Badshah et al. Journal of Medical Case Reports (2019) 13:241 https://doi.org/10.1186/s13256-019-2146-0 CASE REPORT Open Access Antisynthetase syndrome presenting as interstitial lung disease: a case report Aliena Badshah*, Iqbal Haider, Shayan Pervez and Mohammad Humayun Abstract Background: Antisynthetase syndrome is a relatively uncommon entity, and can be easily missed if not specifically looked for in adults whose initial presentation is with interstitial lung disease. Its presentation with interstitial lung disease alters its prognosis. Case presentation: This case report describes a 27-year-old Pakistani, Asian man, a medical student, with no previous comorbidities or significant family history who presented with a 3 months’ history of low grade fever and lower respiratory tract infections, associated with exertional dyspnea, arthralgias, and gradual weight loss. During these 3 months, he had received multiple orally administered antibiotics for suspected community-acquired pneumonia. When he presented to us, he was pale and febrile. A chest examination was significant for bi-basal end-inspiratory crackles. Preliminary investigations revealed raised erythrocyte sedimentation rate. High resolution computed tomography of his chest showed fine ground-glass attenuation in posterior basal segments of both lower lobes suggestive of interstitial lung disease. He was started on dexamethasone, to which he responded and showed improvement. However, during the course of events, he developed progressive proximal muscle weakness. Further investigations revealed raised creatinine phosphokinase and lactate dehydrogenase. A thorough autoimmune profile was carried out which showed positive anti-Jo-1 antibodies in high titers. A muscle biopsy was consistent with inflammatory myopathy. Clinical, radiological, serological, and histopathological markers aided in making the definitive diagnosis of antisynthetase syndrome. Antisynthetase syndrome is a variant of polymyositis but with visceral involvement, that is, interstitial lung disease and positive anti-Jo-1 antibodies. Our patient responded very well to glucocorticoids and azathioprine. Conclusion: Antisynthetase syndrome is a rare clinical entity which apart from clinical presentation requires specific serological investigations for diagnosis. Concomitant association of interstitial lung disease gives it a guarded prognosis. Keywords: Arthralgia, Myopathy, Interstitial lung disease, Anti-Jo-1 antibodies, Polymyositis, Antisynthetase syndrome Introduction known as antisynthetase antibodies, or anti-ARS [3]. Pa- Antisynthetase syndrome (ASS) is a rare, chronic auto- tients with this syndrome have a characteristic clinical pic- immune disease of undetermined cause. The syndrome is ture consisting of fever, exanthema on the hands (also considered a sub-group of idiopathic inflammatory myop- referred to as mechanic’s hands), myositis, and/or intersti- athies (IIMs) [1]. IIMs are characterized by different de- tial lung disease (ILD), and/or articular involvement. Ray- grees of skeletal muscle inflammation. They are further naud’s phenomenon is frequently observed. The severity divided into three sub-groups: (1) sporadic inclusion-body and type of pulmonary involvement determines the prog- myositis; (2) polymyositis (PM); and (3) dermatomyositis nosis of the disease [4, 5]. (DM) [2]. ASS is a subset of PM/DM. The hallmark of the Anti-Jo-1 was the first anti-ARS discovered. Many disorder is the presence of autoantibodies against the other anti-ARS antibodies were discovered later but aminoacyl-transfer ribonucleic acid (tRNA) synthetase, also nearly all have been discovered recently, and only a few laboratories have the facilities to test for them. Since * Correspondence: [email protected] anti-Jo-1 antibodies are readily tested for in patients Department of Medicine, Khyber Teaching Hospital, Peshawar, Pakistan © The Author(s). 