Observational Study of a French and Belgian Multicenter Cohort of 23 Patients Diagnosed in Adulthood With Mevalonate Kinase Deficiency.

The aim of this study was to describe the clinical and biological features of Mevalonate kinase deficiency (MKD) in patients diagnosed in adulthood. This is a French and Belgian observational retrospective study from 2000 to 2014. To constitute the cohort, we cross-check the genetic and biochemical databases. The clinical, enzymatic, and genetic data were gathered from medical records. Twenty-three patients were analyzed. The mean age at diagnosis was 40 years, with a mean age at onset of symptoms of 3 years. All symptomatic patients had fever. Febrile attacks were mostly associated with arthralgia (90.9%); lymphadenopathy, abdominal pain, and skin lesions (86.4%); pharyngitis (63.6%); cough (59.1%); diarrhea, and hepatosplenomegaly (50.0%). Seven patients had psychiatric symptoms (31.8%). One patient developed recurrent seizures. Three patients experienced renal involvement (13.6%). Two patients had angiomyolipoma (9.1%). All but one tested patients had elevated serum immunoglobulin (Ig) D level. Twenty-one patients had genetic diagnosis; most of them were compound heterozygote (76.2%). p.Val377Ile was the most prevalent mutation. Structural articular damages and systemic AA amyloidosis were the 2 most serious complications. More than 65% of patients displayed decrease in severity and frequency of attacks with increasing age, but only 35% achieved remission. MKD diagnosed in adulthood shared clinical and genetic features with classical pediatric disease. An elevated IgD concentration is a good marker for MKD in adults. Despite a decrease of severity and frequency of attacks with age, only one-third of patients achieved spontaneous remission.

Reactive hemophagocytic syndrome in adult-onset Still disease: clinical features and long-term outcome: a case-control study of 8 patients.

Reactive hemophagocytic syndrome (RHS) is a rare, life-threatening, and little-known complication of rheumatic diseases. This disorder is characterized by fever, pancytopenia, liver failure, coagulopathy, and neurologic symptoms. RHS may develop in patents who have lymphoma, organ transplantation, serious infection, and rheumatic diseases, most notably systemic lupus erythematosus and adult-onset Still disease (AOSD). Observations of specific cases of RHS in AOSD remain rare, and the significance of this syndrome during the course of AOSD remains unknown. We retrospectively studied 16 episodes of AOSD-associated RHS in 8 patients. To determine whether RHS is associated with a particular phenotype of AOSD, we conducted a case-control study from the cohort of AOSD patients seen during the same period. The estimated frequency of RHS in AOSD patients from our cohort was 15.3% (8/52). The median age at RHS diagnosis was 44.5 years. We collected clinical and laboratory data. RHS was the first manifestation of AOSD in 7 cases. The main symptoms were fever (n = 8), salmon rash (n = 6), arthralgia (n = 7), lymphadenopathy (n = 6), and shock (n = 4). Serum ferritin concentration was consistently elevated (>1000 microg/L in 8 cases), and the level of glycosylated ferritin was low in all cases (<5% in 7 cases, 15% in 1 case). Six patients presented with coagulopathy; hypertriglyceridemia was found in 6 cases. Admission to the intensive care unit was required in 4 cases. Treatment included corticosteroids (n = 8) and intravenous immunoglobulin (n = 6), cyclophosphamide in 2 cases, infliximab in the same 2 cases, and cyclosporine in 1 case. With a follow-up ranging from 2 to 15 years, the patients were in remission with prednisone plus methotrexate (n = 4), prednisone plus infliximab (n = 2), and low-dose prednisone alone (n = 2). We compared the 8 patients included in this study with 44 control patients with AOSD without RHS. Low haptoglobin levels, very high ferritin levels (>10,000 microg/L), and a normal or low neutrophil count seem to be predictive factors of the occurrence of RHS in AOSD.