT-PCR (Real Time Polymerase Chain Reaction). All cases were treated with oral Oseltamivir according to MOHFW (Ministry Of Health and Family Welfare) guidelines. Data was analyzed for patients with positive RT-PCR. Results: Total 148 patients were enrolled in the study. H1N1 Influenza infection was confirmed on RT-PCR in 24.32% (n=36) patients. Majority of H1N1 infected patients (66.66%; n=24) were between 1-6 yrs and 22.22% were more than 6 yrs with mean age of 5.2 yrs. Male: Female ratio was 1.57:1. History of positive contact was obtained in 22.22% (n=8). In spite of earlier vaccination for H1N1 22.22% (n=8) suffered from infection.Common symptoms were fever (100%), cough (88.88%), rhinorrhoea (83.33%), vomitings (22.22%) and loose stools (22.22%). Normal chest X-ray was found in 38.88% of them, patchy consolidation in 33.33%, prominent broncho-vascular markings in 22.22% and pleural effusion in 5.55%. Fever lasted for more than 7 days in 33.33%. Secondary bacterial infection was found in 16.66% and 5.55% had evidence of myositis. 5.55% had evidence of encephalitis. Mechanical ventilation was required in 11% during the course of treatment. Mean duration of hospitalization was 4.1 days. One deaths occurred.

Bridge to diagnosis: The use of extracorporeal membrane oxygenation in a child with interstitial lung disease secondary to clinically amyopathic dermatomyositis

Abstract Clinically amyopathic dermatomyositis (CADM), a subtype of dermatomyositis (DM), is characterized as having the classic cutaneous manifestations of DM but with little or no evidence of myositis. The presence of anti-melanoma differentiation associated gene 5 (anti-MDA-5) autoantibodies, in the setting of CADM, is associated with rapidly progressive interstitial lung disease (RPILD). The use of extracorporeal membrane oxygenation (ECMO) in patients with RPILD has been well described in adults, but not in children. Herein we present a 14-year old patient with interstitial lung disease, initially of unknown etiology, whom we supported with ECMO in the acute phase of her illness for nearly two months during which the diagnosis of anti-MDA-5 dermatomyositis was established.

Clinical and Serological Features of Patients with anti-Jo-1

Objective: To elucidate the clinical and serological features of patients with anti-Jo-1 antibodies. Methods: Between 2007 and 2010, patients with positive anti-Jo-1 antibodies were enrolled in a study conducted at National Taiwan University Hospital. Their clinical and serological features were obtained by reviewing medical records, laboratory databases, and image studies. Results: On the basis of the information review, 45 patients with positive anti-Jo-1 antibodies were identified. Seven patients had polymyositis, 2 patients had dermatomyositis, and 2 patients had interstitial lung disease (ILD) without evidence of myositis. The most frequent symptoms were joint manifestation and sicca syndrome: 90.9% patients in the myositis/ILD group and 32.3% patients in the non-myositis/ILD group showed joint manifestation, and 45.5% patients in the myositis/ILD group and 44.1% patients in the non-myositis/ILD group had sicca syndrome. Raynaud's phenomenon, fever, and skin rash occurred in 27.2%, 45.5%, and 36.4% of the patients in the myositis/ILD group, and in 20.5%, 17.6%, and 17.6% of the patients in the non-myositis/ILD group. Serological profiles of the patients showed positive antinuclear antibody in 22 patients and positive rheumatoid factor in 10 patients. The initial presentations of 34 patients without myositis or ILD were recorded; the presentations were very heterogeneous. Conclusion: Anti-Jo-1 antibody is one of the most important autoantibodies in idiopathic inflammatory myopathies. In our study, patients with anti-Jo-1 antibodies had highly variable clinical presentations. Our findings also revealed that negative or low titers in antinuclear antibody testing could not exclude the presence of anti-Jo-1 antibody.

Clinically amyopathic dermatomyositis

Clinically amyopathic dermatomyositis (CADM) is a unique subset of dermatomyositis, with typical skin manifestations of dermatomyositis but little or no evidence of myositis. This review focuses on updates on epidemiology, clinical manifestations, and autoantibody profiles in patients with CADM. A population-based survey of dermatomyositis conducted in the United States revealed that overall age-adjusted and sex-adjusted incidence of CADM was 2.08 per 1 million persons. CADM consisted of approximately 20% of dermatomyositis. In general, late-onset myositis was infrequent. There was no apparent difference in frequency of internal malignancy or interstitial lung disease between CADM and classic dermatomyositis. However, anecdotal and retrospective case reports from eastern Asia showed a relatively high incidence of rapidly progressive interstitial lung disease, which is often fatal, in patients with adult-onset and juvenile-onset CADM. Finally, RNA helicase encoded by melanoma differentiation-associated gene 5 was identified as an autoantigen recognized by anti-CADM-140 antibody, which is associated with CADM and rapidly progressive interstitial lung disease. CADM is a distinct clinical entity with unique clinical features and autoantibody profiles different from classic dermatomyositis.

