An Unusual Case of Hemophagocytic Lymphohistiocytosis Associated with Mycobacterium Chimaera or Large-Cell Neuroendocrine Carcinoma

Hemophagocytic lymphohistiocytosis (HLH) is a rare and very dangerous condition characterized by abnormal activation of the immune system, causing hemophagocytosis, inflammation, and potentially widespread organ damage. The primary (genetic) form, caused by mutations affecting lymphocyte cytotoxicity, is most commonly seen in children. Secondary HLH is commonly associated with infections, malignancies, and rheumatologic disorders. Most current information on diagnosis and treatment is based on pediatric populations. HLH is a disease that should be diagnosed and treated promptly, otherwise it is fatal. Treatment is directed at treating the triggering disorder, along with symptomatic treatment with dexamethasone and etoposide. We present a 56-year-old patient who was admitted with worsening weakness, exertional dyspnea, dry and nonproductive cough, and a 5-pound weight loss associated with loss of appetite. This is among the rare disorders that are not commonly encountered in day-to-day practice. Our differential diagnoses were broad, including infection, such as visceral leishmaniasis, atypical/tuberculous mycobacteria, histoplasmosis, Ehrlichia, Bartonella, Brucella, Adenovirus, disseminated herpes simplex virus (HSV), hematological-like Langerhans cell histiocytosis, or multicentric Castleman disease; drug reaction, such as drug rash with eosinophilia and systemic symptoms (DRESS); and metabolic disorder, including Wolman\u27s disease (infantile lysosomal acid lipase deficiency) or Gaucher\u27s disease. Based on our investigations as described in our case report, it was narrowed down to hemophagocytic lymphohistiocytosis and COVID-19. Two COVID-19 tests were negative. His lab abnormalities and diagnostic testing revealed hemophagocytic lymphohistiocytosis. He was empirically started on antibiotics and dexamethasone, to be continued for 2 weeks then tapered if the patient showed continued improvement. Dexamethasone was tapered over 8 weeks. He improved on just one of the Food and Drug Administration (FDA)-approved medications, proving that treatment should be tailored to the patient. In addition, in this case study, we included the background, etiology, pathogenesis, diagnosis, management, and prognosis of HLH

Multiple Liver Nodules Mimicking Metastatic Disease as Initial Presentation of Multiple Myeloma

Multiple myeloma is a malignant clonal proliferation of plasma cells in the bone marrow preceded by monoclonal gammopathy of undetermined significance. Initial presentation of multiple myeloma as extramedullary spread in soft tissues particularly in the liver is uncommon. We report a case of a 74-year-old African American female who presented with epigastric pain, hematemesis, elevated alkaline phosphatase, and gamma-glutamyl transferase. Initial impression was peptic ulcer disease; however, ultrasound and CT scan of the abdomen showed multiple liver nodules and perihepatic lymphadenopathy suggestive of metastatic disease. Biopsy of the liver nodules showed CD138 and kappa light chain-restricted positive cells consistent with extramedullary spread of multiple myeloma to the liver. The patient achieved partial response after 6 months of treatment with Velcade, cyclophosphamide, and dexamethasone (VCD). Due to severe neutropenia from cyclophosphamide, regimen was switched to Velcade, Revlimid, and dexamethasone (VRD) which resulted to very good partial response in 1 year which eventually persisted after 4 years. No controlled prospective studies have defined the standard treatment for multiple myeloma with extramedullary spread particularly to the liver. Treatment of multiple myeloma with extramedullary disease follows guidelines for multiple myeloma