P084 Recurrent fever in children: why not a mevalonate kinase deficiency?

Background Mevalonate kinase deficiency (MKD) is a rare autosomal recessive auto inflammatory disease. The clinical spectrum of this disease is a continuum ranging from the moderate form of Hyper-IgD syndrome (HIDS) to lethal forms of mevalonic aciduria (MA). An autoinflammatory disease should be considered in children with recurrent fever of unexplained origin. Case report M, 28 months old boy from a non-consanguineous marriage of Algerian parents, presented since the age of two months’ episodes of unexplained fever resistant to antibiotics and requiring several hospitalizations. Family history found that the mother and a maternal uncle experienced an unexplained recurrent fever. Personal history found episodes of fever lasting in average 6 days, with no obvious cause and recurring every 15–20 days; associated with bilateral cervical adenopathy, mouth ulcers, arthralgia, abdominal pain with vomiting and diarrhea. Clinical examination confirmed the fever with temperature of 38.7°, Chills and irritability, Multiple cervical adenopathy oral aphthae, tongue of geographical aspect, cervical pain and large joint arthralgia, tender abdomen with no organomegaly. Biologic workups found major inflammatory syndrome with hyper leucocytosis at 14X103/mm3 predominantly polynuclear, high CRP level, high ESR at 110 mm. Blood cultures and viral serologies were negative. Immunoelectrophoresis found elevated IgA, IgG and IgM with a normal IgD level. Chest X-ray and abdominal ultrasound were normal. The diagnosis of MKD in its moderate form was supported by elevated urinary mevalonic acid excretion to 5.1 mmol/mol during the febrile episode and subsequently confirmed by a 2nd contributory urine assay during another febrile episode. Conclusion MKD is a rare disease. The clinical spectrum of this condition is variable and could benefit of an effective treatment. Our patient developed a moderate form with a better long-term prognosis.