Radiation-recall myositis presenting as low-back pain (2010: 4b)

We report on a patient with a history of Ewing sarcoma who underwent surgery and subsequent adjuvant chemotherapy and radiotherapy. He developed low-back pain 6 months after the end of the radiotherapy and during consolidation chemotherapy. Magnetic resonance imaging showed evidence of myositis corresponding to the 'radiation-recall phenomenon', an inflammatory reaction of irradiated tissue.

Clopidogrel-Precipitated Rhabdomyolysis in a Stable Heart Transplant Patient

To report the case of an orthotopic heart transplant recipient who developed rhabdomyolysis precipitated by the addition of clopidogrel to the existing regimen of cyclosporine and atorvastatin, which had been tolerated for more than 3 years without adverse effects or laboratory evidence of myositis. Fourteen years after cardiac transplantation, a 58-year-old woman began a planned 4 week course of clopidogrel 75 mg/day following coronary angioplasty and placement of a stent in the left circumflex coronary artery. Almost 4 weeks later, she presented with severe muscle pain and weakness and laboratory evidence of rhabdomyolysis, with marked elevations of plasma creatine kinase (96,000 U/L) and urine myoglobin (332,872 microg/L) as well as early acute renal failure (serum creatinine 2.9 mg/dL). Symptoms and laboratory abnormalities resolved with cessation of cyclosporine, atorvastatin, and clopidogrel. Clopidogrel was not restarted, while atorvastatin and cyclosporine were; the patient had no recurrence of symptoms up to 15 months later. Both atorvastatin and cyclosporine, as well as clopidogrel's active thiol derivative, are metabolized by the cytochrome P450 3A4 isoenzyme. Cyclosporine is also a moderate inhibitor of this isoenzyme. We postulate that competition between atorvastatin and clopidogrel for CYP3A4 receptors, already partially inhibited by cyclosporine, led to increased atorvastatin concentrations, resulting in the acute onset of rhabdomyolysis. This theory is further supported by the patient's continued ability to tolerate the combination of atorvastatin and cyclosporine, without clopidogrel, on rechallenge. Use of the Naranjo probability scale revealed that rhabdomyolysis was probably precipitated by the addition of clopidogrel to the stable baseline regimen of cyclosporine and atorvastatin. Practitioners must be conscious of the potential for adverse effects when prescribing clopidogrel to heart transplant patients who are concomitantly receiving cyclosporine and a statin. If concomitant administration is required, careful clinical and laboratory monitoring of the patient is necessary.

Interstitial lung disease in a patient with antisynthetase syndrome and no myositis

Interstitial lung disease in patients with antisynthetase syndrome and no evidence of myositis is rare and may precede other disease manifestations. We report a patient who initially presented with symptoms primarily related to lung involvement. The diagnosis of the antisynthetase syndrome without myositis was made many months later when he developed a characteristic hand rash (mechanic's hands), which was confirmed by positive antibodies to Jo-1. With treatment, both the hand rash and the interstitial lung disease improved. Antisynthetase syndrome should be considered in patients presenting with interstitial lung disease with no evidence of myositis. Appropriate laboratory testing with measurement of specific autoantibodies may help in the early diagnosis and treatment of the syndrome.

The Shrinking Lungs Syndrome in Systemic Lupus Erythematosus

The Shrinking Lungs Syndrome in Systemic Lupus Erythematosus

Anti-KS: Identification of Autoantibodies to Asparaginyl-Transfer RNA Synthetase Associated with Interstitial Lung Disease

Autoantibodies to five of the aminoacyl-transfer RNA (tRNA) synthetases have been described, and each is associated with a syndrome of inflammatory myopathy with interstitial lung disease (ILD) and arthritis. Serum KS, from a patient with ILD and inflammatory arthritis without evidence of myositis, immunoprecipitated a tRNA that was distinct from that precipitated by any described anti-synthetase or other reported tRNA-related Abs, along with a protein of 65 kDa. KS serum and IgG fraction each showed significant (88%) inhibition of asparaginyl-tRNA synthetase (AsnRS) activity, but not of any of the other 19 aminoacyl-tRNA synthetase activities. Among 884 patients with connective tissue diseases tested, only two other sera were found to immunoprecipitate tRNAs and proteins of identical gel mobility. These two and KS showed identical immunodiffusion lines using HeLa cell extract. The new sera significantly inhibited AsnRS without significant effects on other synthetases tested. Both patients had ILD but neither had evidence of myositis. These data strongly suggest that these three sera have autoantibodies to AsnRS, representing a sixth anti-synthetase. Anti-KS was more closely associated with ILD than with myositis. Further study of this Abs might prove useful in dissecting the stimuli responsible for the genesis of anti-synthetase autoantibodies.