Antisynthetase Syndrome

Last updated: February 8, 2026Reviewed date: February 8, 2026Reading time: 14 min read
Patient Tools

Read, save, and share this guide

Use these quick tools to make this medical article easier to read, print, save, or share with a family member.

Patient Mode

Understand this article easily

Switch between simple English and easy Bangla patient notes. This is for education and does not replace a doctor consultation.

Antisynthetase syndrome is a rare, chronic, autoimmune disorder characterized by Interstitial Lung Disease (ILD), inflammatory myositis, fever, Raynaud’s phenomenon, mechanic’s hand, and inflammatory polyarthritis in the setting of antibodies against amino acyl-transfer RNA synthetases, with anti-Jo-1 antibody being the most common and affect multiple systems...

For severe symptoms, danger signs, pregnancy, child illness, or sudden worsening, seek urgent medical care.

বাংলা রোগী নোট এখনো যোগ করা হয়নি। পোস্ট এডিটরে “RX Bangla Patient Mode” বক্স থেকে সহজ বাংলা সারাংশ যোগ করুন।

এই তথ্য শিক্ষা ও সচেতনতার জন্য। এটি ডাক্তারি পরীক্ষা, রোগ নির্ণয় বা প্রেসক্রিপশনের বিকল্প নয়।

Article Summary

Antisynthetase syndrome is a rare, chronic, autoimmune disorder characterized by Interstitial Lung Disease (ILD), inflammatory myositis, fever, Raynaud’s phenomenon, mechanic’s hand, and inflammatory polyarthritis in the setting of antibodies against amino acyl-transfer RNA synthetases, with anti-Jo-1 antibody being the most common and affect multiple systems of the body. The disorder is immune-mediated, which means there is inflammation resulting from abnormal functioning of the immune system...

Key Takeaways

  • This article explains Causes in simple medical language.
  • This article explains Symptoms in simple medical language.
  • This article explains Diagnosis in simple medical language.
  • This article explains Treatment in simple medical language.
Educational health guideWritten for patient understanding and clinical awareness.
Reviewed content workflowUse writer and reviewer profiles for stronger trust.
Emergency safety firstUrgent warning signs are highlighted below.

Seek urgent medical care if you notice

These warning signs are general safety guidance. Local emergency numbers and clinical judgment should always come first.

  • Severe symptoms, breathing difficulty, fainting, confusion, or rapidly worsening illness.
  • New weakness, severe pain, high fever, or symptoms after a serious injury.
  • Any symptom that feels urgent, unusual, or unsafe for the patient.
1

Emergency now

Use emergency care for severe, sudden, rapidly worsening, or life-threatening symptoms.

2

See a doctor

Book a professional medical evaluation if symptoms persist, worsen, recur often, affect daily activities, or occur in a high-risk patient.

3

Learn safely

Use this article to understand possible causes, tests, treatment options, prevention, and questions to ask your clinician.

Before reading

RX Patient Tools

Use these quick guides before reading the article, or return to them when you need help preparing questions for a doctor.

Start here Choose the right pathway for symptoms, reports, medicines, or urgent warning signs. Disease article roadmap Read this topic step by step: meaning, symptoms, warning signs, diagnosis, treatment, prevention, and follow-up. Treatment planner Prepare questions about treatment choices, benefits, risks, side effects, and follow-up. Family & caregiver guide Organize symptoms, reports, medicines, questions, and follow-up safely. Nutrition & diet guide Prepare food, hydration, supplement, and medicine-timing questions safely. Prevention guide Organize risk factors, protective habits, screening, and warning signs. Recovery guide Prepare a safe plan for activity, rehabilitation, warning signs, and follow-up.
Definition

