18 An uncommon overlap of two common rheumatological disorders

Abstract

Background Juvenile systemic lupus erythematosus (SLE) is a heterogeneous multisystem autoimmune disease. Kawasaki disease (KD) is a common vasculitic disorder in children that manifests with fever and mucocutaneous involvement. While overlap of childhood SLE with other rheumatologic disorders has been described, it is extremely unusual in the context of KD. We report 2 children who concomitantly had SLE and KD. Methods Patient 1: A 5-year-old boy presented with fever of 2 months. He was irritable, he had malar rash, generalized erythematosus maculopapular rash, oral ulcers, red cracked lips, conjunctival injection, cervical adenopathy and hepatomegaly. Investigations showed anemia, leucopenia, elevated erythrocyte sedimentation rate (ESR) and high C-reactive protein (CRP). He had hypocomplimentemia; positive antinuclear antibody (ANA) (4+diffuse pattern) and high anti-dsDNA antibody titre (1560 IU/mL). Diagnosis of SLE was made. One week later he was brought with typical periungual peeling of skin in fingers and toes (figure 1). Investigations showed anemia (haemoglobin- 83 gm/L), thrombocytosis (510×109/L), persistently elevated ESR (61 mm in 1 st hour) and high CRP (16 mg/L). So diagnosis of concomitant KD was considered. Patient 2: A 8 year-old-girl presented with diffuse non scarring alopecia for 2 years and fever for 3 weeks. On examination, she had pallor; red cracked lips; palmar erythema; diffuse alopecia (figure1); generalized lymphadenopathy; hepatomegaly. Investigations revealed anaemia, lymphocytopenia, elevated ESR and CRP, high serum pro-BNP levels. She had hypocomplimentemia; positive ANA (4+diffuse pattern) and positive anti-dsDNA antibody. A diagnosis of SLE was made. But, on day 5 of hospital stay she developed periungual and perianal peeling (figure 1), and chromonychia. On reviewing history, she also had redness of lips and tongue, conjunctival injection and generalized maculopapular rash 5 days prior to admission. Possibility of concomitant KD was considered. Results Both children fulfilled the classification criteria for diagnosis of SLE and KD as well and time course of events was also very suggestive. Patient 1 was administered intravenous immunoglobulin (IVIG) (2 gm/kg), following which his irritability subsided. Patient 2 was also given IVIG (2 gm/kg). Both patients were discharged on oral prednisolone, hydroxychloroquine and low dose aspirin. Aspirin was stopped after 6 weeks as echocardiography was normal. Both continue to remain well on follow-up. Conclusions While overlap of childhood SLE with other rheumatological disorders has been described, concomitant occurrence of SLE and KD is an extremely rare. Two or more rheumatologic diseases may coexist at the same time and one must always be vigilant. Funding Source(s): No funding source.