Overlap between systemic sclerosis and polyarteritis nodosa: A case report

BACKGROUND: Systemic sclerosis (SSc) is a multiorgan connective tissue disease characterized by vasculopathy, inflammation, autoimmunity, and fibrosis in the skin, lungs and other organs. The occurrence of frank vasculitis is uncommon. CASE PRESENTATION: A 36-year old male patient with limited cutaneous SSc developed multiple necrotic ulcers on both legs and feet and gangrene of several toes, followed by an acute onset of axonal sensorimotor neuropathy affecting both radial and peroneal nerves, severe testicular pain with gangrenous patches over the scrotum. The hepatitis B virus (HBV) core antibody was positive while HB surface antigen and surface antibody, HAV and HCV antibodies were negative. The polymerase chain reaction for HBV and HCV showed no detectable viraemia. Antineutrophil cytoplasmic antibodies, cryoblobulins, anticardiolipin antibodies, lupus anticoagulant, antimitochondrial and anti- liver-kidney microsomal antibodies were negative. Pelvi-abdominal ultrasound and portal vein Doppler study showed a coarse and heterogeneous echo-texture of the liver, splenomegaly, moderate ascites and an enlarged, patent portal vein. Fibroscan revealed grade III liver fibrosis. He had an attack of haematemesis with elevation of the liver enzymes and low serum albumin and prothrombin concentrations. He was diagnosed as a case of polyarteritis nodosa. He was successfully treated by methylprednisolone intravenous pulses, followed by oral prednisone 40 mg/day. Plasmapheresis and six monthly doses of 1000 mg intravenous cyclophosphamide. Prednisone was gradually tapered to 5 mg/day with addition of azathioprine 100 mg/day. CONCLUSION: The association between systemic sclerosis and polyarteritis nodosa is very rare. The co-existence of SSc and vasculitis necessitates modification of the treatment plan.