Antisynthetase syndrome is a rare, chronic, autoimmune disorder characterized by Interstitial Lung Disease (ILD), inflammatory myositis, fever, Raynaud’s phenomenon, mechanic’s hand, and inflammatory polyarthritis in the setting of antibodies against amino acyl-transfer RNA synthetases, with anti-Jo-1 antibody being the most common and affect multiple systems of the body. The disorder is immune-mediated, which means there is infection, or irritation, often causing pain, swelling, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।" data-rx-term="inflammation" data-rx-definition="Inflammation is the body’s response to injury, infection, or irritation, often causing pain, swelling, heat, or redness. সহজ বাংলা: শরীরের প্রদাহ; ব্যথা, ফোলা বা লালভাব হতে পারে।">inflammation resulting from abnormal functioning of the immune system and the presence of specific autoantibodies that target a specific protein in the body. The symptoms and severity of the disorder can vary greatly among affected individuals. Common symptoms include inflammation of the muscles (myositis), inflammation of several joints (polyarthritis), interstitial lung disease, thickening and cracking of the skin of the hands, and a condition called the Raynaud phenomenon, in which the fingers or toes are numb or have a prickly sensation in response to cold. Affected individuals also have nonspecific symptoms like fatigue, unexplained fevers, and unintended weight loss. The exact, underlying cause is not fully understood. Antisynthetase syndrome sometimes occurs along with other conditions such as uncommon inflammatory muscle diseases like dermatomyositis or polymyositis.

It was described as a triad of polymyositis,diffuse interstitial lung disease and serum autoantibodies to aminoacyl transfer RNA synthetase (anti-ARS). The pathogenesis of antisynthetase syndrome involves autoantibodies to eight of the aminoacyl–transfer RNA synthetases. In ASS, 68-87% of the anti-ARS consists of anti-jo-1 antibody. Seven other anti-ARS identified are rarely seen. Anti SSA autoantibodies and anti-Ro 52 are frequently seen in anti–ARS positive patients []. ASS is characterized by varying degrees of interstitial lung disease, myositis, arthropathy, fever, Raynaud’s phenomenon and mechanic’s hands []. Key features for the diagnosis of ASS include the presence of an Anti-ARS antibody, accompanied by myositis, ILD or both [].

Causes

The exact cause of the antisynthetase syndrome is not fully understood. Affected individuals have autoantibodies. Antibodies are part of the immune system; they are specialized proteins that target foreign or invading organisms. Autoantibodies are ones that mistakenly attack healthy tissue. In antisynthetase syndrome, affected individuals have autoantibodies that target certain enzymes in the body called aminoacyl-tRNA synthetases. Enzymes are specialized proteins that help to bring about specific biochemical reactions in the body and aminoacyl-tRNA synthetases help to regulate the production of other proteins and are important for the overall health and function of the body. Research does not know why these autoantibodies targets aminoacyl-tRNA synthetase. Not every person who develops these autoantibodies will go on to develop symptoms of the antisynthetase syndrome.

The exact role these autoantibodies play in the development of antisynthetase syndrome is not fully understood. The autoantibodies that have been identified in this disorder include anti-Jo1, anti-EJ, anti-OJ, anti-PL7, anti-PL12, anti-SC, anti-KS, anti-JS, anti-HA, anti-YRS, anti-tryptophanyl, and anti-Zo. Anti-Jo1 is the most common autoantibody in individuals with the antisynthetase syndrome.

Some autoantibodies are more likely to be associated with specific symptoms. Muscle disease occurs more often with anti-Jo1 or anti-PL7. Interstitial lung disease occurs more often with anti-PL7, anti-PL12, anti-KS, and anti-OJ autoantibodies. Some individuals with anti-OJ autoantibodies have developed severe muscle weakness.

These autoantibodies are believed to be produced after a ‘triggering’ event such as a viral infection or exposure to certain drugs. When the immune system responds to these triggering events, something goes wrong, and these autoantibodies are created that then damage healthy tissue.

Some affected individuals may have a genetic predisposition to developing the antisynthetase syndrome. A genetic predisposition means that a person may carry a gene or genes for a particular condition, but the condition will not develop unless other factors help to trigger the disease. Most likely, the antisynthetase syndrome is a multifactorial disease, in which multiple factors including immune, genetic and environmental ones are necessary for the development of the disorder.

