CHSU Discovery

Abstract:
Introduction and Background: Hemophagocytic lymphohistiocytosis (HLH) is a severe, life-threatening inflammatory disorder, with an estimated annual incidence of 1.5 per million, affecting multiple organ systems and carrying a high risk of mortality if untreated. This case report details the evaluation and management of an adult female presenting with atypical symptoms and focuses on the challenging diagnosis of HLH in the setting of overlapping differential diagnoses.

Case Presentation: A 69-year-old female initially presented with fever, respiratory distress, acute kidney injury, altered mental status, and a profound drop in platelet count, prompting an extensive differential diagnosis. Initial laboratory results indicated a microangiopathic process with 1+ schistocytes and a platelet count below 20,000. Elevated D-dimer, low fibrinogen, mild coagulopathies, and infectious symptoms initially suggested disseminated intravascular coagulation (DIC) in the context of sepsis. Thrombotic thrombocytopenic purpura (TTP) was also suspected, and ADAMTS13 testing was conducted on presentation. Despite platelet transfusion attempts, the patient’s acute kidney injury and altered mental status worsened, raising suspicion of TTP. As plasma exchange was planned, worsening liver enzymes led to consideration of HLH. Workup results, including ferritin exceeding 10,000 and markedly elevated triglycerides, supported the suspicion of HLH. A bone marrow biopsy was conducted, and empirical steroids were initiated, resulting in immediate improvements in mental status, liver enzymes, and creatinine. The HLH diagnosis was formally confirmed with evidence of diffuse hemophagocytosis in the bone marrow and positive soluble interleukin-2. Etoposide was subsequently initiated, leading to continued symptom improvement. The patient later tested positive for Q-fever, Rickettsia typhi, and Epstein-barr virus, suggesting these infections likely triggered HLH. Following the initiation of etoposide and steroids, the patient’s condition improved, and she was discharged for outpatient HLH treatment.

Conclusion: The case emphasizes the diagnostic intricacies in differentiating HLH amid overlapping conditions. By highlighting the complexities of patient presentation, diagnosis, and management, this case aims to enhance the recognition and understanding of this critical condition in the adult population and the urgency of timely diagnosis and intervention.