Reassured that in constitutional variants, there is no increased risk of cancer, and no known history of resistance to cyclophosphamide. this patient also demonstrated an interesting antibody pattern, as he was positive for anti-nxp2 antibodies (indicating high risk for calcino- sis) and anti-scl-100 antibodies, which are associated with a clinical subset of patients with overlap of systemic sclerosis and jdm and associated with extensive extra-muscular features. he had two distinct clinical phenotypes of calcinosis, which is probably explained by the presence of two autoantibodies that increase the risk of calcinosis. key learning points/conclusion: although jdm has bimodal age group for presentation in childhood, only 3% of systemic sclerosis are seen in childhood, which makes this an extremely unusual presenta- tion, given the age, gender and the overlap features (clinical and immunological). we explored whether this rare presentation could be linked to the underlying pax8 gene mutations, but we could not find any association. with the clinical diagnosis of systemic sclerosis, it was important to rule out cardiopulmonary complications. the other consideration was regarding the choice of therapeutic agent – whether the germline pax8 gene variants could increase the risk of malignancies or cause resistance to chemotherapeutic agents like cyclophosphamide, for neither of which we could find any evidence. extensive calcinosis cutis in this patient could be explained by the presence of two risk factors (crest syndrome and jdm with nxp2 antibodies)