Diagnosis

A diagnosis of the antisynthetase syndrome is based upon the identification of characteristic symptoms, a detailed patient history, a thorough clinical evaluation, and tests that confirm the presence of autoantibodies against the enzyme, aminoacyl-tRNA synthetase.

These may include the following depending on the clinical context:

  • Muscle enzymes eg creatinine kinase (CK) and aldolase: these are often elevated
  • Muscle antibodies
  • Electromyography (EMG)
  • Magnetic resonance imaging (MRI) of affected muscles
  • Muscle biopsy
  • Lung function tests
  • High resolution computed tomography scan (CT) of the chest
  • Evaluation of swallowing difficulties and aspiration risk
  • Lung biopsy

Clinical Testing and Workup

Blood tests can reveal the presence of autoantibodies against the enzyme, aminoacyl-tRNA synthetase. Every person who has one of these autoantibodies does not, necessarily, develop the antisynthetase syndrome. There are published criteria that have been proposed to help with diagnosis. However, these criteria are not universally accepted, and some physicians feel people may have antisynthetase syndrome even if they do not meet the requirements for diagnosis under these guidelines. Based on the guidelines, affected individuals must also have two major criteria or one major criterion, or two minor criteria of the disorder. The two major criteria are interstitial lung disease and muscle disease. Minor criteria are arthritis, the Raynaud phenomenon, or the thickening and cracking of the skin of the hands (mechanic’s hands).

Blood tests can also reveal elevated levels of creatine kinase or aldolase, which are muscle enzymes. When these muscle enzymes are elevated, it is a sign of muscle damage. This is not specific to the antisynthetase syndrome and is a sign of many different types of muscle disease.

A specialized imaging technique called high-resolution computerized tomography (CT) scanning may be used to detect and evaluate lung disease. During CT scanning, a computer and x-rays are used to create a film showing cross-sectional images of certain tissue structures. High-resolution CT scanning involves specific techniques that enhance or improve the resolution of the images. Pulmonary function tests may be administered to determine how effectively or ineffectively the lungs are working.

Specialized testing that records electrical activity in skeletal muscle at rest and during muscle contraction (electromyography [EMG]) may be performed to determine the health and effectiveness of the muscles.

Treatment

The treatment of antisynthetase syndrome is directed toward the specific symptoms that are apparent in each individual. Treatment may require the coordinated efforts of a team of specialists. General internists, specialists in the diagnosis and treatment of lung diseases (pulmonologists), specialists in the diagnosis and treatment of skeletal and muscle diseases (orthopedists), specialists in the diagnosis and treatment of immunological diseases (immunologists), and other healthcare professionals may need to systematically and comprehensively plan an affected child’s treatment. Psychosocial support for the entire family is essential as well.

There are no standardized treatment protocols or guidelines for affected individuals. Due to the rarity of the disease, there are no treatment trials that have been tested on a large group of patients. Various treatments have been reported in the medical literature as part of single case reports or small series of patients. Treatment trials would be very helpful to determine the long-term safety and effectiveness of specific medications and treatments for individuals with the antisynthetase syndrome.

Glucocorticosteroids are the mainstay of treatment for antisynthetase syndrome and are often required for several months or years. Prednisone is initially given at high doses (1 mg/kg/day) for 4–6 weeks to achieve disease control, then tapered slowly over 9–12 months to the lowest effective dose to maintain remission. In more severe cases, pulsed intravenous (IV) methylprednisolone for 3–5 days may be necessary.

