Background Chikungunya virus (CHIKV) is notoriously arthritogenic and is known to cause a wide spectrum of rheumatological disorders.

Objectives To study the Rheumatological Manifestations of CHIKV Infection.

Methods ^{Record of 1641} consecutive patients who presented to the outpatient department (OPD) with history of chikungunya infection (fever, joint pains±rash) during the period of 1 st July 2016 to 31 st October 2016 were checked and recruited from private hospital, camps and clinic from urban and suburban population from 1 st February to 31 st December 2017. The study cohort was subjected to laboratory tests – serum IgM, IgG and RT-PCR for chikungunya virus. Those patients who tested positive for ≥1 lab tests were included in the study. Of the 1641 patients, 408 patients either refused the lab tests or were lost to follow up. Of the remaining 1233 patients, 882 (71.53%) patients tested positive for ≥1 lab tests and 351 (28.47%) tested negative for all the 3 lab tests. These patients were classified into rheumatological disorders as per validated criteria.

Results We studied 882 consecutive patients of chikungunya infection with some rheumatological manifestations. Mean age of study cohort was 53.64±15.82 years with male:female of 398 (45.12%):484(54.88%). Mean disease duration of post CHIKV infection was 08.45±3.64 months. Serologically, isolated serum IgM CHIKV was positive in 128 (14.51%) patients, IgG CHIKV in 340 (38.54%) patients and RT-PCR CHIKV in 223 (25.28%) patients. Combination of serum IgG and IgM CHIKV both were positive in 62 (7.03%), IgM and RT-PCR CHIKV 49 (5.55%) and IgG and RT-PCR CHIKV in 40 (4.54%) patients. All the 3 serum IgM, IgG and RT-PCR CHIKV were positive in 50 (5.67%) patients.

Of these 882 patients, 143 (16.21%) patients had rheumatological disorder prior to CHIKV infection which flared up after the infection. Of the 143 patients, 69 (48.25%) had osteoarthritis (OA) knee, 29 (20.27%) had mechanical low back ache, 12 (8.39%) cervical spondylitis, 10 (6.99%) had rheumatoid arthritis (RA), 7 (4.89%) each adhesive capsulitis and ankylosing spondylitis (AS), 3 (2.1%) psoriatic arthritis (PsA), 2 (1.4%) each had SLE, dequervian tenosynovitis and granulomatosus with polyangitis.

Remaining 739 patients presented with various rheumatological disorders, most common of which was post chikungunya polyarthralgias in 568 (76.86%) patients. Of the 739 patients, 40 (5.4%) patients developed new onset OA knee, 38 (5.14%) met ACR/^{EULAR 2010} criteria for RA, 28 (3.78%) met modified New York criteria for AS, 29 (3.92%) developed undifferentiated arthritis, 17 (2.3%) patients developed various enthesitis and tenosynovitis, 1 (0.14%) patients fulfilled ^{ACR 1997/SLICC 2012} criteria for SLE, 20 (2.7%) patients fulfilled ^{ACR 2010} criteria for fibromyalgia, 5 (0.67%) patients fulfilled CASPAR criteria for PsA, 3 (0.4%) patients fulfilled 2015 classification criteria for Gout.

Family history of RA was present in 4 (10.52%) patients and AS in 9 (32.1%) patients. Co-morbidities as hypothyroid were present in 132 (17.86%) patients, hypertension in 88 (11.90%) and diabetes mellitus in 168 (22.73%) patients.

Limitation of study – This study was not community based and only those patients who had persistent symptoms were recruited. Those patients whose symptoms of CHIKV infection subsided were not included.

Conclusions CHIKV is a worldwide epidemic which precipitates chronic inflammatory rheumatological diseases.

Acknowledgements Nil

Disclosure of Interest None declared