Fatal Kikuchi-like lymphadenitis associated with connective tissue disease: a report of two cases and review of the literature

Introduction: Kikuchi-Fujimoto disease, is usually a benign self-limiting disease which typically affects young females under the age of 30 years and resolves without treatment within six months. However, when it occurs in the context of connective tissue disease, particularly systemic lupus erythematosus (SLE), it is usually associated with a flare-up of the patient's symptoms, requiring treatment, and can lead to severe, potentially life-threatening sequelae. Case description: Here, we report and compare two cases of unclassifiable connective tissue disease who developed a Kikuchi-like lymphadenitis and sepsis-like clinical syndrome, including disseminated intravascular coagulation, which proved rapidly fatal. Discussion and evaluation: In our review of the literature, we found 55 cases of Kikuchi-Fujimoto disease occurring in the context of definite connective tissue disease, 50 of which were associated with SLE. Of the 55 cases, 22 (40%) had simultaneous onset with, 19 (35%) predated the onset of and 14 (25%) developed after the associated connective tissue disease. Life-threatening autoimmune sequelae were reported in 8 cases, 2 of which were fatal. The aetiology of the association remains unknown. Conclusion: Kikuchi-Fujimoto disease is a histopathological diagnosis, and although the classical form appears to represent a distinct entity, it is unclear whether it is always the same entity, regardless of the context in which it occurs, or whether it represents a histological pattern with a variety of possible causes. In any case, the possibility of auto-immune sequelae in patients with known autoimmune disease should always be considered if these patients present with a sepsis-like clinical syndrome and no infective source is identified.