Prednisone in the dose of 1mg/kg/day remains the drug of choice for the treatment of this disorder. High dose of steroid is used in the initial phase. Remission is achieved in 25-68% of cases when high dose of corticosteroids are given as part of initial therapy []. Studies have found a better response to steroid therapy in patients with Non-Specific Interstitial Pneumonia (NSIP) and Cryptogenic Organizing Pneumonia (COP) when compared to those with Usual interstitial pneumonia (UIP) []. Monthly IV pulse therapy with cyclophosphamide has shown to be effective when ILD is prominent. Steroid sparing agents azathioprine, methotrexate and cyclosporine have been used with low to moderate success []. Mycophenolate mofetil has been used in anti-jo-1 positive patients with refractory ILD with improvement of ILD. In some series Rituximab has been used with moderate success in patients with worsening of the ILD despite aggressive conventional treatment. However, prospective studies are needed to assess the safety issues of Rituximab []. The dermatologic manifestations are treated with hydroxychloroquine. ILD is the major determinant of morbidity and mortality in Antisynthetase syndrome.

Anti-TNF inhibitors, such as etanercept (Enbrel) and adalimumab (Humira), are medications typically used for rheumatoid arthritis. If arthritis symptoms are predominant in a patient with antisynthetase syndrome, these medications may be preferred. They should be used with caution, however, as these biologic drugs are sometimes associated with the development of myositis.

Intravenous immunoglobulin (IVIG), a blood product containing the pooled immunoglobulin G antibodies from donors, is used in the treatment of many immune deficiency and autoimmune disorders, though its exact mechanism of action is unknown. In a randomized, placebo controlled trial of IVIG treatment in 15 patients with dermatomyositis, patients randomized to receive IVIG had significant improvement in muscle strength and symptoms (). A recent case report suggested

Affected individuals may be treated with drugs that help to reduce inflammation called corticosteroids or drugs that suppress the activity of the immune system (immunosuppressive drugs). The effectiveness of these treatments and the amount of time an individual must remain on these medications will vary.

A drug called hydroxychloroquine has been used to treat skin symptoms. Physical therapy is recommended to help to treat muscle disease by increasing muscle strength and reducing muscle wasting.

Investigational Therapies

Some of the drugs that have been used to treat affected individuals include azathioprine, methotrexate, cyclophosphamide, cyclosporine, tacrolimus, and mycophenolate mofetil, or rituximab. More research is necessary to determine the long-term safety and effectiveness of these medications for the treatment of the antisynthetase syndrome.

Therapies for Anti-synthetase Syndrome-ILD

Drug Suggested Starting Dose Clinical Use Monitoring Adverse effects*
Corticosteroids 1 mg/kg/day First-line therapy Glucose, weight, blood pressure Hypertension, weight gain, hyperglycemia
Azathioprine 1 mg/kg/day Most common second-line agent CBC, renal/liver function Leukopenia, hepatic injury, pancreatitis
Mycophenolate mofetil 500 mg twice daily Second-line agent in addition to corticosteroids CBC Diarrhea, cytopenias
Tacrolimus 1 mg twice daily Add-on therapy Renal function, blood pressure, electrolytes, CBC, drug level Renal failure, hypertension, hyperglycemia
Rituximab ** Rescue therapy, added to standard immunosuppression CBC Infection, neutropenia, infusion reaction
Cyclophosphamide 1–2 mg/kg/day by mouth or 500–1000 mg IV every 4 weeks** Rescue therapy (e.g. ARDS) CBC, urinalysis, renal function Malignancy, cytopenias, hemorrhagic cystitis, sterility
IVIG ** Add-on therapy Immunoglobulin G levels Infusion reaction, infection from donor

References

Doctor visit helper

Prepare before seeing a doctor

A simple rural-patient checklist to help you explain symptoms clearly, ask better questions, and avoid unsafe self-treatment.

Safety note: This is not a prescription or diagnosis. For severe symptoms, pregnancy danger signs, children with serious illness, chest pain, breathing difficulty, stroke-like weakness, or major injury, seek urgent care.

Which doctor may help?

Start with a registered doctor or the nearest qualified health center.

What to tell the doctor

  • Write when the problem started and how it changed.
  • Bring old prescriptions, investigation reports, and current medicines.
  • Write allergies, pregnancy status, diabetes, kidney/liver disease, and major past illnesses.
  • Bring one family member if the patient is weak, elderly, confused, or a child.