2019 Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated. Badshah et al. Journal of Medical Case Reports (2019) 13:241 Page 2 of 6 suspected of ASS, most of the data on ASS are related tobacco smoking and alcohol intake, presented with 3 to presence of anti-Jo-1 antibodies [6]. months’ history of frequent bouts of lower respiratory The strongest predictor of ILD in patients with ASS is tract infections associated with exertional dyspnea, ar- the presence of anti-Jo-1 antibodies. Nearly 70% of pa- thralgias, gradual weight loss, low grade fever, easy fatig- tients with ASS with ILD have detectable anti-Jo-1 anti- ability, and anorexia. His family history was also bodies. In patients with ASS with ILD, disease activity is insignificant for any respiratory or other systemic path- strongly related to the titers of anti-Jo-1 antibodies. ology. In the fourth month of his illness, his fever be- Other less common variants of anti-ARS antibodies in- came high grade associated with profuse sweating. All clude: anti-PL-7, anti-PL-12, anti-OJ, anti-EJ, anti-KS, the baseline investigations were carried out on an out- anti-ZO, and anti-tyrosyl antibodies [6]. patient basis. His white cell count was raised and a chest We discuss the case of a patient who initially pre- X-ray showed basal consolidation. A suspicion of pneu- sented with features of ILD, but subsequently developed monia was made and he was started on broad-spectrum musculoskeletal features that could not be explained on antibiotics. His condition improved temporarily but the the basis of ILD alone. Further investigations led to the symptoms re-emerged after a few days. He also received diagnosis of ASS in the patient. We hope that this rare a course of orally administered fluoroquinolones but presentation will add to medical literature and aid in there was no improvement. A subsequent high reso- early diagnosis of other patients presenting with similar lution computed tomography (HRCT) scan of his chest features. revealed bilateral ground-glass haziness with areas of Autoimmune conditions have a high prevalence in the traction bronchiectasis, more so in the posterior basal Western world when compared to Eastern countries. segments of both lower lobes, suggestive of ILD (Figs. 1 ASS, though a well-known and established entity, is and 2). He was given dexamethasone which improved rarely seen in the South Asian part of the world, and so his respiratory symptoms. In the sixth month of illness, the purpose of this case report is to highlight the im- he developed progressive proximal muscle weakness. He portance of keeping in mind this and other autoimmune had difficulty in rising up from a chair and had difficulty conditions in our patients when common conditions in rising up from a squatting position. Throughout this with similar presentations have been excluded. period he had progressive weight loss (19 kg lost in 2 months) and profuse sweating. He was admitted to our Case presentation hospital and thoroughly investigated. With time his A 27-year-old Pakistani, Asian man, a medical student, proximal muscle weakness became severe and defined. It with no previous comorbidities and no past history of now involved his upper limbs as well and he had Fig. 1 CT scan showing features suggestive of Interstitial Lumg Disease (ILD) Badshah et al. Journal of Medical Case Reports (2019) 13:241 Page 3 of 6 Fig. 2 CT scan showing areas of ground glass haze and traction bronchiectasis difficulty in combing his hair. He also gave a history of creatinine phosphokinase (CPK), anti-Jo-1 positivity, painful and cyanosed finger tips in winter. muscle biopsy, and HRCT findings led to a presumptive He had lost muscle bulk (19 kg lost in 2 months) and diagnosis of ASS. He was commenced on pulsed intra- was pale. He was febrile with recorded fever of 39.4 to venous methyl prednisolone 1 gm daily for 3 days 40.0 °C (103–104 °F). There was symmetric arthralgia followed by orally administered prednisolone (1 mg/kg but no arthritis. A chest examination still revealed bi- body weight), and vitamin D3 and calcium supplements basal inspiratory crackles. at our hospital. He responded to the treatment. His CPK Routine and specialized investigations were carried reduced and symptoms improved. He was discharged on out, which are tabulated in Table 1. orally administered glucocorticoids, orally administered A bone marrow biopsy was done to exclude any mye- azathioprine, proton pump inhibitors, and vitamin D3 loproliferative disorder that could have been responsible analogs (to prevent corticosteroid-induced osteoporosis). for the continuously raised total leukocyte count (TLC). Six months later, he is on a maintenance dose of orally It turned out to be normocellular with no evidence of administered steroids and azathioprine and is symptom leukemia or lymphoma. His 25-hydroxy vitamin-D was free. The case is being presented after informed consent deficient with a value of 4.9 ng/ml (normal value, 30– from the patient. 100 ng/ml; severe deficiency, < 20 ng/ml). An ultrasound of his abdomen was suggestive of only cholelithiasis,