RESUMEN
The term hemolytic uremic syndrome (HUS) refers to a heterogenous group of disorders arising from an initial endothelial cell injury with fibrin and platelet thrombi formation in the vasculature, leading to severe organ damage resulting in the well-known triad of microangiopathic hemolytic anemia, thrombocytopenia and kidney disease. The majority of pediatric cases (90 percent) of HUS are caused by Shiga toxin-producing Escherichia coli (STEC-HUS) or Shigella dysenteriae and rarely with Streptococcus pneumoniae (Pneumococcal-HUS). Atypical hemolytic uremic syndrome (aHUS) constitute only 5 percent of all HUS cases and are mediated by dysregulation of complement proteins. Supportive therapy is the cornerstone of management of HUS. Atypical HUS on the other hand is amenable to treatment with eculizumab; the first FDA approved complement blocker. We present a case of HUS caused by Clostridium difficile in a 16-year-old pediatric patient which has rarely been mentioned in the literature and is the first reported case successfully treated with eculizumab with rapid and sustained improvement in hematologic and kidney disease.
Asunto(s)
Clostridioides difficile , Infecciones por Clostridium , Enterocolitis Seudomembranosa , Síndrome Hemolítico-Urémico , Adolescente , Infecciones por Clostridium/diagnóstico , Enterocolitis Seudomembranosa/diagnóstico , Síndrome Hemolítico-Urémico/diagnóstico , HumanosRESUMEN
Dysproteinemia is excessive production of immunoglobulins from clonal proliferation of plasma or B cells. Cryoglobulins are a special group of immunoglobulins that precipitate below 37 degrees C. Type 1 cryoglobulinemia consists mostly of IgM and IgG that infrequently leads to glomerulonephritis. In these situations, an underlying malignancy is even rare with only 21 cases described so far with only four having chronic lymphocytic leukemia (CLL). We present a case of a 68-year-old male admitted with hypertension and kidney dysfunction who upon work up was found to have CLL. Kidney biopsy was performed that showed capillary loops thickening with massive intraluminal cryoglobulin deposition in the glomeruli on periodic acid-Schiff (PAS) stain and "tram tracking" on silver stains. The patient was started on chemotherapy with rituximab, cyclophosphamide, vincristine, and prednisone. After his fourth and final cycle of treatment, the patient's serum creatinine and Glomerular filtration rate improved to 1.2 mg/dL and 85 mL/min from 3 mg/dL and 29 mL/min respectively. One month later, his renal function remained mostly unchanged. The rare association of type 1 cryoglobulinemia with underlying CLL makes it a unique and intriguing case.