Questions to ask

  • What is the most likely cause of my symptoms?
  • Which danger signs mean I should go to hospital quickly?
  • Which tests are necessary now, and which can wait?
  • How should I take medicines safely and what side effects should I watch for?
  • When should I come for follow-up?

Tests to discuss

  • Vital signs: temperature, pulse, blood pressure, oxygen saturation
  • Basic physical examination by a clinician
  • CBC, urine test, blood sugar, or imaging only when clinically needed

Avoid these mistakes

  • Do not use antibiotics, steroid tablets/injections, or strong painkillers without proper medical advice.
  • Do not hide pregnancy, kidney disease, ulcer, allergy, or blood thinner use.
  • Do not delay emergency care when danger signs are present.

Medicine safety and first-aid guide

This section is for patient education only. It does not replace a doctor, pharmacist, or emergency care.

Safe first steps

  • Avoid heavy lifting, sudden bending, and prolonged bed rest.
  • Use comfortable posture and gentle movement as tolerated.
  • Discuss physiotherapy, X-ray, or MRI only when clinically needed.

OTC medicine safety

  • For mild back pain, pain-relief medicine may be discussed with a doctor or pharmacist.
  • Avoid repeated painkiller use if you have kidney disease, stomach ulcer, uncontrolled blood pressure, or are taking blood thinners.

Avoid these mistakes

  • Do not start antibiotics without a proper medical decision.
  • Do not use steroid tablets or injections casually for quick relief.
  • Do not delay emergency care because of home remedies.

Get urgent help if

  • Back pain with leg weakness, numbness around private area, loss of urine/stool control, fever, cancer history, or major injury needs urgent care.
Medicine names, dose, and timing must be decided by a qualified clinician or pharmacist after checking age, pregnancy, allergy, other diseases, and current medicines.

For rural patients and family caregivers

Patient health record and symptom diary

Write your symptoms, medicines already taken, test results, and questions before visiting a doctor. This note stays on your device unless you print or copy it.

Doctor to discuss: Medicine doctor / pediatrician for children / qualified clinician
Tests to discuss with doctor
  • Temperature chart and hydration assessment
  • CBC with platelet count if fever persists or dengue/other infection is possible
  • Urine test, malaria/dengue tests, chest evaluation, or blood culture only when clinically indicated
Questions to ask
  • What is the most likely cause of my symptoms?
  • Which warning signs mean I should go to emergency care?
  • Which tests are really needed now?
  • Which medicines are safe for my age, pregnancy status, allergy, kidney/liver/stomach condition, and current medicines?
  • Do I need antibiotics, or is this more likely viral?

Emergency warning signs such as chest pain, severe breathing difficulty, sudden weakness, confusion, severe dehydration, major injury, or loss of bladder/bowel control need urgent medical care. Do not wait for online information.

Safe pathway to proper treatment

Care roadmap for: Antisynthetase Syndrome

Use this simple roadmap to understand the next safe steps. It is educational and does not replace examination by a doctor.

Go to emergency care if you notice:
  • Severe or rapidly worsening symptoms
  • Breathing difficulty, chest pain, fainting, confusion, severe weakness, major injury, or severe dehydration
Doctor / service to discuss: Qualified healthcare provider; specialist depends on symptoms and examination.
  1. Step 1

    Check danger signs first

    If danger signs are present, seek emergency care and do not wait for online information.

  2. Step 2

    Record the symptom story

    Write when symptoms started, severity, medicines already taken, allergies, pregnancy status, and test results.

  3. Step 3

    Visit a qualified clinician

    A doctor, nurse, or qualified healthcare provider can examine you and decide which tests or treatment are needed.

  4. Step 4

    Do only useful tests

    Do tests after clinical assessment. Avoid unnecessary tests, random antibiotics, or repeated medicines without diagnosis.

  5. Step 5

    Follow up and return early if worse

    If symptoms worsen, new warning signs appear, or treatment is not helping, return for review quickly.

