Lamotrigine-associated haemophagocytic lymphohistiocytosis (HLH) confounded with underlying rheumatoid arthritis

Haemophagocytic lymphohistiocytosis (HLH) is one of the rare haematological syndromes more commonly reported in infants/children than adults. This disease is known for its aggressive dysregulated immune response affecting the host rapidly, causing multiorgan dysfunction and thus carries a high mortality. The disease still remains cryptic in this current decade despite all the developments in the ever-evolving field of haematology. Due to its rare occurrence and being more frequent in infants and the paediatric population, the literature lacks enough data to standardise therapies. Such events in adults and the elderly are invariably related to an underlying insult such as infections, other autoimmune or rheumatological diseases or drugs. We describe an interesting case of a middle-aged Caucasian woman who presented with fever, pancytopenia and hepatitis, who was eventually diagnosed with HLH just in time to receive the life-saving specific treatment as per available guidelines.