Rural patient practical tips
  • Take a written symptom diary and all previous prescriptions/test reports.
  • Do not hide medicines already taken, even herbal or over-the-counter medicines.
  • Ask which warning signs mean urgent referral to hospital.

This roadmap is for education. A real diagnosis and treatment plan requires history, examination, and clinical judgment.

RX Patient Help

Ask a health question safely

Write your symptom story. A health professional or site editor can review it before any answer is prepared. This box is not for emergency care.

Emergency first: Severe chest pain, breathing trouble, unconsciousness, stroke signs, severe injury, heavy bleeding, or rapidly worsening symptoms need urgent local medical care now.

Frequently Asked Questions

Is this article a replacement for a doctor?

No. It is educational content only. Patients should consult a qualified clinician for diagnosis and treatment.

When should I seek urgent care?

Seek urgent care for severe symptoms, rapidly worsening condition, breathing difficulty, severe pain, neurological changes, or any emergency warning sign.

References

Add references, clinical guidelines, textbooks, journal articles, or trusted medical sources here. You can edit this area from the RX Article Professional Blocks panel.

More from this topic
  1. Congenital Enterocyte Heparan Sulfate Deficiency

    DefinitionCongenital? enterocyte heparan sulfate deficiency is a very rare, severe, genetic intestinal disease. In this condition, the small bowel lining cells, called enterocytes, do not show...

    April 3, 2026 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)
  2. Congenital ectropion uveae

    DefinitionCongenital? ectropion uveae, often shortened to CEU, is a very rare eye condition present from birth. In this condition, the dark pigment layer that normally stays...

    April 2, 2026 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)
  3. Congenital Dyserythropoietic Anemia, Type III

    DefinitionCongenital? dyserythropoietic anemia?, type III, also called CDA type III, is a very rare inherited blood disease. In this disease, the bone marrow tries to make...

    April 2, 2026 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)
  4. Congenital Dyserythropoietic Anemia Type I

    DefinitionCongenital? dyserythropoietic anemia?, type I, usually called CDA type I, is a rare inherited blood disease. In this disease, the bone marrow tries to make red...

    April 1, 2026 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)
  5. Congenital Dyserythropoietic Anemia Due to KLF1 Mutation

    DefinitionCongenital? dyserythropoietic anemia? due to KLF1 mutation is a very rare inherited red blood cell disease. In most reported cases, doctors describe it as congenital? dyserythropoietic...

    April 1, 2026 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)
  6. Congenital Dyserythropoietic Anemia Due to KLF1 Mutation

    DefinitionCongenital? dyserythropoietic anemia? due to KLF1 mutation is a very rare inherited red blood cell disease. In most reported cases, doctors describe it as congenital? dyserythropoietic...

    April 1, 2026 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)
  7. HEMPAS – Hereditary Erythroblast Multinuclearity with Positive Acid Serum Test

    DefinitionHEMPAS – Hereditary Erythroblast Multinuclearity with Positive Acid Serum Test is a rare inherited blood disease. Its full old name is hereditary erythroblastic multinuclearity with positive...

    April 1, 2026 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)
  8. Congenital Dyserythropoietic Anemia Type 2

    DefinitionCongenital? dyserythropoietic anemia? type 2, also called CDA type II, is a rare inherited blood disease. In this disease, the body makes red blood cells in...

    April 1, 2026 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)
  9. Component of Oligomeric Golgi Complex 2–Congenital Disorder of Glycosylation

    DefinitionComponent of oligomeric Golgi complex 2–congenital? disorder of glycosylation is usually called COG2-CDG. It is a very rare inherited metabolic disease. In this disease, both copies...

    April 1, 2026 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)
  10. Congenital Disorder of Glycosylation, Type IIq

    DefinitionCongenital? disorder of glycosylation, type IIq, is a very rare inherited metabolic disease. It is now also commonly called COG2-CDG because it is caused by harmful...

    April 1, 2026 • Rx Autoimmune, Genetic and Rare Diseases (A - Z)